xref: /llvm-project/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp (revision 7a2b09b4798dbd5ec69e934b595eab5afddf33c5)
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::Handle_C(StringExtractorGDBRemote &packet) {
1517   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
1518   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s called", __FUNCTION__);
1519 
1520   // Ensure we have a native process.
1521   if (!m_continue_process) {
1522     LLDB_LOGF(log,
1523               "GDBRemoteCommunicationServerLLGS::%s no debugged process "
1524               "shared pointer",
1525               __FUNCTION__);
1526     return SendErrorResponse(0x36);
1527   }
1528 
1529   // Pull out the signal number.
1530   packet.SetFilePos(::strlen("C"));
1531   if (packet.GetBytesLeft() < 1) {
1532     // Shouldn't be using a C without a signal.
1533     return SendIllFormedResponse(packet, "C packet specified without signal.");
1534   }
1535   const uint32_t signo =
1536       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
1537   if (signo == std::numeric_limits<uint32_t>::max())
1538     return SendIllFormedResponse(packet, "failed to parse signal number");
1539 
1540   // Handle optional continue address.
1541   if (packet.GetBytesLeft() > 0) {
1542     // FIXME add continue at address support for $C{signo}[;{continue-address}].
1543     if (*packet.Peek() == ';')
1544       return SendUnimplementedResponse(packet.GetStringRef().data());
1545     else
1546       return SendIllFormedResponse(
1547           packet, "unexpected content after $C{signal-number}");
1548   }
1549 
1550   ResumeActionList resume_actions(StateType::eStateRunning,
1551                                   LLDB_INVALID_SIGNAL_NUMBER);
1552   Status error;
1553 
1554   // We have two branches: what to do if a continue thread is specified (in
1555   // which case we target sending the signal to that thread), or when we don't
1556   // have a continue thread set (in which case we send a signal to the
1557   // process).
1558 
1559   // TODO discuss with Greg Clayton, make sure this makes sense.
1560 
1561   lldb::tid_t signal_tid = GetContinueThreadID();
1562   if (signal_tid != LLDB_INVALID_THREAD_ID) {
1563     // The resume action for the continue thread (or all threads if a continue
1564     // thread is not set).
1565     ResumeAction action = {GetContinueThreadID(), StateType::eStateRunning,
1566                            static_cast<int>(signo)};
1567 
1568     // Add the action for the continue thread (or all threads when the continue
1569     // thread isn't present).
1570     resume_actions.Append(action);
1571   } else {
1572     // Send the signal to the process since we weren't targeting a specific
1573     // continue thread with the signal.
1574     error = m_continue_process->Signal(signo);
1575     if (error.Fail()) {
1576       LLDB_LOG(log, "failed to send signal for process {0}: {1}",
1577                m_continue_process->GetID(), error);
1578 
1579       return SendErrorResponse(0x52);
1580     }
1581   }
1582 
1583   // Resume the threads.
1584   error = m_continue_process->Resume(resume_actions);
1585   if (error.Fail()) {
1586     LLDB_LOG(log, "failed to resume threads for process {0}: {1}",
1587              m_continue_process->GetID(), error);
1588 
1589     return SendErrorResponse(0x38);
1590   }
1591 
1592   // Don't send an "OK" packet, except in non-stop mode;
1593   // otherwise, the response is the stopped/exited message.
1594   return SendContinueSuccessResponse();
1595 }
1596 
1597 GDBRemoteCommunication::PacketResult
1598 GDBRemoteCommunicationServerLLGS::Handle_c(StringExtractorGDBRemote &packet) {
1599   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
1600   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s called", __FUNCTION__);
1601 
1602   packet.SetFilePos(packet.GetFilePos() + ::strlen("c"));
1603 
1604   // For now just support all continue.
1605   const bool has_continue_address = (packet.GetBytesLeft() > 0);
1606   if (has_continue_address) {
1607     LLDB_LOG(log, "not implemented for c[address] variant [{0} remains]",
1608              packet.Peek());
1609     return SendUnimplementedResponse(packet.GetStringRef().data());
1610   }
1611 
1612   // Ensure we have a native process.
1613   if (!m_continue_process) {
1614     LLDB_LOGF(log,
1615               "GDBRemoteCommunicationServerLLGS::%s no debugged process "
1616               "shared pointer",
1617               __FUNCTION__);
1618     return SendErrorResponse(0x36);
1619   }
1620 
1621   // Build the ResumeActionList
1622   ResumeActionList actions(StateType::eStateRunning,
1623                            LLDB_INVALID_SIGNAL_NUMBER);
1624 
1625   Status error = m_continue_process->Resume(actions);
1626   if (error.Fail()) {
1627     LLDB_LOG(log, "c failed for process {0}: {1}", m_continue_process->GetID(),
1628              error);
1629     return SendErrorResponse(GDBRemoteServerError::eErrorResume);
1630   }
1631 
1632   LLDB_LOG(log, "continued process {0}", m_continue_process->GetID());
1633 
1634   return SendContinueSuccessResponse();
1635 }
1636 
1637 GDBRemoteCommunication::PacketResult
1638 GDBRemoteCommunicationServerLLGS::Handle_vCont_actions(
1639     StringExtractorGDBRemote &packet) {
1640   StreamString response;
1641   response.Printf("vCont;c;C;s;S;t");
1642 
1643   return SendPacketNoLock(response.GetString());
1644 }
1645 
1646 GDBRemoteCommunication::PacketResult
1647 GDBRemoteCommunicationServerLLGS::Handle_vCont(
1648     StringExtractorGDBRemote &packet) {
1649   Log *log = GetLog(LLDBLog::Process);
1650   LLDB_LOGF(log, "GDBRemoteCommunicationServerLLGS::%s handling vCont packet",
1651             __FUNCTION__);
1652 
1653   packet.SetFilePos(::strlen("vCont"));
1654 
1655   if (packet.GetBytesLeft() == 0) {
1656     LLDB_LOGF(log,
1657               "GDBRemoteCommunicationServerLLGS::%s missing action from "
1658               "vCont package",
1659               __FUNCTION__);
1660     return SendIllFormedResponse(packet, "Missing action from vCont package");
1661   }
1662 
1663   if (::strcmp(packet.Peek(), ";s") == 0) {
1664     // Move past the ';', then do a simple 's'.
1665     packet.SetFilePos(packet.GetFilePos() + 1);
1666     return Handle_s(packet);
1667   } else if (m_non_stop && ::strcmp(packet.Peek(), ";t") == 0) {
1668     // TODO: add full support for "t" action
1669     return SendOKResponse();
1670   }
1671 
1672   std::unordered_map<lldb::pid_t, ResumeActionList> thread_actions;
1673 
1674   while (packet.GetBytesLeft() && *packet.Peek() == ';') {
1675     // Skip the semi-colon.
1676     packet.GetChar();
1677 
1678     // Build up the thread action.
1679     ResumeAction thread_action;
1680     thread_action.tid = LLDB_INVALID_THREAD_ID;
1681     thread_action.state = eStateInvalid;
1682     thread_action.signal = LLDB_INVALID_SIGNAL_NUMBER;
1683 
1684     const char action = packet.GetChar();
1685     switch (action) {
1686     case 'C':
1687       thread_action.signal = packet.GetHexMaxU32(false, 0);
1688       if (thread_action.signal == 0)
1689         return SendIllFormedResponse(
1690             packet, "Could not parse signal in vCont packet C action");
1691       LLVM_FALLTHROUGH;
1692 
1693     case 'c':
1694       // Continue
1695       thread_action.state = eStateRunning;
1696       break;
1697 
1698     case 'S':
1699       thread_action.signal = packet.GetHexMaxU32(false, 0);
1700       if (thread_action.signal == 0)
1701         return SendIllFormedResponse(
1702             packet, "Could not parse signal in vCont packet S action");
1703       LLVM_FALLTHROUGH;
1704 
1705     case 's':
1706       // Step
1707       thread_action.state = eStateStepping;
1708       break;
1709 
1710     case 't':
1711       // Stop
1712       thread_action.state = eStateSuspended;
1713       break;
1714 
1715     default:
1716       return SendIllFormedResponse(packet, "Unsupported vCont action");
1717       break;
1718     }
1719 
1720     lldb::pid_t pid = StringExtractorGDBRemote::AllProcesses;
1721     lldb::tid_t tid = StringExtractorGDBRemote::AllThreads;
1722 
1723     // Parse out optional :{thread-id} value.
1724     if (packet.GetBytesLeft() && (*packet.Peek() == ':')) {
1725       // Consume the separator.
1726       packet.GetChar();
1727 
1728       auto pid_tid = packet.GetPidTid(StringExtractorGDBRemote::AllProcesses);
1729       if (!pid_tid)
1730         return SendIllFormedResponse(packet, "Malformed thread-id");
1731 
1732       pid = pid_tid->first;
1733       tid = pid_tid->second;
1734     }
1735 
1736     if (pid == StringExtractorGDBRemote::AllProcesses) {
1737       if (m_debugged_processes.size() > 1)
1738         return SendIllFormedResponse(
1739             packet, "Resuming multiple processes not supported yet");
1740       if (!m_continue_process) {
1741         LLDB_LOG(log, "no debugged process");
1742         return SendErrorResponse(0x36);
1743       }
1744       pid = m_continue_process->GetID();
1745     }
1746 
1747     if (tid == StringExtractorGDBRemote::AllThreads)
1748       tid = LLDB_INVALID_THREAD_ID;
1749 
1750     thread_action.tid = tid;
1751 
1752     thread_actions[pid].Append(thread_action);
1753   }
1754 
1755   assert(thread_actions.size() >= 1);
1756   if (thread_actions.size() > 1)
1757     return SendIllFormedResponse(
1758         packet, "Resuming multiple processes not supported yet");
1759 
1760   for (std::pair<lldb::pid_t, ResumeActionList> x : thread_actions) {
1761     auto process_it = m_debugged_processes.find(x.first);
1762     if (process_it == m_debugged_processes.end()) {
1763       LLDB_LOG(log, "vCont failed for process {0}: process not debugged",
1764                x.first);
1765       return SendErrorResponse(GDBRemoteServerError::eErrorResume);
1766     }
1767 
1768     Status error = process_it->second.process_up->Resume(x.second);
1769     if (error.Fail()) {
1770       LLDB_LOG(log, "vCont failed for process {0}: {1}", x.first, error);
1771       return SendErrorResponse(GDBRemoteServerError::eErrorResume);
1772     }
1773 
1774     LLDB_LOG(log, "continued process {0}", x.first);
1775   }
1776 
1777   return SendContinueSuccessResponse();
1778 }
1779 
1780 void GDBRemoteCommunicationServerLLGS::SetCurrentThreadID(lldb::tid_t tid) {
1781   Log *log = GetLog(LLDBLog::Thread);
1782   LLDB_LOG(log, "setting current thread id to {0}", tid);
1783 
1784   m_current_tid = tid;
1785   if (m_current_process)
1786     m_current_process->SetCurrentThreadID(m_current_tid);
1787 }
1788 
1789 void GDBRemoteCommunicationServerLLGS::SetContinueThreadID(lldb::tid_t tid) {
1790   Log *log = GetLog(LLDBLog::Thread);
1791   LLDB_LOG(log, "setting continue thread id to {0}", tid);
1792 
1793   m_continue_tid = tid;
1794 }
1795 
1796 GDBRemoteCommunication::PacketResult
1797 GDBRemoteCommunicationServerLLGS::Handle_stop_reason(
1798     StringExtractorGDBRemote &packet) {
1799   // Handle the $? gdbremote command.
1800 
1801   if (m_non_stop) {
1802     // Clear the notification queue first, except for pending exit
1803     // notifications.
1804     llvm::erase_if(m_stop_notification_queue, [](const std::string &x) {
1805       return x.front() != 'W' && x.front() != 'X';
1806     });
1807 
1808     if (m_current_process) {
1809       // Queue stop reply packets for all active threads.  Start with
1810       // the current thread (for clients that don't actually support multiple
1811       // stop reasons).
1812       NativeThreadProtocol *thread = m_current_process->GetCurrentThread();
1813       if (thread)
1814         m_stop_notification_queue.push_back(
1815             PrepareStopReplyPacketForThread(*thread).GetString().str());
1816       EnqueueStopReplyPackets(thread ? thread->GetID()
1817                                      : LLDB_INVALID_THREAD_ID);
1818     }
1819 
1820     // If the notification queue is empty (i.e. everything is running), send OK.
1821     if (m_stop_notification_queue.empty())
1822       return SendOKResponse();
1823 
1824     // Send the first item from the new notification queue synchronously.
1825     return SendPacketNoLock(m_stop_notification_queue.front());
1826   }
1827 
1828   // If no process, indicate error
1829   if (!m_current_process)
1830     return SendErrorResponse(02);
1831 
1832   return SendStopReasonForState(*m_current_process,
1833                                 m_current_process->GetState(),
1834                                 /*force_synchronous=*/true);
1835 }
1836 
1837 GDBRemoteCommunication::PacketResult
1838 GDBRemoteCommunicationServerLLGS::SendStopReasonForState(
1839     NativeProcessProtocol &process, lldb::StateType process_state,
1840     bool force_synchronous) {
1841   Log *log = GetLog(LLDBLog::Process);
1842 
1843   switch (process_state) {
1844   case eStateAttaching:
1845   case eStateLaunching:
1846   case eStateRunning:
1847   case eStateStepping:
1848   case eStateDetached:
1849     // NOTE: gdb protocol doc looks like it should return $OK
1850     // when everything is running (i.e. no stopped result).
1851     return PacketResult::Success; // Ignore
1852 
1853   case eStateSuspended:
1854   case eStateStopped:
1855   case eStateCrashed: {
1856     lldb::tid_t tid = process.GetCurrentThreadID();
1857     // Make sure we set the current thread so g and p packets return the data
1858     // the gdb will expect.
