xref: /llvm-project/lldb/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.cpp (revision 0642cd768b80665585c8500bed2933a3b99123dc)
1 //===-- PlatformRemoteGDBServer.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 "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/Host/ConnectionFileDescriptor.h"
19 #include "lldb/Host/Host.h"
20 #include "lldb/Host/HostInfo.h"
21 #include "lldb/Host/PosixApi.h"
22 #include "lldb/Target/Process.h"
23 #include "lldb/Target/Target.h"
24 #include "lldb/Utility/FileSpec.h"
25 #include "lldb/Utility/LLDBLog.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 #include "llvm/ADT/StringSet.h"
32 #include "llvm/Support/FormatAdapters.h"
33 
34 #include "Plugins/Process/Utility/GDBRemoteSignals.h"
35 #include "Plugins/Process/gdb-remote/ProcessGDBRemote.h"
36 #include <mutex>
37 #include <optional>
38 
39 using namespace lldb;
40 using namespace lldb_private;
41 using namespace lldb_private::platform_gdb_server;
42 
43 LLDB_PLUGIN_DEFINE_ADV(PlatformRemoteGDBServer, PlatformGDB)
44 
45 static bool g_initialized = false;
46 // UnixSignals does not store the signal names or descriptions itself.
47 // It holds onto StringRefs. Becaue we may get signal information dynamically
48 // from the remote, these strings need persistent storage client-side.
49 static std::mutex g_signal_string_mutex;
50 static llvm::StringSet<> g_signal_string_storage;
51 
52 void PlatformRemoteGDBServer::Initialize() {
53   Platform::Initialize();
54 
55   if (!g_initialized) {
56     g_initialized = true;
57     PluginManager::RegisterPlugin(
58         PlatformRemoteGDBServer::GetPluginNameStatic(),
59         PlatformRemoteGDBServer::GetDescriptionStatic(),
60         PlatformRemoteGDBServer::CreateInstance);
61   }
62 }
63 
64 void PlatformRemoteGDBServer::Terminate() {
65   if (g_initialized) {
66     g_initialized = false;
67     PluginManager::UnregisterPlugin(PlatformRemoteGDBServer::CreateInstance);
68   }
69 
70   Platform::Terminate();
71 }
72 
73 PlatformSP PlatformRemoteGDBServer::CreateInstance(bool force,
74                                                    const ArchSpec *arch) {
75   bool create = force;
76   if (!create) {
77     create = !arch->TripleVendorWasSpecified() && !arch->TripleOSWasSpecified();
78   }
79   if (create)
80     return PlatformSP(new PlatformRemoteGDBServer());
81   return PlatformSP();
82 }
83 
84 llvm::StringRef PlatformRemoteGDBServer::GetDescriptionStatic() {
85   return "A platform that uses the GDB remote protocol as the communication "
86          "transport.";
87 }
88 
89 llvm::StringRef PlatformRemoteGDBServer::GetDescription() {
90   if (m_platform_description.empty()) {
91     if (IsConnected()) {
92       // Send the get description packet
93     }
94   }
95 
96   if (!m_platform_description.empty())
97     return m_platform_description.c_str();
98   return GetDescriptionStatic();
99 }
100 
101 bool PlatformRemoteGDBServer::GetModuleSpec(const FileSpec &module_file_spec,
102                                             const ArchSpec &arch,
103                                             ModuleSpec &module_spec) {
104   Log *log = GetLog(LLDBLog::Platform);
105 
106   const auto module_path = module_file_spec.GetPath(false);
107 
108   if (!m_gdb_client_up ||
109       !m_gdb_client_up->GetModuleInfo(module_file_spec, arch, module_spec)) {
110     LLDB_LOGF(
111         log,
112         "PlatformRemoteGDBServer::%s - failed to get module info for %s:%s",
113         __FUNCTION__, module_path.c_str(),
114         arch.GetTriple().getTriple().c_str());
115     return false;
116   }
117 
118   if (log) {
119     StreamString stream;
120     module_spec.Dump(stream);
121     LLDB_LOGF(log,
122               "PlatformRemoteGDBServer::%s - got module info for (%s:%s) : %s",
123               __FUNCTION__, module_path.c_str(),
124               arch.GetTriple().getTriple().c_str(), stream.GetData());
125   }
126 
127   return true;
128 }
129 
130 Status PlatformRemoteGDBServer::GetFileWithUUID(const FileSpec &platform_file,
131                                                 const UUID *uuid_ptr,
132                                                 FileSpec &local_file) {
133   // Default to the local case
134   local_file = platform_file;
135   return Status();
136 }
137 
138 /// Default Constructor
139 PlatformRemoteGDBServer::PlatformRemoteGDBServer()
140     : Platform(/*is_host=*/false) {}
141 
142 /// Destructor.
