1 //===-- PlatformDarwin.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 "PlatformDarwin.h"
10 
11 #include <cstring>
12 
13 #include <algorithm>
14 #include <memory>
15 #include <mutex>
16 
17 #include "lldb/Breakpoint/BreakpointLocation.h"
18 #include "lldb/Breakpoint/BreakpointSite.h"
19 #include "lldb/Core/Debugger.h"
20 #include "lldb/Core/Module.h"
21 #include "lldb/Core/ModuleSpec.h"
22 #include "lldb/Core/Section.h"
23 #include "lldb/Host/Host.h"
24 #include "lldb/Host/HostInfo.h"
25 #include "lldb/Host/XML.h"
26 #include "lldb/Interpreter/CommandInterpreter.h"
27 #include "lldb/Symbol/LocateSymbolFile.h"
28 #include "lldb/Symbol/ObjectFile.h"
29 #include "lldb/Symbol/SymbolFile.h"
30 #include "lldb/Symbol/SymbolVendor.h"
31 #include "lldb/Target/Platform.h"
32 #include "lldb/Target/Process.h"
33 #include "lldb/Target/Target.h"
34 #include "lldb/Utility/Log.h"
35 #include "lldb/Utility/ProcessInfo.h"
36 #include "lldb/Utility/Status.h"
37 #include "lldb/Utility/Timer.h"
38 #include "llvm/ADT/STLExtras.h"
39 #include "llvm/Support/FileSystem.h"
40 #include "llvm/Support/Threading.h"
41 #include "llvm/Support/VersionTuple.h"
42 
43 #if defined(__APPLE__)
44 #include <TargetConditionals.h>
45 #endif
46 
47 using namespace lldb;
48 using namespace lldb_private;
49 
50 /// Default Constructor
51 PlatformDarwin::PlatformDarwin(bool is_host) : PlatformPOSIX(is_host) {}
52 
53 /// Destructor.
54 ///
55 /// The destructor is virtual since this class is designed to be
56 /// inherited from by the plug-in instance.
57 PlatformDarwin::~PlatformDarwin() = default;
58 
59 lldb_private::Status
60 PlatformDarwin::PutFile(const lldb_private::FileSpec &source,
61                         const lldb_private::FileSpec &destination, uint32_t uid,
62                         uint32_t gid) {
63   // Unconditionally unlink the destination. If it is an executable,
64   // simply opening it and truncating its contents would invalidate
65   // its cached code signature.
66   Unlink(destination);
67   return PlatformPOSIX::PutFile(source, destination, uid, gid);
68 }
69 
70 FileSpecList PlatformDarwin::LocateExecutableScriptingResources(
71     Target *target, Module &module, Stream *feedback_stream) {
72   FileSpecList file_list;
73   if (target &&
74       target->GetDebugger().GetScriptLanguage() == eScriptLanguagePython) {
75     // NB some extensions might be meaningful and should not be stripped -
76     // "this.binary.file"
77     // should not lose ".file" but GetFileNameStrippingExtension() will do
78     // precisely that. Ideally, we should have a per-platform list of
79     // extensions (".exe", ".app", ".dSYM", ".framework") which should be
80     // stripped while leaving "this.binary.file" as-is.
81 
82     FileSpec module_spec = module.GetFileSpec();
83 
84     if (module_spec) {
85       if (SymbolFile *symfile = module.GetSymbolFile()) {
86         ObjectFile *objfile = symfile->GetObjectFile();
87         if (objfile) {
88           FileSpec symfile_spec(objfile->GetFileSpec());
89           if (symfile_spec &&
90               strcasestr(symfile_spec.GetPath().c_str(),
91                          ".dSYM/Contents/Resources/DWARF") != nullptr &&
92               FileSystem::Instance().Exists(symfile_spec)) {
93             while (module_spec.GetFilename()) {
94               std::string module_basename(
95                   module_spec.GetFilename().GetCString());
96               std::string original_module_basename(module_basename);
97 
98               bool was_keyword = false;
99 
100               // FIXME: for Python, we cannot allow certain characters in
101               // module
102               // filenames we import. Theoretically, different scripting
103               // languages may have different sets of forbidden tokens in
104               // filenames, and that should be dealt with by each
105               // ScriptInterpreter. For now, we just replace dots with
106               // underscores, but if we ever support anything other than
107               // Python we will need to rework this
108               std::replace(module_basename.begin(), module_basename.end(), '.',
109                            '_');
110               std::replace(module_basename.begin(), module_basename.end(), ' ',
111                            '_');
112               std::replace(module_basename.begin(), module_basename.end(), '-',
113                            '_');
114               ScriptInterpreter *script_interpreter =
115                   target->GetDebugger().GetScriptInterpreter();
116               if (script_interpreter &&
117                   script_interpreter->IsReservedWord(module_basename.c_str())) {
118                 module_basename.insert(module_basename.begin(), '_');
119                 was_keyword = true;
120               }
121 
122               StreamString path_string;
123               StreamString original_path_string;
124               // for OSX we are going to be in
125               // .dSYM/Contents/Resources/DWARF/<basename> let us go to
126               // .dSYM/Contents/Resources/Python/<basename>.py and see if the
127               // file exists
128               path_string.Printf("%s/../Python/%s.py",
129                                  symfile_spec.GetDirectory().GetCString(),
130                                  module_basename.c_str());
131               original_path_string.Printf(
132                   "%s/../Python/%s.py",
133                   symfile_spec.GetDirectory().GetCString(),
134                   original_module_basename.c_str());
135               FileSpec script_fspec(path_string.GetString());
136               FileSystem::Instance().Resolve(script_fspec);
137               FileSpec orig_script_fspec(original_path_string.GetString());
138               FileSystem::Instance().Resolve(orig_script_fspec);
139 
140               // if we did some replacements of reserved characters, and a
141               // file with the untampered name exists, then warn the user
142               // that the file as-is shall not be loaded
143               if (feedback_stream) {
144                 if (module_basename != original_module_basename &&
145                     FileSystem::Instance().Exists(orig_script_fspec)) {
146                   const char *reason_for_complaint =
147                       was_keyword ? "conflicts with a keyword"
148                                   : "contains reserved characters";
149                   if (FileSystem::Instance().Exists(script_fspec))
150                     feedback_stream->Printf(
151                         "warning: the symbol file '%s' contains a debug "
152                         "script. However, its name"
153                         " '%s' %s and as such cannot be loaded. LLDB will"
154                         " load '%s' instead. Consider removing the file with "
155                         "the malformed name to"
156                         " eliminate this warning.\n",
157                         symfile_spec.GetPath().c_str(),
158                         original_path_string.GetData(), reason_for_complaint,
159                         path_string.GetData());
160                   else
161                     feedback_stream->Printf(
162                         "warning: the symbol file '%s' contains a debug "
163                         "script. However, its name"
164                         " %s and as such cannot be loaded. If you intend"
165                         " to have this script loaded, please rename '%s' to "
166                         "'%s' and retry.\n",
167                         symfile_spec.GetPath().c_str(), reason_for_complaint,
168                         original_path_string.GetData(), path_string.GetData());
169                 }
170               }
171 
172               if (FileSystem::Instance().Exists(script_fspec)) {
173                 file_list.Append(script_fspec);
174                 break;
175               }
176 
177               // If we didn't find the python file, then keep stripping the
178               // extensions and try again
179               ConstString filename_no_extension(
180                   module_spec.GetFileNameStrippingExtension());
181               if (module_spec.GetFilename() == filename_no_extension)
182                 break;
183 
184               module_spec.GetFilename() = filename_no_extension;
185             }
186           }
187         }
188       }
189     }
190   }
191   return file_list;
192 }
193 
194 Status PlatformDarwin::ResolveSymbolFile(Target &target,
195                                          const ModuleSpec &sym_spec,
196                                          FileSpec &sym_file) {
197   sym_file = sym_spec.GetSymbolFileSpec();
