xref: /llvm-project/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp (revision eb43e43bb5b2d19e14309e120cb8e66136ae7c82)
1 //===-- GDBRemoteCommunicationServerLLGS.cpp ------------------------------===//
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 #include <cerrno>
10 
11 #include "lldb/Host/Config.h"
12 
13 
14 #include <chrono>
15 #include <cstring>
16 #include <limits>
17 #include <thread>
18 
19 #include "GDBRemoteCommunicationServerLLGS.h"
20 #include "lldb/Host/ConnectionFileDescriptor.h"
21 #include "lldb/Host/Debug.h"
22 #include "lldb/Host/File.h"
23 #include "lldb/Host/FileAction.h"
24 #include "lldb/Host/FileSystem.h"
25 #include "lldb/Host/Host.h"
26 #include "lldb/Host/HostInfo.h"
27 #include "lldb/Host/PosixApi.h"
28 #include "lldb/Host/Socket.h"
29 #include "lldb/Host/common/NativeProcessProtocol.h"
30 #include "lldb/Host/common/NativeRegisterContext.h"
31 #include "lldb/Host/common/NativeThreadProtocol.h"
32 #include "lldb/Target/MemoryRegionInfo.h"
33 #include "lldb/Utility/Args.h"
34 #include "lldb/Utility/DataBuffer.h"
35 #include "lldb/Utility/Endian.h"
36 #include "lldb/Utility/GDBRemote.h"
37 #include "lldb/Utility/LLDBAssert.h"
38 #include "lldb/Utility/LLDBLog.h"
39 #include "lldb/Utility/Log.h"
40 #include "lldb/Utility/RegisterValue.h"
41 #include "lldb/Utility/State.h"
42 #include "lldb/Utility/StreamString.h"
43 #include "lldb/Utility/UnimplementedError.h"
44 #include "lldb/Utility/UriParser.h"
45 #include "llvm/ADT/Triple.h"
46 #include "llvm/Support/JSON.h"
47 #include "llvm/Support/ScopedPrinter.h"
48 
49 #include "ProcessGDBRemote.h"
50 #include "ProcessGDBRemoteLog.h"
51 #include "lldb/Utility/StringExtractorGDBRemote.h"
52 
53 using namespace lldb;
54 using namespace lldb_private;
55 using namespace lldb_private::process_gdb_remote;
56 using namespace llvm;
57 
58 // GDBRemote Errors
59 
60 namespace {
61 enum GDBRemoteServerError {
62   // Set to the first unused error number in literal form below
63   eErrorFirst = 29,
64   eErrorNoProcess = eErrorFirst,
65   eErrorResume,
66   eErrorExitStatus
67 };
68 }
69 
70 // GDBRemoteCommunicationServerLLGS constructor
71 GDBRemoteCommunicationServerLLGS::GDBRemoteCommunicationServerLLGS(
72     MainLoop &mainloop, const NativeProcessProtocol::Factory &process_factory)
73     : GDBRemoteCommunicationServerCommon("gdb-remote.server",
74                                          "gdb-remote.server.rx_packet"),
75       m_mainloop(mainloop), m_process_factory(process_factory),
76       m_current_process(nullptr), m_continue_process(nullptr),
77       m_stdio_communication("process.stdio") {
78   RegisterPacketHandlers();
79 }
80 
81 void GDBRemoteCommunicationServerLLGS::RegisterPacketHandlers() {
82   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_C,
83                                 &GDBRemoteCommunicationServerLLGS::Handle_C);
84   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_c,
85                                 &GDBRemoteCommunicationServerLLGS::Handle_c);
86   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_D,
87                                 &GDBRemoteCommunicationServerLLGS::Handle_D);
88   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_H,
89                                 &GDBRemoteCommunicationServerLLGS::Handle_H);
90   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_I,
91                                 &GDBRemoteCommunicationServerLLGS::Handle_I);
92   RegisterMemberFunctionHandler(
93       StringExtractorGDBRemote::eServerPacketType_interrupt,
94       &GDBRemoteCommunicationServerLLGS::Handle_interrupt);
95   RegisterMemberFunctionHandler(
96       StringExtractorGDBRemote::eServerPacketType_m,
97       &GDBRemoteCommunicationServerLLGS::Handle_memory_read);
98   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_M,
99                                 &GDBRemoteCommunicationServerLLGS::Handle_M);
100   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType__M,
101                                 &GDBRemoteCommunicationServerLLGS::Handle__M);
102   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType__m,
103                                 &GDBRemoteCommunicationServerLLGS::Handle__m);
104   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_p,
105                                 &GDBRemoteCommunicationServerLLGS::Handle_p);
106   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_P,
107                                 &GDBRemoteCommunicationServerLLGS::Handle_P);
108   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_qC,
109                                 &GDBRemoteCommunicationServerLLGS::Handle_qC);
110   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_T,
111                                 &GDBRemoteCommunicationServerLLGS::Handle_T);
112   RegisterMemberFunctionHandler(
113       StringExtractorGDBRemote::eServerPacketType_qfThreadInfo,
114       &GDBRemoteCommunicationServerLLGS::Handle_qfThreadInfo);
115   RegisterMemberFunctionHandler(
116       StringExtractorGDBRemote::eServerPacketType_qFileLoadAddress,
117       &GDBRemoteCommunicationServerLLGS::Handle_qFileLoadAddress);
118   RegisterMemberFunctionHandler(
119       StringExtractorGDBRemote::eServerPacketType_qGetWorkingDir,
120       &GDBRemoteCommunicationServerLLGS::Handle_qGetWorkingDir);
121   RegisterMemberFunctionHandler(
122       StringExtractorGDBRemote::eServerPacketType_QThreadSuffixSupported,
123       &GDBRemoteCommunicationServerLLGS::Handle_QThreadSuffixSupported);
124   RegisterMemberFunctionHandler(
125       StringExtractorGDBRemote::eServerPacketType_QListThreadsInStopReply,
126       &GDBRemoteCommunicationServerLLGS::Handle_QListThreadsInStopReply);
127   RegisterMemberFunctionHandler(
128       StringExtractorGDBRemote::eServerPacketType_qMemoryRegionInfo,
129       &GDBRemoteCommunicationServerLLGS::Handle_qMemoryRegionInfo);
130   RegisterMemberFunctionHandler(
131       StringExtractorGDBRemote::eServerPacketType_qMemoryRegionInfoSupported,
132       &GDBRemoteCommunicationServerLLGS::Handle_qMemoryRegionInfoSupported);
133   RegisterMemberFunctionHandler(
134       StringExtractorGDBRemote::eServerPacketType_qProcessInfo,
135       &GDBRemoteCommunicationServerLLGS::Handle_qProcessInfo);
136   RegisterMemberFunctionHandler(
137       StringExtractorGDBRemote::eServerPacketType_qRegisterInfo,
138       &GDBRemoteCommunicationServerLLGS::Handle_qRegisterInfo);
139   RegisterMemberFunctionHandler(
140       StringExtractorGDBRemote::eServerPacketType_QRestoreRegisterState,
141       &GDBRemoteCommunicationServerLLGS::Handle_QRestoreRegisterState);
142   RegisterMemberFunctionHandler(
143       StringExtractorGDBRemote::eServerPacketType_QSaveRegisterState,
144       &GDBRemoteCommunicationServerLLGS::Handle_QSaveRegisterState);
145   RegisterMemberFunctionHandler(
146       StringExtractorGDBRemote::eServerPacketType_QSetDisableASLR,
147       &GDBRemoteCommunicationServerLLGS::Handle_QSetDisableASLR);
148   RegisterMemberFunctionHandler(
149       StringExtractorGDBRemote::eServerPacketType_QSetWorkingDir,
150       &GDBRemoteCommunicationServerLLGS::Handle_QSetWorkingDir);
151   RegisterMemberFunctionHandler(
152       StringExtractorGDBRemote::eServerPacketType_qsThreadInfo,
153       &GDBRemoteCommunicationServerLLGS::Handle_qsThreadInfo);
154   RegisterMemberFunctionHandler(
155       StringExtractorGDBRemote::eServerPacketType_qThreadStopInfo,
156       &GDBRemoteCommunicationServerLLGS::Handle_qThreadStopInfo);
157   RegisterMemberFunctionHandler(
158       StringExtractorGDBRemote::eServerPacketType_jThreadsInfo,
159       &GDBRemoteCommunicationServerLLGS::Handle_jThreadsInfo);
160   RegisterMemberFunctionHandler(
161       StringExtractorGDBRemote::eServerPacketType_qWatchpointSupportInfo,
162       &GDBRemoteCommunicationServerLLGS::Handle_qWatchpointSupportInfo);
163   RegisterMemberFunctionHandler(
164       StringExtractorGDBRemote::eServerPacketType_qXfer,
165       &GDBRemoteCommunicationServerLLGS::Handle_qXfer);
166   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_s,
167                                 &GDBRemoteCommunicationServerLLGS::Handle_s);
168   RegisterMemberFunctionHandler(
169       StringExtractorGDBRemote::eServerPacketType_stop_reason,
170       &GDBRemoteCommunicationServerLLGS::Handle_stop_reason); // ?
171   RegisterMemberFunctionHandler(
172       StringExtractorGDBRemote::eServerPacketType_vAttach,
173       &GDBRemoteCommunicationServerLLGS::Handle_vAttach);
174   RegisterMemberFunctionHandler(
175       StringExtractorGDBRemote::eServerPacketType_vAttachWait,
176       &GDBRemoteCommunicationServerLLGS::Handle_vAttachWait);
177   RegisterMemberFunctionHandler(
178       StringExtractorGDBRemote::eServerPacketType_qVAttachOrWaitSupported,
179       &GDBRemoteCommunicationServerLLGS::Handle_qVAttachOrWaitSupported);
180   RegisterMemberFunctionHandler(
181       StringExtractorGDBRemote::eServerPacketType_vAttachOrWait,
182       &GDBRemoteCommunicationServerLLGS::Handle_vAttachOrWait);
183   RegisterMemberFunctionHandler(
184       StringExtractorGDBRemote::eServerPacketType_vCont,
185       &GDBRemoteCommunicationServerLLGS::Handle_vCont);
186   RegisterMemberFunctionHandler(
187       StringExtractorGDBRemote::eServerPacketType_vCont_actions,
188       &GDBRemoteCommunicationServerLLGS::Handle_vCont_actions);
189   RegisterMemberFunctionHandler(
190       StringExtractorGDBRemote::eServerPacketType_vRun,
191       &GDBRemoteCommunicationServerLLGS::Handle_vRun);
192   RegisterMemberFunctionHandler(
193       StringExtractorGDBRemote::eServerPacketType_x,
194       &GDBRemoteCommunicationServerLLGS::Handle_memory_read);
195   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_Z,
196                                 &GDBRemoteCommunicationServerLLGS::Handle_Z);
197   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_z,
198                                 &GDBRemoteCommunicationServerLLGS::Handle_z);
199   RegisterMemberFunctionHandler(
200       StringExtractorGDBRemote::eServerPacketType_QPassSignals,
201       &GDBRemoteCommunicationServerLLGS::Handle_QPassSignals);
202 
203   RegisterMemberFunctionHandler(
204       StringExtractorGDBRemote::eServerPacketType_jLLDBTraceSupported,
205       &GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceSupported);
206   RegisterMemberFunctionHandler(
207       StringExtractorGDBRemote::eServerPacketType_jLLDBTraceStart,
208       &GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceStart);
209   RegisterMemberFunctionHandler(
210       StringExtractorGDBRemote::eServerPacketType_jLLDBTraceStop,
211       &GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceStop);
212   RegisterMemberFunctionHandler(
213       StringExtractorGDBRemote::eServerPacketType_jLLDBTraceGetState,
214       &GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceGetState);
215   RegisterMemberFunctionHandler(
216       StringExtractorGDBRemote::eServerPacketType_jLLDBTraceGetBinaryData,
217       &GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceGetBinaryData);
218 
219   RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_g,
220                                 &GDBRemoteCommunicationServerLLGS::Handle_g);
221 
222   RegisterMemberFunctionHandler(
223       StringExtractorGDBRemote::eServerPacketType_qMemTags,
224       &GDBRemoteCommunicationServerLLGS::Handle_qMemTags);
225 
226   RegisterMemberFunctionHandler(
227       StringExtractorGDBRemote::eServerPacketType_QMemTags,
228       &GDBRemoteCommunicationServerLLGS::Handle_QMemTags);
229 
230   RegisterPacketHandler(StringExtractorGDBRemote::eServerPacketType_k,
231                         [this](StringExtractorGDBRemote packet, Status &error,
232                                bool &interrupt, bool &quit) {
233                           quit = true;
234                           return this->Handle_k(packet);
235                         });
236 
237   RegisterMemberFunctionHandler(
238       StringExtractorGDBRemote::eServerPacketType_vKill,
239       &GDBRemoteCommunicationServerLLGS::Handle_vKill);
240 
241   RegisterMemberFunctionHandler(
242       StringExtractorGDBRemote::eServerPacketType_qLLDBSaveCore,
243       &GDBRemoteCommunicationServerLLGS::Handle_qSaveCore);
244 
245   RegisterMemberFunctionHandler(
246       StringExtractorGDBRemote::eServerPacketType_QNonStop,
247       &GDBRemoteCommunicationServerLLGS::Handle_QNonStop);
248   RegisterMemberFunctionHandler(
249       StringExtractorGDBRemote::eServerPacketType_vStopped,
250       &GDBRemoteCommunicationServerLLGS::Handle_vStopped);
251   RegisterMemberFunctionHandler(
252       StringExtractorGDBRemote::eServerPacketType_vCtrlC,
253       &GDBRemoteCommunicationServerLLGS::Handle_vCtrlC);
254 }
255 
256 void GDBRemoteCommunicationServerLLGS::SetLaunchInfo(const ProcessLaunchInfo &info) {
257   m_process_launch_info = info;
258 }
259 
260 Status GDBRemoteCommunicationServerLLGS::LaunchProcess() {
261   Log *log = GetLog(LLDBLog::Process);
262 
263   if (!m_process_launch_info.GetArguments().GetArgumentCount())
264     return Status("%s: no process command line specified to launch",
265                   __FUNCTION__);
266 
267   const bool should_forward_stdio =
268       m_process_launch_info.GetFileActionForFD(STDIN_FILENO) == nullptr ||
269       m_process_launch_info.GetFileActionForFD(STDOUT_FILENO) == nullptr ||
270       m_process_launch_info.GetFileActionForFD(STDERR_FILENO) == nullptr;
271   m_process_launch_info.SetLaunchInSeparateProcessGroup(true);
272   m_process_launch_info.GetFlags().Set(eLaunchFlagDebug);
273 
274   if (should_forward_stdio) {
275     // Temporarily relax the following for Windows until we can take advantage
276     // of the recently added pty support. This doesn't really affect the use of
277     // lldb-server on Windows.
278 #if !defined(_WIN32)
279     if (llvm::Error Err = m_process_launch_info.SetUpPtyRedirection())
280       return Status(std::move(Err));
281 #endif
282   }
283 
284   {
285     std::lock_guard<std::recursive_mutex> guard(m_debugged_process_mutex);
286     assert(m_debugged_processes.empty() && "lldb-server creating debugged "
287                                            "process but one already exists");
288     auto process_or =
289         m_process_factory.Launch(m_process_launch_info, *this, m_mainloop);
290     if (!process_or)
291       return Status(process_or.takeError());
292     m_continue_process = m_current_process = process_or->get();
293     m_debugged_processes.emplace(
294         m_current_process->GetID(),
295         DebuggedProcess{std::move(*process_or), DebuggedProcess::Flag{}});
296   }
297 
298   SetEnabledExtensions(*m_current_process);
299 
300   // Handle mirroring of inferior stdout/stderr over the gdb-remote protocol as
301   // needed. llgs local-process debugging may specify PTY paths, which will
302   // make these file actions non-null process launch -i/e/o will also make
303   // these file actions non-null nullptr means that the traffic is expected to
304   // flow over gdb-remote protocol
305   if (should_forward_stdio) {
306     // nullptr means it's not redirected to file or pty (in case of LLGS local)
307     // at least one of stdio will be transferred pty<->gdb-remote we need to
308     // give the pty primary handle to this object to read and/or write
309     LLDB_LOG(log,
310              "pid = {0}: setting up stdout/stderr redirection via $O "
311              "gdb-remote commands",
312              m_current_process->GetID());
313 
314     // Setup stdout/stderr mapping from inferior to $O
315     auto terminal_fd = m_current_process->GetTerminalFileDescriptor();
316     if (terminal_fd >= 0) {
317       LLDB_LOGF(log,
318                 "ProcessGDBRemoteCommunicationServerLLGS::%s setting "
319                 "inferior STDIO fd to %d",
320                 __FUNCTION__, terminal_fd);
321       Status status = SetSTDIOFileDescriptor(terminal_fd);
322       if (status.Fail())
323         return status;
324     } else {
325       LLDB_LOGF(log,
326                 "ProcessGDBRemoteCommunicationServerLLGS::%s ignoring "
327                 "inferior STDIO since terminal fd reported as %d",
328                 __FUNCTION__, terminal_fd);
329     }
330   } else {
331     LLDB_LOG(log,
332              "pid = {0} skipping stdout/stderr redirection via $O: inferior "
333              "will communicate over client-provided file descriptors",
334              m_current_process->GetID());
335   }
336 
337   printf("Launched '%s' as process %" PRIu64 "...\n",
338          m_process_launch_info.GetArguments().GetArgumentAtIndex(0),
339          m_current_process->GetID());
340 
341   return Status();
342 }
343 
344 Status GDBRemoteCommunicationServerLLGS::AttachToProcess(lldb::pid_t pid) {
345   Log *log = GetLog(LLDBLog::Process);
346   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s pid %" PRIu64,
347             __FUNCTION__, pid);
348 
349   // Before we try to attach, make sure we aren't already monitoring something
350   // else.
351   if (!m_debugged_processes.empty())
352     return Status("cannot attach to process %" PRIu64
353                   " when another process with pid %" PRIu64
354                   " is being debugged.",
355                   pid, m_current_process->GetID());
356 
357   // Try to attach.
358   auto process_or = m_process_factory.Attach(pid, *this, m_mainloop);
359   if (!process_or) {
360     Status status(process_or.takeError());
361     llvm::errs() << llvm::formatv("failed to attach to process {0}: {1}\n", pid,
362                                   status);
363     return status;
364   }
365   m_continue_process = m_current_process = process_or->get();
366   m_debugged_processes.emplace(
367       m_current_process->GetID(),
368       DebuggedProcess{std::move(*process_or), DebuggedProcess::Flag{}});
369   SetEnabledExtensions(*m_current_process);
370 
371   // Setup stdout/stderr mapping from inferior.
372   auto terminal_fd = m_current_process->GetTerminalFileDescriptor();
373   if (terminal_fd >= 0) {
374     LLDB_LOGF(log,
375               "ProcessGDBRemoteCommunicationServerLLGS::%s setting "
376               "inferior STDIO fd to %d",
377               __FUNCTION__, terminal_fd);
378     Status status = SetSTDIOFileDescriptor(terminal_fd);
379     if (status.Fail())
380       return status;
381   } else {
382     LLDB_LOGF(log,
383               "ProcessGDBRemoteCommunicationServerLLGS::%s ignoring "
384               "inferior STDIO since terminal fd reported as %d",
385               __FUNCTION__, terminal_fd);
386   }
387 
388   printf("Attached to process %" PRIu64 "...\n", pid);
389   return Status();
390 }
391 
392 Status GDBRemoteCommunicationServerLLGS::AttachWaitProcess(
393     llvm::StringRef process_name, bool include_existing) {
394   Log *log = GetLog(LLDBLog::Process);
395 
396   std::chrono::milliseconds polling_interval = std::chrono::milliseconds(1);
397 
398   // Create the matcher used to search the process list.
399   ProcessInstanceInfoList exclusion_list;
400   ProcessInstanceInfoMatch match_info;
401   match_info.GetProcessInfo().GetExecutableFile().SetFile(
402       process_name, llvm::sys::path::Style::native);
403   match_info.SetNameMatchType(NameMatch::Equals);
404 
405   if (include_existing) {
406     LLDB_LOG(log, "including existing processes in search");
407   } else {
408     // Create the excluded process list before polling begins.
409     Host::FindProcesses(match_info, exclusion_list);
410     LLDB_LOG(log, "placed '{0}' processes in the exclusion list.",
411              exclusion_list.size());
412   }
413 
414   LLDB_LOG(log, "waiting for '{0}' to appear", process_name);
415 
416   auto is_in_exclusion_list =
417       [&exclusion_list](const ProcessInstanceInfo &info) {
418         for (auto &excluded : exclusion_list) {
419           if (excluded.GetProcessID() == info.GetProcessID())
420             return true;
421         }
422         return false;
423       };
424 
425   ProcessInstanceInfoList loop_process_list;
426   while (true) {
427     loop_process_list.clear();
428     if (Host::FindProcesses(match_info, loop_process_list)) {
429       // Remove all the elements that are in the exclusion list.
430       llvm::erase_if(loop_process_list, is_in_exclusion_list);
431 
432       // One match! We found the desired process.
433       if (loop_process_list.size() == 1) {
434         auto matching_process_pid = loop_process_list[0].GetProcessID();
435         LLDB_LOG(log, "found pid {0}", matching_process_pid);
436         return AttachToProcess(matching_process_pid);
437       }
438 
439       // Multiple matches! Return an error reporting the PIDs we found.
440       if (loop_process_list.size() > 1) {
441         StreamString error_stream;
442         error_stream.Format(
443             "Multiple executables with name: '{0}' found. Pids: ",
444             process_name);
445         for (size_t i = 0; i < loop_process_list.size() - 1; ++i) {
446           error_stream.Format("{0}, ", loop_process_list[i].GetProcessID());
447         }
448         error_stream.Format("{0}.", loop_process_list.back().GetProcessID());
449 
450         Status error;
451         error.SetErrorString(error_stream.GetString());
452         return error;
453       }
454     }
455     // No matches, we have not found the process. Sleep until next poll.
