xref: /openbsd-src/gnu/llvm/lldb/tools/debugserver/source/RNBRemote.cpp (revision 5a38ef86d0b61900239c7913d24a05e7b88a58f0)
1 //===-- RNBRemote.cpp -------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  Created by Greg Clayton on 12/12/07.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "RNBRemote.h"
14 
15 #include <bsm/audit.h>
16 #include <bsm/audit_session.h>
17 #include <cerrno>
18 #include <csignal>
19 #include <libproc.h>
20 #include <mach-o/loader.h>
21 #include <mach/exception_types.h>
22 #include <mach/mach_vm.h>
23 #include <mach/task_info.h>
24 #include <pwd.h>
25 #include <sys/stat.h>
26 #include <sys/sysctl.h>
27 #include <unistd.h>
28 
29 #if defined(__APPLE__)
30 #include <pthread.h>
31 #include <sched.h>
32 #endif
33 
34 #include "DNB.h"
35 #include "DNBDataRef.h"
36 #include "DNBLog.h"
37 #include "DNBThreadResumeActions.h"
38 #include "JSON.h"
39 #include "JSONGenerator.h"
40 #include "JSONGenerator.h"
41 #include "MacOSX/Genealogy.h"
42 #include "OsLogger.h"
43 #include "RNBContext.h"
44 #include "RNBServices.h"
45 #include "RNBSocket.h"
46 #include "StdStringExtractor.h"
47 
48 #include <compression.h>
49 
50 #include <TargetConditionals.h>
51 #include <iomanip>
52 #include <memory>
53 #include <sstream>
54 #include <unordered_set>
55 
56 #include <CoreFoundation/CoreFoundation.h>
57 #include <Security/Security.h>
58 
59 // constants
60 
61 static const std::string OS_LOG_EVENTS_KEY_NAME("events");
62 static const std::string JSON_ASYNC_TYPE_KEY_NAME("type");
63 
64 // std::iostream formatting macros
65 #define RAW_HEXBASE std::setfill('0') << std::hex << std::right
66 #define HEXBASE '0' << 'x' << RAW_HEXBASE
67 #define RAWHEX8(x) RAW_HEXBASE << std::setw(2) << ((uint32_t)((uint8_t)x))
68 #define RAWHEX16 RAW_HEXBASE << std::setw(4)
69 #define RAWHEX32 RAW_HEXBASE << std::setw(8)
70 #define RAWHEX64 RAW_HEXBASE << std::setw(16)
71 #define HEX8(x) HEXBASE << std::setw(2) << ((uint32_t)(x))
72 #define HEX16 HEXBASE << std::setw(4)
73 #define HEX32 HEXBASE << std::setw(8)
74 #define HEX64 HEXBASE << std::setw(16)
75 #define RAW_HEX(x) RAW_HEXBASE << std::setw(sizeof(x) * 2) << (x)
76 #define HEX(x) HEXBASE << std::setw(sizeof(x) * 2) << (x)
77 #define RAWHEX_SIZE(x, sz) RAW_HEXBASE << std::setw((sz)) << (x)
78 #define HEX_SIZE(x, sz) HEXBASE << std::setw((sz)) << (x)
79 #define STRING_WIDTH(w) std::setfill(' ') << std::setw(w)
80 #define LEFT_STRING_WIDTH(s, w)                                                \
81   std::left << std::setfill(' ') << std::setw(w) << (s) << std::right
82 #define DECIMAL std::dec << std::setfill(' ')
83 #define DECIMAL_WIDTH(w) DECIMAL << std::setw(w)
84 #define FLOAT(n, d)                                                            \
85   std::setfill(' ') << std::setw((n) + (d) + 1) << std::setprecision(d)        \
86                     << std::showpoint << std::fixed
87 #define INDENT_WITH_SPACES(iword_idx)                                          \
88   std::setfill(' ') << std::setw((iword_idx)) << ""
89 #define INDENT_WITH_TABS(iword_idx)                                            \
90   std::setfill('\t') << std::setw((iword_idx)) << ""
91 // Class to handle communications via gdb remote protocol.
92 
93 // Prototypes
94 
95 static std::string binary_encode_string(const std::string &s);
96 
97 // Decode a single hex character and return the hex value as a number or
98 // -1 if "ch" is not a hex character.
99 static inline int xdigit_to_sint(char ch) {
100   if (ch >= 'a' && ch <= 'f')
101     return 10 + ch - 'a';
102   if (ch >= 'A' && ch <= 'F')
103     return 10 + ch - 'A';
104   if (ch >= '0' && ch <= '9')
105     return ch - '0';
106   return -1;
107 }
108 
109 // Decode a single hex ASCII byte. Return -1 on failure, a value 0-255
110 // on success.
111 static inline int decoded_hex_ascii_char(const char *p) {
112   const int hi_nibble = xdigit_to_sint(p[0]);
113   if (hi_nibble == -1)
114     return -1;
115   const int lo_nibble = xdigit_to_sint(p[1]);
116   if (lo_nibble == -1)
117     return -1;
118   return (uint8_t)((hi_nibble << 4) + lo_nibble);
119 }
120 
121 // Decode a hex ASCII string back into a string
122 static std::string decode_hex_ascii_string(const char *p,
123                                            uint32_t max_length = UINT32_MAX) {
124   std::string arg;
125   if (p) {
126     for (const char *c = p; ((c - p) / 2) < max_length; c += 2) {
127       int ch = decoded_hex_ascii_char(c);
128       if (ch == -1)
129         break;
130       else
131         arg.push_back(ch);
132     }
133   }
134   return arg;
135 }
136 
137 uint64_t decode_uint64(const char *p, int base, char **end = nullptr,
138                        uint64_t fail_value = 0) {
139   nub_addr_t addr = strtoull(p, end, 16);
140   if (addr == 0 && errno != 0)
141     return fail_value;
142   return addr;
143 }
144 
145 extern void ASLLogCallback(void *baton, uint32_t flags, const char *format,
146                            va_list args);
147 
148 // from System.framework/Versions/B/PrivateHeaders/sys/codesign.h
149 extern "C" {
150 #define CS_OPS_STATUS 0       /* return status */
151 #define CS_RESTRICT 0x0000800 /* tell dyld to treat restricted */
152 int csops(pid_t pid, unsigned int ops, void *useraddr, size_t usersize);
153 
154 // from rootless.h
155 bool rootless_allows_task_for_pid(pid_t pid);
156 
157 // from sys/csr.h
158 typedef uint32_t csr_config_t;
159 #define CSR_ALLOW_TASK_FOR_PID (1 << 2)
160 int csr_check(csr_config_t mask);
161 }
162 
163 RNBRemote::RNBRemote()
164     : m_ctx(), m_comm(), m_arch(), m_continue_thread(-1), m_thread(-1),
165       m_mutex(), m_dispatch_queue_offsets(),
166       m_dispatch_queue_offsets_addr(INVALID_NUB_ADDRESS),
167       m_qSymbol_index(UINT32_MAX), m_packets_recvd(0), m_packets(),
168       m_rx_packets(), m_rx_partial_data(), m_rx_pthread(0),
169       m_max_payload_size(DEFAULT_GDB_REMOTE_PROTOCOL_BUFSIZE - 4),
170       m_extended_mode(false), m_noack_mode(false),
171       m_thread_suffix_supported(false), m_list_threads_in_stop_reply(false),
172       m_compression_minsize(384), m_enable_compression_next_send_packet(false),
173       m_compression_mode(compression_types::none) {
174   DNBLogThreadedIf(LOG_RNB_REMOTE, "%s", __PRETTY_FUNCTION__);
175   CreatePacketTable();
176 }
177 
178 RNBRemote::~RNBRemote() {
179   DNBLogThreadedIf(LOG_RNB_REMOTE, "%s", __PRETTY_FUNCTION__);
180   StopReadRemoteDataThread();
181 }
182 
183 void RNBRemote::CreatePacketTable() {
184   // Step required to add new packets:
185   // 1 - Add new enumeration to RNBRemote::PacketEnum
186   // 2 - Create the RNBRemote::HandlePacket_ function if a new function is
187   // needed
188   // 3 - Register the Packet definition with any needed callbacks in this
189   // function
190   //          - If no response is needed for a command, then use NULL for the
191   //          normal callback
192   //          - If the packet is not supported while the target is running, use
193   //          NULL for the async callback
194   // 4 - If the packet is a standard packet (starts with a '$' character
195   //      followed by the payload and then '#' and checksum, then you are done
196   //      else go on to step 5
197   // 5 - if the packet is a fixed length packet:
198   //      - modify the switch statement for the first character in the payload
199   //        in RNBRemote::CommDataReceived so it doesn't reject the new packet
200   //        type as invalid
201   //      - modify the switch statement for the first character in the payload
202   //        in RNBRemote::GetPacketPayload and make sure the payload of the
203   //        packet
204   //        is returned correctly
205 
206   std::vector<Packet> &t = m_packets;
207   t.push_back(Packet(ack, NULL, NULL, "+", "ACK"));
208   t.push_back(Packet(nack, NULL, NULL, "-", "!ACK"));
209   t.push_back(Packet(read_memory, &RNBRemote::HandlePacket_m, NULL, "m",
210                      "Read memory"));
211   t.push_back(Packet(read_register, &RNBRemote::HandlePacket_p, NULL, "p",
212                      "Read one register"));
213   t.push_back(Packet(read_general_regs, &RNBRemote::HandlePacket_g, NULL, "g",
214                      "Read registers"));
215   t.push_back(Packet(write_memory, &RNBRemote::HandlePacket_M, NULL, "M",
216                      "Write memory"));
217   t.push_back(Packet(write_register, &RNBRemote::HandlePacket_P, NULL, "P",
218                      "Write one register"));
219   t.push_back(Packet(write_general_regs, &RNBRemote::HandlePacket_G, NULL, "G",
220                      "Write registers"));
221   t.push_back(Packet(insert_mem_bp, &RNBRemote::HandlePacket_z, NULL, "Z0",
222                      "Insert memory breakpoint"));
223   t.push_back(Packet(remove_mem_bp, &RNBRemote::HandlePacket_z, NULL, "z0",
224                      "Remove memory breakpoint"));
225   t.push_back(Packet(single_step, &RNBRemote::HandlePacket_s, NULL, "s",
226                      "Single step"));
227   t.push_back(Packet(cont, &RNBRemote::HandlePacket_c, NULL, "c", "continue"));
228   t.push_back(Packet(single_step_with_sig, &RNBRemote::HandlePacket_S, NULL,
229                      "S", "Single step with signal"));
230   t.push_back(
231       Packet(set_thread, &RNBRemote::HandlePacket_H, NULL, "H", "Set thread"));
232   t.push_back(Packet(halt, &RNBRemote::HandlePacket_last_signal,
233                      &RNBRemote::HandlePacket_stop_process, "\x03", "^C"));
234   //  t.push_back (Packet (use_extended_mode,
235   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "!", "Use extended mode"));
236   t.push_back(Packet(why_halted, &RNBRemote::HandlePacket_last_signal, NULL,
237                      "?", "Why did target halt"));
238   t.push_back(
239       Packet(set_argv, &RNBRemote::HandlePacket_A, NULL, "A", "Set argv"));
240   //  t.push_back (Packet (set_bp,
241   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "B", "Set/clear
242   //  breakpoint"));
243   t.push_back(Packet(continue_with_sig, &RNBRemote::HandlePacket_C, NULL, "C",
244                      "Continue with signal"));
245   t.push_back(Packet(detach, &RNBRemote::HandlePacket_D, NULL, "D",
246                      "Detach gdb from remote system"));
247   //  t.push_back (Packet (step_inferior_one_cycle,
248   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "i", "Step inferior by one
249   //  clock cycle"));
250   //  t.push_back (Packet (signal_and_step_inf_one_cycle,
251   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "I", "Signal inferior, then
252   //  step one clock cycle"));
253   t.push_back(Packet(kill, &RNBRemote::HandlePacket_k, NULL, "k", "Kill"));
254   //  t.push_back (Packet (restart,
255   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "R", "Restart inferior"));
256   //  t.push_back (Packet (search_mem_backwards,
257   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "t", "Search memory
258   //  backwards"));
259   t.push_back(Packet(thread_alive_p, &RNBRemote::HandlePacket_T, NULL, "T",
260                      "Is thread alive"));
261   t.push_back(Packet(query_supported_features,
262                      &RNBRemote::HandlePacket_qSupported, NULL, "qSupported",
263                      "Query about supported features"));
264   t.push_back(Packet(vattach, &RNBRemote::HandlePacket_v, NULL, "vAttach",
265                      "Attach to a new process"));
266   t.push_back(Packet(vattachwait, &RNBRemote::HandlePacket_v, NULL,
267                      "vAttachWait",
268                      "Wait for a process to start up then attach to it"));
269   t.push_back(Packet(vattachorwait, &RNBRemote::HandlePacket_v, NULL,
270                      "vAttachOrWait", "Attach to the process or if it doesn't "
271                                       "exist, wait for the process to start up "
272                                       "then attach to it"));
273   t.push_back(Packet(vattachname, &RNBRemote::HandlePacket_v, NULL,
274                      "vAttachName", "Attach to an existing process by name"));
275   t.push_back(Packet(vcont_list_actions, &RNBRemote::HandlePacket_v, NULL,
276                      "vCont;", "Verbose resume with thread actions"));
277   t.push_back(Packet(vcont_list_actions, &RNBRemote::HandlePacket_v, NULL,
278                      "vCont?",
279                      "List valid continue-with-thread-actions actions"));
280   t.push_back(Packet(read_data_from_memory, &RNBRemote::HandlePacket_x, NULL,
281                      "x", "Read data from memory"));
282   t.push_back(Packet(write_data_to_memory, &RNBRemote::HandlePacket_X, NULL,
283                      "X", "Write data to memory"));
284   t.push_back(Packet(insert_hardware_bp, &RNBRemote::HandlePacket_z, NULL, "Z1",
285                      "Insert hardware breakpoint"));
286   t.push_back(Packet(remove_hardware_bp, &RNBRemote::HandlePacket_z, NULL, "z1",
287                      "Remove hardware breakpoint"));
288   t.push_back(Packet(insert_write_watch_bp, &RNBRemote::HandlePacket_z, NULL,
289                      "Z2", "Insert write watchpoint"));
290   t.push_back(Packet(remove_write_watch_bp, &RNBRemote::HandlePacket_z, NULL,
291                      "z2", "Remove write watchpoint"));
292   t.push_back(Packet(insert_read_watch_bp, &RNBRemote::HandlePacket_z, NULL,
293                      "Z3", "Insert read watchpoint"));
294   t.push_back(Packet(remove_read_watch_bp, &RNBRemote::HandlePacket_z, NULL,
295                      "z3", "Remove read watchpoint"));
296   t.push_back(Packet(insert_access_watch_bp, &RNBRemote::HandlePacket_z, NULL,
297                      "Z4", "Insert access watchpoint"));
298   t.push_back(Packet(remove_access_watch_bp, &RNBRemote::HandlePacket_z, NULL,
299                      "z4", "Remove access watchpoint"));
300   t.push_back(Packet(query_monitor, &RNBRemote::HandlePacket_qRcmd, NULL,
301                      "qRcmd", "Monitor command"));
302   t.push_back(Packet(query_current_thread_id, &RNBRemote::HandlePacket_qC, NULL,
303                      "qC", "Query current thread ID"));
304   t.push_back(Packet(query_echo, &RNBRemote::HandlePacket_qEcho, NULL, "qEcho:",
305                      "Echo the packet back to allow the debugger to sync up "
306                      "with this server"));
307   t.push_back(Packet(query_get_pid, &RNBRemote::HandlePacket_qGetPid, NULL,
308                      "qGetPid", "Query process id"));
309   t.push_back(Packet(query_thread_ids_first,
310                      &RNBRemote::HandlePacket_qThreadInfo, NULL, "qfThreadInfo",
311                      "Get list of active threads (first req)"));
312   t.push_back(Packet(query_thread_ids_subsequent,
313                      &RNBRemote::HandlePacket_qThreadInfo, NULL, "qsThreadInfo",
314                      "Get list of active threads (subsequent req)"));
315   // APPLE LOCAL: qThreadStopInfo
316   // syntax: qThreadStopInfoTTTT
317   //  TTTT is hex thread ID
318   t.push_back(Packet(query_thread_stop_info,
319                      &RNBRemote::HandlePacket_qThreadStopInfo, NULL,
320                      "qThreadStopInfo",
321                      "Get detailed info on why the specified thread stopped"));
322   t.push_back(Packet(query_thread_extra_info,
323                      &RNBRemote::HandlePacket_qThreadExtraInfo, NULL,
324                      "qThreadExtraInfo", "Get printable status of a thread"));
325   //  t.push_back (Packet (query_image_offsets,
326   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "qOffsets", "Report offset
327   //  of loaded program"));
328   t.push_back(Packet(
329       query_launch_success, &RNBRemote::HandlePacket_qLaunchSuccess, NULL,
330       "qLaunchSuccess", "Report the success or failure of the launch attempt"));
331   t.push_back(
332       Packet(query_register_info, &RNBRemote::HandlePacket_qRegisterInfo, NULL,
333              "qRegisterInfo",
334              "Dynamically discover remote register context information."));
335   t.push_back(Packet(
336       query_shlib_notify_info_addr, &RNBRemote::HandlePacket_qShlibInfoAddr,
337       NULL, "qShlibInfoAddr", "Returns the address that contains info needed "
338                               "for getting shared library notifications"));
339   t.push_back(Packet(query_step_packet_supported,
340                      &RNBRemote::HandlePacket_qStepPacketSupported, NULL,
341                      "qStepPacketSupported",
342                      "Replys with OK if the 's' packet is supported."));
343   t.push_back(
344       Packet(query_vattachorwait_supported,
345              &RNBRemote::HandlePacket_qVAttachOrWaitSupported, NULL,
346              "qVAttachOrWaitSupported",
347              "Replys with OK if the 'vAttachOrWait' packet is supported."));
348   t.push_back(
349       Packet(query_sync_thread_state_supported,
350              &RNBRemote::HandlePacket_qSyncThreadStateSupported, NULL,
351              "qSyncThreadStateSupported",
352              "Replys with OK if the 'QSyncThreadState:' packet is supported."));
353   t.push_back(Packet(
354       query_host_info, &RNBRemote::HandlePacket_qHostInfo, NULL, "qHostInfo",
355       "Replies with multiple 'key:value;' tuples appended to each other."));
356   t.push_back(Packet(
357       query_gdb_server_version, &RNBRemote::HandlePacket_qGDBServerVersion,
358       NULL, "qGDBServerVersion",
359       "Replies with multiple 'key:value;' tuples appended to each other."));
360   t.push_back(Packet(
361       query_process_info, &RNBRemote::HandlePacket_qProcessInfo, NULL,
362       "qProcessInfo",
363       "Replies with multiple 'key:value;' tuples appended to each other."));
364   t.push_back(Packet(
365       query_symbol_lookup, &RNBRemote::HandlePacket_qSymbol, NULL, "qSymbol:",
366       "Notify that host debugger is ready to do symbol lookups"));
367   t.push_back(Packet(json_query_thread_extended_info,
368                      &RNBRemote::HandlePacket_jThreadExtendedInfo, NULL,
369                      "jThreadExtendedInfo",
370                      "Replies with JSON data of thread extended information."));
371   t.push_back(Packet(json_query_get_loaded_dynamic_libraries_infos,
372                      &RNBRemote::HandlePacket_jGetLoadedDynamicLibrariesInfos,
373                      NULL, "jGetLoadedDynamicLibrariesInfos",
374                      "Replies with JSON data of all the shared libraries "
375                      "loaded in this process."));
376   t.push_back(
377       Packet(json_query_threads_info, &RNBRemote::HandlePacket_jThreadsInfo,
378              NULL, "jThreadsInfo",
379              "Replies with JSON data with information about all threads."));
380   t.push_back(Packet(json_query_get_shared_cache_info,
381                      &RNBRemote::HandlePacket_jGetSharedCacheInfo, NULL,
382                      "jGetSharedCacheInfo", "Replies with JSON data about the "
383                                             "location and uuid of the shared "
384                                             "cache in the inferior process."));
385   t.push_back(Packet(start_noack_mode, &RNBRemote::HandlePacket_QStartNoAckMode,
386                      NULL, "QStartNoAckMode",
387                      "Request that " DEBUGSERVER_PROGRAM_NAME
388                      " stop acking remote protocol packets"));
389   t.push_back(Packet(prefix_reg_packets_with_tid,
390                      &RNBRemote::HandlePacket_QThreadSuffixSupported, NULL,
391                      "QThreadSuffixSupported",
392                      "Check if thread specific packets (register packets 'g', "
393                      "'G', 'p', and 'P') support having the thread ID appended "
394                      "to the end of the command"));
395   t.push_back(Packet(set_logging_mode, &RNBRemote::HandlePacket_QSetLogging,
396                      NULL, "QSetLogging:", "Check if register packets ('g', "
397                                            "'G', 'p', and 'P' support having "
398                                            "the thread ID prefix"));
399   t.push_back(Packet(
400       set_max_packet_size, &RNBRemote::HandlePacket_QSetMaxPacketSize, NULL,
401       "QSetMaxPacketSize:",
402       "Tell " DEBUGSERVER_PROGRAM_NAME " the max sized packet gdb can handle"));
403   t.push_back(Packet(
404       set_max_payload_size, &RNBRemote::HandlePacket_QSetMaxPayloadSize, NULL,
405       "QSetMaxPayloadSize:", "Tell " DEBUGSERVER_PROGRAM_NAME
406                              " the max sized payload gdb can handle"));
407   t.push_back(
408       Packet(set_environment_variable, &RNBRemote::HandlePacket_QEnvironment,
409              NULL, "QEnvironment:",
410              "Add an environment variable to the inferior's environment"));
411   t.push_back(
412       Packet(set_environment_variable_hex,
413              &RNBRemote::HandlePacket_QEnvironmentHexEncoded, NULL,
414              "QEnvironmentHexEncoded:",
415              "Add an environment variable to the inferior's environment"));
416   t.push_back(Packet(set_launch_arch, &RNBRemote::HandlePacket_QLaunchArch,
417                      NULL, "QLaunchArch:", "Set the architecture to use when "
418                                            "launching a process for hosts that "
419                                            "can run multiple architecture "
420                                            "slices from universal files."));
421   t.push_back(Packet(set_disable_aslr, &RNBRemote::HandlePacket_QSetDisableASLR,
422                      NULL, "QSetDisableASLR:",
423                      "Set whether to disable ASLR when launching the process "
424                      "with the set argv ('A') packet"));
425   t.push_back(Packet(set_stdin, &RNBRemote::HandlePacket_QSetSTDIO, NULL,
426                      "QSetSTDIN:", "Set the standard input for a process to be "
427                                    "launched with the 'A' packet"));
428   t.push_back(Packet(set_stdout, &RNBRemote::HandlePacket_QSetSTDIO, NULL,
429                      "QSetSTDOUT:", "Set the standard output for a process to "
430                                     "be launched with the 'A' packet"));
431   t.push_back(Packet(set_stderr, &RNBRemote::HandlePacket_QSetSTDIO, NULL,
432                      "QSetSTDERR:", "Set the standard error for a process to "
433                                     "be launched with the 'A' packet"));
434   t.push_back(Packet(set_working_dir, &RNBRemote::HandlePacket_QSetWorkingDir,
435                      NULL, "QSetWorkingDir:", "Set the working directory for a "
436                                               "process to be launched with the "
437                                               "'A' packet"));
438   t.push_back(Packet(set_list_threads_in_stop_reply,
439                      &RNBRemote::HandlePacket_QListThreadsInStopReply, NULL,
440                      "QListThreadsInStopReply",
441                      "Set if the 'threads' key should be added to the stop "
442                      "reply packets with a list of all thread IDs."));
443   t.push_back(Packet(
444       sync_thread_state, &RNBRemote::HandlePacket_QSyncThreadState, NULL,
445       "QSyncThreadState:", "Do whatever is necessary to make sure 'thread' is "
446                            "in a safe state to call functions on."));
447   //  t.push_back (Packet (pass_signals_to_inferior,
448   //  &RNBRemote::HandlePacket_UNIMPLEMENTED, NULL, "QPassSignals:", "Specify
449   //  which signals are passed to the inferior"));
450   t.push_back(Packet(allocate_memory, &RNBRemote::HandlePacket_AllocateMemory,
451                      NULL, "_M", "Allocate memory in the inferior process."));
452   t.push_back(Packet(deallocate_memory,
453                      &RNBRemote::HandlePacket_DeallocateMemory, NULL, "_m",
454                      "Deallocate memory in the inferior process."));
455   t.push_back(Packet(
456       save_register_state, &RNBRemote::HandlePacket_SaveRegisterState, NULL,
457       "QSaveRegisterState", "Save the register state for the current thread "
458                             "and return a decimal save ID."));
459   t.push_back(Packet(restore_register_state,
460                      &RNBRemote::HandlePacket_RestoreRegisterState, NULL,
461                      "QRestoreRegisterState:",
462                      "Restore the register state given a save ID previously "
463                      "returned from a call to QSaveRegisterState."));
464   t.push_back(Packet(
465       memory_region_info, &RNBRemote::HandlePacket_MemoryRegionInfo, NULL,
466       "qMemoryRegionInfo", "Return size and attributes of a memory region that "
467                            "contains the given address"));
468   t.push_back(Packet(get_profile_data, &RNBRemote::HandlePacket_GetProfileData,
469                      NULL, "qGetProfileData",
470                      "Return profiling data of the current target."));
471   t.push_back(Packet(set_enable_profiling,
472                      &RNBRemote::HandlePacket_SetEnableAsyncProfiling, NULL,
473                      "QSetEnableAsyncProfiling",
474                      "Enable or disable the profiling of current target."));
475   t.push_back(Packet(enable_compression,
476                      &RNBRemote::HandlePacket_QEnableCompression, NULL,
477                      "QEnableCompression:",
478                      "Enable compression for the remainder of the connection"));
479   t.push_back(Packet(watchpoint_support_info,
480                      &RNBRemote::HandlePacket_WatchpointSupportInfo, NULL,
481                      "qWatchpointSupportInfo",
482                      "Return the number of supported hardware watchpoints"));
483   t.push_back(Packet(set_process_event,
484                      &RNBRemote::HandlePacket_QSetProcessEvent, NULL,
485                      "QSetProcessEvent:", "Set a process event, to be passed "
486                                           "to the process, can be set before "
487                                           "the process is started, or after."));
488   t.push_back(
489       Packet(set_detach_on_error, &RNBRemote::HandlePacket_QSetDetachOnError,
490              NULL, "QSetDetachOnError:",
491              "Set whether debugserver will detach (1) or kill (0) from the "
492              "process it is controlling if it loses connection to lldb."));
493   t.push_back(Packet(
494       speed_test, &RNBRemote::HandlePacket_qSpeedTest, NULL, "qSpeedTest:",
495       "Test the maximum speed at which packet can be sent/received."));
496   t.push_back(Packet(query_transfer, &RNBRemote::HandlePacket_qXfer, NULL,
497                      "qXfer:", "Support the qXfer packet."));
498 }
499 
500 void RNBRemote::FlushSTDIO() {
501   if (m_ctx.HasValidProcessID()) {
502     nub_process_t pid = m_ctx.ProcessID();
503     char buf[256];
504     nub_size_t count;
505     do {
506       count = DNBProcessGetAvailableSTDOUT(pid, buf, sizeof(buf));
507       if (count > 0) {
508         SendSTDOUTPacket(buf, count);
509       }
510     } while (count > 0);
511 
512     do {
513       count = DNBProcessGetAvailableSTDERR(pid, buf, sizeof(buf));
514       if (count > 0) {
515         SendSTDERRPacket(buf, count);
516       }
517     } while (count > 0);
518   }
519 }
520 
521 void RNBRemote::SendAsyncProfileData() {
522   if (m_ctx.HasValidProcessID()) {
523     nub_process_t pid = m_ctx.ProcessID();
524     char buf[1024];
525     nub_size_t count;
526     do {
527       count = DNBProcessGetAvailableProfileData(pid, buf, sizeof(buf));
528       if (count > 0) {
529         SendAsyncProfileDataPacket(buf, count);
530       }
531     } while (count > 0);
532   }
533 }
534 
535 rnb_err_t RNBRemote::SendHexEncodedBytePacket(const char *header,
536                                               const void *buf, size_t buf_len,
537                                               const char *footer) {
538   std::ostringstream packet_sstrm;
539   // Append the header cstr if there was one
540   if (header && header[0])
541     packet_sstrm << header;
542   nub_size_t i;
543   const uint8_t *ubuf8 = (const uint8_t *)buf;
544   for (i = 0; i < buf_len; i++) {
545     packet_sstrm << RAWHEX8(ubuf8[i]);
546   }
547   // Append the footer cstr if there was one
548   if (footer && footer[0])
549     packet_sstrm << footer;
550 
551   return SendPacket(packet_sstrm.str());
552 }
553 
554 rnb_err_t RNBRemote::SendSTDOUTPacket(char *buf, nub_size_t buf_size) {
555   if (buf_size == 0)
556     return rnb_success;
557   return SendHexEncodedBytePacket("O", buf, buf_size, NULL);
558 }
559 
560 rnb_err_t RNBRemote::SendSTDERRPacket(char *buf, nub_size_t buf_size) {
561   if (buf_size == 0)
562     return rnb_success;
563   return SendHexEncodedBytePacket("O", buf, buf_size, NULL);
564 }
565 
566 // This makes use of asynchronous bit 'A' in the gdb remote protocol.
567 rnb_err_t RNBRemote::SendAsyncProfileDataPacket(char *buf,
568                                                 nub_size_t buf_size) {
569   if (buf_size == 0)
570     return rnb_success;
571 
572   std::string packet("A");
573   packet.append(buf, buf_size);
574   return SendPacket(packet);
575 }
576 
577 rnb_err_t
578 RNBRemote::SendAsyncJSONPacket(const JSONGenerator::Dictionary &dictionary) {
579   std::ostringstream stream;
580   // We're choosing something that is easy to spot if we somehow get one
581   // of these coming out at the wrong time (i.e. when the remote side
582   // is not waiting for a process control completion response).
583   stream << "JSON-async:";
584   dictionary.Dump(stream);
585   const std::string payload = binary_encode_string(stream.str());
586   return SendPacket(payload);
587 }
588 
589 // Given a std::string packet contents to send, possibly encode/compress it.
590 // If compression is enabled, the returned std::string will be in one of two
591 // forms:
592 //
593 //    N<original packet contents uncompressed>
594 //    C<size of original decompressed packet>:<packet compressed with the
595 //    requested compression scheme>
596 //
597 // If compression is not requested, the original packet contents are returned
598 
599 std::string RNBRemote::CompressString(const std::string &orig) {
600   std::string compressed;
601   compression_types compression_type = GetCompressionType();
602   if (compression_type != compression_types::none) {
603     bool compress_this_packet = false;
604 
605     if (orig.size() > m_compression_minsize) {
606       compress_this_packet = true;
607     }
608 
609     if (compress_this_packet) {
610       const size_t encoded_data_buf_size = orig.size() + 128;
611       std::vector<uint8_t> encoded_data(encoded_data_buf_size);
612       size_t compressed_size = 0;
613 
614       // Allocate a scratch buffer for libcompression the first
615       // time we see a different compression type; reuse it in
616       // all compression_encode_buffer calls so it doesn't need
617       // to allocate / free its own scratch buffer each time.
618       // This buffer will only be freed when compression type
619       // changes; otherwise it will persist until debugserver
620       // exit.