143 ///
144 /// The destructor is virtual since this class is designed to be
145 /// inherited from by the plug-in instance.
146 PlatformRemoteGDBServer::~PlatformRemoteGDBServer() = default;
147 
148 size_t PlatformRemoteGDBServer::GetSoftwareBreakpointTrapOpcode(
149     Target &target, BreakpointSite *bp_site) {
150   // This isn't needed if the z/Z packets are supported in the GDB remote
151   // server. But we might need a packet to detect this.
152   return 0;
153 }
154 
155 bool PlatformRemoteGDBServer::GetRemoteOSVersion() {
156   if (m_gdb_client_up)
157     m_os_version = m_gdb_client_up->GetOSVersion();
158   return !m_os_version.empty();
159 }
160 
161 std::optional<std::string> PlatformRemoteGDBServer::GetRemoteOSBuildString() {
162   if (!m_gdb_client_up)
163     return std::nullopt;
164   return m_gdb_client_up->GetOSBuildString();
165 }
166 
167 std::optional<std::string>
168 PlatformRemoteGDBServer::GetRemoteOSKernelDescription() {
169   if (!m_gdb_client_up)
170     return std::nullopt;
171   return m_gdb_client_up->GetOSKernelDescription();
172 }
173 
174 // Remote Platform subclasses need to override this function
175 ArchSpec PlatformRemoteGDBServer::GetRemoteSystemArchitecture() {
176   if (!m_gdb_client_up)
177     return ArchSpec();
178   return m_gdb_client_up->GetSystemArchitecture();
179 }
180 
181 FileSpec PlatformRemoteGDBServer::GetRemoteWorkingDirectory() {
182   if (IsConnected()) {
183     Log *log = GetLog(LLDBLog::Platform);
184     FileSpec working_dir;
185     if (m_gdb_client_up->GetWorkingDir(working_dir) && log)
186       LLDB_LOGF(log,
187                 "PlatformRemoteGDBServer::GetRemoteWorkingDirectory() -> '%s'",
188                 working_dir.GetPath().c_str());
189     return working_dir;
190   } else {
191     return Platform::GetRemoteWorkingDirectory();
192   }
193 }
194 
195 bool PlatformRemoteGDBServer::SetRemoteWorkingDirectory(
196     const FileSpec &working_dir) {
197   if (IsConnected()) {
198     // Clear the working directory it case it doesn't get set correctly. This
199     // will for use to re-read it
200     Log *log = GetLog(LLDBLog::Platform);
201     LLDB_LOGF(log, "PlatformRemoteGDBServer::SetRemoteWorkingDirectory('%s')",
202               working_dir.GetPath().c_str());
203     return m_gdb_client_up->SetWorkingDir(working_dir) == 0;
204   } else
205     return Platform::SetRemoteWorkingDirectory(working_dir);
206 }
207 
208 bool PlatformRemoteGDBServer::IsConnected() const {
209   if (m_gdb_client_up) {
210     assert(m_gdb_client_up->IsConnected());
211     return true;
212   }
213   return false;
214 }
215 
216 Status PlatformRemoteGDBServer::ConnectRemote(Args &args) {
217   Status error;
218   if (IsConnected())
219     return Status::FromErrorStringWithFormat(
220         "the platform is already connected to '%s', "
221         "execute 'platform disconnect' to close the "
222         "current connection",
223         GetHostname());
224 
225   if (args.GetArgumentCount() != 1)
226     return Status::FromErrorString(
227         "\"platform connect\" takes a single argument: <connect-url>");
228 
229   const char *url = args.GetArgumentAtIndex(0);
230   if (!url)
231     return Status::FromErrorString("URL is null.");
232 
233   std::optional<URI> parsed_url = URI::Parse(url);
234   if (!parsed_url)
235     return Status::FromErrorStringWithFormat("Invalid URL: %s", url);
236 
237   // We're going to reuse the hostname when we connect to the debugserver.