456     LLDB_LOG(log, "sleep {0} seconds", polling_interval);
457     std::this_thread::sleep_for(polling_interval);
458   }
459 }
460 
461 void GDBRemoteCommunicationServerLLGS::InitializeDelegate(
462     NativeProcessProtocol *process) {
463   assert(process && "process cannot be NULL");
464   Log *log = GetLog(LLDBLog::Process);
465   if (log) {
466     LLDB_LOGF(log,
467               "GDBRemoteCommunicationServerLLGS::%s called with "
468               "NativeProcessProtocol pid %" PRIu64 ", current state: %s",
469               __FUNCTION__, process->GetID(),
470               StateAsCString(process->GetState()));
471   }
472 }
473 
474 GDBRemoteCommunication::PacketResult
475 GDBRemoteCommunicationServerLLGS::SendWResponse(
476     NativeProcessProtocol *process) {
477   assert(process && "process cannot be NULL");
478   Log *log = GetLog(LLDBLog::Process);
479 
480   // send W notification
481   auto wait_status = process->GetExitStatus();
482   if (!wait_status) {
483     LLDB_LOG(log, "pid = {0}, failed to retrieve process exit status",
484              process->GetID());
485 
486     StreamGDBRemote response;
487     response.PutChar('E');
488     response.PutHex8(GDBRemoteServerError::eErrorExitStatus);
489     return SendPacketNoLock(response.GetString());
490   }
491 
492   LLDB_LOG(log, "pid = {0}, returning exit type {1}", process->GetID(),
493            *wait_status);
494 
495   // If the process was killed through vKill, return "OK".
496   if (bool(m_debugged_processes.at(process->GetID()).flags &
497            DebuggedProcess::Flag::vkilled))
498     return SendOKResponse();
499 
500   StreamGDBRemote response;
501   response.Format("{0:g}", *wait_status);
502   if (bool(m_extensions_supported &
503            NativeProcessProtocol::Extension::multiprocess))
504     response.Format(";process:{0:x-}", process->GetID());
505   if (m_non_stop)
506     return SendNotificationPacketNoLock("Stop", m_stop_notification_queue,
507                                         response.GetString());
508   return SendPacketNoLock(response.GetString());
509 }
510 
511 static void AppendHexValue(StreamString &response, const uint8_t *buf,
512                            uint32_t buf_size, bool swap) {
513   int64_t i;
514   if (swap) {
515     for (i = buf_size - 1; i >= 0; i--)
516       response.PutHex8(buf[i]);
517   } else {
518     for (i = 0; i < buf_size; i++)
519       response.PutHex8(buf[i]);
520   }
521 }
522 
523 static llvm::StringRef GetEncodingNameOrEmpty(const RegisterInfo &reg_info) {
524   switch (reg_info.encoding) {
525   case eEncodingUint:
526     return "uint";
527   case eEncodingSint:
528     return "sint";
529   case eEncodingIEEE754:
530     return "ieee754";
531   case eEncodingVector:
532     return "vector";
533   default:
534     return "";
535   }
536 }
537 
538 static llvm::StringRef GetFormatNameOrEmpty(const RegisterInfo &reg_info) {
539   switch (reg_info.format) {
540   case eFormatBinary:
541     return "binary";
542   case eFormatDecimal:
543     return "decimal";
544   case eFormatHex:
545     return "hex";
546   case eFormatFloat:
547     return "float";
548   case eFormatVectorOfSInt8:
549     return "vector-sint8";
550   case eFormatVectorOfUInt8:
551     return "vector-uint8";
552   case eFormatVectorOfSInt16:
553     return "vector-sint16";
554   case eFormatVectorOfUInt16:
555     return "vector-uint16";
556   case eFormatVectorOfSInt32:
557     return "vector-sint32";
558   case eFormatVectorOfUInt32:
559     return "vector-uint32";
560   case eFormatVectorOfFloat32:
561     return "vector-float32";
562   case eFormatVectorOfUInt64:
563     return "vector-uint64";
564   case eFormatVectorOfUInt128:
565     return "vector-uint128";
566   default:
567     return "";
568   };
569 }
570 
571 static llvm::StringRef GetKindGenericOrEmpty(const RegisterInfo &reg_info) {
572   switch (reg_info.kinds[RegisterKind::eRegisterKindGeneric]) {
573   case LLDB_REGNUM_GENERIC_PC:
574     return "pc";
575   case LLDB_REGNUM_GENERIC_SP:
576     return "sp";
577   case LLDB_REGNUM_GENERIC_FP:
578     return "fp";
579   case LLDB_REGNUM_GENERIC_RA:
580     return "ra";
581   case LLDB_REGNUM_GENERIC_FLAGS:
582     return "flags";
583   case LLDB_REGNUM_GENERIC_ARG1:
584     return "arg1";
585   case LLDB_REGNUM_GENERIC_ARG2:
586     return "arg2";
587   case LLDB_REGNUM_GENERIC_ARG3:
588     return "arg3";
589   case LLDB_REGNUM_GENERIC_ARG4:
590     return "arg4";
591   case LLDB_REGNUM_GENERIC_ARG5:
592     return "arg5";
593   case LLDB_REGNUM_GENERIC_ARG6:
594     return "arg6";
595   case LLDB_REGNUM_GENERIC_ARG7:
596     return "arg7";
597   case LLDB_REGNUM_GENERIC_ARG8:
598     return "arg8";
599   default:
600     return "";
601   }
602 }
603 
604 static void CollectRegNums(const uint32_t *reg_num, StreamString &response,
605                            bool usehex) {
606   for (int i = 0; *reg_num != LLDB_INVALID_REGNUM; ++reg_num, ++i) {
607     if (i > 0)
608       response.PutChar(',');
609     if (usehex)
610       response.Printf("%" PRIx32, *reg_num);
611     else
612       response.Printf("%" PRIu32, *reg_num);
613   }
614 }
615 
616 static void WriteRegisterValueInHexFixedWidth(
617     StreamString &response, NativeRegisterContext &reg_ctx,
618     const RegisterInfo &reg_info, const RegisterValue *reg_value_p,
619     lldb::ByteOrder byte_order) {
620   RegisterValue reg_value;
621   if (!reg_value_p) {
622     Status error = reg_ctx.ReadRegister(&reg_info, reg_value);
623     if (error.Success())
624       reg_value_p = &reg_value;
625     // else log.
626   }
627 
628   if (reg_value_p) {
629     AppendHexValue(response, (const uint8_t *)reg_value_p->GetBytes(),
630                    reg_value_p->GetByteSize(),
631                    byte_order == lldb::eByteOrderLittle);
632   } else {
633     // Zero-out any unreadable values.
634     if (reg_info.byte_size > 0) {
635       std::basic_string<uint8_t> zeros(reg_info.byte_size, '\0');
636       AppendHexValue(response, zeros.data(), zeros.size(), false);
637     }
638   }
639 }
640 
641 static llvm::Optional<json::Object>
642 GetRegistersAsJSON(NativeThreadProtocol &thread) {
643   Log *log = GetLog(LLDBLog::Thread);
644 
645   NativeRegisterContext& reg_ctx = thread.GetRegisterContext();
646 
647   json::Object register_object;
648 
649 #ifdef LLDB_JTHREADSINFO_FULL_REGISTER_SET
650   const auto expedited_regs =
651       reg_ctx.GetExpeditedRegisters(ExpeditedRegs::Full);
652 #else
653   const auto expedited_regs =
654       reg_ctx.GetExpeditedRegisters(ExpeditedRegs::Minimal);
655 #endif
656   if (expedited_regs.empty())
657     return llvm::None;
658 
659   for (auto &reg_num : expedited_regs) {
660     const RegisterInfo *const reg_info_p =
661         reg_ctx.GetRegisterInfoAtIndex(reg_num);
662     if (reg_info_p == nullptr) {
663       LLDB_LOGF(log,
664                 "%s failed to get register info for register index %" PRIu32,
665                 __FUNCTION__, reg_num);
666       continue;
667     }
668 
669     if (reg_info_p->value_regs != nullptr)
670       continue; // Only expedite registers that are not contained in other
671                 // registers.
672 
673     RegisterValue reg_value;
674     Status error = reg_ctx.ReadRegister(reg_info_p, reg_value);
675     if (error.Fail()) {
676       LLDB_LOGF(log, "%s failed to read register '%s' index %" PRIu32 ": %s",
677                 __FUNCTION__,
678                 reg_info_p->name ? reg_info_p->name : "<unnamed-register>",
679                 reg_num, error.AsCString());
680       continue;
681     }
682 
683     StreamString stream;
684     WriteRegisterValueInHexFixedWidth(stream, reg_ctx, *reg_info_p,
685                                       &reg_value, lldb::eByteOrderBig);
686 
687     register_object.try_emplace(llvm::to_string(reg_num),
688                                 stream.GetString().str());
689   }
690 
691   return register_object;
692 }
693 
694 static const char *GetStopReasonString(StopReason stop_reason) {
695   switch (stop_reason) {
696   case eStopReasonTrace:
697     return "trace";
698   case eStopReasonBreakpoint:
699     return "breakpoint";
700   case eStopReasonWatchpoint:
701     return "watchpoint";
702   case eStopReasonSignal:
703     return "signal";
704   case eStopReasonException:
705     return "exception";
706   case eStopReasonExec:
707     return "exec";
708   case eStopReasonProcessorTrace:
709     return "processor trace";
710   case eStopReasonFork:
711     return "fork";
712   case eStopReasonVFork:
713     return "vfork";
714   case eStopReasonVForkDone:
715     return "vforkdone";
716   case eStopReasonInstrumentation:
717   case eStopReasonInvalid:
718   case eStopReasonPlanComplete:
719   case eStopReasonThreadExiting:
720   case eStopReasonNone:
721     break; // ignored
722   }
723   return nullptr;
724 }
725 
726 static llvm::Expected<json::Array>
727 GetJSONThreadsInfo(NativeProcessProtocol &process, bool abridged) {
728   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
729 
730   json::Array threads_array;
731 
732   // Ensure we can get info on the given thread.
733   for (NativeThreadProtocol &thread : process.Threads()) {
734     lldb::tid_t tid = thread.GetID();
735     // Grab the reason this thread stopped.
736     struct ThreadStopInfo tid_stop_info;
737     std::string description;
738     if (!thread.GetStopReason(tid_stop_info, description))
739       return llvm::make_error<llvm::StringError>(
740           "failed to get stop reason", llvm::inconvertibleErrorCode());
741 
742     const int signum = tid_stop_info.signo;
743     if (log) {
744       LLDB_LOGF(log,
745                 "GDBRemoteCommunicationServerLLGS::%s pid %" PRIu64
746                 " tid %" PRIu64
747                 " got signal signo = %d, reason = %d, exc_type = %" PRIu64,
748                 __FUNCTION__, process.GetID(), tid, signum,
749                 tid_stop_info.reason, tid_stop_info.details.exception.type);
750     }
751 
752     json::Object thread_obj;
753 
754     if (!abridged) {
755       if (llvm::Optional<json::Object> registers = GetRegistersAsJSON(thread))
756         thread_obj.try_emplace("registers", std::move(*registers));
757     }
758 
759     thread_obj.try_emplace("tid", static_cast<int64_t>(tid));
760 
761     if (signum != 0)
762       thread_obj.try_emplace("signal", signum);
763 
764     const std::string thread_name = thread.GetName();
765     if (!thread_name.empty())
766       thread_obj.try_emplace("name", thread_name);
767 
768     const char *stop_reason = GetStopReasonString(tid_stop_info.reason);
769     if (stop_reason)
770       thread_obj.try_emplace("reason", stop_reason);
771 
772     if (!description.empty())
773       thread_obj.try_emplace("description", description);
774 
775     if ((tid_stop_info.reason == eStopReasonException) &&
776         tid_stop_info.details.exception.type) {
777       thread_obj.try_emplace(
778           "metype", static_cast<int64_t>(tid_stop_info.details.exception.type));
779 
780       json::Array medata_array;
781       for (uint32_t i = 0; i < tid_stop_info.details.exception.data_count;
782            ++i) {
783         medata_array.push_back(
784             static_cast<int64_t>(tid_stop_info.details.exception.data[i]));
785       }
786       thread_obj.try_emplace("medata", std::move(medata_array));
787     }
788     threads_array.push_back(std::move(thread_obj));
789   }
790   return threads_array;
791 }
792 
793 StreamString
794 GDBRemoteCommunicationServerLLGS::PrepareStopReplyPacketForThread(
795     NativeThreadProtocol &thread) {
796   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
797 
798   NativeProcessProtocol &process = thread.GetProcess();
799 
800   LLDB_LOG(log, "preparing packet for pid {0} tid {1}", process.GetID(),
801            thread.GetID());
802 
803   // Grab the reason this thread stopped.
804   StreamString response;
805   struct ThreadStopInfo tid_stop_info;
806   std::string description;
807   if (!thread.GetStopReason(tid_stop_info, description))
808     return response;
809 
810   // FIXME implement register handling for exec'd inferiors.
811   // if (tid_stop_info.reason == eStopReasonExec) {
812   //     const bool force = true;
813   //     InitializeRegisters(force);
814   // }
815 
816   // Output the T packet with the thread
817   response.PutChar('T');
818   int signum = tid_stop_info.signo;
819   LLDB_LOG(
820       log,
821       "pid {0}, tid {1}, got signal signo = {2}, reason = {3}, exc_type = {4}",
822       process.GetID(), thread.GetID(), signum, int(tid_stop_info.reason),
823       tid_stop_info.details.exception.type);
824 
825   // Print the signal number.
826   response.PutHex8(signum & 0xff);
827 
828   // Include the (pid and) tid.
829   response.PutCString("thread:");
830   AppendThreadIDToResponse(response, process.GetID(), thread.GetID());
831   response.PutChar(';');
832 
833   // Include the thread name if there is one.
834   const std::string thread_name = thread.GetName();
835   if (!thread_name.empty()) {
836     size_t thread_name_len = thread_name.length();
837 
838     if (::strcspn(thread_name.c_str(), "$#+-;:") == thread_name_len) {
839       response.PutCString("name:");
840       response.PutCString(thread_name);
841     } else {
842       // The thread name contains special chars, send as hex bytes.
843       response.PutCString("hexname:");
844       response.PutStringAsRawHex8(thread_name);
845     }
846     response.PutChar(';');
847   }
848 
849   // If a 'QListThreadsInStopReply' was sent to enable this feature, we will
850   // send all thread IDs back in the "threads" key whose value is a list of hex
851   // thread IDs separated by commas:
852   //  "threads:10a,10b,10c;"
853   // This will save the debugger from having to send a pair of qfThreadInfo and
854   // qsThreadInfo packets, but it also might take a lot of room in the stop
855   // reply packet, so it must be enabled only on systems where there are no
856   // limits on packet lengths.
857   if (m_list_threads_in_stop_reply) {
858     response.PutCString("threads:");
859 
860     uint32_t thread_num = 0;
861     for (NativeThreadProtocol &listed_thread : process.Threads()) {
862       if (thread_num > 0)
863         response.PutChar(',');
864       response.Printf("%" PRIx64, listed_thread.GetID());
865       ++thread_num;
866     }
867     response.PutChar(';');
868 
869     // Include JSON info that describes the stop reason for any threads that
870     // actually have stop reasons. We use the new "jstopinfo" key whose values
871     // is hex ascii JSON that contains the thread IDs thread stop info only for
872     // threads that have stop reasons. Only send this if we have more than one
873     // thread otherwise this packet has all the info it needs.
874     if (thread_num > 1) {
875       const bool threads_with_valid_stop_info_only = true;
876       llvm::Expected<json::Array> threads_info = GetJSONThreadsInfo(
877           *m_current_process, threads_with_valid_stop_info_only);
878       if (threads_info) {
879         response.PutCString("jstopinfo:");
880         StreamString unescaped_response;
881         unescaped_response.AsRawOstream() << std::move(*threads_info);
882         response.PutStringAsRawHex8(unescaped_response.GetData());
883         response.PutChar(';');
884       } else {
885         LLDB_LOG_ERROR(log, threads_info.takeError(),
886                        "failed to prepare a jstopinfo field for pid {1}: {0}",
887                        process.GetID());
888       }
889     }
890 
891     response.PutCString("thread-pcs");
892     char delimiter = ':';
893     for (NativeThreadProtocol &thread : process.Threads()) {
894       NativeRegisterContext &reg_ctx = thread.GetRegisterContext();
895 
896       uint32_t reg_to_read = reg_ctx.ConvertRegisterKindToRegisterNumber(
897           eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
898       const RegisterInfo *const reg_info_p =
899           reg_ctx.GetRegisterInfoAtIndex(reg_to_read);
900 
901       RegisterValue reg_value;
902       Status error = reg_ctx.ReadRegister(reg_info_p, reg_value);
903       if (error.Fail()) {
904         LLDB_LOGF(log, "%s failed to read register '%s' index %" PRIu32 ": %s",
905                   __FUNCTION__,
906                   reg_info_p->name ? reg_info_p->name : "<unnamed-register>",
907                   reg_to_read, error.AsCString());
908         continue;
909       }
910 
911       response.PutChar(delimiter);
912       delimiter = ',';
913       WriteRegisterValueInHexFixedWidth(response, reg_ctx, *reg_info_p,
914                                         &reg_value, endian::InlHostByteOrder());
915     }
916 
917     response.PutChar(';');
918   }
919 
920   //
921   // Expedite registers.
922   //
923 
924   // Grab the register context.
925   NativeRegisterContext &reg_ctx = thread.GetRegisterContext();
926   const auto expedited_regs =
927       reg_ctx.GetExpeditedRegisters(ExpeditedRegs::Full);
928 
929   for (auto &reg_num : expedited_regs) {
930     const RegisterInfo *const reg_info_p =
931         reg_ctx.GetRegisterInfoAtIndex(reg_num);
932     // Only expediate registers that are not contained in other registers.
933     if (reg_info_p != nullptr && reg_info_p->value_regs == nullptr) {
934       RegisterValue reg_value;
935       Status error = reg_ctx.ReadRegister(reg_info_p, reg_value);
936       if (error.Success()) {
937         response.Printf("%.02x:", reg_num);
938         WriteRegisterValueInHexFixedWidth(response, reg_ctx, *reg_info_p,
939                                           &reg_value, lldb::eByteOrderBig);
940         response.PutChar(';');
941       } else {
942         LLDB_LOGF(log,
943                   "GDBRemoteCommunicationServerLLGS::%s failed to read "
944                   "register '%s' index %" PRIu32 ": %s",
945                   __FUNCTION__,
946                   reg_info_p->name ? reg_info_p->name : "<unnamed-register>",
947                   reg_num, error.AsCString());
948       }
949     }
950   }
951 
952   const char *reason_str = GetStopReasonString(tid_stop_info.reason);
953   if (reason_str != nullptr) {
954     response.Printf("reason:%s;", reason_str);
955   }
956 
957   if (!description.empty()) {
958     // Description may contains special chars, send as hex bytes.
959     response.PutCString("description:");
960     response.PutStringAsRawHex8(description);
961     response.PutChar(';');
962   } else if ((tid_stop_info.reason == eStopReasonException) &&
963              tid_stop_info.details.exception.type) {
964     response.PutCString("metype:");
965     response.PutHex64(tid_stop_info.details.exception.type);
966     response.PutCString(";mecount:");
967     response.PutHex32(tid_stop_info.details.exception.data_count);
968     response.PutChar(';');
969 
970     for (uint32_t i = 0; i < tid_stop_info.details.exception.data_count; ++i) {
971       response.PutCString("medata:");
972       response.PutHex64(tid_stop_info.details.exception.data[i]);
973       response.PutChar(';');
974     }
975   }
976 
977   // Include child process PID/TID for forks.
978   if (tid_stop_info.reason == eStopReasonFork ||
979       tid_stop_info.reason == eStopReasonVFork) {
980     assert(bool(m_extensions_supported &
981                 NativeProcessProtocol::Extension::multiprocess));
982     if (tid_stop_info.reason == eStopReasonFork)
983       assert(bool(m_extensions_supported &
984                   NativeProcessProtocol::Extension::fork));
985     if (tid_stop_info.reason == eStopReasonVFork)
986       assert(bool(m_extensions_supported &
987                   NativeProcessProtocol::Extension::vfork));
988     response.Printf("%s:p%" PRIx64 ".%" PRIx64 ";", reason_str,
989                     tid_stop_info.details.fork.child_pid,
990                     tid_stop_info.details.fork.child_tid);
991   }
992 
993   return response;
994 }
995 
996 GDBRemoteCommunication::PacketResult
997 GDBRemoteCommunicationServerLLGS::SendStopReplyPacketForThread(
998     NativeProcessProtocol &process, lldb::tid_t tid, bool force_synchronous) {
999   // Ensure we can get info on the given thread.
1000   NativeThreadProtocol *thread = process.GetThreadByID(tid);
1001   if (!thread)
1002     return SendErrorResponse(51);
1003 
1004   StreamString response = PrepareStopReplyPacketForThread(*thread);
1005   if (response.Empty())
1006     return SendErrorResponse(42);
1007 
1008   if (m_non_stop && !force_synchronous) {
1009     PacketResult ret = SendNotificationPacketNoLock(
1010         "Stop", m_stop_notification_queue, response.GetString());
1011     // Queue notification events for the remaining threads.
