1 //===-- PlatformRemoteGDBServer.cpp -----------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "PlatformRemoteGDBServer.h"
10 #include "lldb/Host/Config.h"
11 
12 #include "lldb/Breakpoint/BreakpointLocation.h"
13 #include "lldb/Core/Debugger.h"
14 #include "lldb/Core/Module.h"
15 #include "lldb/Core/ModuleList.h"
16 #include "lldb/Core/ModuleSpec.h"
17 #include "lldb/Core/PluginManager.h"
18 #include "lldb/Core/StreamFile.h"
19 #include "lldb/Host/ConnectionFileDescriptor.h"
20 #include "lldb/Host/Host.h"
21 #include "lldb/Host/HostInfo.h"
22 #include "lldb/Host/PosixApi.h"
23 #include "lldb/Target/Process.h"
24 #include "lldb/Target/Target.h"
25 #include "lldb/Utility/FileSpec.h"
26 #include "lldb/Utility/Log.h"
27 #include "lldb/Utility/ProcessInfo.h"
28 #include "lldb/Utility/Status.h"
29 #include "lldb/Utility/StreamString.h"
30 #include "lldb/Utility/UriParser.h"
31 
32 #include "Plugins/Process/Utility/GDBRemoteSignals.h"
33 
34 using namespace lldb;
35 using namespace lldb_private;
36 using namespace lldb_private::platform_gdb_server;
37 
38 static bool g_initialized = false;
39 
40 void PlatformRemoteGDBServer::Initialize() {
41   Platform::Initialize();
42 
43   if (!g_initialized) {
44     g_initialized = true;
45     PluginManager::RegisterPlugin(
46         PlatformRemoteGDBServer::GetPluginNameStatic(),
47         PlatformRemoteGDBServer::GetDescriptionStatic(),
48         PlatformRemoteGDBServer::CreateInstance);
49   }
50 }
51 
52 void PlatformRemoteGDBServer::Terminate() {
53   if (g_initialized) {
54     g_initialized = false;
55     PluginManager::UnregisterPlugin(PlatformRemoteGDBServer::CreateInstance);
56   }
57 
58   Platform::Terminate();
59 }
60 
61 PlatformSP PlatformRemoteGDBServer::CreateInstance(bool force,
62                                                    const ArchSpec *arch) {
63   bool create = force;
64   if (!create) {
65     create = !arch->TripleVendorWasSpecified() && !arch->TripleOSWasSpecified();
66   }
67   if (create)
68     return PlatformSP(new PlatformRemoteGDBServer());
69   return PlatformSP();
70 }
71 
72 ConstString PlatformRemoteGDBServer::GetPluginNameStatic() {
73   static ConstString g_name("remote-gdb-server");
74   return g_name;
75 }
76 
77 const char *PlatformRemoteGDBServer::GetDescriptionStatic() {
78   return "A platform that uses the GDB remote protocol as the communication "
79          "transport.";
80 }
81 
82 const char *PlatformRemoteGDBServer::GetDescription() {
83   if (m_platform_description.empty()) {
84     if (IsConnected()) {
85       // Send the get description packet
86     }
87   }
88 
89   if (!m_platform_description.empty())
90     return m_platform_description.c_str();
91   return GetDescriptionStatic();
92 }
93 
94 Status PlatformRemoteGDBServer::ResolveExecutable(
95     const ModuleSpec &module_spec, lldb::ModuleSP &exe_module_sp,
96     const FileSpecList *module_search_paths_ptr) {
97   // copied from PlatformRemoteiOS
98 
99   Status error;
100   // Nothing special to do here, just use the actual file and architecture
101 
102   ModuleSpec resolved_module_spec(module_spec);
103 
104   // Resolve any executable within an apk on Android?