238   m_platform_scheme = parsed_url->scheme.str();
239   m_platform_hostname = parsed_url->hostname.str();
240 
241   auto client_up =
242       std::make_unique<process_gdb_remote::GDBRemoteCommunicationClient>();
243   client_up->SetPacketTimeout(
244       process_gdb_remote::ProcessGDBRemote::GetPacketTimeout());
245   client_up->SetConnection(std::make_unique<ConnectionFileDescriptor>());
246   client_up->Connect(url, &error);
247 
248   if (error.Fail())
249     return error;
250 
251   if (client_up->HandshakeWithServer(&error)) {
252     m_gdb_client_up = std::move(client_up);
253     m_gdb_client_up->GetHostInfo();
254     // If a working directory was set prior to connecting, send it down
255     // now.
256     if (m_working_dir)
257       m_gdb_client_up->SetWorkingDir(m_working_dir);
258 
259     m_supported_architectures.clear();
260     ArchSpec remote_arch = m_gdb_client_up->GetSystemArchitecture();
261     if (remote_arch) {
262       m_supported_architectures.push_back(remote_arch);
263       if (remote_arch.GetTriple().isArch64Bit())
264         m_supported_architectures.push_back(
265             ArchSpec(remote_arch.GetTriple().get32BitArchVariant()));
266     }
267   } else {
268     client_up->Disconnect();
269     if (error.Success())
270       error = Status::FromErrorString("handshake failed");
271   }
272   return error;
273 }
274 
275 Status PlatformRemoteGDBServer::DisconnectRemote() {
276   Status error;
277   m_gdb_client_up.reset();
278   m_remote_signals_sp.reset();
279   return error;
280 }
281 
282 const char *PlatformRemoteGDBServer::GetHostname() {
283   if (m_gdb_client_up)
284     m_gdb_client_up->GetHostname(m_hostname);
285   if (m_hostname.empty())
286     return nullptr;
287   return m_hostname.c_str();
288 }
289 
290 std::optional<std::string>
291 PlatformRemoteGDBServer::DoGetUserName(UserIDResolver::id_t uid) {
292   std::string name;
293   if (m_gdb_client_up && m_gdb_client_up->GetUserName(uid, name))
294     return std::move(name);
295   return std::nullopt;
296 }
297 
298 std::optional<std::string>
299 PlatformRemoteGDBServer::DoGetGroupName(UserIDResolver::id_t gid) {
300   std::string name;
301   if (m_gdb_client_up && m_gdb_client_up->GetGroupName(gid, name))
302     return std::move(name);
303   return std::nullopt;
304 }
305 
306 uint32_t PlatformRemoteGDBServer::FindProcesses(
307     const ProcessInstanceInfoMatch &match_info,
308     ProcessInstanceInfoList &process_infos) {
309   if (m_gdb_client_up)
310     return m_gdb_client_up->FindProcesses(match_info, process_infos);
311   return 0;
312 }
313 
314 bool PlatformRemoteGDBServer::GetProcessInfo(
315     lldb::pid_t pid, ProcessInstanceInfo &process_info) {
316   if (m_gdb_client_up)
317     return m_gdb_client_up->GetProcessInfo(pid, process_info);
318   return false;
319 }
320 
321 Status PlatformRemoteGDBServer::LaunchProcess(ProcessLaunchInfo &launch_info) {
322   Log *log = GetLog(LLDBLog::Platform);
323   Status error;
324 
325   LLDB_LOGF(log, "PlatformRemoteGDBServer::%s() called", __FUNCTION__);
326 
327   if (!IsConnected())
328     return Status::FromErrorStringWithFormat("Not connected.");
329   auto num_file_actions = launch_info.GetNumFileActions();
330   for (decltype(num_file_actions) i = 0; i < num_file_actions; ++i) {
331     const auto file_action = launch_info.GetFileActionAtIndex(i);
332     if (file_action->GetAction() != FileAction::eFileActionOpen)
333       continue;
334     switch (file_action->GetFD()) {
335     case STDIN_FILENO:
336       m_gdb_client_up->SetSTDIN(file_action->GetFileSpec());
337       break;
338     case STDOUT_FILENO:
339       m_gdb_client_up->SetSTDOUT(file_action->GetFileSpec());
340       break;
341     case STDERR_FILENO:
342       m_gdb_client_up->SetSTDERR(file_action->GetFileSpec());
343       break;
344     }