1859     SetCurrentThreadID(tid);
1860     return SendStopReplyPacketForThread(process, tid, force_synchronous);
1861   }
1862 
1863   case eStateInvalid:
1864   case eStateUnloaded:
1865   case eStateExited:
1866     return SendWResponse(&process);
1867 
1868   default:
1869     LLDB_LOG(log, "pid {0}, current state reporting not handled: {1}",
1870              process.GetID(), process_state);
1871     break;
1872   }
1873 
1874   return SendErrorResponse(0);
1875 }
1876 
1877 GDBRemoteCommunication::PacketResult
1878 GDBRemoteCommunicationServerLLGS::Handle_qRegisterInfo(
1879     StringExtractorGDBRemote &packet) {
1880   // Fail if we don't have a current process.
1881   if (!m_current_process ||
1882       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
1883     return SendErrorResponse(68);
1884 
1885   // Ensure we have a thread.
1886   NativeThreadProtocol *thread = m_current_process->GetThreadAtIndex(0);
1887   if (!thread)
1888     return SendErrorResponse(69);
1889 
1890   // Get the register context for the first thread.
1891   NativeRegisterContext &reg_context = thread->GetRegisterContext();
1892 
1893   // Parse out the register number from the request.
1894   packet.SetFilePos(strlen("qRegisterInfo"));
1895   const uint32_t reg_index =
1896       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
1897   if (reg_index == std::numeric_limits<uint32_t>::max())
1898     return SendErrorResponse(69);
1899 
1900   // Return the end of registers response if we've iterated one past the end of
1901   // the register set.
1902   if (reg_index >= reg_context.GetUserRegisterCount())
1903     return SendErrorResponse(69);
1904 
1905   const RegisterInfo *reg_info = reg_context.GetRegisterInfoAtIndex(reg_index);
1906   if (!reg_info)
1907     return SendErrorResponse(69);
1908 
1909   // Build the reginfos response.
1910   StreamGDBRemote response;
1911 
1912   response.PutCString("name:");
1913   response.PutCString(reg_info->name);
1914   response.PutChar(';');
1915 
1916   if (reg_info->alt_name && reg_info->alt_name[0]) {
1917     response.PutCString("alt-name:");
1918     response.PutCString(reg_info->alt_name);
1919     response.PutChar(';');
1920   }
1921 
1922   response.Printf("bitsize:%" PRIu32 ";", reg_info->byte_size * 8);
1923 
1924   if (!reg_context.RegisterOffsetIsDynamic())
1925     response.Printf("offset:%" PRIu32 ";", reg_info->byte_offset);
1926 
1927   llvm::StringRef encoding = GetEncodingNameOrEmpty(*reg_info);
1928   if (!encoding.empty())
1929     response << "encoding:" << encoding << ';';
1930 
1931   llvm::StringRef format = GetFormatNameOrEmpty(*reg_info);
1932   if (!format.empty())
1933     response << "format:" << format << ';';
1934 
1935   const char *const register_set_name =
1936       reg_context.GetRegisterSetNameForRegisterAtIndex(reg_index);
1937   if (register_set_name)
1938     response << "set:" << register_set_name << ';';
1939 
1940   if (reg_info->kinds[RegisterKind::eRegisterKindEHFrame] !=
1941       LLDB_INVALID_REGNUM)
1942     response.Printf("ehframe:%" PRIu32 ";",
1943                     reg_info->kinds[RegisterKind::eRegisterKindEHFrame]);
1944 
1945   if (reg_info->kinds[RegisterKind::eRegisterKindDWARF] != LLDB_INVALID_REGNUM)
1946     response.Printf("dwarf:%" PRIu32 ";",
1947                     reg_info->kinds[RegisterKind::eRegisterKindDWARF]);
1948 
1949   llvm::StringRef kind_generic = GetKindGenericOrEmpty(*reg_info);
1950   if (!kind_generic.empty())
1951     response << "generic:" << kind_generic << ';';
1952 
1953   if (reg_info->value_regs && reg_info->value_regs[0] != LLDB_INVALID_REGNUM) {
1954     response.PutCString("container-regs:");
1955     CollectRegNums(reg_info->value_regs, response, true);
1956     response.PutChar(';');
1957   }
1958 
1959   if (reg_info->invalidate_regs && reg_info->invalidate_regs[0]) {
1960     response.PutCString("invalidate-regs:");
1961     CollectRegNums(reg_info->invalidate_regs, response, true);
1962     response.PutChar(';');
1963   }
1964 
1965   return SendPacketNoLock(response.GetString());
1966 }
1967 
1968 void GDBRemoteCommunicationServerLLGS::AddProcessThreads(
1969     StreamGDBRemote &response, NativeProcessProtocol &process, bool &had_any) {
1970   Log *log = GetLog(LLDBLog::Thread);
1971 
1972   lldb::pid_t pid = process.GetID();
1973   if (pid == LLDB_INVALID_PROCESS_ID)
1974     return;
1975 
1976   LLDB_LOG(log, "iterating over threads of process {0}", process.GetID());
1977   for (NativeThreadProtocol &thread : process.Threads()) {
1978     LLDB_LOG(log, "iterated thread tid={0}", thread.GetID());
1979     response.PutChar(had_any ? ',' : 'm');
1980     AppendThreadIDToResponse(response, pid, thread.GetID());
1981     had_any = true;
1982   }
1983 }
1984 
1985 GDBRemoteCommunication::PacketResult
1986 GDBRemoteCommunicationServerLLGS::Handle_qfThreadInfo(
1987     StringExtractorGDBRemote &packet) {
1988   assert(m_debugged_processes.size() == 1 ||
1989          bool(m_extensions_supported &
1990               NativeProcessProtocol::Extension::multiprocess));
1991 
1992   bool had_any = false;
1993   StreamGDBRemote response;
1994 
1995   for (auto &pid_ptr : m_debugged_processes)
1996     AddProcessThreads(response, *pid_ptr.second.process_up, had_any);
1997 
1998   if (!had_any)
1999     return SendOKResponse();
2000   return SendPacketNoLock(response.GetString());
2001 }
2002 
2003 GDBRemoteCommunication::PacketResult
2004 GDBRemoteCommunicationServerLLGS::Handle_qsThreadInfo(
2005     StringExtractorGDBRemote &packet) {
2006   // FIXME for now we return the full thread list in the initial packet and
2007   // always do nothing here.
2008   return SendPacketNoLock("l");
2009 }
2010 
2011 GDBRemoteCommunication::PacketResult
2012 GDBRemoteCommunicationServerLLGS::Handle_g(StringExtractorGDBRemote &packet) {
2013   Log *log = GetLog(LLDBLog::Thread);
2014 
2015   // Move past packet name.
2016   packet.SetFilePos(strlen("g"));
2017 
2018   // Get the thread to use.
2019   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
2020   if (!thread) {
2021     LLDB_LOG(log, "failed, no thread available");
2022     return SendErrorResponse(0x15);
2023   }
2024 
2025   // Get the thread's register context.
2026   NativeRegisterContext &reg_ctx = thread->GetRegisterContext();
2027 
2028   std::vector<uint8_t> regs_buffer;
2029   for (uint32_t reg_num = 0; reg_num < reg_ctx.GetUserRegisterCount();
2030        ++reg_num) {
2031     const RegisterInfo *reg_info = reg_ctx.GetRegisterInfoAtIndex(reg_num);
2032 
2033     if (reg_info == nullptr) {
2034       LLDB_LOG(log, "failed to get register info for register index {0}",
2035                reg_num);
2036       return SendErrorResponse(0x15);
2037     }
2038 
2039     if (reg_info->value_regs != nullptr)
2040       continue; // skip registers that are contained in other registers
2041 
2042     RegisterValue reg_value;
2043     Status error = reg_ctx.ReadRegister(reg_info, reg_value);
2044     if (error.Fail()) {
2045       LLDB_LOG(log, "failed to read register at index {0}", reg_num);
2046       return SendErrorResponse(0x15);
2047     }
2048 
2049     if (reg_info->byte_offset + reg_info->byte_size >= regs_buffer.size())
2050       // Resize the buffer to guarantee it can store the register offsetted
2051       // data.
2052       regs_buffer.resize(reg_info->byte_offset + reg_info->byte_size);
2053 
2054     // Copy the register offsetted data to the buffer.
2055     memcpy(regs_buffer.data() + reg_info->byte_offset, reg_value.GetBytes(),
2056            reg_info->byte_size);
2057   }
2058 
2059   // Write the response.
2060   StreamGDBRemote response;
2061   response.PutBytesAsRawHex8(regs_buffer.data(), regs_buffer.size());
2062 
2063   return SendPacketNoLock(response.GetString());
2064 }
2065 
2066 GDBRemoteCommunication::PacketResult
2067 GDBRemoteCommunicationServerLLGS::Handle_p(StringExtractorGDBRemote &packet) {
2068   Log *log = GetLog(LLDBLog::Thread);
2069 
2070   // Parse out the register number from the request.
2071   packet.SetFilePos(strlen("p"));
2072   const uint32_t reg_index =
2073       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
2074   if (reg_index == std::numeric_limits<uint32_t>::max()) {
2075     LLDB_LOGF(log,
2076               "GDBRemoteCommunicationServerLLGS::%s failed, could not "
2077               "parse register number from request \"%s\"",
2078               __FUNCTION__, packet.GetStringRef().data());
2079     return SendErrorResponse(0x15);
2080   }
2081 
2082   // Get the thread to use.
2083   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
2084   if (!thread) {
2085     LLDB_LOG(log, "failed, no thread available");
2086     return SendErrorResponse(0x15);
2087   }
2088 
2089   // Get the thread's register context.
2090   NativeRegisterContext &reg_context = thread->GetRegisterContext();
2091 
2092   // Return the end of registers response if we've iterated one past the end of
2093   // the register set.
2094   if (reg_index >= reg_context.GetUserRegisterCount()) {
2095     LLDB_LOGF(log,
2096               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2097               "register %" PRIu32 " beyond register count %" PRIu32,
2098               __FUNCTION__, reg_index, reg_context.GetUserRegisterCount());
2099     return SendErrorResponse(0x15);
2100   }
2101 
2102   const RegisterInfo *reg_info = reg_context.GetRegisterInfoAtIndex(reg_index);
2103   if (!reg_info) {
2104     LLDB_LOGF(log,
2105               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2106               "register %" PRIu32 " returned NULL",
2107               __FUNCTION__, reg_index);
2108     return SendErrorResponse(0x15);
2109   }
2110 
2111   // Build the reginfos response.
2112   StreamGDBRemote response;
2113 
2114   // Retrieve the value
2115   RegisterValue reg_value;
2116   Status error = reg_context.ReadRegister(reg_info, reg_value);
2117   if (error.Fail()) {
2118     LLDB_LOGF(log,
2119               "GDBRemoteCommunicationServerLLGS::%s failed, read of "
2120               "requested register %" PRIu32 " (%s) failed: %s",
2121               __FUNCTION__, reg_index, reg_info->name, error.AsCString());
2122     return SendErrorResponse(0x15);
2123   }
2124 
2125   const uint8_t *const data =
2126       static_cast<const uint8_t *>(reg_value.GetBytes());
2127   if (!data) {
2128     LLDB_LOGF(log,
2129               "GDBRemoteCommunicationServerLLGS::%s failed to get data "
2130               "bytes from requested register %" PRIu32,
2131               __FUNCTION__, reg_index);
2132     return SendErrorResponse(0x15);
2133   }
2134 
2135   // FIXME flip as needed to get data in big/little endian format for this host.
2136   for (uint32_t i = 0; i < reg_value.GetByteSize(); ++i)
2137     response.PutHex8(data[i]);
2138 
2139   return SendPacketNoLock(response.GetString());
2140 }
2141 
2142 GDBRemoteCommunication::PacketResult
2143 GDBRemoteCommunicationServerLLGS::Handle_P(StringExtractorGDBRemote &packet) {
2144   Log *log = GetLog(LLDBLog::Thread);
2145 
2146   // Ensure there is more content.
2147   if (packet.GetBytesLeft() < 1)
2148     return SendIllFormedResponse(packet, "Empty P packet");
2149 
2150   // Parse out the register number from the request.
2151   packet.SetFilePos(strlen("P"));
2152   const uint32_t reg_index =
2153       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
2154   if (reg_index == std::numeric_limits<uint32_t>::max()) {
2155     LLDB_LOGF(log,
2156               "GDBRemoteCommunicationServerLLGS::%s failed, could not "
2157               "parse register number from request \"%s\"",
2158               __FUNCTION__, packet.GetStringRef().data());
2159     return SendErrorResponse(0x29);
2160   }
2161 
2162   // Note debugserver would send an E30 here.
2163   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != '='))
2164     return SendIllFormedResponse(
2165         packet, "P packet missing '=' char after register number");
2166 
2167   // Parse out the value.
2168   uint8_t reg_bytes[RegisterValue::kMaxRegisterByteSize];
2169   size_t reg_size = packet.GetHexBytesAvail(reg_bytes);
2170 
2171   // Get the thread to use.
2172   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
2173   if (!thread) {
2174     LLDB_LOGF(log,
2175               "GDBRemoteCommunicationServerLLGS::%s failed, no thread "
2176               "available (thread index 0)",
2177               __FUNCTION__);
2178     return SendErrorResponse(0x28);
2179   }
2180 
2181   // Get the thread's register context.
2182   NativeRegisterContext &reg_context = thread->GetRegisterContext();
2183   const RegisterInfo *reg_info = reg_context.GetRegisterInfoAtIndex(reg_index);
2184   if (!reg_info) {
2185     LLDB_LOGF(log,
2186               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2187               "register %" PRIu32 " returned NULL",
2188               __FUNCTION__, reg_index);
2189     return SendErrorResponse(0x48);
2190   }
2191 
2192   // Return the end of registers response if we've iterated one past the end of
2193   // the register set.
