1 //===-- PlatformLinux.cpp ---------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/lldb-python.h"
11 
12 #include "PlatformLinux.h"
13 #include "lldb/Host/Config.h"
14 
15 // C Includes
16 #include <stdio.h>
17 #ifndef LLDB_DISABLE_POSIX
18 #include <sys/utsname.h>
19 #endif
20 
21 // C++ Includes
22 // Other libraries and framework includes
23 // Project includes
24 #include "lldb/Breakpoint/BreakpointLocation.h"
25 #include "lldb/Core/Debugger.h"
26 #include "lldb/Core/Error.h"
27 #include "lldb/Core/Log.h"
28 #include "lldb/Core/Module.h"
29 #include "lldb/Core/ModuleList.h"
30 #include "lldb/Core/ModuleSpec.h"
31 #include "lldb/Core/PluginManager.h"
32 #include "lldb/Core/State.h"
33 #include "lldb/Core/StreamString.h"
34 #include "lldb/Host/FileSpec.h"
35 #include "lldb/Host/HostInfo.h"
36 #include "lldb/Interpreter/OptionValueProperties.h"
37 #include "lldb/Interpreter/Property.h"
38 #include "lldb/Target/Target.h"
39 #include "lldb/Target/Process.h"
40 
41 #if defined(__linux__)
42 #include "../../Process/Linux/NativeProcessLinux.h"
43 #endif
44 
45 using namespace lldb;
46 using namespace lldb_private;
47 
48 static uint32_t g_initialize_count = 0;
49 
50 //------------------------------------------------------------------
51 /// Code to handle the PlatformLinux settings
52 //------------------------------------------------------------------
53 
54 namespace
55 {
56     enum
57     {
58         ePropertyUseLlgsForLocal = 0,
59     };
60 
61     const PropertyDefinition*
62     GetStaticPropertyDefinitions ()
63     {
64         static PropertyDefinition
65         g_properties[] =
66         {
67             { "use-llgs-for-local" , OptionValue::eTypeBoolean, true, false, NULL, NULL, "Control whether the platform uses llgs for local debug sessions." },
68             {  NULL        , OptionValue::eTypeInvalid, false, 0  , NULL, NULL, NULL  }
69         };
70 
71         // Allow environment variable to force using llgs-local.
72         if (getenv("PLATFORM_LINUX_FORCE_LLGS_LOCAL"))
73             g_properties[ePropertyUseLlgsForLocal].default_uint_value = true;
74 
75         return g_properties;
76     }
77 }
78 
79 class PlatformLinuxProperties : public Properties
80 {
81 public:
82 
83     static ConstString &
84     GetSettingName ()
85     {
86         static ConstString g_setting_name("linux");
87         return g_setting_name;
88     }
89 
90     PlatformLinuxProperties() :
91     Properties ()
92     {
93         m_collection_sp.reset (new OptionValueProperties(GetSettingName ()));
94         m_collection_sp->Initialize (GetStaticPropertyDefinitions ());
95     }
96 
97     virtual
98     ~PlatformLinuxProperties()
99     {
100     }
101 
102     bool
103     GetUseLlgsForLocal() const
104     {
105         const uint32_t idx = ePropertyUseLlgsForLocal;
106         return m_collection_sp->GetPropertyAtIndexAsBoolean (NULL, idx, GetStaticPropertyDefinitions()[idx].default_uint_value != 0);
107     }
108 };
109 
110 typedef std::shared_ptr<PlatformLinuxProperties> PlatformLinuxPropertiesSP;
111 
112 static const PlatformLinuxPropertiesSP &
113 GetGlobalProperties()
114 {
115     static PlatformLinuxPropertiesSP g_settings_sp;
116     if (!g_settings_sp)
117         g_settings_sp.reset (new PlatformLinuxProperties ());
118     return g_settings_sp;
119 }
120 
121 void
122 PlatformLinux::DebuggerInitialize (lldb_private::Debugger &debugger)
123 {
124     if (!PluginManager::GetSettingForPlatformPlugin (debugger, PlatformLinuxProperties::GetSettingName()))
125     {
126         const bool is_global_setting = true;
127         PluginManager::CreateSettingForPlatformPlugin (debugger,
