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 void PlatformDarwin::x86GetSupportedArchitectures(
518     std::vector<ArchSpec> &archs) {
519   ArchSpec host_arch = HostInfo::GetArchitecture(HostInfo::eArchKindDefault);
520   archs.push_back(host_arch);
521 
522   if (host_arch.GetCore() == ArchSpec::eCore_x86_64_x86_64h) {
523     archs.push_back(ArchSpec("x86_64-apple-macosx"));
524     archs.push_back(HostInfo::GetArchitecture(HostInfo::eArchKind32));
525   } else {
526     ArchSpec host_arch64 = HostInfo::GetArchitecture(HostInfo::eArchKind64);
527     if (host_arch.IsExactMatch(host_arch64))
528       archs.push_back(HostInfo::GetArchitecture(HostInfo::eArchKind32));
529   }
530 }
531 
532 static llvm::ArrayRef<const char *> GetCompatibleArchs(ArchSpec::Core core) {
533   switch (core) {
534   default:
535     LLVM_FALLTHROUGH;
536   case ArchSpec::eCore_arm_arm64e: {
537     static const char *g_arm64e_compatible_archs[] = {
538         "arm64e",    "arm64",    "armv7",    "armv7f",   "armv7k",   "armv7s",
539         "armv7m",    "armv7em",  "armv6m",   "armv6",    "armv5",    "armv4",
540         "arm",       "thumbv7",  "thumbv7f", "thumbv7k", "thumbv7s", "thumbv7m",
541         "thumbv7em", "thumbv6m", "thumbv6",  "thumbv5",  "thumbv4t", "thumb",
542     };
543     return {g_arm64e_compatible_archs};
544   }
545   case ArchSpec::eCore_arm_arm64: {
546     static const char *g_arm64_compatible_archs[] = {
547         "arm64",    "armv7",    "armv7f",   "armv7k",   "armv7s",   "armv7m",
548         "armv7em",  "armv6m",   "armv6",    "armv5",    "armv4",    "arm",
549         "thumbv7",  "thumbv7f", "thumbv7k", "thumbv7s", "thumbv7m", "thumbv7em",
550         "thumbv6m", "thumbv6",  "thumbv5",  "thumbv4t", "thumb",
551     };
552     return {g_arm64_compatible_archs};
553   }
554   case ArchSpec::eCore_arm_armv7: {
555     static const char *g_armv7_compatible_archs[] = {
556         "armv7",   "armv6m",   "armv6",   "armv5",   "armv4",    "arm",
557         "thumbv7", "thumbv6m", "thumbv6", "thumbv5", "thumbv4t", "thumb",
558     };
559     return {g_armv7_compatible_archs};
560   }
561   case ArchSpec::eCore_arm_armv7f: {
562     static const char *g_armv7f_compatible_archs[] = {
563         "armv7f",  "armv7",   "armv6m",   "armv6",   "armv5",
564         "armv4",   "arm",     "thumbv7f", "thumbv7", "thumbv6m",
565         "thumbv6", "thumbv5", "thumbv4t", "thumb",
566     };
567     return {g_armv7f_compatible_archs};
568   }
569   case ArchSpec::eCore_arm_armv7k: {
570     static const char *g_armv7k_compatible_archs[] = {
571         "armv7k",  "armv7",   "armv6m",   "armv6",   "armv5",
572         "armv4",   "arm",     "thumbv7k", "thumbv7", "thumbv6m",
573         "thumbv6", "thumbv5", "thumbv4t", "thumb",
574     };
575     return {g_armv7k_compatible_archs};
576   }
577   case ArchSpec::eCore_arm_armv7s: {
578     static const char *g_armv7s_compatible_archs[] = {
579         "armv7s",  "armv7",   "armv6m",   "armv6",   "armv5",
580         "armv4",   "arm",     "thumbv7s", "thumbv7", "thumbv6m",
581         "thumbv6", "thumbv5", "thumbv4t", "thumb",
582     };
583     return {g_armv7s_compatible_archs};
584   }
585   case ArchSpec::eCore_arm_armv7m: {
586     static const char *g_armv7m_compatible_archs[] = {
587         "armv7m",  "armv7",   "armv6m",   "armv6",   "armv5",
588         "armv4",   "arm",     "thumbv7m", "thumbv7", "thumbv6m",
589         "thumbv6", "thumbv5", "thumbv4t", "thumb",
590     };
591     return {g_armv7m_compatible_archs};
592   }
593   case ArchSpec::eCore_arm_armv7em: {
594     static const char *g_armv7em_compatible_archs[] = {
595         "armv7em", "armv7",   "armv6m",    "armv6",   "armv5",
596         "armv4",   "arm",     "thumbv7em", "thumbv7", "thumbv6m",
597         "thumbv6", "thumbv5", "thumbv4t",  "thumb",
598     };
599     return {g_armv7em_compatible_archs};
600   }
601   case ArchSpec::eCore_arm_armv6m: {
602     static const char *g_armv6m_compatible_archs[] = {
603         "armv6m",   "armv6",   "armv5",   "armv4",    "arm",
604         "thumbv6m", "thumbv6", "thumbv5", "thumbv4t", "thumb",
605     };
606     return {g_armv6m_compatible_archs};
607   }
608   case ArchSpec::eCore_arm_armv6: {
609     static const char *g_armv6_compatible_archs[] = {
610         "armv6",   "armv5",   "armv4",    "arm",
611         "thumbv6", "thumbv5", "thumbv4t", "thumb",
612     };
613     return {g_armv6_compatible_archs};
614   }