2194   if (reg_index >= reg_context.GetUserRegisterCount()) {
2195     LLDB_LOGF(log,
2196               "GDBRemoteCommunicationServerLLGS::%s failed, requested "
2197               "register %" PRIu32 " beyond register count %" PRIu32,
2198               __FUNCTION__, reg_index, reg_context.GetUserRegisterCount());
2199     return SendErrorResponse(0x47);
2200   }
2201 
2202   if (reg_size != reg_info->byte_size)
2203     return SendIllFormedResponse(packet, "P packet register size is incorrect");
2204 
2205   // Build the reginfos response.
2206   StreamGDBRemote response;
2207 
2208   RegisterValue reg_value(makeArrayRef(reg_bytes, reg_size),
2209                           m_current_process->GetArchitecture().GetByteOrder());
2210   Status error = reg_context.WriteRegister(reg_info, reg_value);
2211   if (error.Fail()) {
2212     LLDB_LOGF(log,
2213               "GDBRemoteCommunicationServerLLGS::%s failed, write of "
2214               "requested register %" PRIu32 " (%s) failed: %s",
2215               __FUNCTION__, reg_index, reg_info->name, error.AsCString());
2216     return SendErrorResponse(0x32);
2217   }
2218 
2219   return SendOKResponse();
2220 }
2221 
2222 GDBRemoteCommunication::PacketResult
2223 GDBRemoteCommunicationServerLLGS::Handle_H(StringExtractorGDBRemote &packet) {
2224   Log *log = GetLog(LLDBLog::Thread);
2225 
2226   // Parse out which variant of $H is requested.
2227   packet.SetFilePos(strlen("H"));
2228   if (packet.GetBytesLeft() < 1) {
2229     LLDB_LOGF(log,
2230               "GDBRemoteCommunicationServerLLGS::%s failed, H command "
2231               "missing {g,c} variant",
2232               __FUNCTION__);
2233     return SendIllFormedResponse(packet, "H command missing {g,c} variant");
2234   }
2235 
2236   const char h_variant = packet.GetChar();
2237   NativeProcessProtocol *default_process;
2238   switch (h_variant) {
2239   case 'g':
2240     default_process = m_current_process;
2241     break;
2242 
2243   case 'c':
2244     default_process = m_continue_process;
2245     break;
2246 
2247   default:
2248     LLDB_LOGF(
2249         log,
2250         "GDBRemoteCommunicationServerLLGS::%s failed, invalid $H variant %c",
2251         __FUNCTION__, h_variant);
2252     return SendIllFormedResponse(packet,
2253                                  "H variant unsupported, should be c or g");
2254   }
2255 
2256   // Parse out the thread number.
2257   auto pid_tid = packet.GetPidTid(default_process ? default_process->GetID()
2258                                                   : LLDB_INVALID_PROCESS_ID);
2259   if (!pid_tid)
2260     return SendErrorResponse(llvm::make_error<StringError>(
2261         inconvertibleErrorCode(), "Malformed thread-id"));
2262 
2263   lldb::pid_t pid = pid_tid->first;
2264   lldb::tid_t tid = pid_tid->second;
2265 
2266   if (pid == StringExtractorGDBRemote::AllProcesses)
2267     return SendUnimplementedResponse("Selecting all processes not supported");
2268   if (pid == LLDB_INVALID_PROCESS_ID)
2269     return SendErrorResponse(llvm::make_error<StringError>(
2270         inconvertibleErrorCode(), "No current process and no PID provided"));
2271 
2272   // Check the process ID and find respective process instance.
2273   auto new_process_it = m_debugged_processes.find(pid);
2274   if (new_process_it == m_debugged_processes.end())
2275     return SendErrorResponse(llvm::make_error<StringError>(
2276         inconvertibleErrorCode(),
2277         llvm::formatv("No process with PID {0} debugged", pid)));
2278 
2279   // Ensure we have the given thread when not specifying -1 (all threads) or 0
2280   // (any thread).
2281   if (tid != LLDB_INVALID_THREAD_ID && tid != 0) {
2282     NativeThreadProtocol *thread =
2283         new_process_it->second.process_up->GetThreadByID(tid);
2284     if (!thread) {
2285       LLDB_LOGF(log,
2286                 "GDBRemoteCommunicationServerLLGS::%s failed, tid %" PRIu64
2287                 " not found",
2288                 __FUNCTION__, tid);
2289       return SendErrorResponse(0x15);
2290     }
2291   }
2292 
2293   // Now switch the given process and thread type.
2294   switch (h_variant) {
2295   case 'g':
2296     m_current_process = new_process_it->second.process_up.get();
2297     SetCurrentThreadID(tid);
2298     break;
2299 
2300   case 'c':
2301     m_continue_process = new_process_it->second.process_up.get();
2302     SetContinueThreadID(tid);
2303     break;
2304 
2305   default:
2306     assert(false && "unsupported $H variant - shouldn't get here");
2307     return SendIllFormedResponse(packet,
2308                                  "H variant unsupported, should be c or g");
2309   }
2310 
2311   return SendOKResponse();
2312 }
2313 
2314 GDBRemoteCommunication::PacketResult
2315 GDBRemoteCommunicationServerLLGS::Handle_I(StringExtractorGDBRemote &packet) {
2316   Log *log = GetLog(LLDBLog::Thread);
2317 
2318   // Fail if we don't have a current process.
2319   if (!m_current_process ||
2320       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2321     LLDB_LOGF(
2322         log,
2323         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2324         __FUNCTION__);
2325     return SendErrorResponse(0x15);
2326   }
2327 
2328   packet.SetFilePos(::strlen("I"));
2329   uint8_t tmp[4096];
2330   for (;;) {
2331     size_t read = packet.GetHexBytesAvail(tmp);
2332     if (read == 0) {
2333       break;
2334     }
2335     // write directly to stdin *this might block if stdin buffer is full*
2336     // TODO: enqueue this block in circular buffer and send window size to
2337     // remote host
2338     ConnectionStatus status;
2339     Status error;
2340     m_stdio_communication.Write(tmp, read, status, &error);
2341     if (error.Fail()) {
2342       return SendErrorResponse(0x15);
2343     }
2344   }
2345 
2346   return SendOKResponse();
2347 }
2348 
2349 GDBRemoteCommunication::PacketResult
2350 GDBRemoteCommunicationServerLLGS::Handle_interrupt(
2351     StringExtractorGDBRemote &packet) {
2352   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
2353 
2354   // Fail if we don't have a current process.
2355   if (!m_current_process ||
2356       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2357     LLDB_LOG(log, "failed, no process available");
2358     return SendErrorResponse(0x15);
2359   }
2360 
2361   // Interrupt the process.
2362   Status error = m_current_process->Interrupt();
2363   if (error.Fail()) {
2364     LLDB_LOG(log, "failed for process {0}: {1}", m_current_process->GetID(),
2365              error);
2366     return SendErrorResponse(GDBRemoteServerError::eErrorResume);
2367   }
2368 
2369   LLDB_LOG(log, "stopped process {0}", m_current_process->GetID());
2370 
2371   // No response required from stop all.
2372   return PacketResult::Success;
2373 }
2374 
2375 GDBRemoteCommunication::PacketResult
2376 GDBRemoteCommunicationServerLLGS::Handle_memory_read(
2377     StringExtractorGDBRemote &packet) {
2378   Log *log = GetLog(LLDBLog::Process);
2379 
2380   if (!m_current_process ||
2381       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2382     LLDB_LOGF(
2383         log,
2384         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2385         __FUNCTION__);
2386     return SendErrorResponse(0x15);
2387   }
2388 
2389   // Parse out the memory address.
2390   packet.SetFilePos(strlen("m"));
2391   if (packet.GetBytesLeft() < 1)
2392     return SendIllFormedResponse(packet, "Too short m packet");
2393 
2394   // Read the address.  Punting on validation.
2395   // FIXME replace with Hex U64 read with no default value that fails on failed
2396   // read.
2397   const lldb::addr_t read_addr = packet.GetHexMaxU64(false, 0);
2398 
2399   // Validate comma.
2400   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != ','))
2401     return SendIllFormedResponse(packet, "Comma sep missing in m packet");
2402 
2403   // Get # bytes to read.
2404   if (packet.GetBytesLeft() < 1)
2405     return SendIllFormedResponse(packet, "Length missing in m packet");
2406 
2407   const uint64_t byte_count = packet.GetHexMaxU64(false, 0);
2408   if (byte_count == 0) {
2409     LLDB_LOGF(log,
2410               "GDBRemoteCommunicationServerLLGS::%s nothing to read: "
2411               "zero-length packet",
2412               __FUNCTION__);
2413     return SendOKResponse();
2414   }
2415 
2416   // Allocate the response buffer.
2417   std::string buf(byte_count, '\0');
2418   if (buf.empty())
2419     return SendErrorResponse(0x78);
2420 
2421   // Retrieve the process memory.
2422   size_t bytes_read = 0;
2423   Status error = m_current_process->ReadMemoryWithoutTrap(
2424       read_addr, &buf[0], byte_count, bytes_read);
2425   if (error.Fail()) {
2426     LLDB_LOGF(log,
2427               "GDBRemoteCommunicationServerLLGS::%s pid %" PRIu64
2428               " mem 0x%" PRIx64 ": failed to read. Error: %s",
2429               __FUNCTION__, m_current_process->GetID(), read_addr,
2430               error.AsCString());
2431     return SendErrorResponse(0x08);
2432   }
2433 
2434   if (bytes_read == 0) {
2435     LLDB_LOGF(log,
2436               "GDBRemoteCommunicationServerLLGS::%s pid %" PRIu64
2437               " mem 0x%" PRIx64 ": read 0 of %" PRIu64 " requested bytes",
2438               __FUNCTION__, m_current_process->GetID(), read_addr, byte_count);
2439     return SendErrorResponse(0x08);
2440   }
2441 
2442   StreamGDBRemote response;
2443   packet.SetFilePos(0);
2444   char kind = packet.GetChar('?');
2445   if (kind == 'x')
2446     response.PutEscapedBytes(buf.data(), byte_count);
2447   else {
2448     assert(kind == 'm');
2449     for (size_t i = 0; i < bytes_read; ++i)
2450       response.PutHex8(buf[i]);
2451   }
2452 
2453   return SendPacketNoLock(response.GetString());
2454 }
2455 
2456 GDBRemoteCommunication::PacketResult
2457 GDBRemoteCommunicationServerLLGS::Handle__M(StringExtractorGDBRemote &packet) {
2458   Log *log = GetLog(LLDBLog::Process);
2459 
2460   if (!m_current_process ||
2461       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2462     LLDB_LOGF(
2463         log,
2464         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2465         __FUNCTION__);
2466     return SendErrorResponse(0x15);
2467   }
2468 
2469   // Parse out the memory address.
2470   packet.SetFilePos(strlen("_M"));
2471   if (packet.GetBytesLeft() < 1)
2472     return SendIllFormedResponse(packet, "Too short _M packet");
2473 
2474   const lldb::addr_t size = packet.GetHexMaxU64(false, LLDB_INVALID_ADDRESS);
2475   if (size == LLDB_INVALID_ADDRESS)
2476     return SendIllFormedResponse(packet, "Address not valid");
2477   if (packet.GetChar() != ',')
2478     return SendIllFormedResponse(packet, "Bad packet");
2479   Permissions perms = {};
2480   while (packet.GetBytesLeft() > 0) {
2481     switch (packet.GetChar()) {
2482     case 'r':
2483       perms |= ePermissionsReadable;
2484       break;
2485     case 'w':
2486       perms |= ePermissionsWritable;
2487       break;
2488     case 'x':
2489       perms |= ePermissionsExecutable;
2490       break;
2491     default:
2492       return SendIllFormedResponse(packet, "Bad permissions");
2493     }
2494   }
2495 
2496   llvm::Expected<addr_t> addr = m_current_process->AllocateMemory(size, perms);
2497   if (!addr)
2498     return SendErrorResponse(addr.takeError());
2499 
2500   StreamGDBRemote response;
2501   response.PutHex64(*addr);
2502   return SendPacketNoLock(response.GetString());
2503 }
2504 
2505 GDBRemoteCommunication::PacketResult
2506 GDBRemoteCommunicationServerLLGS::Handle__m(StringExtractorGDBRemote &packet) {
2507   Log *log = GetLog(LLDBLog::Process);
2508 
2509   if (!m_current_process ||
2510       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2511     LLDB_LOGF(
2512         log,
2513         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2514         __FUNCTION__);
2515     return SendErrorResponse(0x15);
2516   }
2517 
2518   // Parse out the memory address.
2519   packet.SetFilePos(strlen("_m"));
2520   if (packet.GetBytesLeft() < 1)
2521     return SendIllFormedResponse(packet, "Too short m packet");
2522 
2523   const lldb::addr_t addr = packet.GetHexMaxU64(false, LLDB_INVALID_ADDRESS);
2524   if (addr == LLDB_INVALID_ADDRESS)
2525     return SendIllFormedResponse(packet, "Address not valid");
2526 
2527   if (llvm::Error Err = m_current_process->DeallocateMemory(addr))
2528     return SendErrorResponse(std::move(Err));
2529 
2530   return SendOKResponse();
2531 }
2532 
2533 GDBRemoteCommunication::PacketResult
2534 GDBRemoteCommunicationServerLLGS::Handle_M(StringExtractorGDBRemote &packet) {
2535   Log *log = GetLog(LLDBLog::Process);
2536 
2537   if (!m_current_process ||
2538       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2539     LLDB_LOGF(
2540         log,
2541         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2542         __FUNCTION__);
2543     return SendErrorResponse(0x15);
2544   }
2545 
2546   // Parse out the memory address.