1012     EnqueueStopReplyPackets(tid);
1013     return ret;
1014   }
1015 
1016   return SendPacketNoLock(response.GetString());
1017 }
1018 
1019 void GDBRemoteCommunicationServerLLGS::EnqueueStopReplyPackets(
1020     lldb::tid_t thread_to_skip) {
1021   if (!m_non_stop)
1022     return;
1023 
1024   for (NativeThreadProtocol &listed_thread : m_current_process->Threads()) {
1025     if (listed_thread.GetID() != thread_to_skip)
1026       m_stop_notification_queue.push_back(
1027           PrepareStopReplyPacketForThread(listed_thread).GetString().str());
1028   }
1029 }
1030 
1031 void GDBRemoteCommunicationServerLLGS::HandleInferiorState_Exited(
1032     NativeProcessProtocol *process) {
1033   assert(process && "process cannot be NULL");
1034 
1035   Log *log = GetLog(LLDBLog::Process);
1036   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s called", __FUNCTION__);
1037 
1038   PacketResult result = SendStopReasonForState(
1039       *process, StateType::eStateExited, /*force_synchronous=*/false);
1040   if (result != PacketResult::Success) {
1041     LLDB_LOGF(log,
1042               "GDBRemoteCommunicationServerLLGS::%s failed to send stop "
1043               "notification for PID %" PRIu64 ", state: eStateExited",
1044               __FUNCTION__, process->GetID());
1045   }
1046 
1047   if (m_current_process == process)
1048     m_current_process = nullptr;
1049   if (m_continue_process == process)
1050     m_continue_process = nullptr;
1051 
1052   lldb::pid_t pid = process->GetID();
1053   m_mainloop.AddPendingCallback([this, pid](MainLoopBase &loop) {
1054     auto find_it = m_debugged_processes.find(pid);
1055     assert(find_it != m_debugged_processes.end());
1056     bool vkilled = bool(find_it->second.flags & DebuggedProcess::Flag::vkilled);
1057     m_debugged_processes.erase(find_it);
1058     // Terminate the main loop only if vKill has not been used.
1059     // When running in non-stop mode, wait for the vStopped to clear
1060     // the notification queue.
1061     if (m_debugged_processes.empty() && !m_non_stop && !vkilled) {
1062       // Close the pipe to the inferior terminal i/o if we launched it and set
1063       // one up.
1064       MaybeCloseInferiorTerminalConnection();
1065 
1066       // We are ready to exit the debug monitor.
1067       m_exit_now = true;
1068       loop.RequestTermination();
1069     }
1070   });
1071 }
1072 
1073 void GDBRemoteCommunicationServerLLGS::HandleInferiorState_Stopped(
1074     NativeProcessProtocol *process) {
1075   assert(process && "process cannot be NULL");
1076 
1077   Log *log = GetLog(LLDBLog::Process);
1078   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s called", __FUNCTION__);
1079 
1080   PacketResult result = SendStopReasonForState(
1081       *process, StateType::eStateStopped, /*force_synchronous=*/false);
1082   if (result != PacketResult::Success) {
1083     LLDB_LOGF(log,
1084               "GDBRemoteCommunicationServerLLGS::%s failed to send stop "
1085               "notification for PID %" PRIu64 ", state: eStateExited",
1086               __FUNCTION__, process->GetID());
1087   }
1088 }
1089 
1090 void GDBRemoteCommunicationServerLLGS::ProcessStateChanged(
1091     NativeProcessProtocol *process, lldb::StateType state) {
1092   assert(process && "process cannot be NULL");
1093   Log *log = GetLog(LLDBLog::Process);
1094   if (log) {
1095     LLDB_LOGF(log,
1096               "GDBRemoteCommunicationServerLLGS::%s called with "
1097               "NativeProcessProtocol pid %" PRIu64 ", state: %s",
1098               __FUNCTION__, process->GetID(), StateAsCString(state));
1099   }
1100 
1101   switch (state) {
1102   case StateType::eStateRunning:
1103     break;
1104 
1105   case StateType::eStateStopped:
1106     // Make sure we get all of the pending stdout/stderr from the inferior and
1107     // send it to the lldb host before we send the state change notification
1108     SendProcessOutput();
1109     // Then stop the forwarding, so that any late output (see llvm.org/pr25652)
1110     // does not interfere with our protocol.
1111     StopSTDIOForwarding();
1112     HandleInferiorState_Stopped(process);
1113     break;
1114 
1115   case StateType::eStateExited:
1116     // Same as above
1117     SendProcessOutput();
1118     StopSTDIOForwarding();
1119     HandleInferiorState_Exited(process);
1120     break;
1121 
1122   default:
1123     if (log) {
1124       LLDB_LOGF(log,
1125                 "GDBRemoteCommunicationServerLLGS::%s didn't handle state "
1126                 "change for pid %" PRIu64 ", new state: %s",
1127                 __FUNCTION__, process->GetID(), StateAsCString(state));
1128     }
1129     break;
1130   }
1131 }
1132 
1133 void GDBRemoteCommunicationServerLLGS::DidExec(NativeProcessProtocol *process) {
1134   ClearProcessSpecificData();
1135 }
1136 
1137 void GDBRemoteCommunicationServerLLGS::NewSubprocess(
1138     NativeProcessProtocol *parent_process,
1139     std::unique_ptr<NativeProcessProtocol> child_process) {
1140   lldb::pid_t child_pid = child_process->GetID();
1141   assert(child_pid != LLDB_INVALID_PROCESS_ID);
1142   assert(m_debugged_processes.find(child_pid) == m_debugged_processes.end());
1143   m_debugged_processes.emplace(
1144       child_pid,
1145       DebuggedProcess{std::move(child_process), DebuggedProcess::Flag{}});
1146 }
1147 
1148 void GDBRemoteCommunicationServerLLGS::DataAvailableCallback() {
1149   Log *log = GetLog(GDBRLog::Comm);
1150 
1151   bool interrupt = false;
1152   bool done = false;
1153   Status error;
1154   while (true) {
1155     const PacketResult result = GetPacketAndSendResponse(
1156         std::chrono::microseconds(0), error, interrupt, done);
1157     if (result == PacketResult::ErrorReplyTimeout)
1158       break; // No more packets in the queue
1159 
1160     if ((result != PacketResult::Success)) {
1161       LLDB_LOGF(log,
1162                 "GDBRemoteCommunicationServerLLGS::%s processing a packet "
1163                 "failed: %s",
1164                 __FUNCTION__, error.AsCString());
1165       m_mainloop.RequestTermination();
1166       break;
1167     }
1168   }
1169 }
1170 
1171 Status GDBRemoteCommunicationServerLLGS::InitializeConnection(
1172     std::unique_ptr<Connection> connection) {
1173   IOObjectSP read_object_sp = connection->GetReadObject();
1174   GDBRemoteCommunicationServer::SetConnection(std::move(connection));
1175 
1176   Status error;
1177   m_network_handle_up = m_mainloop.RegisterReadObject(
1178       read_object_sp, [this](MainLoopBase &) { DataAvailableCallback(); },
1179       error);
1180   return error;
1181 }
1182 
1183 GDBRemoteCommunication::PacketResult
1184 GDBRemoteCommunicationServerLLGS::SendONotification(const char *buffer,
1185                                                     uint32_t len) {
1186   if ((buffer == nullptr) || (len == 0)) {
1187     // Nothing to send.
1188     return PacketResult::Success;
1189   }
1190 
1191   StreamString response;
1192   response.PutChar('O');
1193   response.PutBytesAsRawHex8(buffer, len);
1194 
1195   return SendPacketNoLock(response.GetString());
1196 }
1197 
1198 Status GDBRemoteCommunicationServerLLGS::SetSTDIOFileDescriptor(int fd) {
1199   Status error;
1200 
1201   // Set up the reading/handling of process I/O
1202   std::unique_ptr<ConnectionFileDescriptor> conn_up(
1203       new ConnectionFileDescriptor(fd, true));
1204   if (!conn_up) {
1205     error.SetErrorString("failed to create ConnectionFileDescriptor");
1206     return error;
1207   }
1208 
1209   m_stdio_communication.SetCloseOnEOF(false);
1210   m_stdio_communication.SetConnection(std::move(conn_up));
1211   if (!m_stdio_communication.IsConnected()) {
1212     error.SetErrorString(
1213         "failed to set connection for inferior I/O communication");
1214     return error;
1215   }
1216 
1217   return Status();
1218 }
1219 
1220 void GDBRemoteCommunicationServerLLGS::StartSTDIOForwarding() {
1221   // Don't forward if not connected (e.g. when attaching).
1222   if (!m_stdio_communication.IsConnected())
1223     return;
1224 
1225   Status error;
1226   assert(!m_stdio_handle_up);
1227   m_stdio_handle_up = m_mainloop.RegisterReadObject(
1228       m_stdio_communication.GetConnection()->GetReadObject(),
1229       [this](MainLoopBase &) { SendProcessOutput(); }, error);
1230 
1231   if (!m_stdio_handle_up) {
1232     // Not much we can do about the failure. Log it and continue without
1233     // forwarding.
1234     if (Log *log = GetLog(LLDBLog::Process))
1235       LLDB_LOG(log, "Failed to set up stdio forwarding: {0}", error);
1236   }
1237 }
1238 
1239 void GDBRemoteCommunicationServerLLGS::StopSTDIOForwarding() {
1240   m_stdio_handle_up.reset();
1241 }
1242 
1243 void GDBRemoteCommunicationServerLLGS::SendProcessOutput() {
1244   char buffer[1024];
1245   ConnectionStatus status;
1246   Status error;
1247   while (true) {
1248     size_t bytes_read = m_stdio_communication.Read(
1249         buffer, sizeof buffer, std::chrono::microseconds(0), status, &error);
1250     switch (status) {
1251     case eConnectionStatusSuccess:
1252       SendONotification(buffer, bytes_read);
1253       break;
1254     case eConnectionStatusLostConnection:
1255     case eConnectionStatusEndOfFile:
1256     case eConnectionStatusError:
1257     case eConnectionStatusNoConnection:
1258       if (Log *log = GetLog(LLDBLog::Process))
1259         LLDB_LOGF(log,
1260                   "GDBRemoteCommunicationServerLLGS::%s Stopping stdio "
1261                   "forwarding as communication returned status %d (error: "
1262                   "%s)",
1263                   __FUNCTION__, status, error.AsCString());
1264       m_stdio_handle_up.reset();
1265       return;
1266 
1267     case eConnectionStatusInterrupted:
1268     case eConnectionStatusTimedOut:
1269       return;
1270     }
1271   }
1272 }
1273 
1274 GDBRemoteCommunication::PacketResult
1275 GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceSupported(
1276     StringExtractorGDBRemote &packet) {
1277 
1278   // Fail if we don't have a current process.
1279   if (!m_current_process ||
1280       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1281     return SendErrorResponse(Status("Process not running."));
1282 
1283   return SendJSONResponse(m_current_process->TraceSupported());
1284 }
1285 
1286 GDBRemoteCommunication::PacketResult
1287 GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceStop(
1288     StringExtractorGDBRemote &packet) {
1289   // Fail if we don't have a current process.
1290   if (!m_current_process ||
1291       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1292     return SendErrorResponse(Status("Process not running."));
1293 
1294   packet.ConsumeFront("jLLDBTraceStop:");
1295   Expected<TraceStopRequest> stop_request =
1296       json::parse<TraceStopRequest>(packet.Peek(), "TraceStopRequest");
1297   if (!stop_request)
1298     return SendErrorResponse(stop_request.takeError());
1299 
1300   if (Error err = m_current_process->TraceStop(*stop_request))
1301     return SendErrorResponse(std::move(err));
1302 
1303   return SendOKResponse();
1304 }
1305 
1306 GDBRemoteCommunication::PacketResult
1307 GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceStart(
1308     StringExtractorGDBRemote &packet) {
1309 
1310   // Fail if we don't have a current process.
1311   if (!m_current_process ||
1312       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1313     return SendErrorResponse(Status("Process not running."));
1314 
1315   packet.ConsumeFront("jLLDBTraceStart:");
1316   Expected<TraceStartRequest> request =
1317       json::parse<TraceStartRequest>(packet.Peek(), "TraceStartRequest");
1318   if (!request)
1319     return SendErrorResponse(request.takeError());
1320 
1321   if (Error err = m_current_process->TraceStart(packet.Peek(), request->type))
1322     return SendErrorResponse(std::move(err));
1323 
1324   return SendOKResponse();
1325 }
1326 
1327 GDBRemoteCommunication::PacketResult
1328 GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceGetState(
1329     StringExtractorGDBRemote &packet) {
1330 
1331   // Fail if we don't have a current process.
1332   if (!m_current_process ||
1333       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1334     return SendErrorResponse(Status("Process not running."));
1335 
1336   packet.ConsumeFront("jLLDBTraceGetState:");
1337   Expected<TraceGetStateRequest> request =
1338       json::parse<TraceGetStateRequest>(packet.Peek(), "TraceGetStateRequest");
1339   if (!request)
1340     return SendErrorResponse(request.takeError());
1341 
1342   return SendJSONResponse(m_current_process->TraceGetState(request->type));
1343 }
1344 
1345 GDBRemoteCommunication::PacketResult
1346 GDBRemoteCommunicationServerLLGS::Handle_jLLDBTraceGetBinaryData(
1347     StringExtractorGDBRemote &packet) {
1348 
1349   // Fail if we don't have a current process.
1350   if (!m_current_process ||
1351       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1352     return SendErrorResponse(Status("Process not running."));
1353 
1354   packet.ConsumeFront("jLLDBTraceGetBinaryData:");
1355   llvm::Expected<TraceGetBinaryDataRequest> request =
1356       llvm::json::parse<TraceGetBinaryDataRequest>(packet.Peek(),
1357                                                    "TraceGetBinaryDataRequest");
1358   if (!request)
1359     return SendErrorResponse(Status(request.takeError()));
1360 
1361   if (Expected<std::vector<uint8_t>> bytes =
1362           m_current_process->TraceGetBinaryData(*request)) {
1363     StreamGDBRemote response;
1364     response.PutEscapedBytes(bytes->data(), bytes->size());
1365     return SendPacketNoLock(response.GetString());
1366   } else
1367     return SendErrorResponse(bytes.takeError());
1368 }
1369 
1370 GDBRemoteCommunication::PacketResult
1371 GDBRemoteCommunicationServerLLGS::Handle_qProcessInfo(
1372     StringExtractorGDBRemote &packet) {
1373   // Fail if we don't have a current process.
1374   if (!m_current_process ||
1375       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1376     return SendErrorResponse(68);
1377 
1378   lldb::pid_t pid = m_current_process->GetID();
1379 
1380   if (pid == LLDB_INVALID_PROCESS_ID)
1381     return SendErrorResponse(1);
1382 
1383   ProcessInstanceInfo proc_info;
1384   if (!Host::GetProcessInfo(pid, proc_info))
1385     return SendErrorResponse(1);
1386 
1387   StreamString response;
1388   CreateProcessInfoResponse_DebugServerStyle(proc_info, response);
1389   return SendPacketNoLock(response.GetString());
1390 }
1391 
1392 GDBRemoteCommunication::PacketResult
1393 GDBRemoteCommunicationServerLLGS::Handle_qC(StringExtractorGDBRemote &packet) {
1394   // Fail if we don't have a current process.
1395   if (!m_current_process ||
1396       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1397     return SendErrorResponse(68);
1398 
1399   // Make sure we set the current thread so g and p packets return the data the
1400   // gdb will expect.
1401   lldb::tid_t tid = m_current_process->GetCurrentThreadID();
1402   SetCurrentThreadID(tid);
1403 
1404   NativeThreadProtocol *thread = m_current_process->GetCurrentThread();
1405   if (!thread)
1406     return SendErrorResponse(69);
1407 
1408   StreamString response;
1409   response.PutCString("QC");
1410   AppendThreadIDToResponse(response, m_current_process->GetID(),
1411                            thread->GetID());
1412 
1413   return SendPacketNoLock(response.GetString());
1414 }
1415 
1416 GDBRemoteCommunication::PacketResult
1417 GDBRemoteCommunicationServerLLGS::Handle_k(StringExtractorGDBRemote &packet) {
1418   Log *log = GetLog(LLDBLog::Process);
1419 
1420   StopSTDIOForwarding();
1421 
1422   if (m_debugged_processes.empty()) {
1423     LLDB_LOG(log, "No debugged process found.");
1424     return PacketResult::Success;
1425   }
1426 
1427   for (auto it = m_debugged_processes.begin(); it != m_debugged_processes.end();
1428        ++it) {
1429     LLDB_LOG(log, "Killing process {0}", it->first);
1430     Status error = it->second.process_up->Kill();
1431     if (error.Fail())
1432       LLDB_LOG(log, "Failed to kill debugged process {0}: {1}", it->first,
1433                error);
1434   }
1435 
1436   // The response to kill packet is undefined per the spec.  LLDB
1437   // follows the same rules as for continue packets, i.e. no response
1438   // in all-stop mode, and "OK" in non-stop mode; in both cases this
1439   // is followed by the actual stop reason.
1440   return SendContinueSuccessResponse();
1441 }
1442 
1443 GDBRemoteCommunication::PacketResult
1444 GDBRemoteCommunicationServerLLGS::Handle_vKill(
1445     StringExtractorGDBRemote &packet) {
1446   StopSTDIOForwarding();
1447 
1448   packet.SetFilePos(6); // vKill;
1449   uint32_t pid = packet.GetU32(LLDB_INVALID_PROCESS_ID, 16);
1450   if (pid == LLDB_INVALID_PROCESS_ID)
1451     return SendIllFormedResponse(packet,
1452                                  "vKill failed to parse the process id");
1453 
1454   auto it = m_debugged_processes.find(pid);
1455   if (it == m_debugged_processes.end())
1456     return SendErrorResponse(42);
1457 
1458   Status error = it->second.process_up->Kill();
1459   if (error.Fail())
1460     return SendErrorResponse(error.ToError());
1461 
1462   // OK response is sent when the process dies.
1463   it->second.flags |= DebuggedProcess::Flag::vkilled;
1464   return PacketResult::Success;
1465 }
1466 
1467 GDBRemoteCommunication::PacketResult
1468 GDBRemoteCommunicationServerLLGS::Handle_QSetDisableASLR(
1469     StringExtractorGDBRemote &packet) {
1470   packet.SetFilePos(::strlen("QSetDisableASLR:"));
1471   if (packet.GetU32(0))
1472     m_process_launch_info.GetFlags().Set(eLaunchFlagDisableASLR);
1473   else
1474     m_process_launch_info.GetFlags().Clear(eLaunchFlagDisableASLR);
1475   return SendOKResponse();
1476 }
1477 
1478 GDBRemoteCommunication::PacketResult
1479 GDBRemoteCommunicationServerLLGS::Handle_QSetWorkingDir(
1480     StringExtractorGDBRemote &packet) {
1481   packet.SetFilePos(::strlen("QSetWorkingDir:"));
1482   std::string path;
1483   packet.GetHexByteString(path);
1484   m_process_launch_info.SetWorkingDirectory(FileSpec(path));
1485   return SendOKResponse();
1486 }
1487 
1488 GDBRemoteCommunication::PacketResult
1489 GDBRemoteCommunicationServerLLGS::Handle_qGetWorkingDir(
1490     StringExtractorGDBRemote &packet) {
1491   FileSpec working_dir{m_process_launch_info.GetWorkingDirectory()};
1492   if (working_dir) {
1493     StreamString response;
1494     response.PutStringAsRawHex8(working_dir.GetCString());
1495     return SendPacketNoLock(response.GetString());
1496   }
1497 
1498   return SendErrorResponse(14);
1499 }
1500 
1501 GDBRemoteCommunication::PacketResult
1502 GDBRemoteCommunicationServerLLGS::Handle_QThreadSuffixSupported(
1503     StringExtractorGDBRemote &packet) {
1504   m_thread_suffix_supported = true;
1505   return SendOKResponse();
1506 }
1507 
1508 GDBRemoteCommunication::PacketResult
1509 GDBRemoteCommunicationServerLLGS::Handle_QListThreadsInStopReply(
1510     StringExtractorGDBRemote &packet) {
1511   m_list_threads_in_stop_reply = true;
1512   return SendOKResponse();
1513 }
1514 
1515 GDBRemoteCommunication::PacketResult
1516 GDBRemoteCommunicationServerLLGS::ResumeProcess(
1517     NativeProcessProtocol &process, const ResumeActionList &actions) {
1518   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
1519 
1520   // In non-stop protocol mode, the process could be running already.
1521   // We do not support resuming threads independently, so just error out.
1522   if (!process.CanResume()) {
1523     LLDB_LOG(log, "process {0} cannot be resumed (state={1})", process.GetID(),
1524              process.GetState());
1525     return SendErrorResponse(0x37);
1526   }
1527 
1528   Status error = process.Resume(actions);
1529   if (error.Fail()) {
1530     LLDB_LOG(log, "process {0} failed to resume: {1}", process.GetID(), error);
1531     return SendErrorResponse(GDBRemoteServerError::eErrorResume);
1532   }
1533 
1534   LLDB_LOG(log, "process {0} resumed", process.GetID());
1535 
1536   return PacketResult::Success;
1537 }
1538 
1539 GDBRemoteCommunication::PacketResult
1540 GDBRemoteCommunicationServerLLGS::Handle_C(StringExtractorGDBRemote &packet) {
1541   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
1542   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s called", __FUNCTION__);
1543 
1544   // Ensure we have a native process.
1545   if (!m_continue_process) {
1546     LLDB_LOGF(log,
1547               "GDBRemoteCommunicationServerLLGS::%s no debugged process "
1548               "shared pointer",
1549               __FUNCTION__);
1550     return SendErrorResponse(0x36);
1551   }
1552 
1553   // Pull out the signal number.
1554   packet.SetFilePos(::strlen("C"));
1555   if (packet.GetBytesLeft() < 1) {
1556     // Shouldn't be using a C without a signal.