615   case ArchSpec::eCore_arm_armv5: {
616     static const char *g_armv5_compatible_archs[] = {
617         "armv5", "armv4", "arm", "thumbv5", "thumbv4t", "thumb",
618     };
619     return {g_armv5_compatible_archs};
620   }
621   case ArchSpec::eCore_arm_armv4: {
622     static const char *g_armv4_compatible_archs[] = {
623         "armv4",
624         "arm",
625         "thumbv4t",
626         "thumb",
627     };
628     return {g_armv4_compatible_archs};
629   }
630   }
631   return {};
632 }
633 
634 const char *PlatformDarwin::GetCompatibleArch(ArchSpec::Core core, size_t idx) {
635   llvm::ArrayRef<const char *> compatible_archs = GetCompatibleArchs(core);
636   if (!compatible_archs.data())
637     return nullptr;
638   if (idx < compatible_archs.size())
639     return compatible_archs[idx];
640   return nullptr;
641 }
642 
643 /// The architecture selection rules for arm processors These cpu subtypes have
644 /// distinct names (e.g. armv7f) but armv7 binaries run fine on an armv7f
645 /// processor.
646 void PlatformDarwin::ARMGetSupportedArchitectures(
647     std::vector<ArchSpec> &archs) {
648   const ArchSpec system_arch = GetSystemArchitecture();
649   const ArchSpec::Core system_core = system_arch.GetCore();
650 
651   const char *compatible_arch;
652   for (unsigned idx = 0;
653        (compatible_arch = GetCompatibleArch(system_core, idx)); ++idx) {
654     llvm::Triple triple;
655     triple.setArchName(compatible_arch);
656     triple.setVendor(llvm::Triple::VendorType::Apple);
657     archs.push_back(ArchSpec(triple));
658   }
659 }
660 
661 static FileSpec GetXcodeSelectPath() {
662   static FileSpec g_xcode_select_filespec;
663 
664   if (!g_xcode_select_filespec) {
665     FileSpec xcode_select_cmd("/usr/bin/xcode-select");
666     if (FileSystem::Instance().Exists(xcode_select_cmd)) {
667       int exit_status = -1;
668       int signo = -1;
669       std::string command_output;
670       Status status =
671           Host::RunShellCommand("/usr/bin/xcode-select --print-path",
672                                 FileSpec(), // current working directory
673                                 &exit_status, &signo, &command_output,
674                                 std::chrono::seconds(2), // short timeout
675                                 false);                  // don't run in a shell
676       if (status.Success() && exit_status == 0 && !command_output.empty()) {
677         size_t first_non_newline = command_output.find_last_not_of("\r\n");
678         if (first_non_newline != std::string::npos) {
679           command_output.erase(first_non_newline + 1);
680         }
681         g_xcode_select_filespec = FileSpec(command_output);
682       }
683     }
684   }
685 
686   return g_xcode_select_filespec;
687 }
688 
689 BreakpointSP PlatformDarwin::SetThreadCreationBreakpoint(Target &target) {
690   BreakpointSP bp_sp;
691   static const char *g_bp_names[] = {
692       "start_wqthread", "_pthread_wqthread", "_pthread_start",
693   };
694 
695   static const char *g_bp_modules[] = {"libsystem_c.dylib",
696                                        "libSystem.B.dylib"};
697 
698   FileSpecList bp_modules;
699   for (size_t i = 0; i < llvm::array_lengthof(g_bp_modules); i++) {
700     const char *bp_module = g_bp_modules[i];
701     bp_modules.EmplaceBack(bp_module);
702   }
703 
704   bool internal = true;
705   bool hardware = false;
706   LazyBool skip_prologue = eLazyBoolNo;
707   bp_sp = target.CreateBreakpoint(&bp_modules, nullptr, g_bp_names,
708                                   llvm::array_lengthof(g_bp_names),
709                                   eFunctionNameTypeFull, eLanguageTypeUnknown,
710                                   0, skip_prologue, internal, hardware);
711   bp_sp->SetBreakpointKind("thread-creation");
712 
713   return bp_sp;
714 }
715 
716 uint32_t
717 PlatformDarwin::GetResumeCountForLaunchInfo(ProcessLaunchInfo &launch_info) {
718   const FileSpec &shell = launch_info.GetShell();
719   if (!shell)
720     return 1;
721 
722   std::string shell_string = shell.GetPath();
723   const char *shell_name = strrchr(shell_string.c_str(), '/');
724   if (shell_name == nullptr)
725     shell_name = shell_string.c_str();
726   else
727     shell_name++;
728 
729   if (strcmp(shell_name, "sh") == 0) {
730     // /bin/sh re-exec's itself as /bin/bash requiring another resume. But it
731     // only does this if the COMMAND_MODE environment variable is set to
732     // "legacy".