128                                                        GetGlobalProperties()->GetValueProperties(),
129                                                        ConstString ("Properties for the PlatformLinux plug-in."),
130                                                        is_global_setting);
131     }
132 }
133 
134 
135 //------------------------------------------------------------------
136 
137 PlatformSP
138 PlatformLinux::CreateInstance (bool force, const ArchSpec *arch)
139 {
140     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PLATFORM));
141     if (log)
142     {
143         const char *arch_name;
144         if (arch && arch->GetArchitectureName ())
145             arch_name = arch->GetArchitectureName ();
146         else
147             arch_name = "<null>";
148 
149         const char *triple_cstr = arch ? arch->GetTriple ().getTriple ().c_str() : "<null>";
150 
151         log->Printf ("PlatformLinux::%s(force=%s, arch={%s,%s})", __FUNCTION__, force ? "true" : "false", arch_name, triple_cstr);
152     }
153 
154     bool create = force;
155     if (create == false && arch && arch->IsValid())
156     {
157         const llvm::Triple &triple = arch->GetTriple();
158         switch (triple.getVendor())
159         {
160             case llvm::Triple::PC:
161                 create = true;
162                 break;
163 
164 #if defined(__linux__)
165             // Only accept "unknown" for the vendor if the host is linux and
166             // it "unknown" wasn't specified (it was just returned because it
167             // was NOT specified_
168             case llvm::Triple::VendorType::UnknownVendor:
169                 create = !arch->TripleVendorWasSpecified();
170                 break;
171 #endif
172             default:
173                 break;
174         }
175 
176         if (create)
177         {
178             switch (triple.getOS())
179             {
180                 case llvm::Triple::Linux:
181                     break;
182 
183 #if defined(__linux__)
184                 // Only accept "unknown" for the OS if the host is linux and
185                 // it "unknown" wasn't specified (it was just returned because it
186                 // was NOT specified)
187                 case llvm::Triple::OSType::UnknownOS:
188                     create = !arch->TripleOSWasSpecified();
189                     break;
190 #endif
191                 default:
192                     create = false;
193                     break;
194             }
195         }
196     }
197 
198     if (create)
199     {
200         if (log)
201             log->Printf ("PlatformLinux::%s() creating remote-linux platform", __FUNCTION__);
202         return PlatformSP(new PlatformLinux(false));
203     }
204 
205     if (log)
206         log->Printf ("PlatformLinux::%s() aborting creation of remote-linux platform", __FUNCTION__);
207 
208     return PlatformSP();
209 }
210 
211 
212 lldb_private::ConstString
213 PlatformLinux::GetPluginNameStatic (bool is_host)
214 {
215     if (is_host)
216     {
217         static ConstString g_host_name(Platform::GetHostPlatformName ());
218         return g_host_name;
219     }
220     else
221     {
222         static ConstString g_remote_name("remote-linux");
223         return g_remote_name;
224     }
225 }
226 
227 const char *
228 PlatformLinux::GetPluginDescriptionStatic (bool is_host)
229 {
230     if (is_host)
231         return "Local Linux user platform plug-in.";
232     else
233         return "Remote Linux user platform plug-in.";
234 }
235 
236 lldb_private::ConstString
237 PlatformLinux::GetPluginName()
238 {
239     return GetPluginNameStatic(IsHost());
240 }