2547   packet.SetFilePos(strlen("M"));
2548   if (packet.GetBytesLeft() < 1)
2549     return SendIllFormedResponse(packet, "Too short M packet");
2550 
2551   // Read the address.  Punting on validation.
2552   // FIXME replace with Hex U64 read with no default value that fails on failed
2553   // read.
2554   const lldb::addr_t write_addr = packet.GetHexMaxU64(false, 0);
2555 
2556   // Validate comma.
2557   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != ','))
2558     return SendIllFormedResponse(packet, "Comma sep missing in M packet");
2559 
2560   // Get # bytes to read.
2561   if (packet.GetBytesLeft() < 1)
2562     return SendIllFormedResponse(packet, "Length missing in M packet");
2563 
2564   const uint64_t byte_count = packet.GetHexMaxU64(false, 0);
2565   if (byte_count == 0) {
2566     LLDB_LOG(log, "nothing to write: zero-length packet");
2567     return PacketResult::Success;
2568   }
2569 
2570   // Validate colon.
2571   if ((packet.GetBytesLeft() < 1) || (packet.GetChar() != ':'))
2572     return SendIllFormedResponse(
2573         packet, "Comma sep missing in M packet after byte length");
2574 
2575   // Allocate the conversion buffer.
2576   std::vector<uint8_t> buf(byte_count, 0);
2577   if (buf.empty())
2578     return SendErrorResponse(0x78);
2579 
2580   // Convert the hex memory write contents to bytes.
2581   StreamGDBRemote response;
2582   const uint64_t convert_count = packet.GetHexBytes(buf, 0);
2583   if (convert_count != byte_count) {
2584     LLDB_LOG(log,
2585              "pid {0} mem {1:x}: asked to write {2} bytes, but only found {3} "
2586              "to convert.",
2587              m_current_process->GetID(), write_addr, byte_count, convert_count);
2588     return SendIllFormedResponse(packet, "M content byte length specified did "
2589                                          "not match hex-encoded content "
2590                                          "length");
2591   }
2592 
2593   // Write the process memory.
2594   size_t bytes_written = 0;
2595   Status error = m_current_process->WriteMemory(write_addr, &buf[0], byte_count,
2596                                                 bytes_written);
2597   if (error.Fail()) {
2598     LLDB_LOG(log, "pid {0} mem {1:x}: failed to write. Error: {2}",
2599              m_current_process->GetID(), write_addr, error);
2600     return SendErrorResponse(0x09);
2601   }
2602 
2603   if (bytes_written == 0) {
2604     LLDB_LOG(log, "pid {0} mem {1:x}: wrote 0 of {2} requested bytes",
2605              m_current_process->GetID(), write_addr, byte_count);
2606     return SendErrorResponse(0x09);
2607   }
2608 
2609   return SendOKResponse();
2610 }
2611 
2612 GDBRemoteCommunication::PacketResult
2613 GDBRemoteCommunicationServerLLGS::Handle_qMemoryRegionInfoSupported(
2614     StringExtractorGDBRemote &packet) {
2615   Log *log = GetLog(LLDBLog::Process);
2616 
2617   // Currently only the NativeProcessProtocol knows if it can handle a
2618   // qMemoryRegionInfoSupported request, but we're not guaranteed to be
2619   // attached to a process.  For now we'll assume the client only asks this
2620   // when a process is being debugged.
2621 
2622   // Ensure we have a process running; otherwise, we can't figure this out
2623   // since we won't have a NativeProcessProtocol.
2624   if (!m_current_process ||
2625       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2626     LLDB_LOGF(
2627         log,
2628         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2629         __FUNCTION__);
2630     return SendErrorResponse(0x15);
2631   }
2632 
2633   // Test if we can get any region back when asking for the region around NULL.
2634   MemoryRegionInfo region_info;
2635   const Status error = m_current_process->GetMemoryRegionInfo(0, region_info);
2636   if (error.Fail()) {
2637     // We don't support memory region info collection for this
2638     // NativeProcessProtocol.
2639     return SendUnimplementedResponse("");
2640   }
2641 
2642   return SendOKResponse();
2643 }
2644 
2645 GDBRemoteCommunication::PacketResult
2646 GDBRemoteCommunicationServerLLGS::Handle_qMemoryRegionInfo(
2647     StringExtractorGDBRemote &packet) {
2648   Log *log = GetLog(LLDBLog::Process);
2649 
2650   // Ensure we have a process.
2651   if (!m_current_process ||
2652       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2653     LLDB_LOGF(
2654         log,
2655         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2656         __FUNCTION__);
2657     return SendErrorResponse(0x15);
2658   }
2659 
2660   // Parse out the memory address.
2661   packet.SetFilePos(strlen("qMemoryRegionInfo:"));
2662   if (packet.GetBytesLeft() < 1)
2663     return SendIllFormedResponse(packet, "Too short qMemoryRegionInfo: packet");
2664 
2665   // Read the address.  Punting on validation.
2666   const lldb::addr_t read_addr = packet.GetHexMaxU64(false, 0);
2667 
2668   StreamGDBRemote response;
2669 
2670   // Get the memory region info for the target address.
2671   MemoryRegionInfo region_info;
2672   const Status error =
2673       m_current_process->GetMemoryRegionInfo(read_addr, region_info);
2674   if (error.Fail()) {
2675     // Return the error message.
2676 
2677     response.PutCString("error:");
2678     response.PutStringAsRawHex8(error.AsCString());
2679     response.PutChar(';');
2680   } else {
2681     // Range start and size.
2682     response.Printf("start:%" PRIx64 ";size:%" PRIx64 ";",
2683                     region_info.GetRange().GetRangeBase(),
2684                     region_info.GetRange().GetByteSize());
2685 
2686     // Permissions.
2687     if (region_info.GetReadable() || region_info.GetWritable() ||
2688         region_info.GetExecutable()) {
2689       // Write permissions info.
2690       response.PutCString("permissions:");
2691 
2692       if (region_info.GetReadable())
2693         response.PutChar('r');
2694       if (region_info.GetWritable())
2695         response.PutChar('w');
2696       if (region_info.GetExecutable())
2697         response.PutChar('x');
2698 
2699       response.PutChar(';');
2700     }
2701 
2702     // Flags
2703     MemoryRegionInfo::OptionalBool memory_tagged =
2704         region_info.GetMemoryTagged();
2705     if (memory_tagged != MemoryRegionInfo::eDontKnow) {
2706       response.PutCString("flags:");
2707       if (memory_tagged == MemoryRegionInfo::eYes) {
2708         response.PutCString("mt");
2709       }
2710       response.PutChar(';');
2711     }
2712 
2713     // Name
2714     ConstString name = region_info.GetName();
2715     if (name) {
2716       response.PutCString("name:");
2717       response.PutStringAsRawHex8(name.GetStringRef());
2718       response.PutChar(';');
2719     }
2720   }
2721 
2722   return SendPacketNoLock(response.GetString());
2723 }
2724 
2725 GDBRemoteCommunication::PacketResult
2726 GDBRemoteCommunicationServerLLGS::Handle_Z(StringExtractorGDBRemote &packet) {
2727   // Ensure we have a process.
2728   if (!m_current_process ||
2729       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2730     Log *log = GetLog(LLDBLog::Process);
2731     LLDB_LOG(log, "failed, no process available");
2732     return SendErrorResponse(0x15);
2733   }
2734 
2735   // Parse out software or hardware breakpoint or watchpoint requested.
2736   packet.SetFilePos(strlen("Z"));
2737   if (packet.GetBytesLeft() < 1)
2738     return SendIllFormedResponse(
2739         packet, "Too short Z packet, missing software/hardware specifier");
2740 
2741   bool want_breakpoint = true;
2742   bool want_hardware = false;
2743   uint32_t watch_flags = 0;
2744 
2745   const GDBStoppointType stoppoint_type =
2746       GDBStoppointType(packet.GetS32(eStoppointInvalid));
2747   switch (stoppoint_type) {
2748   case eBreakpointSoftware:
2749     want_hardware = false;
2750     want_breakpoint = true;
2751     break;
2752   case eBreakpointHardware:
2753     want_hardware = true;
2754     want_breakpoint = true;
2755     break;
2756   case eWatchpointWrite:
2757     watch_flags = 1;
2758     want_hardware = true;
2759     want_breakpoint = false;
2760     break;
2761   case eWatchpointRead:
2762     watch_flags = 2;
2763     want_hardware = true;
2764     want_breakpoint = false;
2765     break;
2766   case eWatchpointReadWrite:
2767     watch_flags = 3;
2768     want_hardware = true;
2769     want_breakpoint = false;
2770     break;
2771   case eStoppointInvalid:
2772     return SendIllFormedResponse(
2773         packet, "Z packet had invalid software/hardware specifier");
2774   }
2775 
2776   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2777     return SendIllFormedResponse(
2778         packet, "Malformed Z packet, expecting comma after stoppoint type");
2779 
2780   // Parse out the stoppoint address.
2781   if (packet.GetBytesLeft() < 1)
2782     return SendIllFormedResponse(packet, "Too short Z packet, missing address");
2783   const lldb::addr_t addr = packet.GetHexMaxU64(false, 0);
2784 
2785   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2786     return SendIllFormedResponse(
2787         packet, "Malformed Z packet, expecting comma after address");
2788 
2789   // Parse out the stoppoint size (i.e. size hint for opcode size).
2790   const uint32_t size =
2791       packet.GetHexMaxU32(false, std::numeric_limits<uint32_t>::max());
2792   if (size == std::numeric_limits<uint32_t>::max())
2793     return SendIllFormedResponse(
2794         packet, "Malformed Z packet, failed to parse size argument");
2795 
2796   if (want_breakpoint) {
2797     // Try to set the breakpoint.
2798     const Status error =
2799         m_current_process->SetBreakpoint(addr, size, want_hardware);
2800     if (error.Success())
2801       return SendOKResponse();
2802     Log *log = GetLog(LLDBLog::Breakpoints);
2803     LLDB_LOG(log, "pid {0} failed to set breakpoint: {1}",
2804              m_current_process->GetID(), error);
2805     return SendErrorResponse(0x09);
2806   } else {
2807     // Try to set the watchpoint.
2808     const Status error = m_current_process->SetWatchpoint(
2809         addr, size, watch_flags, want_hardware);
2810     if (error.Success())
2811       return SendOKResponse();
2812     Log *log = GetLog(LLDBLog::Watchpoints);
2813     LLDB_LOG(log, "pid {0} failed to set watchpoint: {1}",
2814              m_current_process->GetID(), error);
2815     return SendErrorResponse(0x09);
2816   }
2817 }
2818 
2819 GDBRemoteCommunication::PacketResult
2820 GDBRemoteCommunicationServerLLGS::Handle_z(StringExtractorGDBRemote &packet) {
2821   // Ensure we have a process.
2822   if (!m_current_process ||
2823       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2824     Log *log = GetLog(LLDBLog::Process);
2825     LLDB_LOG(log, "failed, no process available");
2826     return SendErrorResponse(0x15);
2827   }
2828 
2829   // Parse out software or hardware breakpoint or watchpoint requested.
2830   packet.SetFilePos(strlen("z"));
2831   if (packet.GetBytesLeft() < 1)
2832     return SendIllFormedResponse(
2833         packet, "Too short z packet, missing software/hardware specifier");
2834 
2835   bool want_breakpoint = true;
2836   bool want_hardware = false;
2837 
2838   const GDBStoppointType stoppoint_type =
2839       GDBStoppointType(packet.GetS32(eStoppointInvalid));
2840   switch (stoppoint_type) {
2841   case eBreakpointHardware:
2842     want_breakpoint = true;
2843     want_hardware = true;
2844     break;
2845   case eBreakpointSoftware:
2846     want_breakpoint = true;
2847     break;
2848   case eWatchpointWrite:
2849     want_breakpoint = false;
2850     break;
2851   case eWatchpointRead:
2852     want_breakpoint = false;
2853     break;
2854   case eWatchpointReadWrite:
2855     want_breakpoint = false;
2856     break;
2857   default:
2858     return SendIllFormedResponse(
2859         packet, "z packet had invalid software/hardware specifier");
2860   }
2861 
2862   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2863     return SendIllFormedResponse(
2864         packet, "Malformed z packet, expecting comma after stoppoint type");
2865 
2866   // Parse out the stoppoint address.
2867   if (packet.GetBytesLeft() < 1)
2868     return SendIllFormedResponse(packet, "Too short z packet, missing address");
2869   const lldb::addr_t addr = packet.GetHexMaxU64(false, 0);
2870 
2871   if ((packet.GetBytesLeft() < 1) || packet.GetChar() != ',')
2872     return SendIllFormedResponse(
2873         packet, "Malformed z packet, expecting comma after address");
2874 
2875   /*
2876   // Parse out the stoppoint size (i.e. size hint for opcode size).
2877   const uint32_t size = packet.GetHexMaxU32 (false,
2878   std::numeric_limits<uint32_t>::max ());
2879   if (size == std::numeric_limits<uint32_t>::max ())
2880       return SendIllFormedResponse(packet, "Malformed z packet, failed to parse
2881   size argument");
2882   */
2883 
2884   if (want_breakpoint) {
2885     // Try to clear the breakpoint.
2886     const Status error =
2887         m_current_process->RemoveBreakpoint(addr, want_hardware);
2888     if (error.Success())
2889       return SendOKResponse();
2890     Log *log = GetLog(LLDBLog::Breakpoints);
2891     LLDB_LOG(log, "pid {0} failed to remove breakpoint: {1}",
2892              m_current_process->GetID(), error);
2893     return SendErrorResponse(0x09);
2894   } else {
2895     // Try to clear the watchpoint.