733     if (launch_info.GetEnvironment().lookup("COMMAND_MODE") == "legacy")
734       return 2;
735     return 1;
736   } else if (strcmp(shell_name, "csh") == 0 ||
737              strcmp(shell_name, "tcsh") == 0 ||
738              strcmp(shell_name, "zsh") == 0) {
739     // csh and tcsh always seem to re-exec themselves.
740     return 2;
741   } else
742     return 1;
743 }
744 
745 lldb::ProcessSP PlatformDarwin::DebugProcess(ProcessLaunchInfo &launch_info,
746                                              Debugger &debugger, Target &target,
747                                              Status &error) {
748   ProcessSP process_sp;
749 
750   if (IsHost()) {
751     // We are going to hand this process off to debugserver which will be in
752     // charge of setting the exit status.  However, we still need to reap it
753     // from lldb. So, make sure we use a exit callback which does not set exit
754     // status.
755     const bool monitor_signals = false;
756     launch_info.SetMonitorProcessCallback(
757         &ProcessLaunchInfo::NoOpMonitorCallback, monitor_signals);
758     process_sp = Platform::DebugProcess(launch_info, debugger, target, error);
759   } else {
760     if (m_remote_platform_sp)
761       process_sp = m_remote_platform_sp->DebugProcess(launch_info, debugger,
762                                                       target, error);
763     else
764       error.SetErrorString("the platform is not currently connected");
765   }
766   return process_sp;
767 }
768 
769 void PlatformDarwin::CalculateTrapHandlerSymbolNames() {
770   m_trap_handlers.push_back(ConstString("_sigtramp"));
771 }
772 
773 static FileSpec GetCommandLineToolsLibraryPath() {
774   static FileSpec g_command_line_tools_filespec;
775 
776   if (!g_command_line_tools_filespec) {
777     FileSpec command_line_tools_path(GetXcodeSelectPath());
778     command_line_tools_path.AppendPathComponent("Library");
779     if (FileSystem::Instance().Exists(command_line_tools_path)) {
780       g_command_line_tools_filespec = command_line_tools_path;
781     }
782   }
783 
784   return g_command_line_tools_filespec;
785 }
786 
787 FileSystem::EnumerateDirectoryResult PlatformDarwin::DirectoryEnumerator(
788     void *baton, llvm::sys::fs::file_type file_type, llvm::StringRef path) {
789   SDKEnumeratorInfo *enumerator_info = static_cast<SDKEnumeratorInfo *>(baton);
790 
791   FileSpec spec(path);
792   if (XcodeSDK::SDKSupportsModules(enumerator_info->sdk_type, spec)) {
793     enumerator_info->found_path = spec;
794     return FileSystem::EnumerateDirectoryResult::eEnumerateDirectoryResultNext;
795   }
796 
797   return FileSystem::EnumerateDirectoryResult::eEnumerateDirectoryResultNext;
798 }
799 
800 FileSpec PlatformDarwin::FindSDKInXcodeForModules(XcodeSDK::Type sdk_type,
801                                                   const FileSpec &sdks_spec) {
802   // Look inside Xcode for the required installed iOS SDK version
803 
804   if (!FileSystem::Instance().IsDirectory(sdks_spec)) {
805     return FileSpec();
806   }
807 
808   const bool find_directories = true;
809   const bool find_files = false;
810   const bool find_other = true; // include symlinks
811 
812   SDKEnumeratorInfo enumerator_info;
813 
814   enumerator_info.sdk_type = sdk_type;
815 
816   FileSystem::Instance().EnumerateDirectory(
817       sdks_spec.GetPath(), find_directories, find_files, find_other,
818       DirectoryEnumerator, &enumerator_info);
819 
820   if (FileSystem::Instance().IsDirectory(enumerator_info.found_path))
821     return enumerator_info.found_path;
822   else
823     return FileSpec();
824 }
825 
826 FileSpec PlatformDarwin::GetSDKDirectoryForModules(XcodeSDK::Type sdk_type) {
827   FileSpec sdks_spec = HostInfo::GetXcodeContentsDirectory();
828   sdks_spec.AppendPathComponent("Developer");
829   sdks_spec.AppendPathComponent("Platforms");
830 