1557     return SendIllFormedResponse(packet, "C packet specified without signal.");
1558   }
1559   const uint32_t signo =
1560       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
1561   if (signo == std::numeric_limits<uint32_t>::max())
1562     return SendIllFormedResponse(packet, "failed to parse signal number");
1563 
1564   // Handle optional continue address.
1565   if (packet.GetBytesLeft() > 0) {
1566     // FIXME add continue at address support for $C{signo}[;{continue-address}].
1567     if (*packet.Peek() == ';')
1568       return SendUnimplementedResponse(packet.GetStringRef().data());
1569     else
1570       return SendIllFormedResponse(
1571           packet, "unexpected content after $C{signal-number}");
1572   }
1573 
1574   // In non-stop protocol mode, the process could be running already.
1575   // We do not support resuming threads independently, so just error out.
1576   if (!m_continue_process->CanResume()) {
1577     LLDB_LOG(log, "process cannot be resumed (state={0})",
1578              m_continue_process->GetState());
1579     return SendErrorResponse(0x37);
1580   }
1581 
1582   ResumeActionList resume_actions(StateType::eStateRunning,
1583                                   LLDB_INVALID_SIGNAL_NUMBER);
1584   Status error;
1585 
1586   // We have two branches: what to do if a continue thread is specified (in
1587   // which case we target sending the signal to that thread), or when we don't
1588   // have a continue thread set (in which case we send a signal to the
1589   // process).
1590 
1591   // TODO discuss with Greg Clayton, make sure this makes sense.
1592 
1593   lldb::tid_t signal_tid = GetContinueThreadID();
1594   if (signal_tid != LLDB_INVALID_THREAD_ID) {
1595     // The resume action for the continue thread (or all threads if a continue
1596     // thread is not set).
1597     ResumeAction action = {GetContinueThreadID(), StateType::eStateRunning,
1598                            static_cast<int>(signo)};
1599 
1600     // Add the action for the continue thread (or all threads when the continue
1601     // thread isn't present).
1602     resume_actions.Append(action);
1603   } else {
1604     // Send the signal to the process since we weren't targeting a specific
1605     // continue thread with the signal.
1606     error = m_continue_process->Signal(signo);
1607     if (error.Fail()) {
1608       LLDB_LOG(log, "failed to send signal for process {0}: {1}",
1609                m_continue_process->GetID(), error);
1610 
1611       return SendErrorResponse(0x52);
1612     }
1613   }
1614 
1615   // NB: this checks CanResume() twice but using a single code path for
1616   // resuming still seems worth it.
1617   PacketResult resume_res = ResumeProcess(*m_continue_process, resume_actions);
1618   if (resume_res != PacketResult::Success)
1619     return resume_res;
1620 
1621   // Don't send an "OK" packet, except in non-stop mode;
1622   // otherwise, the response is the stopped/exited message.
1623   return SendContinueSuccessResponse();
1624 }
1625 
1626 GDBRemoteCommunication::PacketResult
1627 GDBRemoteCommunicationServerLLGS::Handle_c(StringExtractorGDBRemote &packet) {
1628   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
1629   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s called", __FUNCTION__);
1630 
1631   packet.SetFilePos(packet.GetFilePos() + ::strlen("c"));
1632 
1633   // For now just support all continue.
1634   const bool has_continue_address = (packet.GetBytesLeft() > 0);
1635   if (has_continue_address) {
1636     LLDB_LOG(log, "not implemented for c[address] variant [{0} remains]",
1637              packet.Peek());
1638     return SendUnimplementedResponse(packet.GetStringRef().data());
1639   }
1640 
1641   // Ensure we have a native process.
1642   if (!m_continue_process) {
1643     LLDB_LOGF(log,
1644               "GDBRemoteCommunicationServerLLGS::%s no debugged process "
1645               "shared pointer",
1646               __FUNCTION__);
1647     return SendErrorResponse(0x36);
1648   }
1649 
1650   // Build the ResumeActionList
1651   ResumeActionList actions(StateType::eStateRunning,
1652                            LLDB_INVALID_SIGNAL_NUMBER);
1653 
1654   PacketResult resume_res = ResumeProcess(*m_continue_process, actions);
1655   if (resume_res != PacketResult::Success)
1656     return resume_res;
1657 
1658   return SendContinueSuccessResponse();
1659 }
1660 
1661 GDBRemoteCommunication::PacketResult
1662 GDBRemoteCommunicationServerLLGS::Handle_vCont_actions(
1663     StringExtractorGDBRemote &packet) {
1664   StreamString response;
1665   response.Printf("vCont;c;C;s;S;t");
1666 
1667   return SendPacketNoLock(response.GetString());
1668 }
1669 
1670 static bool ResumeActionListStopsAllThreads(ResumeActionList &actions) {
1671   // We're doing a stop-all if and only if our only action is a "t" for all
1672   // threads.
1673   if (const ResumeAction *default_action =
1674           actions.GetActionForThread(LLDB_INVALID_THREAD_ID, false)) {
1675     if (default_action->state == eStateSuspended && actions.GetSize() == 1)
1676       return true;
1677   }
1678 
1679   return false;
1680 }
1681 
1682 GDBRemoteCommunication::PacketResult
1683 GDBRemoteCommunicationServerLLGS::Handle_vCont(
1684     StringExtractorGDBRemote &packet) {
1685   Log *log = GetLog(LLDBLog::Process);
1686   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s handling vCont packet",
1687             __FUNCTION__);
1688 
1689   packet.SetFilePos(::strlen("vCont"));
1690 
1691   if (packet.GetBytesLeft() == 0) {
1692     LLDB_LOGF(log,
1693               "GDBRemoteCommunicationServerLLGS::%s missing action from "
1694               "vCont package",
1695               __FUNCTION__);
1696     return SendIllFormedResponse(packet, "Missing action from vCont package");
1697   }
1698 
1699   if (::strcmp(packet.Peek(), ";s") == 0) {
1700     // Move past the ';', then do a simple 's'.
1701     packet.SetFilePos(packet.GetFilePos() + 1);
1702     return Handle_s(packet);
1703   }
1704 
1705   std::unordered_map<lldb::pid_t, ResumeActionList> thread_actions;
1706 
1707   while (packet.GetBytesLeft() && *packet.Peek() == ';') {
1708     // Skip the semi-colon.
1709     packet.GetChar();
1710 
1711     // Build up the thread action.
1712     ResumeAction thread_action;
1713     thread_action.tid = LLDB_INVALID_THREAD_ID;
1714     thread_action.state = eStateInvalid;
1715     thread_action.signal = LLDB_INVALID_SIGNAL_NUMBER;
1716 
1717     const char action = packet.GetChar();
1718     switch (action) {
1719     case 'C':
1720       thread_action.signal = packet.GetHexMaxU32(false, 0);
1721       if (thread_action.signal == 0)
1722         return SendIllFormedResponse(
1723             packet, "Could not parse signal in vCont packet C action");
1724       LLVM_FALLTHROUGH;
1725 
1726     case 'c':
1727       // Continue
1728       thread_action.state = eStateRunning;
1729       break;
1730 
1731     case 'S':
1732       thread_action.signal = packet.GetHexMaxU32(false, 0);
1733       if (thread_action.signal == 0)
1734         return SendIllFormedResponse(
1735             packet, "Could not parse signal in vCont packet S action");
1736       LLVM_FALLTHROUGH;
1737 
1738     case 's':
1739       // Step
1740       thread_action.state = eStateStepping;
1741       break;
1742 
1743     case 't':
1744       // Stop
1745       thread_action.state = eStateSuspended;
1746       break;
1747 
1748     default:
1749       return SendIllFormedResponse(packet, "Unsupported vCont action");
1750       break;
1751     }
1752 
1753     lldb::pid_t pid = StringExtractorGDBRemote::AllProcesses;
1754     lldb::tid_t tid = StringExtractorGDBRemote::AllThreads;
1755 
1756     // Parse out optional :{thread-id} value.
1757     if (packet.GetBytesLeft() && (*packet.Peek() == ':')) {
1758       // Consume the separator.
1759       packet.GetChar();
1760 
1761       auto pid_tid = packet.GetPidTid(StringExtractorGDBRemote::AllProcesses);
1762       if (!pid_tid)
1763         return SendIllFormedResponse(packet, "Malformed thread-id");
1764 
1765       pid = pid_tid->first;
1766       tid = pid_tid->second;
1767     }
1768 
1769     if (thread_action.state == eStateSuspended &&
1770         tid != StringExtractorGDBRemote::AllThreads) {
1771       return SendIllFormedResponse(
1772           packet, "'t' action not supported for individual threads");
1773     }
1774 
1775     if (pid == StringExtractorGDBRemote::AllProcesses) {
1776       if (m_debugged_processes.size() > 1)
1777         return SendIllFormedResponse(
1778             packet, "Resuming multiple processes not supported yet");
1779       if (!m_continue_process) {
1780         LLDB_LOG(log, "no debugged process");
1781         return SendErrorResponse(0x36);
1782       }
1783       pid = m_continue_process->GetID();
1784     }
1785 
1786     if (tid == StringExtractorGDBRemote::AllThreads)
1787       tid = LLDB_INVALID_THREAD_ID;
1788 
1789     thread_action.tid = tid;
1790 
1791     thread_actions[pid].Append(thread_action);
1792   }
1793 
1794   assert(thread_actions.size() >= 1);
1795   if (thread_actions.size() > 1)
1796     return SendIllFormedResponse(
1797         packet, "Resuming multiple processes not supported yet");
1798 
1799   for (std::pair<lldb::pid_t, ResumeActionList> x : thread_actions) {
1800     auto process_it = m_debugged_processes.find(x.first);
1801     if (process_it == m_debugged_processes.end()) {
1802       LLDB_LOG(log, "vCont failed for process {0}: process not debugged",
1803                x.first);
1804       return SendErrorResponse(GDBRemoteServerError::eErrorResume);
1805     }
1806 
1807     // There are four possible scenarios here.  These are:
1808     // 1. vCont on a stopped process that resumes at least one thread.
1809     //    In this case, we call Resume().
1810     // 2. vCont on a stopped process that leaves all threads suspended.
1811     //    A no-op.
1812     // 3. vCont on a running process that requests suspending all
1813     //    running threads.  In this case, we call Interrupt().
1814     // 4. vCont on a running process that requests suspending a subset
1815     //    of running threads or resuming a subset of suspended threads.
1816     //    Since we do not support full nonstop mode, this is unsupported
1817     //    and we return an error.
1818 
1819     assert(process_it->second.process_up);
1820     if (ResumeActionListStopsAllThreads(x.second)) {
1821       if (process_it->second.process_up->IsRunning()) {
1822         assert(m_non_stop);
1823 
1824         Status error = process_it->second.process_up->Interrupt();
1825         if (error.Fail()) {
1826           LLDB_LOG(log, "vCont failed to halt process {0}: {1}", x.first,
1827                    error);
1828           return SendErrorResponse(GDBRemoteServerError::eErrorResume);
1829         }
1830 
1831         LLDB_LOG(log, "halted process {0}", x.first);
1832 
1833         // hack to avoid enabling stdio forwarding after stop
1834         // TODO: remove this when we improve stdio forwarding for nonstop
1835         assert(thread_actions.size() == 1);
1836         return SendOKResponse();
1837       }
1838     } else {
1839       PacketResult resume_res =
1840           ResumeProcess(*process_it->second.process_up, x.second);
1841       if (resume_res != PacketResult::Success)
1842         return resume_res;
1843     }
1844   }
1845 
1846   return SendContinueSuccessResponse();
1847 }
1848 
1849 void GDBRemoteCommunicationServerLLGS::SetCurrentThreadID(lldb::tid_t tid) {
1850   Log *log = GetLog(LLDBLog::Thread);
1851   LLDB_LOG(log, "setting current thread id to {0}", tid);
1852 
1853   m_current_tid = tid;
1854   if (m_current_process)
1855     m_current_process->SetCurrentThreadID(m_current_tid);
1856 }
1857 
1858 void GDBRemoteCommunicationServerLLGS::SetContinueThreadID(lldb::tid_t tid) {
1859   Log *log = GetLog(LLDBLog::Thread);
1860   LLDB_LOG(log, "setting continue thread id to {0}", tid);
1861 
1862   m_continue_tid = tid;
1863 }
1864 
1865 GDBRemoteCommunication::PacketResult
1866 GDBRemoteCommunicationServerLLGS::Handle_stop_reason(
1867     StringExtractorGDBRemote &packet) {
1868   // Handle the $? gdbremote command.
1869 
1870   if (m_non_stop) {
1871     // Clear the notification queue first, except for pending exit
1872     // notifications.
1873     llvm::erase_if(m_stop_notification_queue, [](const std::string &x) {
1874       return x.front() != 'W' && x.front() != 'X';
1875     });
1876 
1877     if (m_current_process) {
1878       // Queue stop reply packets for all active threads.  Start with
1879       // the current thread (for clients that don't actually support multiple
1880       // stop reasons).
1881       NativeThreadProtocol *thread = m_current_process->GetCurrentThread();
1882       if (thread)
1883         m_stop_notification_queue.push_back(
1884             PrepareStopReplyPacketForThread(*thread).GetString().str());
1885       EnqueueStopReplyPackets(thread ? thread->GetID()
1886                                      : LLDB_INVALID_THREAD_ID);
1887     }
1888 
1889     // If the notification queue is empty (i.e. everything is running), send OK.
1890     if (m_stop_notification_queue.empty())
1891       return SendOKResponse();
1892 
1893     // Send the first item from the new notification queue synchronously.
1894     return SendPacketNoLock(m_stop_notification_queue.front());
1895   }
1896 
1897   // If no process, indicate error
1898   if (!m_current_process)
1899     return SendErrorResponse(02);
1900 
1901   return SendStopReasonForState(*m_current_process,
1902                                 m_current_process->GetState(),
1903                                 /*force_synchronous=*/true);
1904 }
1905 
1906 GDBRemoteCommunication::PacketResult
1907 GDBRemoteCommunicationServerLLGS::SendStopReasonForState(
1908     NativeProcessProtocol &process, lldb::StateType process_state,
1909     bool force_synchronous) {
1910   Log *log = GetLog(LLDBLog::Process);
1911 
1912   switch (process_state) {
1913   case eStateAttaching:
1914   case eStateLaunching:
1915   case eStateRunning:
1916   case eStateStepping:
1917   case eStateDetached:
1918     // NOTE: gdb protocol doc looks like it should return $OK
1919     // when everything is running (i.e. no stopped result).
1920     return PacketResult::Success; // Ignore
1921 
1922   case eStateSuspended:
1923   case eStateStopped:
1924   case eStateCrashed: {
1925     lldb::tid_t tid = process.GetCurrentThreadID();
1926     // Make sure we set the current thread so g and p packets return the data
1927     // the gdb will expect.
1928     SetCurrentThreadID(tid);
1929     return SendStopReplyPacketForThread(process, tid, force_synchronous);
1930   }
1931 
1932   case eStateInvalid:
1933   case eStateUnloaded:
1934   case eStateExited:
1935     return SendWResponse(&process);
1936 
1937   default:
1938     LLDB_LOG(log, "pid {0}, current state reporting not handled: {1}",
1939              process.GetID(), process_state);
1940     break;
1941   }
1942 
1943   return SendErrorResponse(0);
1944 }
1945 
1946 GDBRemoteCommunication::PacketResult
1947 GDBRemoteCommunicationServerLLGS::Handle_qRegisterInfo(
1948     StringExtractorGDBRemote &packet) {
1949   // Fail if we don't have a current process.
1950   if (!m_current_process ||
1951       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1952     return SendErrorResponse(68);
1953 
1954   // Ensure we have a thread.
1955   NativeThreadProtocol *thread = m_current_process->GetThreadAtIndex(0);
1956   if (!thread)
1957     return SendErrorResponse(69);
1958 
1959   // Get the register context for the first thread.
1960   NativeRegisterContext &reg_context = thread->GetRegisterContext();
1961 
1962   // Parse out the register number from the request.
1963   packet.SetFilePos(strlen("qRegisterInfo"));
1964   const uint32_t reg_index =
1965       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
1966   if (reg_index == std::numeric_limits<uint32_t>::max())
1967     return SendErrorResponse(69);
1968 
1969   // Return the end of registers response if we've iterated one past the end of
1970   // the register set.
1971   if (reg_index >= reg_context.GetUserRegisterCount())
1972     return SendErrorResponse(69);
1973 
1974   const RegisterInfo *reg_info = reg_context.GetRegisterInfoAtIndex(reg_index);
1975   if (!reg_info)
1976     return SendErrorResponse(69);
1977 
1978   // Build the reginfos response.
1979   StreamGDBRemote response;
1980 
1981   response.PutCString("name:");
1982   response.PutCString(reg_info->name);
1983   response.PutChar(';');
1984 
1985   if (reg_info->alt_name && reg_info->alt_name[0]) {
1986     response.PutCString("alt-name:");
1987     response.PutCString(reg_info->alt_name);
1988     response.PutChar(';');
1989   }
1990 
1991   response.Printf("bitsize:%" PRIu32 ";", reg_info->byte_size * 8);
1992 
1993   if (!reg_context.RegisterOffsetIsDynamic())
1994     response.Printf("offset:%" PRIu32 ";", reg_info->byte_offset);
1995 
1996   llvm::StringRef encoding = GetEncodingNameOrEmpty(*reg_info);
1997   if (!encoding.empty())
1998     response << "encoding:" << encoding << ';';
1999 
2000   llvm::StringRef format = GetFormatNameOrEmpty(*reg_info);
2001   if (!format.empty())
2002     response << "format:" << format << ';';
2003 
2004   const char *const register_set_name =
2005       reg_context.GetRegisterSetNameForRegisterAtIndex(reg_index);
2006   if (register_set_name)
2007     response << "set:" << register_set_name << ';';
2008 
2009   if (reg_info->kinds[RegisterKind::eRegisterKindEHFrame] !=
2010       LLDB_INVALID_REGNUM)
2011     response.Printf("ehframe:%" PRIu32 ";",
2012                     reg_info->kinds[RegisterKind::eRegisterKindEHFrame]);
2013 
2014   if (reg_info->kinds[RegisterKind::eRegisterKindDWARF] != LLDB_INVALID_REGNUM)
2015     response.Printf("dwarf:%" PRIu32 ";",
2016                     reg_info->kinds[RegisterKind::eRegisterKindDWARF]);
2017 
2018   llvm::StringRef kind_generic = GetKindGenericOrEmpty(*reg_info);
2019   if (!kind_generic.empty())
2020     response << "generic:" << kind_generic << ';';
2021 
2022   if (reg_info->value_regs && reg_info->value_regs[0] != LLDB_INVALID_REGNUM) {
2023     response.PutCString("container-regs:");
2024     CollectRegNums(reg_info->value_regs, response, true);
2025     response.PutChar(';');
2026   }
2027 
2028   if (reg_info->invalidate_regs && reg_info->invalidate_regs[0]) {
2029     response.PutCString("invalidate-regs:");
2030     CollectRegNums(reg_info->invalidate_regs, response, true);
2031     response.PutChar(';');
2032   }
2033 
2034   return SendPacketNoLock(response.GetString());
2035 }
2036 
2037 void GDBRemoteCommunicationServerLLGS::AddProcessThreads(
2038     StreamGDBRemote &response, NativeProcessProtocol &process, bool &had_any) {
2039   Log *log = GetLog(LLDBLog::Thread);
2040 
2041   lldb::pid_t pid = process.GetID();
2042   if (pid == LLDB_INVALID_PROCESS_ID)
2043     return;
2044 
2045   LLDB_LOG(log, "iterating over threads of process {0}", process.GetID());
2046   for (NativeThreadProtocol &thread : process.Threads()) {
2047     LLDB_LOG(log, "iterated thread tid={0}", thread.GetID());
2048     response.PutChar(had_any ? ',' : 'm');
2049     AppendThreadIDToResponse(response, pid, thread.GetID());
2050     had_any = true;
2051   }
2052 }
2053 
2054 GDBRemoteCommunication::PacketResult
2055 GDBRemoteCommunicationServerLLGS::Handle_qfThreadInfo(
2056     StringExtractorGDBRemote &packet) {
2057   assert(m_debugged_processes.size() == 1 ||
2058          bool(m_extensions_supported &
2059               NativeProcessProtocol::Extension::multiprocess));
2060 
2061   bool had_any = false;
2062   StreamGDBRemote response;
2063 
2064   for (auto &pid_ptr : m_debugged_processes)
2065     AddProcessThreads(response, *pid_ptr.second.process_up, had_any);
2066 
2067   if (!had_any)
2068     return SendOKResponse();
2069   return SendPacketNoLock(response.GetString());
2070 }
2071 
2072 GDBRemoteCommunication::PacketResult
2073 GDBRemoteCommunicationServerLLGS::Handle_qsThreadInfo(
2074     StringExtractorGDBRemote &packet) {
2075   // FIXME for now we return the full thread list in the initial packet and
2076   // always do nothing here.
2077   return SendPacketNoLock("l");
2078 }
2079 
2080 GDBRemoteCommunication::PacketResult
2081 GDBRemoteCommunicationServerLLGS::Handle_g(StringExtractorGDBRemote &packet) {
2082   Log *log = GetLog(LLDBLog::Thread);
2083 
2084   // Move past packet name.
2085   packet.SetFilePos(strlen("g"));
2086 
2087   // Get the thread to use.
2088   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
2089   if (!thread) {
2090     LLDB_LOG(log, "failed, no thread available");
2091     return SendErrorResponse(0x15);
2092   }
2093 
2094   // Get the thread's register context.