2896     const Status error = m_current_process->RemoveWatchpoint(addr);
2897     if (error.Success())
2898       return SendOKResponse();
2899     Log *log = GetLog(LLDBLog::Watchpoints);
2900     LLDB_LOG(log, "pid {0} failed to remove watchpoint: {1}",
2901              m_current_process->GetID(), error);
2902     return SendErrorResponse(0x09);
2903   }
2904 }
2905 
2906 GDBRemoteCommunication::PacketResult
2907 GDBRemoteCommunicationServerLLGS::Handle_s(StringExtractorGDBRemote &packet) {
2908   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
2909 
2910   // Ensure we have a process.
2911   if (!m_continue_process ||
2912       (m_continue_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
2913     LLDB_LOGF(
2914         log,
2915         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
2916         __FUNCTION__);
2917     return SendErrorResponse(0x32);
2918   }
2919 
2920   // We first try to use a continue thread id.  If any one or any all set, use
2921   // the current thread. Bail out if we don't have a thread id.
2922   lldb::tid_t tid = GetContinueThreadID();
2923   if (tid == 0 || tid == LLDB_INVALID_THREAD_ID)
2924     tid = GetCurrentThreadID();
2925   if (tid == LLDB_INVALID_THREAD_ID)
2926     return SendErrorResponse(0x33);
2927 
2928   // Double check that we have such a thread.
2929   // TODO investigate: on MacOSX we might need to do an UpdateThreads () here.
2930   NativeThreadProtocol *thread = m_continue_process->GetThreadByID(tid);
2931   if (!thread)
2932     return SendErrorResponse(0x33);
2933 
2934   // Create the step action for the given thread.
2935   ResumeAction action = {tid, eStateStepping, LLDB_INVALID_SIGNAL_NUMBER};
2936 
2937   // Setup the actions list.
2938   ResumeActionList actions;
2939   actions.Append(action);
2940 
2941   // All other threads stop while we're single stepping a thread.
2942   actions.SetDefaultThreadActionIfNeeded(eStateStopped, 0);
2943   Status error = m_continue_process->Resume(actions);
2944   if (error.Fail()) {
2945     LLDB_LOGF(log,
2946               "GDBRemoteCommunicationServerLLGS::%s pid %" PRIu64
2947               " tid %" PRIu64 " Resume() failed with error: %s",
2948               __FUNCTION__, m_continue_process->GetID(), tid,
2949               error.AsCString());
2950     return SendErrorResponse(0x49);
2951   }
2952 
2953   // No response here, unless in non-stop mode.
2954   // Otherwise, the stop or exit will come from the resulting action.
2955   return SendContinueSuccessResponse();
2956 }
2957 
2958 llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>>
2959 GDBRemoteCommunicationServerLLGS::BuildTargetXml() {
2960   // Ensure we have a thread.
2961   NativeThreadProtocol *thread = m_current_process->GetThreadAtIndex(0);
2962   if (!thread)
2963     return llvm::createStringError(llvm::inconvertibleErrorCode(),
2964                                    "No thread available");
2965 
2966   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
2967   // Get the register context for the first thread.
2968   NativeRegisterContext &reg_context = thread->GetRegisterContext();
2969 
2970   StreamString response;
2971 
2972   response.Printf("<?xml version=\"1.0\"?>");
2973   response.Printf("<target version=\"1.0\">");
2974 
2975   response.Printf("<architecture>%s</architecture>",
2976                   m_current_process->GetArchitecture()
2977                       .GetTriple()
2978                       .getArchName()
2979                       .str()
2980                       .c_str());
2981 
2982   response.Printf("<feature>");
2983 
2984   const int registers_count = reg_context.GetUserRegisterCount();
2985   for (int reg_index = 0; reg_index < registers_count; reg_index++) {
2986     const RegisterInfo *reg_info =
2987         reg_context.GetRegisterInfoAtIndex(reg_index);
2988 
2989     if (!reg_info) {
2990       LLDB_LOGF(log,
2991                 "%s failed to get register info for register index %" PRIu32,
2992                 "target.xml", reg_index);
2993       continue;
2994     }
2995 
2996     response.Printf("<reg name=\"%s\" bitsize=\"%" PRIu32 "\" regnum=\"%d\" ",
2997                     reg_info->name, reg_info->byte_size * 8, reg_index);
2998 
2999     if (!reg_context.RegisterOffsetIsDynamic())
3000       response.Printf("offset=\"%" PRIu32 "\" ", reg_info->byte_offset);
3001 
3002     if (reg_info->alt_name && reg_info->alt_name[0])
3003       response.Printf("altname=\"%s\" ", reg_info->alt_name);
3004 
3005     llvm::StringRef encoding = GetEncodingNameOrEmpty(*reg_info);
3006     if (!encoding.empty())
3007       response << "encoding=\"" << encoding << "\" ";
3008 
3009     llvm::StringRef format = GetFormatNameOrEmpty(*reg_info);
3010     if (!format.empty())
3011       response << "format=\"" << format << "\" ";
3012 
3013     const char *const register_set_name =
3014         reg_context.GetRegisterSetNameForRegisterAtIndex(reg_index);
3015     if (register_set_name)
3016       response << "group=\"" << register_set_name << "\" ";
3017 
3018     if (reg_info->kinds[RegisterKind::eRegisterKindEHFrame] !=
3019         LLDB_INVALID_REGNUM)
3020       response.Printf("ehframe_regnum=\"%" PRIu32 "\" ",
3021                       reg_info->kinds[RegisterKind::eRegisterKindEHFrame]);
3022 
3023     if (reg_info->kinds[RegisterKind::eRegisterKindDWARF] !=
3024         LLDB_INVALID_REGNUM)
3025       response.Printf("dwarf_regnum=\"%" PRIu32 "\" ",
3026                       reg_info->kinds[RegisterKind::eRegisterKindDWARF]);
3027 
3028     llvm::StringRef kind_generic = GetKindGenericOrEmpty(*reg_info);
3029     if (!kind_generic.empty())
3030       response << "generic=\"" << kind_generic << "\" ";
3031 
3032     if (reg_info->value_regs &&
3033         reg_info->value_regs[0] != LLDB_INVALID_REGNUM) {
3034       response.PutCString("value_regnums=\"");
3035       CollectRegNums(reg_info->value_regs, response, false);
3036       response.Printf("\" ");
3037     }
3038 
3039     if (reg_info->invalidate_regs && reg_info->invalidate_regs[0]) {
3040       response.PutCString("invalidate_regnums=\"");
3041       CollectRegNums(reg_info->invalidate_regs, response, false);
3042       response.Printf("\" ");
3043     }
3044 
3045     response.Printf("/>");
3046   }
3047 
3048   response.Printf("</feature>");
3049   response.Printf("</target>");
3050   return MemoryBuffer::getMemBufferCopy(response.GetString(), "target.xml");
3051 }
3052 
3053 llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>>
3054 GDBRemoteCommunicationServerLLGS::ReadXferObject(llvm::StringRef object,
3055                                                  llvm::StringRef annex) {
3056   // Make sure we have a valid process.
3057   if (!m_current_process ||
3058       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
3059     return llvm::createStringError(llvm::inconvertibleErrorCode(),
3060                                    "No process available");
3061   }
3062 
3063   if (object == "auxv") {
3064     // Grab the auxv data.
3065     auto buffer_or_error = m_current_process->GetAuxvData();
3066     if (!buffer_or_error)
3067       return llvm::errorCodeToError(buffer_or_error.getError());
3068     return std::move(*buffer_or_error);
3069   }
3070 
3071   if (object == "siginfo") {
3072     NativeThreadProtocol *thread = m_current_process->GetCurrentThread();
3073     if (!thread)
3074       return llvm::createStringError(llvm::inconvertibleErrorCode(),
3075                                      "no current thread");
3076 
3077     auto buffer_or_error = thread->GetSiginfo();
3078     if (!buffer_or_error)
3079       return buffer_or_error.takeError();
3080     return std::move(*buffer_or_error);
3081   }
3082 
3083   if (object == "libraries-svr4") {
3084     auto library_list = m_current_process->GetLoadedSVR4Libraries();
3085     if (!library_list)
3086       return library_list.takeError();
3087 
3088     StreamString response;
3089     response.Printf("<library-list-svr4 version=\"1.0\">");
3090     for (auto const &library : *library_list) {
3091       response.Printf("<library name=\"%s\" ",
3092                       XMLEncodeAttributeValue(library.name.c_str()).c_str());
3093       response.Printf("lm=\"0x%" PRIx64 "\" ", library.link_map);
3094       response.Printf("l_addr=\"0x%" PRIx64 "\" ", library.base_addr);
3095       response.Printf("l_ld=\"0x%" PRIx64 "\" />", library.ld_addr);
3096     }
3097     response.Printf("</library-list-svr4>");
3098     return MemoryBuffer::getMemBufferCopy(response.GetString(), __FUNCTION__);
3099   }
3100 
3101   if (object == "features" && annex == "target.xml")
3102     return BuildTargetXml();
3103 
3104   return llvm::make_error<UnimplementedError>();
3105 }
3106 
3107 GDBRemoteCommunication::PacketResult
3108 GDBRemoteCommunicationServerLLGS::Handle_qXfer(
3109     StringExtractorGDBRemote &packet) {
3110   SmallVector<StringRef, 5> fields;
3111   // The packet format is "qXfer:<object>:<action>:<annex>:offset,length"
3112   StringRef(packet.GetStringRef()).split(fields, ':', 4);
3113   if (fields.size() != 5)
3114     return SendIllFormedResponse(packet, "malformed qXfer packet");
3115   StringRef &xfer_object = fields[1];
3116   StringRef &xfer_action = fields[2];
3117   StringRef &xfer_annex = fields[3];
3118   StringExtractor offset_data(fields[4]);
3119   if (xfer_action != "read")
3120     return SendUnimplementedResponse("qXfer action not supported");
3121   // Parse offset.
3122   const uint64_t xfer_offset =
3123       offset_data.GetHexMaxU64(false, std::numeric_limits<uint64_t>::max());
3124   if (xfer_offset == std::numeric_limits<uint64_t>::max())
3125     return SendIllFormedResponse(packet, "qXfer packet missing offset");
3126   // Parse out comma.
3127   if (offset_data.GetChar() != ',')
3128     return SendIllFormedResponse(packet,
3129                                  "qXfer packet missing comma after offset");
3130   // Parse out the length.
3131   const uint64_t xfer_length =
3132       offset_data.GetHexMaxU64(false, std::numeric_limits<uint64_t>::max());
3133   if (xfer_length == std::numeric_limits<uint64_t>::max())
3134     return SendIllFormedResponse(packet, "qXfer packet missing length");
3135 
3136   // Get a previously constructed buffer if it exists or create it now.
3137   std::string buffer_key = (xfer_object + xfer_action + xfer_annex).str();
3138   auto buffer_it = m_xfer_buffer_map.find(buffer_key);
3139   if (buffer_it == m_xfer_buffer_map.end()) {
3140     auto buffer_up = ReadXferObject(xfer_object, xfer_annex);
3141     if (!buffer_up)
3142       return SendErrorResponse(buffer_up.takeError());
3143     buffer_it = m_xfer_buffer_map
3144                     .insert(std::make_pair(buffer_key, std::move(*buffer_up)))
3145                     .first;
3146   }
3147 
3148   // Send back the response
3149   StreamGDBRemote response;
3150   bool done_with_buffer = false;
3151   llvm::StringRef buffer = buffer_it->second->getBuffer();
3152   if (xfer_offset >= buffer.size()) {
3153     // We have nothing left to send.  Mark the buffer as complete.
3154     response.PutChar('l');
3155     done_with_buffer = true;
3156   } else {
3157     // Figure out how many bytes are available starting at the given offset.
3158     buffer = buffer.drop_front(xfer_offset);
3159     // Mark the response type according to whether we're reading the remainder
3160     // of the data.
3161     if (xfer_length >= buffer.size()) {
3162       // There will be nothing left to read after this
3163       response.PutChar('l');
3164       done_with_buffer = true;
3165     } else {
3166       // There will still be bytes to read after this request.
3167       response.PutChar('m');
3168       buffer = buffer.take_front(xfer_length);
3169     }
3170     // Now write the data in encoded binary form.
3171     response.PutEscapedBytes(buffer.data(), buffer.size());
3172   }
3173 
3174   if (done_with_buffer)
3175     m_xfer_buffer_map.erase(buffer_it);
3176 
3177   return SendPacketNoLock(response.GetString());
3178 }
3179 
3180 GDBRemoteCommunication::PacketResult
3181 GDBRemoteCommunicationServerLLGS::Handle_QSaveRegisterState(
3182     StringExtractorGDBRemote &packet) {
3183   Log *log = GetLog(LLDBLog::Thread);
3184 
3185   // Move past packet name.
3186   packet.SetFilePos(strlen("QSaveRegisterState"));
3187 
3188   // Get the thread to use.
3189   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
3190   if (!thread) {
3191     if (m_thread_suffix_supported)
3192       return SendIllFormedResponse(
3193           packet, "No thread specified in QSaveRegisterState packet");
3194     else
3195       return SendIllFormedResponse(packet,
3196                                    "No thread was is set with the Hg packet");
3197   }
3198 
3199   // Grab the register context for the thread.
3200   NativeRegisterContext& reg_context = thread->GetRegisterContext();
3201 
3202   // Save registers to a buffer.
3203   WritableDataBufferSP register_data_sp;
3204   Status error = reg_context.ReadAllRegisterValues(register_data_sp);
3205   if (error.Fail()) {
3206     LLDB_LOG(log, "pid {0} failed to save all register values: {1}",
3207              m_current_process->GetID(), error);
3208     return SendErrorResponse(0x75);
3209   }
3210 
3211   // Allocate a new save id.