831   switch (sdk_type) {
832   case XcodeSDK::Type::MacOSX:
833     sdks_spec.AppendPathComponent("MacOSX.platform");
834     break;
835   case XcodeSDK::Type::iPhoneSimulator:
836     sdks_spec.AppendPathComponent("iPhoneSimulator.platform");
837     break;
838   case XcodeSDK::Type::iPhoneOS:
839     sdks_spec.AppendPathComponent("iPhoneOS.platform");
840     break;
841   case XcodeSDK::Type::WatchSimulator:
842     sdks_spec.AppendPathComponent("WatchSimulator.platform");
843     break;
844   case XcodeSDK::Type::AppleTVSimulator:
845     sdks_spec.AppendPathComponent("AppleTVSimulator.platform");
846     break;
847   default:
848     llvm_unreachable("unsupported sdk");
849   }
850 
851   sdks_spec.AppendPathComponent("Developer");
852   sdks_spec.AppendPathComponent("SDKs");
853 
854   if (sdk_type == XcodeSDK::Type::MacOSX) {
855     llvm::VersionTuple version = HostInfo::GetOSVersion();
856 
857     if (!version.empty()) {
858       if (XcodeSDK::SDKSupportsModules(XcodeSDK::Type::MacOSX, version)) {
859         // If the Xcode SDKs are not available then try to use the
860         // Command Line Tools one which is only for MacOSX.
861         if (!FileSystem::Instance().Exists(sdks_spec)) {
862           sdks_spec = GetCommandLineToolsLibraryPath();
863           sdks_spec.AppendPathComponent("SDKs");
864         }
865 
866         // We slightly prefer the exact SDK for this machine.  See if it is
867         // there.
868 
869         FileSpec native_sdk_spec = sdks_spec;
870         StreamString native_sdk_name;
871         native_sdk_name.Printf("MacOSX%u.%u.sdk", version.getMajor(),
872                                version.getMinor().getValueOr(0));
873         native_sdk_spec.AppendPathComponent(native_sdk_name.GetString());
874 
875         if (FileSystem::Instance().Exists(native_sdk_spec)) {
876           return native_sdk_spec;
877         }
878       }
879     }
880   }
881 
882   return FindSDKInXcodeForModules(sdk_type, sdks_spec);
883 }
884 
885 std::tuple<llvm::VersionTuple, llvm::StringRef>
886 PlatformDarwin::ParseVersionBuildDir(llvm::StringRef dir) {
887   llvm::StringRef build;
888   llvm::StringRef version_str;
889   llvm::StringRef build_str;
890   std::tie(version_str, build_str) = dir.split(' ');
891   llvm::VersionTuple version;
892   if (!version.tryParse(version_str) ||
893       build_str.empty()) {
894     if (build_str.consume_front("(")) {
895       size_t pos = build_str.find(')');
896       build = build_str.slice(0, pos);
897     }
898   }
899 
900   return std::make_tuple(version, build);
901 }
902 
903 llvm::Expected<StructuredData::DictionarySP>
904 PlatformDarwin::FetchExtendedCrashInformation(Process &process) {
905   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
906 
907   StructuredData::ArraySP annotations = ExtractCrashInfoAnnotations(process);
908 
909   if (!annotations || !annotations->GetSize()) {
910     LLDB_LOG(log, "Couldn't extract crash information annotations");
911     return nullptr;
912   }
913 
914   StructuredData::DictionarySP extended_crash_info =
915       std::make_shared<StructuredData::Dictionary>();
916 
917   extended_crash_info->AddItem("crash-info annotations", annotations);
918 
919   return extended_crash_info;
920 }
921 
922 StructuredData::ArraySP
923 PlatformDarwin::ExtractCrashInfoAnnotations(Process &process) {
924   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
925 
926   ConstString section_name("__crash_info");
927   Target &target = process.GetTarget();
928   StructuredData::ArraySP array_sp = std::make_shared<StructuredData::Array>();
929 
930   for (ModuleSP module : target.GetImages().Modules()) {
931     SectionList *sections = module->GetSectionList();
932 
933     std::string module_name = module->GetSpecificationDescription();
934 
935     // The DYDL module is skipped since it's always loaded when running the
936     // binary.