2095   NativeRegisterContext &reg_ctx = thread->GetRegisterContext();
2096 
2097   std::vector<uint8_t> regs_buffer;
2098   for (uint32_t reg_num = 0; reg_num < reg_ctx.GetUserRegisterCount();
2099        ++reg_num) {
2100     const RegisterInfo *reg_info = reg_ctx.GetRegisterInfoAtIndex(reg_num);
2101 
2102     if (reg_info == nullptr) {
2103       LLDB_LOG(log, "failed to get register info for register index {0}",
2104                reg_num);
2105       return SendErrorResponse(0x15);
2106     }
2107 
2108     if (reg_info->value_regs != nullptr)
2109       continue; // skip registers that are contained in other registers
2110 
2111     RegisterValue reg_value;
2112     Status error = reg_ctx.ReadRegister(reg_info, reg_value);
2113     if (error.Fail()) {
2114       LLDB_LOG(log, "failed to read register at index {0}", reg_num);
2115       return SendErrorResponse(0x15);
2116     }
2117 
2118     if (reg_info->byte_offset + reg_info->byte_size >= regs_buffer.size())
2119       // Resize the buffer to guarantee it can store the register offsetted
2120       // data.
2121       regs_buffer.resize(reg_info->byte_offset + reg_info->byte_size);
2122 
2123     // Copy the register offsetted data to the buffer.
2124     memcpy(regs_buffer.data() + reg_info->byte_offset, reg_value.GetBytes(),
2125            reg_info->byte_size);
2126   }
2127 
2128   // Write the response.
2129   StreamGDBRemote response;
2130   response.PutBytesAsRawHex8(regs_buffer.data(), regs_buffer.size());
2131 
2132   return SendPacketNoLock(response.GetString());
2133 }
2134 
2135 GDBRemoteCommunication::PacketResult
2136 GDBRemoteCommunicationServerLLGS::Handle_p(StringExtractorGDBRemote &packet) {
2137   Log *log = GetLog(LLDBLog::Thread);
2138 
2139   // Parse out the register number from the request.
2140   packet.SetFilePos(strlen("p"));
2141   const uint32_t reg_index =
2142       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
2143   if (reg_index == std::numeric_limits<uint32_t>::max()) {
2144     LLDB_LOGF(log,
2145               "GDBRemoteCommunicationServerLLGS::%s failed, could not "
2146               "parse register number from request \"%s\"",
2147               __FUNCTION__, packet.GetStringRef().data());
2148     return SendErrorResponse(0x15);
2149   }
2150 
2151   // Get the thread to use.
2152   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
2153   if (!thread) {
2154     LLDB_LOG(log, "failed, no thread available");
2155     return SendErrorResponse(0x15);
2156   }
2157 
2158   // Get the thread's register context.
2159   NativeRegisterContext &reg_context = thread->GetRegisterContext();
2160 
2161   // Return the end of registers response if we've iterated one past the end of
2162   // the register set.
2163   if (reg_index >= reg_context.GetUserRegisterCount()) {
2164     LLDB_LOGF(log,
2165               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2166               "register %" PRIu32 " beyond register count %" PRIu32,
2167               __FUNCTION__, reg_index, reg_context.GetUserRegisterCount());
2168     return SendErrorResponse(0x15);
2169   }
2170 
2171   const RegisterInfo *reg_info = reg_context.GetRegisterInfoAtIndex(reg_index);
2172   if (!reg_info) {
2173     LLDB_LOGF(log,
2174               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2175               "register %" PRIu32 " returned NULL",
2176               __FUNCTION__, reg_index);
2177     return SendErrorResponse(0x15);
2178   }
2179 
2180   // Build the reginfos response.
2181   StreamGDBRemote response;
2182 
2183   // Retrieve the value
2184   RegisterValue reg_value;
2185   Status error = reg_context.ReadRegister(reg_info, reg_value);
2186   if (error.Fail()) {
2187     LLDB_LOGF(log,
2188               "GDBRemoteCommunicationServerLLGS::%s failed, read of "
2189               "requested register %" PRIu32 " (%s) failed: %s",
2190               __FUNCTION__, reg_index, reg_info->name, error.AsCString());
2191     return SendErrorResponse(0x15);
2192   }
2193 
2194   const uint8_t *const data =
2195       static_cast<const uint8_t *>(reg_value.GetBytes());
2196   if (!data) {
2197     LLDB_LOGF(log,
2198               "GDBRemoteCommunicationServerLLGS::%s failed to get data "
2199               "bytes from requested register %" PRIu32,
2200               __FUNCTION__, reg_index);
2201     return SendErrorResponse(0x15);
2202   }
2203 
2204   // FIXME flip as needed to get data in big/little endian format for this host.
2205   for (uint32_t i = 0; i < reg_value.GetByteSize(); ++i)
2206     response.PutHex8(data[i]);
2207 
2208   return SendPacketNoLock(response.GetString());
2209 }
2210 
2211 GDBRemoteCommunication::PacketResult
2212 GDBRemoteCommunicationServerLLGS::Handle_P(StringExtractorGDBRemote &packet) {
2213   Log *log = GetLog(LLDBLog::Thread);
2214 
2215   // Ensure there is more content.
2216   if (packet.GetBytesLeft() < 1)
2217     return SendIllFormedResponse(packet, "Empty P packet");
2218 
2219   // Parse out the register number from the request.
2220   packet.SetFilePos(strlen("P"));
2221   const uint32_t reg_index =
2222       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
2223   if (reg_index == std::numeric_limits<uint32_t>::max()) {
2224     LLDB_LOGF(log,
2225               "GDBRemoteCommunicationServerLLGS::%s failed, could not "
2226               "parse register number from request \"%s\"",
2227               __FUNCTION__, packet.GetStringRef().data());
2228     return SendErrorResponse(0x29);
2229   }
2230 
2231   // Note debugserver would send an E30 here.
2232   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != '='))
2233     return SendIllFormedResponse(
2234         packet, "P packet missing '=' char after register number");
2235 
2236   // Parse out the value.
2237   uint8_t reg_bytes[RegisterValue::kMaxRegisterByteSize];
2238   size_t reg_size = packet.GetHexBytesAvail(reg_bytes);
2239 
2240   // Get the thread to use.
2241   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
2242   if (!thread) {
2243     LLDB_LOGF(log,
2244               "GDBRemoteCommunicationServerLLGS::%s failed, no thread "
2245               "available (thread index 0)",
2246               __FUNCTION__);
2247     return SendErrorResponse(0x28);
2248   }
2249 
2250   // Get the thread's register context.
2251   NativeRegisterContext &reg_context = thread->GetRegisterContext();
2252   const RegisterInfo *reg_info = reg_context.GetRegisterInfoAtIndex(reg_index);
2253   if (!reg_info) {
2254     LLDB_LOGF(log,
2255               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2256               "register %" PRIu32 " returned NULL",
2257               __FUNCTION__, reg_index);
2258     return SendErrorResponse(0x48);
2259   }
2260 
2261   // Return the end of registers response if we've iterated one past the end of
2262   // the register set.
2263   if (reg_index >= reg_context.GetUserRegisterCount()) {
2264     LLDB_LOGF(log,
2265               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2266               "register %" PRIu32 " beyond register count %" PRIu32,
2267               __FUNCTION__, reg_index, reg_context.GetUserRegisterCount());
2268     return SendErrorResponse(0x47);
2269   }
2270 
2271   if (reg_size != reg_info->byte_size)
2272     return SendIllFormedResponse(packet, "P packet register size is incorrect");
2273 
2274   // Build the reginfos response.
2275   StreamGDBRemote response;
2276 
2277   RegisterValue reg_value(makeArrayRef(reg_bytes, reg_size),
2278                           m_current_process->GetArchitecture().GetByteOrder());
2279   Status error = reg_context.WriteRegister(reg_info, reg_value);
2280   if (error.Fail()) {
2281     LLDB_LOGF(log,
2282               "GDBRemoteCommunicationServerLLGS::%s failed, write of "
2283               "requested register %" PRIu32 " (%s) failed: %s",
2284               __FUNCTION__, reg_index, reg_info->name, error.AsCString());
2285     return SendErrorResponse(0x32);
2286   }
2287 
2288   return SendOKResponse();
2289 }
2290 
2291 GDBRemoteCommunication::PacketResult
2292 GDBRemoteCommunicationServerLLGS::Handle_H(StringExtractorGDBRemote &packet) {
2293   Log *log = GetLog(LLDBLog::Thread);
2294 
2295   // Parse out which variant of $H is requested.
2296   packet.SetFilePos(strlen("H"));
2297   if (packet.GetBytesLeft() < 1) {
2298     LLDB_LOGF(log,
2299               "GDBRemoteCommunicationServerLLGS::%s failed, H command "
2300               "missing {g,c} variant",
2301               __FUNCTION__);
2302     return SendIllFormedResponse(packet, "H command missing {g,c} variant");
2303   }
2304 
2305   const char h_variant = packet.GetChar();
2306   NativeProcessProtocol *default_process;
2307   switch (h_variant) {
2308   case 'g':
2309     default_process = m_current_process;
2310     break;
2311 
2312   case 'c':
2313     default_process = m_continue_process;
2314     break;
2315 
2316   default:
2317     LLDB_LOGF(
2318         log,
2319         "GDBRemoteCommunicationServerLLGS::%s failed, invalid $H variant %c",
2320         __FUNCTION__, h_variant);
2321     return SendIllFormedResponse(packet,
2322                                  "H variant unsupported, should be c or g");
2323   }
2324 
2325   // Parse out the thread number.
2326   auto pid_tid = packet.GetPidTid(default_process ? default_process->GetID()
2327                                                   : LLDB_INVALID_PROCESS_ID);
2328   if (!pid_tid)
2329     return SendErrorResponse(llvm::make_error<StringError>(
2330         inconvertibleErrorCode(), "Malformed thread-id"));
2331 
2332   lldb::pid_t pid = pid_tid->first;
2333   lldb::tid_t tid = pid_tid->second;
2334 
2335   if (pid == StringExtractorGDBRemote::AllProcesses)
2336     return SendUnimplementedResponse("Selecting all processes not supported");
2337   if (pid == LLDB_INVALID_PROCESS_ID)
2338     return SendErrorResponse(llvm::make_error<StringError>(
2339         inconvertibleErrorCode(), "No current process and no PID provided"));
2340 
2341   // Check the process ID and find respective process instance.
2342   auto new_process_it = m_debugged_processes.find(pid);
2343   if (new_process_it == m_debugged_processes.end())
2344     return SendErrorResponse(llvm::make_error<StringError>(
2345         inconvertibleErrorCode(),
2346         llvm::formatv("No process with PID {0} debugged", pid)));
2347 
2348   // Ensure we have the given thread when not specifying -1 (all threads) or 0
2349   // (any thread).
2350   if (tid != LLDB_INVALID_THREAD_ID && tid != 0) {
2351     NativeThreadProtocol *thread =
2352         new_process_it->second.process_up->GetThreadByID(tid);
2353     if (!thread) {
2354       LLDB_LOGF(log,
2355                 "GDBRemoteCommunicationServerLLGS::%s failed, tid %" PRIu64
2356                 " not found",
2357                 __FUNCTION__, tid);
2358       return SendErrorResponse(0x15);
2359     }
2360   }
2361 
2362   // Now switch the given process and thread type.
2363   switch (h_variant) {
2364   case 'g':
2365     m_current_process = new_process_it->second.process_up.get();
2366     SetCurrentThreadID(tid);
2367     break;
2368 
2369   case 'c':
2370     m_continue_process = new_process_it->second.process_up.get();
2371     SetContinueThreadID(tid);
2372     break;
2373 
2374   default:
2375     assert(false && "unsupported $H variant - shouldn't get here");
2376     return SendIllFormedResponse(packet,
2377                                  "H variant unsupported, should be c or g");
2378   }
2379 
2380   return SendOKResponse();
2381 }
2382 
2383 GDBRemoteCommunication::PacketResult
2384 GDBRemoteCommunicationServerLLGS::Handle_I(StringExtractorGDBRemote &packet) {
2385   Log *log = GetLog(LLDBLog::Thread);
2386 
2387   // Fail if we don't have a current process.
2388   if (!m_current_process ||
2389       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2390     LLDB_LOGF(
2391         log,
2392         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2393         __FUNCTION__);
2394     return SendErrorResponse(0x15);
2395   }
2396 
2397   packet.SetFilePos(::strlen("I"));
2398   uint8_t tmp[4096];
2399   for (;;) {
2400     size_t read = packet.GetHexBytesAvail(tmp);
2401     if (read == 0) {
2402       break;
2403     }
2404     // write directly to stdin *this might block if stdin buffer is full*
2405     // TODO: enqueue this block in circular buffer and send window size to
2406     // remote host
2407     ConnectionStatus status;
2408     Status error;
2409     m_stdio_communication.Write(tmp, read, status, &error);
2410     if (error.Fail()) {
2411       return SendErrorResponse(0x15);
2412     }
2413   }
2414 
2415   return SendOKResponse();
2416 }
2417 
2418 GDBRemoteCommunication::PacketResult
2419 GDBRemoteCommunicationServerLLGS::Handle_interrupt(
2420     StringExtractorGDBRemote &packet) {
2421   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
2422 
2423   // Fail if we don't have a current process.
2424   if (!m_current_process ||
2425       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2426     LLDB_LOG(log, "failed, no process available");
2427     return SendErrorResponse(0x15);
2428   }
2429 
2430   // Interrupt the process.
2431   Status error = m_current_process->Interrupt();
2432   if (error.Fail()) {
2433     LLDB_LOG(log, "failed for process {0}: {1}", m_current_process->GetID(),
2434              error);
2435     return SendErrorResponse(GDBRemoteServerError::eErrorResume);
2436   }
2437 
2438   LLDB_LOG(log, "stopped process {0}", m_current_process->GetID());
2439 
2440   // No response required from stop all.
2441   return PacketResult::Success;
2442 }
2443 
2444 GDBRemoteCommunication::PacketResult
2445 GDBRemoteCommunicationServerLLGS::Handle_memory_read(
2446     StringExtractorGDBRemote &packet) {
2447   Log *log = GetLog(LLDBLog::Process);
2448 
2449   if (!m_current_process ||
2450       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2451     LLDB_LOGF(
2452         log,
2453         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2454         __FUNCTION__);
2455     return SendErrorResponse(0x15);
2456   }
2457 
2458   // Parse out the memory address.
2459   packet.SetFilePos(strlen("m"));
2460   if (packet.GetBytesLeft() < 1)
2461     return SendIllFormedResponse(packet, "Too short m packet");
2462 
2463   // Read the address.  Punting on validation.
2464   // FIXME replace with Hex U64 read with no default value that fails on failed
2465   // read.
2466   const lldb::addr_t read_addr = packet.GetHexMaxU64(false, 0);
2467 
2468   // Validate comma.
2469   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != ','))
2470     return SendIllFormedResponse(packet, "Comma sep missing in m packet");
2471 
2472   // Get # bytes to read.
2473   if (packet.GetBytesLeft() < 1)
2474     return SendIllFormedResponse(packet, "Length missing in m packet");
2475 
2476   const uint64_t byte_count = packet.GetHexMaxU64(false, 0);
2477   if (byte_count == 0) {
2478     LLDB_LOGF(log,
2479               "GDBRemoteCommunicationServerLLGS::%s nothing to read: "
2480               "zero-length packet",
2481               __FUNCTION__);
2482     return SendOKResponse();
2483   }
2484 
2485   // Allocate the response buffer.
2486   std::string buf(byte_count, '\0');
2487   if (buf.empty())
2488     return SendErrorResponse(0x78);
2489 
2490   // Retrieve the process memory.
2491   size_t bytes_read = 0;
2492   Status error = m_current_process->ReadMemoryWithoutTrap(
2493       read_addr, &buf[0], byte_count, bytes_read);
2494   if (error.Fail()) {
2495     LLDB_LOGF(log,
2496               "GDBRemoteCommunicationServerLLGS::%s pid %" PRIu64
2497               " mem 0x%" PRIx64 ": failed to read. Error: %s",
2498               __FUNCTION__, m_current_process->GetID(), read_addr,
2499               error.AsCString());
2500     return SendErrorResponse(0x08);
2501   }
2502 
2503   if (bytes_read == 0) {
2504     LLDB_LOGF(log,
2505               "GDBRemoteCommunicationServerLLGS::%s pid %" PRIu64
2506               " mem 0x%" PRIx64 ": read 0 of %" PRIu64 " requested bytes",
2507               __FUNCTION__, m_current_process->GetID(), read_addr, byte_count);
2508     return SendErrorResponse(0x08);
2509   }
2510 
2511   StreamGDBRemote response;
2512   packet.SetFilePos(0);
2513   char kind = packet.GetChar('?');
2514   if (kind == 'x')
2515     response.PutEscapedBytes(buf.data(), byte_count);
2516   else {
2517     assert(kind == 'm');
2518     for (size_t i = 0; i < bytes_read; ++i)
2519       response.PutHex8(buf[i]);
2520   }
2521 
2522   return SendPacketNoLock(response.GetString());
2523 }
2524 
2525 GDBRemoteCommunication::PacketResult
2526 GDBRemoteCommunicationServerLLGS::Handle__M(StringExtractorGDBRemote &packet) {
2527   Log *log = GetLog(LLDBLog::Process);
2528 
2529   if (!m_current_process ||
2530       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2531     LLDB_LOGF(
2532         log,
2533         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2534         __FUNCTION__);
2535     return SendErrorResponse(0x15);
2536   }
2537 
2538   // Parse out the memory address.
2539   packet.SetFilePos(strlen("_M"));
2540   if (packet.GetBytesLeft() < 1)
2541     return SendIllFormedResponse(packet, "Too short _M packet");
2542 
2543   const lldb::addr_t size = packet.GetHexMaxU64(false, LLDB_INVALID_ADDRESS);
2544   if (size == LLDB_INVALID_ADDRESS)
2545     return SendIllFormedResponse(packet, "Address not valid");
2546   if (packet.GetChar() != ',')
2547     return SendIllFormedResponse(packet, "Bad packet");
2548   Permissions perms = {};
2549   while (packet.GetBytesLeft() > 0) {
2550     switch (packet.GetChar()) {
2551     case 'r':
2552       perms |= ePermissionsReadable;
2553       break;
2554     case 'w':
2555       perms |= ePermissionsWritable;
2556       break;
2557     case 'x':
2558       perms |= ePermissionsExecutable;
2559       break;
2560     default:
2561       return SendIllFormedResponse(packet, "Bad permissions");
2562     }
2563   }
2564 
2565   llvm::Expected<addr_t> addr = m_current_process->AllocateMemory(size, perms);
2566   if (!addr)
2567     return SendErrorResponse(addr.takeError());
2568 
2569   StreamGDBRemote response;
2570   response.PutHex64(*addr);
2571   return SendPacketNoLock(response.GetString());
2572 }
2573 
2574 GDBRemoteCommunication::PacketResult
2575 GDBRemoteCommunicationServerLLGS::Handle__m(StringExtractorGDBRemote &packet) {
2576   Log *log = GetLog(LLDBLog::Process);
2577 
2578   if (!m_current_process ||
2579       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2580     LLDB_LOGF(
2581         log,
2582         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2583         __FUNCTION__);
2584     return SendErrorResponse(0x15);
2585   }
2586 
2587   // Parse out the memory address.
2588   packet.SetFilePos(strlen("_m"));
2589   if (packet.GetBytesLeft() < 1)
2590     return SendIllFormedResponse(packet, "Too short m packet");
2591 
2592   const lldb::addr_t addr = packet.GetHexMaxU64(false, LLDB_INVALID_ADDRESS);
2593   if (addr == LLDB_INVALID_ADDRESS)
2594     return SendIllFormedResponse(packet, "Address not valid");
2595 
2596   if (llvm::Error Err = m_current_process->DeallocateMemory(addr))
2597     return SendErrorResponse(std::move(Err));
2598 
2599   return SendOKResponse();
2600 }
2601 
2602 GDBRemoteCommunication::PacketResult
2603 GDBRemoteCommunicationServerLLGS::Handle_M(StringExtractorGDBRemote &packet) {
2604   Log *log = GetLog(LLDBLog::Process);
2605 
2606   if (!m_current_process ||
2607       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2608     LLDB_LOGF(
2609         log,
2610         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2611         __FUNCTION__);
2612     return SendErrorResponse(0x15);
2613   }
2614 
2615   // Parse out the memory address.
2616   packet.SetFilePos(strlen("M"));
2617   if (packet.GetBytesLeft() < 1)
2618     return SendIllFormedResponse(packet, "Too short M packet");
2619 
2620   // Read the address.  Punting on validation.
2621   // FIXME replace with Hex U64 read with no default value that fails on failed
2622   // read.
2623   const lldb::addr_t write_addr = packet.GetHexMaxU64(false, 0);
2624 
2625   // Validate comma.
2626   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != ','))
2627     return SendIllFormedResponse(packet, "Comma sep missing in M packet");
2628 
2629   // Get # bytes to read.
2630   if (packet.GetBytesLeft() < 1)
2631     return SendIllFormedResponse(packet, "Length missing in M packet");
2632 
2633   const uint64_t byte_count = packet.GetHexMaxU64(false, 0);
2634   if (byte_count == 0) {
2635     LLDB_LOG(log, "nothing to write: zero-length packet");
2636     return PacketResult::Success;
2637   }
2638 
2639   // Validate colon.
2640   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != ':'))
2641     return SendIllFormedResponse(
2642         packet, "Comma sep missing in M packet after byte length");
2643 
2644   // Allocate the conversion buffer.
2645   std::vector<uint8_t> buf(byte_count, 0);
2646   if (buf.empty())
2647     return SendErrorResponse(0x78);
2648 
2649   // Convert the hex memory write contents to bytes.