3212   const uint32_t save_id = GetNextSavedRegistersID();
3213   assert((m_saved_registers_map.find(save_id) == m_saved_registers_map.end()) &&
3214          "GetNextRegisterSaveID() returned an existing register save id");
3215 
3216   // Save the register data buffer under the save id.
3217   {
3218     std::lock_guard<std::mutex> guard(m_saved_registers_mutex);
3219     m_saved_registers_map[save_id] = register_data_sp;
3220   }
3221 
3222   // Write the response.
3223   StreamGDBRemote response;
3224   response.Printf("%" PRIu32, save_id);
3225   return SendPacketNoLock(response.GetString());
3226 }
3227 
3228 GDBRemoteCommunication::PacketResult
3229 GDBRemoteCommunicationServerLLGS::Handle_QRestoreRegisterState(
3230     StringExtractorGDBRemote &packet) {
3231   Log *log = GetLog(LLDBLog::Thread);
3232 
3233   // Parse out save id.
3234   packet.SetFilePos(strlen("QRestoreRegisterState:"));
3235   if (packet.GetBytesLeft() < 1)
3236     return SendIllFormedResponse(
3237         packet, "QRestoreRegisterState packet missing register save id");
3238 
3239   const uint32_t save_id = packet.GetU32(0);
3240   if (save_id == 0) {
3241     LLDB_LOG(log, "QRestoreRegisterState packet has malformed save id, "
3242                   "expecting decimal uint32_t");
3243     return SendErrorResponse(0x76);
3244   }
3245 
3246   // Get the thread to use.
3247   NativeThreadProtocol *thread = GetThreadFromSuffix(packet);
3248   if (!thread) {
3249     if (m_thread_suffix_supported)
3250       return SendIllFormedResponse(
3251           packet, "No thread specified in QRestoreRegisterState packet");
3252     else
3253       return SendIllFormedResponse(packet,
3254                                    "No thread was is set with the Hg packet");
3255   }
3256 
3257   // Grab the register context for the thread.
3258   NativeRegisterContext &reg_context = thread->GetRegisterContext();
3259 
3260   // Retrieve register state buffer, then remove from the list.
3261   DataBufferSP register_data_sp;
3262   {
3263     std::lock_guard<std::mutex> guard(m_saved_registers_mutex);
3264 
3265     // Find the register set buffer for the given save id.
3266     auto it = m_saved_registers_map.find(save_id);
3267     if (it == m_saved_registers_map.end()) {
3268       LLDB_LOG(log,
3269                "pid {0} does not have a register set save buffer for id {1}",
3270                m_current_process->GetID(), save_id);
3271       return SendErrorResponse(0x77);
3272     }
3273     register_data_sp = it->second;
3274 
3275     // Remove it from the map.
3276     m_saved_registers_map.erase(it);
3277   }
3278 
3279   Status error = reg_context.WriteAllRegisterValues(register_data_sp);
3280   if (error.Fail()) {
3281     LLDB_LOG(log, "pid {0} failed to restore all register values: {1}",
3282              m_current_process->GetID(), error);
3283     return SendErrorResponse(0x77);
3284   }
3285 
3286   return SendOKResponse();
3287 }
3288 
3289 GDBRemoteCommunication::PacketResult
3290 GDBRemoteCommunicationServerLLGS::Handle_vAttach(
3291     StringExtractorGDBRemote &packet) {
3292   Log *log = GetLog(LLDBLog::Process);
3293 
3294   // Consume the ';' after vAttach.
3295   packet.SetFilePos(strlen("vAttach"));
3296   if (!packet.GetBytesLeft() || packet.GetChar() != ';')
3297     return SendIllFormedResponse(packet, "vAttach missing expected ';'");
3298 
3299   // Grab the PID to which we will attach (assume hex encoding).
3300   lldb::pid_t pid = packet.GetU32(LLDB_INVALID_PROCESS_ID, 16);
3301   if (pid == LLDB_INVALID_PROCESS_ID)
3302     return SendIllFormedResponse(packet,
3303                                  "vAttach failed to parse the process id");
3304 
3305   // Attempt to attach.
3306   LLDB_LOGF(log,
3307             "GDBRemoteCommunicationServerLLGS::%s attempting to attach to "
3308             "pid %" PRIu64,
3309             __FUNCTION__, pid);
3310 
3311   Status error = AttachToProcess(pid);
3312 
3313   if (error.Fail()) {
3314     LLDB_LOGF(log,
3315               "GDBRemoteCommunicationServerLLGS::%s failed to attach to "
3316               "pid %" PRIu64 ": %s\n",
3317               __FUNCTION__, pid, error.AsCString());
3318     return SendErrorResponse(error);
3319   }
3320 
3321   // Notify we attached by sending a stop packet.
3322   assert(m_current_process);
3323   return SendStopReasonForState(*m_current_process,
3324                                 m_current_process->GetState(),
3325                                 /*force_synchronous=*/false);
3326 }
3327 
3328 GDBRemoteCommunication::PacketResult
3329 GDBRemoteCommunicationServerLLGS::Handle_vAttachWait(
3330     StringExtractorGDBRemote &packet) {
3331   Log *log = GetLog(LLDBLog::Process);
3332 
3333   // Consume the ';' after the identifier.
3334   packet.SetFilePos(strlen("vAttachWait"));
3335 
3336   if (!packet.GetBytesLeft() || packet.GetChar() != ';')
3337     return SendIllFormedResponse(packet, "vAttachWait missing expected ';'");
3338 
3339   // Allocate the buffer for the process name from vAttachWait.
3340   std::string process_name;
3341   if (!packet.GetHexByteString(process_name))
3342     return SendIllFormedResponse(packet,
3343                                  "vAttachWait failed to parse process name");
3344 
3345   LLDB_LOG(log, "attempting to attach to process named '{0}'", process_name);
3346 
3347   Status error = AttachWaitProcess(process_name, false);
3348   if (error.Fail()) {
3349     LLDB_LOG(log, "failed to attach to process named '{0}': {1}", process_name,
3350              error);
3351     return SendErrorResponse(error);
3352   }
3353 
3354   // Notify we attached by sending a stop packet.
3355   assert(m_current_process);
3356   return SendStopReasonForState(*m_current_process,
3357                                 m_current_process->GetState(),
3358                                 /*force_synchronous=*/false);
3359 }
3360 
3361 GDBRemoteCommunication::PacketResult
3362 GDBRemoteCommunicationServerLLGS::Handle_qVAttachOrWaitSupported(
3363     StringExtractorGDBRemote &packet) {
3364   return SendOKResponse();
3365 }
3366 
3367 GDBRemoteCommunication::PacketResult
3368 GDBRemoteCommunicationServerLLGS::Handle_vAttachOrWait(
3369     StringExtractorGDBRemote &packet) {
3370   Log *log = GetLog(LLDBLog::Process);
3371 
3372   // Consume the ';' after the identifier.
3373   packet.SetFilePos(strlen("vAttachOrWait"));
3374 
3375   if (!packet.GetBytesLeft() || packet.GetChar() != ';')
3376     return SendIllFormedResponse(packet, "vAttachOrWait missing expected ';'");
3377 
3378   // Allocate the buffer for the process name from vAttachWait.
3379   std::string process_name;
3380   if (!packet.GetHexByteString(process_name))
3381     return SendIllFormedResponse(packet,
3382                                  "vAttachOrWait failed to parse process name");
3383 
3384   LLDB_LOG(log, "attempting to attach to process named '{0}'", process_name);
3385 
3386   Status error = AttachWaitProcess(process_name, true);
3387   if (error.Fail()) {
3388     LLDB_LOG(log, "failed to attach to process named '{0}': {1}", process_name,
3389              error);
3390     return SendErrorResponse(error);
3391   }
3392 
3393   // Notify we attached by sending a stop packet.
3394   assert(m_current_process);
3395   return SendStopReasonForState(*m_current_process,
3396                                 m_current_process->GetState(),
3397                                 /*force_synchronous=*/false);
3398 }
3399 
3400 GDBRemoteCommunication::PacketResult
3401 GDBRemoteCommunicationServerLLGS::Handle_vRun(
3402     StringExtractorGDBRemote &packet) {
3403   Log *log = GetLog(LLDBLog::Process);
3404 
3405   llvm::StringRef s = packet.GetStringRef();
3406   if (!s.consume_front("vRun;"))
3407     return SendErrorResponse(8);
3408 
3409   llvm::SmallVector<llvm::StringRef, 16> argv;
3410   s.split(argv, ';');
3411 
3412   for (llvm::StringRef hex_arg : argv) {
3413     StringExtractor arg_ext{hex_arg};
3414     std::string arg;
3415     arg_ext.GetHexByteString(arg);
3416     m_process_launch_info.GetArguments().AppendArgument(arg);
3417     LLDB_LOGF(log, "LLGSPacketHandler::%s added arg: \"%s\"", __FUNCTION__,
3418               arg.c_str());
3419   }
3420 
3421   if (!argv.empty()) {
3422     m_process_launch_info.GetExecutableFile().SetFile(
3423         m_process_launch_info.GetArguments()[0].ref(), FileSpec::Style::native);
3424     m_process_launch_error = LaunchProcess();
3425     if (m_process_launch_error.Success()) {
3426       assert(m_current_process);
3427       return SendStopReasonForState(*m_current_process,
3428                                     m_current_process->GetState(),
3429                                     /*force_synchronous=*/true);
3430     }
3431     LLDB_LOG(log, "failed to launch exe: {0}", m_process_launch_error);
3432   }
3433   return SendErrorResponse(8);
3434 }
3435 
3436 GDBRemoteCommunication::PacketResult
3437 GDBRemoteCommunicationServerLLGS::Handle_D(StringExtractorGDBRemote &packet) {
3438   Log *log = GetLog(LLDBLog::Process);
3439   StopSTDIOForwarding();
3440 
3441   lldb::pid_t pid = LLDB_INVALID_PROCESS_ID;
3442 
3443   // Consume the ';' after D.
3444   packet.SetFilePos(1);
3445   if (packet.GetBytesLeft()) {
3446     if (packet.GetChar() != ';')
3447       return SendIllFormedResponse(packet, "D missing expected ';'");
3448 
3449     // Grab the PID from which we will detach (assume hex encoding).
3450     pid = packet.GetU32(LLDB_INVALID_PROCESS_ID, 16);
3451     if (pid == LLDB_INVALID_PROCESS_ID)
3452       return SendIllFormedResponse(packet, "D failed to parse the process id");
3453   }
3454 
3455   // Detach forked children if their PID was specified *or* no PID was requested
3456   // (i.e. detach-all packet).
3457   llvm::Error detach_error = llvm::Error::success();
3458   bool detached = false;
3459   for (auto it = m_debugged_processes.begin();
3460        it != m_debugged_processes.end();) {
3461     if (pid == LLDB_INVALID_PROCESS_ID || pid == it->first) {
3462       LLDB_LOGF(log,
3463                 "GDBRemoteCommunicationServerLLGS::%s detaching %" PRId64,
3464                 __FUNCTION__, it->first);
3465       if (llvm::Error e = it->second.process_up->Detach().ToError())
3466         detach_error = llvm::joinErrors(std::move(detach_error), std::move(e));
3467       else {
3468         if (it->second.process_up.get() == m_current_process)
3469           m_current_process = nullptr;
3470         if (it->second.process_up.get() == m_continue_process)
3471           m_continue_process = nullptr;
3472         it = m_debugged_processes.erase(it);
3473         detached = true;
3474         continue;
3475       }
3476     }
3477     ++it;
3478   }
3479 
3480   if (detach_error)
3481     return SendErrorResponse(std::move(detach_error));
3482   if (!detached)
3483     return SendErrorResponse(Status("PID %" PRIu64 " not traced", pid));
3484   return SendOKResponse();
3485 }
3486 
3487 GDBRemoteCommunication::PacketResult
3488 GDBRemoteCommunicationServerLLGS::Handle_qThreadStopInfo(
3489     StringExtractorGDBRemote &packet) {
3490   Log *log = GetLog(LLDBLog::Thread);
3491 
3492   if (!m_current_process ||
3493       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
3494     return SendErrorResponse(50);
3495 
3496   packet.SetFilePos(strlen("qThreadStopInfo"));
3497   const lldb::tid_t tid = packet.GetHexMaxU64(false, LLDB_INVALID_THREAD_ID);
3498   if (tid == LLDB_INVALID_THREAD_ID) {
3499     LLDB_LOGF(log,
3500               "GDBRemoteCommunicationServerLLGS::%s failed, could not "
3501               "parse thread id from request \"%s\"",
3502               __FUNCTION__, packet.GetStringRef().data());
3503     return SendErrorResponse(0x15);
3504   }
3505   return SendStopReplyPacketForThread(*m_current_process, tid,
3506                                       /*force_synchronous=*/true);
3507 }
3508 
3509 GDBRemoteCommunication::PacketResult
3510 GDBRemoteCommunicationServerLLGS::Handle_jThreadsInfo(
3511     StringExtractorGDBRemote &) {
3512   Log *log = GetLog(LLDBLog::Process | LLDBLog::Thread);
3513 
3514   // Ensure we have a debugged process.