198   if (FileSystem::Instance().IsDirectory(sym_file)) {
199     sym_file = Symbols::FindSymbolFileInBundle(sym_file, sym_spec.GetUUIDPtr(),
200                                                sym_spec.GetArchitecturePtr());
201   }
202   return {};
203 }
204 
205 static lldb_private::Status
206 MakeCacheFolderForFile(const FileSpec &module_cache_spec) {
207   FileSpec module_cache_folder =
208       module_cache_spec.CopyByRemovingLastPathComponent();
209   return llvm::sys::fs::create_directory(module_cache_folder.GetPath());
210 }
211 
212 static lldb_private::Status
213 BringInRemoteFile(Platform *platform,
214                   const lldb_private::ModuleSpec &module_spec,
215                   const FileSpec &module_cache_spec) {
216   MakeCacheFolderForFile(module_cache_spec);
217   Status err = platform->GetFile(module_spec.GetFileSpec(), module_cache_spec);
218   return err;
219 }
220 
221 lldb_private::Status PlatformDarwin::GetSharedModuleWithLocalCache(
222     const lldb_private::ModuleSpec &module_spec, lldb::ModuleSP &module_sp,
223     const lldb_private::FileSpecList *module_search_paths_ptr,
224     llvm::SmallVectorImpl<lldb::ModuleSP> *old_modules, bool *did_create_ptr) {
225 
226   Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));
227   LLDB_LOGF(log,
228             "[%s] Trying to find module %s/%s - platform path %s/%s symbol "
229             "path %s/%s",
230             (IsHost() ? "host" : "remote"),
231             module_spec.GetFileSpec().GetDirectory().AsCString(),
232             module_spec.GetFileSpec().GetFilename().AsCString(),
233             module_spec.GetPlatformFileSpec().GetDirectory().AsCString(),
234             module_spec.GetPlatformFileSpec().GetFilename().AsCString(),
235             module_spec.GetSymbolFileSpec().GetDirectory().AsCString(),
236             module_spec.GetSymbolFileSpec().GetFilename().AsCString());
237 
238   Status err;
239 
240   if (IsHost()) {
241     // When debugging on the host, we are most likely using the same shared
242     // cache as our inferior. The dylibs from the shared cache might not
243     // exist on the filesystem, so let's use the images in our own memory
244     // to create the modules.
245 
246     // Check if the requested image is in our shared cache.
247     SharedCacheImageInfo image_info =
248         HostInfo::GetSharedCacheImageInfo(module_spec.GetFileSpec().GetPath());
249 
250     // If we found it and it has the correct UUID, let's proceed with
251     // creating a module from the memory contents.
252     if (image_info.uuid &&
253         (!module_spec.GetUUID() || module_spec.GetUUID() == image_info.uuid)) {
254       ModuleSpec shared_cache_spec(module_spec.GetFileSpec(), image_info.uuid,
255                                    image_info.data_sp);
256       err = ModuleList::GetSharedModule(shared_cache_spec, module_sp,
257                                         module_search_paths_ptr, old_modules,
258                                         did_create_ptr);
259       if (module_sp)
260         return err;
261     }
262   }
263 
264   err = ModuleList::GetSharedModule(module_spec, module_sp,
265                                     module_search_paths_ptr, old_modules,
266                                     did_create_ptr);
267   if (module_sp)
268     return err;
269 
270   if (!IsHost()) {
271     std::string cache_path(GetLocalCacheDirectory());
272     // Only search for a locally cached file if we have a valid cache path
273     if (!cache_path.empty()) {
274       std::string module_path(module_spec.GetFileSpec().GetPath());
275       cache_path.append(module_path);
276       FileSpec module_cache_spec(cache_path);
277 
278       // if rsync is supported, always bring in the file - rsync will be very
279       // efficient when files are the same on the local and remote end of the
280       // connection
281       if (this->GetSupportsRSync()) {
282         err = BringInRemoteFile(this, module_spec, module_cache_spec);
283         if (err.Fail())
284           return err;
285         if (FileSystem::Instance().Exists(module_cache_spec)) {
286           Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));
287           LLDB_LOGF(log, "[%s] module %s/%s was rsynced and is now there",
288                     (IsHost() ? "host" : "remote"),
289                     module_spec.GetFileSpec().GetDirectory().AsCString(),
290                     module_spec.GetFileSpec().GetFilename().AsCString());
291           ModuleSpec local_spec(module_cache_spec,
292                                 module_spec.GetArchitecture());
293           module_sp = std::make_shared<Module>(local_spec);
294           module_sp->SetPlatformFileSpec(module_spec.GetFileSpec());
295           return Status();
296         }
297       }
298 
299       // try to find the module in the cache
300       if (FileSystem::Instance().Exists(module_cache_spec)) {
301         // get the local and remote MD5 and compare
302         if (m_remote_platform_sp) {
303           // when going over the *slow* GDB remote transfer mechanism we first
304           // check the hashes of the files - and only do the actual transfer if
305           // they differ
306           uint64_t high_local, high_remote, low_local, low_remote;
307           auto MD5 = llvm::sys::fs::md5_contents(module_cache_spec.GetPath());
308           if (!MD5)
309             return Status(MD5.getError());
310           std::tie(high_local, low_local) = MD5->words();
311 
312           m_remote_platform_sp->CalculateMD5(module_spec.GetFileSpec(),
313                                              low_remote, high_remote);
314           if (low_local != low_remote || high_local != high_remote) {
315             // bring in the remote file
316             Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));
317             LLDB_LOGF(log,
318                       "[%s] module %s/%s needs to be replaced from remote copy",
319                       (IsHost() ? "host" : "remote"),
320                       module_spec.GetFileSpec().GetDirectory().AsCString(),
321                       module_spec.GetFileSpec().GetFilename().AsCString());
322             Status err =
323                 BringInRemoteFile(this, module_spec, module_cache_spec);
324             if (err.Fail())
325               return err;
326           }
327         }
328 
329         ModuleSpec local_spec(module_cache_spec, module_spec.GetArchitecture());
330         module_sp = std::make_shared<Module>(local_spec);
331         module_sp->SetPlatformFileSpec(module_spec.GetFileSpec());
332         Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));
333         LLDB_LOGF(log, "[%s] module %s/%s was found in the cache",
334                   (IsHost() ? "host" : "remote"),
335                   module_spec.GetFileSpec().GetDirectory().AsCString(),
336                   module_spec.GetFileSpec().GetFilename().AsCString());
337         return Status();
338       }
339 
340       // bring in the remote module file
341       LLDB_LOGF(log, "[%s] module %s/%s needs to come in remotely",
342                 (IsHost() ? "host" : "remote"),
343                 module_spec.GetFileSpec().GetDirectory().AsCString(),
344                 module_spec.GetFileSpec().GetFilename().AsCString());
345       Status err = BringInRemoteFile(this, module_spec, module_cache_spec);
346       if (err.Fail())
347         return err;
348       if (FileSystem::Instance().Exists(module_cache_spec)) {
349         Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));
350         LLDB_LOGF(log, "[%s] module %s/%s is now cached and fine",
351                   (IsHost() ? "host" : "remote"),
352                   module_spec.GetFileSpec().GetDirectory().AsCString(),
353                   module_spec.GetFileSpec().GetFilename().AsCString());
354         ModuleSpec local_spec(module_cache_spec, module_spec.GetArchitecture());
355         module_sp = std::make_shared<Module>(local_spec);
356         module_sp->SetPlatformFileSpec(module_spec.GetFileSpec());
357         return Status();
358       } else
359         return Status("unable to obtain valid module file");
360     } else
361       return Status("no cache path");
362   } else
363     return Status("unable to resolve module");
364 }
365 
366 Status PlatformDarwin::GetSharedModule(
367     const ModuleSpec &module_spec, Process *process, ModuleSP &module_sp,
368     const FileSpecList *module_search_paths_ptr,
369     llvm::SmallVectorImpl<ModuleSP> *old_modules, bool *did_create_ptr) {
370   Status error;
371   module_sp.reset();
372 
373   if (IsRemote()) {
374     // If we have a remote platform always, let it try and locate the shared
375     // module first.