621 
622       static compression_types g_libcompress_scratchbuf_type = compression_types::none;
623       static void *g_libcompress_scratchbuf = nullptr;
624 
625       if (g_libcompress_scratchbuf_type != compression_type) {
626         if (g_libcompress_scratchbuf) {
627           free (g_libcompress_scratchbuf);
628           g_libcompress_scratchbuf = nullptr;
629         }
630         size_t scratchbuf_size = 0;
631         switch (compression_type) {
632           case compression_types::lz4:
633             scratchbuf_size = compression_encode_scratch_buffer_size (COMPRESSION_LZ4_RAW);
634             break;
635           case compression_types::zlib_deflate:
636             scratchbuf_size = compression_encode_scratch_buffer_size (COMPRESSION_ZLIB);
637             break;
638           case compression_types::lzma:
639             scratchbuf_size = compression_encode_scratch_buffer_size (COMPRESSION_LZMA);
640             break;
641           case compression_types::lzfse:
642             scratchbuf_size = compression_encode_scratch_buffer_size (COMPRESSION_LZFSE);
643             break;
644           default:
645             break;
646         }
647         if (scratchbuf_size > 0) {
648           g_libcompress_scratchbuf = (void*) malloc (scratchbuf_size);
649           g_libcompress_scratchbuf_type = compression_type;
650         }
651       }
652 
653       if (compression_type == compression_types::lz4) {
654         compressed_size = compression_encode_buffer(
655             encoded_data.data(), encoded_data_buf_size,
656             (const uint8_t *)orig.c_str(), orig.size(),
657             g_libcompress_scratchbuf,
658             COMPRESSION_LZ4_RAW);
659       }
660       if (compression_type == compression_types::zlib_deflate) {
661         compressed_size = compression_encode_buffer(
662             encoded_data.data(), encoded_data_buf_size,
663             (const uint8_t *)orig.c_str(), orig.size(),
664             g_libcompress_scratchbuf,
665             COMPRESSION_ZLIB);
666       }
667       if (compression_type == compression_types::lzma) {
668         compressed_size = compression_encode_buffer(
669             encoded_data.data(), encoded_data_buf_size,
670             (const uint8_t *)orig.c_str(), orig.size(),
671             g_libcompress_scratchbuf,
672             COMPRESSION_LZMA);
673       }
674       if (compression_type == compression_types::lzfse) {
675         compressed_size = compression_encode_buffer(
676             encoded_data.data(), encoded_data_buf_size,
677             (const uint8_t *)orig.c_str(), orig.size(),
678             g_libcompress_scratchbuf,
679             COMPRESSION_LZFSE);
680       }
681 
682       if (compressed_size > 0) {
683         compressed.clear();
684         compressed.reserve(compressed_size);
685         compressed = "C";
686         char numbuf[16];
687         snprintf(numbuf, sizeof(numbuf), "%zu:", orig.size());
688         numbuf[sizeof(numbuf) - 1] = '\0';
689         compressed.append(numbuf);
690 
691         for (size_t i = 0; i < compressed_size; i++) {
692           uint8_t byte = encoded_data[i];
693           if (byte == '#' || byte == '$' || byte == '}' || byte == '*' ||
694               byte == '\0') {
695             compressed.push_back(0x7d);
696             compressed.push_back(byte ^ 0x20);
697           } else {
698             compressed.push_back(byte);
699           }
700         }
701       } else {
702         compressed = "N" + orig;
703       }
704     } else {
705       compressed = "N" + orig;
706     }
707   } else {
708     compressed = orig;
709   }
710 
711   return compressed;
712 }
713 
714 rnb_err_t RNBRemote::SendPacket(const std::string &s) {
715   DNBLogThreadedIf(LOG_RNB_MAX, "%8d RNBRemote::%s (%s) called",
716                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
717                    __FUNCTION__, s.c_str());
718 
719   std::string s_compressed = CompressString(s);
720 
721   std::string sendpacket = "$" + s_compressed + "#";
722   int cksum = 0;
723   char hexbuf[5];
724 
725   if (m_noack_mode) {
726     sendpacket += "00";
727   } else {
728     for (size_t i = 0; i != s_compressed.size(); ++i)
729       cksum += s_compressed[i];
730     snprintf(hexbuf, sizeof hexbuf, "%02x", cksum & 0xff);
731     sendpacket += hexbuf;
732   }
733 
734   rnb_err_t err = m_comm.Write(sendpacket.c_str(), sendpacket.size());
735   if (err != rnb_success)
736     return err;
737 
738   if (m_noack_mode)
739     return rnb_success;
740 
741   std::string reply;
742   RNBRemote::Packet packet;
743   err = GetPacket(reply, packet, true);
744 
745   if (err != rnb_success) {
746     DNBLogThreadedIf(LOG_RNB_REMOTE,
747                      "%8d RNBRemote::%s (%s) got error trying to get reply...",
748                      (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
749                      __FUNCTION__, sendpacket.c_str());
750     return err;
751   }
752 
753   DNBLogThreadedIf(LOG_RNB_MAX, "%8d RNBRemote::%s (%s) got reply: '%s'",
754                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
755                    __FUNCTION__, sendpacket.c_str(), reply.c_str());
756 
757   if (packet.type == ack)
758     return rnb_success;
759 
760   // Should we try to resend the packet at this layer?
761   //  if (packet.command == nack)
762   return rnb_err;
763 }
764 
765 /* Get a packet via gdb remote protocol.
766  Strip off the prefix/suffix, verify the checksum to make sure
767  a valid packet was received, send an ACK if they match.  */
768 
769 rnb_err_t RNBRemote::GetPacketPayload(std::string &return_packet) {
770   // DNBLogThreadedIf (LOG_RNB_MAX, "%8u RNBRemote::%s called",
771   // (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__);
772 
773   PThreadMutex::Locker locker(m_mutex);
774   if (m_rx_packets.empty()) {
775     // Only reset the remote command available event if we have no more packets
776     m_ctx.Events().ResetEvents(RNBContext::event_read_packet_available);
777     // DNBLogThreadedIf (LOG_RNB_MAX, "%8u RNBRemote::%s error: no packets
778     // available...", (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
779     // __FUNCTION__);
780     return rnb_err;
781   }
782 
783   // DNBLogThreadedIf (LOG_RNB_MAX, "%8u RNBRemote::%s has %u queued packets",
784   // (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__,
785   // m_rx_packets.size());
786   return_packet.swap(m_rx_packets.front());
787   m_rx_packets.pop_front();
788   locker.Reset(); // Release our lock on the mutex
789 
790   if (m_rx_packets.empty()) {
791     // Reset the remote command available event if we have no more packets
792     m_ctx.Events().ResetEvents(RNBContext::event_read_packet_available);
793   }
794 
795   // DNBLogThreadedIf (LOG_RNB_MEDIUM, "%8u RNBRemote::%s: '%s'",
796   // (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__,
797   // return_packet.c_str());
798 
799   switch (return_packet[0]) {
800   case '+':
801   case '-':
802   case '\x03':
803     break;
804 
805   case '$': {
806     long packet_checksum = 0;
807     if (!m_noack_mode) {
808       for (size_t i = return_packet.size() - 2; i < return_packet.size(); ++i) {
809         char checksum_char = tolower(return_packet[i]);
810         if (!isxdigit(checksum_char)) {
811           m_comm.Write("-", 1);
812           DNBLogThreadedIf(LOG_RNB_REMOTE, "%8u RNBRemote::%s error: packet "
813                                            "with invalid checksum characters: "
814                                            "%s",
815                            (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
816                            __FUNCTION__, return_packet.c_str());
817           return rnb_err;
818         }
819       }
820       packet_checksum =
821           strtol(&return_packet[return_packet.size() - 2], NULL, 16);
822     }
823 
824     return_packet.erase(0, 1);                     // Strip the leading '$'
825     return_packet.erase(return_packet.size() - 3); // Strip the #XX checksum
826 
827     if (!m_noack_mode) {
828       // Compute the checksum
829       int computed_checksum = 0;
830       for (std::string::iterator it = return_packet.begin();
831            it != return_packet.end(); ++it) {
832         computed_checksum += *it;
833       }
834 
835       if (packet_checksum == (computed_checksum & 0xff)) {
836         // DNBLogThreadedIf (LOG_RNB_MEDIUM, "%8u RNBRemote::%s sending ACK for
837         // '%s'", (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
838         // __FUNCTION__, return_packet.c_str());
839         m_comm.Write("+", 1);
840       } else {
841         DNBLogThreadedIf(
842             LOG_RNB_MEDIUM, "%8u RNBRemote::%s sending ACK for '%s' (error: "
843                             "packet checksum mismatch  (0x%2.2lx != 0x%2.2x))",
844             (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__,
845             return_packet.c_str(), packet_checksum, computed_checksum);
846         m_comm.Write("-", 1);
847         return rnb_err;
848       }
849     }
850   } break;
851 
852   default:
853     DNBLogThreadedIf(LOG_RNB_REMOTE,
854                      "%8u RNBRemote::%s tossing unexpected packet???? %s",
855                      (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
856                      __FUNCTION__, return_packet.c_str());
857     if (!m_noack_mode)
858       m_comm.Write("-", 1);
859     return rnb_err;
860   }
861 
862   return rnb_success;
863 }
864 
865 rnb_err_t RNBRemote::HandlePacket_UNIMPLEMENTED(const char *p) {
866   DNBLogThreadedIf(LOG_RNB_MAX, "%8u RNBRemote::%s(\"%s\")",
867                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
868                    __FUNCTION__, p ? p : "NULL");
869   return SendPacket("");
870 }
871 
872 rnb_err_t RNBRemote::HandlePacket_ILLFORMED(const char *file, int line,
873                                             const char *p,
874                                             const char *description) {
875   DNBLogThreadedIf(LOG_RNB_PACKETS, "%8u %s:%i ILLFORMED: '%s' (%s)",
876                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), file,
877                    line, __FUNCTION__, p);
878   return SendPacket("E03");
879 }
880 
881 rnb_err_t RNBRemote::GetPacket(std::string &packet_payload,
882                                RNBRemote::Packet &packet_info, bool wait) {
883   std::string payload;
884   rnb_err_t err = GetPacketPayload(payload);
885   if (err != rnb_success) {
886     PThreadEvent &events = m_ctx.Events();
887     nub_event_t set_events = events.GetEventBits();
888     // TODO: add timeout version of GetPacket?? We would then need to pass
889     // that timeout value along to DNBProcessTimedWaitForEvent.
890     if (!wait || ((set_events & RNBContext::event_read_thread_running) == 0))
891       return err;
892 
893     const nub_event_t events_to_wait_for =
894         RNBContext::event_read_packet_available |
895         RNBContext::event_read_thread_exiting;
896 
897     while ((set_events = events.WaitForSetEvents(events_to_wait_for)) != 0) {
898       if (set_events & RNBContext::event_read_packet_available) {
899         // Try the queue again now that we got an event
900         err = GetPacketPayload(payload);
901         if (err == rnb_success)
902           break;
903       }
904 
905       if (set_events & RNBContext::event_read_thread_exiting)
906         err = rnb_not_connected;
907 
908       if (err == rnb_not_connected)
909         return err;
910     }
911     while (err == rnb_err)
912       ;
913 
914     if (set_events == 0)
915       err = rnb_not_connected;
916   }
917 
918   if (err == rnb_success) {
919     Packet::iterator it;
920     for (it = m_packets.begin(); it != m_packets.end(); ++it) {
921       if (payload.compare(0, it->abbrev.size(), it->abbrev) == 0)
922         break;
923     }
924 
925     // A packet we don't have an entry for. This can happen when we
926     // get a packet that we don't know about or support. We just reply
927     // accordingly and go on.
928     if (it == m_packets.end()) {
929       DNBLogThreadedIf(LOG_RNB_PACKETS, "unimplemented packet: '%s'",
930                        payload.c_str());
931       HandlePacket_UNIMPLEMENTED(payload.c_str());
932       return rnb_err;
933     } else {
934       packet_info = *it;
935       packet_payload = payload;
936     }
937   }
938   return err;
939 }
940 
941 rnb_err_t RNBRemote::HandleAsyncPacket(PacketEnum *type) {
942   DNBLogThreadedIf(LOG_RNB_REMOTE, "%8u RNBRemote::%s",
943                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
944                    __FUNCTION__);
945   static DNBTimer g_packetTimer(true);
946   rnb_err_t err = rnb_err;
947   std::string packet_data;
948   RNBRemote::Packet packet_info;
949   err = GetPacket(packet_data, packet_info, false);
950 
951   if (err == rnb_success) {
952     if (!packet_data.empty() && isprint(packet_data[0]))
953       DNBLogThreadedIf(LOG_RNB_REMOTE | LOG_RNB_PACKETS,
954                        "HandleAsyncPacket (\"%s\");", packet_data.c_str());
955     else
956       DNBLogThreadedIf(LOG_RNB_REMOTE | LOG_RNB_PACKETS,
957                        "HandleAsyncPacket (%s);",
958                        packet_info.printable_name.c_str());
959 
960     HandlePacketCallback packet_callback = packet_info.async;
961     if (packet_callback != NULL) {
962       if (type != NULL)
963         *type = packet_info.type;
964       return (this->*packet_callback)(packet_data.c_str());
965     }
966   }
967 
968   return err;
969 }
970 
971 rnb_err_t RNBRemote::HandleReceivedPacket(PacketEnum *type) {
972   static DNBTimer g_packetTimer(true);
973 
974   //  DNBLogThreadedIf (LOG_RNB_REMOTE, "%8u RNBRemote::%s",
975   //  (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__);
976   rnb_err_t err = rnb_err;
977   std::string packet_data;
978   RNBRemote::Packet packet_info;
979   err = GetPacket(packet_data, packet_info, false);
980 
981   if (err == rnb_success) {
982     DNBLogThreadedIf(LOG_RNB_REMOTE, "HandleReceivedPacket (\"%s\");",
983                      packet_data.c_str());
984     HandlePacketCallback packet_callback = packet_info.normal;
985     if (packet_callback != NULL) {
986       if (type != NULL)
987         *type = packet_info.type;
988       return (this->*packet_callback)(packet_data.c_str());
989     } else {
990       // Do not fall through to end of this function, if we have valid
991       // packet_info and it has a NULL callback, then we need to respect
992       // that it may not want any response or anything to be done.
993       return err;
994     }
995   }
996   return rnb_err;
997 }
998 
999 void RNBRemote::CommDataReceived(const std::string &new_data) {
1000   //  DNBLogThreadedIf (LOG_RNB_REMOTE, "%8d RNBRemote::%s called",
1001   //  (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__);
1002   {
1003     // Put the packet data into the buffer in a thread safe fashion
1004     PThreadMutex::Locker locker(m_mutex);
1005 
1006     std::string data;
1007     // See if we have any left over data from a previous call to this
1008     // function?
1009     if (!m_rx_partial_data.empty()) {
1010       // We do, so lets start with that data
1011       data.swap(m_rx_partial_data);
1012     }
1013     // Append the new incoming data
1014     data += new_data;
1015 
1016     // Parse up the packets into gdb remote packets
1017     size_t idx = 0;
1018     const size_t data_size = data.size();
1019 
1020     while (idx < data_size) {
1021       // end_idx must be one past the last valid packet byte. Start
1022       // it off with an invalid value that is the same as the current
1023       // index.
1024       size_t end_idx = idx;
1025 
1026       switch (data[idx]) {
1027       case '+':            // Look for ack
1028       case '-':            // Look for cancel
1029       case '\x03':         // ^C to halt target
1030         end_idx = idx + 1; // The command is one byte long...
1031         break;
1032 
1033       case '$':
1034         // Look for a standard gdb packet?
1035         end_idx = data.find('#', idx + 1);
1036         if (end_idx == std::string::npos || end_idx + 3 > data_size) {
1037           end_idx = std::string::npos;
1038         } else {
1039           // Add two for the checksum bytes and 1 to point to the
1040           // byte just past the end of this packet
1041           end_idx += 3;
1042         }
1043         break;
1044 
1045       default:
1046         break;
1047       }
1048 
1049       if (end_idx == std::string::npos) {
1050         // Not all data may be here for the packet yet, save it for
1051         // next time through this function.
1052         m_rx_partial_data += data.substr(idx);
1053         // DNBLogThreadedIf (LOG_RNB_MAX, "%8d RNBRemote::%s saving data for
1054         // later[%u, npos):
1055         // '%s'",(uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
1056         // __FUNCTION__, idx, m_rx_partial_data.c_str());
1057         idx = end_idx;
1058       } else if (idx < end_idx) {
1059         m_packets_recvd++;
1060         // Hack to get rid of initial '+' ACK???
1061         if (m_packets_recvd == 1 && (end_idx == idx + 1) && data[idx] == '+') {
1062           // DNBLogThreadedIf (LOG_RNB_REMOTE, "%8d RNBRemote::%s throwing first
1063           // ACK away....[%u, npos):
1064           // '+'",(uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
1065           // __FUNCTION__, idx);
1066         } else {
1067           // We have a valid packet...
1068           m_rx_packets.push_back(data.substr(idx, end_idx - idx));
1069           DNBLogThreadedIf(LOG_RNB_PACKETS, "getpkt: %s",
1070                            m_rx_packets.back().c_str());
1071         }
1072         idx = end_idx;
1073       } else {
1074         DNBLogThreadedIf(LOG_RNB_MAX,
1075                          "%8d RNBRemote::%s tossing junk byte at %c",
1076                          (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
1077                          __FUNCTION__, data[idx]);
1078         idx = idx + 1;
1079       }
1080     }
1081   }
1082 
1083   if (!m_rx_packets.empty()) {
1084     // Let the main thread know we have received a packet
1085 
1086     // DNBLogThreadedIf (LOG_RNB_EVENTS, "%8d RNBRemote::%s   called
1087     // events.SetEvent(RNBContext::event_read_packet_available)",
1088     // (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__);
1089     PThreadEvent &events = m_ctx.Events();
1090     events.SetEvents(RNBContext::event_read_packet_available);
1091   }
1092 }
1093 
1094 rnb_err_t RNBRemote::GetCommData() {
1095   //  DNBLogThreadedIf (LOG_RNB_REMOTE, "%8d RNBRemote::%s called",
1096   //  (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__);
1097   std::string comm_data;
1098   rnb_err_t err = m_comm.Read(comm_data);
1099   if (err == rnb_success) {
1100     if (!comm_data.empty())
1101       CommDataReceived(comm_data);
1102   }
1103   return err;
1104 }
1105 
1106 void RNBRemote::StartReadRemoteDataThread() {
1107   DNBLogThreadedIf(LOG_RNB_REMOTE, "%8u RNBRemote::%s called",
1108                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
1109                    __FUNCTION__);
1110   PThreadEvent &events = m_ctx.Events();
1111   if ((events.GetEventBits() & RNBContext::event_read_thread_running) == 0) {
1112     events.ResetEvents(RNBContext::event_read_thread_exiting);
1113     int err = ::pthread_create(&m_rx_pthread, NULL,
1114                                ThreadFunctionReadRemoteData, this);
1115     if (err == 0) {
1116       // Our thread was successfully kicked off, wait for it to
1117       // set the started event so we can safely continue
1118       events.WaitForSetEvents(RNBContext::event_read_thread_running);
1119     } else {
1120       events.ResetEvents(RNBContext::event_read_thread_running);
1121       events.SetEvents(RNBContext::event_read_thread_exiting);
1122     }
1123   }
1124 }
1125 
1126 void RNBRemote::StopReadRemoteDataThread() {
1127   DNBLogThreadedIf(LOG_RNB_REMOTE, "%8u RNBRemote::%s called",
1128                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
1129                    __FUNCTION__);
1130   PThreadEvent &events = m_ctx.Events();
1131   if ((events.GetEventBits() & RNBContext::event_read_thread_running) ==
1132       RNBContext::event_read_thread_running) {
1133     DNBLog("debugserver about to shut down packet communications to lldb.");
1134     m_comm.Disconnect(true);
1135     struct timespec timeout_abstime;
1136     DNBTimer::OffsetTimeOfDay(&timeout_abstime, 2, 0);
1137 
1138     // Wait for 2 seconds for the remote data thread to exit
1139     if (events.WaitForSetEvents(RNBContext::event_read_thread_exiting,
1140                                 &timeout_abstime) == 0) {
1141       // Kill the remote data thread???
1142     }
1143   }
1144 }
1145 
1146 void *RNBRemote::ThreadFunctionReadRemoteData(void *arg) {
1147   // Keep a shared pointer reference so this doesn't go away on us before the
1148   // thread is killed.
1149   DNBLogThreadedIf(LOG_RNB_REMOTE, "RNBRemote::%s (%p): thread starting...",
1150                    __FUNCTION__, arg);
1151   RNBRemoteSP remoteSP(g_remoteSP);
1152   if (remoteSP.get() != NULL) {
1153 
1154 #if defined(__APPLE__)
1155     pthread_setname_np("read gdb-remote packets thread");
1156 #if defined(__arm__) || defined(__arm64__) || defined(__aarch64__)
1157     struct sched_param thread_param;
1158     int thread_sched_policy;
1159     if (pthread_getschedparam(pthread_self(), &thread_sched_policy,
1160                               &thread_param) == 0) {
1161       thread_param.sched_priority = 47;
1162       pthread_setschedparam(pthread_self(), thread_sched_policy, &thread_param);
1163     }
1164 #endif
1165 #endif
1166 
1167     RNBRemote *remote = remoteSP.get();
1168     PThreadEvent &events = remote->Context().Events();
1169     events.SetEvents(RNBContext::event_read_thread_running);
1170     // START: main receive remote command thread loop
1171     bool done = false;
1172     while (!done) {
1173       rnb_err_t err = remote->GetCommData();
1174 
1175       switch (err) {
1176       case rnb_success:
1177         break;
1178 
1179       case rnb_err:
1180         DNBLogThreadedIf(LOG_RNB_REMOTE,
1181                          "RNBSocket::GetCommData returned error %u", err);
1182         done = true;
1183         break;
1184 
1185       case rnb_not_connected:
1186         DNBLogThreadedIf(LOG_RNB_REMOTE,
1187                          "RNBSocket::GetCommData returned not connected...");
1188         done = true;
1189         break;
1190       }
1191     }
1192     // START: main receive remote command thread loop
1193     events.ResetEvents(RNBContext::event_read_thread_running);
1194     events.SetEvents(RNBContext::event_read_thread_exiting);
1195   }
1196   DNBLogThreadedIf(LOG_RNB_REMOTE, "RNBRemote::%s (%p): thread exiting...",
1197                    __FUNCTION__, arg);
1198   return NULL;
1199 }
1200 
1201 // If we fail to get back a valid CPU type for the remote process,
1202 // make a best guess for the CPU type based on the currently running
1203 // debugserver binary -- the debugger may not handle the case of an
1204 // un-specified process CPU type correctly.
1205 
1206 static cpu_type_t best_guess_cpu_type() {
1207 #if defined(__arm__) || defined(__arm64__) || defined(__aarch64__)
1208   if (sizeof(char *) == 8) {
1209     return CPU_TYPE_ARM64;
1210   } else {
1211 #if defined (__ARM64_ARCH_8_32__)
1212     return CPU_TYPE_ARM64_32;
1213 #endif
1214     return CPU_TYPE_ARM;
1215   }
1216 #elif defined(__i386__) || defined(__x86_64__)
1217   if (sizeof(char *) == 8) {
1218     return CPU_TYPE_X86_64;
1219   } else {
1220     return CPU_TYPE_I386;
1221   }
1222 #endif
1223   return 0;
1224 }
1225 
1226 /* Read the bytes in STR which are GDB Remote Protocol binary encoded bytes
1227  (8-bit bytes).
1228  This encoding uses 0x7d ('}') as an escape character for
1229  0x7d ('}'), 0x23 ('#'), 0x24 ('$'), 0x2a ('*').
1230  LEN is the number of bytes to be processed.  If a character is escaped,
1231  it is 2 characters for LEN.  A LEN of -1 means decode-until-nul-byte
1232  (end of string).  */
1233 
1234 std::vector<uint8_t> decode_binary_data(const char *str, size_t len) {
1235   std::vector<uint8_t> bytes;
1236   if (len == 0) {
1237     return bytes;
1238   }
1239   if (len == (size_t)-1)
1240     len = strlen(str);
1241 
1242   while (len--) {
1243     unsigned char c = *str++;
1244     if (c == 0x7d && len > 0) {
1245       len--;
1246       c = *str++ ^ 0x20;
1247     }
1248     bytes.push_back(c);
1249   }
1250   return bytes;
1251 }
1252 
1253 // Quote any meta characters in a std::string as per the binary
1254 // packet convention in the gdb-remote protocol.
1255 
1256 static std::string binary_encode_string(const std::string &s) {
1257   std::string output;
1258   const size_t s_size = s.size();
1259   const char *s_chars = s.c_str();
1260 
1261   for (size_t i = 0; i < s_size; i++) {
1262     unsigned char ch = *(s_chars + i);
1263     if (ch == '#' || ch == '$' || ch == '}' || ch == '*') {
1264       output.push_back('}'); // 0x7d
1265       output.push_back(ch ^ 0x20);
1266     } else {
1267       output.push_back(ch);
1268     }
1269   }
1270   return output;
1271 }
1272 
1273 // If the value side of a key-value pair in JSON is a string,
1274 // and that string has a " character in it, the " character must
1275 // be escaped.
1276 
1277 std::string json_string_quote_metachars(const std::string &s) {
1278   if (s.find('"') == std::string::npos)
1279     return s;
1280 
1281   std::string output;
1282   const size_t s_size = s.size();
1283   const char *s_chars = s.c_str();
1284   for (size_t i = 0; i < s_size; i++) {
1285     unsigned char ch = *(s_chars + i);
1286     if (ch == '"') {
1287       output.push_back('\\');
1288     }
1289     output.push_back(ch);
1290   }
1291   return output;
1292 }
1293 
1294 typedef struct register_map_entry {
1295   uint32_t debugserver_regnum; // debugserver register number
1296   uint32_t offset; // Offset in bytes into the register context data with no
1297                    // padding between register values
1298   DNBRegisterInfo nub_info; // debugnub register info
1299   std::vector<uint32_t> value_regnums;
1300   std::vector<uint32_t> invalidate_regnums;
1301 } register_map_entry_t;
1302 
1303 // If the notion of registers differs from what is handed out by the
1304 // architecture, then flavors can be defined here.
1305 
1306 static std::vector<register_map_entry_t> g_dynamic_register_map;
1307 static register_map_entry_t *g_reg_entries = NULL;
1308 static size_t g_num_reg_entries = 0;
1309 
1310 void RNBRemote::Initialize() { DNBInitialize(); }
1311 
1312 bool RNBRemote::InitializeRegisters(bool force) {
1313   pid_t pid = m_ctx.ProcessID();
1314   if (pid == INVALID_NUB_PROCESS)
1315     return false;
1316 
1317   DNBLogThreadedIf(
1318       LOG_RNB_PROC,
1319       "RNBRemote::%s() getting native registers from DNB interface",
1320       __FUNCTION__);
1321   // Discover the registers by querying the DNB interface and letting it
1322   // state the registers that it would like to export. This allows the
1323   // registers to be discovered using multiple qRegisterInfo calls to get
1324   // all register information after the architecture for the process is
1325   // determined.
1326   if (force) {
1327     g_dynamic_register_map.clear();
1328     g_reg_entries = NULL;
1329     g_num_reg_entries = 0;
1330   }
1331 
1332   if (g_dynamic_register_map.empty()) {
1333     nub_size_t num_reg_sets = 0;
1334     const DNBRegisterSetInfo *reg_sets = DNBGetRegisterSetInfo(&num_reg_sets);
1335 
1336     assert(num_reg_sets > 0 && reg_sets != NULL);
1337 
1338     uint32_t regnum = 0;
1339     uint32_t reg_data_offset = 0;
1340     typedef std::map<std::string, uint32_t> NameToRegNum;
1341     NameToRegNum name_to_regnum;
1342     for (nub_size_t set = 0; set < num_reg_sets; ++set) {
1343       if (reg_sets[set].registers == NULL)
1344         continue;
1345 
1346       for (uint32_t reg = 0; reg < reg_sets[set].num_registers; ++reg) {
1347         register_map_entry_t reg_entry = {
1348             regnum++, // register number starts at zero and goes up with no gaps
1349             reg_data_offset, // Offset into register context data, no gaps
1350                              // between registers
1351             reg_sets[set].registers[reg], // DNBRegisterInfo
1352             {},
1353             {},
1354         };
1355 
1356         name_to_regnum[reg_entry.nub_info.name] = reg_entry.debugserver_regnum;
1357 
1358         if (reg_entry.nub_info.value_regs == NULL) {
1359           reg_data_offset += reg_entry.nub_info.size;
1360         }
1361 
1362         g_dynamic_register_map.push_back(reg_entry);
1363       }
1364     }
1365 
1366     // Now we must find any registers whose values are in other registers and
1367     // fix up
1368     // the offsets since we removed all gaps...
1369     for (auto &reg_entry : g_dynamic_register_map) {
1370       if (reg_entry.nub_info.value_regs) {
1371         uint32_t new_offset = UINT32_MAX;
1372         for (size_t i = 0; reg_entry.nub_info.value_regs[i] != NULL; ++i) {
1373           const char *name = reg_entry.nub_info.value_regs[i];
1374           auto pos = name_to_regnum.find(name);
1375           if (pos != name_to_regnum.end()) {
1376             regnum = pos->second;
1377             reg_entry.value_regnums.push_back(regnum);
1378             if (regnum < g_dynamic_register_map.size()) {
1379               // The offset for value_regs registers is the offset within the
1380               // register with the lowest offset
1381               const uint32_t reg_offset =
1382                   g_dynamic_register_map[regnum].offset +
1383                   reg_entry.nub_info.offset;
1384               if (new_offset > reg_offset)
1385                 new_offset = reg_offset;
1386             }
1387           }
1388         }
1389 
1390         if (new_offset != UINT32_MAX) {
1391           reg_entry.offset = new_offset;
1392         } else {
1393           DNBLogThreaded("no offset was calculated entry for register %s",
1394                          reg_entry.nub_info.name);
1395           reg_entry.offset = UINT32_MAX;
1396         }
1397       }
1398 
1399       if (reg_entry.nub_info.update_regs) {
1400         for (size_t i = 0; reg_entry.nub_info.update_regs[i] != NULL; ++i) {
1401           const char *name = reg_entry.nub_info.update_regs[i];
1402           auto pos = name_to_regnum.find(name);
1403           if (pos != name_to_regnum.end()) {
1404             regnum = pos->second;
1405             reg_entry.invalidate_regnums.push_back(regnum);
1406           }
1407         }
1408       }
1409     }
1410 
1411     //        for (auto &reg_entry: g_dynamic_register_map)
1412     //        {
1413     //            DNBLogThreaded("%4i: size = %3u, pseudo = %i, name = %s",
1414     //                           reg_entry.offset,
1415     //                           reg_entry.nub_info.size,
1416     //                           reg_entry.nub_info.value_regs != NULL,
1417     //                           reg_entry.nub_info.name);
1418     //        }
1419 
1420     g_reg_entries = g_dynamic_register_map.data();
1421     g_num_reg_entries = g_dynamic_register_map.size();
1422   }
1423   return true;
1424 }
1425 
1426 /* The inferior has stopped executing; send a packet
1427  to gdb to let it know.  */
1428 
1429 void RNBRemote::NotifyThatProcessStopped(void) {
1430   RNBRemote::HandlePacket_last_signal(NULL);
1431   return;
1432 }
1433 
1434 /* 'A arglen,argnum,arg,...'
1435  Update the inferior context CTX with the program name and arg
1436  list.
1437  The documentation for this packet is underwhelming but my best reading
1438  of this is that it is a series of (len, position #, arg)'s, one for
1439  each argument with "arg" hex encoded (two 0-9a-f chars?).
1440  Why we need BOTH a "len" and a hex encoded "arg" is beyond me - either
1441  is sufficient to get around the "," position separator escape issue.
1442 
1443  e.g. our best guess for a valid 'A' packet for "gdb -q a.out" is
1444 
1445  6,0,676462,4,1,2d71,10,2,612e6f7574
1446 
1447  Note that "argnum" and "arglen" are numbers in base 10.  Again, that's
1448  not documented either way but I'm assuming it's so.  */
1449 
1450 rnb_err_t RNBRemote::HandlePacket_A(const char *p) {
1451   if (p == NULL || *p == '\0') {
1452     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1453                                   "Null packet for 'A' pkt");
1454   }
1455   p++;
1456   if (*p == '\0' || !isdigit(*p)) {
1457     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1458                                   "arglen not specified on 'A' pkt");
1459   }
1460 
1461   /* I promise I don't modify it anywhere in this function.  strtoul()'s
1462    2nd arg has to be non-const which makes it problematic to step
1463    through the string easily.  */
1464   char *buf = const_cast<char *>(p);
1465 
1466   RNBContext &ctx = Context();
1467 
1468   while (*buf != '\0') {
1469     unsigned long arglen, argnum;
1470     std::string arg;
1471     char *c;
1472 
1473     errno = 0;
1474     arglen = strtoul(buf, &c, 10);
1475     if (errno != 0 && arglen == 0) {
1476       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1477                                     "arglen not a number on 'A' pkt");
1478     }
1479     if (*c != ',') {
1480       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1481                                     "arglen not followed by comma on 'A' pkt");
1482     }
1483     buf = c + 1;
1484 
1485     errno = 0;
1486     argnum = strtoul(buf, &c, 10);
1487     if (errno != 0 && argnum == 0) {
1488       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1489                                     "argnum not a number on 'A' pkt");
1490     }
1491     if (*c != ',') {
1492       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1493                                     "arglen not followed by comma on 'A' pkt");
1494     }
1495     buf = c + 1;
1496 
1497     c = buf;
1498     buf = buf + arglen;
1499     while (c < buf && *c != '\0' && c + 1 < buf && *(c + 1) != '\0') {
1500       char smallbuf[3];
1501       smallbuf[0] = *c;
1502       smallbuf[1] = *(c + 1);
1503       smallbuf[2] = '\0';
1504 
1505       errno = 0;
1506       int ch = static_cast<int>(strtoul(smallbuf, NULL, 16));
1507       if (errno != 0 && ch == 0) {
1508         return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1509                                       "non-hex char in arg on 'A' pkt");
1510       }
1511 
1512       arg.push_back(ch);
1513       c += 2;
1514     }
1515 
1516     ctx.PushArgument(arg.c_str());
1517     if (*buf == ',')
1518       buf++;
1519   }
1520   SendPacket("OK");
1521 
1522   return rnb_success;
1523 }
1524 
1525 /* 'H c t'
1526  Set the thread for subsequent actions; 'c' for step/continue ops,
1527  'g' for other ops.  -1 means all threads, 0 means any thread.  */
1528 
1529 rnb_err_t RNBRemote::HandlePacket_H(const char *p) {
1530   p++; // skip 'H'
1531   if (*p != 'c' && *p != 'g') {
1532     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1533                                   "Missing 'c' or 'g' type in H packet");
1534   }
1535 
1536   if (!m_ctx.HasValidProcessID()) {
1537     // We allow gdb to connect to a server that hasn't started running
1538     // the target yet.  gdb still wants to ask questions about it and
1539     // freaks out if it gets an error.  So just return OK here.