937     if (module_name == "/usr/lib/dyld")
938       continue;
939 
940     if (!sections) {
941       LLDB_LOG(log, "Module {0} doesn't have any section!", module_name);
942       continue;
943     }
944 
945     SectionSP crash_info = sections->FindSectionByName(section_name);
946     if (!crash_info) {
947       LLDB_LOG(log, "Module {0} doesn't have section {1}!", module_name,
948                section_name);
949       continue;
950     }
951 
952     addr_t load_addr = crash_info->GetLoadBaseAddress(&target);
953 
954     if (load_addr == LLDB_INVALID_ADDRESS) {
955       LLDB_LOG(log, "Module {0} has an invalid '{1}' section load address: {2}",
956                module_name, section_name, load_addr);
957       continue;
958     }
959 
960     Status error;
961     CrashInfoAnnotations annotations;
962     size_t expected_size = sizeof(CrashInfoAnnotations);
963     size_t bytes_read = process.ReadMemoryFromInferior(load_addr, &annotations,
964                                                        expected_size, error);
965 
966     if (expected_size != bytes_read || error.Fail()) {
967       LLDB_LOG(log, "Failed to read {0} section from memory in module {1}: {2}",
968                section_name, module_name, error);
969       continue;
970     }
971 
972     // initial support added for version 5
973     if (annotations.version < 5) {
974       LLDB_LOG(log,
975                "Annotation version lower than 5 unsupported! Module {0} has "
976                "version {1} instead.",
977                module_name, annotations.version);
978       continue;
979     }
980 
981     if (!annotations.message) {
982       LLDB_LOG(log, "No message available for module {0}.", module_name);
983       continue;
984     }
985 
986     std::string message;
987     bytes_read =
988         process.ReadCStringFromMemory(annotations.message, message, error);
989 
990     if (message.empty() || bytes_read != message.size() || error.Fail()) {
991       LLDB_LOG(log, "Failed to read the message from memory in module {0}: {1}",
992                module_name, error);
993       continue;
994     }
995 
996     // Remove trailing newline from message
997     if (message.back() == '\n')
998       message.pop_back();
999 
1000     if (!annotations.message2)
1001       LLDB_LOG(log, "No message2 available for module {0}.", module_name);
1002 
1003     std::string message2;
1004     bytes_read =
1005         process.ReadCStringFromMemory(annotations.message2, message2, error);
1006 
1007     if (!message2.empty() && bytes_read == message2.size() && error.Success())
1008       if (message2.back() == '\n')
1009         message2.pop_back();
1010 
1011     StructuredData::DictionarySP entry_sp =
1012         std::make_shared<StructuredData::Dictionary>();
1013 
1014     entry_sp->AddStringItem("image", module->GetFileSpec().GetPath(false));
1015     entry_sp->AddStringItem("uuid", module->GetUUID().GetAsString());
1016     entry_sp->AddStringItem("message", message);
1017     entry_sp->AddStringItem("message2", message2);
1018     entry_sp->AddIntegerItem("abort-cause", annotations.abort_cause);
1019 
1020     array_sp->AddItem(entry_sp);
1021   }
1022 
1023   return array_sp;
1024 }
1025 
1026 void PlatformDarwin::AddClangModuleCompilationOptionsForSDKType(
1027     Target *target, std::vector<std::string> &options, XcodeSDK::Type sdk_type) {
1028   const std::vector<std::string> apple_arguments = {
1029       "-x",       "objective-c++", "-fobjc-arc",
1030       "-fblocks", "-D_ISO646_H",   "-D__ISO646_H",
1031       "-fgnuc-version=4.2.1"};
1032 
1033   options.insert(options.end(), apple_arguments.begin(), apple_arguments.end());
1034 
1035   StreamString minimum_version_option;
1036   bool use_current_os_version = false;
1037   // If the SDK type is for the host OS, use its version number.