3515   if (!m_current_process ||
3516       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
3517     return SendErrorResponse(50);
3518   LLDB_LOG(log, "preparing packet for pid {0}", m_current_process->GetID());
3519 
3520   StreamString response;
3521   const bool threads_with_valid_stop_info_only = false;
3522   llvm::Expected<json::Value> threads_info =
3523       GetJSONThreadsInfo(*m_current_process, threads_with_valid_stop_info_only);
3524   if (!threads_info) {
3525     LLDB_LOG_ERROR(log, threads_info.takeError(),
3526                    "failed to prepare a packet for pid {1}: {0}",
3527                    m_current_process->GetID());
3528     return SendErrorResponse(52);
3529   }
3530 
3531   response.AsRawOstream() << *threads_info;
3532   StreamGDBRemote escaped_response;
3533   escaped_response.PutEscapedBytes(response.GetData(), response.GetSize());
3534   return SendPacketNoLock(escaped_response.GetString());
3535 }
3536 
3537 GDBRemoteCommunication::PacketResult
3538 GDBRemoteCommunicationServerLLGS::Handle_qWatchpointSupportInfo(
3539     StringExtractorGDBRemote &packet) {
3540   // Fail if we don't have a current process.
3541   if (!m_current_process ||
3542       m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)
3543     return SendErrorResponse(68);
3544 
3545   packet.SetFilePos(strlen("qWatchpointSupportInfo"));
3546   if (packet.GetBytesLeft() == 0)
3547     return SendOKResponse();
3548   if (packet.GetChar() != ':')
3549     return SendErrorResponse(67);
3550 
3551   auto hw_debug_cap = m_current_process->GetHardwareDebugSupportInfo();
3552 
3553   StreamGDBRemote response;
3554   if (hw_debug_cap == llvm::None)
3555     response.Printf("num:0;");
3556   else
3557     response.Printf("num:%d;", hw_debug_cap->second);
3558 
3559   return SendPacketNoLock(response.GetString());
3560 }
3561 
3562 GDBRemoteCommunication::PacketResult
3563 GDBRemoteCommunicationServerLLGS::Handle_qFileLoadAddress(
3564     StringExtractorGDBRemote &packet) {
3565   // Fail if we don't have a current process.
3566   if (!m_current_process ||
3567       m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)
3568     return SendErrorResponse(67);
3569 
3570   packet.SetFilePos(strlen("qFileLoadAddress:"));
3571   if (packet.GetBytesLeft() == 0)
3572     return SendErrorResponse(68);
3573 
3574   std::string file_name;
3575   packet.GetHexByteString(file_name);
3576 
3577   lldb::addr_t file_load_address = LLDB_INVALID_ADDRESS;
3578   Status error =
3579       m_current_process->GetFileLoadAddress(file_name, file_load_address);
3580   if (error.Fail())
3581     return SendErrorResponse(69);
3582 
3583   if (file_load_address == LLDB_INVALID_ADDRESS)
3584     return SendErrorResponse(1); // File not loaded
3585 
3586   StreamGDBRemote response;
3587   response.PutHex64(file_load_address);
3588   return SendPacketNoLock(response.GetString());
3589 }
3590 
3591 GDBRemoteCommunication::PacketResult
3592 GDBRemoteCommunicationServerLLGS::Handle_QPassSignals(
3593     StringExtractorGDBRemote &packet) {
3594   std::vector<int> signals;
3595   packet.SetFilePos(strlen("QPassSignals:"));
3596 
3597   // Read sequence of hex signal numbers divided by a semicolon and optionally
3598   // spaces.
3599   while (packet.GetBytesLeft() > 0) {
3600     int signal = packet.GetS32(-1, 16);
3601     if (signal < 0)
3602       return SendIllFormedResponse(packet, "Failed to parse signal number.");
3603     signals.push_back(signal);
3604 
3605     packet.SkipSpaces();
3606     char separator = packet.GetChar();
3607     if (separator == '\0')
3608       break; // End of string
3609     if (separator != ';')
3610       return SendIllFormedResponse(packet, "Invalid separator,"
3611                                             " expected semicolon.");
3612   }
3613 
3614   // Fail if we don't have a current process.
3615   if (!m_current_process)
3616     return SendErrorResponse(68);
3617 
3618   Status error = m_current_process->IgnoreSignals(signals);
3619   if (error.Fail())
3620     return SendErrorResponse(69);
3621 
3622   return SendOKResponse();
3623 }
3624 
3625 GDBRemoteCommunication::PacketResult
3626 GDBRemoteCommunicationServerLLGS::Handle_qMemTags(
3627     StringExtractorGDBRemote &packet) {
3628   Log *log = GetLog(LLDBLog::Process);
3629 
3630   // Ensure we have a process.
3631   if (!m_current_process ||
3632       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
3633     LLDB_LOGF(
3634         log,
3635         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
3636         __FUNCTION__);
3637     return SendErrorResponse(1);
3638   }
3639 
3640   // We are expecting
3641   // qMemTags:<hex address>,<hex length>:<hex type>
3642 
3643   // Address
3644   packet.SetFilePos(strlen("qMemTags:"));
3645   const char *current_char = packet.Peek();
3646   if (!current_char || *current_char == ',')
3647     return SendIllFormedResponse(packet, "Missing address in qMemTags packet");
3648   const lldb::addr_t addr = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3649 
3650   // Length
3651   char previous_char = packet.GetChar();
3652   current_char = packet.Peek();
3653   // If we don't have a separator or the length field is empty
3654   if (previous_char != ',' || (current_char && *current_char == ':'))
3655     return SendIllFormedResponse(packet,
3656                                  "Invalid addr,length pair in qMemTags packet");
3657 
3658   if (packet.GetBytesLeft() < 1)
3659     return SendIllFormedResponse(
3660         packet, "Too short qMemtags: packet (looking for length)");
3661   const size_t length = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3662 
3663   // Type
3664   const char *invalid_type_err = "Invalid type field in qMemTags: packet";
3665   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ':')
3666     return SendIllFormedResponse(packet, invalid_type_err);
3667 
3668   // Type is a signed integer but packed into the packet as its raw bytes.
3669   // However, our GetU64 uses strtoull which allows +/-. We do not want this.
3670   const char *first_type_char = packet.Peek();
3671   if (first_type_char && (*first_type_char == '+' || *first_type_char == '-'))
3672     return SendIllFormedResponse(packet, invalid_type_err);
3673 
3674   // Extract type as unsigned then cast to signed.
3675   // Using a uint64_t here so that we have some value outside of the 32 bit
3676   // range to use as the invalid return value.
3677   uint64_t raw_type =
3678       packet.GetU64(std::numeric_limits<uint64_t>::max(), /*base=*/16);
3679 
3680   if ( // Make sure the cast below would be valid
3681       raw_type > std::numeric_limits<uint32_t>::max() ||
3682       // To catch inputs like "123aardvark" that will parse but clearly aren't
3683       // valid in this case.
3684       packet.GetBytesLeft()) {
3685     return SendIllFormedResponse(packet, invalid_type_err);
3686   }
3687 
3688   // First narrow to 32 bits otherwise the copy into type would take
3689   // the wrong 4 bytes on big endian.
3690   uint32_t raw_type_32 = raw_type;
3691   int32_t type = reinterpret_cast<int32_t &>(raw_type_32);
3692 
3693   StreamGDBRemote response;
3694   std::vector<uint8_t> tags;
3695   Status error = m_current_process->ReadMemoryTags(type, addr, length, tags);
3696   if (error.Fail())
3697     return SendErrorResponse(1);
3698 
3699   // This m is here in case we want to support multi part replies in the future.
3700   // In the same manner as qfThreadInfo/qsThreadInfo.
3701   response.PutChar('m');
3702   response.PutBytesAsRawHex8(tags.data(), tags.size());
3703   return SendPacketNoLock(response.GetString());
3704 }
3705 
3706 GDBRemoteCommunication::PacketResult
3707 GDBRemoteCommunicationServerLLGS::Handle_QMemTags(
3708     StringExtractorGDBRemote &packet) {
3709   Log *log = GetLog(LLDBLog::Process);
3710 
3711   // Ensure we have a process.
3712   if (!m_current_process ||
3713       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)) {
3714     LLDB_LOGF(
3715         log,
3716         "GDBRemoteCommunicationServerLLGS::%s failed, no process available",
3717         __FUNCTION__);
3718     return SendErrorResponse(1);
3719   }
3720 
3721   // We are expecting
3722   // QMemTags:<hex address>,<hex length>:<hex type>:<tags as hex bytes>
3723 
3724   // Address
3725   packet.SetFilePos(strlen("QMemTags:"));
3726   const char *current_char = packet.Peek();
3727   if (!current_char || *current_char == ',')
3728     return SendIllFormedResponse(packet, "Missing address in QMemTags packet");
3729   const lldb::addr_t addr = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3730 
3731   // Length
3732   char previous_char = packet.GetChar();
3733   current_char = packet.Peek();
3734   // If we don't have a separator or the length field is empty
3735   if (previous_char != ',' || (current_char && *current_char == ':'))
3736     return SendIllFormedResponse(packet,
3737                                  "Invalid addr,length pair in QMemTags packet");
3738 
3739   if (packet.GetBytesLeft() < 1)
3740     return SendIllFormedResponse(
3741         packet, "Too short QMemtags: packet (looking for length)");
3742   const size_t length = packet.GetHexMaxU64(/*little_endian=*/false, 0);
3743 
3744   // Type
3745   const char *invalid_type_err = "Invalid type field in QMemTags: packet";
3746   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ':')
3747     return SendIllFormedResponse(packet, invalid_type_err);
3748 
3749   // Our GetU64 uses strtoull which allows leading +/-, we don't want that.
3750   const char *first_type_char = packet.Peek();
3751   if (first_type_char && (*first_type_char == '+' || *first_type_char == '-'))
3752     return SendIllFormedResponse(packet, invalid_type_err);
3753 
3754   // The type is a signed integer but is in the packet as its raw bytes.
3755   // So parse first as unsigned then cast to signed later.
3756   // We extract to 64 bit, even though we only expect 32, so that we've
3757   // got some invalid value we can check for.
3758   uint64_t raw_type =
3759       packet.GetU64(std::numeric_limits<uint64_t>::max(), /*base=*/16);
3760   if (raw_type > std::numeric_limits<uint32_t>::max())
3761     return SendIllFormedResponse(packet, invalid_type_err);
3762 
3763   // First narrow to 32 bits. Otherwise the copy below would get the wrong
3764   // 4 bytes on big endian.
3765   uint32_t raw_type_32 = raw_type;
3766   int32_t type = reinterpret_cast<int32_t &>(raw_type_32);
3767 
3768   // Tag data
3769   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ':')
3770     return SendIllFormedResponse(packet,
3771                                  "Missing tag data in QMemTags: packet");
3772 
3773   // Must be 2 chars per byte
3774   const char *invalid_data_err = "Invalid tag data in QMemTags: packet";
3775   if (packet.GetBytesLeft() % 2)
3776     return SendIllFormedResponse(packet, invalid_data_err);
3777 
3778   // This is bytes here and is unpacked into target specific tags later
3779   // We cannot assume that number of bytes == length here because the server
3780   // can repeat tags to fill a given range.
3781   std::vector<uint8_t> tag_data;
3782   // Zero length writes will not have any tag data
3783   // (but we pass them on because it will still check that tagging is enabled)
3784   if (packet.GetBytesLeft()) {
3785     size_t byte_count = packet.GetBytesLeft() / 2;
3786     tag_data.resize(byte_count);
3787     size_t converted_bytes = packet.GetHexBytes(tag_data, 0);
3788     if (converted_bytes != byte_count) {
3789       return SendIllFormedResponse(packet, invalid_data_err);
3790     }
3791   }
3792 
3793   Status status =
3794       m_current_process->WriteMemoryTags(type, addr, length, tag_data);
3795   return status.Success() ? SendOKResponse() : SendErrorResponse(1);
3796 }
3797 
3798 GDBRemoteCommunication::PacketResult
3799 GDBRemoteCommunicationServerLLGS::Handle_qSaveCore(
3800     StringExtractorGDBRemote &packet) {
3801   // Fail if we don't have a current process.
3802   if (!m_current_process ||
3803       (m_current_process->GetID() == LLDB_INVALID_PROCESS_ID))
3804     return SendErrorResponse(Status("Process not running."));
3805 
3806   std::string path_hint;
3807 
3808   StringRef packet_str{packet.GetStringRef()};
3809   assert(packet_str.startswith("qSaveCore"));
3810   if (packet_str.consume_front("qSaveCore;")) {
3811     for (auto x : llvm::split(packet_str, ';')) {
3812       if (x.consume_front("path-hint:"))
3813         StringExtractor(x).GetHexByteString(path_hint);
3814       else
3815         return SendErrorResponse(Status("Unsupported qSaveCore option"));
3816     }
3817   }
3818 
3819   llvm::Expected<std::string> ret = m_current_process->SaveCore(path_hint);
3820   if (!ret)
3821     return SendErrorResponse(ret.takeError());
3822 
3823   StreamString response;
3824   response.PutCString("core-path:");
3825   response.PutStringAsRawHex8(ret.get());
3826   return SendPacketNoLock(response.GetString());
3827 }
3828 
3829 GDBRemoteCommunication::PacketResult
3830 GDBRemoteCommunicationServerLLGS::Handle_QNonStop(
3831     StringExtractorGDBRemote &packet) {
3832   StringRef packet_str{packet.GetStringRef()};
3833   assert(packet_str.startswith("QNonStop:"));
3834   packet_str.consume_front("QNonStop:");
3835   if (packet_str == "0") {
3836     m_non_stop = false;
3837     // TODO: stop all threads
3838   } else if (packet_str == "1") {
3839     m_non_stop = true;
3840   } else
3841     return SendErrorResponse(Status("Invalid QNonStop packet"));
3842   return SendOKResponse();
3843 }
3844 
3845 GDBRemoteCommunication::PacketResult
3846 GDBRemoteCommunicationServerLLGS::Handle_vStopped(
3847     StringExtractorGDBRemote &packet) {
3848   // Per the protocol, the first message put into the queue is sent
3849   // immediately.  However, it remains the queue until the client ACKs
3850   // it via vStopped -- then we pop it and send the next message.