376     if (m_remote_platform_sp) {
377       error = m_remote_platform_sp->GetSharedModule(
378           module_spec, process, module_sp, module_search_paths_ptr, old_modules,
379           did_create_ptr);
380     }
381   }
382 
383   if (!module_sp) {
384     // Fall back to the local platform and find the file locally
385     error = Platform::GetSharedModule(module_spec, process, module_sp,
386                                       module_search_paths_ptr, old_modules,
387                                       did_create_ptr);
388 
389     const FileSpec &platform_file = module_spec.GetFileSpec();
390     if (!module_sp && module_search_paths_ptr && platform_file) {
391       // We can try to pull off part of the file path up to the bundle
392       // directory level and try any module search paths...
393       FileSpec bundle_directory;
394       if (Host::GetBundleDirectory(platform_file, bundle_directory)) {
395         if (platform_file == bundle_directory) {
396           ModuleSpec new_module_spec(module_spec);
397           new_module_spec.GetFileSpec() = bundle_directory;
398           if (Host::ResolveExecutableInBundle(new_module_spec.GetFileSpec())) {
399             Status new_error(Platform::GetSharedModule(
400                 new_module_spec, process, module_sp, nullptr, old_modules,
401                 did_create_ptr));
402 
403             if (module_sp)
404               return new_error;
405           }
406         } else {
407           char platform_path[PATH_MAX];
408           char bundle_dir[PATH_MAX];
409           platform_file.GetPath(platform_path, sizeof(platform_path));
410           const size_t bundle_directory_len =
411               bundle_directory.GetPath(bundle_dir, sizeof(bundle_dir));
412           char new_path[PATH_MAX];
413           size_t num_module_search_paths = module_search_paths_ptr->GetSize();
414           for (size_t i = 0; i < num_module_search_paths; ++i) {
415             const size_t search_path_len =
416                 module_search_paths_ptr->GetFileSpecAtIndex(i).GetPath(
417                     new_path, sizeof(new_path));
418             if (search_path_len < sizeof(new_path)) {
419               snprintf(new_path + search_path_len,
420                        sizeof(new_path) - search_path_len, "/%s",
421                        platform_path + bundle_directory_len);
422               FileSpec new_file_spec(new_path);
423               if (FileSystem::Instance().Exists(new_file_spec)) {
424                 ModuleSpec new_module_spec(module_spec);
425                 new_module_spec.GetFileSpec() = new_file_spec;
426                 Status new_error(Platform::GetSharedModule(
427                     new_module_spec, process, module_sp, nullptr, old_modules,
428                     did_create_ptr));
429 
430                 if (module_sp) {
431                   module_sp->SetPlatformFileSpec(new_file_spec);
432                   return new_error;
433                 }
434               }
435             }
436           }
437         }
438       }
439     }
440   }
441   if (module_sp)
442     module_sp->SetPlatformFileSpec(module_spec.GetFileSpec());
443   return error;
444 }
445 
446 size_t
447 PlatformDarwin::GetSoftwareBreakpointTrapOpcode(Target &target,
448                                                 BreakpointSite *bp_site) {
449   const uint8_t *trap_opcode = nullptr;
450   uint32_t trap_opcode_size = 0;
451   bool bp_is_thumb = false;
452 
453   llvm::Triple::ArchType machine = target.GetArchitecture().GetMachine();
454   switch (machine) {
455   case llvm::Triple::aarch64_32:
456   case llvm::Triple::aarch64: {
457     // 'brk #0' or 0xd4200000 in BE byte order
458     static const uint8_t g_arm64_breakpoint_opcode[] = {0x00, 0x00, 0x20, 0xD4};
459     trap_opcode = g_arm64_breakpoint_opcode;
460     trap_opcode_size = sizeof(g_arm64_breakpoint_opcode);
461   } break;
462 
463   case llvm::Triple::thumb:
464     bp_is_thumb = true;
465     LLVM_FALLTHROUGH;
466   case llvm::Triple::arm: {
467     static const uint8_t g_arm_breakpoint_opcode[] = {0xFE, 0xDE, 0xFF, 0xE7};
468     static const uint8_t g_thumb_breakpooint_opcode[] = {0xFE, 0xDE};
469 
470     // Auto detect arm/thumb if it wasn't explicitly specified
471     if (!bp_is_thumb) {
472       lldb::BreakpointLocationSP bp_loc_sp(bp_site->GetOwnerAtIndex(0));
473       if (bp_loc_sp)
474         bp_is_thumb = bp_loc_sp->GetAddress().GetAddressClass() ==
475                       AddressClass::eCodeAlternateISA;
476     }
477     if (bp_is_thumb) {
478       trap_opcode = g_thumb_breakpooint_opcode;
479       trap_opcode_size = sizeof(g_thumb_breakpooint_opcode);
480       break;
481     }
482     trap_opcode = g_arm_breakpoint_opcode;
483     trap_opcode_size = sizeof(g_arm_breakpoint_opcode);
484   } break;
485 
486   case llvm::Triple::ppc:
487   case llvm::Triple::ppc64: {
488     static const uint8_t g_ppc_breakpoint_opcode[] = {0x7F, 0xC0, 0x00, 0x08};
489     trap_opcode = g_ppc_breakpoint_opcode;
490     trap_opcode_size = sizeof(g_ppc_breakpoint_opcode);
491   } break;
492 
493   default:
494     return Platform::GetSoftwareBreakpointTrapOpcode(target, bp_site);
495   }
496 
497   if (trap_opcode && trap_opcode_size) {
498     if (bp_site->SetTrapOpcode(trap_opcode, trap_opcode_size))
499       return trap_opcode_size;
500   }
501   return 0;
502 }
503 
504 bool PlatformDarwin::ModuleIsExcludedForUnconstrainedSearches(
505     lldb_private::Target &target, const lldb::ModuleSP &module_sp) {
506   if (!module_sp)
507     return false;
508 
509   ObjectFile *obj_file = module_sp->GetObjectFile();
510   if (!obj_file)
511     return false;
512 
513   ObjectFile::Type obj_type = obj_file->GetType();
514   return obj_type == ObjectFile::eTypeDynamicLinker;
515 }
516 
517 bool PlatformDarwin::x86GetSupportedArchitectureAtIndex(uint32_t idx,
518                                                         ArchSpec &arch) {
519   ArchSpec host_arch = HostInfo::GetArchitecture(HostInfo::eArchKindDefault);