345   }
346 
347   m_gdb_client_up->SetDisableASLR(
348       launch_info.GetFlags().Test(eLaunchFlagDisableASLR));
349   m_gdb_client_up->SetDetachOnError(
350       launch_info.GetFlags().Test(eLaunchFlagDetachOnError));
351 
352   FileSpec working_dir = launch_info.GetWorkingDirectory();
353   if (working_dir) {
354     m_gdb_client_up->SetWorkingDir(working_dir);
355   }
356 
357   // Send the environment and the program + arguments after we connect
358   m_gdb_client_up->SendEnvironment(launch_info.GetEnvironment());
359 
360   ArchSpec arch_spec = launch_info.GetArchitecture();
361   const char *arch_triple = arch_spec.GetTriple().str().c_str();
362 
363   m_gdb_client_up->SendLaunchArchPacket(arch_triple);
364   LLDB_LOGF(
365       log,
366       "PlatformRemoteGDBServer::%s() set launch architecture triple to '%s'",
367       __FUNCTION__, arch_triple ? arch_triple : "<NULL>");
368 
369   {
370     // Scope for the scoped timeout object
371     process_gdb_remote::GDBRemoteCommunication::ScopedTimeout timeout(
372         *m_gdb_client_up, std::chrono::seconds(5));
373     // Since we can't send argv0 separate from the executable path, we need to
374     // make sure to use the actual executable path found in the launch_info...
375     Args args = launch_info.GetArguments();
376     if (FileSpec exe_file = launch_info.GetExecutableFile())
377       args.ReplaceArgumentAtIndex(0, exe_file.GetPath(false));
378     if (llvm::Error err = m_gdb_client_up->LaunchProcess(args)) {
379       error = Status::FromErrorStringWithFormatv(
380           "Cannot launch '{0}': {1}", args.GetArgumentAtIndex(0),
381           llvm::fmt_consume(std::move(err)));
382       return error;
383     }
384   }
385 
386   const auto pid = m_gdb_client_up->GetCurrentProcessID(false);
387   if (pid != LLDB_INVALID_PROCESS_ID) {
388     launch_info.SetProcessID(pid);
389     LLDB_LOGF(log,
390               "PlatformRemoteGDBServer::%s() pid %" PRIu64
391               " launched successfully",
392               __FUNCTION__, pid);
393   } else {
394     LLDB_LOGF(log,
395               "PlatformRemoteGDBServer::%s() launch succeeded but we "
396               "didn't get a valid process id back!",
397               __FUNCTION__);
398     error = Status::FromErrorString("failed to get PID");
399   }
400   return error;
401 }
402 
403 Status PlatformRemoteGDBServer::KillProcess(const lldb::pid_t pid) {
404   if (!KillSpawnedProcess(pid))
405     return Status::FromErrorStringWithFormat(
406         "failed to kill remote spawned process");
407   return Status();
408 }
409 
410 lldb::ProcessSP
411 PlatformRemoteGDBServer::DebugProcess(ProcessLaunchInfo &launch_info,
412                                       Debugger &debugger, Target &target,
413                                       Status &error) {
414   lldb::ProcessSP process_sp;
415   if (IsRemote()) {
416     if (IsConnected()) {
417       lldb::pid_t debugserver_pid = LLDB_INVALID_PROCESS_ID;
418       std::string connect_url;
419       if (!LaunchGDBServer(debugserver_pid, connect_url)) {
420         error = Status::FromErrorStringWithFormat(
421             "unable to launch a GDB server on '%s'", GetHostname());
422       } else {
423         // The darwin always currently uses the GDB remote debugger plug-in
424         // so even when debugging locally we are debugging remotely!
425         process_sp = target.CreateProcess(launch_info.GetListener(),
426                                           "gdb-remote", nullptr, true);
427 
428         if (process_sp) {
429           process_sp->HijackProcessEvents(launch_info.GetHijackListener());
430           process_sp->SetShadowListener(launch_info.GetShadowListener());
431 
432           error = process_sp->ConnectRemote(connect_url.c_str());
433           // Retry the connect remote one time...