1038   auto get_host_os = []() { return HostInfo::GetTargetTriple().getOS(); };
1039   switch (sdk_type) {
1040   case XcodeSDK::Type::MacOSX:
1041     use_current_os_version = get_host_os() == llvm::Triple::MacOSX;
1042     break;
1043   case XcodeSDK::Type::iPhoneOS:
1044     use_current_os_version = get_host_os() == llvm::Triple::IOS;
1045     break;
1046   case XcodeSDK::Type::AppleTVOS:
1047     use_current_os_version = get_host_os() == llvm::Triple::TvOS;
1048     break;
1049   case XcodeSDK::Type::watchOS:
1050     use_current_os_version = get_host_os() == llvm::Triple::WatchOS;
1051     break;
1052   default:
1053     break;
1054   }
1055 
1056   llvm::VersionTuple version;
1057   if (use_current_os_version)
1058     version = GetOSVersion();
1059   else if (target) {
1060     // Our OS doesn't match our executable so we need to get the min OS version
1061     // from the object file
1062     ModuleSP exe_module_sp = target->GetExecutableModule();
1063     if (exe_module_sp) {
1064       ObjectFile *object_file = exe_module_sp->GetObjectFile();
1065       if (object_file)
1066         version = object_file->GetMinimumOSVersion();
1067     }
1068   }
1069   // Only add the version-min options if we got a version from somewhere
1070   if (!version.empty() && sdk_type != XcodeSDK::Type::Linux) {
1071 #define OPTION(PREFIX, NAME, VAR, ...)                                         \
1072   const char *opt_##VAR = NAME;                                                \
1073   (void)opt_##VAR;
1074 #include "clang/Driver/Options.inc"
1075 #undef OPTION
1076     minimum_version_option << '-';
1077     switch (sdk_type) {
1078     case XcodeSDK::Type::MacOSX:
1079       minimum_version_option << opt_mmacosx_version_min_EQ;
1080       break;
1081     case XcodeSDK::Type::iPhoneSimulator:
1082       minimum_version_option << opt_mios_simulator_version_min_EQ;
1083       break;
1084     case XcodeSDK::Type::iPhoneOS:
1085       minimum_version_option << opt_mios_version_min_EQ;
1086       break;
1087     case XcodeSDK::Type::AppleTVSimulator:
1088       minimum_version_option << opt_mtvos_simulator_version_min_EQ;
1089       break;
1090     case XcodeSDK::Type::AppleTVOS:
1091       minimum_version_option << opt_mtvos_version_min_EQ;
1092       break;
1093     case XcodeSDK::Type::WatchSimulator:
1094       minimum_version_option << opt_mwatchos_simulator_version_min_EQ;
1095       break;
1096     case XcodeSDK::Type::watchOS:
1097       minimum_version_option << opt_mwatchos_version_min_EQ;
1098       break;
1099     case XcodeSDK::Type::bridgeOS:
1100     case XcodeSDK::Type::Linux:
1101     case XcodeSDK::Type::unknown:
1102       if (lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST)) {
1103         XcodeSDK::Info info;
1104         info.type = sdk_type;
1105         LLDB_LOGF(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST),
1106                   "Clang modules on %s are not supported",
1107                   XcodeSDK::GetCanonicalName(info).c_str());
1108       }
1109       return;
1110     }
1111     minimum_version_option << version.getAsString();
1112     options.emplace_back(std::string(minimum_version_option.GetString()));
1113   }
1114 
1115   FileSpec sysroot_spec;
1116   // Scope for mutex locker below
1117   {
1118     std::lock_guard<std::mutex> guard(m_mutex);
1119     sysroot_spec = GetSDKDirectoryForModules(sdk_type);
1120   }
1121 
1122   if (FileSystem::Instance().IsDirectory(sysroot_spec.GetPath())) {
1123     options.push_back("-isysroot");
1124     options.push_back(sysroot_spec.GetPath());
1125   }
1126 }
1127 
1128 ConstString PlatformDarwin::GetFullNameForDylib(ConstString basename) {
1129   if (basename.IsEmpty())
1130     return basename;
1131 
1132   StreamString stream;
1133   stream.Printf("lib%s.dylib", basename.GetCString());
1134   return ConstString(stream.GetString());
1135 }
1136 
1137 llvm::VersionTuple PlatformDarwin::GetOSVersion(Process *process) {
1138   if (process && GetPluginName().contains("-simulator")) {
1139     lldb_private::ProcessInstanceInfo proc_info;
1140     if (Host::GetProcessInfo(process->GetID(), proc_info)) {
1141       const Environment &env = proc_info.GetEnvironment();
1142 
1143       llvm::VersionTuple result;
1144       if (!result.tryParse(env.lookup("SIMULATOR_RUNTIME_VERSION")))
1145         return result;
1146 
1147       std::string dyld_root_path = env.lookup("DYLD_ROOT_PATH");
1148       if (!dyld_root_path.empty()) {
1149         dyld_root_path += "/System/Library/CoreServices/SystemVersion.plist";
1150         ApplePropertyList system_version_plist(dyld_root_path.c_str());
1151         std::string product_version;
1152         if (system_version_plist.GetValueAsString("ProductVersion",
1153                                                   product_version)) {
1154           if (!result.tryParse(product_version))
1155             return result;
1156         }
1157       }
1158     }
1159     // For simulator platforms, do NOT call back through
1160     // Platform::GetOSVersion() as it might call Process::GetHostOSVersion()
1161     // which we don't want as it will be incorrect
1162     return llvm::VersionTuple();
1163   }
1164 
1165   return Platform::GetOSVersion(process);
1166 }
1167 
1168 lldb_private::FileSpec PlatformDarwin::LocateExecutable(const char *basename) {
1169   // A collection of SBFileSpec whose SBFileSpec.m_directory members are filled
1170   // in with any executable directories that should be searched.