241 
242 void
243 PlatformLinux::Initialize ()
244 {
245     if (g_initialize_count++ == 0)
246     {
247 #if defined(__linux__)
248         PlatformSP default_platform_sp (new PlatformLinux(true));
249         default_platform_sp->SetSystemArchitecture(HostInfo::GetArchitecture());
250         Platform::SetHostPlatform (default_platform_sp);
251 #endif
252         PluginManager::RegisterPlugin(PlatformLinux::GetPluginNameStatic(false),
253                                       PlatformLinux::GetPluginDescriptionStatic(false),
254                                       PlatformLinux::CreateInstance,
255                                       PlatformLinux::DebuggerInitialize);
256     }
257 }
258 
259 void
260 PlatformLinux::Terminate ()
261 {
262     if (g_initialize_count > 0)
263     {
264         if (--g_initialize_count == 0)
265         {
266             PluginManager::UnregisterPlugin (PlatformLinux::CreateInstance);
267         }
268     }
269 }
270 
271 Error
272 PlatformLinux::ResolveExecutable (const ModuleSpec &ms,
273                                   lldb::ModuleSP &exe_module_sp,
274                                   const FileSpecList *module_search_paths_ptr)
275 {
276     Error error;
277     // Nothing special to do here, just use the actual file and architecture
278 
279     char exe_path[PATH_MAX];
280     ModuleSpec resolved_module_spec (ms);
281 
282     if (IsHost())
283     {
284         // If we have "ls" as the exe_file, resolve the executable location based on
285         // the current path variables
286         if (!resolved_module_spec.GetFileSpec().Exists())
287         {
288             resolved_module_spec.GetFileSpec().GetPath(exe_path, sizeof(exe_path));
289             resolved_module_spec.GetFileSpec().SetFile(exe_path, true);
290         }
291 
292         if (!resolved_module_spec.GetFileSpec().Exists())
293             resolved_module_spec.GetFileSpec().ResolveExecutableLocation ();
294 
295         if (resolved_module_spec.GetFileSpec().Exists())
296             error.Clear();
297         else
298         {
299             error.SetErrorStringWithFormat("unable to find executable for '%s'", resolved_module_spec.GetFileSpec().GetPath().c_str());
300         }
301     }
302     else
303     {
304         if (m_remote_platform_sp)
305         {
306             error = m_remote_platform_sp->ResolveExecutable (ms,
307                                                              exe_module_sp,
308                                                              NULL);
309         }
310         else
311         {
312             // We may connect to a process and use the provided executable (Don't use local $PATH).
313 
314             if (resolved_module_spec.GetFileSpec().Exists())
315                 error.Clear();
316             else
317                 error.SetErrorStringWithFormat("the platform is not currently connected, and '%s' doesn't exist in the system root.", exe_path);
318         }
319     }
320 
321     if (error.Success())
322     {
323         if (resolved_module_spec.GetArchitecture().IsValid())
324         {
325             error = ModuleList::GetSharedModule (resolved_module_spec,
326                                                  exe_module_sp,
327                                                  NULL,
328                                                  NULL,
329                                                  NULL);
330             if (error.Fail())
331             {
332                 // If we failed, it may be because the vendor and os aren't known. If that is the
333                 // case, try setting them to the host architecture and give it another try.