520   if (host_arch.GetCore() == ArchSpec::eCore_x86_64_x86_64h) {
521     switch (idx) {
522     case 0:
523       arch = host_arch;
524       return true;
525 
526     case 1:
527       arch.SetTriple("x86_64-apple-macosx");
528       return true;
529 
530     case 2:
531       arch = HostInfo::GetArchitecture(HostInfo::eArchKind32);
532       return true;
533 
534     default:
535       return false;
536     }
537   } else {
538     if (idx == 0) {
539       arch = HostInfo::GetArchitecture(HostInfo::eArchKindDefault);
540       return arch.IsValid();
541     } else if (idx == 1) {
542       ArchSpec platform_arch(
543           HostInfo::GetArchitecture(HostInfo::eArchKindDefault));
544       ArchSpec platform_arch64(
545           HostInfo::GetArchitecture(HostInfo::eArchKind64));
546       if (platform_arch.IsExactMatch(platform_arch64)) {
547         // This macosx platform supports both 32 and 64 bit. Since we already
548         // returned the 64 bit arch for idx == 0, return the 32 bit arch for
549         // idx == 1
550         arch = HostInfo::GetArchitecture(HostInfo::eArchKind32);
551         return arch.IsValid();
552       }
553     }
554   }
555   return false;
556 }
557 
558 static llvm::ArrayRef<const char *> GetCompatibleArchs(ArchSpec::Core core) {
559   switch (core) {
560   default:
561     LLVM_FALLTHROUGH;
562   case ArchSpec::eCore_arm_arm64e: {
563     static const char *g_arm64e_compatible_archs[] = {
564         "arm64e",    "arm64",    "armv7",    "armv7f",   "armv7k",   "armv7s",
565         "armv7m",    "armv7em",  "armv6m",   "armv6",    "armv5",    "armv4",
566         "arm",       "thumbv7",  "thumbv7f", "thumbv7k", "thumbv7s", "thumbv7m",
567         "thumbv7em", "thumbv6m", "thumbv6",  "thumbv5",  "thumbv4t", "thumb",
568     };
569     return {g_arm64e_compatible_archs};
570   }
571   case ArchSpec::eCore_arm_arm64: {
572     static const char *g_arm64_compatible_archs[] = {
573         "arm64",    "armv7",    "armv7f",   "armv7k",   "armv7s",   "armv7m",
574         "armv7em",  "armv6m",   "armv6",    "armv5",    "armv4",    "arm",
575         "thumbv7",  "thumbv7f", "thumbv7k", "thumbv7s", "thumbv7m", "thumbv7em",
576         "thumbv6m", "thumbv6",  "thumbv5",  "thumbv4t", "thumb",
577     };
578     return {g_arm64_compatible_archs};
579   }
580   case ArchSpec::eCore_arm_armv7: {
581     static const char *g_armv7_compatible_archs[] = {
582         "armv7",   "armv6m",   "armv6",   "armv5",   "armv4",    "arm",
583         "thumbv7", "thumbv6m", "thumbv6", "thumbv5", "thumbv4t", "thumb",
584     };
585     return {g_armv7_compatible_archs};
586   }
587   case ArchSpec::eCore_arm_armv7f: {
588     static const char *g_armv7f_compatible_archs[] = {
589         "armv7f",  "armv7",   "armv6m",   "armv6",   "armv5",
590         "armv4",   "arm",     "thumbv7f", "thumbv7", "thumbv6m",
591         "thumbv6", "thumbv5", "thumbv4t", "thumb",
592     };
593     return {g_armv7f_compatible_archs};
594   }
595   case ArchSpec::eCore_arm_armv7k: {
596     static const char *g_armv7k_compatible_archs[] = {
597         "armv7k",  "armv7",   "armv6m",   "armv6",   "armv5",
598         "armv4",   "arm",     "thumbv7k", "thumbv7", "thumbv6m",
599         "thumbv6", "thumbv5", "thumbv4t", "thumb",
600     };
601     return {g_armv7k_compatible_archs};
602   }
603   case ArchSpec::eCore_arm_armv7s: {
604     static const char *g_armv7s_compatible_archs[] = {
605         "armv7s",  "armv7",   "armv6m",   "armv6",   "armv5",
606         "armv4",   "arm",     "thumbv7s", "thumbv7", "thumbv6m",
607         "thumbv6", "thumbv5", "thumbv4t", "thumb",
608     };
609     return {g_armv7s_compatible_archs};
610   }
611   case ArchSpec::eCore_arm_armv7m: {
612     static const char *g_armv7m_compatible_archs[] = {
613         "armv7m",  "armv7",   "armv6m",   "armv6",   "armv5",
614         "armv4",   "arm",     "thumbv7m", "thumbv7", "thumbv6m",
615         "thumbv6", "thumbv5", "thumbv4t", "thumb",
616     };
617     return {g_armv7m_compatible_archs};
618   }
619   case ArchSpec::eCore_arm_armv7em: {
620     static const char *g_armv7em_compatible_archs[] = {
621         "armv7em", "armv7",   "armv6m",    "armv6",   "armv5",
622         "armv4",   "arm",     "thumbv7em", "thumbv7", "thumbv6m",
623         "thumbv6", "thumbv5", "thumbv4t",  "thumb",
624     };
625     return {g_armv7em_compatible_archs};
626   }
627   case ArchSpec::eCore_arm_armv6m: {
628     static const char *g_armv6m_compatible_archs[] = {
629         "armv6m",   "armv6",   "armv5",   "armv4",    "arm",
630         "thumbv6m", "thumbv6", "thumbv5", "thumbv4t", "thumb",
631     };
632     return {g_armv6m_compatible_archs};
633   }
634   case ArchSpec::eCore_arm_armv6: {
635     static const char *g_armv6_compatible_archs[] = {
636         "armv6",   "armv5",   "armv4",    "arm",
637         "thumbv6", "thumbv5", "thumbv4t", "thumb",
638     };
639     return {g_armv6_compatible_archs};
640   }
641   case ArchSpec::eCore_arm_armv5: {
642     static const char *g_armv5_compatible_archs[] = {
643         "armv5", "armv4", "arm", "thumbv5", "thumbv4t", "thumb",
644     };
645     return {g_armv5_compatible_archs};
646   }
647   case ArchSpec::eCore_arm_armv4: {
648     static const char *g_armv4_compatible_archs[] = {
649         "armv4",
650         "arm",
651         "thumbv4t",
652         "thumb",
653     };
654     return {g_armv4_compatible_archs};
655   }
656   }
657   return {};
658 }
659 
660 const char *PlatformDarwin::GetCompatibleArch(ArchSpec::Core core, size_t idx) {
661   llvm::ArrayRef<const char *> compatible_archs = GetCompatibleArchs(core);
662   if (!compatible_archs.data())
663     return nullptr;
664   if (idx < compatible_archs.size())
665     return compatible_archs[idx];
666   return nullptr;
667 }
668 
669 /// The architecture selection rules for arm processors These cpu subtypes have
670 /// distinct names (e.g. armv7f) but armv7 binaries run fine on an armv7f
671 /// processor.