105   // Host::ResolveExecutableInBundle (resolved_module_spec.GetFileSpec());
106 
107   if (FileSystem::Instance().Exists(resolved_module_spec.GetFileSpec()) ||
108       module_spec.GetUUID().IsValid()) {
109     if (resolved_module_spec.GetArchitecture().IsValid() ||
110         resolved_module_spec.GetUUID().IsValid()) {
111       error = ModuleList::GetSharedModule(resolved_module_spec, exe_module_sp,
112                                           module_search_paths_ptr, NULL, NULL);
113 
114       if (exe_module_sp && exe_module_sp->GetObjectFile())
115         return error;
116       exe_module_sp.reset();
117     }
118     // No valid architecture was specified or the exact arch wasn't found so
119     // ask the platform for the architectures that we should be using (in the
120     // correct order) and see if we can find a match that way
121     StreamString arch_names;
122     for (uint32_t idx = 0; GetSupportedArchitectureAtIndex(
123              idx, resolved_module_spec.GetArchitecture());
124          ++idx) {
125       error = ModuleList::GetSharedModule(resolved_module_spec, exe_module_sp,
126                                           module_search_paths_ptr, NULL, NULL);
127       // Did we find an executable using one of the
128       if (error.Success()) {
129         if (exe_module_sp && exe_module_sp->GetObjectFile())
130           break;
131         else
132           error.SetErrorToGenericError();
133       }
134 
135       if (idx > 0)
136         arch_names.PutCString(", ");
137       arch_names.PutCString(
138           resolved_module_spec.GetArchitecture().GetArchitectureName());
139     }
140 
141     if (error.Fail() || !exe_module_sp) {
142       if (FileSystem::Instance().Readable(resolved_module_spec.GetFileSpec())) {
143         error.SetErrorStringWithFormat(
144             "'%s' doesn't contain any '%s' platform architectures: %s",
145             resolved_module_spec.GetFileSpec().GetPath().c_str(),
146             GetPluginName().GetCString(), arch_names.GetData());
147       } else {
148         error.SetErrorStringWithFormat(
149             "'%s' is not readable",
150             resolved_module_spec.GetFileSpec().GetPath().c_str());
151       }
152     }
153   } else {
154     error.SetErrorStringWithFormat(
155         "'%s' does not exist",
156         resolved_module_spec.GetFileSpec().GetPath().c_str());
157   }
158 
159   return error;
160 }
161 
162 bool PlatformRemoteGDBServer::GetModuleSpec(const FileSpec &module_file_spec,
163                                             const ArchSpec &arch,
164                                             ModuleSpec &module_spec) {
165   Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
166 
167   const auto module_path = module_file_spec.GetPath(false);
168 
169   if (!m_gdb_client.GetModuleInfo(module_file_spec, arch, module_spec)) {
170     if (log)
171       log->Printf(
172           "PlatformRemoteGDBServer::%s - failed to get module info for %s:%s",
173           __FUNCTION__, module_path.c_str(),
174           arch.GetTriple().getTriple().c_str());
175     return false;
176   }
177 
178   if (log) {
179     StreamString stream;
180     module_spec.Dump(stream);
181     log->Printf(
182         "PlatformRemoteGDBServer::%s - got module info for (%s:%s) : %s",
183         __FUNCTION__, module_path.c_str(), arch.GetTriple().getTriple().c_str(),
184         stream.GetData());
185   }
186 
187   return true;
188 }
189 
190 Status PlatformRemoteGDBServer::GetFileWithUUID(const FileSpec &platform_file,
191                                                 const UUID *uuid_ptr,
192                                                 FileSpec &local_file) {
193   // Default to the local case
194   local_file = platform_file;
195   return Status();
196 }
197 
198 /// Default Constructor
199 PlatformRemoteGDBServer::PlatformRemoteGDBServer()
200     : Platform(false), // This is a remote platform
201       m_gdb_client() {}
202 
203 /// Destructor.
204 ///
205 /// The destructor is virtual since this class is designed to be
206 /// inherited from by the plug-in instance.
207 PlatformRemoteGDBServer::~PlatformRemoteGDBServer() {}
208 
209 bool PlatformRemoteGDBServer::GetSupportedArchitectureAtIndex(uint32_t idx,
210                                                               ArchSpec &arch) {
211   ArchSpec remote_arch = m_gdb_client.GetSystemArchitecture();
212 
213   if (idx == 0) {
214     arch = remote_arch;
215     return arch.IsValid();
216   } else if (idx == 1 && remote_arch.IsValid() &&
217              remote_arch.GetTriple().isArch64Bit()) {
218     arch.SetTriple(remote_arch.GetTriple().get32BitArchVariant());
219     return arch.IsValid();
220   }
221   return false;
222 }
223 
224 size_t PlatformRemoteGDBServer::GetSoftwareBreakpointTrapOpcode(
225     Target &target, BreakpointSite *bp_site) {
226   // This isn't needed if the z/Z packets are supported in the GDB remote
227   // server. But we might need a packet to detect this.