1540   }
1541 
1542   errno = 0;
1543   nub_thread_t tid = strtoul(p + 1, NULL, 16);
1544   if (errno != 0 && tid == 0) {
1545     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1546                                   "Invalid thread number in H packet");
1547   }
1548   if (*p == 'c')
1549     SetContinueThread(tid);
1550   if (*p == 'g')
1551     SetCurrentThread(tid);
1552 
1553   return SendPacket("OK");
1554 }
1555 
1556 rnb_err_t RNBRemote::HandlePacket_qLaunchSuccess(const char *p) {
1557   if (m_ctx.HasValidProcessID() || m_ctx.LaunchStatus().Status() == 0)
1558     return SendPacket("OK");
1559   std::ostringstream ret_str;
1560   std::string status_str;
1561   std::string error_quoted = binary_encode_string
1562                (m_ctx.LaunchStatusAsString(status_str));
1563   ret_str << "E" << error_quoted;
1564 
1565   return SendPacket(ret_str.str());
1566 }
1567 
1568 rnb_err_t RNBRemote::HandlePacket_qShlibInfoAddr(const char *p) {
1569   if (m_ctx.HasValidProcessID()) {
1570     nub_addr_t shlib_info_addr =
1571         DNBProcessGetSharedLibraryInfoAddress(m_ctx.ProcessID());
1572     if (shlib_info_addr != INVALID_NUB_ADDRESS) {
1573       std::ostringstream ostrm;
1574       ostrm << RAW_HEXBASE << shlib_info_addr;
1575       return SendPacket(ostrm.str());
1576     }
1577   }
1578   return SendPacket("E44");
1579 }
1580 
1581 rnb_err_t RNBRemote::HandlePacket_qStepPacketSupported(const char *p) {
1582   // Normally the "s" packet is mandatory, yet in gdb when using ARM, they
1583   // get around the need for this packet by implementing software single
1584   // stepping from gdb. Current versions of debugserver do support the "s"
1585   // packet, yet some older versions do not. We need a way to tell if this
1586   // packet is supported so we can disable software single stepping in gdb
1587   // for remote targets (so the "s" packet will get used).
1588   return SendPacket("OK");
1589 }
1590 
1591 rnb_err_t RNBRemote::HandlePacket_qSyncThreadStateSupported(const char *p) {
1592   // We support attachOrWait meaning attach if the process exists, otherwise
1593   // wait to attach.
1594   return SendPacket("OK");
1595 }
1596 
1597 rnb_err_t RNBRemote::HandlePacket_qVAttachOrWaitSupported(const char *p) {
1598   // We support attachOrWait meaning attach if the process exists, otherwise
1599   // wait to attach.
1600   return SendPacket("OK");
1601 }
1602 
1603 rnb_err_t RNBRemote::HandlePacket_qThreadStopInfo(const char *p) {
1604   p += strlen("qThreadStopInfo");
1605   nub_thread_t tid = strtoul(p, 0, 16);
1606   return SendStopReplyPacketForThread(tid);
1607 }
1608 
1609 rnb_err_t RNBRemote::HandlePacket_qThreadInfo(const char *p) {
1610   // We allow gdb to connect to a server that hasn't started running
1611   // the target yet.  gdb still wants to ask questions about it and
1612   // freaks out if it gets an error.  So just return OK here.
1613   nub_process_t pid = m_ctx.ProcessID();
1614   if (pid == INVALID_NUB_PROCESS)
1615     return SendPacket("OK");
1616 
1617   // Only "qfThreadInfo" and "qsThreadInfo" get into this function so
1618   // we only need to check the second byte to tell which is which
1619   if (p[1] == 'f') {
1620     nub_size_t numthreads = DNBProcessGetNumThreads(pid);
1621     std::ostringstream ostrm;
1622     ostrm << "m";
1623     bool first = true;
1624     for (nub_size_t i = 0; i < numthreads; ++i) {
1625       if (first)
1626         first = false;
1627       else
1628         ostrm << ",";
1629       nub_thread_t th = DNBProcessGetThreadAtIndex(pid, i);
1630       ostrm << std::hex << th;
1631     }
1632     return SendPacket(ostrm.str());
1633   } else {
1634     return SendPacket("l");
1635   }
1636 }
1637 
1638 rnb_err_t RNBRemote::HandlePacket_qThreadExtraInfo(const char *p) {
1639   // We allow gdb to connect to a server that hasn't started running
1640   // the target yet.  gdb still wants to ask questions about it and
1641   // freaks out if it gets an error.  So just return OK here.
1642   nub_process_t pid = m_ctx.ProcessID();
1643   if (pid == INVALID_NUB_PROCESS)
1644     return SendPacket("OK");
1645 
1646   /* This is supposed to return a string like 'Runnable' or
1647    'Blocked on Mutex'.
1648    The returned string is formatted like the "A" packet - a
1649    sequence of letters encoded in as 2-hex-chars-per-letter.  */
1650   p += strlen("qThreadExtraInfo");
1651   if (*p++ != ',')
1652     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1653                                   "Illformed qThreadExtraInfo packet");
1654   errno = 0;
1655   nub_thread_t tid = strtoul(p, NULL, 16);
1656   if (errno != 0 && tid == 0) {
1657     return HandlePacket_ILLFORMED(
1658         __FILE__, __LINE__, p,
1659         "Invalid thread number in qThreadExtraInfo packet");
1660   }
1661 
1662   const char *threadInfo = DNBThreadGetInfo(pid, tid);
1663   if (threadInfo != NULL && threadInfo[0]) {
1664     return SendHexEncodedBytePacket(NULL, threadInfo, strlen(threadInfo), NULL);
1665   } else {
1666     // "OK" == 4f6b
1667     // Return "OK" as a ASCII hex byte stream if things go wrong
1668     return SendPacket("4f6b");
1669   }
1670 
1671   return SendPacket("");
1672 }
1673 
1674 const char *k_space_delimiters = " \t";
1675 static void skip_spaces(std::string &line) {
1676   if (!line.empty()) {
1677     size_t space_pos = line.find_first_not_of(k_space_delimiters);
1678     if (space_pos > 0)
1679       line.erase(0, space_pos);
1680   }
1681 }
1682 
1683 static std::string get_identifier(std::string &line) {
1684   std::string word;
1685   skip_spaces(line);
1686   const size_t line_size = line.size();
1687   size_t end_pos;
1688   for (end_pos = 0; end_pos < line_size; ++end_pos) {
1689     if (end_pos == 0) {
1690       if (isalpha(line[end_pos]) || line[end_pos] == '_')
1691         continue;
1692     } else if (isalnum(line[end_pos]) || line[end_pos] == '_')
1693       continue;
1694     break;
1695   }
1696   word.assign(line, 0, end_pos);
1697   line.erase(0, end_pos);
1698   return word;
1699 }
1700 
1701 static std::string get_operator(std::string &line) {
1702   std::string op;
1703   skip_spaces(line);
1704   if (!line.empty()) {
1705     if (line[0] == '=') {
1706       op = '=';
1707       line.erase(0, 1);
1708     }
1709   }
1710   return op;
1711 }
1712 
1713 static std::string get_value(std::string &line) {
1714   std::string value;
1715   skip_spaces(line);
1716   if (!line.empty()) {
1717     value.swap(line);
1718   }
1719   return value;
1720 }
1721 
1722 extern void FileLogCallback(void *baton, uint32_t flags, const char *format,
1723                             va_list args);
1724 extern void ASLLogCallback(void *baton, uint32_t flags, const char *format,
1725                            va_list args);
1726 
1727 rnb_err_t RNBRemote::HandlePacket_qRcmd(const char *p) {
1728   const char *c = p + strlen("qRcmd,");
1729   std::string line;
1730   while (c[0] && c[1]) {
1731     char smallbuf[3] = {c[0], c[1], '\0'};
1732     errno = 0;
1733     int ch = static_cast<int>(strtoul(smallbuf, NULL, 16));
1734     if (errno != 0 && ch == 0)
1735       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
1736                                     "non-hex char in payload of qRcmd packet");
1737     line.push_back(ch);
1738     c += 2;
1739   }
1740   if (*c == '\0') {
1741     std::string command = get_identifier(line);
1742     if (command == "set") {
1743       std::string variable = get_identifier(line);
1744       std::string op = get_operator(line);
1745       std::string value = get_value(line);
1746       if (variable == "logfile") {
1747         FILE *log_file = fopen(value.c_str(), "w");
1748         if (log_file) {
1749           DNBLogSetLogCallback(FileLogCallback, log_file);
1750           return SendPacket("OK");
1751         }
1752         return SendPacket("E71");
1753       } else if (variable == "logmask") {
1754         char *end;
1755         errno = 0;
1756         uint32_t logmask =
1757             static_cast<uint32_t>(strtoul(value.c_str(), &end, 0));
1758         if (errno == 0 && end && *end == '\0') {
1759           DNBLogSetLogMask(logmask);
1760           if (!DNBLogGetLogCallback())
1761             DNBLogSetLogCallback(ASLLogCallback, NULL);
1762           return SendPacket("OK");
1763         }
1764         errno = 0;
1765         logmask = static_cast<uint32_t>(strtoul(value.c_str(), &end, 16));
1766         if (errno == 0 && end && *end == '\0') {
1767           DNBLogSetLogMask(logmask);
1768           return SendPacket("OK");
1769         }
1770         return SendPacket("E72");
1771       }
1772       return SendPacket("E70");
1773     }
1774     return SendPacket("E69");
1775   }
1776   return SendPacket("E73");
1777 }
1778 
1779 rnb_err_t RNBRemote::HandlePacket_qC(const char *p) {
1780   nub_thread_t tid;
1781   std::ostringstream rep;
1782   // If we haven't run the process yet, we tell the debugger the
1783   // pid is 0.  That way it can know to tell use to run later on.
1784   if (!m_ctx.HasValidProcessID())
1785     tid = 0;
1786   else {
1787     // Grab the current thread.
1788     tid = DNBProcessGetCurrentThread(m_ctx.ProcessID());
1789     // Make sure we set the current thread so g and p packets return
1790     // the data the gdb will expect.
1791     SetCurrentThread(tid);
1792   }
1793   rep << "QC" << std::hex << tid;
1794   return SendPacket(rep.str());
1795 }
1796 
1797 rnb_err_t RNBRemote::HandlePacket_qEcho(const char *p) {
1798   // Just send the exact same packet back that we received to
1799   // synchronize the response packets after a previous packet
1800   // timed out. This allows the debugger to get back on track
1801   // with responses after a packet timeout.
1802   return SendPacket(p);
1803 }
1804 
1805 rnb_err_t RNBRemote::HandlePacket_qGetPid(const char *p) {
1806   nub_process_t pid;
1807   std::ostringstream rep;
1808   // If we haven't run the process yet, we tell the debugger the
1809   // pid is 0.  That way it can know to tell use to run later on.
1810   if (m_ctx.HasValidProcessID())
1811     pid = m_ctx.ProcessID();
1812   else
1813     pid = 0;
1814   rep << std::hex << pid;
1815   return SendPacket(rep.str());
1816 }
1817 
1818 rnb_err_t RNBRemote::HandlePacket_qRegisterInfo(const char *p) {
1819   if (g_num_reg_entries == 0)
1820     InitializeRegisters();
1821 
1822   p += strlen("qRegisterInfo");
1823 
1824   nub_size_t num_reg_sets = 0;
1825   const DNBRegisterSetInfo *reg_set_info = DNBGetRegisterSetInfo(&num_reg_sets);
1826   uint32_t reg_num = static_cast<uint32_t>(strtoul(p, 0, 16));
1827 
1828   if (reg_num < g_num_reg_entries) {
1829     const register_map_entry_t *reg_entry = &g_reg_entries[reg_num];
1830     std::ostringstream ostrm;
1831     if (reg_entry->nub_info.name)
1832       ostrm << "name:" << reg_entry->nub_info.name << ';';
1833     if (reg_entry->nub_info.alt)
1834       ostrm << "alt-name:" << reg_entry->nub_info.alt << ';';
1835 
1836     ostrm << "bitsize:" << std::dec << reg_entry->nub_info.size * 8 << ';';
1837     ostrm << "offset:" << std::dec << reg_entry->offset << ';';
1838 
1839     switch (reg_entry->nub_info.type) {
1840     case Uint:
1841       ostrm << "encoding:uint;";
1842       break;
1843     case Sint:
1844       ostrm << "encoding:sint;";
1845       break;
1846     case IEEE754:
1847       ostrm << "encoding:ieee754;";
1848       break;
1849     case Vector:
1850       ostrm << "encoding:vector;";
1851       break;
1852     }
1853 
1854     switch (reg_entry->nub_info.format) {
1855     case Binary:
1856       ostrm << "format:binary;";
1857       break;
1858     case Decimal:
1859       ostrm << "format:decimal;";
1860       break;
1861     case Hex:
1862       ostrm << "format:hex;";
1863       break;
1864     case Float:
1865       ostrm << "format:float;";
1866       break;
1867     case VectorOfSInt8:
1868       ostrm << "format:vector-sint8;";
1869       break;
1870     case VectorOfUInt8:
1871       ostrm << "format:vector-uint8;";
1872       break;
1873     case VectorOfSInt16:
1874       ostrm << "format:vector-sint16;";
1875       break;
1876     case VectorOfUInt16:
1877       ostrm << "format:vector-uint16;";
1878       break;
1879     case VectorOfSInt32:
1880       ostrm << "format:vector-sint32;";
1881       break;
1882     case VectorOfUInt32:
1883       ostrm << "format:vector-uint32;";
1884       break;
1885     case VectorOfFloat32:
1886       ostrm << "format:vector-float32;";
1887       break;
1888     case VectorOfUInt128:
1889       ostrm << "format:vector-uint128;";
1890       break;
1891     };
1892 
1893     if (reg_set_info && reg_entry->nub_info.set < num_reg_sets)
1894       ostrm << "set:" << reg_set_info[reg_entry->nub_info.set].name << ';';
1895 
1896     if (reg_entry->nub_info.reg_ehframe != INVALID_NUB_REGNUM)
1897       ostrm << "ehframe:" << std::dec << reg_entry->nub_info.reg_ehframe << ';';
1898 
1899     if (reg_entry->nub_info.reg_dwarf != INVALID_NUB_REGNUM)
1900       ostrm << "dwarf:" << std::dec << reg_entry->nub_info.reg_dwarf << ';';
1901 
1902     switch (reg_entry->nub_info.reg_generic) {
1903     case GENERIC_REGNUM_FP:
1904       ostrm << "generic:fp;";
1905       break;
1906     case GENERIC_REGNUM_PC:
1907       ostrm << "generic:pc;";
1908       break;
1909     case GENERIC_REGNUM_SP:
1910       ostrm << "generic:sp;";
1911       break;
1912     case GENERIC_REGNUM_RA:
1913       ostrm << "generic:ra;";
1914       break;
1915     case GENERIC_REGNUM_FLAGS:
1916       ostrm << "generic:flags;";
1917       break;
1918     case GENERIC_REGNUM_ARG1:
1919       ostrm << "generic:arg1;";
1920       break;
1921     case GENERIC_REGNUM_ARG2:
1922       ostrm << "generic:arg2;";
1923       break;
1924     case GENERIC_REGNUM_ARG3:
1925       ostrm << "generic:arg3;";
1926       break;
1927     case GENERIC_REGNUM_ARG4:
1928       ostrm << "generic:arg4;";
1929       break;
1930     case GENERIC_REGNUM_ARG5:
1931       ostrm << "generic:arg5;";
1932       break;
1933     case GENERIC_REGNUM_ARG6:
1934       ostrm << "generic:arg6;";
1935       break;
1936     case GENERIC_REGNUM_ARG7:
1937       ostrm << "generic:arg7;";
1938       break;
1939     case GENERIC_REGNUM_ARG8:
1940       ostrm << "generic:arg8;";
1941       break;
1942     default:
1943       break;
1944     }
1945 
1946     if (!reg_entry->value_regnums.empty()) {
1947       ostrm << "container-regs:";
1948       for (size_t i = 0, n = reg_entry->value_regnums.size(); i < n; ++i) {
1949         if (i > 0)
1950           ostrm << ',';
1951         ostrm << RAW_HEXBASE << reg_entry->value_regnums[i];
1952       }
1953       ostrm << ';';
1954     }
1955 
1956     if (!reg_entry->invalidate_regnums.empty()) {
1957       ostrm << "invalidate-regs:";
1958       for (size_t i = 0, n = reg_entry->invalidate_regnums.size(); i < n; ++i) {
1959         if (i > 0)
1960           ostrm << ',';
1961         ostrm << RAW_HEXBASE << reg_entry->invalidate_regnums[i];
1962       }
1963       ostrm << ';';
1964     }
1965 
1966     return SendPacket(ostrm.str());
1967   }
1968   return SendPacket("E45");
1969 }
1970 
1971 /* This expects a packet formatted like
1972 
1973  QSetLogging:bitmask=LOG_ALL|LOG_RNB_REMOTE;
1974 
1975  with the "QSetLogging:" already removed from the start.  Maybe in the
1976  future this packet will include other keyvalue pairs like
1977 
1978  QSetLogging:bitmask=LOG_ALL;mode=asl;
1979  */
1980 
1981 rnb_err_t set_logging(const char *p) {
1982   int bitmask = 0;
1983   while (p && *p != '\0') {
1984     if (strncmp(p, "bitmask=", sizeof("bitmask=") - 1) == 0) {
1985       p += sizeof("bitmask=") - 1;
1986       while (p && *p != '\0' && *p != ';') {
1987         if (*p == '|')
1988           p++;
1989 
1990         // to regenerate the LOG_ entries (not including the LOG_RNB entries)
1991         // $ for logname in `grep '^#define LOG_' DNBDefs.h | egrep -v
1992         // 'LOG_HI|LOG_LO' | awk '{print $2}'`
1993         // do
1994         //   echo "                else if (strncmp (p, \"$logname\", sizeof
1995         //   (\"$logname\") - 1) == 0)"
1996         //   echo "                {"
1997         //   echo "                    p += sizeof (\"$logname\") - 1;"
1998         //   echo "                    bitmask |= $logname;"
1999         //   echo "                }"
2000         // done
2001         if (strncmp(p, "LOG_VERBOSE", sizeof("LOG_VERBOSE") - 1) == 0) {
2002           p += sizeof("LOG_VERBOSE") - 1;
2003           bitmask |= LOG_VERBOSE;
2004         } else if (strncmp(p, "LOG_PROCESS", sizeof("LOG_PROCESS") - 1) == 0) {
2005           p += sizeof("LOG_PROCESS") - 1;
2006           bitmask |= LOG_PROCESS;
2007         } else if (strncmp(p, "LOG_THREAD", sizeof("LOG_THREAD") - 1) == 0) {
2008           p += sizeof("LOG_THREAD") - 1;
2009           bitmask |= LOG_THREAD;
2010         } else if (strncmp(p, "LOG_EXCEPTIONS", sizeof("LOG_EXCEPTIONS") - 1) ==
2011                    0) {
2012           p += sizeof("LOG_EXCEPTIONS") - 1;
2013           bitmask |= LOG_EXCEPTIONS;
2014         } else if (strncmp(p, "LOG_SHLIB", sizeof("LOG_SHLIB") - 1) == 0) {
2015           p += sizeof("LOG_SHLIB") - 1;
2016           bitmask |= LOG_SHLIB;
2017         } else if (strncmp(p, "LOG_MEMORY_DATA_SHORT",
2018                            sizeof("LOG_MEMORY_DATA_SHORT") - 1) == 0) {
2019           p += sizeof("LOG_MEMORY_DATA_SHORT") - 1;
2020           bitmask |= LOG_MEMORY_DATA_SHORT;
2021         } else if (strncmp(p, "LOG_MEMORY_DATA_LONG",
2022                            sizeof("LOG_MEMORY_DATA_LONG") - 1) == 0) {
2023           p += sizeof("LOG_MEMORY_DATA_LONG") - 1;
2024           bitmask |= LOG_MEMORY_DATA_LONG;
2025         } else if (strncmp(p, "LOG_MEMORY_PROTECTIONS",
2026                            sizeof("LOG_MEMORY_PROTECTIONS") - 1) == 0) {
2027           p += sizeof("LOG_MEMORY_PROTECTIONS") - 1;
2028           bitmask |= LOG_MEMORY_PROTECTIONS;
2029         } else if (strncmp(p, "LOG_MEMORY", sizeof("LOG_MEMORY") - 1) == 0) {
2030           p += sizeof("LOG_MEMORY") - 1;
2031           bitmask |= LOG_MEMORY;
2032         } else if (strncmp(p, "LOG_BREAKPOINTS",
2033                            sizeof("LOG_BREAKPOINTS") - 1) == 0) {
2034           p += sizeof("LOG_BREAKPOINTS") - 1;
2035           bitmask |= LOG_BREAKPOINTS;
2036         } else if (strncmp(p, "LOG_EVENTS", sizeof("LOG_EVENTS") - 1) == 0) {
2037           p += sizeof("LOG_EVENTS") - 1;
2038           bitmask |= LOG_EVENTS;
2039         } else if (strncmp(p, "LOG_WATCHPOINTS",
2040                            sizeof("LOG_WATCHPOINTS") - 1) == 0) {
2041           p += sizeof("LOG_WATCHPOINTS") - 1;
2042           bitmask |= LOG_WATCHPOINTS;
2043         } else if (strncmp(p, "LOG_STEP", sizeof("LOG_STEP") - 1) == 0) {
2044           p += sizeof("LOG_STEP") - 1;
2045           bitmask |= LOG_STEP;
2046         } else if (strncmp(p, "LOG_TASK", sizeof("LOG_TASK") - 1) == 0) {
2047           p += sizeof("LOG_TASK") - 1;
2048           bitmask |= LOG_TASK;
2049         } else if (strncmp(p, "LOG_ALL", sizeof("LOG_ALL") - 1) == 0) {
2050           p += sizeof("LOG_ALL") - 1;
2051           bitmask |= LOG_ALL;
2052         } else if (strncmp(p, "LOG_DEFAULT", sizeof("LOG_DEFAULT") - 1) == 0) {
2053           p += sizeof("LOG_DEFAULT") - 1;
2054           bitmask |= LOG_DEFAULT;
2055         }
2056         // end of auto-generated entries
2057 
2058         else if (strncmp(p, "LOG_NONE", sizeof("LOG_NONE") - 1) == 0) {
2059           p += sizeof("LOG_NONE") - 1;
2060           bitmask = 0;
2061         } else if (strncmp(p, "LOG_RNB_MINIMAL",
2062                            sizeof("LOG_RNB_MINIMAL") - 1) == 0) {
2063           p += sizeof("LOG_RNB_MINIMAL") - 1;
2064           bitmask |= LOG_RNB_MINIMAL;
2065         } else if (strncmp(p, "LOG_RNB_MEDIUM", sizeof("LOG_RNB_MEDIUM") - 1) ==
2066                    0) {
2067           p += sizeof("LOG_RNB_MEDIUM") - 1;
2068           bitmask |= LOG_RNB_MEDIUM;
2069         } else if (strncmp(p, "LOG_RNB_MAX", sizeof("LOG_RNB_MAX") - 1) == 0) {
2070           p += sizeof("LOG_RNB_MAX") - 1;
2071           bitmask |= LOG_RNB_MAX;
2072         } else if (strncmp(p, "LOG_RNB_COMM", sizeof("LOG_RNB_COMM") - 1) ==
2073                    0) {
2074           p += sizeof("LOG_RNB_COMM") - 1;
2075           bitmask |= LOG_RNB_COMM;
2076         } else if (strncmp(p, "LOG_RNB_REMOTE", sizeof("LOG_RNB_REMOTE") - 1) ==
2077                    0) {
2078           p += sizeof("LOG_RNB_REMOTE") - 1;
2079           bitmask |= LOG_RNB_REMOTE;
2080         } else if (strncmp(p, "LOG_RNB_EVENTS", sizeof("LOG_RNB_EVENTS") - 1) ==
2081                    0) {
2082           p += sizeof("LOG_RNB_EVENTS") - 1;
2083           bitmask |= LOG_RNB_EVENTS;
2084         } else if (strncmp(p, "LOG_RNB_PROC", sizeof("LOG_RNB_PROC") - 1) ==
2085                    0) {
2086           p += sizeof("LOG_RNB_PROC") - 1;
2087           bitmask |= LOG_RNB_PROC;
2088         } else if (strncmp(p, "LOG_RNB_PACKETS",
2089                            sizeof("LOG_RNB_PACKETS") - 1) == 0) {
2090           p += sizeof("LOG_RNB_PACKETS") - 1;
2091           bitmask |= LOG_RNB_PACKETS;
2092         } else if (strncmp(p, "LOG_RNB_ALL", sizeof("LOG_RNB_ALL") - 1) == 0) {
2093           p += sizeof("LOG_RNB_ALL") - 1;
2094           bitmask |= LOG_RNB_ALL;
2095         } else if (strncmp(p, "LOG_RNB_DEFAULT",
2096                            sizeof("LOG_RNB_DEFAULT") - 1) == 0) {
2097           p += sizeof("LOG_RNB_DEFAULT") - 1;
2098           bitmask |= LOG_RNB_DEFAULT;
2099         } else if (strncmp(p, "LOG_DARWIN_LOG", sizeof("LOG_DARWIN_LOG") - 1) ==
2100                    0) {
2101           p += sizeof("LOG_DARWIN_LOG") - 1;
2102           bitmask |= LOG_DARWIN_LOG;
2103         } else if (strncmp(p, "LOG_RNB_NONE", sizeof("LOG_RNB_NONE") - 1) ==
2104                    0) {
2105           p += sizeof("LOG_RNB_NONE") - 1;
2106           bitmask = 0;
2107         } else {
2108           /* Unrecognized logging bit; ignore it.  */
2109           const char *c = strchr(p, '|');
2110           if (c) {
2111             p = c;
2112           } else {
2113             c = strchr(p, ';');
2114             if (c) {
2115               p = c;
2116             } else {
2117               // Improperly terminated word; just go to end of str
2118               p = strchr(p, '\0');
2119             }
2120           }
2121         }
2122       }
2123       // Did we get a properly formatted logging bitmask?
2124       if (p && *p == ';') {
2125         // Enable DNB logging.
2126         // Use the existing log callback if one was already configured.
2127         if (!DNBLogGetLogCallback()) {
2128           // Use the os_log()-based logger if available; otherwise,
2129           // fallback to ASL.
2130           auto log_callback = OsLogger::GetLogFunction();
2131           if (log_callback)
2132             DNBLogSetLogCallback(log_callback, nullptr);
2133           else
2134             DNBLogSetLogCallback(ASLLogCallback, nullptr);
2135         }
2136 
2137         // Update logging to use the configured log channel bitmask.
2138         DNBLogSetLogMask(bitmask);
2139         p++;
2140       }
2141     }
2142 // We're not going to support logging to a file for now.  All logging
2143 // goes through ASL or the previously arranged log callback.
2144 #if 0
2145         else if (strncmp (p, "mode=", sizeof ("mode=") - 1) == 0)
2146         {
2147             p += sizeof ("mode=") - 1;
2148             if (strncmp (p, "asl;", sizeof ("asl;") - 1) == 0)
2149             {
2150                 DNBLogToASL ();
2151                 p += sizeof ("asl;") - 1;
2152             }
2153             else if (strncmp (p, "file;", sizeof ("file;") - 1) == 0)
2154             {
2155                 DNBLogToFile ();
2156                 p += sizeof ("file;") - 1;
2157             }
2158             else
2159             {
2160                 // Ignore unknown argument
2161                 const char *c = strchr (p, ';');
2162                 if (c)
2163                     p = c + 1;
2164                 else
2165                     p = strchr (p, '\0');
2166             }
2167         }
2168         else if (strncmp (p, "filename=", sizeof ("filename=") - 1) == 0)
2169         {
2170             p += sizeof ("filename=") - 1;
2171             const char *c = strchr (p, ';');
2172             if (c == NULL)
2173             {
2174                 c = strchr (p, '\0');
2175                 continue;
2176             }
2177             char *fn = (char *) alloca (c - p + 1);
2178             strlcpy (fn, p, c - p);
2179             fn[c - p] = '\0';
2180 
2181             // A file name of "asl" is special and is another way to indicate
2182             // that logging should be done via ASL, not by file.
2183             if (strcmp (fn, "asl") == 0)
2184             {
2185                 DNBLogToASL ();
2186             }
2187             else
2188             {
2189                 FILE *f = fopen (fn, "w");
2190                 if (f)
2191                 {
2192                     DNBLogSetLogFile (f);
2193                     DNBEnableLogging (f, DNBLogGetLogMask ());
2194                     DNBLogToFile ();
2195                 }
2196             }
2197             p = c + 1;
2198         }
2199 #endif /* #if 0 to enforce ASL logging only.  */
2200     else {
2201       // Ignore unknown argument
2202       const char *c = strchr(p, ';');
2203       if (c)
2204         p = c + 1;
2205       else
2206         p = strchr(p, '\0');
2207     }
2208   }
2209 
2210   return rnb_success;
2211 }
2212 
2213 rnb_err_t RNBRemote::HandlePacket_QThreadSuffixSupported(const char *p) {
2214   m_thread_suffix_supported = true;
2215   return SendPacket("OK");
2216 }
2217 
2218 rnb_err_t RNBRemote::HandlePacket_QStartNoAckMode(const char *p) {
2219   // Send the OK packet first so the correct checksum is appended...
2220   rnb_err_t result = SendPacket("OK");
2221   m_noack_mode = true;
2222   return result;
2223 }
2224 
2225 rnb_err_t RNBRemote::HandlePacket_QSetLogging(const char *p) {
2226   p += sizeof("QSetLogging:") - 1;
2227   rnb_err_t result = set_logging(p);
2228   if (result == rnb_success)
2229     return SendPacket("OK");
2230   else
2231     return SendPacket("E35");
2232 }
2233 
2234 rnb_err_t RNBRemote::HandlePacket_QSetDisableASLR(const char *p) {
2235   extern int g_disable_aslr;
2236   p += sizeof("QSetDisableASLR:") - 1;
2237   switch (*p) {
2238   case '0':
2239     g_disable_aslr = 0;
2240     break;
2241   case '1':
2242     g_disable_aslr = 1;
2243     break;
2244   default:
2245     return SendPacket("E56");
2246   }
2247   return SendPacket("OK");
2248 }
2249 
2250 rnb_err_t RNBRemote::HandlePacket_QSetSTDIO(const char *p) {
2251   // Only set stdin/out/err if we don't already have a process
2252   if (!m_ctx.HasValidProcessID()) {
2253     bool success = false;
2254     // Check the seventh character since the packet will be one of:
2255     // QSetSTDIN
2256     // QSetSTDOUT
2257     // QSetSTDERR
2258     StdStringExtractor packet(p);
2259     packet.SetFilePos(7);
2260     char ch = packet.GetChar();
2261     while (packet.GetChar() != ':')
2262       /* Do nothing. */;
2263 
2264     switch (ch) {
2265     case 'I': // STDIN
2266       packet.GetHexByteString(m_ctx.GetSTDIN());
2267       success = !m_ctx.GetSTDIN().empty();
2268       break;
2269 
2270     case 'O': // STDOUT
2271       packet.GetHexByteString(m_ctx.GetSTDOUT());
2272       success = !m_ctx.GetSTDOUT().empty();
2273       break;
2274 
2275     case 'E': // STDERR
2276       packet.GetHexByteString(m_ctx.GetSTDERR());
2277       success = !m_ctx.GetSTDERR().empty();
2278       break;
2279 
2280     default:
2281       break;
2282     }
2283     if (success)
2284       return SendPacket("OK");
2285     return SendPacket("E57");
2286   }
2287   return SendPacket("E58");
2288 }
2289 
2290 rnb_err_t RNBRemote::HandlePacket_QSetWorkingDir(const char *p) {
2291   // Only set the working directory if we don't already have a process
2292   if (!m_ctx.HasValidProcessID()) {
2293     StdStringExtractor packet(p += sizeof("QSetWorkingDir:") - 1);
2294     if (packet.GetHexByteString(m_ctx.GetWorkingDir())) {
2295       struct stat working_dir_stat;
2296       if (::stat(m_ctx.GetWorkingDirPath(), &working_dir_stat) == -1) {
2297         m_ctx.GetWorkingDir().clear();
2298         return SendPacket("E61"); // Working directory doesn't exist...
2299       } else if ((working_dir_stat.st_mode & S_IFMT) == S_IFDIR) {
2300         return SendPacket("OK");
2301       } else {
2302         m_ctx.GetWorkingDir().clear();
2303         return SendPacket("E62"); // Working directory isn't a directory...
2304       }
2305     }
2306     return SendPacket("E59"); // Invalid path
2307   }
2308   return SendPacket(
2309       "E60"); // Already had a process, too late to set working dir
2310 }
2311 
2312 rnb_err_t RNBRemote::HandlePacket_QSyncThreadState(const char *p) {
2313   if (!m_ctx.HasValidProcessID()) {
2314     // We allow gdb to connect to a server that hasn't started running
2315     // the target yet.  gdb still wants to ask questions about it and
2316     // freaks out if it gets an error.  So just return OK here.