2650   StreamGDBRemote response;
2651   const uint64_t convert_count = packet.GetHexBytes(buf, 0);
2652   if (convert_count != byte_count) {
2653     LLDB_LOG(log,
2654              "pid {0} mem {1:x}: asked to write {2} bytes, but only found {3} "
2655              "to convert.",
2656              m_current_process->GetID(), write_addr, byte_count, convert_count);
2657     return SendIllFormedResponse(packet, "M content byte length specified did "
2658                                          "not match hex-encoded content "
2659                                          "length");
2660   }
2661 
2662   // Write the process memory.
2663   size_t bytes_written = 0;
2664   Status error = m_current_process->WriteMemory(write_addr, &buf[0], byte_count,
2665                                                 bytes_written);
2666   if (error.Fail()) {
2667     LLDB_LOG(log, "pid {0} mem {1:x}: failed to write. Error: {2}",
2668              m_current_process->GetID(), write_addr, error);
2669     return SendErrorResponse(0x09);
2670   }
2671 
2672   if (bytes_written == 0) {
2673     LLDB_LOG(log, "pid {0} mem {1:x}: wrote 0 of {2} requested bytes",
2674              m_current_process->GetID(), write_addr, byte_count);
2675     return SendErrorResponse(0x09);
2676   }
2677 
2678   return SendOKResponse();
2679 }
2680 
2681 GDBRemoteCommunication::PacketResult
2682 GDBRemoteCommunicationServerLLGS::Handle_qMemoryRegionInfoSupported(
2683     StringExtractorGDBRemote &packet) {
2684   Log *log = GetLog(LLDBLog::Process);
2685 
2686   // Currently only the NativeProcessProtocol knows if it can handle a
2687   // qMemoryRegionInfoSupported request, but we're not guaranteed to be
2688   // attached to a process.  For now we'll assume the client only asks this
2689   // when a process is being debugged.
2690 
2691   // Ensure we have a process running; otherwise, we can't figure this out
2692   // since we won't have a NativeProcessProtocol.
2693   if (!m_current_process ||
2694       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2695     LLDB_LOGF(
2696         log,
2697         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2698         __FUNCTION__);
2699     return SendErrorResponse(0x15);
2700   }
2701 
2702   // Test if we can get any region back when asking for the region around NULL.
2703   MemoryRegionInfo region_info;
2704   const Status error = m_current_process->GetMemoryRegionInfo(0, region_info);
2705   if (error.Fail()) {
2706     // We don't support memory region info collection for this
2707     // NativeProcessProtocol.
2708     return SendUnimplementedResponse("");
2709   }
2710 
2711   return SendOKResponse();
2712 }
2713 
2714 GDBRemoteCommunication::PacketResult
2715 GDBRemoteCommunicationServerLLGS::Handle_qMemoryRegionInfo(
2716     StringExtractorGDBRemote &packet) {
2717   Log *log = GetLog(LLDBLog::Process);
2718 
2719   // Ensure we have a process.
2720   if (!m_current_process ||
2721       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2722     LLDB_LOGF(
2723         log,
2724         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2725         __FUNCTION__);
2726     return SendErrorResponse(0x15);
2727   }
2728 
2729   // Parse out the memory address.
2730   packet.SetFilePos(strlen("qMemoryRegionInfo:"));
2731   if (packet.GetBytesLeft() < 1)
2732     return SendIllFormedResponse(packet, "Too short qMemoryRegionInfo: packet");
2733 
2734   // Read the address.  Punting on validation.
2735   const lldb::addr_t read_addr = packet.GetHexMaxU64(false, 0);
2736 
2737   StreamGDBRemote response;
2738 
2739   // Get the memory region info for the target address.
2740   MemoryRegionInfo region_info;
2741   const Status error =
2742       m_current_process->GetMemoryRegionInfo(read_addr, region_info);
2743   if (error.Fail()) {
2744     // Return the error message.
2745 
2746     response.PutCString("error:");
2747     response.PutStringAsRawHex8(error.AsCString());
2748     response.PutChar(';');
2749   } else {
2750     // Range start and size.
2751     response.Printf("start:%" PRIx64 ";size:%" PRIx64 ";",
2752                     region_info.GetRange().GetRangeBase(),
2753                     region_info.GetRange().GetByteSize());
2754 
2755     // Permissions.
2756     if (region_info.GetReadable() || region_info.GetWritable() ||
2757         region_info.GetExecutable()) {
2758       // Write permissions info.
2759       response.PutCString("permissions:");
2760 
2761       if (region_info.GetReadable())
2762         response.PutChar('r');
2763       if (region_info.GetWritable())
2764         response.PutChar('w');
2765       if (region_info.GetExecutable())
2766         response.PutChar('x');
2767 
2768       response.PutChar(';');
2769     }
2770 
2771     // Flags
2772     MemoryRegionInfo::OptionalBool memory_tagged =
2773         region_info.GetMemoryTagged();
2774     if (memory_tagged != MemoryRegionInfo::eDontKnow) {
2775       response.PutCString("flags:");
2776       if (memory_tagged == MemoryRegionInfo::eYes) {
2777         response.PutCString("mt");
2778       }
2779       response.PutChar(';');
2780     }
2781 
2782     // Name
2783     ConstString name = region_info.GetName();
2784     if (name) {
2785       response.PutCString("name:");
2786       response.PutStringAsRawHex8(name.GetStringRef());
2787       response.PutChar(';');
2788     }
2789   }
2790 
2791   return SendPacketNoLock(response.GetString());
2792 }
2793 
2794 GDBRemoteCommunication::PacketResult
2795 GDBRemoteCommunicationServerLLGS::Handle_Z(StringExtractorGDBRemote &packet) {
2796   // Ensure we have a process.
2797   if (!m_current_process ||
2798       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2799     Log *log = GetLog(LLDBLog::Process);
2800     LLDB_LOG(log, "failed, no process available");
2801     return SendErrorResponse(0x15);
2802   }
2803 
2804   // Parse out software or hardware breakpoint or watchpoint requested.
2805   packet.SetFilePos(strlen("Z"));
2806   if (packet.GetBytesLeft() < 1)
2807     return SendIllFormedResponse(
2808         packet, "Too short Z packet, missing software/hardware specifier");
2809 
2810   bool want_breakpoint = true;
2811   bool want_hardware = false;
2812   uint32_t watch_flags = 0;
2813 
2814   const GDBStoppointType stoppoint_type =
2815       GDBStoppointType(packet.GetS32(eStoppointInvalid));
2816   switch (stoppoint_type) {
2817   case eBreakpointSoftware:
2818     want_hardware = false;
2819     want_breakpoint = true;
2820     break;
2821   case eBreakpointHardware:
2822     want_hardware = true;
2823     want_breakpoint = true;
2824     break;
2825   case eWatchpointWrite:
2826     watch_flags = 1;
2827     want_hardware = true;
2828     want_breakpoint = false;
2829     break;
2830   case eWatchpointRead:
2831     watch_flags = 2;
2832     want_hardware = true;
2833     want_breakpoint = false;
2834     break;
2835   case eWatchpointReadWrite:
2836     watch_flags = 3;
2837     want_hardware = true;
2838     want_breakpoint = false;
2839     break;
2840   case eStoppointInvalid:
2841     return SendIllFormedResponse(
2842         packet, "Z packet had invalid software/hardware specifier");
2843   }
2844 
2845   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2846     return SendIllFormedResponse(
2847         packet, "Malformed Z packet, expecting comma after stoppoint type");
2848 
2849   // Parse out the stoppoint address.
2850   if (packet.GetBytesLeft() < 1)
2851     return SendIllFormedResponse(packet, "Too short Z packet, missing address");
2852   const lldb::addr_t addr = packet.GetHexMaxU64(false, 0);
2853 
2854   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2855     return SendIllFormedResponse(
2856         packet, "Malformed Z packet, expecting comma after address");
2857 
2858   // Parse out the stoppoint size (i.e. size hint for opcode size).
2859   const uint32_t size =
2860       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
2861   if (size == std::numeric_limits<uint32_t>::max())
2862     return SendIllFormedResponse(
2863         packet, "Malformed Z packet, failed to parse size argument");
2864 
2865   if (want_breakpoint) {
2866     // Try to set the breakpoint.
2867     const Status error =
2868         m_current_process->SetBreakpoint(addr, size, want_hardware);
2869     if (error.Success())
2870       return SendOKResponse();
2871     Log *log = GetLog(LLDBLog::Breakpoints);
2872     LLDB_LOG(log, "pid {0} failed to set breakpoint: {1}",
2873              m_current_process->GetID(), error);
2874     return SendErrorResponse(0x09);
2875   } else {
2876     // Try to set the watchpoint.
2877     const Status error = m_current_process->SetWatchpoint(
2878         addr, size, watch_flags, want_hardware);
2879     if (error.Success())
2880       return SendOKResponse();
2881     Log *log = GetLog(LLDBLog::Watchpoints);
2882     LLDB_LOG(log, "pid {0} failed to set watchpoint: {1}",
2883              m_current_process->GetID(), error);
2884     return SendErrorResponse(0x09);
2885   }
2886 }
2887 
2888 GDBRemoteCommunication::PacketResult
2889 GDBRemoteCommunicationServerLLGS::Handle_z(StringExtractorGDBRemote &packet) {
2890   // Ensure we have a process.
2891   if (!m_current_process ||
2892       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2893     Log *log = GetLog(LLDBLog::Process);
2894     LLDB_LOG(log, "failed, no process available");
2895     return SendErrorResponse(0x15);
2896   }
2897 
2898   // Parse out software or hardware breakpoint or watchpoint requested.
2899   packet.SetFilePos(strlen("z"));
2900   if (packet.GetBytesLeft() < 1)
2901     return SendIllFormedResponse(
2902         packet, "Too short z packet, missing software/hardware specifier");
2903 
2904   bool want_breakpoint = true;
2905   bool want_hardware = false;
2906 
2907   const GDBStoppointType stoppoint_type =
2908       GDBStoppointType(packet.GetS32(eStoppointInvalid));
2909   switch (stoppoint_type) {
2910   case eBreakpointHardware:
2911     want_breakpoint = true;
2912     want_hardware = true;
2913     break;
2914   case eBreakpointSoftware:
2915     want_breakpoint = true;
2916     break;
2917   case eWatchpointWrite:
2918     want_breakpoint = false;
2919     break;
2920   case eWatchpointRead:
2921     want_breakpoint = false;
2922     break;
2923   case eWatchpointReadWrite:
2924     want_breakpoint = false;
2925     break;
2926   default:
2927     return SendIllFormedResponse(
2928         packet, "z packet had invalid software/hardware specifier");
2929   }
2930 
2931   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2932     return SendIllFormedResponse(
2933         packet, "Malformed z packet, expecting comma after stoppoint type");
2934 
2935   // Parse out the stoppoint address.
2936   if (packet.GetBytesLeft() < 1)
2937     return SendIllFormedResponse(packet, "Too short z packet, missing address");
2938   const lldb::addr_t addr = packet.GetHexMaxU64(false, 0);
2939 
2940   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2941     return SendIllFormedResponse(
2942         packet, "Malformed z packet, expecting comma after address");
2943 
2944   /*
2945   // Parse out the stoppoint size (i.e. size hint for opcode size).
2946   const uint32_t size = packet.GetHexMaxU32 (false,
2947   std::numeric_limits<uint32_t>::max ());
2948   if (size == std::numeric_limits<uint32_t>::max ())
2949       return SendIllFormedResponse(packet, "Malformed z packet, failed to parse
2950   size argument");
2951   */
2952 
2953   if (want_breakpoint) {
2954     // Try to clear the breakpoint.
2955     const Status error =
2956         m_current_process->RemoveBreakpoint(addr, want_hardware);
2957     if (error.Success())
2958       return SendOKResponse();
2959     Log *log = GetLog(LLDBLog::Breakpoints);
2960     LLDB_LOG(log, "pid {0} failed to remove breakpoint: {1}",
2961              m_current_process->GetID(), error);
2962     return SendErrorResponse(0x09);
2963   } else {
2964     // Try to clear the watchpoint.
2965     const Status error = m_current_process->RemoveWatchpoint(addr);
2966     if (error.Success())
2967       return SendOKResponse();
2968     Log *log = GetLog(LLDBLog::Watchpoints);
2969     LLDB_LOG(log, "pid {0} failed to remove watchpoint: {1}",
2970              m_current_process->GetID(), error);
2971     return SendErrorResponse(0x09);
2972   }
2973 }
2974 
2975 GDBRemoteCommunication::PacketResult
2976 GDBRemoteCommunicationServerLLGS::Handle_s(StringExtractorGDBRemote &packet) {
2977   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
2978 
2979   // Ensure we have a process.
2980   if (!m_continue_process ||
2981       (m_continue_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2982     LLDB_LOGF(
2983         log,
2984         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2985         __FUNCTION__);
2986     return SendErrorResponse(0x32);
2987   }
2988 
2989   // We first try to use a continue thread id.  If any one or any all set, use
2990   // the current thread. Bail out if we don't have a thread id.
2991   lldb::tid_t tid = GetContinueThreadID();
2992   if (tid == 0 || tid == LLDB_INVALID_THREAD_ID)
2993     tid = GetCurrentThreadID();
2994   if (tid == LLDB_INVALID_THREAD_ID)
2995     return SendErrorResponse(0x33);
2996 
2997   // Double check that we have such a thread.
2998   // TODO investigate: on MacOSX we might need to do an UpdateThreads () here.
2999   NativeThreadProtocol *thread = m_continue_process->GetThreadByID(tid);
3000   if (!thread)
3001     return SendErrorResponse(0x33);
3002 
3003   // Create the step action for the given thread.
3004   ResumeAction action = {tid, eStateStepping, LLDB_INVALID_SIGNAL_NUMBER};
3005 
3006   // Setup the actions list.
3007   ResumeActionList actions;
3008   actions.Append(action);
3009 
3010   // All other threads stop while we're single stepping a thread.
3011   actions.SetDefaultThreadActionIfNeeded(eStateStopped, 0);
3012 
3013   PacketResult resume_res = ResumeProcess(*m_continue_process, actions);
3014   if (resume_res != PacketResult::Success)
3015     return resume_res;
3016 
3017   // No response here, unless in non-stop mode.
3018   // Otherwise, the stop or exit will come from the resulting action.
3019   return SendContinueSuccessResponse();
3020 }
3021 
3022 llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>>
3023 GDBRemoteCommunicationServerLLGS::BuildTargetXml() {
3024   // Ensure we have a thread.
3025   NativeThreadProtocol *thread = m_current_process->GetThreadAtIndex(0);
3026   if (!thread)
3027     return llvm::createStringError(llvm::inconvertibleErrorCode(),
3028                                    "No thread available");
3029 
3030   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
3031   // Get the register context for the first thread.
3032   NativeRegisterContext &reg_context = thread->GetRegisterContext();
3033 
3034   StreamString response;
3035 
3036   response.Printf("<?xml version=\"1.0\"?>");
3037   response.Printf("<target version=\"1.0\">");
3038 
3039   response.Printf("<architecture>%s</architecture>",
3040                   m_current_process->GetArchitecture()
3041                       .GetTriple()
3042                       .getArchName()
3043                       .str()
3044                       .c_str());
3045 
3046   response.Printf("<feature>");
3047 
3048   const int registers_count = reg_context.GetUserRegisterCount();
3049   for (int reg_index = 0; reg_index < registers_count; reg_index++) {
3050     const RegisterInfo *reg_info =
3051         reg_context.GetRegisterInfoAtIndex(reg_index);
3052 
3053     if (!reg_info) {
3054       LLDB_LOGF(log,
3055                 "%s failed to get register info for register index %" PRIu32,
3056                 "target.xml", reg_index);
3057       continue;
3058     }
3059 
3060     response.Printf("<reg name=\"%s\" bitsize=\"%" PRIu32 "\" regnum=\"%d\" ",
3061                     reg_info->name, reg_info->byte_size * 8, reg_index);
3062 
3063     if (!reg_context.RegisterOffsetIsDynamic())
3064       response.Printf("offset=\"%" PRIu32 "\" ", reg_info->byte_offset);
3065 
3066     if (reg_info->alt_name && reg_info->alt_name[0])
3067       response.Printf("altname=\"%s\" ", reg_info->alt_name);
3068 
3069     llvm::StringRef encoding = GetEncodingNameOrEmpty(*reg_info);
3070     if (!encoding.empty())
3071       response << "encoding=\"" << encoding << "\" ";
3072 
3073     llvm::StringRef format = GetFormatNameOrEmpty(*reg_info);
3074     if (!format.empty())
3075       response << "format=\"" << format << "\" ";
3076 
3077     const char *const register_set_name =
3078         reg_context.GetRegisterSetNameForRegisterAtIndex(reg_index);
3079     if (register_set_name)
3080       response << "group=\"" << register_set_name << "\" ";
3081 
3082     if (reg_info->kinds[RegisterKind::eRegisterKindEHFrame] !=
3083         LLDB_INVALID_REGNUM)
3084       response.Printf("ehframe_regnum=\"%" PRIu32 "\" ",
3085                       reg_info->kinds[RegisterKind::eRegisterKindEHFrame]);
3086 
3087     if (reg_info->kinds[RegisterKind::eRegisterKindDWARF] !=
3088         LLDB_INVALID_REGNUM)
3089       response.Printf("dwarf_regnum=\"%" PRIu32 "\" ",
3090                       reg_info->kinds[RegisterKind::eRegisterKindDWARF]);
3091 
3092     llvm::StringRef kind_generic = GetKindGenericOrEmpty(*reg_info);
3093     if (!kind_generic.empty())
3094       response << "generic=\"" << kind_generic << "\" ";
3095 
3096     if (reg_info->value_regs &&
3097         reg_info->value_regs[0] != LLDB_INVALID_REGNUM) {
3098       response.PutCString("value_regnums=\"");
3099       CollectRegNums(reg_info->value_regs, response, false);
3100       response.Printf("\" ");
3101     }
3102 
3103     if (reg_info->invalidate_regs && reg_info->invalidate_regs[0]) {
3104       response.PutCString("invalidate_regnums=\"");
3105       CollectRegNums(reg_info->invalidate_regs, response, false);
3106       response.Printf("\" ");
3107     }
3108 
3109     response.Printf("/>");
3110   }
3111 
3112   response.Printf("</feature>");
3113   response.Printf("</target>");
3114   return MemoryBuffer::getMemBufferCopy(response.GetString(), "target.xml");
3115 }
3116 
3117 llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>>
3118 GDBRemoteCommunicationServerLLGS::ReadXferObject(llvm::StringRef object,
3119                                                  llvm::StringRef annex) {
3120   // Make sure we have a valid process.
3121   if (!m_current_process ||
3122       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
3123     return llvm::createStringError(llvm::inconvertibleErrorCode(),
3124                                    "No process available");
3125   }
3126 
3127   if (object == "auxv") {
3128     // Grab the auxv data.
3129     auto buffer_or_error = m_current_process->GetAuxvData();
3130     if (!buffer_or_error)
3131       return llvm::errorCodeToError(buffer_or_error.getError());
3132     return std::move(*buffer_or_error);
3133   }
3134 
3135   if (object == "siginfo") {
3136     NativeThreadProtocol *thread = m_current_process->GetCurrentThread();
3137     if (!thread)
3138       return llvm::createStringError(llvm::inconvertibleErrorCode(),
3139                                      "no current thread");
3140 
3141     auto buffer_or_error = thread->GetSiginfo();
3142     if (!buffer_or_error)
3143       return buffer_or_error.takeError();
3144     return std::move(*buffer_or_error);
3145   }
3146 
3147   if (object == "libraries-svr4") {
3148     auto library_list = m_current_process->GetLoadedSVR4Libraries();
3149     if (!library_list)
3150       return library_list.takeError();
3151 
3152     StreamString response;
3153     response.Printf("<library-list-svr4 version=\"1.0\">");
3154     for (auto const &library : *library_list) {
3155       response.Printf("<library name=\"%s\" ",
3156                       XMLEncodeAttributeValue(library.name.c_str()).c_str());
3157       response.Printf("lm=\"0x%" PRIx64 "\" ", library.link_map);
3158       response.Printf("l_addr=\"0x%" PRIx64 "\" ", library.base_addr);
3159       response.Printf("l_ld=\"0x%" PRIx64 "\" />", library.ld_addr);
3160     }
3161     response.Printf("</library-list-svr4>");
3162     return MemoryBuffer::getMemBufferCopy(response.GetString(), __FUNCTION__);
3163   }
3164 
3165   if (object == "features" && annex == "target.xml")
3166     return BuildTargetXml();
3167 
3168   return llvm::make_error<UnimplementedError>();
3169 }
3170 
3171 GDBRemoteCommunication::PacketResult
3172 GDBRemoteCommunicationServerLLGS::Handle_qXfer(
3173     StringExtractorGDBRemote &packet) {
3174   SmallVector<StringRef, 5> fields;
3175   // The packet format is "qXfer:<object>:<action>:<annex>:offset,length"
3176   StringRef(packet.GetStringRef()).split(fields, ':', 4);
3177   if (fields.size() != 5)
3178     return SendIllFormedResponse(packet, "malformed qXfer packet");
3179   StringRef &xfer_object = fields[1];
3180   StringRef &xfer_action = fields[2];
3181   StringRef &xfer_annex = fields[3];
3182   StringExtractor offset_data(fields[4]);
3183   if (xfer_action != "read")
3184     return SendUnimplementedResponse("qXfer action not supported");
3185   // Parse offset.
3186   const uint64_t xfer_offset =
3187       offset_data.GetHexMaxU64(false, std::numeric_limits<uint64_t>::max());
3188   if (xfer_offset == std::numeric_limits<uint64_t>::max())
3189     return SendIllFormedResponse(packet, "qXfer packet missing offset");
3190   // Parse out comma.
3191   if (offset_data.GetChar() != ',')
3192     return SendIllFormedResponse(packet,
3193                                  "qXfer packet missing comma after offset");
3194   // Parse out the length.