228   return 0;
229 }
230 
231 bool PlatformRemoteGDBServer::GetRemoteOSVersion() {
232   m_os_version = m_gdb_client.GetOSVersion();
233   return !m_os_version.empty();
234 }
235 
236 bool PlatformRemoteGDBServer::GetRemoteOSBuildString(std::string &s) {
237   return m_gdb_client.GetOSBuildString(s);
238 }
239 
240 bool PlatformRemoteGDBServer::GetRemoteOSKernelDescription(std::string &s) {
241   return m_gdb_client.GetOSKernelDescription(s);
242 }
243 
244 // Remote Platform subclasses need to override this function
245 ArchSpec PlatformRemoteGDBServer::GetRemoteSystemArchitecture() {
246   return m_gdb_client.GetSystemArchitecture();
247 }
248 
249 FileSpec PlatformRemoteGDBServer::GetRemoteWorkingDirectory() {
250   if (IsConnected()) {
251     Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
252     FileSpec working_dir;
253     if (m_gdb_client.GetWorkingDir(working_dir) && log)
254       log->Printf(
255           "PlatformRemoteGDBServer::GetRemoteWorkingDirectory() -> '%s'",
256           working_dir.GetCString());
257     return working_dir;
258   } else {
259     return Platform::GetRemoteWorkingDirectory();
260   }
261 }
262 
263 bool PlatformRemoteGDBServer::SetRemoteWorkingDirectory(
264     const FileSpec &working_dir) {
265   if (IsConnected()) {
266     // Clear the working directory it case it doesn't get set correctly. This
267     // will for use to re-read it
268     Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
269     if (log)
270       log->Printf("PlatformRemoteGDBServer::SetRemoteWorkingDirectory('%s')",
271                   working_dir.GetCString());
272     return m_gdb_client.SetWorkingDir(working_dir) == 0;
273   } else
274     return Platform::SetRemoteWorkingDirectory(working_dir);
275 }
276 
277 bool PlatformRemoteGDBServer::IsConnected() const {
278   return m_gdb_client.IsConnected();
279 }
280 
281 Status PlatformRemoteGDBServer::ConnectRemote(Args &args) {
282   Status error;
283   if (IsConnected()) {
284     error.SetErrorStringWithFormat("the platform is already connected to '%s', "
285                                    "execute 'platform disconnect' to close the "
286                                    "current connection",
287                                    GetHostname());
288   } else {
289     if (args.GetArgumentCount() == 1) {
290       m_gdb_client.SetConnection(new ConnectionFileDescriptor());
291       // we're going to reuse the hostname when we connect to the debugserver
292       int port;
293       std::string path;
294       const char *url = args.GetArgumentAtIndex(0);
295       if (!url)
296         return Status("URL is null.");
297       llvm::StringRef scheme, hostname, pathname;
298       if (!UriParser::Parse(url, scheme, hostname, port, pathname))
299         return Status("Invalid URL: %s", url);
300       m_platform_scheme = scheme;
301       m_platform_hostname = hostname;
302       path = pathname;
303 
304       const ConnectionStatus status = m_gdb_client.Connect(url, &error);
305       if (status == eConnectionStatusSuccess) {
306         if (m_gdb_client.HandshakeWithServer(&error)) {
307           m_gdb_client.GetHostInfo();
308           // If a working directory was set prior to connecting, send it down
309           // now
310           if (m_working_dir)
311             m_gdb_client.SetWorkingDir(m_working_dir);
312         } else {
313           m_gdb_client.Disconnect();
314           if (error.Success())
315             error.SetErrorString("handshake failed");
316         }
317       }
318     } else {
319       error.SetErrorString(
320           "\"platform connect\" takes a single argument: <connect-url>");
321     }
322   }
323   return error;
324 }
325 
326 Status PlatformRemoteGDBServer::DisconnectRemote() {
327   Status error;
328   m_gdb_client.Disconnect(&error);
329   m_remote_signals_sp.reset();
330   return error;
331 }
332 
333 const char *PlatformRemoteGDBServer::GetHostname() {
334   m_gdb_client.GetHostname(m_name);
335   if (m_name.empty())
336     return NULL;
337   return m_name.c_str();
338 }
339 
340 llvm::Optional<std::string>
341 PlatformRemoteGDBServer::DoGetUserName(UserIDResolver::id_t uid) {
342   std::string name;
343   if (m_gdb_client.GetUserName(uid, name))
344     return std::move(name);
345   return llvm::None;
346 }
347 
348 llvm::Optional<std::string>
349 PlatformRemoteGDBServer::DoGetGroupName(UserIDResolver::id_t gid) {
350   std::string name;