334                 llvm::Triple &module_triple = resolved_module_spec.GetArchitecture().GetTriple();
335                 bool is_vendor_specified = (module_triple.getVendor() != llvm::Triple::UnknownVendor);
336                 bool is_os_specified = (module_triple.getOS() != llvm::Triple::UnknownOS);
337                 if (!is_vendor_specified || !is_os_specified)
338                 {
339                     const llvm::Triple &host_triple = HostInfo::GetArchitecture(HostInfo::eArchKindDefault).GetTriple();
340 
341                     if (!is_vendor_specified)
342                         module_triple.setVendorName (host_triple.getVendorName());
343                     if (!is_os_specified)
344                         module_triple.setOSName (host_triple.getOSName());
345 
346                     error = ModuleList::GetSharedModule (resolved_module_spec,
347                                                          exe_module_sp,
348                                                          NULL,
349                                                          NULL,
350                                                          NULL);
351                 }
352             }
353 
354             // TODO find out why exe_module_sp might be NULL
355             if (!exe_module_sp || exe_module_sp->GetObjectFile() == NULL)
356             {
357                 exe_module_sp.reset();
358                 error.SetErrorStringWithFormat ("'%s' doesn't contain the architecture %s",
359                                                 resolved_module_spec.GetFileSpec().GetPath().c_str(),
360                                                 resolved_module_spec.GetArchitecture().GetArchitectureName());
361             }
362         }
363         else
364         {
365             // No valid architecture was specified, ask the platform for
366             // the architectures that we should be using (in the correct order)
367             // and see if we can find a match that way
368             StreamString arch_names;
369             for (uint32_t idx = 0; GetSupportedArchitectureAtIndex (idx, resolved_module_spec.GetArchitecture()); ++idx)
370             {
371                 error = ModuleList::GetSharedModule (resolved_module_spec,
372                                                      exe_module_sp,
373                                                      NULL,
374                                                      NULL,
375                                                      NULL);
376                 // Did we find an executable using one of the
377                 if (error.Success())
378                 {
379                     if (exe_module_sp && exe_module_sp->GetObjectFile())
380                         break;
381                     else
382                         error.SetErrorToGenericError();
383                 }
384 
385                 if (idx > 0)
386                     arch_names.PutCString (", ");
387                 arch_names.PutCString (resolved_module_spec.GetArchitecture().GetArchitectureName());
388             }
389 
390             if (error.Fail() || !exe_module_sp)
391             {
392                 if (resolved_module_spec.GetFileSpec().Readable())
393                 {
394                     error.SetErrorStringWithFormat ("'%s' doesn't contain any '%s' platform architectures: %s",
395                                                     resolved_module_spec.GetFileSpec().GetPath().c_str(),
396                                                     GetPluginName().GetCString(),
397                                                     arch_names.GetString().c_str());
398                 }
399                 else
400                 {
401                     error.SetErrorStringWithFormat("'%s' is not readable", resolved_module_spec.GetFileSpec().GetPath().c_str());
402                 }
403             }
404         }
405     }
406 
407     return error;
408 }
409 
410 Error
411 PlatformLinux::GetFileWithUUID (const FileSpec &platform_file,
412                                 const UUID *uuid_ptr, FileSpec &local_file)
413 {
414     if (IsRemote())
415     {
416         if (m_remote_platform_sp)
417             return m_remote_platform_sp->GetFileWithUUID (platform_file, uuid_ptr, local_file);
418     }
419 
420     // Default to the local case
421     local_file = platform_file;
422     return Error();
423 }
424 
425 
426 //------------------------------------------------------------------
427 /// Default Constructor
428 //------------------------------------------------------------------
429 PlatformLinux::PlatformLinux (bool is_host) :
430     PlatformPOSIX(is_host)  // This is the local host platform
431 {
432 }
433 
434 //------------------------------------------------------------------
435 /// Destructor.
436 ///
437 /// The destructor is virtual since this class is designed to be
438 /// inherited from by the plug-in instance.