672 bool PlatformDarwin::ARMGetSupportedArchitectureAtIndex(uint32_t idx,
673                                                         ArchSpec &arch) {
674   const ArchSpec system_arch = GetSystemArchitecture();
675   const ArchSpec::Core system_core = system_arch.GetCore();
676 
677   if (const char *compatible_arch = GetCompatibleArch(system_core, idx)) {
678     llvm::Triple triple;
679     triple.setArchName(compatible_arch);
680     triple.setVendor(llvm::Triple::VendorType::Apple);
681     arch.SetTriple(triple);
682     return true;
683   }
684 
685   arch.Clear();
686   return false;
687 }
688 
689 static FileSpec GetXcodeSelectPath() {
690   static FileSpec g_xcode_select_filespec;
691 
692   if (!g_xcode_select_filespec) {
693     FileSpec xcode_select_cmd("/usr/bin/xcode-select");
694     if (FileSystem::Instance().Exists(xcode_select_cmd)) {
695       int exit_status = -1;
696       int signo = -1;
697       std::string command_output;
698       Status status =
699           Host::RunShellCommand("/usr/bin/xcode-select --print-path",
700                                 FileSpec(), // current working directory
701                                 &exit_status, &signo, &command_output,
702                                 std::chrono::seconds(2), // short timeout
703                                 false);                  // don't run in a shell
704       if (status.Success() && exit_status == 0 && !command_output.empty()) {
705         size_t first_non_newline = command_output.find_last_not_of("\r\n");
706         if (first_non_newline != std::string::npos) {
707           command_output.erase(first_non_newline + 1);
708         }
709         g_xcode_select_filespec = FileSpec(command_output);
710       }
711     }
712   }
713 
714   return g_xcode_select_filespec;
715 }
716 
717 BreakpointSP PlatformDarwin::SetThreadCreationBreakpoint(Target &target) {
718   BreakpointSP bp_sp;
719   static const char *g_bp_names[] = {
720       "start_wqthread", "_pthread_wqthread", "_pthread_start",
721   };
722 
723   static const char *g_bp_modules[] = {"libsystem_c.dylib",
724                                        "libSystem.B.dylib"};
725 
726   FileSpecList bp_modules;
727   for (size_t i = 0; i < llvm::array_lengthof(g_bp_modules); i++) {
728     const char *bp_module = g_bp_modules[i];
729     bp_modules.EmplaceBack(bp_module);
730   }
731 
732   bool internal = true;
733   bool hardware = false;
734   LazyBool skip_prologue = eLazyBoolNo;
735   bp_sp = target.CreateBreakpoint(&bp_modules, nullptr, g_bp_names,
736                                   llvm::array_lengthof(g_bp_names),
737                                   eFunctionNameTypeFull, eLanguageTypeUnknown,
738                                   0, skip_prologue, internal, hardware);
739   bp_sp->SetBreakpointKind("thread-creation");
740 
741   return bp_sp;
742 }
743 
744 uint32_t
745 PlatformDarwin::GetResumeCountForLaunchInfo(ProcessLaunchInfo &launch_info) {
746   const FileSpec &shell = launch_info.GetShell();
747   if (!shell)
748     return 1;
749 
750   std::string shell_string = shell.GetPath();
751   const char *shell_name = strrchr(shell_string.c_str(), '/');
752   if (shell_name == nullptr)
753     shell_name = shell_string.c_str();
754   else
755     shell_name++;
756 
757   if (strcmp(shell_name, "sh") == 0) {
758     // /bin/sh re-exec's itself as /bin/bash requiring another resume. But it
759     // only does this if the COMMAND_MODE environment variable is set to
760     // "legacy".
761     if (launch_info.GetEnvironment().lookup("COMMAND_MODE") == "legacy")
762       return 2;
763     return 1;
764   } else if (strcmp(shell_name, "csh") == 0 ||
765              strcmp(shell_name, "tcsh") == 0 ||
766              strcmp(shell_name, "zsh") == 0) {
767     // csh and tcsh always seem to re-exec themselves.
768     return 2;
769   } else
770     return 1;
771 }
772 
773 lldb::ProcessSP PlatformDarwin::DebugProcess(ProcessLaunchInfo &launch_info,
774                                              Debugger &debugger, Target &target,
775                                              Status &error) {
776   ProcessSP process_sp;
777 
778   if (IsHost()) {
779     // We are going to hand this process off to debugserver which will be in
780     // charge of setting the exit status.  However, we still need to reap it
781     // from lldb. So, make sure we use a exit callback which does not set exit
782     // status.
783     const bool monitor_signals = false;
784     launch_info.SetMonitorProcessCallback(
785         &ProcessLaunchInfo::NoOpMonitorCallback, monitor_signals);
786     process_sp = Platform::DebugProcess(launch_info, debugger, target, error);
787   } else {
788     if (m_remote_platform_sp)
789       process_sp = m_remote_platform_sp->DebugProcess(launch_info, debugger,
790                                                       target, error);
791     else
792       error.SetErrorString("the platform is not currently connected");
793   }
794   return process_sp;
795 }
796 
797 void PlatformDarwin::CalculateTrapHandlerSymbolNames() {
798   m_trap_handlers.push_back(ConstString("_sigtramp"));
799 }
800 
801 static FileSpec GetCommandLineToolsLibraryPath() {
802   static FileSpec g_command_line_tools_filespec;
803 
804   if (!g_command_line_tools_filespec) {
805     FileSpec command_line_tools_path(GetXcodeSelectPath());
806     command_line_tools_path.AppendPathComponent("Library");
807     if (FileSystem::Instance().Exists(command_line_tools_path)) {
808       g_command_line_tools_filespec = command_line_tools_path;
809     }
810   }
811 
812   return g_command_line_tools_filespec;
813 }
814 
815 FileSystem::EnumerateDirectoryResult PlatformDarwin::DirectoryEnumerator(
816     void *baton, llvm::sys::fs::file_type file_type, llvm::StringRef path) {
817   SDKEnumeratorInfo *enumerator_info = static_cast<SDKEnumeratorInfo *>(baton);
818 
819   FileSpec spec(path);
820   if (XcodeSDK::SDKSupportsModules(enumerator_info->sdk_type, spec)) {
821     enumerator_info->found_path = spec;
822     return FileSystem::EnumerateDirectoryResult::eEnumerateDirectoryResultNext;
823   }
824 
825   return FileSystem::EnumerateDirectoryResult::eEnumerateDirectoryResultNext;
826 }
827 
828 FileSpec PlatformDarwin::FindSDKInXcodeForModules(XcodeSDK::Type sdk_type,
829                                                   const FileSpec &sdks_spec) {
830   // Look inside Xcode for the required installed iOS SDK version
831 
832   if (!FileSystem::Instance().IsDirectory(sdks_spec)) {
833     return FileSpec();
834   }
835 
836   const bool find_directories = true;
837   const bool find_files = false;
838   const bool find_other = true; // include symlinks
839 
840   SDKEnumeratorInfo enumerator_info;
841 
842   enumerator_info.sdk_type = sdk_type;
843 
844   FileSystem::Instance().EnumerateDirectory(
845       sdks_spec.GetPath(), find_directories, find_files, find_other,
846       DirectoryEnumerator, &enumerator_info);
847 
848   if (FileSystem::Instance().IsDirectory(enumerator_info.found_path))
849     return enumerator_info.found_path;
850   else
851     return FileSpec();
852 }
853 
854 FileSpec PlatformDarwin::GetSDKDirectoryForModules(XcodeSDK::Type sdk_type) {
855   FileSpec sdks_spec = HostInfo::GetXcodeContentsDirectory();
856   sdks_spec.AppendPathComponent("Developer");
857   sdks_spec.AppendPathComponent("Platforms");
858 
859   switch (sdk_type) {
860   case XcodeSDK::Type::MacOSX:
861     sdks_spec.AppendPathComponent("MacOSX.platform");
862     break;
863   case XcodeSDK::Type::iPhoneSimulator:
864     sdks_spec.AppendPathComponent("iPhoneSimulator.platform");
865     break;
866   case XcodeSDK::Type::iPhoneOS:
867     sdks_spec.AppendPathComponent("iPhoneOS.platform");
868     break;
869   case XcodeSDK::Type::WatchSimulator:
870     sdks_spec.AppendPathComponent("WatchSimulator.platform");
871     break;
872   case XcodeSDK::Type::AppleTVSimulator:
873     sdks_spec.AppendPathComponent("AppleTVSimulator.platform");
874     break;
875   default:
876     llvm_unreachable("unsupported sdk");
877   }
878 
879   sdks_spec.AppendPathComponent("Developer");
880   sdks_spec.AppendPathComponent("SDKs");
881 
882   if (sdk_type == XcodeSDK::Type::MacOSX) {
883     llvm::VersionTuple version = HostInfo::GetOSVersion();
884 
885     if (!version.empty()) {
886       if (XcodeSDK::SDKSupportsModules(XcodeSDK::Type::MacOSX, version)) {
887         // If the Xcode SDKs are not available then try to use the
888         // Command Line Tools one which is only for MacOSX.