3195   const uint64_t xfer_length =
3196       offset_data.GetHexMaxU64(false, std::numeric_limits<uint64_t>::max());
3197   if (xfer_length == std::numeric_limits<uint64_t>::max())
3198     return SendIllFormedResponse(packet, "qXfer packet missing length");
3199 
3200   // Get a previously constructed buffer if it exists or create it now.
3201   std::string buffer_key = (xfer_object + xfer_action + xfer_annex).str();
3202   auto buffer_it = m_xfer_buffer_map.find(buffer_key);
3203   if (buffer_it == m_xfer_buffer_map.end()) {
3204     auto buffer_up = ReadXferObject(xfer_object, xfer_annex);
3205     if (!buffer_up)
3206       return SendErrorResponse(buffer_up.takeError());
3207     buffer_it = m_xfer_buffer_map
3208                     .insert(std::make_pair(buffer_key, std::move(*buffer_up)))
3209                     .first;
3210   }
3211 
3212   // Send back the response
3213   StreamGDBRemote response;
3214   bool done_with_buffer = false;
3215   llvm::StringRef buffer = buffer_it->second->getBuffer();
3216   if (xfer_offset >= buffer.size()) {
3217     // We have nothing left to send.  Mark the buffer as complete.
3218     response.PutChar('l');
3219     done_with_buffer = true;
3220   } else {
3221     // Figure out how many bytes are available starting at the given offset.
3222     buffer = buffer.drop_front(xfer_offset);
3223     // Mark the response type according to whether we're reading the remainder
3224     // of the data.
3225     if (xfer_length >= buffer.size()) {
3226       // There will be nothing left to read after this
3227       response.PutChar('l');
3228       done_with_buffer = true;
3229     } else {
3230       // There will still be bytes to read after this request.
3231       response.PutChar('m');
3232       buffer = buffer.take_front(xfer_length);
3233     }
3234     // Now write the data in encoded binary form.
3235     response.PutEscapedBytes(buffer.data(), buffer.size());
3236   }
3237 
3238   if (done_with_buffer)
3239     m_xfer_buffer_map.erase(buffer_it);
3240 
3241   return SendPacketNoLock(response.GetString());
3242 }
3243 
3244 GDBRemoteCommunication::PacketResult
3245 GDBRemoteCommunicationServerLLGS::Handle_QSaveRegisterState(
3246     StringExtractorGDBRemote &packet) {
3247   Log *log = GetLog(LLDBLog::Thread);
3248 
3249   // Move past packet name.
3250   packet.SetFilePos(strlen("QSaveRegisterState"));
3251 
3252   // Get the thread to use.
3253   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
3254   if (!thread) {
3255     if (m_thread_suffix_supported)
3256       return SendIllFormedResponse(
3257           packet, "No thread specified in QSaveRegisterState packet");
3258     else
3259       return SendIllFormedResponse(packet,
3260                                    "No thread was is set with the Hg packet");
3261   }
3262 
3263   // Grab the register context for the thread.
3264   NativeRegisterContext& reg_context = thread->GetRegisterContext();
3265 
3266   // Save registers to a buffer.
3267   WritableDataBufferSP register_data_sp;
3268   Status error = reg_context.ReadAllRegisterValues(register_data_sp);
3269   if (error.Fail()) {
3270     LLDB_LOG(log, "pid {0} failed to save all register values: {1}",
3271              m_current_process->GetID(), error);
3272     return SendErrorResponse(0x75);
3273   }
3274 
3275   // Allocate a new save id.
3276   const uint32_t save_id = GetNextSavedRegistersID();
3277   assert((m_saved_registers_map.find(save_id) == m_saved_registers_map.end()) &&
3278          "GetNextRegisterSaveID() returned an existing register save id");
3279 
3280   // Save the register data buffer under the save id.
3281   {
3282     std::lock_guard<std::mutex> guard(m_saved_registers_mutex);
3283     m_saved_registers_map[save_id] = register_data_sp;
3284   }
3285 
3286   // Write the response.
3287   StreamGDBRemote response;
3288   response.Printf("%" PRIu32, save_id);
3289   return SendPacketNoLock(response.GetString());
3290 }
3291 
3292 GDBRemoteCommunication::PacketResult
3293 GDBRemoteCommunicationServerLLGS::Handle_QRestoreRegisterState(
3294     StringExtractorGDBRemote &packet) {
3295   Log *log = GetLog(LLDBLog::Thread);
3296 
3297   // Parse out save id.
3298   packet.SetFilePos(strlen("QRestoreRegisterState:"));
3299   if (packet.GetBytesLeft() < 1)
3300     return SendIllFormedResponse(
3301         packet, "QRestoreRegisterState packet missing register save id");
3302 
3303   const uint32_t save_id = packet.GetU32(0);
3304   if (save_id == 0) {
3305     LLDB_LOG(log, "QRestoreRegisterState packet has malformed save id, "
3306                   "expecting decimal uint32_t");
3307     return SendErrorResponse(0x76);
3308   }
3309 
3310   // Get the thread to use.
3311   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
3312   if (!thread) {
3313     if (m_thread_suffix_supported)
3314       return SendIllFormedResponse(
3315           packet, "No thread specified in QRestoreRegisterState packet");
3316     else
3317       return SendIllFormedResponse(packet,
3318                                    "No thread was is set with the Hg packet");
3319   }
3320 
3321   // Grab the register context for the thread.
3322   NativeRegisterContext &reg_context = thread->GetRegisterContext();
3323 
3324   // Retrieve register state buffer, then remove from the list.
3325   DataBufferSP register_data_sp;
3326   {
3327     std::lock_guard<std::mutex> guard(m_saved_registers_mutex);
3328 
3329     // Find the register set buffer for the given save id.
3330     auto it = m_saved_registers_map.find(save_id);
3331     if (it == m_saved_registers_map.end()) {
3332       LLDB_LOG(log,
3333                "pid {0} does not have a register set save buffer for id {1}",
3334                m_current_process->GetID(), save_id);
3335       return SendErrorResponse(0x77);
3336     }
3337     register_data_sp = it->second;
3338 
3339     // Remove it from the map.
3340     m_saved_registers_map.erase(it);
3341   }
3342 
3343   Status error = reg_context.WriteAllRegisterValues(register_data_sp);
3344   if (error.Fail()) {
3345     LLDB_LOG(log, "pid {0} failed to restore all register values: {1}",
3346              m_current_process->GetID(), error);
3347     return SendErrorResponse(0x77);
3348   }
3349 
3350   return SendOKResponse();
3351 }
3352 
3353 GDBRemoteCommunication::PacketResult
3354 GDBRemoteCommunicationServerLLGS::Handle_vAttach(
3355     StringExtractorGDBRemote &packet) {
3356   Log *log = GetLog(LLDBLog::Process);
3357 
3358   // Consume the ';' after vAttach.
3359   packet.SetFilePos(strlen("vAttach"));
3360   if (!packet.GetBytesLeft() || packet.GetChar() != ';')
3361     return SendIllFormedResponse(packet, "vAttach missing expected ';'");
3362 
3363   // Grab the PID to which we will attach (assume hex encoding).
3364   lldb::pid_t pid = packet.GetU32(LLDB_INVALID_PROCESS_ID, 16);
3365   if (pid == LLDB_INVALID_PROCESS_ID)
3366     return SendIllFormedResponse(packet,
3367                                  "vAttach failed to parse the process id");
3368 
3369   // Attempt to attach.
3370   LLDB_LOGF(log,
3371             "GDBRemoteCommunicationServerLLGS::%s attempting to attach to "
3372             "pid %" PRIu64,
3373             __FUNCTION__, pid);
3374 
3375   Status error = AttachToProcess(pid);
3376 
3377   if (error.Fail()) {
3378     LLDB_LOGF(log,
3379               "GDBRemoteCommunicationServerLLGS::%s failed to attach to "
3380               "pid %" PRIu64 ": %s\n",
3381               __FUNCTION__, pid, error.AsCString());
3382     return SendErrorResponse(error);
3383   }
3384 
3385   // Notify we attached by sending a stop packet.
3386   assert(m_current_process);
3387   return SendStopReasonForState(*m_current_process,
3388                                 m_current_process->GetState(),
3389                                 /*force_synchronous=*/false);
3390 }
3391 
3392 GDBRemoteCommunication::PacketResult
3393 GDBRemoteCommunicationServerLLGS::Handle_vAttachWait(
3394     StringExtractorGDBRemote &packet) {
3395   Log *log = GetLog(LLDBLog::Process);
3396 
3397   // Consume the ';' after the identifier.
3398   packet.SetFilePos(strlen("vAttachWait"));
3399 
3400   if (!packet.GetBytesLeft() || packet.GetChar() != ';')
3401     return SendIllFormedResponse(packet, "vAttachWait missing expected ';'");
3402 
3403   // Allocate the buffer for the process name from vAttachWait.
3404   std::string process_name;
3405   if (!packet.GetHexByteString(process_name))
3406     return SendIllFormedResponse(packet,
3407                                  "vAttachWait failed to parse process name");
3408 
3409   LLDB_LOG(log, "attempting to attach to process named '{0}'", process_name);
3410 
3411   Status error = AttachWaitProcess(process_name, false);
3412   if (error.Fail()) {
3413     LLDB_LOG(log, "failed to attach to process named '{0}': {1}", process_name,
3414              error);
3415     return SendErrorResponse(error);
3416   }
3417 
3418   // Notify we attached by sending a stop packet.
3419   assert(m_current_process);
3420   return SendStopReasonForState(*m_current_process,
3421                                 m_current_process->GetState(),
3422                                 /*force_synchronous=*/false);
3423 }
3424 
3425 GDBRemoteCommunication::PacketResult
3426 GDBRemoteCommunicationServerLLGS::Handle_qVAttachOrWaitSupported(
3427     StringExtractorGDBRemote &packet) {
3428   return SendOKResponse();
3429 }
3430 
3431 GDBRemoteCommunication::PacketResult
3432 GDBRemoteCommunicationServerLLGS::Handle_vAttachOrWait(
3433     StringExtractorGDBRemote &packet) {
3434   Log *log = GetLog(LLDBLog::Process);
3435 
3436   // Consume the ';' after the identifier.
3437   packet.SetFilePos(strlen("vAttachOrWait"));
3438 
3439   if (!packet.GetBytesLeft() || packet.GetChar() != ';')
3440     return SendIllFormedResponse(packet, "vAttachOrWait missing expected ';'");
3441 
3442   // Allocate the buffer for the process name from vAttachWait.
3443   std::string process_name;
3444   if (!packet.GetHexByteString(process_name))
3445     return SendIllFormedResponse(packet,
3446                                  "vAttachOrWait failed to parse process name");
3447 
3448   LLDB_LOG(log, "attempting to attach to process named '{0}'", process_name);
3449 
3450   Status error = AttachWaitProcess(process_name, true);
3451   if (error.Fail()) {
3452     LLDB_LOG(log, "failed to attach to process named '{0}': {1}", process_name,
3453              error);
3454     return SendErrorResponse(error);
3455   }
3456 
3457   // Notify we attached by sending a stop packet.
3458   assert(m_current_process);
3459   return SendStopReasonForState(*m_current_process,
3460                                 m_current_process->GetState(),
3461                                 /*force_synchronous=*/false);
3462 }
3463 
3464 GDBRemoteCommunication::PacketResult
3465 GDBRemoteCommunicationServerLLGS::Handle_vRun(
3466     StringExtractorGDBRemote &packet) {
3467   Log *log = GetLog(LLDBLog::Process);
3468 
3469   llvm::StringRef s = packet.GetStringRef();
3470   if (!s.consume_front("vRun;"))
3471     return SendErrorResponse(8);
3472 
3473   llvm::SmallVector<llvm::StringRef, 16> argv;
3474   s.split(argv, ';');
3475 
3476   for (llvm::StringRef hex_arg : argv) {
3477     StringExtractor arg_ext{hex_arg};
3478     std::string arg;
3479     arg_ext.GetHexByteString(arg);
3480     m_process_launch_info.GetArguments().AppendArgument(arg);
3481     LLDB_LOGF(log, "LLGSPacketHandler::%s added arg: \"%s\"", __FUNCTION__,
3482               arg.c_str());
3483   }
3484 
3485   if (!argv.empty()) {
3486     m_process_launch_info.GetExecutableFile().SetFile(
3487         m_process_launch_info.GetArguments()[0].ref(), FileSpec::Style::native);
3488     m_process_launch_error = LaunchProcess();
3489     if (m_process_launch_error.Success()) {
3490       assert(m_current_process);
3491       return SendStopReasonForState(*m_current_process,
3492                                     m_current_process->GetState(),
3493                                     /*force_synchronous=*/true);
3494     }
3495     LLDB_LOG(log, "failed to launch exe: {0}", m_process_launch_error);
3496   }
3497   return SendErrorResponse(8);
3498 }
3499 
3500 GDBRemoteCommunication::PacketResult
3501 GDBRemoteCommunicationServerLLGS::Handle_D(StringExtractorGDBRemote &packet) {
3502   Log *log = GetLog(LLDBLog::Process);
3503   StopSTDIOForwarding();
3504 
3505   lldb::pid_t pid = LLDB_INVALID_PROCESS_ID;
3506 
3507   // Consume the ';' after D.
3508   packet.SetFilePos(1);
3509   if (packet.GetBytesLeft()) {
3510     if (packet.GetChar() != ';')
3511       return SendIllFormedResponse(packet, "D missing expected ';'");
3512 
3513     // Grab the PID from which we will detach (assume hex encoding).
3514     pid = packet.GetU32(LLDB_INVALID_PROCESS_ID, 16);
3515     if (pid == LLDB_INVALID_PROCESS_ID)
3516       return SendIllFormedResponse(packet, "D failed to parse the process id");
3517   }
3518 
3519   // Detach forked children if their PID was specified *or* no PID was requested
3520   // (i.e. detach-all packet).
3521   llvm::Error detach_error = llvm::Error::success();
3522   bool detached = false;
3523   for (auto it = m_debugged_processes.begin();
3524        it != m_debugged_processes.end();) {
3525     if (pid == LLDB_INVALID_PROCESS_ID || pid == it->first) {
3526       LLDB_LOGF(log,
3527                 "GDBRemoteCommunicationServerLLGS::%s detaching %" PRId64,
3528                 __FUNCTION__, it->first);
3529       if (llvm::Error e = it->second.process_up->Detach().ToError())
3530         detach_error = llvm::joinErrors(std::move(detach_error), std::move(e));
3531       else {
3532         if (it->second.process_up.get() == m_current_process)
3533           m_current_process = nullptr;
3534         if (it->second.process_up.get() == m_continue_process)
3535           m_continue_process = nullptr;
3536         it = m_debugged_processes.erase(it);
3537         detached = true;
3538         continue;
3539       }
3540     }
3541     ++it;
3542   }
3543 
3544   if (detach_error)
3545     return SendErrorResponse(std::move(detach_error));
3546   if (!detached)
3547     return SendErrorResponse(Status("PID %" PRIu64 " not traced", pid));
3548   return SendOKResponse();
3549 }
3550 
3551 GDBRemoteCommunication::PacketResult
3552 GDBRemoteCommunicationServerLLGS::Handle_qThreadStopInfo(
3553     StringExtractorGDBRemote &packet) {
3554   Log *log = GetLog(LLDBLog::Thread);
3555 
3556   if (!m_current_process ||
3557       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
3558     return SendErrorResponse(50);
3559 
3560   packet.SetFilePos(strlen("qThreadStopInfo"));
3561   const lldb::tid_t tid = packet.GetHexMaxU64(false, LLDB_INVALID_THREAD_ID);
3562   if (tid == LLDB_INVALID_THREAD_ID) {
3563     LLDB_LOGF(log,
3564               "GDBRemoteCommunicationServerLLGS::%s failed, could not "
3565               "parse thread id from request \"%s\"",
3566               __FUNCTION__, packet.GetStringRef().data());
3567     return SendErrorResponse(0x15);
3568   }
3569   return SendStopReplyPacketForThread(*m_current_process, tid,
3570                                       /*force_synchronous=*/true);
3571 }
3572 
3573 GDBRemoteCommunication::PacketResult
3574 GDBRemoteCommunicationServerLLGS::Handle_jThreadsInfo(
3575     StringExtractorGDBRemote &) {
3576   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
3577 
3578   // Ensure we have a debugged process.
3579   if (!m_current_process ||
3580       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
3581     return SendErrorResponse(50);
3582   LLDB_LOG(log, "preparing packet for pid {0}", m_current_process->GetID());
3583 
3584   StreamString response;
3585   const bool threads_with_valid_stop_info_only = false;
3586   llvm::Expected<json::Value> threads_info =
3587       GetJSONThreadsInfo(*m_current_process, threads_with_valid_stop_info_only);
3588   if (!threads_info) {
3589     LLDB_LOG_ERROR(log, threads_info.takeError(),
3590                    "failed to prepare a packet for pid {1}: {0}",
3591                    m_current_process->GetID());
3592     return SendErrorResponse(52);
3593   }
3594 
3595   response.AsRawOstream() << *threads_info;
3596   StreamGDBRemote escaped_response;
3597   escaped_response.PutEscapedBytes(response.GetData(), response.GetSize());
3598   return SendPacketNoLock(escaped_response.GetString());
3599 }
3600 
3601 GDBRemoteCommunication::PacketResult
3602 GDBRemoteCommunicationServerLLGS::Handle_qWatchpointSupportInfo(
3603     StringExtractorGDBRemote &packet) {
3604   // Fail if we don't have a current process.
3605   if (!m_current_process ||
3606       m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)
3607     return SendErrorResponse(68);
3608 
3609   packet.SetFilePos(strlen("qWatchpointSupportInfo"));
3610   if (packet.GetBytesLeft() == 0)
3611     return SendOKResponse();
3612   if (packet.GetChar() != ':')
3613     return SendErrorResponse(67);
3614 
3615   auto hw_debug_cap = m_current_process->GetHardwareDebugSupportInfo();
3616 
3617   StreamGDBRemote response;
3618   if (hw_debug_cap == llvm::None)
3619     response.Printf("num:0;");
3620   else
3621     response.Printf("num:%d;", hw_debug_cap->second);
3622 
3623   return SendPacketNoLock(response.GetString());
3624 }
3625 
3626 GDBRemoteCommunication::PacketResult
3627 GDBRemoteCommunicationServerLLGS::Handle_qFileLoadAddress(
3628     StringExtractorGDBRemote &packet) {
3629   // Fail if we don't have a current process.
3630   if (!m_current_process ||
3631       m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)
3632     return SendErrorResponse(67);
3633 
3634   packet.SetFilePos(strlen("qFileLoadAddress:"));
3635   if (packet.GetBytesLeft() == 0)
3636     return SendErrorResponse(68);
3637 
3638   std::string file_name;
3639   packet.GetHexByteString(file_name);
3640 
3641   lldb::addr_t file_load_address = LLDB_INVALID_ADDRESS;
3642   Status error =
3643       m_current_process->GetFileLoadAddress(file_name, file_load_address);
3644   if (error.Fail())
3645     return SendErrorResponse(69);
3646 
3647   if (file_load_address == LLDB_INVALID_ADDRESS)
3648     return SendErrorResponse(1); // File not loaded
3649 
3650   StreamGDBRemote response;
3651   response.PutHex64(file_load_address);
3652   return SendPacketNoLock(response.GetString());
3653 }
3654 
3655 GDBRemoteCommunication::PacketResult
3656 GDBRemoteCommunicationServerLLGS::Handle_QPassSignals(
3657     StringExtractorGDBRemote &packet) {
3658   std::vector<int> signals;
3659   packet.SetFilePos(strlen("QPassSignals:"));
3660 
3661   // Read sequence of hex signal numbers divided by a semicolon and optionally
3662   // spaces.
3663   while (packet.GetBytesLeft() > 0) {
3664     int signal = packet.GetS32(-1, 16);
3665     if (signal < 0)
3666       return SendIllFormedResponse(packet, "Failed to parse signal number.");
3667     signals.push_back(signal);
3668 
3669     packet.SkipSpaces();
3670     char separator = packet.GetChar();
3671     if (separator == '\0')
3672       break; // End of string
3673     if (separator != ';')
3674       return SendIllFormedResponse(packet, "Invalid separator,"
3675                                             " expected semicolon.");
3676   }
3677 
3678   // Fail if we don't have a current process.
3679   if (!m_current_process)
3680     return SendErrorResponse(68);
3681 
3682   Status error = m_current_process->IgnoreSignals(signals);
3683   if (error.Fail())
3684     return SendErrorResponse(69);
3685 
3686   return SendOKResponse();
3687 }
3688 
3689 GDBRemoteCommunication::PacketResult
3690 GDBRemoteCommunicationServerLLGS::Handle_qMemTags(
3691     StringExtractorGDBRemote &packet) {
3692   Log *log = GetLog(LLDBLog::Process);
3693 
3694   // Ensure we have a process.
3695   if (!m_current_process ||
3696       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
3697     LLDB_LOGF(
3698         log,
3699         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
3700         __FUNCTION__);
3701     return SendErrorResponse(1);
3702   }
3703 
3704   // We are expecting
3705   // qMemTags:<hex address>,<hex length>:<hex type>
3706 
3707   // Address
3708   packet.SetFilePos(strlen("qMemTags:"));
3709   const char *current_char = packet.Peek();
3710   if (!current_char || *current_char == ',')
3711     return SendIllFormedResponse(packet, "Missing address in qMemTags packet");
3712   const lldb::addr_t addr = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3713 
3714   // Length
3715   char previous_char = packet.GetChar();
3716   current_char = packet.Peek();
3717   // If we don't have a separator or the length field is empty
3718   if (previous_char != ',' || (current_char && *current_char == ':'))
3719     return SendIllFormedResponse(packet,
3720                                  "Invalid addr,length pair in qMemTags packet");
3721 
3722   if (packet.GetBytesLeft() < 1)
3723     return SendIllFormedResponse(
3724         packet, "Too short qMemtags: packet (looking for length)");
3725   const size_t length = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3726 
3727   // Type
3728   const char *invalid_type_err = "Invalid type field in qMemTags: packet";
3729   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ':')
3730     return SendIllFormedResponse(packet, invalid_type_err);
3731 
3732   // Type is a signed integer but packed into the packet as its raw bytes.