439 //------------------------------------------------------------------
440 PlatformLinux::~PlatformLinux()
441 {
442 }
443 
444 bool
445 PlatformLinux::GetProcessInfo (lldb::pid_t pid, ProcessInstanceInfo &process_info)
446 {
447     bool success = false;
448     if (IsHost())
449     {
450         success = Platform::GetProcessInfo (pid, process_info);
451     }
452     else
453     {
454         if (m_remote_platform_sp)
455             success = m_remote_platform_sp->GetProcessInfo (pid, process_info);
456     }
457     return success;
458 }
459 
460 uint32_t
461 PlatformLinux::FindProcesses (const ProcessInstanceInfoMatch &match_info,
462                               ProcessInstanceInfoList &process_infos)
463 {
464     uint32_t match_count = 0;
465     if (IsHost())
466     {
467         // Let the base class figure out the host details
468         match_count = Platform::FindProcesses (match_info, process_infos);
469     }
470     else
471     {
472         // If we are remote, we can only return results if we are connected
473         if (m_remote_platform_sp)
474             match_count = m_remote_platform_sp->FindProcesses (match_info, process_infos);
475     }
476     return match_count;
477 }
478 
479 bool
480 PlatformLinux::GetSupportedArchitectureAtIndex (uint32_t idx, ArchSpec &arch)
481 {
482     if (idx == 0)
483     {
484         arch = HostInfo::GetArchitecture(HostInfo::eArchKindDefault);
485         return arch.IsValid();
486     }
487     else if (idx == 1)
488     {
489         // If the default host architecture is 64-bit, look for a 32-bit variant
490         ArchSpec hostArch = HostInfo::GetArchitecture(HostInfo::eArchKindDefault);
491         if (hostArch.IsValid() && hostArch.GetTriple().isArch64Bit())
492         {
493             arch = HostInfo::GetArchitecture(HostInfo::eArchKind32);
494             return arch.IsValid();
495         }
496     }
497     return false;
498 }
499 
500 void
501 PlatformLinux::GetStatus (Stream &strm)
502 {
503     Platform::GetStatus(strm);
504 
505 #ifndef LLDB_DISABLE_POSIX
506     struct utsname un;
507 
508     if (uname(&un))
509         return;
510 
511     strm.Printf ("    Kernel: %s\n", un.sysname);
512     strm.Printf ("   Release: %s\n", un.release);
513     strm.Printf ("   Version: %s\n", un.version);
514 #endif
515 }
516 
517 size_t
518 PlatformLinux::GetSoftwareBreakpointTrapOpcode (Target &target,
519                                                 BreakpointSite *bp_site)
520 {
521     ArchSpec arch = target.GetArchitecture();
522     const uint8_t *trap_opcode = NULL;
523     size_t trap_opcode_size = 0;
524 
525     switch (arch.GetMachine())
526     {
527     default:
528         assert(false && "CPU type not supported!");
529         break;
530 
531     case llvm::Triple::aarch64:
532         {
533             static const uint8_t g_aarch64_opcode[] = { 0x00, 0x00, 0x20, 0xd4 };
534             trap_opcode = g_aarch64_opcode;
535             trap_opcode_size = sizeof(g_aarch64_opcode);
536         }
537         break;
538     case llvm::Triple::x86:
539     case llvm::Triple::x86_64:
540         {
541             static const uint8_t g_i386_breakpoint_opcode[] = { 0xCC };
542             trap_opcode = g_i386_breakpoint_opcode;
543             trap_opcode_size = sizeof(g_i386_breakpoint_opcode);
544         }
545         break;
546     case llvm::Triple::hexagon:
547         {
548             static const uint8_t g_hex_opcode[] = { 0x0c, 0xdb, 0x00, 0x54 };
549             trap_opcode = g_hex_opcode;
550             trap_opcode_size = sizeof(g_hex_opcode);
551         }
552         break;
553     case llvm::Triple::arm:
554         {
555             // The ARM reference recommends the use of 0xe7fddefe and 0xdefe
556             // but the linux kernel does otherwise.