351   if (m_gdb_client.GetGroupName(gid, name))
352     return std::move(name);
353   return llvm::None;
354 }
355 
356 uint32_t PlatformRemoteGDBServer::FindProcesses(
357     const ProcessInstanceInfoMatch &match_info,
358     ProcessInstanceInfoList &process_infos) {
359   return m_gdb_client.FindProcesses(match_info, process_infos);
360 }
361 
362 bool PlatformRemoteGDBServer::GetProcessInfo(
363     lldb::pid_t pid, ProcessInstanceInfo &process_info) {
364   return m_gdb_client.GetProcessInfo(pid, process_info);
365 }
366 
367 Status PlatformRemoteGDBServer::LaunchProcess(ProcessLaunchInfo &launch_info) {
368   Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PLATFORM));
369   Status error;
370 
371   if (log)
372     log->Printf("PlatformRemoteGDBServer::%s() called", __FUNCTION__);
373 
374   auto num_file_actions = launch_info.GetNumFileActions();
375   for (decltype(num_file_actions) i = 0; i < num_file_actions; ++i) {
376     const auto file_action = launch_info.GetFileActionAtIndex(i);
377     if (file_action->GetAction() != FileAction::eFileActionOpen)
378       continue;
379     switch (file_action->GetFD()) {
380     case STDIN_FILENO:
381       m_gdb_client.SetSTDIN(file_action->GetFileSpec());
382       break;
383     case STDOUT_FILENO:
384       m_gdb_client.SetSTDOUT(file_action->GetFileSpec());
385       break;
386     case STDERR_FILENO:
387       m_gdb_client.SetSTDERR(file_action->GetFileSpec());
388       break;
389     }
390   }
391 
392   m_gdb_client.SetDisableASLR(
393       launch_info.GetFlags().Test(eLaunchFlagDisableASLR));
394   m_gdb_client.SetDetachOnError(
395       launch_info.GetFlags().Test(eLaunchFlagDetachOnError));
396 
397   FileSpec working_dir = launch_info.GetWorkingDirectory();
398   if (working_dir) {
399     m_gdb_client.SetWorkingDir(working_dir);
400   }
401 
402   // Send the environment and the program + arguments after we connect
403   m_gdb_client.SendEnvironment(launch_info.GetEnvironment());
404 
405   ArchSpec arch_spec = launch_info.GetArchitecture();
406   const char *arch_triple = arch_spec.GetTriple().str().c_str();
407 
408   m_gdb_client.SendLaunchArchPacket(arch_triple);
409   if (log)
410     log->Printf(
411         "PlatformRemoteGDBServer::%s() set launch architecture triple to '%s'",
412         __FUNCTION__, arch_triple ? arch_triple : "<NULL>");
413 
414   int arg_packet_err;
415   {
416     // Scope for the scoped timeout object
417     process_gdb_remote::GDBRemoteCommunication::ScopedTimeout timeout(
418         m_gdb_client, std::chrono::seconds(5));
419     arg_packet_err = m_gdb_client.SendArgumentsPacket(launch_info);
420   }
421 
422   if (arg_packet_err == 0) {
423     std::string error_str;
424     if (m_gdb_client.GetLaunchSuccess(error_str)) {
425       const auto pid = m_gdb_client.GetCurrentProcessID(false);
426       if (pid != LLDB_INVALID_PROCESS_ID) {
427         launch_info.SetProcessID(pid);
428         if (log)
429           log->Printf("PlatformRemoteGDBServer::%s() pid %" PRIu64
430                       " launched successfully",
431                       __FUNCTION__, pid);
432       } else {
433         if (log)
434           log->Printf("PlatformRemoteGDBServer::%s() launch succeeded but we "
435                       "didn't get a valid process id back!",
436                       __FUNCTION__);
437         error.SetErrorString("failed to get PID");
438       }
439     } else {
440       error.SetErrorString(error_str.c_str());
441       if (log)
442         log->Printf("PlatformRemoteGDBServer::%s() launch failed: %s",
443                     __FUNCTION__, error.AsCString());
444     }
445   } else {
446     error.SetErrorStringWithFormat("'A' packet returned an error: %i",
447                                    arg_packet_err);
448   }
449   return error;
450 }
451 
452 Status PlatformRemoteGDBServer::KillProcess(const lldb::pid_t pid) {
453   if (!KillSpawnedProcess(pid))
454     return Status("failed to kill remote spawned process");
455   return Status();
456 }
457 
458 lldb::ProcessSP PlatformRemoteGDBServer::DebugProcess(
459     ProcessLaunchInfo &launch_info, Debugger &debugger,
460     Target *target, // Can be NULL, if NULL create a new target, else use
461                     // existing one
462     Status &error) {
463   lldb::ProcessSP process_sp;
464   if (IsRemote()) {
465     if (IsConnected()) {
466       lldb::pid_t debugserver_pid = LLDB_INVALID_PROCESS_ID;