2317     return SendPacket("OK");
2318   }
2319 
2320   errno = 0;
2321   p += strlen("QSyncThreadState:");
2322   nub_thread_t tid = strtoul(p, NULL, 16);
2323   if (errno != 0 && tid == 0) {
2324     return HandlePacket_ILLFORMED(
2325         __FILE__, __LINE__, p,
2326         "Invalid thread number in QSyncThreadState packet");
2327   }
2328   if (DNBProcessSyncThreadState(m_ctx.ProcessID(), tid))
2329     return SendPacket("OK");
2330   else
2331     return SendPacket("E61");
2332 }
2333 
2334 rnb_err_t RNBRemote::HandlePacket_QSetDetachOnError(const char *p) {
2335   p += sizeof("QSetDetachOnError:") - 1;
2336   bool should_detach = true;
2337   switch (*p) {
2338   case '0':
2339     should_detach = false;
2340     break;
2341   case '1':
2342     should_detach = true;
2343     break;
2344   default:
2345     return HandlePacket_ILLFORMED(
2346         __FILE__, __LINE__, p,
2347         "Invalid value for QSetDetachOnError - should be 0 or 1");
2348     break;
2349   }
2350 
2351   m_ctx.SetDetachOnError(should_detach);
2352   return SendPacket("OK");
2353 }
2354 
2355 rnb_err_t RNBRemote::HandlePacket_QListThreadsInStopReply(const char *p) {
2356   // If this packet is received, it allows us to send an extra key/value
2357   // pair in the stop reply packets where we will list all of the thread IDs
2358   // separated by commas:
2359   //
2360   //  "threads:10a,10b,10c;"
2361   //
2362   // This will get included in the stop reply packet as something like:
2363   //
2364   //  "T11thread:10a;00:00000000;01:00010203:threads:10a,10b,10c;"
2365   //
2366   // This can save two packets on each stop: qfThreadInfo/qsThreadInfo and
2367   // speed things up a bit.
2368   //
2369   // Send the OK packet first so the correct checksum is appended...
2370   rnb_err_t result = SendPacket("OK");
2371   m_list_threads_in_stop_reply = true;
2372 
2373   return result;
2374 }
2375 
2376 rnb_err_t RNBRemote::HandlePacket_QSetMaxPayloadSize(const char *p) {
2377   /* The number of characters in a packet payload that gdb is
2378    prepared to accept.  The packet-start char, packet-end char,
2379    2 checksum chars and terminating null character are not included
2380    in this size.  */
2381   p += sizeof("QSetMaxPayloadSize:") - 1;
2382   errno = 0;
2383   uint32_t size = static_cast<uint32_t>(strtoul(p, NULL, 16));
2384   if (errno != 0 && size == 0) {
2385     return HandlePacket_ILLFORMED(
2386         __FILE__, __LINE__, p, "Invalid length in QSetMaxPayloadSize packet");
2387   }
2388   m_max_payload_size = size;
2389   return SendPacket("OK");
2390 }
2391 
2392 rnb_err_t RNBRemote::HandlePacket_QSetMaxPacketSize(const char *p) {
2393   /* This tells us the largest packet that gdb can handle.
2394    i.e. the size of gdb's packet-reading buffer.
2395    QSetMaxPayloadSize is preferred because it is less ambiguous.  */
2396   p += sizeof("QSetMaxPacketSize:") - 1;
2397   errno = 0;
2398   uint32_t size = static_cast<uint32_t>(strtoul(p, NULL, 16));
2399   if (errno != 0 && size == 0) {
2400     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
2401                                   "Invalid length in QSetMaxPacketSize packet");
2402   }
2403   m_max_payload_size = size - 5;
2404   return SendPacket("OK");
2405 }
2406 
2407 rnb_err_t RNBRemote::HandlePacket_QEnvironment(const char *p) {
2408   /* This sets the environment for the target program.  The packet is of the
2409    form:
2410 
2411    QEnvironment:VARIABLE=VALUE
2412 
2413    */
2414 
2415   DNBLogThreadedIf(
2416       LOG_RNB_REMOTE, "%8u RNBRemote::%s Handling QEnvironment: \"%s\"",
2417       (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__, p);
2418 
2419   p += sizeof("QEnvironment:") - 1;
2420   RNBContext &ctx = Context();
2421 
2422   ctx.PushEnvironment(p);
2423   return SendPacket("OK");
2424 }
2425 
2426 rnb_err_t RNBRemote::HandlePacket_QEnvironmentHexEncoded(const char *p) {
2427   /* This sets the environment for the target program.  The packet is of the
2428      form:
2429 
2430       QEnvironmentHexEncoded:VARIABLE=VALUE
2431 
2432       The VARIABLE=VALUE part is sent hex-encoded so characters like '#' with
2433      special
2434       meaning in the remote protocol won't break it.
2435   */
2436 
2437   DNBLogThreadedIf(LOG_RNB_REMOTE,
2438                    "%8u RNBRemote::%s Handling QEnvironmentHexEncoded: \"%s\"",
2439                    (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true),
2440                    __FUNCTION__, p);
2441 
2442   p += sizeof("QEnvironmentHexEncoded:") - 1;
2443 
2444   std::string arg;
2445   const char *c;
2446   c = p;
2447   while (*c != '\0') {
2448     if (*(c + 1) == '\0') {
2449       return HandlePacket_ILLFORMED(
2450           __FILE__, __LINE__, p,
2451           "non-hex char in arg on 'QEnvironmentHexEncoded' pkt");
2452     }
2453     char smallbuf[3];
2454     smallbuf[0] = *c;
2455     smallbuf[1] = *(c + 1);
2456     smallbuf[2] = '\0';
2457     errno = 0;
2458     int ch = static_cast<int>(strtoul(smallbuf, NULL, 16));
2459     if (errno != 0 && ch == 0) {
2460       return HandlePacket_ILLFORMED(
2461           __FILE__, __LINE__, p,
2462           "non-hex char in arg on 'QEnvironmentHexEncoded' pkt");
2463     }
2464     arg.push_back(ch);
2465     c += 2;
2466   }
2467 
2468   RNBContext &ctx = Context();
2469   if (arg.length() > 0)
2470     ctx.PushEnvironment(arg.c_str());
2471 
2472   return SendPacket("OK");
2473 }
2474 
2475 rnb_err_t RNBRemote::HandlePacket_QLaunchArch(const char *p) {
2476   p += sizeof("QLaunchArch:") - 1;
2477   if (DNBSetArchitecture(p))
2478     return SendPacket("OK");
2479   return SendPacket("E63");
2480 }
2481 
2482 rnb_err_t RNBRemote::HandlePacket_QSetProcessEvent(const char *p) {
2483   p += sizeof("QSetProcessEvent:") - 1;
2484   // If the process is running, then send the event to the process, otherwise
2485   // store it in the context.
2486   if (Context().HasValidProcessID()) {
2487     if (DNBProcessSendEvent(Context().ProcessID(), p))
2488       return SendPacket("OK");
2489     else
2490       return SendPacket("E80");
2491   } else {
2492     Context().PushProcessEvent(p);
2493   }
2494   return SendPacket("OK");
2495 }
2496 
2497 void append_hex_value(std::ostream &ostrm, const void *buf, size_t buf_size,
2498                       bool swap) {
2499   int i;
2500   const uint8_t *p = (const uint8_t *)buf;
2501   if (swap) {
2502     for (i = static_cast<int>(buf_size) - 1; i >= 0; i--)
2503       ostrm << RAWHEX8(p[i]);
2504   } else {
2505     for (size_t i = 0; i < buf_size; i++)
2506       ostrm << RAWHEX8(p[i]);
2507   }
2508 }
2509 
2510 std::string cstring_to_asciihex_string(const char *str) {
2511   std::string hex_str;
2512   hex_str.reserve (strlen (str) * 2);
2513   while (str && *str) {
2514     uint8_t c = *str++;
2515     char hexbuf[5];
2516     snprintf (hexbuf, sizeof(hexbuf), "%02x", c);
2517     hex_str += hexbuf;
2518   }
2519   return hex_str;
2520 }
2521 
2522 void append_hexified_string(std::ostream &ostrm, const std::string &string) {
2523   size_t string_size = string.size();
2524   const char *string_buf = string.c_str();
2525   for (size_t i = 0; i < string_size; i++) {
2526     ostrm << RAWHEX8(*(string_buf + i));
2527   }
2528 }
2529 
2530 void register_value_in_hex_fixed_width(std::ostream &ostrm, nub_process_t pid,
2531                                        nub_thread_t tid,
2532                                        const register_map_entry_t *reg,
2533                                        const DNBRegisterValue *reg_value_ptr) {
2534   if (reg != NULL) {
2535     DNBRegisterValue reg_value;
2536     if (reg_value_ptr == NULL) {
2537       if (DNBThreadGetRegisterValueByID(pid, tid, reg->nub_info.set,
2538                                         reg->nub_info.reg, &reg_value))
2539         reg_value_ptr = &reg_value;
2540     }
2541 
2542     if (reg_value_ptr) {
2543       append_hex_value(ostrm, reg_value_ptr->value.v_uint8, reg->nub_info.size,
2544                        false);
2545     } else {
2546       // If we fail to read a register value, check if it has a default
2547       // fail value. If it does, return this instead in case some of
2548       // the registers are not available on the current system.
2549       if (reg->nub_info.size > 0) {
2550         std::basic_string<uint8_t> zeros(reg->nub_info.size, '\0');
2551         append_hex_value(ostrm, zeros.data(), zeros.size(), false);
2552       }
2553     }
2554   }
2555 }
2556 
2557 void debugserver_regnum_with_fixed_width_hex_register_value(
2558     std::ostream &ostrm, nub_process_t pid, nub_thread_t tid,
2559     const register_map_entry_t *reg, const DNBRegisterValue *reg_value_ptr) {
2560   // Output the register number as 'NN:VVVVVVVV;' where NN is a 2 bytes HEX
2561   // gdb register number, and VVVVVVVV is the correct number of hex bytes
2562   // as ASCII for the register value.
2563   if (reg != NULL) {
2564     ostrm << RAWHEX8(reg->debugserver_regnum) << ':';
2565     register_value_in_hex_fixed_width(ostrm, pid, tid, reg, reg_value_ptr);
2566     ostrm << ';';
2567   }
2568 }
2569 
2570 void RNBRemote::DispatchQueueOffsets::GetThreadQueueInfo(
2571     nub_process_t pid, nub_addr_t dispatch_qaddr, nub_addr_t &dispatch_queue_t,
2572     std::string &queue_name, uint64_t &queue_width,
2573     uint64_t &queue_serialnum) const {
2574   queue_name.clear();
2575   queue_width = 0;
2576   queue_serialnum = 0;
2577 
2578   if (IsValid() && dispatch_qaddr != INVALID_NUB_ADDRESS &&
2579       dispatch_qaddr != 0) {
2580     dispatch_queue_t = DNBProcessMemoryReadPointer(pid, dispatch_qaddr);
2581     if (dispatch_queue_t) {
2582       queue_width = DNBProcessMemoryReadInteger(
2583           pid, dispatch_queue_t + dqo_width, dqo_width_size, 0);
2584       queue_serialnum = DNBProcessMemoryReadInteger(
2585           pid, dispatch_queue_t + dqo_serialnum, dqo_serialnum_size, 0);
2586 
2587       if (dqo_version >= 4) {
2588         // libdispatch versions 4+, pointer to dispatch name is in the
2589         // queue structure.
2590         nub_addr_t pointer_to_label_address = dispatch_queue_t + dqo_label;
2591         nub_addr_t label_addr =
2592             DNBProcessMemoryReadPointer(pid, pointer_to_label_address);
2593         if (label_addr)
2594           queue_name = DNBProcessMemoryReadCString(pid, label_addr);
2595       } else {
2596         // libdispatch versions 1-3, dispatch name is a fixed width char array
2597         // in the queue structure.
2598         queue_name = DNBProcessMemoryReadCStringFixed(
2599             pid, dispatch_queue_t + dqo_label, dqo_label_size);
2600       }
2601     }
2602   }
2603 }
2604 
2605 struct StackMemory {
2606   uint8_t bytes[2 * sizeof(nub_addr_t)];
2607   nub_size_t length;
2608 };
2609 typedef std::map<nub_addr_t, StackMemory> StackMemoryMap;
2610 
2611 static void ReadStackMemory(nub_process_t pid, nub_thread_t tid,
2612                             StackMemoryMap &stack_mmap,
2613                             uint32_t backtrace_limit = 256) {
2614   DNBRegisterValue reg_value;
2615   if (DNBThreadGetRegisterValueByID(pid, tid, REGISTER_SET_GENERIC,
2616                                     GENERIC_REGNUM_FP, &reg_value)) {
2617     uint32_t frame_count = 0;
2618     uint64_t fp = 0;
2619     if (reg_value.info.size == 4)
2620       fp = reg_value.value.uint32;
2621     else
2622       fp = reg_value.value.uint64;
2623     while (fp != 0) {
2624       // Make sure we never recurse more than 256 times so we don't recurse too
2625       // far or
2626       // store up too much memory in the expedited cache
2627       if (++frame_count > backtrace_limit)
2628         break;
2629 
2630       const nub_size_t read_size = reg_value.info.size * 2;
2631       StackMemory stack_memory;
2632       stack_memory.length = read_size;
2633       if (DNBProcessMemoryRead(pid, fp, read_size, stack_memory.bytes) !=
2634           read_size)
2635         break;
2636       // Make sure we don't try to put the same stack memory in more than once
2637       if (stack_mmap.find(fp) != stack_mmap.end())
2638         break;
2639       // Put the entry into the cache
2640       stack_mmap[fp] = stack_memory;
2641       // Dereference the frame pointer to get to the previous frame pointer
2642       if (reg_value.info.size == 4)
2643         fp = ((uint32_t *)stack_memory.bytes)[0];
2644       else
2645         fp = ((uint64_t *)stack_memory.bytes)[0];
2646     }
2647   }
2648 }
2649 
2650 rnb_err_t RNBRemote::SendStopReplyPacketForThread(nub_thread_t tid) {
2651   const nub_process_t pid = m_ctx.ProcessID();
2652   if (pid == INVALID_NUB_PROCESS)
2653     return SendPacket("E50");
2654 
2655   struct DNBThreadStopInfo tid_stop_info;
2656 
2657   /* Fill the remaining space in this packet with as many registers
2658    as we can stuff in there.  */
2659 
2660   if (DNBThreadGetStopReason(pid, tid, &tid_stop_info)) {
2661     const bool did_exec = tid_stop_info.reason == eStopTypeExec;
2662     if (did_exec) {
2663       RNBRemote::InitializeRegisters(true);
2664 
2665       // Reset any symbols that need resetting when we exec
2666       m_dispatch_queue_offsets_addr = INVALID_NUB_ADDRESS;
2667       m_dispatch_queue_offsets.Clear();
2668     }
2669 
2670     std::ostringstream ostrm;
2671     // Output the T packet with the thread
2672     ostrm << 'T';
2673     int signum = tid_stop_info.details.signal.signo;
2674     DNBLogThreadedIf(
2675         LOG_RNB_PROC, "%8d %s got signal signo = %u, exc_type = %u",
2676         (uint32_t)m_comm.Timer().ElapsedMicroSeconds(true), __FUNCTION__,
2677         signum, tid_stop_info.details.exception.type);
2678 
2679     // Translate any mach exceptions to gdb versions, unless they are
2680     // common exceptions like a breakpoint or a soft signal.
2681     switch (tid_stop_info.details.exception.type) {
2682     default:
2683       signum = 0;
2684       break;
2685     case EXC_BREAKPOINT:
2686       signum = SIGTRAP;
2687       break;
2688     case EXC_BAD_ACCESS:
2689       signum = TARGET_EXC_BAD_ACCESS;
2690       break;
2691     case EXC_BAD_INSTRUCTION:
2692       signum = TARGET_EXC_BAD_INSTRUCTION;
2693       break;
2694     case EXC_ARITHMETIC:
2695       signum = TARGET_EXC_ARITHMETIC;
2696       break;
2697     case EXC_EMULATION:
2698       signum = TARGET_EXC_EMULATION;
2699       break;
2700     case EXC_SOFTWARE:
2701       if (tid_stop_info.details.exception.data_count == 2 &&
2702           tid_stop_info.details.exception.data[0] == EXC_SOFT_SIGNAL)
2703         signum = static_cast<int>(tid_stop_info.details.exception.data[1]);
2704       else
2705         signum = TARGET_EXC_SOFTWARE;
2706       break;
2707     }
2708 
2709     ostrm << RAWHEX8(signum & 0xff);
2710 
2711     ostrm << std::hex << "thread:" << tid << ';';
2712 
2713     const char *thread_name = DNBThreadGetName(pid, tid);
2714     if (thread_name && thread_name[0]) {
2715       size_t thread_name_len = strlen(thread_name);
2716 
2717       if (::strcspn(thread_name, "$#+-;:") == thread_name_len)
2718         ostrm << std::hex << "name:" << thread_name << ';';
2719       else {
2720         // the thread name contains special chars, send as hex bytes
2721         ostrm << std::hex << "hexname:";
2722         const uint8_t *u_thread_name = (const uint8_t *)thread_name;
2723         for (size_t i = 0; i < thread_name_len; i++)
2724           ostrm << RAWHEX8(u_thread_name[i]);
2725         ostrm << ';';
2726       }
2727     }
2728 
2729     // If a 'QListThreadsInStopReply' was sent to enable this feature, we
2730     // will send all thread IDs back in the "threads" key whose value is
2731     // a list of hex thread IDs separated by commas:
2732     //  "threads:10a,10b,10c;"
2733     // This will save the debugger from having to send a pair of qfThreadInfo
2734     // and qsThreadInfo packets, but it also might take a lot of room in the
2735     // stop reply packet, so it must be enabled only on systems where there
2736     // are no limits on packet lengths.
2737     if (m_list_threads_in_stop_reply) {
2738       const nub_size_t numthreads = DNBProcessGetNumThreads(pid);
2739       if (numthreads > 0) {
2740         std::vector<uint64_t> pc_values;
2741         ostrm << std::hex << "threads:";
2742         for (nub_size_t i = 0; i < numthreads; ++i) {
2743           nub_thread_t th = DNBProcessGetThreadAtIndex(pid, i);
2744           if (i > 0)
2745             ostrm << ',';
2746           ostrm << std::hex << th;
2747           DNBRegisterValue pc_regval;
2748           if (DNBThreadGetRegisterValueByID(pid, th, REGISTER_SET_GENERIC,
2749                                             GENERIC_REGNUM_PC, &pc_regval)) {
2750             uint64_t pc = INVALID_NUB_ADDRESS;
2751             if (pc_regval.value.uint64 != INVALID_NUB_ADDRESS) {
2752               if (pc_regval.info.size == 4) {
2753                 pc = pc_regval.value.uint32;
2754               } else if (pc_regval.info.size == 8) {
2755                 pc = pc_regval.value.uint64;
2756               }
2757               if (pc != INVALID_NUB_ADDRESS) {
2758                 pc_values.push_back(pc);
2759               }
2760             }
2761           }
2762         }
2763         ostrm << ';';
2764 
2765         // If we failed to get any of the thread pc values, the size of our
2766         // vector will not
2767         // be the same as the # of threads.  Don't provide any expedited thread
2768         // pc values in
2769         // that case.  This should not happen.
2770         if (pc_values.size() == numthreads) {
2771           ostrm << std::hex << "thread-pcs:";
2772           for (nub_size_t i = 0; i < numthreads; ++i) {
2773             if (i > 0)
2774               ostrm << ',';
2775             ostrm << std::hex << pc_values[i];
2776           }
2777           ostrm << ';';
2778         }
2779       }
2780 
2781       // Include JSON info that describes the stop reason for any threads
2782       // that actually have stop reasons. We use the new "jstopinfo" key
2783       // whose values is hex ascii JSON that contains the thread IDs
2784       // thread stop info only for threads that have stop reasons. Only send
2785       // this if we have more than one thread otherwise this packet has all
2786       // the info it needs.
2787       if (numthreads > 1) {
2788         const bool threads_with_valid_stop_info_only = true;
2789         JSONGenerator::ObjectSP threads_info_sp =
2790             GetJSONThreadsInfo(threads_with_valid_stop_info_only);
2791         if (threads_info_sp) {
2792           ostrm << std::hex << "jstopinfo:";
2793           std::ostringstream json_strm;
2794           threads_info_sp->Dump(json_strm);
2795           append_hexified_string(ostrm, json_strm.str());
2796           ostrm << ';';
2797         }
2798       }
2799     }
2800 
2801     if (g_num_reg_entries == 0)
2802       InitializeRegisters();
2803 
2804     if (g_reg_entries != NULL) {
2805       DNBRegisterValue reg_value;
2806       for (uint32_t reg = 0; reg < g_num_reg_entries; reg++) {
2807         // Expedite all registers in the first register set that aren't
2808         // contained in other registers
2809         if (g_reg_entries[reg].nub_info.set == 1 &&
2810             g_reg_entries[reg].nub_info.value_regs == NULL) {
2811           if (!DNBThreadGetRegisterValueByID(
2812                   pid, tid, g_reg_entries[reg].nub_info.set,
2813                   g_reg_entries[reg].nub_info.reg, &reg_value))
2814             continue;
2815 
2816           debugserver_regnum_with_fixed_width_hex_register_value(
2817               ostrm, pid, tid, &g_reg_entries[reg], &reg_value);
2818         }
2819       }
2820     }
2821 
2822     if (did_exec) {
2823       ostrm << "reason:exec;";
2824     } else if (tid_stop_info.details.exception.type) {
2825       ostrm << "metype:" << std::hex << tid_stop_info.details.exception.type
2826             << ';';
2827       ostrm << "mecount:" << std::hex
2828             << tid_stop_info.details.exception.data_count << ';';
2829       for (nub_size_t i = 0; i < tid_stop_info.details.exception.data_count;
2830            ++i)
2831         ostrm << "medata:" << std::hex
2832               << tid_stop_info.details.exception.data[i] << ';';
2833     }
2834 
2835     // Add expedited stack memory so stack backtracing doesn't need to read
2836     // anything from the
2837     // frame pointer chain.
2838     StackMemoryMap stack_mmap;
2839     ReadStackMemory(pid, tid, stack_mmap, 2);
2840     if (!stack_mmap.empty()) {
2841       for (const auto &stack_memory : stack_mmap) {
2842         ostrm << "memory:" << HEXBASE << stack_memory.first << '=';
2843         append_hex_value(ostrm, stack_memory.second.bytes,
2844                          stack_memory.second.length, false);
2845         ostrm << ';';
2846       }
2847     }
2848 
2849     return SendPacket(ostrm.str());
2850   }
2851   return SendPacket("E51");
2852 }
2853 
2854 /* '?'
2855  The stop reply packet - tell gdb what the status of the inferior is.
2856  Often called the questionmark_packet.  */
2857 
2858 rnb_err_t RNBRemote::HandlePacket_last_signal(const char *unused) {
2859   if (!m_ctx.HasValidProcessID()) {
2860     // Inferior is not yet specified/running
2861     return SendPacket("E02");
2862   }
2863 
2864   nub_process_t pid = m_ctx.ProcessID();
2865   nub_state_t pid_state = DNBProcessGetState(pid);
2866 
2867   switch (pid_state) {
2868   case eStateAttaching:
2869   case eStateLaunching:
2870   case eStateRunning:
2871   case eStateStepping:
2872   case eStateDetached:
2873     return rnb_success; // Ignore
2874 
2875   case eStateSuspended:
2876   case eStateStopped:
2877   case eStateCrashed: {
2878     nub_thread_t tid = DNBProcessGetCurrentThread(pid);
2879     // Make sure we set the current thread so g and p packets return
2880     // the data the gdb will expect.
2881     SetCurrentThread(tid);
2882 
2883     SendStopReplyPacketForThread(tid);
2884   } break;
2885 
2886   case eStateInvalid:
2887   case eStateUnloaded:
2888   case eStateExited: {
2889     char pid_exited_packet[16] = "";
2890     int pid_status = 0;
2891     // Process exited with exit status
2892     if (!DNBProcessGetExitStatus(pid, &pid_status))
2893       pid_status = 0;
2894 
2895     if (pid_status) {
2896       if (WIFEXITED(pid_status))
2897         snprintf(pid_exited_packet, sizeof(pid_exited_packet), "W%02x",
2898                  WEXITSTATUS(pid_status));
2899       else if (WIFSIGNALED(pid_status))
2900         snprintf(pid_exited_packet, sizeof(pid_exited_packet), "X%02x",
2901                  WTERMSIG(pid_status));
2902       else if (WIFSTOPPED(pid_status))
2903         snprintf(pid_exited_packet, sizeof(pid_exited_packet), "S%02x",
2904                  WSTOPSIG(pid_status));
2905     }
2906 
2907     // If we have an empty exit packet, lets fill one in to be safe.
2908     if (!pid_exited_packet[0]) {
2909       strlcpy(pid_exited_packet, "W00", sizeof(pid_exited_packet) - 1);
2910       pid_exited_packet[sizeof(pid_exited_packet) - 1] = '\0';
2911     }
2912 
2913     const char *exit_info = DNBProcessGetExitInfo(pid);
2914     if (exit_info != NULL && *exit_info != '\0') {
2915       std::ostringstream exit_packet;
2916       exit_packet << pid_exited_packet;
2917       exit_packet << ';';
2918       exit_packet << RAW_HEXBASE << "description";
2919       exit_packet << ':';
2920       for (size_t i = 0; exit_info[i] != '\0'; i++)
2921         exit_packet << RAWHEX8(exit_info[i]);
2922       exit_packet << ';';
2923       return SendPacket(exit_packet.str());
2924     } else
2925       return SendPacket(pid_exited_packet);
2926   } break;
2927   }
2928   return rnb_success;
2929 }
2930 
2931 rnb_err_t RNBRemote::HandlePacket_M(const char *p) {
2932   if (p == NULL || p[0] == '\0' || strlen(p) < 3) {
2933     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p, "Too short M packet");
2934   }
2935 
2936   char *c;
2937   p++;
2938   errno = 0;
2939   nub_addr_t addr = strtoull(p, &c, 16);
2940   if (errno != 0 && addr == 0) {
2941     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
2942                                   "Invalid address in M packet");
2943   }
2944   if (*c != ',') {
2945     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
2946                                   "Comma sep missing in M packet");
2947   }
2948 
2949   /* Advance 'p' to the length part of the packet.  */
2950   p += (c - p) + 1;
2951 
2952   errno = 0;
2953   unsigned long length = strtoul(p, &c, 16);
2954   if (errno != 0 && length == 0) {
2955     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
2956                                   "Invalid length in M packet");
2957   }
2958   if (length == 0) {
2959     return SendPacket("OK");
2960   }
2961 
2962   if (*c != ':') {
2963     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
2964                                   "Missing colon in M packet");
2965   }
2966   /* Advance 'p' to the data part of the packet.  */
2967   p += (c - p) + 1;
2968 
2969   size_t datalen = strlen(p);
2970   if (datalen & 0x1) {
2971     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
2972                                   "Uneven # of hex chars for data in M packet");
2973   }
2974   if (datalen == 0) {
2975     return SendPacket("OK");
2976   }
2977 
2978   uint8_t *buf = (uint8_t *)alloca(datalen / 2);
2979   uint8_t *i = buf;
2980 
2981   while (*p != '\0' && *(p + 1) != '\0') {
2982     char hexbuf[3];
2983     hexbuf[0] = *p;
2984     hexbuf[1] = *(p + 1);
2985     hexbuf[2] = '\0';
2986     errno = 0;
2987     uint8_t byte = strtoul(hexbuf, NULL, 16);
2988     if (errno != 0 && byte == 0) {
2989       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
2990                                     "Invalid hex byte in M packet");
2991     }
2992     *i++ = byte;
2993     p += 2;
2994   }
2995 
2996   nub_size_t wrote =
2997       DNBProcessMemoryWrite(m_ctx.ProcessID(), addr, length, buf);
2998   if (wrote != length)
2999     return SendPacket("E09");
3000   else
3001     return SendPacket("OK");
3002 }
3003 
3004 rnb_err_t RNBRemote::HandlePacket_m(const char *p) {
3005   if (p == NULL || p[0] == '\0' || strlen(p) < 3) {
3006     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p, "Too short m packet");
3007   }
3008 
3009   char *c;
3010   p++;
3011   errno = 0;
3012   nub_addr_t addr = strtoull(p, &c, 16);
3013   if (errno != 0 && addr == 0) {
3014     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3015                                   "Invalid address in m packet");
3016   }
3017   if (*c != ',') {
3018     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3019                                   "Comma sep missing in m packet");
3020   }
3021 
3022   /* Advance 'p' to the length part of the packet.  */
3023   p += (c - p) + 1;
3024 
3025   errno = 0;
3026   auto length = strtoul(p, NULL, 16);
3027   if (errno != 0 && length == 0) {
3028     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3029                                   "Invalid length in m packet");
3030   }
3031   if (length == 0) {
3032     return SendPacket("");
3033   }
3034 
3035   std::string buf(length, '\0');
3036   if (buf.empty()) {
3037     return SendPacket("E78");
3038   }
3039   nub_size_t bytes_read =
3040       DNBProcessMemoryRead(m_ctx.ProcessID(), addr, buf.size(), &buf[0]);
3041   if (bytes_read == 0) {
3042     return SendPacket("E08");
3043   }
3044 
3045   // "The reply may contain fewer bytes than requested if the server was able
3046   //  to read only part of the region of memory."
3047   length = bytes_read;
3048 
3049   std::ostringstream ostrm;
3050   for (unsigned long i = 0; i < length; i++)
3051     ostrm << RAWHEX8(buf[i]);
3052   return SendPacket(ostrm.str());
3053 }
3054 
3055 // Read memory, sent it up as binary data.
3056 // Usage:  xADDR,LEN
3057 // ADDR and LEN are both base 16.
3058 
3059 // Responds with 'OK' for zero-length request
3060 // or
3061 //
3062 // DATA
3063 //
3064 // where DATA is the binary data payload.
3065 
3066 rnb_err_t RNBRemote::HandlePacket_x(const char *p) {
3067   if (p == NULL || p[0] == '\0' || strlen(p) < 3) {
3068     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p, "Too short X packet");
3069   }
3070 
3071   char *c;
3072   p++;
3073   errno = 0;
3074   nub_addr_t addr = strtoull(p, &c, 16);
3075   if (errno != 0) {
3076     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3077                                   "Invalid address in X packet");
3078   }
3079   if (*c != ',') {
3080     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3081                                   "Comma sep missing in X packet");
3082   }
3083 
3084   /* Advance 'p' to the number of bytes to be read.  */
3085   p += (c - p) + 1;
3086 
3087   errno = 0;
3088   auto length = strtoul(p, NULL, 16);
3089   if (errno != 0) {
3090     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3091                                   "Invalid length in x packet");
3092   }
3093 
3094   // zero length read means this is a test of whether that packet is implemented
3095   // or not.
3096   if (length == 0) {
3097     return SendPacket("OK");
3098   }
3099 
3100   std::vector<uint8_t> buf(length);
3101 
3102   if (buf.capacity() != length) {
3103     return SendPacket("E79");
3104   }
3105   nub_size_t bytes_read =
3106       DNBProcessMemoryRead(m_ctx.ProcessID(), addr, buf.size(), &buf[0]);
3107   if (bytes_read == 0) {
3108     return SendPacket("E80");
3109   }
3110 
3111   std::vector<uint8_t> buf_quoted;
3112   buf_quoted.reserve(bytes_read + 30);
3113   for (nub_size_t i = 0; i < bytes_read; i++) {
3114     if (buf[i] == '#' || buf[i] == '$' || buf[i] == '}' || buf[i] == '*') {
3115       buf_quoted.push_back(0x7d);
3116       buf_quoted.push_back(buf[i] ^ 0x20);
3117     } else {
3118       buf_quoted.push_back(buf[i]);
3119     }
3120   }
3121   length = buf_quoted.size();
3122 
3123   std::ostringstream ostrm;
3124   for (unsigned long i = 0; i < length; i++)
3125     ostrm << buf_quoted[i];
3126 
3127   return SendPacket(ostrm.str());
3128 }
3129 
3130 rnb_err_t RNBRemote::HandlePacket_X(const char *p) {
3131   if (p == NULL || p[0] == '\0' || strlen(p) < 3) {
3132     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p, "Too short X packet");
3133   }
3134 
3135   char *c;
3136   p++;
3137   errno = 0;
3138   nub_addr_t addr = strtoull(p, &c, 16);
3139   if (errno != 0 && addr == 0) {
3140     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3141                                   "Invalid address in X packet");
3142   }
3143   if (*c != ',') {
3144     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3145                                   "Comma sep missing in X packet");
3146   }
3147 
3148   /* Advance 'p' to the length part of the packet.  NB this is the length of the
3149      packet
3150      including any escaped chars.  The data payload may be a little bit smaller
3151      after
3152      decoding.  */
3153   p += (c - p) + 1;
3154 
3155   errno = 0;
3156   auto length = strtoul(p, NULL, 16);
3157   if (errno != 0 && length == 0) {
3158     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3159                                   "Invalid length in X packet");
3160   }
3161 
3162   // I think gdb sends a zero length write request to test whether this
3163   // packet is accepted.