3733   // However, our GetU64 uses strtoull which allows +/-. We do not want this.
3734   const char *first_type_char = packet.Peek();
3735   if (first_type_char && (*first_type_char == '+' || *first_type_char == '-'))
3736     return SendIllFormedResponse(packet, invalid_type_err);
3737 
3738   // Extract type as unsigned then cast to signed.
3739   // Using a uint64_t here so that we have some value outside of the 32 bit
3740   // range to use as the invalid return value.
3741   uint64_t raw_type =
3742       packet.GetU64(std::numeric_limits<uint64_t>::max(), /*base=*/16);
3743 
3744   if ( // Make sure the cast below would be valid
3745       raw_type > std::numeric_limits<uint32_t>::max() ||
3746       // To catch inputs like "123aardvark" that will parse but clearly aren't
3747       // valid in this case.
3748       packet.GetBytesLeft()) {
3749     return SendIllFormedResponse(packet, invalid_type_err);
3750   }
3751 
3752   // First narrow to 32 bits otherwise the copy into type would take
3753   // the wrong 4 bytes on big endian.
3754   uint32_t raw_type_32 = raw_type;
3755   int32_t type = reinterpret_cast<int32_t &>(raw_type_32);
3756 
3757   StreamGDBRemote response;
3758   std::vector<uint8_t> tags;
3759   Status error = m_current_process->ReadMemoryTags(type, addr, length, tags);
3760   if (error.Fail())
3761     return SendErrorResponse(1);
3762 
3763   // This m is here in case we want to support multi part replies in the future.
3764   // In the same manner as qfThreadInfo/qsThreadInfo.
3765   response.PutChar('m');
3766   response.PutBytesAsRawHex8(tags.data(), tags.size());
3767   return SendPacketNoLock(response.GetString());
3768 }
3769 
3770 GDBRemoteCommunication::PacketResult
3771 GDBRemoteCommunicationServerLLGS::Handle_QMemTags(
3772     StringExtractorGDBRemote &packet) {
3773   Log *log = GetLog(LLDBLog::Process);
3774 
3775   // Ensure we have a process.
3776   if (!m_current_process ||
3777       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
3778     LLDB_LOGF(
3779         log,
3780         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
3781         __FUNCTION__);
3782     return SendErrorResponse(1);
3783   }
3784 
3785   // We are expecting
3786   // QMemTags:<hex address>,<hex length>:<hex type>:<tags as hex bytes>
3787 
3788   // Address
3789   packet.SetFilePos(strlen("QMemTags:"));
3790   const char *current_char = packet.Peek();
3791   if (!current_char || *current_char == ',')
3792     return SendIllFormedResponse(packet, "Missing address in QMemTags packet");
3793   const lldb::addr_t addr = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3794 
3795   // Length
3796   char previous_char = packet.GetChar();
3797   current_char = packet.Peek();
3798   // If we don't have a separator or the length field is empty
3799   if (previous_char != ',' || (current_char && *current_char == ':'))
3800     return SendIllFormedResponse(packet,
3801                                  "Invalid addr,length pair in QMemTags packet");
3802 
3803   if (packet.GetBytesLeft() < 1)
3804     return SendIllFormedResponse(
3805         packet, "Too short QMemtags: packet (looking for length)");
3806   const size_t length = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3807 
3808   // Type
3809   const char *invalid_type_err = "Invalid type field in QMemTags: packet";
3810   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ':')
3811     return SendIllFormedResponse(packet, invalid_type_err);
3812 
3813   // Our GetU64 uses strtoull which allows leading +/-, we don't want that.
3814   const char *first_type_char = packet.Peek();
3815   if (first_type_char && (*first_type_char == '+' || *first_type_char == '-'))
3816     return SendIllFormedResponse(packet, invalid_type_err);
3817 
3818   // The type is a signed integer but is in the packet as its raw bytes.
3819   // So parse first as unsigned then cast to signed later.
3820   // We extract to 64 bit, even though we only expect 32, so that we've
3821   // got some invalid value we can check for.
3822   uint64_t raw_type =
3823       packet.GetU64(std::numeric_limits<uint64_t>::max(), /*base=*/16);
3824   if (raw_type > std::numeric_limits<uint32_t>::max())
3825     return SendIllFormedResponse(packet, invalid_type_err);
3826 
3827   // First narrow to 32 bits. Otherwise the copy below would get the wrong
3828   // 4 bytes on big endian.
3829   uint32_t raw_type_32 = raw_type;
3830   int32_t type = reinterpret_cast<int32_t &>(raw_type_32);
3831 
3832   // Tag data
3833   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ':')
3834     return SendIllFormedResponse(packet,
3835                                  "Missing tag data in QMemTags: packet");
3836 
3837   // Must be 2 chars per byte
3838   const char *invalid_data_err = "Invalid tag data in QMemTags: packet";
3839   if (packet.GetBytesLeft() % 2)
3840     return SendIllFormedResponse(packet, invalid_data_err);
3841 
3842   // This is bytes here and is unpacked into target specific tags later
3843   // We cannot assume that number of bytes == length here because the server
3844   // can repeat tags to fill a given range.
3845   std::vector<uint8_t> tag_data;
3846   // Zero length writes will not have any tag data
3847   // (but we pass them on because it will still check that tagging is enabled)
3848   if (packet.GetBytesLeft()) {
3849     size_t byte_count = packet.GetBytesLeft() / 2;
3850     tag_data.resize(byte_count);
3851     size_t converted_bytes = packet.GetHexBytes(tag_data, 0);
3852     if (converted_bytes != byte_count) {
3853       return SendIllFormedResponse(packet, invalid_data_err);
3854     }
3855   }
3856 
3857   Status status =
3858       m_current_process->WriteMemoryTags(type, addr, length, tag_data);
3859   return status.Success() ? SendOKResponse() : SendErrorResponse(1);
3860 }
3861 
3862 GDBRemoteCommunication::PacketResult
3863 GDBRemoteCommunicationServerLLGS::Handle_qSaveCore(
3864     StringExtractorGDBRemote &packet) {
3865   // Fail if we don't have a current process.
3866   if (!m_current_process ||
3867       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
3868     return SendErrorResponse(Status("Process not running."));
3869 
3870   std::string path_hint;
3871 
3872   StringRef packet_str{packet.GetStringRef()};
3873   assert(packet_str.startswith("qSaveCore"));
3874   if (packet_str.consume_front("qSaveCore;")) {
3875     for (auto x : llvm::split(packet_str, ';')) {
3876       if (x.consume_front("path-hint:"))
3877         StringExtractor(x).GetHexByteString(path_hint);
3878       else
3879         return SendErrorResponse(Status("Unsupported qSaveCore option"));
3880     }
3881   }
3882 
3883   llvm::Expected<std::string> ret = m_current_process->SaveCore(path_hint);
3884   if (!ret)
3885     return SendErrorResponse(ret.takeError());
3886 
3887   StreamString response;
3888   response.PutCString("core-path:");
3889   response.PutStringAsRawHex8(ret.get());
3890   return SendPacketNoLock(response.GetString());
3891 }
3892 
3893 GDBRemoteCommunication::PacketResult
3894 GDBRemoteCommunicationServerLLGS::Handle_QNonStop(
3895     StringExtractorGDBRemote &packet) {
3896   StringRef packet_str{packet.GetStringRef()};
3897   assert(packet_str.startswith("QNonStop:"));
3898   packet_str.consume_front("QNonStop:");
3899   if (packet_str == "0") {
3900     m_non_stop = false;
3901     // TODO: stop all threads
3902   } else if (packet_str == "1") {
3903     m_non_stop = true;
3904   } else
3905     return SendErrorResponse(Status("Invalid QNonStop packet"));
3906   return SendOKResponse();
3907 }
3908 
3909 GDBRemoteCommunication::PacketResult
3910 GDBRemoteCommunicationServerLLGS::Handle_vStopped(
3911     StringExtractorGDBRemote &packet) {
3912   // Per the protocol, the first message put into the queue is sent
3913   // immediately.  However, it remains the queue until the client ACKs
3914   // it via vStopped -- then we pop it and send the next message.
3915   // The process repeats until the last message in the queue is ACK-ed,
3916   // in which case the vStopped packet sends an OK response.
3917 
3918   if (m_stop_notification_queue.empty())
3919     return SendErrorResponse(Status("No pending notification to ack"));
3920   m_stop_notification_queue.pop_front();
3921   if (!m_stop_notification_queue.empty())
3922     return SendPacketNoLock(m_stop_notification_queue.front());
3923   // If this was the last notification and all the processes exited,
3924   // terminate the server.
3925   if (m_debugged_processes.empty()) {
3926     m_exit_now = true;
3927     m_mainloop.RequestTermination();
3928   }
3929   return SendOKResponse();
3930 }
3931 
3932 GDBRemoteCommunication::PacketResult
3933 GDBRemoteCommunicationServerLLGS::Handle_vCtrlC(
3934     StringExtractorGDBRemote &packet) {
3935   if (!m_non_stop)
3936     return SendErrorResponse(Status("vCtrl is only valid in non-stop mode"));
3937 
3938   PacketResult interrupt_res = Handle_interrupt(packet);
3939   // If interrupting the process failed, pass the result through.
3940   if (interrupt_res != PacketResult::Success)
3941     return interrupt_res;
3942   // Otherwise, vCtrlC should issue an OK response (normal interrupts do not).
3943   return SendOKResponse();
3944 }
3945 
3946 GDBRemoteCommunication::PacketResult
3947 GDBRemoteCommunicationServerLLGS::Handle_T(StringExtractorGDBRemote &packet) {
3948   packet.SetFilePos(strlen("T"));
3949   auto pid_tid = packet.GetPidTid(m_current_process ? m_current_process->GetID()
3950                                                     : LLDB_INVALID_PROCESS_ID);
3951   if (!pid_tid)
3952     return SendErrorResponse(llvm::make_error<StringError>(
3953         inconvertibleErrorCode(), "Malformed thread-id"));
3954 
3955   lldb::pid_t pid = pid_tid->first;
3956   lldb::tid_t tid = pid_tid->second;
3957 
3958   // Technically, this would also be caught by the PID check but let's be more
3959   // explicit about the error.
3960   if (pid == LLDB_INVALID_PROCESS_ID)
3961     return SendErrorResponse(llvm::make_error<StringError>(
3962         inconvertibleErrorCode(), "No current process and no PID provided"));
3963 
3964   // Check the process ID and find respective process instance.
3965   auto new_process_it = m_debugged_processes.find(pid);
3966   if (new_process_it == m_debugged_processes.end())
3967     return SendErrorResponse(1);
3968 
3969   // Check the thread ID
3970   if (!new_process_it->second.process_up->GetThreadByID(tid))
3971     return SendErrorResponse(2);
3972 
3973   return SendOKResponse();
3974 }
3975 
3976 void GDBRemoteCommunicationServerLLGS::MaybeCloseInferiorTerminalConnection() {
3977   Log *log = GetLog(LLDBLog::Process);
3978 
3979   // Tell the stdio connection to shut down.
3980   if (m_stdio_communication.IsConnected()) {
3981     auto connection = m_stdio_communication.GetConnection();
3982     if (connection) {
3983       Status error;
3984       connection->Disconnect(&error);
3985 
3986       if (error.Success()) {
3987         LLDB_LOGF(log,
3988                   "GDBRemoteCommunicationServerLLGS::%s disconnect process "
3989                   "terminal stdio - SUCCESS",
3990                   __FUNCTION__);
3991       } else {
3992         LLDB_LOGF(log,
3993                   "GDBRemoteCommunicationServerLLGS::%s disconnect process "
3994                   "terminal stdio - FAIL: %s",
3995                   __FUNCTION__, error.AsCString());
3996       }
3997     }
3998   }
3999 }
4000 
4001 NativeThreadProtocol *GDBRemoteCommunicationServerLLGS::GetThreadFromSuffix(
4002     StringExtractorGDBRemote &packet) {
4003   // We have no thread if we don't have a process.
4004   if (!m_current_process ||
4005       m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)
4006     return nullptr;
4007 
4008   // If the client hasn't asked for thread suffix support, there will not be a
4009   // thread suffix. Use the current thread in that case.
4010   if (!m_thread_suffix_supported) {
4011     const lldb::tid_t current_tid = GetCurrentThreadID();
4012     if (current_tid == LLDB_INVALID_THREAD_ID)
4013       return nullptr;
4014     else if (current_tid == 0) {
4015       // Pick a thread.
4016       return m_current_process->GetThreadAtIndex(0);
4017     } else
4018       return m_current_process->GetThreadByID(current_tid);
4019   }
4020 
4021   Log *log = GetLog(LLDBLog::Thread);
4022 
4023   // Parse out the ';'.
4024   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ';') {
4025     LLDB_LOGF(log,
4026               "GDBRemoteCommunicationServerLLGS::%s gdb-remote parse "
4027               "error: expected ';' prior to start of thread suffix: packet "
4028               "contents = '%s'",
4029               __FUNCTION__, packet.GetStringRef().data());
4030     return nullptr;
4031   }
4032 
4033   if (!packet.GetBytesLeft())
4034     return nullptr;
4035 
4036   // Parse out thread: portion.
4037   if (strncmp(packet.Peek(), "thread:", strlen("thread:")) != 0) {
4038     LLDB_LOGF(log,
4039               "GDBRemoteCommunicationServerLLGS::%s gdb-remote parse "
4040               "error: expected 'thread:' but not found, packet contents = "
4041               "'%s'",
4042               __FUNCTION__, packet.GetStringRef().data());
4043     return nullptr;
4044   }
4045   packet.SetFilePos(packet.GetFilePos() + strlen("thread:"));
4046   const lldb::tid_t tid = packet.GetHexMaxU64(false, 0);
4047   if (tid != 0)
4048     return m_current_process->GetThreadByID(tid);
4049 
4050   return nullptr;
4051 }
4052 
4053 lldb::tid_t GDBRemoteCommunicationServerLLGS::GetCurrentThreadID() const {
4054   if (m_current_tid == 0 || m_current_tid == LLDB_INVALID_THREAD_ID) {
4055     // Use whatever the debug process says is the current thread id since the
4056     // protocol either didn't specify or specified we want any/all threads
4057     // marked as the current thread.
4058     if (!m_current_process)
4059       return LLDB_INVALID_THREAD_ID;
4060     return m_current_process->GetCurrentThreadID();
4061   }
4062   // Use the specific current thread id set by the gdb remote protocol.
4063   return m_current_tid;
4064 }
4065 
4066 uint32_t GDBRemoteCommunicationServerLLGS::GetNextSavedRegistersID() {
4067   std::lock_guard<std::mutex> guard(m_saved_registers_mutex);
4068   return m_next_saved_registers_id++;
4069 }
4070 
4071 void GDBRemoteCommunicationServerLLGS::ClearProcessSpecificData() {
4072   Log *log = GetLog(LLDBLog::Process);
4073 
4074   LLDB_LOG(log, "clearing {0} xfer buffers", m_xfer_buffer_map.size());
4075   m_xfer_buffer_map.clear();
4076 }
4077 
4078 FileSpec
4079 GDBRemoteCommunicationServerLLGS::FindModuleFile(const std::string &module_path,
4080                                                  const ArchSpec &arch) {
4081   if (m_current_process) {
4082     FileSpec file_spec;
4083     if (m_current_process
4084             ->GetLoadedModuleFileSpec(module_path.c_str(), file_spec)
4085             .Success()) {
4086       if (FileSystem::Instance().Exists(file_spec))
4087         return file_spec;
4088     }
4089   }
4090 
4091   return GDBRemoteCommunicationServerCommon::FindModuleFile(module_path, arch);
4092 }
4093 
4094 std::string GDBRemoteCommunicationServerLLGS::XMLEncodeAttributeValue(
4095     llvm::StringRef value) {
4096   std::string result;
4097   for (const char &c : value) {
4098     switch (c) {
4099     case '\'':
4100       result += "&apos;";
4101       break;
4102     case '"':
4103       result += "&quot;";
4104       break;
4105     case '<':
4106       result += "&lt;";
4107       break;
4108     case '>':
4109       result += "&gt;";
4110       break;
4111     default:
4112       result += c;
4113       break;
4114     }
4115   }
4116   return result;
4117 }
4118 
4119 std::vector<std::string> GDBRemoteCommunicationServerLLGS::HandleFeatures(
4120     const llvm::ArrayRef<llvm::StringRef> client_features) {
4121   std::vector<std::string> ret =
4122       GDBRemoteCommunicationServerCommon::HandleFeatures(client_features);
4123   ret.insert(ret.end(), {
4124                             "QThreadSuffixSupported+",
4125                             "QListThreadsInStopReply+",
4126                             "qXfer:features:read+",
4127                             "QNonStop+",
4128                         });
4129 
4130   // report server-only features
4131   using Extension = NativeProcessProtocol::Extension;
4132   Extension plugin_features = m_process_factory.GetSupportedExtensions();
4133   if (bool(plugin_features & Extension::pass_signals))
4134     ret.push_back("QPassSignals+");
4135   if (bool(plugin_features & Extension::auxv))
4136     ret.push_back("qXfer:auxv:read+");
4137   if (bool(plugin_features & Extension::libraries_svr4))
4138     ret.push_back("qXfer:libraries-svr4:read+");
4139   if (bool(plugin_features & Extension::siginfo_read))
4140     ret.push_back("qXfer:siginfo:read+");
4141   if (bool(plugin_features & Extension::memory_tagging))
4142     ret.push_back("memory-tagging+");
4143   if (bool(plugin_features & Extension::savecore))
4144     ret.push_back("qSaveCore+");
4145 
4146   // check for client features
4147   m_extensions_supported = {};
4148   for (llvm::StringRef x : client_features)
4149     m_extensions_supported |=
4150         llvm::StringSwitch<Extension>(x)
4151             .Case("multiprocess+", Extension::multiprocess)
4152             .Case("fork-events+", Extension::fork)
4153             .Case("vfork-events+", Extension::vfork)
4154             .Default({});
4155 
4156   m_extensions_supported &= plugin_features;
4157 
4158   // fork & vfork require multiprocess
4159   if (!bool(m_extensions_supported & Extension::multiprocess))
4160     m_extensions_supported &= ~(Extension::fork | Extension::vfork);
4161 
4162   // report only if actually supported
4163   if (bool(m_extensions_supported & Extension::multiprocess))
4164     ret.push_back("multiprocess+");
4165   if (bool(m_extensions_supported & Extension::fork))
4166     ret.push_back("fork-events+");
4167   if (bool(m_extensions_supported & Extension::vfork))
4168     ret.push_back("vfork-events+");
4169 
4170   for (auto &x : m_debugged_processes)
4171     SetEnabledExtensions(*x.second.process_up);
4172   return ret;
4173 }
4174 
4175 void GDBRemoteCommunicationServerLLGS::SetEnabledExtensions(
4176     NativeProcessProtocol &process) {
4177   NativeProcessProtocol::Extension flags = m_extensions_supported;
4178   assert(!bool(flags & ~m_process_factory.GetSupportedExtensions()));
4179   process.SetEnabledExtensions(flags);
4180 }
4181 
4182 GDBRemoteCommunication::PacketResult
4183 GDBRemoteCommunicationServerLLGS::SendContinueSuccessResponse() {
4184   // TODO: how to handle forwarding in non-stop mode?
4185   StartSTDIOForwarding();
4186   return m_non_stop ? SendOKResponse() : PacketResult::Success;
4187 }
4188 
4189 void GDBRemoteCommunicationServerLLGS::AppendThreadIDToResponse(
4190     Stream &response, lldb::pid_t pid, lldb::tid_t tid) {
4191   if (bool(m_extensions_supported &
4192            NativeProcessProtocol::Extension::multiprocess))
4193     response.Format("p{0:x-}.", pid);
4194   response.Format("{0:x-}", tid);
4195 }
4196 
4197 std::string
4198 lldb_private::process_gdb_remote::LLGSArgToURL(llvm::StringRef url_arg,
4199                                                bool reverse_connect) {
4200   // Try parsing the argument as URL.
4201   if (llvm::Optional<URI> url = URI::Parse(url_arg)) {
4202     if (reverse_connect)
4203       return url_arg.str();
4204 
4205     // Translate the scheme from LLGS notation to ConnectionFileDescriptor.
4206     // If the scheme doesn't match any, pass it through to support using CFD
4207     // schemes directly.
4208     std::string new_url = llvm::StringSwitch<std::string>(url->scheme)
4209                               .Case("tcp", "listen")
4210                               .Case("unix", "unix-accept")
4211                               .Case("unix-abstract", "unix-abstract-accept")
4212                               .Default(url->scheme.str());
4213     llvm::append_range(new_url, url_arg.substr(url->scheme.size()));
4214     return new_url;
4215   }
4216 
4217   std::string host_port = url_arg.str();
4218   // If host_and_port starts with ':', default the host to be "localhost" and
4219   // expect the remainder to be the port.
4220   if (url_arg.startswith(":"))
4221     host_port.insert(0, "localhost");
4222 
4223   // Try parsing the (preprocessed) argument as host:port pair.
4224   if (!llvm::errorToBool(Socket::DecodeHostAndPort(host_port).takeError()))
4225     return (reverse_connect ? "connect://" : "listen://") + host_port;
4226 
4227   // If none of the above applied, interpret the argument as UNIX socket path.
4228   return (reverse_connect ? "unix-connect://" : "unix-accept://") +
4229          url_arg.str();
4230 }
4231