467       std::string connect_url;
468       if (!LaunchGDBServer(debugserver_pid, connect_url)) {
469         error.SetErrorStringWithFormat("unable to launch a GDB server on '%s'",
470                                        GetHostname());
471       } else {
472         if (target == NULL) {
473           TargetSP new_target_sp;
474 
475           error = debugger.GetTargetList().CreateTarget(
476               debugger, "", "", eLoadDependentsNo, NULL, new_target_sp);
477           target = new_target_sp.get();
478         } else
479           error.Clear();
480 
481         if (target && error.Success()) {
482           debugger.GetTargetList().SetSelectedTarget(target);
483 
484           // The darwin always currently uses the GDB remote debugger plug-in
485           // so even when debugging locally we are debugging remotely!
486           process_sp = target->CreateProcess(launch_info.GetListener(),
487                                              "gdb-remote", NULL);
488 
489           if (process_sp) {
490             error = process_sp->ConnectRemote(nullptr, connect_url.c_str());
491             // Retry the connect remote one time...
492             if (error.Fail())
493               error = process_sp->ConnectRemote(nullptr, connect_url.c_str());
494             if (error.Success())
495               error = process_sp->Launch(launch_info);
496             else if (debugserver_pid != LLDB_INVALID_PROCESS_ID) {
497               printf("error: connect remote failed (%s)\n", error.AsCString());
498               KillSpawnedProcess(debugserver_pid);
499             }
500           }
501         }
502       }
503     } else {
504       error.SetErrorString("not connected to remote gdb server");
505     }
506   }
507   return process_sp;
508 }
509 
510 bool PlatformRemoteGDBServer::LaunchGDBServer(lldb::pid_t &pid,
511                                               std::string &connect_url) {
512   ArchSpec remote_arch = GetRemoteSystemArchitecture();
513   llvm::Triple &remote_triple = remote_arch.GetTriple();
514 
515   uint16_t port = 0;
516   std::string socket_name;
517   bool launch_result = false;
518   if (remote_triple.getVendor() == llvm::Triple::Apple &&
519       remote_triple.getOS() == llvm::Triple::IOS) {
520     // When remote debugging to iOS, we use a USB mux that always talks to
521     // localhost, so we will need the remote debugserver to accept connections
522     // only from localhost, no matter what our current hostname is
523     launch_result =
524         m_gdb_client.LaunchGDBServer("127.0.0.1", pid, port, socket_name);
525   } else {
526     // All other hosts should use their actual hostname
527     launch_result =
528         m_gdb_client.LaunchGDBServer(nullptr, pid, port, socket_name);
529   }
530 
531   if (!launch_result)
532     return false;
533 
534   connect_url =
535       MakeGdbServerUrl(m_platform_scheme, m_platform_hostname, port,
536                        (socket_name.empty()) ? nullptr : socket_name.c_str());
537   return true;
538 }
539 
540 bool PlatformRemoteGDBServer::KillSpawnedProcess(lldb::pid_t pid) {
541   return m_gdb_client.KillSpawnedProcess(pid);
542 }
543 
544 lldb::ProcessSP PlatformRemoteGDBServer::Attach(
545     ProcessAttachInfo &attach_info, Debugger &debugger,
546     Target *target, // Can be NULL, if NULL create a new target, else use
547                     // existing one
548     Status &error) {
549   lldb::ProcessSP process_sp;
550   if (IsRemote()) {
551     if (IsConnected()) {
552       lldb::pid_t debugserver_pid = LLDB_INVALID_PROCESS_ID;
553       std::string connect_url;
554       if (!LaunchGDBServer(debugserver_pid, connect_url)) {
555         error.SetErrorStringWithFormat("unable to launch a GDB server on '%s'",
556                                        GetHostname());
557       } else {
558         if (target == NULL) {
559           TargetSP new_target_sp;
560 
561           error = debugger.GetTargetList().CreateTarget(
562               debugger, "", "", eLoadDependentsNo, NULL, new_target_sp);
563           target = new_target_sp.get();
564         } else
565           error.Clear();
566 
567         if (target && error.Success()) {
568           debugger.GetTargetList().SetSelectedTarget(target);
569 
570           // The darwin always currently uses the GDB remote debugger plug-in
571           // so even when debugging locally we are debugging remotely!