557             static const uint8_t g_arm_breakpoint_opcode[] = { 0xf0, 0x01, 0xf0, 0xe7 };
558             static const uint8_t g_thumb_breakpoint_opcode[] = { 0x01, 0xde };
559 
560             lldb::BreakpointLocationSP bp_loc_sp (bp_site->GetOwnerAtIndex (0));
561             AddressClass addr_class = eAddressClassUnknown;
562 
563             if (bp_loc_sp)
564                 addr_class = bp_loc_sp->GetAddress ().GetAddressClass ();
565 
566             if (addr_class == eAddressClassCodeAlternateISA
567                 || (addr_class == eAddressClassUnknown
568                     && bp_loc_sp->GetAddress().GetOffset() & 1))
569             {
570                 trap_opcode = g_thumb_breakpoint_opcode;
571                 trap_opcode_size = sizeof(g_thumb_breakpoint_opcode);
572             }
573             else
574             {
575                 trap_opcode = g_arm_breakpoint_opcode;
576                 trap_opcode_size = sizeof(g_arm_breakpoint_opcode);
577             }
578         }
579         break;
580     }
581 
582     if (bp_site->SetTrapOpcode(trap_opcode, trap_opcode_size))
583         return trap_opcode_size;
584     return 0;
585 }
586 
587 int32_t
588 PlatformLinux::GetResumeCountForLaunchInfo (ProcessLaunchInfo &launch_info)
589 {
590     int32_t resume_count = 0;
591 
592     // Always resume past the initial stop when we use eLaunchFlagDebug
593     if (launch_info.GetFlags ().Test (eLaunchFlagDebug))
594     {
595         // Resume past the stop for the final exec into the true inferior.
596         ++resume_count;
597     }
598 
599     // If we're not launching a shell, we're done.
600     const FileSpec &shell = launch_info.GetShell();
601     if (!shell)
602         return resume_count;
603 
604     std::string shell_string = shell.GetPath();
605     // We're in a shell, so for sure we have to resume past the shell exec.
606     ++resume_count;
607 
608     // Figure out what shell we're planning on using.
609     const char *shell_name = strrchr (shell_string.c_str(), '/');
610     if (shell_name == NULL)
611         shell_name = shell_string.c_str();
612     else
613         shell_name++;
614 
615     if (strcmp (shell_name, "csh") == 0
616              || strcmp (shell_name, "tcsh") == 0
617              || strcmp (shell_name, "zsh") == 0
618              || strcmp (shell_name, "sh") == 0)
619     {
620         // These shells seem to re-exec themselves.  Add another resume.
621         ++resume_count;
622     }
623 
624     return resume_count;
625 }
626 
627 bool
628 PlatformLinux::UseLlgsForLocalDebugging ()
629 {
630     PlatformLinuxPropertiesSP properties_sp = GetGlobalProperties ();
631     assert (properties_sp && "global properties shared pointer is null");
632     return properties_sp ? properties_sp->GetUseLlgsForLocal () : false;
633 }
634 
635 bool
636 PlatformLinux::CanDebugProcess ()
637 {
638     if (IsHost ())
639     {
640         // The platform only does local debugging (i.e. uses llgs) when the setting indicates we do that.
641         // Otherwise, we'll use ProcessLinux/ProcessPOSIX to handle with ProcessMonitor.
642         return UseLlgsForLocalDebugging ();
643     }
644     else
645     {
646         // If we're connected, we can debug.
647         return IsConnected ();
648     }
649 }
650 
651 // For local debugging, Linux will override the debug logic to use llgs-launch rather than
652 // lldb-launch, llgs-attach.  This differs from current lldb-launch, debugserver-attach
653 // approach on MacOSX.
654 lldb::ProcessSP
655 PlatformLinux::DebugProcess (ProcessLaunchInfo &launch_info,
656                              Debugger &debugger,
657                              Target *target,       // Can be NULL, if NULL create a new target, else use existing one
658                              Error &error)
659 {
660     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PLATFORM));
661     if (log)
662         log->Printf ("PlatformLinux::%s entered (target %p)", __FUNCTION__, static_cast<void*>(target));
663 
664     // If we're a remote host, use standard behavior from parent class.
665     if (!IsHost ())
666         return PlatformPOSIX::DebugProcess (launch_info, debugger, target, error);
667 
668     //
669     // For local debugging, we'll insist on having ProcessGDBRemote create the process.
670     //
671 
672     ProcessSP process_sp;
673 
674     // Ensure we're using llgs for local debugging.