3851   // The process repeats until the last message in the queue is ACK-ed,
3852   // in which case the vStopped packet sends an OK response.
3853 
3854   if (m_stop_notification_queue.empty())
3855     return SendErrorResponse(Status("No pending notification to ack"));
3856   m_stop_notification_queue.pop_front();
3857   if (!m_stop_notification_queue.empty())
3858     return SendPacketNoLock(m_stop_notification_queue.front());
3859   // If this was the last notification and all the processes exited,
3860   // terminate the server.
3861   if (m_debugged_processes.empty()) {
3862     m_exit_now = true;
3863     m_mainloop.RequestTermination();
3864   }
3865   return SendOKResponse();
3866 }
3867 
3868 GDBRemoteCommunication::PacketResult
3869 GDBRemoteCommunicationServerLLGS::Handle_vCtrlC(
3870     StringExtractorGDBRemote &packet) {
3871   if (!m_non_stop)
3872     return SendErrorResponse(Status("vCtrl is only valid in non-stop mode"));
3873 
3874   PacketResult interrupt_res = Handle_interrupt(packet);
3875   // If interrupting the process failed, pass the result through.
3876   if (interrupt_res != PacketResult::Success)
3877     return interrupt_res;
3878   // Otherwise, vCtrlC should issue an OK response (normal interrupts do not).
3879   return SendOKResponse();
3880 }
3881 
3882 GDBRemoteCommunication::PacketResult
3883 GDBRemoteCommunicationServerLLGS::Handle_T(StringExtractorGDBRemote &packet) {
3884   packet.SetFilePos(strlen("T"));
3885   auto pid_tid = packet.GetPidTid(m_current_process ? m_current_process->GetID()
3886                                                     : LLDB_INVALID_PROCESS_ID);
3887   if (!pid_tid)
3888     return SendErrorResponse(llvm::make_error<StringError>(
3889         inconvertibleErrorCode(), "Malformed thread-id"));
3890 
3891   lldb::pid_t pid = pid_tid->first;
3892   lldb::tid_t tid = pid_tid->second;
3893 
3894   // Technically, this would also be caught by the PID check but let's be more
3895   // explicit about the error.
3896   if (pid == LLDB_INVALID_PROCESS_ID)
3897     return SendErrorResponse(llvm::make_error<StringError>(
3898         inconvertibleErrorCode(), "No current process and no PID provided"));
3899 
3900   // Check the process ID and find respective process instance.
3901   auto new_process_it = m_debugged_processes.find(pid);
3902   if (new_process_it == m_debugged_processes.end())
3903     return SendErrorResponse(1);
3904 
3905   // Check the thread ID
3906   if (!new_process_it->second.process_up->GetThreadByID(tid))
3907     return SendErrorResponse(2);
3908 
3909   return SendOKResponse();
3910 }
3911 
3912 void GDBRemoteCommunicationServerLLGS::MaybeCloseInferiorTerminalConnection() {
3913   Log *log = GetLog(LLDBLog::Process);
3914 
3915   // Tell the stdio connection to shut down.
3916   if (m_stdio_communication.IsConnected()) {
3917     auto connection = m_stdio_communication.GetConnection();
3918     if (connection) {
3919       Status error;
3920       connection->Disconnect(&error);
3921 
3922       if (error.Success()) {
3923         LLDB_LOGF(log,
3924                   "GDBRemoteCommunicationServerLLGS::%s disconnect process "
3925                   "terminal stdio - SUCCESS",
3926                   __FUNCTION__);
3927       } else {
3928         LLDB_LOGF(log,
3929                   "GDBRemoteCommunicationServerLLGS::%s disconnect process "
3930                   "terminal stdio - FAIL: %s",
3931                   __FUNCTION__, error.AsCString());
3932       }
3933     }
3934   }
3935 }
3936 
3937 NativeThreadProtocol *GDBRemoteCommunicationServerLLGS::GetThreadFromSuffix(
3938     StringExtractorGDBRemote &packet) {
3939   // We have no thread if we don't have a process.
3940   if (!m_current_process ||
3941       m_current_process->GetID() == LLDB_INVALID_PROCESS_ID)
3942     return nullptr;
3943 
3944   // If the client hasn't asked for thread suffix support, there will not be a
3945   // thread suffix. Use the current thread in that case.
3946   if (!m_thread_suffix_supported) {
3947     const lldb::tid_t current_tid = GetCurrentThreadID();
3948     if (current_tid == LLDB_INVALID_THREAD_ID)
3949       return nullptr;
3950     else if (current_tid == 0) {
3951       // Pick a thread.
3952       return m_current_process->GetThreadAtIndex(0);
3953     } else
3954       return m_current_process->GetThreadByID(current_tid);
3955   }
3956 
3957   Log *log = GetLog(LLDBLog::Thread);
3958 
3959   // Parse out the ';'.
3960   if (packet.GetBytesLeft() < 1 || packet.GetChar() != ';') {
3961     LLDB_LOGF(log,
3962               "GDBRemoteCommunicationServerLLGS::%s gdb-remote parse "
3963               "error: expected ';' prior to start of thread suffix: packet "
3964               "contents = '%s'",
3965               __FUNCTION__, packet.GetStringRef().data());
3966     return nullptr;
3967   }
3968 
3969   if (!packet.GetBytesLeft())
3970     return nullptr;
3971 
3972   // Parse out thread: portion.
3973   if (strncmp(packet.Peek(), "thread:", strlen("thread:")) != 0) {
3974     LLDB_LOGF(log,
3975               "GDBRemoteCommunicationServerLLGS::%s gdb-remote parse "
3976               "error: expected 'thread:' but not found, packet contents = "
3977               "'%s'",
3978               __FUNCTION__, packet.GetStringRef().data());
3979     return nullptr;
3980   }
3981   packet.SetFilePos(packet.GetFilePos() + strlen("thread:"));
3982   const lldb::tid_t tid = packet.GetHexMaxU64(false, 0);
3983   if (tid != 0)
3984     return m_current_process->GetThreadByID(tid);
3985 
3986   return nullptr;
3987 }
3988 
3989 lldb::tid_t GDBRemoteCommunicationServerLLGS::GetCurrentThreadID() const {
3990   if (m_current_tid == 0 || m_current_tid == LLDB_INVALID_THREAD_ID) {
3991     // Use whatever the debug process says is the current thread id since the
3992     // protocol either didn't specify or specified we want any/all threads
3993     // marked as the current thread.
3994     if (!m_current_process)
3995       return LLDB_INVALID_THREAD_ID;
3996     return m_current_process->GetCurrentThreadID();
3997   }
3998   // Use the specific current thread id set by the gdb remote protocol.
3999   return m_current_tid;
4000 }
4001 
4002 uint32_t GDBRemoteCommunicationServerLLGS::GetNextSavedRegistersID() {
4003   std::lock_guard<std::mutex> guard(m_saved_registers_mutex);
4004   return m_next_saved_registers_id++;
4005 }
4006 
4007 void GDBRemoteCommunicationServerLLGS::ClearProcessSpecificData() {
4008   Log *log = GetLog(LLDBLog::Process);
4009 
4010   LLDB_LOG(log, "clearing {0} xfer buffers", m_xfer_buffer_map.size());
4011   m_xfer_buffer_map.clear();
4012 }
4013 
4014 FileSpec
4015 GDBRemoteCommunicationServerLLGS::FindModuleFile(const std::string &module_path,
4016                                                  const ArchSpec &arch) {
4017   if (m_current_process) {
4018     FileSpec file_spec;
4019     if (m_current_process
4020             ->GetLoadedModuleFileSpec(module_path.c_str(), file_spec)
4021             .Success()) {
4022       if (FileSystem::Instance().Exists(file_spec))
4023         return file_spec;
4024     }
4025   }
4026 
4027   return GDBRemoteCommunicationServerCommon::FindModuleFile(module_path, arch);
4028 }
4029 
4030 std::string GDBRemoteCommunicationServerLLGS::XMLEncodeAttributeValue(
4031     llvm::StringRef value) {
4032   std::string result;
4033   for (const char &c : value) {
4034     switch (c) {
4035     case '\'':
4036       result += "&apos;";
4037       break;
4038     case '"':
4039       result += "&quot;";
4040       break;
4041     case '<':
4042       result += "&lt;";
4043       break;
4044     case '>':
4045       result += "&gt;";
4046       break;
4047     default:
4048       result += c;
4049       break;
4050     }
4051   }
4052   return result;
4053 }
4054 
4055 std::vector<std::string> GDBRemoteCommunicationServerLLGS::HandleFeatures(
4056     const llvm::ArrayRef<llvm::StringRef> client_features) {
4057   std::vector<std::string> ret =
4058       GDBRemoteCommunicationServerCommon::HandleFeatures(client_features);
4059   ret.insert(ret.end(), {
4060                             "QThreadSuffixSupported+",
4061                             "QListThreadsInStopReply+",
4062                             "qXfer:features:read+",
4063                             "QNonStop+",
4064                         });
4065 
4066   // report server-only features
4067   using Extension = NativeProcessProtocol::Extension;
4068   Extension plugin_features = m_process_factory.GetSupportedExtensions();
4069   if (bool(plugin_features & Extension::pass_signals))
4070     ret.push_back("QPassSignals+");
4071   if (bool(plugin_features & Extension::auxv))
4072     ret.push_back("qXfer:auxv:read+");
4073   if (bool(plugin_features & Extension::libraries_svr4))
4074     ret.push_back("qXfer:libraries-svr4:read+");
4075   if (bool(plugin_features & Extension::siginfo_read))
4076     ret.push_back("qXfer:siginfo:read+");
4077   if (bool(plugin_features & Extension::memory_tagging))
4078     ret.push_back("memory-tagging+");
4079   if (bool(plugin_features & Extension::savecore))
4080     ret.push_back("qSaveCore+");
4081 
4082   // check for client features
4083   m_extensions_supported = {};
4084   for (llvm::StringRef x : client_features)
4085     m_extensions_supported |=
4086         llvm::StringSwitch<Extension>(x)
4087             .Case("multiprocess+", Extension::multiprocess)
4088             .Case("fork-events+", Extension::fork)
4089             .Case("vfork-events+", Extension::vfork)
4090             .Default({});
4091 
4092   m_extensions_supported &= plugin_features;
4093 
4094   // fork & vfork require multiprocess
4095   if (!bool(m_extensions_supported & Extension::multiprocess))
4096     m_extensions_supported &= ~(Extension::fork | Extension::vfork);
4097 
4098   // report only if actually supported
4099   if (bool(m_extensions_supported & Extension::multiprocess))
4100     ret.push_back("multiprocess+");
4101   if (bool(m_extensions_supported & Extension::fork))
4102     ret.push_back("fork-events+");
4103   if (bool(m_extensions_supported & Extension::vfork))
4104     ret.push_back("vfork-events+");
4105 
4106   for (auto &x : m_debugged_processes)
4107     SetEnabledExtensions(*x.second.process_up);
4108   return ret;
4109 }
4110 
4111 void GDBRemoteCommunicationServerLLGS::SetEnabledExtensions(
4112     NativeProcessProtocol &process) {
4113   NativeProcessProtocol::Extension flags = m_extensions_supported;
4114   assert(!bool(flags & ~m_process_factory.GetSupportedExtensions()));
4115   process.SetEnabledExtensions(flags);
4116 }
4117 
4118 GDBRemoteCommunication::PacketResult
4119 GDBRemoteCommunicationServerLLGS::SendContinueSuccessResponse() {
4120   // TODO: how to handle forwarding in non-stop mode?
4121   StartSTDIOForwarding();
4122   return m_non_stop ? SendOKResponse() : PacketResult::Success;
4123 }
4124 
4125 void GDBRemoteCommunicationServerLLGS::AppendThreadIDToResponse(
4126     Stream &response, lldb::pid_t pid, lldb::tid_t tid) {
4127   if (bool(m_extensions_supported &
4128            NativeProcessProtocol::Extension::multiprocess))
4129     response.Format("p{0:x-}.", pid);
4130   response.Format("{0:x-}", tid);
4131 }
4132 
4133 std::string
4134 lldb_private::process_gdb_remote::LLGSArgToURL(llvm::StringRef url_arg,
4135                                                bool reverse_connect) {
4136   // Try parsing the argument as URL.
4137   if (llvm::Optional<URI> url = URI::Parse(url_arg)) {
4138     if (reverse_connect)
4139       return url_arg.str();
4140 
4141     // Translate the scheme from LLGS notation to ConnectionFileDescriptor.
4142     // If the scheme doesn't match any, pass it through to support using CFD
4143     // schemes directly.
4144     std::string new_url = llvm::StringSwitch<std::string>(url->scheme)
4145                               .Case("tcp", "listen")
4146                               .Case("unix", "unix-accept")
4147                               .Case("unix-abstract", "unix-abstract-accept")
4148                               .Default(url->scheme.str());
4149     llvm::append_range(new_url, url_arg.substr(url->scheme.size()));
4150     return new_url;
4151   }
4152 
4153   std::string host_port = url_arg.str();
4154   // If host_and_port starts with ':', default the host to be "localhost" and
4155   // expect the remainder to be the port.
4156   if (url_arg.startswith(":"))
4157     host_port.insert(0, "localhost");
4158 
4159   // Try parsing the (preprocessed) argument as host:port pair.
4160   if (!llvm::errorToBool(Socket::DecodeHostAndPort(host_port).takeError()))
4161     return (reverse_connect ? "connect://" : "listen://") + host_port;
4162 
4163   // If none of the above applied, interpret the argument as UNIX socket path.
4164   return (reverse_connect ? "unix-connect://" : "unix-accept://") +
4165          url_arg.str();
4166 }
4167