572           process_sp = target->CreateProcess(
573               attach_info.GetListenerForProcess(debugger), "gdb-remote", NULL);
574           if (process_sp) {
575             error = process_sp->ConnectRemote(nullptr, connect_url.c_str());
576             if (error.Success()) {
577               ListenerSP listener_sp = attach_info.GetHijackListener();
578               if (listener_sp)
579                 process_sp->HijackProcessEvents(listener_sp);
580               error = process_sp->Attach(attach_info);
581             }
582 
583             if (error.Fail() && debugserver_pid != LLDB_INVALID_PROCESS_ID) {
584               KillSpawnedProcess(debugserver_pid);
585             }
586           }
587         }
588       }
589     } else {
590       error.SetErrorString("not connected to remote gdb server");
591     }
592   }
593   return process_sp;
594 }
595 
596 Status PlatformRemoteGDBServer::MakeDirectory(const FileSpec &file_spec,
597                                               uint32_t mode) {
598   Status error = m_gdb_client.MakeDirectory(file_spec, mode);
599   Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
600   if (log)
601     log->Printf("PlatformRemoteGDBServer::MakeDirectory(path='%s', mode=%o) "
602                 "error = %u (%s)",
603                 file_spec.GetCString(), mode, error.GetError(),
604                 error.AsCString());
605   return error;
606 }
607 
608 Status PlatformRemoteGDBServer::GetFilePermissions(const FileSpec &file_spec,
609                                                    uint32_t &file_permissions) {
610   Status error = m_gdb_client.GetFilePermissions(file_spec, file_permissions);
611   Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
612   if (log)
613     log->Printf("PlatformRemoteGDBServer::GetFilePermissions(path='%s', "
614                 "file_permissions=%o) error = %u (%s)",
615                 file_spec.GetCString(), file_permissions, error.GetError(),
616                 error.AsCString());
617   return error;
618 }
619 
620 Status PlatformRemoteGDBServer::SetFilePermissions(const FileSpec &file_spec,
621                                                    uint32_t file_permissions) {
622   Status error = m_gdb_client.SetFilePermissions(file_spec, file_permissions);
623   Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
624   if (log)
625     log->Printf("PlatformRemoteGDBServer::SetFilePermissions(path='%s', "
626                 "file_permissions=%o) error = %u (%s)",
627                 file_spec.GetCString(), file_permissions, error.GetError(),
628                 error.AsCString());
629   return error;
630 }
631 
632 lldb::user_id_t PlatformRemoteGDBServer::OpenFile(const FileSpec &file_spec,
633                                                   uint32_t flags, uint32_t mode,
634                                                   Status &error) {
635   return m_gdb_client.OpenFile(file_spec, flags, mode, error);
636 }
637 
638 bool PlatformRemoteGDBServer::CloseFile(lldb::user_id_t fd, Status &error) {
639   return m_gdb_client.CloseFile(fd, error);
640 }
641 
642 lldb::user_id_t
643 PlatformRemoteGDBServer::GetFileSize(const FileSpec &file_spec) {
644   return m_gdb_client.GetFileSize(file_spec);
645 }
646 
647 uint64_t PlatformRemoteGDBServer::ReadFile(lldb::user_id_t fd, uint64_t offset,
648                                            void *dst, uint64_t dst_len,
649                                            Status &error) {
650   return m_gdb_client.ReadFile(fd, offset, dst, dst_len, error);
651 }
652 
653 uint64_t PlatformRemoteGDBServer::WriteFile(lldb::user_id_t fd, uint64_t offset,
654                                             const void *src, uint64_t src_len,
655                                             Status &error) {
656   return m_gdb_client.WriteFile(fd, offset, src, src_len, error);