675     if (!UseLlgsForLocalDebugging ())
676     {
677         assert (false && "we're trying to debug a local process but platform.plugin.linux.use-llgs-for-local is false, should never get here");
678         error.SetErrorString ("attempted to start gdb-remote-based debugging for local process but platform.plugin.linux.use-llgs-for-local is false");
679         return process_sp;
680     }
681 
682     // Make sure we stop at the entry point
683     launch_info.GetFlags ().Set (eLaunchFlagDebug);
684 
685     // We always launch the process we are going to debug in a separate process
686     // group, since then we can handle ^C interrupts ourselves w/o having to worry
687     // about the target getting them as well.
688     launch_info.SetLaunchInSeparateProcessGroup(true);
689 
690     // Ensure we have a target.
691     if (target == nullptr)
692     {
693         if (log)
694             log->Printf ("PlatformLinux::%s creating new target", __FUNCTION__);
695 
696         TargetSP new_target_sp;
697         error = debugger.GetTargetList().CreateTarget (debugger,
698                                                        nullptr,
699                                                        nullptr,
700                                                        false,
701                                                        nullptr,
702                                                        new_target_sp);
703         if (error.Fail ())
704         {
705             if (log)
706                 log->Printf ("PlatformLinux::%s failed to create new target: %s", __FUNCTION__, error.AsCString ());
707             return process_sp;
708         }
709 
710         target = new_target_sp.get();
711         if (!target)
712         {
713             error.SetErrorString ("CreateTarget() returned nullptr");
714             if (log)
715                 log->Printf ("PlatformLinux::%s failed: %s", __FUNCTION__, error.AsCString ());
716             return process_sp;
717         }
718     }
719     else
720     {
721         if (log)
722             log->Printf ("PlatformLinux::%s using provided target", __FUNCTION__);
723     }
724 
725     // Mark target as currently selected target.
726     debugger.GetTargetList().SetSelectedTarget(target);
727 
728     // Now create the gdb-remote process.
729     if (log)
730         log->Printf ("PlatformLinux::%s having target create process with gdb-remote plugin", __FUNCTION__);
731     process_sp = target->CreateProcess (launch_info.GetListenerForProcess(debugger), "gdb-remote", nullptr);
732 
733     if (!process_sp)
734     {
735         error.SetErrorString ("CreateProcess() failed for gdb-remote process");
736         if (log)
737             log->Printf ("PlatformLinux::%s failed: %s", __FUNCTION__, error.AsCString ());
738         return process_sp;
739     }
740     else
741     {
742         if (log)
743             log->Printf ("PlatformLinux::%s successfully created process", __FUNCTION__);
744     }
745 
746     // Set the unix signals properly.
747     process_sp->SetUnixSignals (Host::GetUnixSignals ());
748 
749     // Adjust launch for a hijacker.
750     ListenerSP listener_sp;
751     if (!launch_info.GetHijackListener ())
752     {
753         if (log)
754             log->Printf ("PlatformLinux::%s setting up hijacker", __FUNCTION__);
755 
756         listener_sp.reset (new Listener("lldb.PlatformLinux.DebugProcess.hijack"));
757         launch_info.SetHijackListener (listener_sp);
758         process_sp->HijackProcessEvents (listener_sp.get ());
759     }
760 
761     // Log file actions.
762     if (log)
763     {
764         log->Printf ("PlatformLinux::%s launching process with the following file actions:", __FUNCTION__);
765 
766         StreamString stream;
767         size_t i = 0;
768         const FileAction *file_action;
769         while ((file_action = launch_info.GetFileActionAtIndex (i++)) != nullptr)
770         {
771             file_action->Dump (stream);
772             log->PutCString (stream.GetString().c_str ());
773             stream.Clear();
774         }
775     }
776 
777     // Do the launch.
778     error = process_sp->Launch(launch_info);
779     if (error.Success ())
780     {
781         // Handle the hijacking of process events.