3164   if (length == 0) {
3165     return SendPacket("OK");
3166   }
3167 
3168   std::vector<uint8_t> data = decode_binary_data(c, -1);
3169   std::vector<uint8_t>::const_iterator it;
3170   uint8_t *buf = (uint8_t *)alloca(data.size());
3171   uint8_t *i = buf;
3172   for (it = data.begin(); it != data.end(); ++it) {
3173     *i++ = *it;
3174   }
3175 
3176   nub_size_t wrote =
3177       DNBProcessMemoryWrite(m_ctx.ProcessID(), addr, data.size(), buf);
3178   if (wrote != data.size())
3179     return SendPacket("E08");
3180   return SendPacket("OK");
3181 }
3182 
3183 /* 'g' -- read registers
3184  Get the contents of the registers for the current thread,
3185  send them to gdb.
3186  Should the setting of the Hg packet determine which thread's registers
3187  are returned?  */
3188 
3189 rnb_err_t RNBRemote::HandlePacket_g(const char *p) {
3190   std::ostringstream ostrm;
3191   if (!m_ctx.HasValidProcessID()) {
3192     return SendPacket("E11");
3193   }
3194 
3195   if (g_num_reg_entries == 0)
3196     InitializeRegisters();
3197 
3198   nub_process_t pid = m_ctx.ProcessID();
3199   nub_thread_t tid = ExtractThreadIDFromThreadSuffix(p + 1);
3200   if (tid == INVALID_NUB_THREAD)
3201     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3202                                   "No thread specified in p packet");
3203 
3204   // Get the register context size first by calling with NULL buffer
3205   nub_size_t reg_ctx_size = DNBThreadGetRegisterContext(pid, tid, NULL, 0);
3206   if (reg_ctx_size) {
3207     // Now allocate enough space for the entire register context
3208     std::vector<uint8_t> reg_ctx;
3209     reg_ctx.resize(reg_ctx_size);
3210     // Now read the register context
3211     reg_ctx_size =
3212         DNBThreadGetRegisterContext(pid, tid, &reg_ctx[0], reg_ctx.size());
3213     if (reg_ctx_size) {
3214       append_hex_value(ostrm, reg_ctx.data(), reg_ctx.size(), false);
3215       return SendPacket(ostrm.str());
3216     }
3217   }
3218   return SendPacket("E74");
3219 }
3220 
3221 /* 'G XXX...' -- write registers
3222  How is the thread for these specified, beyond "the current thread"?
3223  Does gdb actually use the Hg packet to set this?  */
3224 
3225 rnb_err_t RNBRemote::HandlePacket_G(const char *p) {
3226   if (!m_ctx.HasValidProcessID()) {
3227     return SendPacket("E11");
3228   }
3229 
3230   if (g_num_reg_entries == 0)
3231     InitializeRegisters();
3232 
3233   StdStringExtractor packet(p);
3234   packet.SetFilePos(1); // Skip the 'G'
3235 
3236   nub_process_t pid = m_ctx.ProcessID();
3237   nub_thread_t tid = ExtractThreadIDFromThreadSuffix(p);
3238   if (tid == INVALID_NUB_THREAD)
3239     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3240                                   "No thread specified in p packet");
3241 
3242   // Get the register context size first by calling with NULL buffer
3243   nub_size_t reg_ctx_size = DNBThreadGetRegisterContext(pid, tid, NULL, 0);
3244   if (reg_ctx_size) {
3245     // Now allocate enough space for the entire register context
3246     std::vector<uint8_t> reg_ctx;
3247     reg_ctx.resize(reg_ctx_size);
3248 
3249     const nub_size_t bytes_extracted =
3250         packet.GetHexBytes(&reg_ctx[0], reg_ctx.size(), 0xcc);
3251     if (bytes_extracted == reg_ctx.size()) {
3252       // Now write the register context
3253       reg_ctx_size =
3254           DNBThreadSetRegisterContext(pid, tid, reg_ctx.data(), reg_ctx.size());
3255       if (reg_ctx_size == reg_ctx.size())
3256         return SendPacket("OK");
3257       else
3258         return SendPacket("E55");
3259     } else {
3260       DNBLogError("RNBRemote::HandlePacket_G(%s): extracted %llu of %llu "
3261                   "bytes, size mismatch\n",
3262                   p, (uint64_t)bytes_extracted, (uint64_t)reg_ctx_size);
3263       return SendPacket("E64");
3264     }
3265   }
3266   return SendPacket("E65");
3267 }
3268 
3269 static bool RNBRemoteShouldCancelCallback(void *not_used) {
3270   RNBRemoteSP remoteSP(g_remoteSP);
3271   if (remoteSP.get() != NULL) {
3272     RNBRemote *remote = remoteSP.get();
3273     return !remote->Comm().IsConnected();
3274   }
3275   return true;
3276 }
3277 
3278 // FORMAT: _MXXXXXX,PPP
3279 //      XXXXXX: big endian hex chars
3280 //      PPP: permissions can be any combo of r w x chars
3281 //
3282 // RESPONSE: XXXXXX
3283 //      XXXXXX: hex address of the newly allocated memory
3284 //      EXX: error code
3285 //
3286 // EXAMPLES:
3287 //      _M123000,rw
3288 //      _M123000,rwx
3289 //      _M123000,xw
3290 
3291 rnb_err_t RNBRemote::HandlePacket_AllocateMemory(const char *p) {
3292   StdStringExtractor packet(p);
3293   packet.SetFilePos(2); // Skip the "_M"
3294 
3295   nub_addr_t size = packet.GetHexMaxU64(StdStringExtractor::BigEndian, 0);
3296   if (size != 0) {
3297     if (packet.GetChar() == ',') {
3298       uint32_t permissions = 0;
3299       char ch;
3300       bool success = true;
3301       while (success && (ch = packet.GetChar()) != '\0') {
3302         switch (ch) {
3303         case 'r':
3304           permissions |= eMemoryPermissionsReadable;
3305           break;
3306         case 'w':
3307           permissions |= eMemoryPermissionsWritable;
3308           break;
3309         case 'x':
3310           permissions |= eMemoryPermissionsExecutable;
3311           break;
3312         default:
3313           success = false;
3314           break;
3315         }
3316       }
3317 
3318       if (success) {
3319         nub_addr_t addr =
3320             DNBProcessMemoryAllocate(m_ctx.ProcessID(), size, permissions);
3321         if (addr != INVALID_NUB_ADDRESS) {
3322           std::ostringstream ostrm;
3323           ostrm << RAW_HEXBASE << addr;
3324           return SendPacket(ostrm.str());
3325         }
3326       }
3327     }
3328   }
3329   return SendPacket("E53");
3330 }
3331 
3332 // FORMAT: _mXXXXXX
3333 //      XXXXXX: address that was previously allocated
3334 //
3335 // RESPONSE: XXXXXX
3336 //      OK: address was deallocated
3337 //      EXX: error code
3338 //
3339 // EXAMPLES:
3340 //      _m123000
3341 
3342 rnb_err_t RNBRemote::HandlePacket_DeallocateMemory(const char *p) {
3343   StdStringExtractor packet(p);
3344   packet.SetFilePos(2); // Skip the "_m"
3345   nub_addr_t addr =
3346       packet.GetHexMaxU64(StdStringExtractor::BigEndian, INVALID_NUB_ADDRESS);
3347 
3348   if (addr != INVALID_NUB_ADDRESS) {
3349     if (DNBProcessMemoryDeallocate(m_ctx.ProcessID(), addr))
3350       return SendPacket("OK");
3351   }
3352   return SendPacket("E54");
3353 }
3354 
3355 // FORMAT: QSaveRegisterState;thread:TTTT;  (when thread suffix is supported)
3356 // FORMAT: QSaveRegisterState               (when thread suffix is NOT
3357 // supported)
3358 //      TTTT: thread ID in hex
3359 //
3360 // RESPONSE:
3361 //      SAVEID: Where SAVEID is a decimal number that represents the save ID
3362 //              that can be passed back into a "QRestoreRegisterState" packet
3363 //      EXX: error code
3364 //
3365 // EXAMPLES:
3366 //      QSaveRegisterState;thread:1E34;     (when thread suffix is supported)
3367 //      QSaveRegisterState                  (when thread suffix is NOT
3368 //      supported)
3369 
3370 rnb_err_t RNBRemote::HandlePacket_SaveRegisterState(const char *p) {
3371   nub_process_t pid = m_ctx.ProcessID();
3372   nub_thread_t tid = ExtractThreadIDFromThreadSuffix(p);
3373   if (tid == INVALID_NUB_THREAD) {
3374     if (m_thread_suffix_supported)
3375       return HandlePacket_ILLFORMED(
3376           __FILE__, __LINE__, p,
3377           "No thread specified in QSaveRegisterState packet");
3378     else
3379       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3380                                     "No thread was is set with the Hg packet");
3381   }
3382 
3383   // Get the register context size first by calling with NULL buffer
3384   const uint32_t save_id = DNBThreadSaveRegisterState(pid, tid);
3385   if (save_id != 0) {
3386     char response[64];
3387     snprintf(response, sizeof(response), "%u", save_id);
3388     return SendPacket(response);
3389   } else {
3390     return SendPacket("E75");
3391   }
3392 }
3393 // FORMAT: QRestoreRegisterState:SAVEID;thread:TTTT;  (when thread suffix is
3394 // supported)
3395 // FORMAT: QRestoreRegisterState:SAVEID               (when thread suffix is NOT
3396 // supported)
3397 //      TTTT: thread ID in hex
3398 //      SAVEID: a decimal number that represents the save ID that was
3399 //              returned from a call to "QSaveRegisterState"
3400 //
3401 // RESPONSE:
3402 //      OK: successfully restored registers for the specified thread
3403 //      EXX: error code
3404 //
3405 // EXAMPLES:
3406 //      QRestoreRegisterState:1;thread:1E34;     (when thread suffix is
3407 //      supported)
3408 //      QRestoreRegisterState:1                  (when thread suffix is NOT
3409 //      supported)
3410 
3411 rnb_err_t RNBRemote::HandlePacket_RestoreRegisterState(const char *p) {
3412   nub_process_t pid = m_ctx.ProcessID();
3413   nub_thread_t tid = ExtractThreadIDFromThreadSuffix(p);
3414   if (tid == INVALID_NUB_THREAD) {
3415     if (m_thread_suffix_supported)
3416       return HandlePacket_ILLFORMED(
3417           __FILE__, __LINE__, p,
3418           "No thread specified in QSaveRegisterState packet");
3419     else
3420       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3421                                     "No thread was is set with the Hg packet");
3422   }
3423 
3424   StdStringExtractor packet(p);
3425   packet.SetFilePos(
3426       strlen("QRestoreRegisterState:")); // Skip the "QRestoreRegisterState:"
3427   const uint32_t save_id = packet.GetU32(0);
3428 
3429   if (save_id != 0) {
3430     // Get the register context size first by calling with NULL buffer
3431     if (DNBThreadRestoreRegisterState(pid, tid, save_id))
3432       return SendPacket("OK");
3433     else
3434       return SendPacket("E77");
3435   }
3436   return SendPacket("E76");
3437 }
3438 
3439 static bool GetProcessNameFrom_vAttach(const char *&p,
3440                                        std::string &attach_name) {
3441   bool return_val = true;
3442   while (*p != '\0') {
3443     char smallbuf[3];
3444     smallbuf[0] = *p;
3445     smallbuf[1] = *(p + 1);
3446     smallbuf[2] = '\0';
3447 
3448     errno = 0;
3449     int ch = static_cast<int>(strtoul(smallbuf, NULL, 16));
3450     if (errno != 0 && ch == 0) {
3451       return_val = false;
3452       break;
3453     }
3454 
3455     attach_name.push_back(ch);
3456     p += 2;
3457   }
3458   return return_val;
3459 }
3460 
3461 rnb_err_t RNBRemote::HandlePacket_qSupported(const char *p) {
3462   uint32_t max_packet_size = 128 * 1024; // 128KBytes is a reasonable max packet
3463                                          // size--debugger can always use less
3464   char buf[256];
3465   snprintf(buf, sizeof(buf), "qXfer:features:read+;PacketSize=%x;qEcho+",
3466            max_packet_size);
3467 
3468   bool enable_compression = false;
3469   (void)enable_compression;
3470 
3471 #if (defined (TARGET_OS_WATCH) && TARGET_OS_WATCH == 1) \
3472     || (defined (TARGET_OS_IOS) && TARGET_OS_IOS == 1) \
3473     || (defined (TARGET_OS_TV) && TARGET_OS_TV == 1) \
3474     || (defined (TARGET_OS_BRIDGE) && TARGET_OS_BRIDGE == 1)
3475   enable_compression = true;
3476 #endif
3477 
3478   if (enable_compression) {
3479     strcat(buf, ";SupportedCompressions=lzfse,zlib-deflate,lz4,lzma;"
3480                 "DefaultCompressionMinSize=");
3481     char numbuf[16];
3482     snprintf(numbuf, sizeof(numbuf), "%zu", m_compression_minsize);
3483     numbuf[sizeof(numbuf) - 1] = '\0';
3484     strcat(buf, numbuf);
3485   }
3486 
3487   return SendPacket(buf);
3488 }
3489 
3490 static bool process_does_not_exist (nub_process_t pid) {
3491   std::vector<struct kinfo_proc> proc_infos;
3492   DNBGetAllInfos (proc_infos);
3493   const size_t infos_size = proc_infos.size();
3494   for (size_t i = 0; i < infos_size; i++)
3495     if (proc_infos[i].kp_proc.p_pid == pid)
3496       return false;
3497 
3498   return true; // process does not exist
3499 }
3500 
3501 // my_uid and process_uid are only initialized if this function
3502 // returns true -- that there was a uid mismatch -- and those
3503 // id's may want to be used in the error message.
3504 //
3505 // NOTE: this should only be called after process_does_not_exist().
3506 // This sysctl will return uninitialized data if we ask for a pid
3507 // that doesn't exist.  The alternative would be to fetch all
3508 // processes and step through to find the one we're looking for
3509 // (as process_does_not_exist() does).
3510 static bool attach_failed_due_to_uid_mismatch (nub_process_t pid,
3511                                                uid_t &my_uid,
3512                                                uid_t &process_uid) {
3513   struct kinfo_proc kinfo;
3514   int mib[] = {CTL_KERN, KERN_PROC, KERN_PROC_PID, pid};
3515   size_t len = sizeof(struct kinfo_proc);
3516   if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), &kinfo, &len, NULL, 0) != 0) {
3517     return false; // pid doesn't exist? can't check uid mismatch - it was fine
3518   }
3519   my_uid = geteuid();
3520   if (my_uid == 0)
3521     return false; // if we're root, attach didn't fail because of uid mismatch
3522   process_uid = kinfo.kp_eproc.e_ucred.cr_uid;
3523 
3524   // If my uid != the process' uid, then the attach probably failed because
3525   // of that.
3526   if (my_uid != process_uid)
3527     return true;
3528   else
3529     return false;
3530 }
3531 
3532 // NOTE: this should only be called after process_does_not_exist().
3533 // This sysctl will return uninitialized data if we ask for a pid
3534 // that doesn't exist.  The alternative would be to fetch all
3535 // processes and step through to find the one we're looking for
3536 // (as process_does_not_exist() does).
3537 static bool process_is_already_being_debugged (nub_process_t pid) {
3538   struct kinfo_proc kinfo;
3539   int mib[] = {CTL_KERN, KERN_PROC, KERN_PROC_PID, pid};
3540   size_t len = sizeof(struct kinfo_proc);
3541   if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), &kinfo, &len, NULL, 0) != 0) {
3542     return false; // pid doesn't exist? well, it's not being debugged...
3543   }
3544   if (kinfo.kp_proc.p_flag & P_TRACED)
3545     return true; // is being debugged already
3546   else
3547     return false;
3548 }
3549 
3550 // Test if this current login session has a connection to the
3551 // window server (if it does not have that access, it cannot ask
3552 // for debug permission by popping up a dialog box and attach
3553 // may fail outright).
3554 static bool login_session_has_gui_access () {
3555   // I believe this API only works on macOS.
3556 #if TARGET_OS_OSX == 0
3557   return true;
3558 #else
3559   auditinfo_addr_t info;
3560   getaudit_addr(&info, sizeof(info));
3561   if (info.ai_flags & AU_SESSION_FLAG_HAS_GRAPHIC_ACCESS)
3562     return true;
3563   else
3564     return false;
3565 #endif
3566 }
3567 
3568 // Checking for
3569 //
3570 //  {
3571 //    'class' : 'rule',
3572 //    'comment' : 'For use by Apple.  WARNING: administrators are advised
3573 //              not to modify this right.',
3574 //    'k-of-n' : '1',
3575 //    'rule' : [
3576 //      'is-admin',
3577 //      'is-developer',
3578 //      'authenticate-developer'
3579 //    ]
3580 //  }
3581 //
3582 // $ security authorizationdb read system.privilege.taskport.debug
3583 
3584 static bool developer_mode_enabled () {
3585   // This API only exists on macOS.
3586 #if TARGET_OS_OSX == 0
3587   return true;
3588 #else
3589  CFDictionaryRef currentRightDict = NULL;
3590  const char *debug_right = "system.privilege.taskport.debug";
3591  // caller must free dictionary initialized by the following
3592  OSStatus status = AuthorizationRightGet(debug_right, &currentRightDict);
3593  if (status != errAuthorizationSuccess) {
3594    // could not check authorization
3595    return true;
3596  }
3597 
3598  bool devmode_enabled = true;
3599 
3600  if (!CFDictionaryContainsKey(currentRightDict, CFSTR("k-of-n"))) {
3601    devmode_enabled = false;
3602  } else {
3603    CFNumberRef item = (CFNumberRef) CFDictionaryGetValue(currentRightDict, CFSTR("k-of-n"));
3604    if (item && CFGetTypeID(item) == CFNumberGetTypeID()) {
3605       int64_t num = 0;
3606       ::CFNumberGetValue(item, kCFNumberSInt64Type, &num);
3607       if (num != 1) {
3608         devmode_enabled = false;
3609       }
3610    } else {
3611      devmode_enabled = false;
3612    }
3613  }
3614 
3615  if (!CFDictionaryContainsKey(currentRightDict, CFSTR("class"))) {
3616    devmode_enabled = false;
3617  } else {
3618    CFStringRef item = (CFStringRef) CFDictionaryGetValue(currentRightDict, CFSTR("class"));
3619    if (item && CFGetTypeID(item) == CFStringGetTypeID()) {
3620      char tmpbuf[128];
3621      if (CFStringGetCString (item, tmpbuf, sizeof(tmpbuf), CFStringGetSystemEncoding())) {
3622        tmpbuf[sizeof (tmpbuf) - 1] = '\0';
3623        if (strcmp (tmpbuf, "rule") != 0) {
3624          devmode_enabled = false;
3625        }
3626      } else {
3627        devmode_enabled = false;
3628      }
3629    } else {
3630      devmode_enabled = false;
3631    }
3632  }
3633 
3634  if (!CFDictionaryContainsKey(currentRightDict, CFSTR("rule"))) {
3635    devmode_enabled = false;
3636  } else {
3637    CFArrayRef item = (CFArrayRef) CFDictionaryGetValue(currentRightDict, CFSTR("rule"));
3638    if (item && CFGetTypeID(item) == CFArrayGetTypeID()) {
3639      int count = ::CFArrayGetCount(item);
3640       CFRange range = CFRangeMake (0, count);
3641      if (!::CFArrayContainsValue (item, range, CFSTR("is-admin")))
3642        devmode_enabled = false;
3643      if (!::CFArrayContainsValue (item, range, CFSTR("is-developer")))
3644        devmode_enabled = false;
3645      if (!::CFArrayContainsValue (item, range, CFSTR("authenticate-developer")))
3646        devmode_enabled = false;
3647    } else {
3648      devmode_enabled = false;
3649    }
3650  }
3651  ::CFRelease(currentRightDict);
3652 
3653  return devmode_enabled;
3654 #endif // TARGET_OS_OSX
3655 }
3656 
3657 /*
3658  vAttach;pid
3659 
3660  Attach to a new process with the specified process ID. pid is a hexadecimal
3661  integer
3662  identifying the process. If the stub is currently controlling a process, it is
3663  killed. The attached process is stopped.This packet is only available in
3664  extended
3665  mode (see extended mode).
3666 
3667  Reply:
3668  "ENN"                      for an error
3669  "Any Stop Reply Packet"     for success
3670  */
3671 
3672 rnb_err_t RNBRemote::HandlePacket_v(const char *p) {
3673   if (strcmp(p, "vCont;c") == 0) {
3674     // Simple continue
3675     return RNBRemote::HandlePacket_c("c");
3676   } else if (strcmp(p, "vCont;s") == 0) {
3677     // Simple step
3678     return RNBRemote::HandlePacket_s("s");
3679   } else if (strstr(p, "vCont") == p) {
3680     DNBThreadResumeActions thread_actions;
3681     char *c = const_cast<char *>(p += strlen("vCont"));
3682     char *c_end = c + strlen(c);
3683     if (*c == '?')
3684       return SendPacket("vCont;c;C;s;S");
3685 
3686     while (c < c_end && *c == ';') {
3687       ++c; // Skip the semi-colon
3688       DNBThreadResumeAction thread_action;
3689       thread_action.tid = INVALID_NUB_THREAD;
3690       thread_action.state = eStateInvalid;
3691       thread_action.signal = 0;
3692       thread_action.addr = INVALID_NUB_ADDRESS;
3693 
3694       char action = *c++;
3695 
3696       switch (action) {
3697       case 'C':
3698         errno = 0;
3699         thread_action.signal = static_cast<int>(strtoul(c, &c, 16));
3700         if (errno != 0)
3701           return HandlePacket_ILLFORMED(
3702               __FILE__, __LINE__, p, "Could not parse signal in vCont packet");
3703       // Fall through to next case...
3704         [[clang::fallthrough]];
3705       case 'c':
3706         // Continue
3707         thread_action.state = eStateRunning;
3708         break;
3709 
3710       case 'S':
3711         errno = 0;
3712         thread_action.signal = static_cast<int>(strtoul(c, &c, 16));
3713         if (errno != 0)
3714           return HandlePacket_ILLFORMED(
3715               __FILE__, __LINE__, p, "Could not parse signal in vCont packet");
3716       // Fall through to next case...
3717         [[clang::fallthrough]];
3718       case 's':
3719         // Step
3720         thread_action.state = eStateStepping;
3721         break;
3722 
3723       default:
3724         HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3725                                "Unsupported action in vCont packet");
3726         break;
3727       }
3728       if (*c == ':') {
3729         errno = 0;
3730         thread_action.tid = strtoul(++c, &c, 16);
3731         if (errno != 0)
3732           return HandlePacket_ILLFORMED(
3733               __FILE__, __LINE__, p,
3734               "Could not parse thread number in vCont packet");
3735       }
3736 
3737       thread_actions.Append(thread_action);
3738     }
3739 
3740     // If a default action for all other threads wasn't mentioned
3741     // then we should stop the threads
3742     thread_actions.SetDefaultThreadActionIfNeeded(eStateStopped, 0);
3743     DNBProcessResume(m_ctx.ProcessID(), thread_actions.GetFirst(),
3744                      thread_actions.GetSize());
3745     return rnb_success;
3746   } else if (strstr(p, "vAttach") == p) {
3747     nub_process_t attach_pid =
3748         INVALID_NUB_PROCESS; // attach_pid will be set to 0 if the attach fails
3749     nub_process_t pid_attaching_to =
3750         INVALID_NUB_PROCESS; // pid_attaching_to is the original pid specified
3751     char err_str[1024] = {'\0'};
3752     std::string attach_name;
3753 
3754     if (DNBDebugserverIsTranslated()) {
3755       DNBLogError("debugserver is x86_64 binary running in translation, attach "
3756                   "failed.");
3757       std::string return_message = "E96;";
3758       return_message +=
3759           cstring_to_asciihex_string("debugserver is x86_64 binary running in "
3760                                      "translation, attached failed.");
3761       SendPacket(return_message.c_str());
3762       return rnb_err;
3763     }
3764 
3765     if (strstr(p, "vAttachWait;") == p) {
3766       p += strlen("vAttachWait;");
3767       if (!GetProcessNameFrom_vAttach(p, attach_name)) {
3768         return HandlePacket_ILLFORMED(
3769             __FILE__, __LINE__, p, "non-hex char in arg on 'vAttachWait' pkt");
3770       }
3771       DNBLog("[LaunchAttach] START %d vAttachWait for process name '%s'",
3772              getpid(), attach_name.c_str());
3773       const bool ignore_existing = true;
3774       attach_pid = DNBProcessAttachWait(
3775           &m_ctx, attach_name.c_str(), ignore_existing, NULL, 1000, err_str,
3776           sizeof(err_str), RNBRemoteShouldCancelCallback);
3777 
3778     } else if (strstr(p, "vAttachOrWait;") == p) {
3779       p += strlen("vAttachOrWait;");
3780       if (!GetProcessNameFrom_vAttach(p, attach_name)) {
3781         return HandlePacket_ILLFORMED(
3782             __FILE__, __LINE__, p,
3783             "non-hex char in arg on 'vAttachOrWait' pkt");
3784       }
3785       const bool ignore_existing = false;
3786       DNBLog("[LaunchAttach] START %d vAttachWaitOrWait for process name "
3787              "'%s'",
3788              getpid(), attach_name.c_str());
3789       attach_pid = DNBProcessAttachWait(
3790           &m_ctx, attach_name.c_str(), ignore_existing, NULL, 1000, err_str,
3791           sizeof(err_str), RNBRemoteShouldCancelCallback);
3792     } else if (strstr(p, "vAttachName;") == p) {
3793       p += strlen("vAttachName;");
3794       if (!GetProcessNameFrom_vAttach(p, attach_name)) {
3795         return HandlePacket_ILLFORMED(
3796             __FILE__, __LINE__, p, "non-hex char in arg on 'vAttachName' pkt");
3797       }
3798 
3799       DNBLog("[LaunchAttach] START %d vAttachName attach to process name "
3800              "'%s'",
3801              getpid(), attach_name.c_str());
3802       attach_pid = DNBProcessAttachByName(attach_name.c_str(), NULL,
3803                                           Context().GetUnmaskSignals(), err_str,
3804                                           sizeof(err_str));
3805 
3806     } else if (strstr(p, "vAttach;") == p) {
3807       p += strlen("vAttach;");
3808       char *end = NULL;
3809       pid_attaching_to = static_cast<int>(
3810           strtoul(p, &end, 16)); // PID will be in hex, so use base 16 to decode
3811       if (p != end && *end == '\0') {
3812         // Wait at most 30 second for attach
3813         struct timespec attach_timeout_abstime;
3814         DNBTimer::OffsetTimeOfDay(&attach_timeout_abstime, 30, 0);
3815         DNBLog("[LaunchAttach] START %d vAttach to pid %d", getpid(),
3816                pid_attaching_to);
3817         attach_pid = DNBProcessAttach(pid_attaching_to, &attach_timeout_abstime,
3818                                       false, err_str, sizeof(err_str));
3819       }
3820     } else {
3821       return HandlePacket_UNIMPLEMENTED(p);
3822     }
3823 
3824     if (attach_pid != INVALID_NUB_PROCESS) {
3825       if (m_ctx.ProcessID() != attach_pid)
3826         m_ctx.SetProcessID(attach_pid);
3827       DNBLog("Successfully attached to pid %d", attach_pid);
3828       // Send a stop reply packet to indicate we successfully attached!
3829       NotifyThatProcessStopped();
3830       return rnb_success;
3831     } else {
3832       DNBLogError("Attach failed");
3833       m_ctx.LaunchStatus().SetError(-1, DNBError::Generic);
3834       if (err_str[0])
3835         m_ctx.LaunchStatus().SetErrorString(err_str);
3836       else
3837         m_ctx.LaunchStatus().SetErrorString("attach failed");
3838 
3839       if (pid_attaching_to == INVALID_NUB_PROCESS && !attach_name.empty()) {
3840         pid_attaching_to = DNBProcessGetPIDByName(attach_name.c_str());
3841       }
3842 
3843       // attach_pid is INVALID_NUB_PROCESS - we did not succeed in attaching
3844       // if the original request, pid_attaching_to, is available, see if we
3845       // can figure out why we couldn't attach.  Return an informative error
3846       // string to lldb.
3847 
3848       if (pid_attaching_to != INVALID_NUB_PROCESS) {
3849         // The order of these checks is important.
3850         if (process_does_not_exist (pid_attaching_to)) {
3851           DNBLogError("Tried to attach to pid that doesn't exist");
3852           std::string return_message = "E96;";
3853           return_message += cstring_to_asciihex_string("no such process.");
3854           return SendPacket(return_message.c_str());
3855         }
3856         if (process_is_already_being_debugged (pid_attaching_to)) {
3857           DNBLogError("Tried to attach to process already being debugged");
3858           std::string return_message = "E96;";
3859           return_message += cstring_to_asciihex_string("tried to attach to "
3860                                            "process already being debugged");
3861           return SendPacket(return_message.c_str());
3862         }
3863         uid_t my_uid, process_uid;
3864         if (attach_failed_due_to_uid_mismatch (pid_attaching_to,
3865                                                my_uid, process_uid)) {
3866           std::string my_username = "uid " + std::to_string (my_uid);
3867           std::string process_username = "uid " + std::to_string (process_uid);
3868           struct passwd *pw = getpwuid (my_uid);
3869           if (pw && pw->pw_name) {
3870             my_username = pw->pw_name;
3871           }
3872           pw = getpwuid (process_uid);
3873           if (pw && pw->pw_name) {
3874             process_username = pw->pw_name;
3875           }
3876           DNBLogError("Tried to attach to process with uid mismatch");
3877           std::string return_message = "E96;";
3878           std::string msg = "tried to attach to process as user '"
3879                             + my_username + "' and process is running "
3880                             "as user '" + process_username + "'";
3881           return_message += cstring_to_asciihex_string(msg.c_str());
3882           return SendPacket(return_message.c_str());
3883         }
3884         if (!login_session_has_gui_access() && !developer_mode_enabled()) {
3885           DNBLogError("Developer mode is not enabled and this is a "
3886                       "non-interactive session");
3887           std::string return_message = "E96;";
3888           return_message += cstring_to_asciihex_string("developer mode is "
3889                                            "not enabled on this machine "
3890                                            "and this is a non-interactive "
3891                                            "debug session.");
3892           return SendPacket(return_message.c_str());
3893         }
3894         if (!login_session_has_gui_access()) {
3895           DNBLogError("This is a non-interactive session");
3896           std::string return_message = "E96;";
3897           return_message += cstring_to_asciihex_string("this is a "
3898                                            "non-interactive debug session, "
3899                                            "cannot get permission to debug "
3900                                            "processes.");
3901           return SendPacket(return_message.c_str());
3902         }
3903       }
3904 
3905       std::string error_explainer = "attach failed";
3906       if (err_str[0] != '\0') {
3907         // This is not a super helpful message for end users
3908         if (strcmp (err_str, "unable to start the exception thread") == 0) {
3909           snprintf (err_str, sizeof (err_str) - 1,
3910                     "Not allowed to attach to process.  Look in the console "
3911                     "messages (Console.app), near the debugserver entries, "
3912                     "when the attach failed.  The subsystem that denied "
3913                     "the attach permission will likely have logged an "
3914                     "informative message about why it was denied.");
3915           err_str[sizeof (err_str) - 1] = '\0';
3916         }
3917         error_explainer += " (";
3918         error_explainer += err_str;
3919         error_explainer += ")";
3920       }
3921       std::string default_return_msg = "E96;";
3922       default_return_msg += cstring_to_asciihex_string
3923                               (error_explainer.c_str());
3924       SendPacket (default_return_msg.c_str());
3925       DNBLogError("Attach failed: \"%s\".", err_str);
3926       return rnb_err;
3927     }
3928   }
3929 
3930   // All other failures come through here
3931   return HandlePacket_UNIMPLEMENTED(p);
3932 }
3933 
3934 /* 'T XX' -- status of thread
3935  Check if the specified thread is alive.
3936  The thread number is in hex?  */
3937 
3938 rnb_err_t RNBRemote::HandlePacket_T(const char *p) {
3939   p++;
3940   if (p == NULL || *p == '\0') {
3941     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3942                                   "No thread specified in T packet");
3943   }
3944   if (!m_ctx.HasValidProcessID()) {
3945     return SendPacket("E15");
3946   }
3947   errno = 0;
3948   nub_thread_t tid = strtoul(p, NULL, 16);
3949   if (errno != 0 && tid == 0) {
3950     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3951                                   "Could not parse thread number in T packet");
3952   }
3953 
3954   nub_state_t state = DNBThreadGetState(m_ctx.ProcessID(), tid);
3955   if (state == eStateInvalid || state == eStateExited ||
3956       state == eStateCrashed) {
3957     return SendPacket("E16");
3958   }
3959 
3960   return SendPacket("OK");
3961 }
3962 
3963 rnb_err_t RNBRemote::HandlePacket_z(const char *p) {
3964   if (p == NULL || *p == '\0')
3965     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3966                                   "No thread specified in z packet");
3967 
3968   if (!m_ctx.HasValidProcessID())
3969     return SendPacket("E15");
3970 
3971   char packet_cmd = *p++;
3972   char break_type = *p++;
3973 
3974   if (*p++ != ',')
3975     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3976                                   "Comma separator missing in z packet");
3977 
3978   char *c = NULL;
3979   nub_process_t pid = m_ctx.ProcessID();
3980   errno = 0;
3981   nub_addr_t addr = strtoull(p, &c, 16);
3982   if (errno != 0 && addr == 0)
3983     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3984                                   "Invalid address in z packet");
3985   p = c;
3986   if (*p++ != ',')
3987     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3988                                   "Comma separator missing in z packet");
3989 
3990   errno = 0;
3991   auto byte_size = strtoul(p, &c, 16);
3992   if (errno != 0 && byte_size == 0)
3993     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
3994                                   "Invalid length in z packet");
3995 
3996   if (packet_cmd == 'Z') {
3997     // set
3998     switch (break_type) {
3999     case '0': // set software breakpoint
4000     case '1': // set hardware breakpoint
4001     {
4002       // gdb can send multiple Z packets for the same address and
4003       // these calls must be ref counted.