889         if (!FileSystem::Instance().Exists(sdks_spec)) {
890           sdks_spec = GetCommandLineToolsLibraryPath();
891           sdks_spec.AppendPathComponent("SDKs");
892         }
893 
894         // We slightly prefer the exact SDK for this machine.  See if it is
895         // there.
896 
897         FileSpec native_sdk_spec = sdks_spec;
898         StreamString native_sdk_name;
899         native_sdk_name.Printf("MacOSX%u.%u.sdk", version.getMajor(),
900                                version.getMinor().getValueOr(0));
901         native_sdk_spec.AppendPathComponent(native_sdk_name.GetString());
902 
903         if (FileSystem::Instance().Exists(native_sdk_spec)) {
904           return native_sdk_spec;
905         }
906       }
907     }
908   }
909 
910   return FindSDKInXcodeForModules(sdk_type, sdks_spec);
911 }
912 
913 std::tuple<llvm::VersionTuple, llvm::StringRef>
914 PlatformDarwin::ParseVersionBuildDir(llvm::StringRef dir) {
915   llvm::StringRef build;
916   llvm::StringRef version_str;
917   llvm::StringRef build_str;
918   std::tie(version_str, build_str) = dir.split(' ');
919   llvm::VersionTuple version;
920   if (!version.tryParse(version_str) ||
921       build_str.empty()) {
922     if (build_str.consume_front("(")) {
923       size_t pos = build_str.find(')');
924       build = build_str.slice(0, pos);
925     }
926   }
927 
928   return std::make_tuple(version, build);
929 }
930 
931 llvm::Expected<StructuredData::DictionarySP>
932 PlatformDarwin::FetchExtendedCrashInformation(Process &process) {
933   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
934 
935   StructuredData::ArraySP annotations = ExtractCrashInfoAnnotations(process);
936 
937   if (!annotations || !annotations->GetSize()) {
938     LLDB_LOG(log, "Couldn't extract crash information annotations");
939     return nullptr;
940   }
941 
942   StructuredData::DictionarySP extended_crash_info =
943       std::make_shared<StructuredData::Dictionary>();
944 
945   extended_crash_info->AddItem("crash-info annotations", annotations);
946 
947   return extended_crash_info;
948 }
949 
950 StructuredData::ArraySP
951 PlatformDarwin::ExtractCrashInfoAnnotations(Process &process) {
952   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
953 
954   ConstString section_name("__crash_info");
955   Target &target = process.GetTarget();
956   StructuredData::ArraySP array_sp = std::make_shared<StructuredData::Array>();
957 
958   for (ModuleSP module : target.GetImages().Modules()) {
959     SectionList *sections = module->GetSectionList();
960 
961     std::string module_name = module->GetSpecificationDescription();
962 
963     // The DYDL module is skipped since it's always loaded when running the
964     // binary.
965     if (module_name == "/usr/lib/dyld")
966       continue;
967 
968     if (!sections) {
969       LLDB_LOG(log, "Module {0} doesn't have any section!", module_name);
970       continue;
971     }
972 
973     SectionSP crash_info = sections->FindSectionByName(section_name);
974     if (!crash_info) {
975       LLDB_LOG(log, "Module {0} doesn't have section {1}!", module_name,
976                section_name);
977       continue;
978     }
979 
980     addr_t load_addr = crash_info->GetLoadBaseAddress(&target);
981 
982     if (load_addr == LLDB_INVALID_ADDRESS) {
983       LLDB_LOG(log, "Module {0} has an invalid '{1}' section load address: {2}",
984                module_name, section_name, load_addr);
985       continue;
986     }
987 
988     Status error;
989     CrashInfoAnnotations annotations;
990     size_t expected_size = sizeof(CrashInfoAnnotations);
991     size_t bytes_read = process.ReadMemoryFromInferior(load_addr, &annotations,
992                                                        expected_size, error);
993 
994     if (expected_size != bytes_read || error.Fail()) {
995       LLDB_LOG(log, "Failed to read {0} section from memory in module {1}: {2}",
996                section_name, module_name, error);
997       continue;
998     }
999 
1000     // initial support added for version 5
1001     if (annotations.version < 5) {
1002       LLDB_LOG(log,
1003                "Annotation version lower than 5 unsupported! Module {0} has "
1004                "version {1} instead.",
1005                module_name, annotations.version);
1006       continue;
1007     }
1008 
1009     if (!annotations.message) {
1010       LLDB_LOG(log, "No message available for module {0}.", module_name);
1011       continue;
1012     }
1013 
1014     std::string message;
1015     bytes_read =
1016         process.ReadCStringFromMemory(annotations.message, message, error);
1017 
1018     if (message.empty() || bytes_read != message.size() || error.Fail()) {
1019       LLDB_LOG(log, "Failed to read the message from memory in module {0}: {1}",
1020                module_name, error);
1021       continue;
1022     }
1023 
1024     // Remove trailing newline from message
1025     if (message.back() == '\n')
1026       message.pop_back();
1027 
1028     if (!annotations.message2)
1029       LLDB_LOG(log, "No message2 available for module {0}.", module_name);
1030 
1031     std::string message2;
1032     bytes_read =
1033         process.ReadCStringFromMemory(annotations.message2, message2, error);
1034 
1035     if (!message2.empty() && bytes_read == message2.size() && error.Success())
1036       if (message2.back() == '\n')
1037         message2.pop_back();
1038 
1039     StructuredData::DictionarySP entry_sp =
1040         std::make_shared<StructuredData::Dictionary>();
1041 
1042     entry_sp->AddStringItem("image", module->GetFileSpec().GetPath(false));
1043     entry_sp->AddStringItem("uuid", module->GetUUID().GetAsString());
1044     entry_sp->AddStringItem("message", message);
1045     entry_sp->AddStringItem("message2", message2);
1046     entry_sp->AddIntegerItem("abort-cause", annotations.abort_cause);
1047 
1048     array_sp->AddItem(entry_sp);
1049   }
1050 
1051   return array_sp;
1052 }
1053 
1054 void PlatformDarwin::AddClangModuleCompilationOptionsForSDKType(
1055     Target *target, std::vector<std::string> &options, XcodeSDK::Type sdk_type) {
1056   const std::vector<std::string> apple_arguments = {
1057       "-x",       "objective-c++", "-fobjc-arc",
1058       "-fblocks", "-D_ISO646_H",   "-D__ISO646_H",
1059       "-fgnuc-version=4.2.1"};
1060 
1061   options.insert(options.end(), apple_arguments.begin(), apple_arguments.end());
1062 
1063   StreamString minimum_version_option;
1064   bool use_current_os_version = false;
1065   // If the SDK type is for the host OS, use its version number.