782         if (listener_sp)
783         {
784             const StateType state = process_sp->WaitForProcessToStop (NULL, NULL, false, listener_sp.get());
785             process_sp->RestoreProcessEvents();
786 
787             if (state == eStateStopped)
788             {
789                 if (log)
790                     log->Printf ("PlatformLinux::%s pid %" PRIu64 " state %s\n",
791                                  __FUNCTION__, process_sp->GetID (), StateAsCString (state));
792             }
793             else
794             {
795                 if (log)
796                     log->Printf ("PlatformLinux::%s pid %" PRIu64 " state is not stopped - %s\n",
797                                  __FUNCTION__, process_sp->GetID (), StateAsCString (state));
798             }
799         }
800 
801         // Hook up process PTY if we have one (which we should for local debugging with llgs).
802         int pty_fd = launch_info.GetPTY().ReleaseMasterFileDescriptor();
803         if (pty_fd != lldb_utility::PseudoTerminal::invalid_fd)
804         {
805             process_sp->SetSTDIOFileDescriptor(pty_fd);
806             if (log)
807                 log->Printf ("PlatformLinux::%s pid %" PRIu64 " hooked up STDIO pty to process", __FUNCTION__, process_sp->GetID ());
808         }
809         else
810         {
811             if (log)
812                 log->Printf ("PlatformLinux::%s pid %" PRIu64 " not using process STDIO pty", __FUNCTION__, process_sp->GetID ());
813         }
814     }
815     else
816     {
817         if (log)
818             log->Printf ("PlatformLinux::%s process launch failed: %s", __FUNCTION__, error.AsCString ());
819         // FIXME figure out appropriate cleanup here.  Do we delete the target? Do we delete the process?  Does our caller do that?
820     }
821 
822     return process_sp;
823 }
824 
825 void
826 PlatformLinux::CalculateTrapHandlerSymbolNames ()
827 {
828     m_trap_handlers.push_back (ConstString ("_sigtramp"));
829 }
830 
831 Error
832 PlatformLinux::LaunchNativeProcess (
833     ProcessLaunchInfo &launch_info,
834     lldb_private::NativeProcessProtocol::NativeDelegate &native_delegate,
835     NativeProcessProtocolSP &process_sp)
836 {
837 #if !defined(__linux__) || defined(__ANDROID_NDK__)
838     return Error("only implemented on Linux hosts");
839 #else
840     if (!IsHost ())
841         return Error("PlatformLinux::%s (): cannot launch a debug process when not the host", __FUNCTION__);
842 
843     // Retrieve the exe module.
844     lldb::ModuleSP exe_module_sp;
845     ModuleSpec exe_module_spec(launch_info.GetExecutableFile(), launch_info.GetArchitecture());
846 
847     Error error = ResolveExecutable (
848         exe_module_spec,
849         exe_module_sp,
850         NULL);
851 
852     if (!error.Success ())
853         return error;
854 
855     if (!exe_module_sp)
856         return Error("exe_module_sp could not be resolved for %s", launch_info.GetExecutableFile ().GetPath ().c_str ());
857 
858     // Launch it for debugging
859     error = NativeProcessLinux::LaunchProcess (
860         exe_module_sp.get (),
861         launch_info,
862         native_delegate,
863         process_sp);
864 
865     return error;
866 #endif
867 }
868 
869 Error
870 PlatformLinux::AttachNativeProcess (lldb::pid_t pid,
871                                     lldb_private::NativeProcessProtocol::NativeDelegate &native_delegate,
872                                     NativeProcessProtocolSP &process_sp)
873 {
874 #if !defined(__linux__) || defined(__ANDROID_NDK__)
875     return Error("only implemented on Linux hosts");
876 #else
877     if (!IsHost ())
878         return Error("PlatformLinux::%s (): cannot attach to a debug process when not the host", __FUNCTION__);
879 
880     // Launch it for debugging
881     return NativeProcessLinux::AttachToProcess (pid, native_delegate, process_sp);
882 #endif
883 }
884