657 }
658 
659 Status PlatformRemoteGDBServer::PutFile(const FileSpec &source,
660                                         const FileSpec &destination,
661                                         uint32_t uid, uint32_t gid) {
662   return Platform::PutFile(source, destination, uid, gid);
663 }
664 
665 Status PlatformRemoteGDBServer::CreateSymlink(
666     const FileSpec &src, // The name of the link is in src
667     const FileSpec &dst) // The symlink points to dst
668 {
669   Status error = m_gdb_client.CreateSymlink(src, dst);
670   Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
671   if (log)
672     log->Printf("PlatformRemoteGDBServer::CreateSymlink(src='%s', dst='%s') "
673                 "error = %u (%s)",
674                 src.GetCString(), dst.GetCString(), error.GetError(),
675                 error.AsCString());
676   return error;
677 }
678 
679 Status PlatformRemoteGDBServer::Unlink(const FileSpec &file_spec) {
680   Status error = m_gdb_client.Unlink(file_spec);
681   Log *log = GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM);
682   if (log)
683     log->Printf("PlatformRemoteGDBServer::Unlink(path='%s') error = %u (%s)",
684                 file_spec.GetCString(), error.GetError(), error.AsCString());
685   return error;
686 }
687 
688 bool PlatformRemoteGDBServer::GetFileExists(const FileSpec &file_spec) {
689   return m_gdb_client.GetFileExists(file_spec);
690 }
691 
692 Status PlatformRemoteGDBServer::RunShellCommand(
693     const char *command, // Shouldn't be NULL
694     const FileSpec &
695         working_dir, // Pass empty FileSpec to use the current working directory
696     int *status_ptr, // Pass NULL if you don't want the process exit status
697     int *signo_ptr,  // Pass NULL if you don't want the signal that caused the
698                      // process to exit
699     std::string
700         *command_output, // Pass NULL if you don't want the command output
701     const Timeout<std::micro> &timeout) {
702   return m_gdb_client.RunShellCommand(command, working_dir, status_ptr,
703                                       signo_ptr, command_output, timeout);
704 }
705 
706 void PlatformRemoteGDBServer::CalculateTrapHandlerSymbolNames() {
707   m_trap_handlers.push_back(ConstString("_sigtramp"));
708 }
709 
710 const UnixSignalsSP &PlatformRemoteGDBServer::GetRemoteUnixSignals() {
711   if (!IsConnected())
712     return Platform::GetRemoteUnixSignals();
713 
714   if (m_remote_signals_sp)
715     return m_remote_signals_sp;
716 
717   // If packet not implemented or JSON failed to parse, we'll guess the signal
718   // set based on the remote architecture.
719   m_remote_signals_sp = UnixSignals::Create(GetRemoteSystemArchitecture());
720 
721   StringExtractorGDBRemote response;
722   auto result = m_gdb_client.SendPacketAndWaitForResponse("jSignalsInfo",
723                                                           response, false);
724 
725   if (result != decltype(result)::Success ||
726       response.GetResponseType() != response.eResponse)
727     return m_remote_signals_sp;
728 
729   auto object_sp = StructuredData::ParseJSON(response.GetStringRef());
730   if (!object_sp || !object_sp->IsValid())
731     return m_remote_signals_sp;
732 
733   auto array_sp = object_sp->GetAsArray();
734   if (!array_sp || !array_sp->IsValid())
735     return m_remote_signals_sp;
736 
737   auto remote_signals_sp = std::make_shared<lldb_private::GDBRemoteSignals>();
738 
739   bool done = array_sp->ForEach(
740       [&remote_signals_sp](StructuredData::Object *object) -> bool {
741         if (!object || !object->IsValid())
742           return false;
743 
744         auto dict = object->GetAsDictionary();
745         if (!dict || !dict->IsValid())
746           return false;
747 
748         // Signal number and signal name are required.