1066   auto get_host_os = []() { return HostInfo::GetTargetTriple().getOS(); };
1067   switch (sdk_type) {
1068   case XcodeSDK::Type::MacOSX:
1069     use_current_os_version = get_host_os() == llvm::Triple::MacOSX;
1070     break;
1071   case XcodeSDK::Type::iPhoneOS:
1072     use_current_os_version = get_host_os() == llvm::Triple::IOS;
1073     break;
1074   case XcodeSDK::Type::AppleTVOS:
1075     use_current_os_version = get_host_os() == llvm::Triple::TvOS;
1076     break;
1077   case XcodeSDK::Type::watchOS:
1078     use_current_os_version = get_host_os() == llvm::Triple::WatchOS;
1079     break;
1080   default:
1081     break;
1082   }
1083 
1084   llvm::VersionTuple version;
1085   if (use_current_os_version)
1086     version = GetOSVersion();
1087   else if (target) {
1088     // Our OS doesn't match our executable so we need to get the min OS version
1089     // from the object file
1090     ModuleSP exe_module_sp = target->GetExecutableModule();
1091     if (exe_module_sp) {
1092       ObjectFile *object_file = exe_module_sp->GetObjectFile();
1093       if (object_file)
1094         version = object_file->GetMinimumOSVersion();
1095     }
1096   }
1097   // Only add the version-min options if we got a version from somewhere
1098   if (!version.empty() && sdk_type != XcodeSDK::Type::Linux) {
1099 #define OPTION(PREFIX, NAME, VAR, ...)                                         \
1100   const char *opt_##VAR = NAME;                                                \
1101   (void)opt_##VAR;
1102 #include "clang/Driver/Options.inc"
1103 #undef OPTION
1104     minimum_version_option << '-';
1105     switch (sdk_type) {
1106     case XcodeSDK::Type::MacOSX:
1107       minimum_version_option << opt_mmacosx_version_min_EQ;
1108       break;
1109     case XcodeSDK::Type::iPhoneSimulator:
1110       minimum_version_option << opt_mios_simulator_version_min_EQ;
1111       break;
1112     case XcodeSDK::Type::iPhoneOS:
1113       minimum_version_option << opt_mios_version_min_EQ;
1114       break;
1115     case XcodeSDK::Type::AppleTVSimulator:
1116       minimum_version_option << opt_mtvos_simulator_version_min_EQ;
1117       break;
1118     case XcodeSDK::Type::AppleTVOS:
1119       minimum_version_option << opt_mtvos_version_min_EQ;
1120       break;
1121     case XcodeSDK::Type::WatchSimulator:
1122       minimum_version_option << opt_mwatchos_simulator_version_min_EQ;
1123       break;
1124     case XcodeSDK::Type::watchOS:
1125       minimum_version_option << opt_mwatchos_version_min_EQ;
1126       break;
1127     case XcodeSDK::Type::bridgeOS:
1128     case XcodeSDK::Type::Linux:
1129     case XcodeSDK::Type::unknown:
1130       if (lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST)) {
1131         XcodeSDK::Info info;
1132         info.type = sdk_type;
1133         LLDB_LOGF(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST),
1134                   "Clang modules on %s are not supported",
1135                   XcodeSDK::GetCanonicalName(info).c_str());
1136       }
1137       return;
1138     }
1139     minimum_version_option << version.getAsString();
1140     options.emplace_back(std::string(minimum_version_option.GetString()));
1141   }
1142 
1143   FileSpec sysroot_spec;
1144   // Scope for mutex locker below
1145   {
1146     std::lock_guard<std::mutex> guard(m_mutex);
1147     sysroot_spec = GetSDKDirectoryForModules(sdk_type);
1148   }
1149 
1150   if (FileSystem::Instance().IsDirectory(sysroot_spec.GetPath())) {
1151     options.push_back("-isysroot");
1152     options.push_back(sysroot_spec.GetPath());
1153   }
1154 }
1155 
1156 ConstString PlatformDarwin::GetFullNameForDylib(ConstString basename) {
1157   if (basename.IsEmpty())
1158     return basename;
1159 
1160   StreamString stream;
1161   stream.Printf("lib%s.dylib", basename.GetCString());
1162   return ConstString(stream.GetString());
1163 }
1164 
1165 llvm::VersionTuple PlatformDarwin::GetOSVersion(Process *process) {
1166   if (process && GetPluginName().contains("-simulator")) {
1167     lldb_private::ProcessInstanceInfo proc_info;
1168     if (Host::GetProcessInfo(process->GetID(), proc_info)) {
1169       const Environment &env = proc_info.GetEnvironment();
1170 
1171       llvm::VersionTuple result;
1172       if (!result.tryParse(env.lookup("SIMULATOR_RUNTIME_VERSION")))
1173         return result;
1174 
1175       std::string dyld_root_path = env.lookup("DYLD_ROOT_PATH");
1176       if (!dyld_root_path.empty()) {
1177         dyld_root_path += "/System/Library/CoreServices/SystemVersion.plist";
1178         ApplePropertyList system_version_plist(dyld_root_path.c_str());
1179         std::string product_version;
1180         if (system_version_plist.GetValueAsString("ProductVersion",
1181                                                   product_version)) {
1182           if (!result.tryParse(product_version))
1183             return result;
1184         }
1185       }
1186     }
1187     // For simulator platforms, do NOT call back through
1188     // Platform::GetOSVersion() as it might call Process::GetHostOSVersion()
1189     // which we don't want as it will be incorrect
1190     return llvm::VersionTuple();
1191   }
1192 
1193   return Platform::GetOSVersion(process);
1194 }
1195 
1196 lldb_private::FileSpec PlatformDarwin::LocateExecutable(const char *basename) {
1197   // A collection of SBFileSpec whose SBFileSpec.m_directory members are filled
1198   // in with any executable directories that should be searched.
1199   static std::vector<FileSpec> g_executable_dirs;
1200 
1201   // Find the global list of directories that we will search for executables
1202   // once so we don't keep doing the work over and over.
1203   static llvm::once_flag g_once_flag;
1204   llvm::call_once(g_once_flag, []() {
1205 
1206     // When locating executables, trust the DEVELOPER_DIR first if it is set
1207     FileSpec xcode_contents_dir = HostInfo::GetXcodeContentsDirectory();
1208     if (xcode_contents_dir) {
1209       FileSpec xcode_lldb_resources = xcode_contents_dir;
1210       xcode_lldb_resources.AppendPathComponent("SharedFrameworks");
1211       xcode_lldb_resources.AppendPathComponent("LLDB.framework");
1212       xcode_lldb_resources.AppendPathComponent("Resources");
1213       if (FileSystem::Instance().Exists(xcode_lldb_resources)) {
1214         FileSpec dir;
1215         dir.GetDirectory().SetCString(xcode_lldb_resources.GetPath().c_str());
1216         g_executable_dirs.push_back(dir);
1217       }
1218     }
1219     // Xcode might not be installed so we also check for the Command Line Tools.