1171   static std::vector<FileSpec> g_executable_dirs;
1172 
1173   // Find the global list of directories that we will search for executables
1174   // once so we don't keep doing the work over and over.
1175   static llvm::once_flag g_once_flag;
1176   llvm::call_once(g_once_flag, []() {
1177 
1178     // When locating executables, trust the DEVELOPER_DIR first if it is set
1179     FileSpec xcode_contents_dir = HostInfo::GetXcodeContentsDirectory();
1180     if (xcode_contents_dir) {
1181       FileSpec xcode_lldb_resources = xcode_contents_dir;
1182       xcode_lldb_resources.AppendPathComponent("SharedFrameworks");
1183       xcode_lldb_resources.AppendPathComponent("LLDB.framework");
1184       xcode_lldb_resources.AppendPathComponent("Resources");
1185       if (FileSystem::Instance().Exists(xcode_lldb_resources)) {
1186         FileSpec dir;
1187         dir.GetDirectory().SetCString(xcode_lldb_resources.GetPath().c_str());
1188         g_executable_dirs.push_back(dir);
1189       }
1190     }
1191     // Xcode might not be installed so we also check for the Command Line Tools.
1192     FileSpec command_line_tools_dir = GetCommandLineToolsLibraryPath();
1193     if (command_line_tools_dir) {
1194       FileSpec cmd_line_lldb_resources = command_line_tools_dir;
1195       cmd_line_lldb_resources.AppendPathComponent("PrivateFrameworks");
1196       cmd_line_lldb_resources.AppendPathComponent("LLDB.framework");
1197       cmd_line_lldb_resources.AppendPathComponent("Resources");
1198       if (FileSystem::Instance().Exists(cmd_line_lldb_resources)) {
1199         FileSpec dir;
1200         dir.GetDirectory().SetCString(
1201             cmd_line_lldb_resources.GetPath().c_str());
1202         g_executable_dirs.push_back(dir);
1203       }
1204     }
1205   });
1206 
1207   // Now search the global list of executable directories for the executable we
1208   // are looking for
1209   for (const auto &executable_dir : g_executable_dirs) {
1210     FileSpec executable_file;
1211     executable_file.GetDirectory() = executable_dir.GetDirectory();
1212     executable_file.GetFilename().SetCString(basename);
1213     if (FileSystem::Instance().Exists(executable_file))
1214       return executable_file;
1215   }
1216 
1217   return FileSpec();
1218 }
1219 
1220 lldb_private::Status
1221 PlatformDarwin::LaunchProcess(lldb_private::ProcessLaunchInfo &launch_info) {
1222   // Starting in Fall 2016 OSes, NSLog messages only get mirrored to stderr if
1223   // the OS_ACTIVITY_DT_MODE environment variable is set.  (It doesn't require
1224   // any specific value; rather, it just needs to exist). We will set it here
1225   // as long as the IDE_DISABLED_OS_ACTIVITY_DT_MODE flag is not set.  Xcode
1226   // makes use of IDE_DISABLED_OS_ACTIVITY_DT_MODE to tell
1227   // LLDB *not* to muck with the OS_ACTIVITY_DT_MODE flag when they
1228   // specifically want it unset.
1229   const char *disable_env_var = "IDE_DISABLED_OS_ACTIVITY_DT_MODE";
1230   auto &env_vars = launch_info.GetEnvironment();
1231   if (!env_vars.count(disable_env_var)) {
1232     // We want to make sure that OS_ACTIVITY_DT_MODE is set so that we get
1233     // os_log and NSLog messages mirrored to the target process stderr.
1234     env_vars.try_emplace("OS_ACTIVITY_DT_MODE", "enable");
1235   }
1236 
1237   // Let our parent class do the real launching.
1238   return PlatformPOSIX::LaunchProcess(launch_info);
1239 }
1240 
1241 lldb_private::Status PlatformDarwin::FindBundleBinaryInExecSearchPaths(
1242     const ModuleSpec &module_spec, Process *process, ModuleSP &module_sp,
1243     const FileSpecList *module_search_paths_ptr,
1244     llvm::SmallVectorImpl<ModuleSP> *old_modules, bool *did_create_ptr) {
1245   const FileSpec &platform_file = module_spec.GetFileSpec();
1246   // See if the file is present in any of the module_search_paths_ptr
1247   // directories.