434           if (error.Fail())
435             error = process_sp->ConnectRemote(connect_url.c_str());
436           if (error.Success())
437             error = process_sp->Launch(launch_info);
438           else if (debugserver_pid != LLDB_INVALID_PROCESS_ID) {
439             printf("error: connect remote failed (%s)\n", error.AsCString());
440             KillSpawnedProcess(debugserver_pid);
441           }
442         }
443       }
444     } else {
445       error = Status::FromErrorString("not connected to remote gdb server");
446     }
447   }
448   return process_sp;
449 }
450 
451 bool PlatformRemoteGDBServer::LaunchGDBServer(lldb::pid_t &pid,
452                                               std::string &connect_url) {
453   assert(IsConnected());
454 
455   ArchSpec remote_arch = GetRemoteSystemArchitecture();
456   llvm::Triple &remote_triple = remote_arch.GetTriple();
457 
458   uint16_t port = 0;
459   std::string socket_name;
460   bool launch_result = false;
461   if (remote_triple.getVendor() == llvm::Triple::Apple &&
462       remote_triple.getOS() == llvm::Triple::IOS) {
463     // When remote debugging to iOS, we use a USB mux that always talks to
464     // localhost, so we will need the remote debugserver to accept connections
465     // only from localhost, no matter what our current hostname is
466     launch_result =
467         m_gdb_client_up->LaunchGDBServer("127.0.0.1", pid, port, socket_name);
468   } else {
469     // All other hosts should use their actual hostname
470     launch_result =
471         m_gdb_client_up->LaunchGDBServer(nullptr, pid, port, socket_name);
472   }
473 
474   if (!launch_result)
475     return false;
476 
477   connect_url =
478       MakeGdbServerUrl(m_platform_scheme, m_platform_hostname, port,
479                        (socket_name.empty()) ? nullptr : socket_name.c_str());
480   return true;
481 }
482 
483 bool PlatformRemoteGDBServer::KillSpawnedProcess(lldb::pid_t pid) {
484   assert(IsConnected());
485   return m_gdb_client_up->KillSpawnedProcess(pid);
486 }
487 
488 lldb::ProcessSP PlatformRemoteGDBServer::Attach(
489     ProcessAttachInfo &attach_info, Debugger &debugger,
490     Target *target, // Can be NULL, if NULL create a new target, else use
491                     // existing one
492     Status &error) {
493   lldb::ProcessSP process_sp;
494   if (IsRemote()) {
495     if (IsConnected()) {
496       lldb::pid_t debugserver_pid = LLDB_INVALID_PROCESS_ID;
497       std::string connect_url;
498       if (!LaunchGDBServer(debugserver_pid, connect_url)) {
499         error = Status::FromErrorStringWithFormat(
500             "unable to launch a GDB server on '%s'", GetHostname());
501       } else {
502         if (target == nullptr) {
503           TargetSP new_target_sp;
504 
505           error = debugger.GetTargetList().CreateTarget(
506               debugger, "", "", eLoadDependentsNo, nullptr, new_target_sp);
507           target = new_target_sp.get();
508         } else
509           error.Clear();
510 
511         if (target && error.Success()) {
512           // The darwin always currently uses the GDB remote debugger plug-in
513           // so even when debugging locally we are debugging remotely!