4004       bool hardware = (break_type == '1');
4005 
4006       if (DNBBreakpointSet(pid, addr, byte_size, hardware)) {
4007         // We successfully created a breakpoint, now lets full out
4008         // a ref count structure with the breakID and add it to our
4009         // map.
4010         return SendPacket("OK");
4011       } else {
4012         // We failed to set the software breakpoint
4013         return SendPacket("E09");
4014       }
4015     } break;
4016 
4017     case '2': // set write watchpoint
4018     case '3': // set read watchpoint
4019     case '4': // set access watchpoint
4020     {
4021       bool hardware = true;
4022       uint32_t watch_flags = 0;
4023       if (break_type == '2')
4024         watch_flags = WATCH_TYPE_WRITE;
4025       else if (break_type == '3')
4026         watch_flags = WATCH_TYPE_READ;
4027       else
4028         watch_flags = WATCH_TYPE_READ | WATCH_TYPE_WRITE;
4029 
4030       if (DNBWatchpointSet(pid, addr, byte_size, watch_flags, hardware)) {
4031         return SendPacket("OK");
4032       } else {
4033         // We failed to set the watchpoint
4034         return SendPacket("E09");
4035       }
4036     } break;
4037 
4038     default:
4039       break;
4040     }
4041   } else if (packet_cmd == 'z') {
4042     // remove
4043     switch (break_type) {
4044     case '0': // remove software breakpoint
4045     case '1': // remove hardware breakpoint
4046       if (DNBBreakpointClear(pid, addr)) {
4047         return SendPacket("OK");
4048       } else {
4049         return SendPacket("E08");
4050       }
4051       break;
4052 
4053     case '2': // remove write watchpoint
4054     case '3': // remove read watchpoint
4055     case '4': // remove access watchpoint
4056       if (DNBWatchpointClear(pid, addr)) {
4057         return SendPacket("OK");
4058       } else {
4059         return SendPacket("E08");
4060       }
4061       break;
4062 
4063     default:
4064       break;
4065     }
4066   }
4067   return HandlePacket_UNIMPLEMENTED(p);
4068 }
4069 
4070 // Extract the thread number from the thread suffix that might be appended to
4071 // thread specific packets. This will only be enabled if
4072 // m_thread_suffix_supported
4073 // is true.
4074 nub_thread_t RNBRemote::ExtractThreadIDFromThreadSuffix(const char *p) {
4075   if (m_thread_suffix_supported) {
4076     nub_thread_t tid = INVALID_NUB_THREAD;
4077     if (p) {
4078       const char *tid_cstr = strstr(p, "thread:");
4079       if (tid_cstr) {
4080         tid_cstr += strlen("thread:");
4081         tid = strtoul(tid_cstr, NULL, 16);
4082       }
4083     }
4084     return tid;
4085   }
4086   return GetCurrentThread();
4087 }
4088 
4089 /* 'p XX'
4090  print the contents of register X */
4091 
4092 rnb_err_t RNBRemote::HandlePacket_p(const char *p) {
4093   if (g_num_reg_entries == 0)
4094     InitializeRegisters();
4095 
4096   if (p == NULL || *p == '\0') {
4097     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4098                                   "No thread specified in p packet");
4099   }
4100   if (!m_ctx.HasValidProcessID()) {
4101     return SendPacket("E15");
4102   }
4103   nub_process_t pid = m_ctx.ProcessID();
4104   errno = 0;
4105   char *tid_cstr = NULL;
4106   uint32_t reg = static_cast<uint32_t>(strtoul(p + 1, &tid_cstr, 16));
4107   if (errno != 0 && reg == 0) {
4108     return HandlePacket_ILLFORMED(
4109         __FILE__, __LINE__, p, "Could not parse register number in p packet");
4110   }
4111 
4112   nub_thread_t tid = ExtractThreadIDFromThreadSuffix(tid_cstr);
4113   if (tid == INVALID_NUB_THREAD)
4114     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4115                                   "No thread specified in p packet");
4116 
4117   const register_map_entry_t *reg_entry;
4118 
4119   if (reg < g_num_reg_entries)
4120     reg_entry = &g_reg_entries[reg];
4121   else
4122     reg_entry = NULL;
4123 
4124   std::ostringstream ostrm;
4125   if (reg_entry == NULL) {
4126     DNBLogError(
4127         "RNBRemote::HandlePacket_p(%s): unknown register number %u requested\n",
4128         p, reg);
4129     ostrm << "00000000";
4130   } else if (reg_entry->nub_info.reg == (uint32_t)-1) {
4131     if (reg_entry->nub_info.size > 0) {
4132       std::basic_string<uint8_t> zeros(reg_entry->nub_info.size, '\0');
4133       append_hex_value(ostrm, zeros.data(), zeros.size(), false);
4134     }
4135   } else {
4136     register_value_in_hex_fixed_width(ostrm, pid, tid, reg_entry, NULL);
4137   }
4138   return SendPacket(ostrm.str());
4139 }
4140 
4141 /* 'Pnn=rrrrr'
4142  Set register number n to value r.
4143  n and r are hex strings.  */
4144 
4145 rnb_err_t RNBRemote::HandlePacket_P(const char *p) {
4146   if (g_num_reg_entries == 0)
4147     InitializeRegisters();
4148 
4149   if (p == NULL || *p == '\0') {
4150     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p, "Empty P packet");
4151   }
4152   if (!m_ctx.HasValidProcessID()) {
4153     return SendPacket("E28");
4154   }
4155 
4156   nub_process_t pid = m_ctx.ProcessID();
4157 
4158   StdStringExtractor packet(p);
4159 
4160   const char cmd_char = packet.GetChar();
4161   // Register ID is always in big endian
4162   const uint32_t reg = packet.GetHexMaxU32(false, UINT32_MAX);
4163   const char equal_char = packet.GetChar();
4164 
4165   if (cmd_char != 'P')
4166     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4167                                   "Improperly formed P packet");
4168 
4169   if (reg == UINT32_MAX)
4170     return SendPacket("E29");
4171 
4172   if (equal_char != '=')
4173     return SendPacket("E30");
4174 
4175   const register_map_entry_t *reg_entry;
4176 
4177   if (reg >= g_num_reg_entries)
4178     return SendPacket("E47");
4179 
4180   reg_entry = &g_reg_entries[reg];
4181 
4182   if (reg_entry->nub_info.set == (uint32_t)-1 &&
4183       reg_entry->nub_info.reg == (uint32_t)-1) {
4184     DNBLogError(
4185         "RNBRemote::HandlePacket_P(%s): unknown register number %u requested\n",
4186         p, reg);
4187     return SendPacket("E48");
4188   }
4189 
4190   DNBRegisterValue reg_value;
4191   reg_value.info = reg_entry->nub_info;
4192   packet.GetHexBytes(reg_value.value.v_sint8, reg_entry->nub_info.size, 0xcc);
4193 
4194   nub_thread_t tid = ExtractThreadIDFromThreadSuffix(p);
4195   if (tid == INVALID_NUB_THREAD)
4196     return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4197                                   "No thread specified in p packet");
4198 
4199   if (!DNBThreadSetRegisterValueByID(pid, tid, reg_entry->nub_info.set,
4200                                      reg_entry->nub_info.reg, &reg_value)) {
4201     return SendPacket("E32");
4202   }
4203   return SendPacket("OK");
4204 }
4205 
4206 /* 'c [addr]'
4207  Continue, optionally from a specified address. */
4208 
4209 rnb_err_t RNBRemote::HandlePacket_c(const char *p) {
4210   const nub_process_t pid = m_ctx.ProcessID();
4211 
4212   if (pid == INVALID_NUB_PROCESS)
4213     return SendPacket("E23");
4214 
4215   DNBThreadResumeAction action = {INVALID_NUB_THREAD, eStateRunning, 0,
4216                                   INVALID_NUB_ADDRESS};
4217 
4218   if (*(p + 1) != '\0') {
4219     action.tid = GetContinueThread();
4220     errno = 0;
4221     action.addr = strtoull(p + 1, NULL, 16);
4222     if (errno != 0 && action.addr == 0)
4223       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4224                                     "Could not parse address in c packet");
4225   }
4226 
4227   DNBThreadResumeActions thread_actions;
4228   thread_actions.Append(action);
4229   thread_actions.SetDefaultThreadActionIfNeeded(eStateRunning, 0);
4230   if (!DNBProcessResume(pid, thread_actions.GetFirst(),
4231                         thread_actions.GetSize()))
4232     return SendPacket("E25");
4233   // Don't send an "OK" packet; response is the stopped/exited message.
4234   return rnb_success;
4235 }
4236 
4237 rnb_err_t RNBRemote::HandlePacket_MemoryRegionInfo(const char *p) {
4238   /* This packet will find memory attributes (e.g. readable, writable,
4239      executable, stack, jitted code)
4240      for the memory region containing a given address and return that
4241      information.
4242 
4243      Users of this packet must be prepared for three results:
4244 
4245          Region information is returned
4246          Region information is unavailable for this address because the address
4247      is in unmapped memory
4248          Region lookup cannot be performed on this platform or process is not
4249      yet launched
4250          This packet isn't implemented
4251 
4252      Examples of use:
4253         qMemoryRegionInfo:3a55140
4254         start:3a50000,size:100000,permissions:rwx
4255 
4256         qMemoryRegionInfo:0
4257         error:address in unmapped region
4258 
4259         qMemoryRegionInfo:3a551140   (on a different platform)
4260         error:region lookup cannot be performed
4261 
4262         qMemoryRegionInfo
4263         OK                   // this packet is implemented by the remote nub
4264   */
4265 
4266   p += sizeof("qMemoryRegionInfo") - 1;
4267   if (*p == '\0')
4268     return SendPacket("OK");
4269   if (*p++ != ':')
4270     return SendPacket("E67");
4271   if (*p == '0' && (*(p + 1) == 'x' || *(p + 1) == 'X'))
4272     p += 2;
4273 
4274   errno = 0;
4275   uint64_t address = strtoul(p, NULL, 16);
4276   if (errno != 0 && address == 0) {
4277     return HandlePacket_ILLFORMED(
4278         __FILE__, __LINE__, p, "Invalid address in qMemoryRegionInfo packet");
4279   }
4280 
4281   DNBRegionInfo region_info;
4282   DNBProcessMemoryRegionInfo(m_ctx.ProcessID(), address, &region_info);
4283   std::ostringstream ostrm;
4284 
4285   // start:3a50000,size:100000,permissions:rwx
4286   ostrm << "start:" << std::hex << region_info.addr << ';';
4287 
4288   if (region_info.size > 0)
4289     ostrm << "size:" << std::hex << region_info.size << ';';
4290 
4291   if (region_info.permissions) {
4292     ostrm << "permissions:";
4293 
4294     if (region_info.permissions & eMemoryPermissionsReadable)
4295       ostrm << 'r';
4296     if (region_info.permissions & eMemoryPermissionsWritable)
4297       ostrm << 'w';
4298     if (region_info.permissions & eMemoryPermissionsExecutable)
4299       ostrm << 'x';
4300     ostrm << ';';
4301 
4302     ostrm << "dirty-pages:";
4303     if (region_info.dirty_pages.size() > 0) {
4304       bool first = true;
4305       for (nub_addr_t addr : region_info.dirty_pages) {
4306         if (!first)
4307           ostrm << ",";
4308         first = false;
4309         ostrm << "0x" << std::hex << addr;
4310       }
4311     }
4312     ostrm << ";";
4313   }
4314   return SendPacket(ostrm.str());
4315 }
4316 
4317 // qGetProfileData;scan_type:0xYYYYYYY
4318 rnb_err_t RNBRemote::HandlePacket_GetProfileData(const char *p) {
4319   nub_process_t pid = m_ctx.ProcessID();
4320   if (pid == INVALID_NUB_PROCESS)
4321     return SendPacket("OK");
4322 
4323   StdStringExtractor packet(p += sizeof("qGetProfileData"));
4324   DNBProfileDataScanType scan_type = eProfileAll;
4325   std::string name;
4326   std::string value;
4327   while (packet.GetNameColonValue(name, value)) {
4328     if (name == "scan_type") {
4329       std::istringstream iss(value);
4330       uint32_t int_value = 0;
4331       if (iss >> std::hex >> int_value) {
4332         scan_type = (DNBProfileDataScanType)int_value;
4333       }
4334     }
4335   }
4336 
4337   std::string data = DNBProcessGetProfileData(pid, scan_type);
4338   if (!data.empty()) {
4339     return SendPacket(data.c_str());
4340   } else {
4341     return SendPacket("OK");
4342   }
4343 }
4344 
4345 // QSetEnableAsyncProfiling;enable:[0|1]:interval_usec:XXXXXX;scan_type:0xYYYYYYY
4346 rnb_err_t RNBRemote::HandlePacket_SetEnableAsyncProfiling(const char *p) {
4347   nub_process_t pid = m_ctx.ProcessID();
4348   if (pid == INVALID_NUB_PROCESS)
4349     return SendPacket("OK");
4350 
4351   StdStringExtractor packet(p += sizeof("QSetEnableAsyncProfiling"));
4352   bool enable = false;
4353   uint64_t interval_usec = 0;
4354   DNBProfileDataScanType scan_type = eProfileAll;
4355   std::string name;
4356   std::string value;
4357   while (packet.GetNameColonValue(name, value)) {
4358     if (name == "enable") {
4359       enable = strtoul(value.c_str(), NULL, 10) > 0;
4360     } else if (name == "interval_usec") {
4361       interval_usec = strtoul(value.c_str(), NULL, 10);
4362     } else if (name == "scan_type") {
4363       std::istringstream iss(value);
4364       uint32_t int_value = 0;
4365       if (iss >> std::hex >> int_value) {
4366         scan_type = (DNBProfileDataScanType)int_value;
4367       }
4368     }
4369   }
4370 
4371   if (interval_usec == 0) {
4372     enable = false;
4373   }
4374 
4375   DNBProcessSetEnableAsyncProfiling(pid, enable, interval_usec, scan_type);
4376   return SendPacket("OK");
4377 }
4378 
4379 // QEnableCompression:type:<COMPRESSION-TYPE>;minsize:<MINIMUM PACKET SIZE TO
4380 // COMPRESS>;
4381 //
4382 // type: must be a type previously reported by the qXfer:features:
4383 // SupportedCompressions list
4384 //
4385 // minsize: is optional; by default the qXfer:features:
4386 // DefaultCompressionMinSize value is used
4387 // debugserver may have a better idea of what a good minimum packet size to
4388 // compress is than lldb.
4389 
4390 rnb_err_t RNBRemote::HandlePacket_QEnableCompression(const char *p) {
4391   p += sizeof("QEnableCompression:") - 1;
4392 
4393   size_t new_compression_minsize = m_compression_minsize;
4394   const char *new_compression_minsize_str = strstr(p, "minsize:");
4395   if (new_compression_minsize_str) {
4396     new_compression_minsize_str += strlen("minsize:");
4397     errno = 0;
4398     new_compression_minsize = strtoul(new_compression_minsize_str, NULL, 10);
4399     if (errno != 0 || new_compression_minsize == ULONG_MAX) {
4400       new_compression_minsize = m_compression_minsize;
4401     }
4402   }
4403 
4404   if (strstr(p, "type:zlib-deflate;") != nullptr) {
4405     EnableCompressionNextSendPacket(compression_types::zlib_deflate);
4406     m_compression_minsize = new_compression_minsize;
4407     return SendPacket("OK");
4408   } else if (strstr(p, "type:lz4;") != nullptr) {
4409     EnableCompressionNextSendPacket(compression_types::lz4);
4410     m_compression_minsize = new_compression_minsize;
4411     return SendPacket("OK");
4412   } else if (strstr(p, "type:lzma;") != nullptr) {
4413     EnableCompressionNextSendPacket(compression_types::lzma);
4414     m_compression_minsize = new_compression_minsize;
4415     return SendPacket("OK");
4416   } else if (strstr(p, "type:lzfse;") != nullptr) {
4417     EnableCompressionNextSendPacket(compression_types::lzfse);
4418     m_compression_minsize = new_compression_minsize;
4419     return SendPacket("OK");
4420   }
4421 
4422   return SendPacket("E88");
4423 }
4424 
4425 rnb_err_t RNBRemote::HandlePacket_qSpeedTest(const char *p) {
4426   p += strlen("qSpeedTest:response_size:");
4427   char *end = NULL;
4428   errno = 0;
4429   uint64_t response_size = ::strtoul(p, &end, 16);
4430   if (errno != 0)
4431     return HandlePacket_ILLFORMED(
4432         __FILE__, __LINE__, p,
4433         "Didn't find response_size value at right offset");
4434   else if (*end == ';') {
4435     static char g_data[4 * 1024 * 1024 + 16];
4436     strcpy(g_data, "data:");
4437     memset(g_data + 5, 'a', response_size);
4438     g_data[response_size + 5] = '\0';
4439     return SendPacket(g_data);
4440   } else {
4441     return SendPacket("E79");
4442   }
4443 }
4444 
4445 rnb_err_t RNBRemote::HandlePacket_WatchpointSupportInfo(const char *p) {
4446   /* This packet simply returns the number of supported hardware watchpoints.
4447 
4448      Examples of use:
4449         qWatchpointSupportInfo:
4450         num:4
4451 
4452         qWatchpointSupportInfo
4453         OK                   // this packet is implemented by the remote nub
4454   */
4455 
4456   p += sizeof("qWatchpointSupportInfo") - 1;
4457   if (*p == '\0')
4458     return SendPacket("OK");
4459   if (*p++ != ':')
4460     return SendPacket("E67");
4461 
4462   errno = 0;
4463   uint32_t num = DNBWatchpointGetNumSupportedHWP(m_ctx.ProcessID());
4464   std::ostringstream ostrm;
4465 
4466   // size:4
4467   ostrm << "num:" << std::dec << num << ';';
4468   return SendPacket(ostrm.str());
4469 }
4470 
4471 /* 'C sig [;addr]'
4472  Resume with signal sig, optionally at address addr.  */
4473 
4474 rnb_err_t RNBRemote::HandlePacket_C(const char *p) {
4475   const nub_process_t pid = m_ctx.ProcessID();
4476 
4477   if (pid == INVALID_NUB_PROCESS)
4478     return SendPacket("E36");
4479 
4480   DNBThreadResumeAction action = {INVALID_NUB_THREAD, eStateRunning, 0,
4481                                   INVALID_NUB_ADDRESS};
4482   int process_signo = -1;
4483   if (*(p + 1) != '\0') {
4484     action.tid = GetContinueThread();
4485     char *end = NULL;
4486     errno = 0;
4487     process_signo = static_cast<int>(strtoul(p + 1, &end, 16));
4488     if (errno != 0)
4489       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4490                                     "Could not parse signal in C packet");
4491     else if (*end == ';') {
4492       errno = 0;
4493       action.addr = strtoull(end + 1, NULL, 16);
4494       if (errno != 0 && action.addr == 0)
4495         return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4496                                       "Could not parse address in C packet");
4497     }
4498   }
4499 
4500   DNBThreadResumeActions thread_actions;
4501   thread_actions.Append(action);
4502   thread_actions.SetDefaultThreadActionIfNeeded(eStateRunning, action.signal);
4503   if (!DNBProcessSignal(pid, process_signo))
4504     return SendPacket("E52");
4505   if (!DNBProcessResume(pid, thread_actions.GetFirst(),
4506                         thread_actions.GetSize()))
4507     return SendPacket("E38");
4508   /* Don't send an "OK" packet; response is the stopped/exited message.  */
4509   return rnb_success;
4510 }
4511 
4512 // 'D' packet
4513 // Detach from gdb.
4514 rnb_err_t RNBRemote::HandlePacket_D(const char *p) {
4515   if (m_ctx.HasValidProcessID()) {
4516     DNBLog("detaching from pid %u due to D packet", m_ctx.ProcessID());
4517     if (DNBProcessDetach(m_ctx.ProcessID()))
4518       SendPacket("OK");
4519     else {
4520       DNBLog("error while detaching from pid %u due to D packet",
4521              m_ctx.ProcessID());
4522       SendPacket("E");
4523     }
4524   } else {
4525     SendPacket("E");
4526   }
4527   return rnb_success;
4528 }
4529 
4530 /* 'k'
4531  Kill the inferior process.  */
4532 
4533 rnb_err_t RNBRemote::HandlePacket_k(const char *p) {
4534   DNBLog("Got a 'k' packet, killing the inferior process.");
4535   // No response to should be sent to the kill packet
4536   if (m_ctx.HasValidProcessID())
4537     DNBProcessKill(m_ctx.ProcessID());
4538   SendPacket("X09");
4539   return rnb_success;
4540 }
4541 
4542 rnb_err_t RNBRemote::HandlePacket_stop_process(const char *p) {
4543 //#define TEST_EXIT_ON_INTERRUPT // This should only be uncommented to test
4544 //exiting on interrupt
4545 #if defined(TEST_EXIT_ON_INTERRUPT)
4546   rnb_err_t err = HandlePacket_k(p);
4547   m_comm.Disconnect(true);
4548   return err;
4549 #else
4550   if (!DNBProcessInterrupt(m_ctx.ProcessID())) {
4551     // If we failed to interrupt the process, then send a stop
4552     // reply packet as the process was probably already stopped
4553     DNBLogThreaded("RNBRemote::HandlePacket_stop_process() sending extra stop "
4554                    "reply because DNBProcessInterrupt returned false");
4555     HandlePacket_last_signal(NULL);
4556   }
4557   return rnb_success;
4558 #endif
4559 }
4560 
4561 /* 's'
4562  Step the inferior process.  */
4563 
4564 rnb_err_t RNBRemote::HandlePacket_s(const char *p) {
4565   const nub_process_t pid = m_ctx.ProcessID();
4566   if (pid == INVALID_NUB_PROCESS)
4567     return SendPacket("E32");
4568 
4569   // Hardware supported stepping not supported on arm
4570   nub_thread_t tid = GetContinueThread();
4571   if (tid == 0 || tid == (nub_thread_t)-1)
4572     tid = GetCurrentThread();
4573 
4574   if (tid == INVALID_NUB_THREAD)
4575     return SendPacket("E33");
4576 
4577   DNBThreadResumeActions thread_actions;
4578   thread_actions.AppendAction(tid, eStateStepping);
4579 
4580   // Make all other threads stop when we are stepping
4581   thread_actions.SetDefaultThreadActionIfNeeded(eStateStopped, 0);
4582   if (!DNBProcessResume(pid, thread_actions.GetFirst(),
4583                         thread_actions.GetSize()))
4584     return SendPacket("E49");
4585   // Don't send an "OK" packet; response is the stopped/exited message.
4586   return rnb_success;
4587 }
4588 
4589 /* 'S sig [;addr]'
4590  Step with signal sig, optionally at address addr.  */
4591 
4592 rnb_err_t RNBRemote::HandlePacket_S(const char *p) {
4593   const nub_process_t pid = m_ctx.ProcessID();
4594   if (pid == INVALID_NUB_PROCESS)
4595     return SendPacket("E36");
4596 
4597   DNBThreadResumeAction action = {INVALID_NUB_THREAD, eStateStepping, 0,
4598                                   INVALID_NUB_ADDRESS};
4599 
4600   if (*(p + 1) != '\0') {
4601     char *end = NULL;
4602     errno = 0;
4603     action.signal = static_cast<int>(strtoul(p + 1, &end, 16));
4604     if (errno != 0)
4605       return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4606                                     "Could not parse signal in S packet");
4607     else if (*end == ';') {
4608       errno = 0;
4609       action.addr = strtoull(end + 1, NULL, 16);
4610       if (errno != 0 && action.addr == 0) {
4611         return HandlePacket_ILLFORMED(__FILE__, __LINE__, p,
4612                                       "Could not parse address in S packet");
4613       }
4614     }
4615   }
4616 
4617   action.tid = GetContinueThread();
4618   if (action.tid == 0 || action.tid == (nub_thread_t)-1)
4619     return SendPacket("E40");
4620 
4621   nub_state_t tstate = DNBThreadGetState(pid, action.tid);
4622   if (tstate == eStateInvalid || tstate == eStateExited)
4623     return SendPacket("E37");
4624 
4625   DNBThreadResumeActions thread_actions;
4626   thread_actions.Append(action);
4627 
4628   // Make all other threads stop when we are stepping
4629   thread_actions.SetDefaultThreadActionIfNeeded(eStateStopped, 0);
4630   if (!DNBProcessResume(pid, thread_actions.GetFirst(),
4631                         thread_actions.GetSize()))
4632     return SendPacket("E39");
4633 
4634   // Don't send an "OK" packet; response is the stopped/exited message.
4635   return rnb_success;
4636 }
4637 
4638 static const char *GetArchName(const uint32_t cputype,
4639                                const uint32_t cpusubtype) {
4640   switch (cputype) {
4641   case CPU_TYPE_ARM:
4642     switch (cpusubtype) {
4643     case 5:
4644       return "armv4";
4645     case 6:
4646       return "armv6";
4647     case 7:
4648       return "armv5t";
4649     case 8:
4650       return "xscale";
4651     case 9:
4652       return "armv7";
4653     case 10:
4654       return "armv7f";
4655     case 11:
4656       return "armv7s";
4657     case 12:
4658       return "armv7k";
4659     case 14:
4660       return "armv6m";
4661     case 15:
4662       return "armv7m";
4663     case 16:
4664       return "armv7em";
4665     default:
4666       return "arm";
4667     }
4668     break;
4669   case CPU_TYPE_ARM64:
4670     return "arm64";
4671   case CPU_TYPE_ARM64_32:
4672     return "arm64_32";
4673   case CPU_TYPE_I386:
4674     return "i386";
4675   case CPU_TYPE_X86_64:
4676     switch (cpusubtype) {
4677     default:
4678       return "x86_64";
4679     case 8:
4680       return "x86_64h";
4681     }
4682     break;
4683   }
4684   return NULL;
4685 }
4686 
4687 static bool GetHostCPUType(uint32_t &cputype, uint32_t &cpusubtype,
4688                            uint32_t &is_64_bit_capable, bool &promoted_to_64) {
4689   static uint32_t g_host_cputype = 0;
4690   static uint32_t g_host_cpusubtype = 0;
4691   static uint32_t g_is_64_bit_capable = 0;
4692   static bool g_promoted_to_64 = false;
4693 
4694   if (g_host_cputype == 0) {
4695     g_promoted_to_64 = false;
4696     size_t len = sizeof(uint32_t);
4697     if (::sysctlbyname("hw.cputype", &g_host_cputype, &len, NULL, 0) == 0) {
4698       len = sizeof(uint32_t);
4699       if (::sysctlbyname("hw.cpu64bit_capable", &g_is_64_bit_capable, &len,
4700                          NULL, 0) == 0) {
4701         if (g_is_64_bit_capable && ((g_host_cputype & CPU_ARCH_ABI64) == 0)) {
4702           g_promoted_to_64 = true;
4703           g_host_cputype |= CPU_ARCH_ABI64;
4704         }
4705       }
4706 #if defined (TARGET_OS_WATCH) && TARGET_OS_WATCH == 1
4707       if (g_host_cputype == CPU_TYPE_ARM64 && sizeof (void*) == 4)
4708         g_host_cputype = CPU_TYPE_ARM64_32;
4709 #endif
4710     }
4711 
4712     len = sizeof(uint32_t);
4713     if (::sysctlbyname("hw.cpusubtype", &g_host_cpusubtype, &len, NULL, 0) ==
4714         0) {
4715       if (g_promoted_to_64 && g_host_cputype == CPU_TYPE_X86_64 &&
4716           g_host_cpusubtype == CPU_SUBTYPE_486)
4717         g_host_cpusubtype = CPU_SUBTYPE_X86_64_ALL;
4718     }
4719 #if defined (TARGET_OS_WATCH) && TARGET_OS_WATCH == 1
4720     // on arm64_32 devices, the machine's native cpu type is
4721     // CPU_TYPE_ARM64 and subtype is 2 indicating arm64e.
4722     // But we change the cputype to CPU_TYPE_ARM64_32 because
4723     // the user processes are all ILP32 processes today.
4724     // We also need to rewrite the cpusubtype so we vend
4725     // a valid cputype + cpusubtype combination.
4726     if (g_host_cputype == CPU_TYPE_ARM64_32)
4727       g_host_cpusubtype = CPU_SUBTYPE_ARM64_32_V8;
4728 #endif
4729   }
4730 
4731   cputype = g_host_cputype;
4732   cpusubtype = g_host_cpusubtype;
4733   is_64_bit_capable = g_is_64_bit_capable;
4734   promoted_to_64 = g_promoted_to_64;
4735   return g_host_cputype != 0;
4736 }
4737 
4738 static bool GetAddressingBits(uint32_t &addressing_bits) {
4739   static uint32_t g_addressing_bits = 0;
4740   static bool g_tried_addressing_bits_syscall = false;
4741   if (g_tried_addressing_bits_syscall == false) {
4742     size_t len = sizeof (uint32_t);
4743     if (::sysctlbyname("machdep.virtual_address_size",
4744           &g_addressing_bits, &len, NULL, 0) != 0) {
4745       g_addressing_bits = 0;
4746     }
4747   }
4748   g_tried_addressing_bits_syscall = true;
4749   addressing_bits = g_addressing_bits;
4750   if (addressing_bits > 0)
4751     return true;
4752   else
4753     return false;
4754 }
4755 
4756 rnb_err_t RNBRemote::HandlePacket_qHostInfo(const char *p) {
4757   std::ostringstream strm;
4758 
4759   uint32_t cputype = 0;
4760   uint32_t cpusubtype = 0;
4761   uint32_t is_64_bit_capable = 0;
4762   bool promoted_to_64 = false;
4763   if (GetHostCPUType(cputype, cpusubtype, is_64_bit_capable, promoted_to_64)) {
4764     strm << "cputype:" << std::dec << cputype << ';';
4765     strm << "cpusubtype:" << std::dec << cpusubtype << ';';
4766   }
4767 
4768   uint32_t addressing_bits = 0;
4769   if (GetAddressingBits(addressing_bits)) {
4770     strm << "addressing_bits:" << std::dec << addressing_bits << ';';
4771   }
4772 
4773   // The OS in the triple should be "ios" or "macosx" which doesn't match our
4774   // "Darwin" which gets returned from "kern.ostype", so we need to hardcode
4775   // this for now.
4776   if (cputype == CPU_TYPE_ARM || cputype == CPU_TYPE_ARM64
4777       || cputype == CPU_TYPE_ARM64_32) {
4778 #if defined(TARGET_OS_TV) && TARGET_OS_TV == 1
4779     strm << "ostype:tvos;";
4780 #elif defined(TARGET_OS_WATCH) && TARGET_OS_WATCH == 1
4781     strm << "ostype:watchos;";
4782 #elif defined(TARGET_OS_BRIDGE) && TARGET_OS_BRIDGE == 1
4783     strm << "ostype:bridgeos;";
4784 #elif defined(TARGET_OS_OSX) && TARGET_OS_OSX == 1
4785     strm << "ostype:macosx;";
4786 #else
4787     strm << "ostype:ios;";
4788 #endif
4789 
4790     // On armv7 we use "synchronous" watchpoints which means the exception is
4791     // delivered before the instruction executes.