1248   if (!module_sp && module_search_paths_ptr && platform_file) {
1249     // create a vector of all the file / directory names in platform_file e.g.
1250     // this might be
1251     // /System/Library/PrivateFrameworks/UIFoundation.framework/UIFoundation
1252     //
1253     // We'll need to look in the module_search_paths_ptr directories for both
1254     // "UIFoundation" and "UIFoundation.framework" -- most likely the latter
1255     // will be the one we find there.
1256 
1257     FileSpec platform_pull_upart(platform_file);
1258     std::vector<std::string> path_parts;
1259     path_parts.push_back(
1260         platform_pull_upart.GetLastPathComponent().AsCString());
1261     while (platform_pull_upart.RemoveLastPathComponent()) {
1262       ConstString part = platform_pull_upart.GetLastPathComponent();
1263       path_parts.push_back(part.AsCString());
1264     }
1265     const size_t path_parts_size = path_parts.size();
1266 
1267     size_t num_module_search_paths = module_search_paths_ptr->GetSize();
1268     for (size_t i = 0; i < num_module_search_paths; ++i) {
1269       Log *log_verbose = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST);
1270       LLDB_LOGF(
1271           log_verbose,
1272           "PlatformRemoteDarwinDevice::GetSharedModule searching for binary in "
1273           "search-path %s",
1274           module_search_paths_ptr->GetFileSpecAtIndex(i).GetPath().c_str());
1275       // Create a new FileSpec with this module_search_paths_ptr plus just the
1276       // filename ("UIFoundation"), then the parent dir plus filename
1277       // ("UIFoundation.framework/UIFoundation") etc - up to four names (to
1278       // handle "Foo.framework/Contents/MacOS/Foo")
1279 
1280       for (size_t j = 0; j < 4 && j < path_parts_size - 1; ++j) {
1281         FileSpec path_to_try(module_search_paths_ptr->GetFileSpecAtIndex(i));
1282 
1283         // Add the components backwards.  For
1284         // .../PrivateFrameworks/UIFoundation.framework/UIFoundation path_parts
1285         // is
1286         //   [0] UIFoundation
1287         //   [1] UIFoundation.framework
1288         //   [2] PrivateFrameworks
1289         //
1290         // and if 'j' is 2, we want to append path_parts[1] and then
1291         // path_parts[0], aka 'UIFoundation.framework/UIFoundation', to the
1292         // module_search_paths_ptr path.
1293 
1294         for (int k = j; k >= 0; --k) {
1295           path_to_try.AppendPathComponent(path_parts[k]);
1296         }
1297 
1298         if (FileSystem::Instance().Exists(path_to_try)) {
1299           ModuleSpec new_module_spec(module_spec);
1300           new_module_spec.GetFileSpec() = path_to_try;
1301           Status new_error(
1302               Platform::GetSharedModule(new_module_spec, process, module_sp,
1303                                         nullptr, old_modules, did_create_ptr));
1304 
1305           if (module_sp) {
1306             module_sp->SetPlatformFileSpec(path_to_try);
1307             return new_error;
1308           }
1309         }
1310       }
1311     }
1312   }
1313   return Status();
1314 }
1315 
1316 std::string PlatformDarwin::FindComponentInPath(llvm::StringRef path,
1317                                                 llvm::StringRef component) {
1318   auto begin = llvm::sys::path::begin(path);
1319   auto end = llvm::sys::path::end(path);
1320   for (auto it = begin; it != end; ++it) {
1321     if (it->contains(component)) {
1322       llvm::SmallString<128> buffer;
1323       llvm::sys::path::append(buffer, begin, ++it,
1324                               llvm::sys::path::Style::posix);
1325       return buffer.str().str();
1326     }
1327   }
1328   return {};
1329 }
1330 
1331 FileSpec PlatformDarwin::GetCurrentToolchainDirectory() {
1332   if (FileSpec fspec = HostInfo::GetShlibDir())
1333     return FileSpec(FindComponentInPath(fspec.GetPath(), ".xctoolchain"));
1334   return {};
1335 }
1336 
1337 FileSpec PlatformDarwin::GetCurrentCommandLineToolsDirectory() {
1338   if (FileSpec fspec = HostInfo::GetShlibDir())
1339     return FileSpec(FindComponentInPath(fspec.GetPath(), "CommandLineTools"));
1340   return {};
1341 }
1342