514           process_sp =
515               target->CreateProcess(attach_info.GetListenerForProcess(debugger),
516                                     "gdb-remote", nullptr, true);
517           if (process_sp) {
518             error = process_sp->ConnectRemote(connect_url.c_str());
519             if (error.Success()) {
520               ListenerSP listener_sp = attach_info.GetHijackListener();
521               if (listener_sp)
522                 process_sp->HijackProcessEvents(listener_sp);
523               process_sp->SetShadowListener(attach_info.GetShadowListener());
524               error = process_sp->Attach(attach_info);
525             }
526 
527             if (error.Fail() && debugserver_pid != LLDB_INVALID_PROCESS_ID) {
528               KillSpawnedProcess(debugserver_pid);
529             }
530           }
531         }
532       }
533     } else {
534       error = Status::FromErrorString("not connected to remote gdb server");
535     }
536   }
537   return process_sp;
538 }
539 
540 Status PlatformRemoteGDBServer::MakeDirectory(const FileSpec &file_spec,
541                                               uint32_t mode) {
542   if (!IsConnected())
543     return Status::FromErrorStringWithFormat("Not connected.");
544   Status error = m_gdb_client_up->MakeDirectory(file_spec, mode);
545   Log *log = GetLog(LLDBLog::Platform);
546   LLDB_LOGF(log,
547             "PlatformRemoteGDBServer::MakeDirectory(path='%s', mode=%o) "
548             "error = %u (%s)",
549             file_spec.GetPath().c_str(), mode, error.GetError(),
550             error.AsCString());
551   return error;
552 }
553 
554 Status PlatformRemoteGDBServer::GetFilePermissions(const FileSpec &file_spec,
555                                                    uint32_t &file_permissions) {
556   if (!IsConnected())
557     return Status::FromErrorStringWithFormat("Not connected.");
558   Status error =
559       m_gdb_client_up->GetFilePermissions(file_spec, file_permissions);
560   Log *log = GetLog(LLDBLog::Platform);
561   LLDB_LOGF(log,
562             "PlatformRemoteGDBServer::GetFilePermissions(path='%s', "
563             "file_permissions=%o) error = %u (%s)",
564             file_spec.GetPath().c_str(), file_permissions, error.GetError(),
565             error.AsCString());
566   return error;
567 }
568 
569 Status PlatformRemoteGDBServer::SetFilePermissions(const FileSpec &file_spec,
570                                                    uint32_t file_permissions) {
571   if (!IsConnected())
572     return Status::FromErrorStringWithFormat("Not connected.");
573   Status error =
574       m_gdb_client_up->SetFilePermissions(file_spec, file_permissions);
575   Log *log = GetLog(LLDBLog::Platform);
576   LLDB_LOGF(log,
577             "PlatformRemoteGDBServer::SetFilePermissions(path='%s', "
578             "file_permissions=%o) error = %u (%s)",
579             file_spec.GetPath().c_str(), file_permissions, error.GetError(),
580             error.AsCString());
581   return error;
582 }
583 
584 lldb::user_id_t PlatformRemoteGDBServer::OpenFile(const FileSpec &file_spec,
585                                                   File::OpenOptions flags,
586                                                   uint32_t mode,
587                                                   Status &error) {
588   if (IsConnected())
589     return m_gdb_client_up->OpenFile(file_spec, flags, mode, error);
590   return LLDB_INVALID_UID;
591 }
592 
593 bool PlatformRemoteGDBServer::CloseFile(lldb::user_id_t fd, Status &error) {
594   if (IsConnected())
595     return m_gdb_client_up->CloseFile(fd, error);
596   error = Status::FromErrorStringWithFormat("Not connected.");
597   return false;
598 }
599 
600 lldb::user_id_t
601 PlatformRemoteGDBServer::GetFileSize(const FileSpec &file_spec) {
602   if (IsConnected())
603     return m_gdb_client_up->GetFileSize(file_spec);
604   return LLDB_INVALID_UID;
605 }
606 
607 void PlatformRemoteGDBServer::AutoCompleteDiskFileOrDirectory(
608     CompletionRequest &request, bool only_dir) {
609   if (IsConnected())
610     m_gdb_client_up->AutoCompleteDiskFileOrDirectory(request, only_dir);
611 }
612 
613 uint64_t PlatformRemoteGDBServer::ReadFile(lldb::user_id_t fd, uint64_t offset,
614                                            void *dst, uint64_t dst_len,
615                                            Status &error) {
616   if (IsConnected())
617     return m_gdb_client_up->ReadFile(fd, offset, dst, dst_len, error);
618   error = Status::FromErrorStringWithFormat("Not connected.");
619   return 0;
620 }
621 
622 uint64_t PlatformRemoteGDBServer::WriteFile(lldb::user_id_t fd, uint64_t offset,