4792     strm << "watchpoint_exceptions_received:before;";
4793   } else {
4794     strm << "ostype:macosx;";
4795     strm << "watchpoint_exceptions_received:after;";
4796   }
4797   //    char ostype[64];
4798   //    len = sizeof(ostype);
4799   //    if (::sysctlbyname("kern.ostype", &ostype, &len, NULL, 0) == 0)
4800   //    {
4801   //        len = strlen(ostype);
4802   //        std::transform (ostype, ostype + len, ostype, tolower);
4803   //        strm << "ostype:" << std::dec << ostype << ';';
4804   //    }
4805 
4806   strm << "vendor:apple;";
4807 
4808   uint64_t major, minor, patch;
4809   if (DNBGetOSVersionNumbers(&major, &minor, &patch)) {
4810     strm << "os_version:" << major << "." << minor;
4811     if (patch != UINT64_MAX)
4812       strm << "." << patch;
4813     strm << ";";
4814   }
4815 
4816   std::string maccatalyst_version = DNBGetMacCatalystVersionString();
4817   if (!maccatalyst_version.empty() &&
4818       std::all_of(maccatalyst_version.begin(), maccatalyst_version.end(),
4819                   [](char c) { return (c >= '0' && c <= '9') || c == '.'; }))
4820     strm << "maccatalyst_version:" << maccatalyst_version << ";";
4821 
4822 #if defined(__LITTLE_ENDIAN__)
4823   strm << "endian:little;";
4824 #elif defined(__BIG_ENDIAN__)
4825   strm << "endian:big;";
4826 #elif defined(__PDP_ENDIAN__)
4827   strm << "endian:pdp;";
4828 #endif
4829 
4830   if (promoted_to_64)
4831     strm << "ptrsize:8;";
4832   else
4833     strm << "ptrsize:" << std::dec << sizeof(void *) << ';';
4834 
4835 #if defined(TARGET_OS_WATCH) && TARGET_OS_WATCH == 1
4836   strm << "default_packet_timeout:10;";
4837 #endif
4838 
4839   strm << "vm-page-size:" << std::dec << vm_page_size << ";";
4840 
4841   return SendPacket(strm.str());
4842 }
4843 
4844 void XMLElementStart(std::ostringstream &s, uint32_t indent, const char *name,
4845                      bool has_attributes) {
4846   if (indent)
4847     s << INDENT_WITH_SPACES(indent);
4848   s << '<' << name;
4849   if (!has_attributes)
4850     s << '>' << std::endl;
4851 }
4852 
4853 void XMLElementStartEndAttributes(std::ostringstream &s, bool empty) {
4854   if (empty)
4855     s << '/';
4856   s << '>' << std::endl;
4857 }
4858 
4859 void XMLElementEnd(std::ostringstream &s, uint32_t indent, const char *name) {
4860   if (indent)
4861     s << INDENT_WITH_SPACES(indent);
4862   s << '<' << '/' << name << '>' << std::endl;
4863 }
4864 
4865 void XMLElementWithStringValue(std::ostringstream &s, uint32_t indent,
4866                                const char *name, const char *value,
4867                                bool close = true) {
4868   if (value) {
4869     if (indent)
4870       s << INDENT_WITH_SPACES(indent);
4871     s << '<' << name << '>' << value;
4872     if (close)
4873       XMLElementEnd(s, 0, name);
4874   }
4875 }
4876 
4877 void XMLElementWithUnsignedValue(std::ostringstream &s, uint32_t indent,
4878                                  const char *name, uint64_t value,
4879                                  bool close = true) {
4880   if (indent)
4881     s << INDENT_WITH_SPACES(indent);
4882 
4883   s << '<' << name << '>' << DECIMAL << value;
4884   if (close)
4885     XMLElementEnd(s, 0, name);
4886 }
4887 
4888 void XMLAttributeString(std::ostringstream &s, const char *name,
4889                         const char *value, const char *default_value = NULL) {
4890   if (value) {
4891     if (default_value && strcmp(value, default_value) == 0)
4892       return; // No need to emit the attribute because it matches the default
4893               // value
4894     s << ' ' << name << "=\"" << value << "\"";
4895   }
4896 }
4897 
4898 void XMLAttributeUnsignedDecimal(std::ostringstream &s, const char *name,
4899                                  uint64_t value) {
4900   s << ' ' << name << "=\"" << DECIMAL << value << "\"";
4901 }
4902 
4903 void GenerateTargetXMLRegister(std::ostringstream &s, const uint32_t reg_num,
4904                                nub_size_t num_reg_sets,
4905                                const DNBRegisterSetInfo *reg_set_info,
4906                                const register_map_entry_t &reg) {
4907   const char *default_lldb_encoding = "uint";
4908   const char *lldb_encoding = default_lldb_encoding;
4909   const char *gdb_group = "general";
4910   const char *default_gdb_type = "int";
4911   const char *gdb_type = default_gdb_type;
4912   const char *default_lldb_format = "hex";
4913   const char *lldb_format = default_lldb_format;
4914   const char *lldb_set = NULL;
4915 
4916   switch (reg.nub_info.type) {
4917   case Uint:
4918     lldb_encoding = "uint";
4919     break;
4920   case Sint:
4921     lldb_encoding = "sint";
4922     break;
4923   case IEEE754:
4924     lldb_encoding = "ieee754";
4925     if (reg.nub_info.set > 0)
4926       gdb_group = "float";
4927     break;
4928   case Vector:
4929     lldb_encoding = "vector";
4930     if (reg.nub_info.set > 0)
4931       gdb_group = "vector";
4932     break;
4933   }
4934 
4935   switch (reg.nub_info.format) {
4936   case Binary:
4937     lldb_format = "binary";
4938     break;
4939   case Decimal:
4940     lldb_format = "decimal";
4941     break;
4942   case Hex:
4943     lldb_format = "hex";
4944     break;
4945   case Float:
4946     gdb_type = "float";
4947     lldb_format = "float";
4948     break;
4949   case VectorOfSInt8:
4950     gdb_type = "float";
4951     lldb_format = "vector-sint8";
4952     break;
4953   case VectorOfUInt8:
4954     gdb_type = "float";
4955     lldb_format = "vector-uint8";
4956     break;
4957   case VectorOfSInt16:
4958     gdb_type = "float";
4959     lldb_format = "vector-sint16";
4960     break;
4961   case VectorOfUInt16:
4962     gdb_type = "float";
4963     lldb_format = "vector-uint16";
4964     break;
4965   case VectorOfSInt32:
4966     gdb_type = "float";
4967     lldb_format = "vector-sint32";
4968     break;
4969   case VectorOfUInt32:
4970     gdb_type = "float";
4971     lldb_format = "vector-uint32";
4972     break;
4973   case VectorOfFloat32:
4974     gdb_type = "float";
4975     lldb_format = "vector-float32";
4976     break;
4977   case VectorOfUInt128:
4978     gdb_type = "float";
4979     lldb_format = "vector-uint128";
4980     break;
4981   };
4982   if (reg_set_info && reg.nub_info.set < num_reg_sets)
4983     lldb_set = reg_set_info[reg.nub_info.set].name;
4984 
4985   uint32_t indent = 2;
4986 
4987   XMLElementStart(s, indent, "reg", true);
4988   XMLAttributeString(s, "name", reg.nub_info.name);
4989   XMLAttributeUnsignedDecimal(s, "regnum", reg_num);
4990   XMLAttributeUnsignedDecimal(s, "offset", reg.offset);
4991   XMLAttributeUnsignedDecimal(s, "bitsize", reg.nub_info.size * 8);
4992   XMLAttributeString(s, "group", gdb_group);
4993   XMLAttributeString(s, "type", gdb_type, default_gdb_type);
4994   XMLAttributeString(s, "altname", reg.nub_info.alt);
4995   XMLAttributeString(s, "encoding", lldb_encoding, default_lldb_encoding);
4996   XMLAttributeString(s, "format", lldb_format, default_lldb_format);
4997   XMLAttributeUnsignedDecimal(s, "group_id", reg.nub_info.set);
4998   if (reg.nub_info.reg_ehframe != INVALID_NUB_REGNUM)
4999     XMLAttributeUnsignedDecimal(s, "ehframe_regnum", reg.nub_info.reg_ehframe);
5000   if (reg.nub_info.reg_dwarf != INVALID_NUB_REGNUM)
5001     XMLAttributeUnsignedDecimal(s, "dwarf_regnum", reg.nub_info.reg_dwarf);
5002 
5003   const char *lldb_generic = NULL;
5004   switch (reg.nub_info.reg_generic) {
5005   case GENERIC_REGNUM_FP:
5006     lldb_generic = "fp";
5007     break;
5008   case GENERIC_REGNUM_PC:
5009     lldb_generic = "pc";
5010     break;
5011   case GENERIC_REGNUM_SP:
5012     lldb_generic = "sp";
5013     break;
5014   case GENERIC_REGNUM_RA:
5015     lldb_generic = "ra";
5016     break;
5017   case GENERIC_REGNUM_FLAGS:
5018     lldb_generic = "flags";
5019     break;
5020   case GENERIC_REGNUM_ARG1:
5021     lldb_generic = "arg1";
5022     break;
5023   case GENERIC_REGNUM_ARG2:
5024     lldb_generic = "arg2";
5025     break;
5026   case GENERIC_REGNUM_ARG3:
5027     lldb_generic = "arg3";
5028     break;
5029   case GENERIC_REGNUM_ARG4:
5030     lldb_generic = "arg4";
5031     break;
5032   case GENERIC_REGNUM_ARG5:
5033     lldb_generic = "arg5";
5034     break;
5035   case GENERIC_REGNUM_ARG6:
5036     lldb_generic = "arg6";
5037     break;
5038   case GENERIC_REGNUM_ARG7:
5039     lldb_generic = "arg7";
5040     break;
5041   case GENERIC_REGNUM_ARG8:
5042     lldb_generic = "arg8";
5043     break;
5044   default:
5045     break;
5046   }
5047   XMLAttributeString(s, "generic", lldb_generic);
5048 
5049   bool empty = reg.value_regnums.empty() && reg.invalidate_regnums.empty();
5050   if (!empty) {
5051     if (!reg.value_regnums.empty()) {
5052       std::ostringstream regnums;
5053       bool first = true;
5054       regnums << DECIMAL;
5055       for (auto regnum : reg.value_regnums) {
5056         if (!first)
5057           regnums << ',';
5058         regnums << regnum;
5059         first = false;
5060       }
5061       XMLAttributeString(s, "value_regnums", regnums.str().c_str());
5062     }
5063 
5064     if (!reg.invalidate_regnums.empty()) {
5065       std::ostringstream regnums;
5066       bool first = true;
5067       regnums << DECIMAL;
5068       for (auto regnum : reg.invalidate_regnums) {
5069         if (!first)
5070           regnums << ',';
5071         regnums << regnum;
5072         first = false;
5073       }
5074       XMLAttributeString(s, "invalidate_regnums", regnums.str().c_str());
5075     }
5076   }
5077   XMLElementStartEndAttributes(s, true);
5078 }
5079 
5080 void GenerateTargetXMLRegisters(std::ostringstream &s) {
5081   nub_size_t num_reg_sets = 0;
5082   const DNBRegisterSetInfo *reg_sets = DNBGetRegisterSetInfo(&num_reg_sets);
5083 
5084   uint32_t cputype = DNBGetRegisterCPUType();
5085   if (cputype) {
5086     XMLElementStart(s, 0, "feature", true);
5087     std::ostringstream name_strm;
5088     name_strm << "com.apple.debugserver." << GetArchName(cputype, 0);
5089     XMLAttributeString(s, "name", name_strm.str().c_str());
5090     XMLElementStartEndAttributes(s, false);
5091     for (uint32_t reg_num = 0; reg_num < g_num_reg_entries; ++reg_num)
5092     //        for (const auto &reg: g_dynamic_register_map)
5093     {
5094       GenerateTargetXMLRegister(s, reg_num, num_reg_sets, reg_sets,
5095                                 g_reg_entries[reg_num]);
5096     }
5097     XMLElementEnd(s, 0, "feature");
5098 
5099     if (num_reg_sets > 0) {
5100       XMLElementStart(s, 0, "groups", false);
5101       for (uint32_t set = 1; set < num_reg_sets; ++set) {
5102         XMLElementStart(s, 2, "group", true);
5103         XMLAttributeUnsignedDecimal(s, "id", set);
5104         XMLAttributeString(s, "name", reg_sets[set].name);
5105         XMLElementStartEndAttributes(s, true);
5106       }
5107       XMLElementEnd(s, 0, "groups");
5108     }
5109   }
5110 }
5111 
5112 static const char *g_target_xml_header = R"(<?xml version="1.0"?>
5113 <target version="1.0">)";
5114 
5115 static const char *g_target_xml_footer = "</target>";
5116 
5117 static std::string g_target_xml;
5118 
5119 void UpdateTargetXML() {
5120   std::ostringstream s;
5121   s << g_target_xml_header << std::endl;
5122 
5123   // Set the architecture
5124   //
5125   // On raw targets (no OS, vendor info), I've seen replies like
5126   // <architecture>i386:x86-64</architecture> (for x86_64 systems - from vmware)
5127   // <architecture>arm</architecture> (for an unspecified arm device - from a Segger JLink)
5128   // For good interop, I'm not sure what's expected here.  e.g. will anyone understand
5129   // <architecture>x86_64</architecture> ? Or is i386:x86_64 the expected phrasing?
5130   //
5131   // s << "<architecture>" << arch "</architecture>" << std::endl;
5132 
5133   // Set the OSABI
5134   // s << "<osabi>abi-name</osabi>"
5135 
5136   GenerateTargetXMLRegisters(s);
5137 
5138   s << g_target_xml_footer << std::endl;
5139 
5140   // Save the XML output in case it gets retrieved in chunks
5141   g_target_xml = s.str();
5142 }
5143 
5144 rnb_err_t RNBRemote::HandlePacket_qXfer(const char *command) {
5145   const char *p = command;
5146   p += strlen("qXfer:");
5147   const char *sep = strchr(p, ':');
5148   if (sep) {
5149     std::string object(p, sep - p); // "auxv", "backtrace", "features", etc
5150     p = sep + 1;
5151     sep = strchr(p, ':');
5152     if (sep) {
5153       std::string rw(p, sep - p); // "read" or "write"
5154       p = sep + 1;
5155       sep = strchr(p, ':');
5156       if (sep) {
5157         std::string annex(p, sep - p); // "read" or "write"
5158 
5159         p = sep + 1;
5160         sep = strchr(p, ',');
5161         if (sep) {
5162           std::string offset_str(p, sep - p); // read the length as a string
5163           p = sep + 1;
5164           std::string length_str(p); // read the offset as a string
5165           char *end = nullptr;
5166           const uint64_t offset = strtoul(offset_str.c_str(), &end,
5167                                           16); // convert offset_str to a offset
5168           if (*end == '\0') {
5169             const uint64_t length = strtoul(
5170                 length_str.c_str(), &end, 16); // convert length_str to a length
5171             if (*end == '\0') {
5172               if (object == "features" && rw == "read" &&
5173                   annex == "target.xml") {
5174                 std::ostringstream xml_out;
5175 
5176                 if (offset == 0) {
5177                   InitializeRegisters(true);
5178 
5179                   UpdateTargetXML();
5180                   if (g_target_xml.empty())
5181                     return SendPacket("E83");
5182 
5183                   if (length > g_target_xml.size()) {
5184                     xml_out << 'l'; // No more data
5185                     xml_out << binary_encode_string(g_target_xml);
5186                   } else {
5187                     xml_out << 'm'; // More data needs to be read with a
5188                                     // subsequent call
5189                     xml_out << binary_encode_string(
5190                         std::string(g_target_xml, offset, length));
5191                   }
5192                 } else {
5193                   // Retrieving target XML in chunks
5194                   if (offset < g_target_xml.size()) {
5195                     std::string chunk(g_target_xml, offset, length);
5196                     if (chunk.size() < length)
5197                       xml_out << 'l'; // No more data
5198                     else
5199                       xml_out << 'm'; // More data needs to be read with a
5200                                       // subsequent call
5201                     xml_out << binary_encode_string(chunk.data());
5202                   }
5203                 }
5204                 return SendPacket(xml_out.str());
5205               }
5206               // Well formed, put not supported
5207               return HandlePacket_UNIMPLEMENTED(command);
5208             }
5209           }
5210         }
5211       } else {
5212         SendPacket("E85");
5213       }
5214     } else {
5215       SendPacket("E86");
5216     }
5217   }
5218   return SendPacket("E82");
5219 }
5220 
5221 rnb_err_t RNBRemote::HandlePacket_qGDBServerVersion(const char *p) {
5222   std::ostringstream strm;
5223 
5224 #if defined(DEBUGSERVER_PROGRAM_NAME)
5225   strm << "name:" DEBUGSERVER_PROGRAM_NAME ";";
5226 #else
5227   strm << "name:debugserver;";
5228 #endif
5229   strm << "version:" << DEBUGSERVER_VERSION_NUM << ";";
5230 
5231   return SendPacket(strm.str());
5232 }
5233 
5234 // A helper function that retrieves a single integer value from
5235 // a one-level-deep JSON dictionary of key-value pairs.  e.g.
5236 // jThreadExtendedInfo:{"plo_pthread_tsd_base_address_offset":0,"plo_pthread_tsd_base_offset":224,"plo_pthread_tsd_entry_size":8,"thread":144305}]
5237 //
5238 uint64_t get_integer_value_for_key_name_from_json(const char *key,
5239                                                   const char *json_string) {
5240   uint64_t retval = INVALID_NUB_ADDRESS;
5241   std::string key_with_quotes = "\"";
5242   key_with_quotes += key;
5243   key_with_quotes += "\"";
5244   const char *c = strstr(json_string, key_with_quotes.c_str());
5245   if (c) {
5246     c += key_with_quotes.size();
5247 
5248     while (*c != '\0' && (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5249       c++;
5250 
5251     if (*c == ':') {
5252       c++;
5253 
5254       while (*c != '\0' &&
5255              (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5256         c++;
5257 
5258       errno = 0;
5259       retval = strtoul(c, NULL, 10);
5260       if (errno != 0) {
5261         retval = INVALID_NUB_ADDRESS;
5262       }
5263     }
5264   }
5265   return retval;
5266 }
5267 
5268 // A helper function that retrieves a boolean value from
5269 // a one-level-deep JSON dictionary of key-value pairs.  e.g.
5270 // jGetLoadedDynamicLibrariesInfos:{"fetch_all_solibs":true}]
5271 
5272 // Returns true if it was able to find the key name, and sets the 'value'
5273 // argument to the value found.
5274 
5275 bool get_boolean_value_for_key_name_from_json(const char *key,
5276                                               const char *json_string,
5277                                               bool &value) {
5278   std::string key_with_quotes = "\"";
5279   key_with_quotes += key;
5280   key_with_quotes += "\"";
5281   const char *c = strstr(json_string, key_with_quotes.c_str());
5282   if (c) {
5283     c += key_with_quotes.size();
5284 
5285     while (*c != '\0' && (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5286       c++;
5287 
5288     if (*c == ':') {
5289       c++;
5290 
5291       while (*c != '\0' &&
5292              (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5293         c++;
5294 
5295       if (strncmp(c, "true", 4) == 0) {
5296         value = true;
5297         return true;
5298       } else if (strncmp(c, "false", 5) == 0) {
5299         value = false;
5300         return true;
5301       }
5302     }
5303   }
5304   return false;
5305 }
5306 
5307 // A helper function that reads an array of uint64_t's from
5308 // a one-level-deep JSON dictionary of key-value pairs.  e.g.
5309 // jGetLoadedDynamicLibrariesInfos:{"solib_addrs":[31345823,7768020384,7310483024]}]
5310 
5311 // Returns true if it was able to find the key name, false if it did not.
5312 // "ints" will have all integers found in the array appended to it.
5313 
5314 bool get_array_of_ints_value_for_key_name_from_json(
5315     const char *key, const char *json_string, std::vector<uint64_t> &ints) {
5316   std::string key_with_quotes = "\"";
5317   key_with_quotes += key;
5318   key_with_quotes += "\"";
5319   const char *c = strstr(json_string, key_with_quotes.c_str());
5320   if (c) {
5321     c += key_with_quotes.size();
5322 
5323     while (*c != '\0' && (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5324       c++;
5325 
5326     if (*c == ':') {
5327       c++;
5328 
5329       while (*c != '\0' &&
5330              (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5331         c++;
5332 
5333       if (*c == '[') {
5334         c++;
5335         while (*c != '\0' &&
5336                (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5337           c++;
5338         while (true) {
5339           if (!isdigit(*c)) {
5340             return true;
5341           }
5342 
5343           errno = 0;
5344           char *endptr;
5345           uint64_t value = strtoul(c, &endptr, 10);
5346           if (errno == 0) {
5347             ints.push_back(value);
5348           } else {
5349             break;
5350           }
5351           if (endptr == c || endptr == nullptr || *endptr == '\0') {
5352             break;
5353           }
5354           c = endptr;
5355 
5356           while (*c != '\0' &&
5357                  (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5358             c++;
5359           if (*c == ',')
5360             c++;
5361           while (*c != '\0' &&
5362                  (*c == ' ' || *c == '\t' || *c == '\n' || *c == '\r'))
5363             c++;
5364           if (*c == ']') {
5365             return true;
5366           }
5367         }
5368       }
5369     }
5370   }
5371   return false;
5372 }
5373 
5374 JSONGenerator::ObjectSP
5375 RNBRemote::GetJSONThreadsInfo(bool threads_with_valid_stop_info_only) {
5376   JSONGenerator::ArraySP threads_array_sp;
5377   if (m_ctx.HasValidProcessID()) {
5378     threads_array_sp = std::make_shared<JSONGenerator::Array>();
5379 
5380     nub_process_t pid = m_ctx.ProcessID();
5381 
5382     nub_size_t numthreads = DNBProcessGetNumThreads(pid);
5383     for (nub_size_t i = 0; i < numthreads; ++i) {
5384       nub_thread_t tid = DNBProcessGetThreadAtIndex(pid, i);
5385 
5386       struct DNBThreadStopInfo tid_stop_info;
5387 
5388       const bool stop_info_valid =
5389           DNBThreadGetStopReason(pid, tid, &tid_stop_info);
5390 
5391       // If we are doing stop info only, then we only show threads that have a
5392       // valid stop reason
5393       if (threads_with_valid_stop_info_only) {
5394         if (!stop_info_valid || tid_stop_info.reason == eStopTypeInvalid)
5395           continue;
5396       }
5397 
5398       JSONGenerator::DictionarySP thread_dict_sp(
5399           new JSONGenerator::Dictionary());
5400       thread_dict_sp->AddIntegerItem("tid", tid);
5401 
5402       std::string reason_value("none");
5403 
5404       if (stop_info_valid) {
5405         switch (tid_stop_info.reason) {
5406         case eStopTypeInvalid:
5407           break;
5408 
5409         case eStopTypeSignal:
5410           if (tid_stop_info.details.signal.signo != 0) {
5411             thread_dict_sp->AddIntegerItem("signal",
5412                                            tid_stop_info.details.signal.signo);
5413             reason_value = "signal";
5414           }
5415           break;
5416 
5417         case eStopTypeException:
5418           if (tid_stop_info.details.exception.type != 0) {
5419             reason_value = "exception";
5420             thread_dict_sp->AddIntegerItem(
5421                 "metype", tid_stop_info.details.exception.type);
5422             JSONGenerator::ArraySP medata_array_sp(new JSONGenerator::Array());
5423             for (nub_size_t i = 0;
5424                  i < tid_stop_info.details.exception.data_count; ++i) {
5425               medata_array_sp->AddItem(
5426                   JSONGenerator::IntegerSP(new JSONGenerator::Integer(
5427                       tid_stop_info.details.exception.data[i])));
5428             }
5429             thread_dict_sp->AddItem("medata", medata_array_sp);
5430           }
5431           break;
5432 
5433         case eStopTypeExec:
5434           reason_value = "exec";
5435           break;
5436         }
5437       }
5438 
5439       thread_dict_sp->AddStringItem("reason", reason_value);
5440 
5441       if (!threads_with_valid_stop_info_only) {
5442         const char *thread_name = DNBThreadGetName(pid, tid);
5443         if (thread_name && thread_name[0])
5444           thread_dict_sp->AddStringItem("name", thread_name);
5445 
5446         thread_identifier_info_data_t thread_ident_info;
5447         if (DNBThreadGetIdentifierInfo(pid, tid, &thread_ident_info)) {
5448           if (thread_ident_info.dispatch_qaddr != 0) {
5449             thread_dict_sp->AddIntegerItem("qaddr",
5450                                            thread_ident_info.dispatch_qaddr);
5451 
5452             const DispatchQueueOffsets *dispatch_queue_offsets =
5453                 GetDispatchQueueOffsets();
5454             if (dispatch_queue_offsets) {
5455               std::string queue_name;
5456               uint64_t queue_width = 0;
5457               uint64_t queue_serialnum = 0;
5458               nub_addr_t dispatch_queue_t = INVALID_NUB_ADDRESS;
5459               dispatch_queue_offsets->GetThreadQueueInfo(
5460                   pid, thread_ident_info.dispatch_qaddr, dispatch_queue_t,
5461                   queue_name, queue_width, queue_serialnum);
5462               if (dispatch_queue_t == 0 && queue_name.empty() &&
5463                   queue_serialnum == 0) {
5464                 thread_dict_sp->AddBooleanItem("associated_with_dispatch_queue",
5465                                                false);
5466               } else {
5467                 thread_dict_sp->AddBooleanItem("associated_with_dispatch_queue",
5468                                                true);
5469               }
5470               if (dispatch_queue_t != INVALID_NUB_ADDRESS &&
5471                   dispatch_queue_t != 0)
5472                 thread_dict_sp->AddIntegerItem("dispatch_queue_t",
5473                                                dispatch_queue_t);
5474               if (!queue_name.empty())
5475                 thread_dict_sp->AddStringItem("qname", queue_name);
5476               if (queue_width == 1)
5477                 thread_dict_sp->AddStringItem("qkind", "serial");
5478               else if (queue_width > 1)
5479                 thread_dict_sp->AddStringItem("qkind", "concurrent");
5480               if (queue_serialnum > 0)
5481                 thread_dict_sp->AddIntegerItem("qserialnum", queue_serialnum);
5482             }
5483           }
5484         }
5485 
5486         DNBRegisterValue reg_value;
5487 
5488         if (g_reg_entries != NULL) {
5489           JSONGenerator::DictionarySP registers_dict_sp(
5490               new JSONGenerator::Dictionary());
5491 
5492           for (uint32_t reg = 0; reg < g_num_reg_entries; reg++) {
5493             // Expedite all registers in the first register set that aren't
5494             // contained in other registers
5495             if (g_reg_entries[reg].nub_info.set == 1 &&
5496                 g_reg_entries[reg].nub_info.value_regs == NULL) {
5497               if (!DNBThreadGetRegisterValueByID(
5498                       pid, tid, g_reg_entries[reg].nub_info.set,
5499                       g_reg_entries[reg].nub_info.reg, &reg_value))
5500                 continue;
5501 
5502               std::ostringstream reg_num;
5503               reg_num << std::dec << g_reg_entries[reg].debugserver_regnum;
5504               // Encode native byte ordered bytes as hex ascii
5505               registers_dict_sp->AddBytesAsHexASCIIString(
5506                   reg_num.str(), reg_value.value.v_uint8,
5507                   g_reg_entries[reg].nub_info.size);
5508             }
5509           }
5510           thread_dict_sp->AddItem("registers", registers_dict_sp);
5511         }
5512 
5513         // Add expedited stack memory so stack backtracing doesn't need to read
5514         // anything from the
5515         // frame pointer chain.
5516         StackMemoryMap stack_mmap;
5517         ReadStackMemory(pid, tid, stack_mmap);
5518         if (!stack_mmap.empty()) {
5519           JSONGenerator::ArraySP memory_array_sp(new JSONGenerator::Array());
5520 
5521           for (const auto &stack_memory : stack_mmap) {
5522             JSONGenerator::DictionarySP stack_memory_sp(
5523                 new JSONGenerator::Dictionary());
5524             stack_memory_sp->AddIntegerItem("address", stack_memory.first);
5525             stack_memory_sp->AddBytesAsHexASCIIString(
5526                 "bytes", stack_memory.second.bytes, stack_memory.second.length);
5527             memory_array_sp->AddItem(stack_memory_sp);
5528           }
5529           thread_dict_sp->AddItem("memory", memory_array_sp);
5530         }
5531       }
5532 
5533       threads_array_sp->AddItem(thread_dict_sp);
5534     }
5535   }
5536   return threads_array_sp;
5537 }
5538 
5539 rnb_err_t RNBRemote::HandlePacket_jThreadsInfo(const char *p) {
5540   JSONGenerator::ObjectSP threads_info_sp;
5541   std::ostringstream json;
5542   std::ostringstream reply_strm;
5543   // If we haven't run the process yet, return an error.
5544   if (m_ctx.HasValidProcessID()) {
5545     const bool threads_with_valid_stop_info_only = false;
5546     JSONGenerator::ObjectSP threads_info_sp =
5547         GetJSONThreadsInfo(threads_with_valid_stop_info_only);
5548 
5549     if (threads_info_sp) {
5550       std::ostringstream strm;
5551       threads_info_sp->Dump(strm);
5552       std::string binary_packet = binary_encode_string(strm.str());
5553       if (!binary_packet.empty())
5554         return SendPacket(binary_packet.c_str());
5555     }
5556   }
5557   return SendPacket("E85");
5558 }
5559 
5560 rnb_err_t RNBRemote::HandlePacket_jThreadExtendedInfo(const char *p) {
5561   nub_process_t pid;
5562   std::ostringstream json;
5563   // If we haven't run the process yet, return an error.
5564   if (!m_ctx.HasValidProcessID()) {
5565     return SendPacket("E81");
5566   }
5567 
5568   pid = m_ctx.ProcessID();
5569 
5570   const char thread_extended_info_str[] = {"jThreadExtendedInfo:{"};
5571   if (strncmp(p, thread_extended_info_str,
5572               sizeof(thread_extended_info_str) - 1) == 0) {
5573     p += strlen(thread_extended_info_str);
5574 
5575     uint64_t tid = get_integer_value_for_key_name_from_json("thread", p);
5576     uint64_t plo_pthread_tsd_base_address_offset =
5577         get_integer_value_for_key_name_from_json(
5578             "plo_pthread_tsd_base_address_offset", p);
5579     uint64_t plo_pthread_tsd_base_offset =
5580         get_integer_value_for_key_name_from_json("plo_pthread_tsd_base_offset",
5581                                                  p);
5582     uint64_t plo_pthread_tsd_entry_size =
5583         get_integer_value_for_key_name_from_json("plo_pthread_tsd_entry_size",
5584                                                  p);
5585     uint64_t dti_qos_class_index =
5586         get_integer_value_for_key_name_from_json("dti_qos_class_index", p);
5587 
5588     if (tid != INVALID_NUB_ADDRESS) {
5589       nub_addr_t pthread_t_value = DNBGetPThreadT(pid, tid);
5590 
5591       uint64_t tsd_address = INVALID_NUB_ADDRESS;
5592       if (plo_pthread_tsd_entry_size != INVALID_NUB_ADDRESS &&
5593           plo_pthread_tsd_base_offset != INVALID_NUB_ADDRESS &&
5594           plo_pthread_tsd_entry_size != INVALID_NUB_ADDRESS) {
5595         tsd_address = DNBGetTSDAddressForThread(
5596             pid, tid, plo_pthread_tsd_base_address_offset,
5597             plo_pthread_tsd_base_offset, plo_pthread_tsd_entry_size);
5598       }
5599 
5600       bool timed_out = false;
5601       Genealogy::ThreadActivitySP thread_activity_sp;
5602 
5603       // If the pthread_t value is invalid, or if we were able to fetch the
5604       // thread's TSD base
5605       // and got an invalid value back, then we have a thread in early startup
5606       // or shutdown and
5607       // it's possible that gathering the genealogy information for this thread
5608       // go badly.
5609       // Ideally fetching this info for a thread in these odd states shouldn't
5610       // matter - but
5611       // we've seen some problems with these new SPI and threads in edge-casey
5612       // states.
5613 
5614       double genealogy_fetch_time = 0;
5615       if (pthread_t_value != INVALID_NUB_ADDRESS &&
5616           tsd_address != INVALID_NUB_ADDRESS) {
5617         DNBTimer timer(false);
5618         thread_activity_sp = DNBGetGenealogyInfoForThread(pid, tid, timed_out);
5619         genealogy_fetch_time = timer.ElapsedMicroSeconds(false) / 1000000.0;
5620       }
5621 
5622       std::unordered_set<uint32_t>
5623           process_info_indexes; // an array of the process info #'s seen
5624 
5625       json << "{";
5626 
5627       bool need_to_print_comma = false;
5628 
5629       if (thread_activity_sp && !timed_out) {
5630         const Genealogy::Activity *activity =
5631             &thread_activity_sp->current_activity;
5632         bool need_vouchers_comma_sep = false;
5633         json << "\"activity_query_timed_out\":false,";
5634         if (genealogy_fetch_time != 0) {
5635           //  If we append the floating point value with << we'll get it in
5636           //  scientific
5637           //  notation.