1220     FileSpec command_line_tools_dir = GetCommandLineToolsLibraryPath();
1221     if (command_line_tools_dir) {
1222       FileSpec cmd_line_lldb_resources = command_line_tools_dir;
1223       cmd_line_lldb_resources.AppendPathComponent("PrivateFrameworks");
1224       cmd_line_lldb_resources.AppendPathComponent("LLDB.framework");
1225       cmd_line_lldb_resources.AppendPathComponent("Resources");
1226       if (FileSystem::Instance().Exists(cmd_line_lldb_resources)) {
1227         FileSpec dir;
1228         dir.GetDirectory().SetCString(
1229             cmd_line_lldb_resources.GetPath().c_str());
1230         g_executable_dirs.push_back(dir);
1231       }
1232     }
1233   });
1234 
1235   // Now search the global list of executable directories for the executable we
1236   // are looking for
1237   for (const auto &executable_dir : g_executable_dirs) {
1238     FileSpec executable_file;
1239     executable_file.GetDirectory() = executable_dir.GetDirectory();
1240     executable_file.GetFilename().SetCString(basename);
1241     if (FileSystem::Instance().Exists(executable_file))
1242       return executable_file;
1243   }
1244 
1245   return FileSpec();
1246 }
1247 
1248 lldb_private::Status
1249 PlatformDarwin::LaunchProcess(lldb_private::ProcessLaunchInfo &launch_info) {
1250   // Starting in Fall 2016 OSes, NSLog messages only get mirrored to stderr if
1251   // the OS_ACTIVITY_DT_MODE environment variable is set.  (It doesn't require
1252   // any specific value; rather, it just needs to exist). We will set it here
1253   // as long as the IDE_DISABLED_OS_ACTIVITY_DT_MODE flag is not set.  Xcode
1254   // makes use of IDE_DISABLED_OS_ACTIVITY_DT_MODE to tell
1255   // LLDB *not* to muck with the OS_ACTIVITY_DT_MODE flag when they
1256   // specifically want it unset.
1257   const char *disable_env_var = "IDE_DISABLED_OS_ACTIVITY_DT_MODE";
1258   auto &env_vars = launch_info.GetEnvironment();
1259   if (!env_vars.count(disable_env_var)) {
1260     // We want to make sure that OS_ACTIVITY_DT_MODE is set so that we get
1261     // os_log and NSLog messages mirrored to the target process stderr.
1262     env_vars.try_emplace("OS_ACTIVITY_DT_MODE", "enable");
1263   }
1264 
1265   // Let our parent class do the real launching.
1266   return PlatformPOSIX::LaunchProcess(launch_info);
1267 }
1268 
1269 lldb_private::Status PlatformDarwin::FindBundleBinaryInExecSearchPaths(
1270     const ModuleSpec &module_spec, Process *process, ModuleSP &module_sp,
1271     const FileSpecList *module_search_paths_ptr,
1272     llvm::SmallVectorImpl<ModuleSP> *old_modules, bool *did_create_ptr) {
1273   const FileSpec &platform_file = module_spec.GetFileSpec();
1274   // See if the file is present in any of the module_search_paths_ptr
1275   // directories.
1276   if (!module_sp && module_search_paths_ptr && platform_file) {
1277     // create a vector of all the file / directory names in platform_file e.g.
1278     // this might be
1279     // /System/Library/PrivateFrameworks/UIFoundation.framework/UIFoundation
1280     //
1281     // We'll need to look in the module_search_paths_ptr directories for both
1282     // "UIFoundation" and "UIFoundation.framework" -- most likely the latter
1283     // will be the one we find there.
1284 
1285     FileSpec platform_pull_upart(platform_file);
1286     std::vector<std::string> path_parts;
1287     path_parts.push_back(
1288         platform_pull_upart.GetLastPathComponent().AsCString());
1289     while (platform_pull_upart.RemoveLastPathComponent()) {
1290       ConstString part = platform_pull_upart.GetLastPathComponent();
1291       path_parts.push_back(part.AsCString());
1292     }
1293     const size_t path_parts_size = path_parts.size();
1294 
1295     size_t num_module_search_paths = module_search_paths_ptr->GetSize();
1296     for (size_t i = 0; i < num_module_search_paths; ++i) {
1297       Log *log_verbose = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST);
1298       LLDB_LOGF(
1299           log_verbose,
1300           "PlatformRemoteDarwinDevice::GetSharedModule searching for binary in "
1301           "search-path %s",
1302           module_search_paths_ptr->GetFileSpecAtIndex(i).GetPath().c_str());
1303       // Create a new FileSpec with this module_search_paths_ptr plus just the
1304       // filename ("UIFoundation"), then the parent dir plus filename
1305       // ("UIFoundation.framework/UIFoundation") etc - up to four names (to
1306       // handle "Foo.framework/Contents/MacOS/Foo")
1307 
1308       for (size_t j = 0; j < 4 && j < path_parts_size - 1; ++j) {
1309         FileSpec path_to_try(module_search_paths_ptr->GetFileSpecAtIndex(i));
1310 
1311         // Add the components backwards.  For
1312         // .../PrivateFrameworks/UIFoundation.framework/UIFoundation path_parts
1313         // is
1314         //   [0] UIFoundation
1315         //   [1] UIFoundation.framework
1316         //   [2] PrivateFrameworks
1317         //
1318         // and if 'j' is 2, we want to append path_parts[1] and then
1319         // path_parts[0], aka 'UIFoundation.framework/UIFoundation', to the
1320         // module_search_paths_ptr path.
1321 
1322         for (int k = j; k >= 0; --k) {
1323           path_to_try.AppendPathComponent(path_parts[k]);
1324         }
1325 
1326         if (FileSystem::Instance().Exists(path_to_try)) {
1327           ModuleSpec new_module_spec(module_spec);
1328           new_module_spec.GetFileSpec() = path_to_try;
1329           Status new_error(
1330               Platform::GetSharedModule(new_module_spec, process, module_sp,
1331                                         nullptr, old_modules, did_create_ptr));
1332 
1333           if (module_sp) {
1334             module_sp->SetPlatformFileSpec(path_to_try);
1335             return new_error;
1336           }
1337         }
1338       }
1339     }
1340   }
1341   return Status();
1342 }
1343 
1344 std::string PlatformDarwin::FindComponentInPath(llvm::StringRef path,
1345                                                 llvm::StringRef component) {
1346   auto begin = llvm::sys::path::begin(path);
1347   auto end = llvm::sys::path::end(path);
1348   for (auto it = begin; it != end; ++it) {
1349     if (it->contains(component)) {
1350       llvm::SmallString<128> buffer;
1351       llvm::sys::path::append(buffer, begin, ++it,
1352                               llvm::sys::path::Style::posix);
1353       return buffer.str().str();
1354     }
1355   }
1356   return {};
1357 }
1358 
1359 FileSpec PlatformDarwin::GetCurrentToolchainDirectory() {
1360   if (FileSpec fspec = HostInfo::GetShlibDir())
1361     return FileSpec(FindComponentInPath(fspec.GetPath(), ".xctoolchain"));
1362   return {};
1363 }
1364 
1365 FileSpec PlatformDarwin::GetCurrentCommandLineToolsDirectory() {
1366   if (FileSpec fspec = HostInfo::GetShlibDir())
1367     return FileSpec(FindComponentInPath(fspec.GetPath(), "CommandLineTools"));
1368   return {};
1369 }
1370