623                                             const void *src, uint64_t src_len,
624                                             Status &error) {
625   if (IsConnected())
626     return m_gdb_client_up->WriteFile(fd, offset, src, src_len, error);
627   error = Status::FromErrorStringWithFormat("Not connected.");
628   return 0;
629 }
630 
631 Status PlatformRemoteGDBServer::PutFile(const FileSpec &source,
632                                         const FileSpec &destination,
633                                         uint32_t uid, uint32_t gid) {
634   return Platform::PutFile(source, destination, uid, gid);
635 }
636 
637 Status PlatformRemoteGDBServer::CreateSymlink(
638     const FileSpec &src, // The name of the link is in src
639     const FileSpec &dst) // The symlink points to dst
640 {
641   if (!IsConnected())
642     return Status::FromErrorStringWithFormat("Not connected.");
643   Status error = m_gdb_client_up->CreateSymlink(src, dst);
644   Log *log = GetLog(LLDBLog::Platform);
645   LLDB_LOGF(log,
646             "PlatformRemoteGDBServer::CreateSymlink(src='%s', dst='%s') "
647             "error = %u (%s)",
648             src.GetPath().c_str(), dst.GetPath().c_str(), error.GetError(),
649             error.AsCString());
650   return error;
651 }
652 
653 Status PlatformRemoteGDBServer::Unlink(const FileSpec &file_spec) {
654   if (!IsConnected())
655     return Status::FromErrorStringWithFormat("Not connected.");
656   Status error = m_gdb_client_up->Unlink(file_spec);
657   Log *log = GetLog(LLDBLog::Platform);
658   LLDB_LOGF(log, "PlatformRemoteGDBServer::Unlink(path='%s') error = %u (%s)",
659             file_spec.GetPath().c_str(), error.GetError(), error.AsCString());
660   return error;
661 }
662 
663 bool PlatformRemoteGDBServer::GetFileExists(const FileSpec &file_spec) {
664   if (IsConnected())
665     return m_gdb_client_up->GetFileExists(file_spec);
666   return false;
667 }
668 
669 Status PlatformRemoteGDBServer::RunShellCommand(
670     llvm::StringRef shell, llvm::StringRef command,
671     const FileSpec &
672         working_dir, // Pass empty FileSpec to use the current working directory
673     int *status_ptr, // Pass NULL if you don't want the process exit status
674     int *signo_ptr,  // Pass NULL if you don't want the signal that caused the
675                      // process to exit
676     std::string
677         *command_output, // Pass NULL if you don't want the command output
678     const Timeout<std::micro> &timeout) {
679   if (!IsConnected())
680     return Status::FromErrorStringWithFormat("Not connected.");
681   return m_gdb_client_up->RunShellCommand(command, working_dir, status_ptr,
682                                           signo_ptr, command_output, timeout);
683 }
684 
685 llvm::ErrorOr<llvm::MD5::MD5Result>
686 PlatformRemoteGDBServer::CalculateMD5(const FileSpec &file_spec) {
687   if (!IsConnected())
688     return std::make_error_code(std::errc::not_connected);
689 
690   return m_gdb_client_up->CalculateMD5(file_spec);
691 }
692 
693 void PlatformRemoteGDBServer::CalculateTrapHandlerSymbolNames() {
694   m_trap_handlers.push_back(ConstString("_sigtramp"));
695 }
696 
697 const UnixSignalsSP &PlatformRemoteGDBServer::GetRemoteUnixSignals() {
698   if (!IsConnected())
699     return Platform::GetRemoteUnixSignals();
700 
701   if (m_remote_signals_sp)
702     return m_remote_signals_sp;
703 
704   // If packet not implemented or JSON failed to parse, we'll guess the signal
705   // set based on the remote architecture.
706   m_remote_signals_sp = UnixSignals::Create(GetRemoteSystemArchitecture());
707 
708   StringExtractorGDBRemote response;
709   auto result =
710       m_gdb_client_up->SendPacketAndWaitForResponse("jSignalsInfo", response);
711 
712   if (result != decltype(result)::Success ||
713       response.GetResponseType() != response.eResponse)
714     return m_remote_signals_sp;
715 
716   auto object_sp = StructuredData::ParseJSON(response.GetStringRef());
717   if (!object_sp || !object_sp->IsValid())
718     return m_remote_signals_sp;
719 
720   auto array_sp = object_sp->GetAsArray();
721   if (!array_sp || !array_sp->IsValid())
722     return m_remote_signals_sp;
723 
724   auto remote_signals_sp = std::make_shared<lldb_private::GDBRemoteSignals>();
725 
726   bool done = array_sp->ForEach(
727       [&remote_signals_sp](StructuredData::Object *object) -> bool {
728         if (!object || !object->IsValid())
729           return false;
730 
731         auto dict = object->GetAsDictionary();
732         if (!dict || !dict->IsValid())
733           return false;
734 
735         // Signal number and signal name are required.