5638           char floating_point_ascii_buffer[64];
5639           floating_point_ascii_buffer[0] = '\0';
5640           snprintf(floating_point_ascii_buffer,
5641                    sizeof(floating_point_ascii_buffer), "%f",
5642                    genealogy_fetch_time);
5643           if (strlen(floating_point_ascii_buffer) > 0) {
5644             if (need_to_print_comma)
5645               json << ",";
5646             need_to_print_comma = true;
5647             json << "\"activity_query_duration\":"
5648                  << floating_point_ascii_buffer;
5649           }
5650         }
5651         if (activity->activity_id != 0) {
5652           if (need_to_print_comma)
5653             json << ",";
5654           need_to_print_comma = true;
5655           need_vouchers_comma_sep = true;
5656           json << "\"activity\":{";
5657           json << "\"start\":" << activity->activity_start << ",";
5658           json << "\"id\":" << activity->activity_id << ",";
5659           json << "\"parent_id\":" << activity->parent_id << ",";
5660           json << "\"name\":\""
5661                << json_string_quote_metachars(activity->activity_name) << "\",";
5662           json << "\"reason\":\""
5663                << json_string_quote_metachars(activity->reason) << "\"";
5664           json << "}";
5665         }
5666         if (thread_activity_sp->messages.size() > 0) {
5667           need_to_print_comma = true;
5668           if (need_vouchers_comma_sep)
5669             json << ",";
5670           need_vouchers_comma_sep = true;
5671           json << "\"trace_messages\":[";
5672           bool printed_one_message = false;
5673           for (auto iter = thread_activity_sp->messages.begin();
5674                iter != thread_activity_sp->messages.end(); ++iter) {
5675             if (printed_one_message)
5676               json << ",";
5677             else
5678               printed_one_message = true;
5679             json << "{";
5680             json << "\"timestamp\":" << iter->timestamp << ",";
5681             json << "\"activity_id\":" << iter->activity_id << ",";
5682             json << "\"trace_id\":" << iter->trace_id << ",";
5683             json << "\"thread\":" << iter->thread << ",";
5684             json << "\"type\":" << (int)iter->type << ",";
5685             json << "\"process_info_index\":" << iter->process_info_index
5686                  << ",";
5687             process_info_indexes.insert(iter->process_info_index);
5688             json << "\"message\":\""
5689                  << json_string_quote_metachars(iter->message) << "\"";
5690             json << "}";
5691           }
5692           json << "]";
5693         }
5694         if (thread_activity_sp->breadcrumbs.size() == 1) {
5695           need_to_print_comma = true;
5696           if (need_vouchers_comma_sep)
5697             json << ",";
5698           need_vouchers_comma_sep = true;
5699           json << "\"breadcrumb\":{";
5700           for (auto iter = thread_activity_sp->breadcrumbs.begin();
5701                iter != thread_activity_sp->breadcrumbs.end(); ++iter) {
5702             json << "\"breadcrumb_id\":" << iter->breadcrumb_id << ",";
5703             json << "\"activity_id\":" << iter->activity_id << ",";
5704             json << "\"timestamp\":" << iter->timestamp << ",";
5705             json << "\"name\":\"" << json_string_quote_metachars(iter->name)
5706                  << "\"";
5707           }
5708           json << "}";
5709         }
5710         if (process_info_indexes.size() > 0) {
5711           need_to_print_comma = true;
5712           if (need_vouchers_comma_sep)
5713             json << ",";
5714           need_vouchers_comma_sep = true;
5715           bool printed_one_process_info = false;
5716           for (auto iter = process_info_indexes.begin();
5717                iter != process_info_indexes.end(); ++iter) {
5718             if (printed_one_process_info)
5719               json << ",";
5720             Genealogy::ProcessExecutableInfoSP image_info_sp;
5721             uint32_t idx = *iter;
5722             image_info_sp = DNBGetGenealogyImageInfo(pid, idx);
5723             if (image_info_sp) {
5724               if (!printed_one_process_info) {
5725                 json << "\"process_infos\":[";
5726                 printed_one_process_info = true;
5727               }
5728 
5729               json << "{";
5730               char uuid_buf[37];
5731               uuid_unparse_upper(image_info_sp->image_uuid, uuid_buf);
5732               json << "\"process_info_index\":" << idx << ",";
5733               json << "\"image_path\":\""
5734                    << json_string_quote_metachars(image_info_sp->image_path)
5735                    << "\",";
5736               json << "\"image_uuid\":\"" << uuid_buf << "\"";
5737               json << "}";
5738             }
5739           }
5740           if (printed_one_process_info)
5741             json << "]";
5742         }
5743       } else {
5744         if (timed_out) {
5745           if (need_to_print_comma)
5746             json << ",";
5747           need_to_print_comma = true;
5748           json << "\"activity_query_timed_out\":true";
5749           if (genealogy_fetch_time != 0) {
5750             //  If we append the floating point value with << we'll get it in
5751             //  scientific
5752             //  notation.
5753             char floating_point_ascii_buffer[64];
5754             floating_point_ascii_buffer[0] = '\0';
5755             snprintf(floating_point_ascii_buffer,
5756                      sizeof(floating_point_ascii_buffer), "%f",
5757                      genealogy_fetch_time);
5758             if (strlen(floating_point_ascii_buffer) > 0) {
5759               json << ",";
5760               json << "\"activity_query_duration\":"
5761                    << floating_point_ascii_buffer;
5762             }
5763           }
5764         }
5765       }
5766 
5767       if (tsd_address != INVALID_NUB_ADDRESS) {
5768         if (need_to_print_comma)
5769           json << ",";
5770         need_to_print_comma = true;
5771         json << "\"tsd_address\":" << tsd_address;
5772 
5773         if (dti_qos_class_index != 0 && dti_qos_class_index != UINT64_MAX) {
5774           ThreadInfo::QoS requested_qos = DNBGetRequestedQoSForThread(
5775               pid, tid, tsd_address, dti_qos_class_index);
5776           if (requested_qos.IsValid()) {
5777             if (need_to_print_comma)
5778               json << ",";
5779             need_to_print_comma = true;
5780             json << "\"requested_qos\":{";
5781             json << "\"enum_value\":" << requested_qos.enum_value << ",";
5782             json << "\"constant_name\":\""
5783                  << json_string_quote_metachars(requested_qos.constant_name)
5784                  << "\",";
5785             json << "\"printable_name\":\""
5786                  << json_string_quote_metachars(requested_qos.printable_name)
5787                  << "\"";
5788             json << "}";
5789           }
5790         }
5791       }
5792 
5793       if (pthread_t_value != INVALID_NUB_ADDRESS) {
5794         if (need_to_print_comma)
5795           json << ",";
5796         need_to_print_comma = true;
5797         json << "\"pthread_t\":" << pthread_t_value;
5798       }
5799 
5800       nub_addr_t dispatch_queue_t_value = DNBGetDispatchQueueT(pid, tid);
5801       if (dispatch_queue_t_value != INVALID_NUB_ADDRESS) {
5802         if (need_to_print_comma)
5803           json << ",";
5804         need_to_print_comma = true;
5805         json << "\"dispatch_queue_t\":" << dispatch_queue_t_value;
5806       }
5807 
5808       json << "}";
5809       std::string json_quoted = binary_encode_string(json.str());
5810       return SendPacket(json_quoted);
5811     }
5812   }
5813   return SendPacket("OK");
5814 }
5815 
5816 //  This packet may be called in one of three ways:
5817 //
5818 //  jGetLoadedDynamicLibrariesInfos:{"image_count":40,"image_list_address":4295244704}
5819 //      Look for an array of the old dyld_all_image_infos style of binary infos
5820 //      at the image_list_address.
5821 //      This an array of {void* load_addr, void* mod_date, void* pathname}
5822 //
5823 //  jGetLoadedDynamicLibrariesInfos:{"fetch_all_solibs":true}
5824 //      Use the new style (macOS 10.12, tvOS 10, iOS 10, watchOS 3) dyld SPI to
5825 //      get a list of all the
5826 //      libraries loaded
5827 //
5828 //  jGetLoadedDynamicLibrariesInfos:{"solib_addresses":[8382824135,3258302053,830202858503]}
5829 //      Use the new style (macOS 10.12, tvOS 10, iOS 10, watchOS 3) dyld SPI to
5830 //      get the information
5831 //      about the libraries loaded at these addresses.
5832 //
5833 rnb_err_t
5834 RNBRemote::HandlePacket_jGetLoadedDynamicLibrariesInfos(const char *p) {
5835   nub_process_t pid;
5836   // If we haven't run the process yet, return an error.
5837   if (!m_ctx.HasValidProcessID()) {
5838     return SendPacket("E83");
5839   }
5840 
5841   pid = m_ctx.ProcessID();
5842 
5843   const char get_loaded_dynamic_libraries_infos_str[] = {
5844       "jGetLoadedDynamicLibrariesInfos:{"};
5845   if (strncmp(p, get_loaded_dynamic_libraries_infos_str,
5846               sizeof(get_loaded_dynamic_libraries_infos_str) - 1) == 0) {
5847     p += strlen(get_loaded_dynamic_libraries_infos_str);
5848 
5849     JSONGenerator::ObjectSP json_sp;
5850 
5851     std::vector<uint64_t> macho_addresses;
5852     bool fetch_all_solibs = false;
5853     if (get_boolean_value_for_key_name_from_json("fetch_all_solibs", p,
5854                                                  fetch_all_solibs) &&
5855         fetch_all_solibs) {
5856       json_sp = DNBGetAllLoadedLibrariesInfos(pid);
5857     } else if (get_array_of_ints_value_for_key_name_from_json(
5858                    "solib_addresses", p, macho_addresses)) {
5859       json_sp = DNBGetLibrariesInfoForAddresses(pid, macho_addresses);
5860     } else {
5861       nub_addr_t image_list_address =
5862           get_integer_value_for_key_name_from_json("image_list_address", p);
5863       nub_addr_t image_count =
5864           get_integer_value_for_key_name_from_json("image_count", p);
5865 
5866       if (image_list_address != INVALID_NUB_ADDRESS &&
5867           image_count != INVALID_NUB_ADDRESS) {
5868         json_sp = DNBGetLoadedDynamicLibrariesInfos(pid, image_list_address,
5869                                                     image_count);
5870       }
5871     }
5872 
5873     if (json_sp.get()) {
5874       std::ostringstream json_str;
5875       json_sp->Dump(json_str);
5876       if (json_str.str().size() > 0) {
5877         std::string json_str_quoted = binary_encode_string(json_str.str());
5878         return SendPacket(json_str_quoted.c_str());
5879       } else {
5880         SendPacket("E84");
5881       }
5882     }
5883   }
5884   return SendPacket("OK");
5885 }
5886 
5887 // This packet does not currently take any arguments.  So the behavior is
5888 //    jGetSharedCacheInfo:{}
5889 //         send information about the inferior's shared cache
5890 //    jGetSharedCacheInfo:
5891 //         send "OK" to indicate that this packet is supported
5892 rnb_err_t RNBRemote::HandlePacket_jGetSharedCacheInfo(const char *p) {
5893   nub_process_t pid;
5894   // If we haven't run the process yet, return an error.
5895   if (!m_ctx.HasValidProcessID()) {
5896     return SendPacket("E85");
5897   }
5898 
5899   pid = m_ctx.ProcessID();
5900 
5901   const char get_shared_cache_info_str[] = {"jGetSharedCacheInfo:{"};
5902   if (strncmp(p, get_shared_cache_info_str,
5903               sizeof(get_shared_cache_info_str) - 1) == 0) {
5904     JSONGenerator::ObjectSP json_sp = DNBGetSharedCacheInfo(pid);
5905 
5906     if (json_sp.get()) {
5907       std::ostringstream json_str;
5908       json_sp->Dump(json_str);
5909       if (json_str.str().size() > 0) {
5910         std::string json_str_quoted = binary_encode_string(json_str.str());
5911         return SendPacket(json_str_quoted.c_str());
5912       } else {
5913         SendPacket("E86");
5914       }
5915     }
5916   }
5917   return SendPacket("OK");
5918 }
5919 
5920 static bool MachHeaderIsMainExecutable(nub_process_t pid, uint32_t addr_size,
5921                                        nub_addr_t mach_header_addr,
5922                                        mach_header &mh) {
5923   DNBLogThreadedIf(LOG_RNB_PROC, "GetMachHeaderForMainExecutable(pid = %u, "
5924                                  "addr_size = %u, mach_header_addr = "
5925                                  "0x%16.16llx)",
5926                    pid, addr_size, mach_header_addr);
5927   const nub_size_t bytes_read =
5928       DNBProcessMemoryRead(pid, mach_header_addr, sizeof(mh), &mh);
5929   if (bytes_read == sizeof(mh)) {
5930     DNBLogThreadedIf(
5931         LOG_RNB_PROC, "GetMachHeaderForMainExecutable(pid = %u, addr_size = "
5932                       "%u, mach_header_addr = 0x%16.16llx): mh = {\n  magic = "
5933                       "0x%8.8x\n  cpu = 0x%8.8x\n  sub = 0x%8.8x\n  filetype = "
5934                       "%u\n  ncmds = %u\n  sizeofcmds = 0x%8.8x\n  flags = "
5935                       "0x%8.8x }",
5936         pid, addr_size, mach_header_addr, mh.magic, mh.cputype, mh.cpusubtype,
5937         mh.filetype, mh.ncmds, mh.sizeofcmds, mh.flags);
5938     if ((addr_size == 4 && mh.magic == MH_MAGIC) ||
5939         (addr_size == 8 && mh.magic == MH_MAGIC_64)) {
5940       if (mh.filetype == MH_EXECUTE) {
5941         DNBLogThreadedIf(LOG_RNB_PROC, "GetMachHeaderForMainExecutable(pid = "
5942                                        "%u, addr_size = %u, mach_header_addr = "
5943                                        "0x%16.16llx) -> this is the "
5944                                        "executable!!!",
5945                          pid, addr_size, mach_header_addr);
5946         return true;
5947       }
5948     }
5949   }
5950   return false;
5951 }
5952 
5953 static nub_addr_t GetMachHeaderForMainExecutable(const nub_process_t pid,
5954                                                  const uint32_t addr_size,
5955                                                  mach_header &mh) {
5956   struct AllImageInfos {
5957     uint32_t version;
5958     uint32_t dylib_info_count;
5959     uint64_t dylib_info_addr;
5960   };
5961 
5962   uint64_t mach_header_addr = 0;
5963 
5964   const nub_addr_t shlib_addr = DNBProcessGetSharedLibraryInfoAddress(pid);
5965   uint8_t bytes[256];
5966   nub_size_t bytes_read = 0;
5967   DNBDataRef data(bytes, sizeof(bytes), false);
5968   DNBDataRef::offset_t offset = 0;
5969   data.SetPointerSize(addr_size);
5970 
5971   // When we are sitting at __dyld_start, the kernel has placed the
5972   // address of the mach header of the main executable on the stack. If we
5973   // read the SP and dereference a pointer, we might find the mach header
5974   // for the executable. We also just make sure there is only 1 thread
5975   // since if we are at __dyld_start we shouldn't have multiple threads.
5976   if (DNBProcessGetNumThreads(pid) == 1) {
5977     nub_thread_t tid = DNBProcessGetThreadAtIndex(pid, 0);
5978     if (tid != INVALID_NUB_THREAD) {
5979       DNBRegisterValue sp_value;
5980       if (DNBThreadGetRegisterValueByID(pid, tid, REGISTER_SET_GENERIC,
5981                                         GENERIC_REGNUM_SP, &sp_value)) {
5982         uint64_t sp =
5983             addr_size == 8 ? sp_value.value.uint64 : sp_value.value.uint32;
5984         bytes_read = DNBProcessMemoryRead(pid, sp, addr_size, bytes);
5985         if (bytes_read == addr_size) {
5986           offset = 0;
5987           mach_header_addr = data.GetPointer(&offset);
5988           if (MachHeaderIsMainExecutable(pid, addr_size, mach_header_addr, mh))
5989             return mach_header_addr;
5990         }
5991       }
5992     }
5993   }
5994 
5995   // Check the dyld_all_image_info structure for a list of mach header
5996   // since it is a very easy thing to check
5997   if (shlib_addr != INVALID_NUB_ADDRESS) {
5998     bytes_read =
5999         DNBProcessMemoryRead(pid, shlib_addr, sizeof(AllImageInfos), bytes);
6000     if (bytes_read > 0) {
6001       AllImageInfos aii;
6002       offset = 0;
6003       aii.version = data.Get32(&offset);
6004       aii.dylib_info_count = data.Get32(&offset);
6005       if (aii.dylib_info_count > 0) {
6006         aii.dylib_info_addr = data.GetPointer(&offset);
6007         if (aii.dylib_info_addr != 0) {
6008           const size_t image_info_byte_size = 3 * addr_size;
6009           for (uint32_t i = 0; i < aii.dylib_info_count; ++i) {
6010             bytes_read = DNBProcessMemoryRead(pid, aii.dylib_info_addr +
6011                                                        i * image_info_byte_size,
6012                                               image_info_byte_size, bytes);
6013             if (bytes_read != image_info_byte_size)
6014               break;
6015             offset = 0;
6016             mach_header_addr = data.GetPointer(&offset);
6017             if (MachHeaderIsMainExecutable(pid, addr_size, mach_header_addr,
6018                                            mh))
6019               return mach_header_addr;
6020           }
6021         }
6022       }
6023     }
6024   }
6025 
6026   // We failed to find the executable's mach header from the all image
6027   // infos and by dereferencing the stack pointer. Now we fall back to
6028   // enumerating the memory regions and looking for regions that are
6029   // executable.
6030   DNBRegionInfo region_info;
6031   mach_header_addr = 0;
6032   while (DNBProcessMemoryRegionInfo(pid, mach_header_addr, &region_info)) {
6033     if (region_info.size == 0)
6034       break;
6035 
6036     if (region_info.permissions & eMemoryPermissionsExecutable) {
6037       DNBLogThreadedIf(
6038           LOG_RNB_PROC, "[0x%16.16llx - 0x%16.16llx) permissions = %c%c%c: "
6039                         "checking region for executable mach header",
6040           region_info.addr, region_info.addr + region_info.size,
6041           (region_info.permissions & eMemoryPermissionsReadable) ? 'r' : '-',
6042           (region_info.permissions & eMemoryPermissionsWritable) ? 'w' : '-',
6043           (region_info.permissions & eMemoryPermissionsExecutable) ? 'x' : '-');
6044       if (MachHeaderIsMainExecutable(pid, addr_size, mach_header_addr, mh))
6045         return mach_header_addr;
6046     } else {
6047       DNBLogThreadedIf(
6048           LOG_RNB_PROC,
6049           "[0x%16.16llx - 0x%16.16llx): permissions = %c%c%c: skipping region",
6050           region_info.addr, region_info.addr + region_info.size,
6051           (region_info.permissions & eMemoryPermissionsReadable) ? 'r' : '-',
6052           (region_info.permissions & eMemoryPermissionsWritable) ? 'w' : '-',
6053           (region_info.permissions & eMemoryPermissionsExecutable) ? 'x' : '-');
6054     }
6055     // Set the address to the next mapped region
6056     mach_header_addr = region_info.addr + region_info.size;
6057   }
6058   bzero(&mh, sizeof(mh));
6059   return INVALID_NUB_ADDRESS;
6060 }
6061 
6062 rnb_err_t RNBRemote::HandlePacket_qSymbol(const char *command) {
6063   const char *p = command;
6064   p += strlen("qSymbol:");
6065   const char *sep = strchr(p, ':');
6066 
6067   std::string symbol_name;
6068   std::string symbol_value_str;
6069   // Extract the symbol value if there is one
6070   if (sep > p)
6071     symbol_value_str.assign(p, sep - p);
6072   p = sep + 1;
6073 
6074   if (*p) {
6075     // We have a symbol name
6076     symbol_name = decode_hex_ascii_string(p);
6077     if (!symbol_value_str.empty()) {
6078       nub_addr_t symbol_value = decode_uint64(symbol_value_str.c_str(), 16);
6079       if (symbol_name == "dispatch_queue_offsets")
6080         m_dispatch_queue_offsets_addr = symbol_value;
6081     }
6082     ++m_qSymbol_index;
6083   } else {
6084     // No symbol name, set our symbol index to zero so we can
6085     // read any symbols that we need
6086     m_qSymbol_index = 0;
6087   }
6088 
6089   symbol_name.clear();
6090 
6091   if (m_qSymbol_index == 0) {
6092     if (m_dispatch_queue_offsets_addr == INVALID_NUB_ADDRESS)
6093       symbol_name = "dispatch_queue_offsets";
6094     else
6095       ++m_qSymbol_index;
6096   }
6097 
6098   //    // Lookup next symbol when we have one...
6099   //    if (m_qSymbol_index == 1)
6100   //    {
6101   //    }
6102 
6103   if (symbol_name.empty()) {
6104     // Done with symbol lookups
6105     return SendPacket("OK");
6106   } else {
6107     std::ostringstream reply;
6108     reply << "qSymbol:";
6109     for (size_t i = 0; i < symbol_name.size(); ++i)
6110       reply << RAWHEX8(symbol_name[i]);
6111     return SendPacket(reply.str().c_str());
6112   }
6113 }
6114 
6115 // Note that all numeric values returned by qProcessInfo are hex encoded,
6116 // including the pid and the cpu type.
6117 
6118 rnb_err_t RNBRemote::HandlePacket_qProcessInfo(const char *p) {
6119   nub_process_t pid;
6120   std::ostringstream rep;
6121 
6122   // If we haven't run the process yet, return an error.
6123   if (!m_ctx.HasValidProcessID())
6124     return SendPacket("E68");
6125 
6126   pid = m_ctx.ProcessID();
6127 
6128   rep << "pid:" << std::hex << pid << ';';
6129 
6130   int procpid_mib[4];
6131   procpid_mib[0] = CTL_KERN;
6132   procpid_mib[1] = KERN_PROC;
6133   procpid_mib[2] = KERN_PROC_PID;
6134   procpid_mib[3] = pid;
6135   struct kinfo_proc proc_kinfo;
6136   size_t proc_kinfo_size = sizeof(struct kinfo_proc);
6137 
6138   if (::sysctl(procpid_mib, 4, &proc_kinfo, &proc_kinfo_size, NULL, 0) == 0) {
6139     if (proc_kinfo_size > 0) {
6140       rep << "parent-pid:" << std::hex << proc_kinfo.kp_eproc.e_ppid << ';';
6141       rep << "real-uid:" << std::hex << proc_kinfo.kp_eproc.e_pcred.p_ruid
6142           << ';';
6143       rep << "real-gid:" << std::hex << proc_kinfo.kp_eproc.e_pcred.p_rgid
6144           << ';';
6145       rep << "effective-uid:" << std::hex << proc_kinfo.kp_eproc.e_ucred.cr_uid
6146           << ';';
6147       if (proc_kinfo.kp_eproc.e_ucred.cr_ngroups > 0)
6148         rep << "effective-gid:" << std::hex
6149             << proc_kinfo.kp_eproc.e_ucred.cr_groups[0] << ';';
6150     }
6151   }
6152 
6153   cpu_type_t cputype = DNBProcessGetCPUType(pid);
6154   if (cputype == 0) {
6155     DNBLog("Unable to get the process cpu_type, making a best guess.");
6156     cputype = best_guess_cpu_type();
6157   }
6158 
6159   uint32_t addr_size = 0;
6160   if (cputype != 0) {
6161     rep << "cputype:" << std::hex << cputype << ";";
6162     if (cputype & CPU_ARCH_ABI64)
6163       addr_size = 8;
6164     else
6165       addr_size = 4;
6166   }
6167 
6168   bool host_cpu_is_64bit = false;
6169   uint32_t is64bit_capable;
6170   size_t is64bit_capable_len = sizeof(is64bit_capable);
6171   if (sysctlbyname("hw.cpu64bit_capable", &is64bit_capable,
6172                    &is64bit_capable_len, NULL, 0) == 0)
6173     host_cpu_is_64bit = is64bit_capable != 0;
6174 
6175   uint32_t cpusubtype;
6176   size_t cpusubtype_len = sizeof(cpusubtype);
6177   if (::sysctlbyname("hw.cpusubtype", &cpusubtype, &cpusubtype_len, NULL, 0) ==
6178       0) {
6179     // If a process is CPU_TYPE_X86, then ignore the cpusubtype that we detected
6180     // from the host and use CPU_SUBTYPE_I386_ALL because we don't want the
6181     // CPU_SUBTYPE_X86_ARCH1 or CPU_SUBTYPE_X86_64_H to be used as the cpu
6182     // subtype
6183     // for i386...
6184     if (host_cpu_is_64bit) {
6185       if (cputype == CPU_TYPE_X86) {
6186         cpusubtype = 3; // CPU_SUBTYPE_I386_ALL
6187       } else if (cputype == CPU_TYPE_ARM) {
6188         // We can query a process' cputype but we cannot query a process'
6189         // cpusubtype.
6190         // If the process has cputype CPU_TYPE_ARM, then it is an armv7 (32-bit
6191         // process) and we
6192         // need to override the host cpusubtype (which is in the
6193         // CPU_SUBTYPE_ARM64 subtype namespace)
6194         // with a reasonable CPU_SUBTYPE_ARMV7 subtype.
6195         cpusubtype = 12; // CPU_SUBTYPE_ARM_V7K
6196       }
6197     }
6198 #if defined (TARGET_OS_WATCH) && TARGET_OS_WATCH == 1
6199     // on arm64_32 devices, the machine's native cpu type is
6200     // CPU_TYPE_ARM64 and subtype is 2 indicating arm64e.
6201     // But we change the cputype to CPU_TYPE_ARM64_32 because
6202     // the user processes are all ILP32 processes today.
6203     // We also need to rewrite the cpusubtype so we vend
6204     // a valid cputype + cpusubtype combination.
6205     if (cputype == CPU_TYPE_ARM64_32 && cpusubtype == 2)
6206       cpusubtype = CPU_SUBTYPE_ARM64_32_V8;
6207 #endif
6208 
6209     rep << "cpusubtype:" << std::hex << cpusubtype << ';';
6210   }
6211 
6212   bool os_handled = false;
6213   if (addr_size > 0) {
6214     rep << "ptrsize:" << std::dec << addr_size << ';';
6215 
6216 #if defined(TARGET_OS_OSX) && TARGET_OS_OSX == 1
6217     // Try and get the OS type by looking at the load commands in the main
6218     // executable and looking for a LC_VERSION_MIN load command. This is the
6219     // most reliable way to determine the "ostype" value when on desktop.
6220 
6221     mach_header mh;
6222     nub_addr_t exe_mach_header_addr =
6223         GetMachHeaderForMainExecutable(pid, addr_size, mh);
6224     if (exe_mach_header_addr != INVALID_NUB_ADDRESS) {
6225       uint64_t load_command_addr =
6226           exe_mach_header_addr +
6227           ((addr_size == 8) ? sizeof(mach_header_64) : sizeof(mach_header));
6228       load_command lc;
6229       for (uint32_t i = 0; i < mh.ncmds && !os_handled; ++i) {
6230         const nub_size_t bytes_read =
6231             DNBProcessMemoryRead(pid, load_command_addr, sizeof(lc), &lc);
6232         (void)bytes_read;
6233 
6234         bool is_executable = true;
6235         uint32_t major_version, minor_version, patch_version;
6236         auto *platform =
6237             DNBGetDeploymentInfo(pid, is_executable, lc, load_command_addr,
6238                                  major_version, minor_version, patch_version);
6239         if (platform) {
6240           os_handled = true;
6241           rep << "ostype:" << platform << ";";
6242           break;
6243         }
6244         load_command_addr = load_command_addr + lc.cmdsize;
6245       }
6246     }
6247 #endif // TARGET_OS_OSX
6248   }
6249 
6250   // If we weren't able to find the OS in a LC_VERSION_MIN load command, try
6251   // to set it correctly by using the cpu type and other tricks
6252   if (!os_handled) {
6253     // The OS in the triple should be "ios" or "macosx" which doesn't match our
6254     // "Darwin" which gets returned from "kern.ostype", so we need to hardcode
6255     // this for now.
6256     if (cputype == CPU_TYPE_ARM || cputype == CPU_TYPE_ARM64
6257         || cputype == CPU_TYPE_ARM64_32) {
6258 #if defined(TARGET_OS_TV) && TARGET_OS_TV == 1
6259       rep << "ostype:tvos;";
6260 #elif defined(TARGET_OS_WATCH) && TARGET_OS_WATCH == 1
6261       rep << "ostype:watchos;";
6262 #elif defined(TARGET_OS_BRIDGE) && TARGET_OS_BRIDGE == 1
6263       rep << "ostype:bridgeos;";
6264 #elif defined(TARGET_OS_OSX) && TARGET_OS_OSX == 1
6265       rep << "ostype:macosx;";
6266 #else
6267       rep << "ostype:ios;";
6268 #endif
6269     } else {
6270       bool is_ios_simulator = false;
6271       if (cputype == CPU_TYPE_X86 || cputype == CPU_TYPE_X86_64) {
6272         // Check for iOS simulator binaries by getting the process argument
6273         // and environment and checking for SIMULATOR_UDID in the environment
6274         int proc_args_mib[3] = {CTL_KERN, KERN_PROCARGS2, (int)pid};
6275 
6276         uint8_t arg_data[8192];
6277         size_t arg_data_size = sizeof(arg_data);
6278         if (::sysctl(proc_args_mib, 3, arg_data, &arg_data_size, NULL, 0) ==
6279             0) {
6280           DNBDataRef data(arg_data, arg_data_size, false);
6281           DNBDataRef::offset_t offset = 0;
6282           uint32_t argc = data.Get32(&offset);
6283           const char *cstr;
6284 
6285           cstr = data.GetCStr(&offset);
6286           if (cstr) {
6287             // Skip NULLs
6288             while (true) {
6289               const char *p = data.PeekCStr(offset);
6290               if ((p == NULL) || (*p != '\0'))
6291                 break;
6292               ++offset;
6293             }
6294             // Now skip all arguments
6295             for (uint32_t i = 0; i < argc; ++i) {
6296               data.GetCStr(&offset);
6297             }
6298 
6299             // Now iterate across all environment variables
6300             while ((cstr = data.GetCStr(&offset))) {
6301               if (strncmp(cstr, "SIMULATOR_UDID=", strlen("SIMULATOR_UDID=")) ==
6302                   0) {
6303                 is_ios_simulator = true;
6304                 break;
6305               }
6306               if (cstr[0] == '\0')
6307                 break;
6308             }
6309           }
6310         }
6311       }
6312       if (is_ios_simulator) {
6313 #if defined(TARGET_OS_TV) && TARGET_OS_TV == 1
6314         rep << "ostype:tvos;";
6315 #elif defined(TARGET_OS_WATCH) && TARGET_OS_WATCH == 1
6316         rep << "ostype:watchos;";
6317 #elif defined(TARGET_OS_BRIDGE) && TARGET_OS_BRIDGE == 1
6318         rep << "ostype:bridgeos;";
6319 #else
6320         rep << "ostype:ios;";
6321 #endif
6322       } else {
6323         rep << "ostype:macosx;";
6324       }
6325     }
6326   }
6327 
6328   rep << "vendor:apple;";
6329 
6330 #if defined(__LITTLE_ENDIAN__)
6331   rep << "endian:little;";
6332 #elif defined(__BIG_ENDIAN__)
6333   rep << "endian:big;";
6334 #elif defined(__PDP_ENDIAN__)
6335   rep << "endian:pdp;";
6336 #endif
6337 
6338   if (addr_size == 0) {
6339 #if (defined(__x86_64__) || defined(__i386__)) && defined(x86_THREAD_STATE)
6340     nub_thread_t thread = DNBProcessGetCurrentThreadMachPort(pid);
6341     kern_return_t kr;
6342     x86_thread_state_t gp_regs;
6343     mach_msg_type_number_t gp_count = x86_THREAD_STATE_COUNT;
6344     kr = thread_get_state(static_cast<thread_act_t>(thread), x86_THREAD_STATE,
6345                           (thread_state_t)&gp_regs, &gp_count);
6346     if (kr == KERN_SUCCESS) {
6347       if (gp_regs.tsh.flavor == x86_THREAD_STATE64)
6348         rep << "ptrsize:8;";
6349       else
6350         rep << "ptrsize:4;";
6351     }
6352 #elif defined(__arm__)
6353     rep << "ptrsize:4;";
6354 #elif (defined(__arm64__) || defined(__aarch64__)) &&                          \
6355     defined(ARM_UNIFIED_THREAD_STATE)
6356     nub_thread_t thread = DNBProcessGetCurrentThreadMachPort(pid);
6357     kern_return_t kr;
6358     arm_unified_thread_state_t gp_regs;
6359     mach_msg_type_number_t gp_count = ARM_UNIFIED_THREAD_STATE_COUNT;
6360     kr = thread_get_state(thread, ARM_UNIFIED_THREAD_STATE,
6361                           (thread_state_t)&gp_regs, &gp_count);
6362     if (kr == KERN_SUCCESS) {
6363       if (gp_regs.ash.flavor == ARM_THREAD_STATE64)
6364         rep << "ptrsize:8;";
6365       else
6366         rep << "ptrsize:4;";
6367     }
6368 #endif
6369   }
6370 
6371   return SendPacket(rep.str());
6372 }
6373 
6374 const RNBRemote::DispatchQueueOffsets *RNBRemote::GetDispatchQueueOffsets() {
6375   if (!m_dispatch_queue_offsets.IsValid() &&
6376       m_dispatch_queue_offsets_addr != INVALID_NUB_ADDRESS &&
6377       m_ctx.HasValidProcessID()) {
6378     nub_process_t pid = m_ctx.ProcessID();
6379     nub_size_t bytes_read = DNBProcessMemoryRead(
6380         pid, m_dispatch_queue_offsets_addr, sizeof(m_dispatch_queue_offsets),
6381         &m_dispatch_queue_offsets);
6382     if (bytes_read != sizeof(m_dispatch_queue_offsets))
6383       m_dispatch_queue_offsets.Clear();
6384   }
6385 
6386   if (m_dispatch_queue_offsets.IsValid())
6387     return &m_dispatch_queue_offsets;
6388   else
6389     return nullptr;
6390 }
6391 
6392 void RNBRemote::EnableCompressionNextSendPacket(compression_types type) {
6393   m_compression_mode = type;
6394   m_enable_compression_next_send_packet = true;
6395 }
6396 
6397 compression_types RNBRemote::GetCompressionType() {
6398   // The first packet we send back to the debugger after a QEnableCompression
6399   // request
6400   // should be uncompressed -- so we can indicate whether the compression was
6401   // enabled
6402   // or not via OK / Enn returns.  After that, all packets sent will be using
6403   // the
6404   // compression protocol.
6405 
6406   if (m_enable_compression_next_send_packet) {
6407     // One time, we send back "None" as our compression type
6408     m_enable_compression_next_send_packet = false;
6409     return compression_types::none;
6410   }
6411   return m_compression_mode;
6412 }
6413