749         int signo;
750         if (!dict->GetValueForKeyAsInteger("signo", signo))
751           return false;
752 
753         llvm::StringRef name;
754         if (!dict->GetValueForKeyAsString("name", name))
755           return false;
756 
757         // We can live without short_name, description, etc.
758         bool suppress{false};
759         auto object_sp = dict->GetValueForKey("suppress");
760         if (object_sp && object_sp->IsValid())
761           suppress = object_sp->GetBooleanValue();
762 
763         bool stop{false};
764         object_sp = dict->GetValueForKey("stop");
765         if (object_sp && object_sp->IsValid())
766           stop = object_sp->GetBooleanValue();
767 
768         bool notify{false};
769         object_sp = dict->GetValueForKey("notify");
770         if (object_sp && object_sp->IsValid())
771           notify = object_sp->GetBooleanValue();
772 
773         std::string description{""};
774         object_sp = dict->GetValueForKey("description");
775         if (object_sp && object_sp->IsValid())
776           description = object_sp->GetStringValue();
777 
778         remote_signals_sp->AddSignal(signo, name.str().c_str(), suppress, stop,
779                                      notify, description.c_str());
780         return true;
781       });
782 
783   if (done)
784     m_remote_signals_sp = std::move(remote_signals_sp);
785 
786   return m_remote_signals_sp;
787 }
788 
789 std::string PlatformRemoteGDBServer::MakeGdbServerUrl(
790     const std::string &platform_scheme, const std::string &platform_hostname,
791     uint16_t port, const char *socket_name) {
792   const char *override_scheme =
793       getenv("LLDB_PLATFORM_REMOTE_GDB_SERVER_SCHEME");
794   const char *override_hostname =
795       getenv("LLDB_PLATFORM_REMOTE_GDB_SERVER_HOSTNAME");
796   const char *port_offset_c_str =
797       getenv("LLDB_PLATFORM_REMOTE_GDB_SERVER_PORT_OFFSET");
798   int port_offset = port_offset_c_str ? ::atoi(port_offset_c_str) : 0;
799 
800   return MakeUrl(override_scheme ? override_scheme : platform_scheme.c_str(),
801                  override_hostname ? override_hostname
802                                    : platform_hostname.c_str(),
803                  port + port_offset, socket_name);
804 }
805 
806 std::string PlatformRemoteGDBServer::MakeUrl(const char *scheme,
807                                              const char *hostname,
808                                              uint16_t port, const char *path) {
809   StreamString result;
810   result.Printf("%s://%s", scheme, hostname);
811   if (port != 0)
812     result.Printf(":%u", port);
813   if (path)
814     result.Write(path, strlen(path));
815   return result.GetString();
816 }
817 
818 lldb::ProcessSP PlatformRemoteGDBServer::ConnectProcess(
819     llvm::StringRef connect_url, llvm::StringRef plugin_name,
820     lldb_private::Debugger &debugger, lldb_private::Target *target,
821     lldb_private::Status &error) {
822   if (!IsRemote() || !IsConnected()) {
823     error.SetErrorString("Not connected to remote gdb server");
824     return nullptr;
825   }
826   return Platform::ConnectProcess(connect_url, plugin_name, debugger, target,
827                                   error);
828 }
829 
830 size_t PlatformRemoteGDBServer::ConnectToWaitingProcesses(Debugger &debugger,
831                                                           Status &error) {
832   std::vector<std::string> connection_urls;
833   GetPendingGdbServerList(connection_urls);
834 
835   for (size_t i = 0; i < connection_urls.size(); ++i) {
836     ConnectProcess(connection_urls[i].c_str(), "", debugger, nullptr, error);
837     if (error.Fail())
838       return i; // We already connected to i process succsessfully
839   }
840   return connection_urls.size();
841 }
842 
843 size_t PlatformRemoteGDBServer::GetPendingGdbServerList(
844     std::vector<std::string> &connection_urls) {
845   std::vector<std::pair<uint16_t, std::string>> remote_servers;
846   m_gdb_client.QueryGDBServer(remote_servers);
847   for (const auto &gdbserver : remote_servers) {
848     const char *socket_name_cstr =
849         gdbserver.second.empty() ? nullptr : gdbserver.second.c_str();
850     connection_urls.emplace_back(
851         MakeGdbServerUrl(m_platform_scheme, m_platform_hostname,
852                          gdbserver.first, socket_name_cstr));
853   }
854   return connection_urls.size();
855 }
856