736         uint64_t signo;
737         if (!dict->GetValueForKeyAsInteger("signo", signo))
738           return false;
739 
740         llvm::StringRef name;
741         if (!dict->GetValueForKeyAsString("name", name))
742           return false;
743 
744         // We can live without short_name, description, etc.
745         bool suppress{false};
746         auto object_sp = dict->GetValueForKey("suppress");
747         if (object_sp && object_sp->IsValid())
748           suppress = object_sp->GetBooleanValue();
749 
750         bool stop{false};
751         object_sp = dict->GetValueForKey("stop");
752         if (object_sp && object_sp->IsValid())
753           stop = object_sp->GetBooleanValue();
754 
755         bool notify{false};
756         object_sp = dict->GetValueForKey("notify");
757         if (object_sp && object_sp->IsValid())
758           notify = object_sp->GetBooleanValue();
759 
760         std::string description;
761         object_sp = dict->GetValueForKey("description");
762         if (object_sp && object_sp->IsValid())
763           description = std::string(object_sp->GetStringValue());
764 
765         llvm::StringRef name_backed, description_backed;
766         {
767           std::lock_guard<std::mutex> guard(g_signal_string_mutex);
768           name_backed =
769               g_signal_string_storage.insert(name).first->getKeyData();
770           if (!description.empty())
771             description_backed =
772                 g_signal_string_storage.insert(description).first->getKeyData();
773         }
774 
775         remote_signals_sp->AddSignal(signo, name_backed, suppress, stop, notify,
776                                      description_backed);
777         return true;
778       });
779 
780   if (done)
781     m_remote_signals_sp = std::move(remote_signals_sp);
782 
783   return m_remote_signals_sp;
784 }
785 
786 std::string PlatformRemoteGDBServer::MakeGdbServerUrl(
787     const std::string &platform_scheme, const std::string &platform_hostname,
788     uint16_t port, const char *socket_name) {
789   const char *override_scheme =
790       getenv("LLDB_PLATFORM_REMOTE_GDB_SERVER_SCHEME");
791   const char *override_hostname =
792       getenv("LLDB_PLATFORM_REMOTE_GDB_SERVER_HOSTNAME");
793   const char *port_offset_c_str =
794       getenv("LLDB_PLATFORM_REMOTE_GDB_SERVER_PORT_OFFSET");
795   int port_offset = port_offset_c_str ? ::atoi(port_offset_c_str) : 0;
796 
797   return MakeUrl(override_scheme ? override_scheme : platform_scheme.c_str(),
798                  override_hostname ? override_hostname
799                                    : platform_hostname.c_str(),
800                  port + port_offset, socket_name);
801 }
802 
803 std::string PlatformRemoteGDBServer::MakeUrl(const char *scheme,
804                                              const char *hostname,
805                                              uint16_t port, const char *path) {
806   StreamString result;
807   result.Printf("%s://[%s]", scheme, hostname);
808   if (port != 0)
809     result.Printf(":%u", port);
810   if (path)
811     result.Write(path, strlen(path));
812   return std::string(result.GetString());
813 }
814 
815 size_t PlatformRemoteGDBServer::ConnectToWaitingProcesses(Debugger &debugger,
816                                                           Status &error) {
817   std::vector<std::string> connection_urls;
818   GetPendingGdbServerList(connection_urls);
819 
820   for (size_t i = 0; i < connection_urls.size(); ++i) {
821     ConnectProcess(connection_urls[i].c_str(), "gdb-remote", debugger, nullptr, error);
822     if (error.Fail())
823       return i; // We already connected to i process successfully
824   }
825   return connection_urls.size();
826 }
827 
828 size_t PlatformRemoteGDBServer::GetPendingGdbServerList(
829     std::vector<std::string> &connection_urls) {
830   std::vector<std::pair<uint16_t, std::string>> remote_servers;
831   if (!IsConnected())
832     return 0;
833   m_gdb_client_up->QueryGDBServer(remote_servers);
834   for (const auto &gdbserver : remote_servers) {
835     const char *socket_name_cstr =
836         gdbserver.second.empty() ? nullptr : gdbserver.second.c_str();
837     connection_urls.emplace_back(
838         MakeGdbServerUrl(m_platform_scheme, m_platform_hostname,
839                          gdbserver.first, socket_name_cstr));
840   }
841   return connection_urls.size();
842 }
843