1 //===-- SymbolVendorMacOSX.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 "SymbolVendorMacOSX.h"
10 
11 #include <cstring>
12 
13 #include "Plugins/ObjectFile/Mach-O/ObjectFileMachO.h"
14 #include "lldb/Core/Module.h"
15 #include "lldb/Core/ModuleSpec.h"
16 #include "lldb/Core/PluginManager.h"
17 #include "lldb/Core/Section.h"
18 #include "lldb/Host/Host.h"
19 #include "lldb/Host/XML.h"
20 #include "lldb/Symbol/LocateSymbolFile.h"
21 #include "lldb/Symbol/ObjectFile.h"
22 #include "lldb/Target/Target.h"
23 #include "lldb/Utility/ReproducerProvider.h"
24 #include "lldb/Utility/StreamString.h"
25 #include "lldb/Utility/Timer.h"
26 
27 using namespace lldb;
28 using namespace lldb_private;
29 
LLDB_PLUGIN_DEFINE(SymbolVendorMacOSX)30 LLDB_PLUGIN_DEFINE(SymbolVendorMacOSX)
31 
32 // SymbolVendorMacOSX constructor
33 SymbolVendorMacOSX::SymbolVendorMacOSX(const lldb::ModuleSP &module_sp)
34     : SymbolVendor(module_sp) {}
35 
UUIDsMatch(Module * module,ObjectFile * ofile,lldb_private::Stream * feedback_strm)36 static bool UUIDsMatch(Module *module, ObjectFile *ofile,
37                        lldb_private::Stream *feedback_strm) {
38   if (module && ofile) {
39     // Make sure the UUIDs match
40     lldb_private::UUID dsym_uuid = ofile->GetUUID();
41     if (!dsym_uuid) {
42       if (feedback_strm) {
43         feedback_strm->PutCString(
44             "warning: failed to get the uuid for object file: '");
45         ofile->GetFileSpec().Dump(feedback_strm->AsRawOstream());
46         feedback_strm->PutCString("\n");
47       }
48       return false;
49     }
50 
51     if (dsym_uuid == module->GetUUID())
52       return true;
53 
54     // Emit some warning messages since the UUIDs do not match!
55     if (feedback_strm) {
56       feedback_strm->PutCString(
57           "warning: UUID mismatch detected between modules:\n    ");
58       module->GetUUID().Dump(feedback_strm);
59       feedback_strm->PutChar(' ');
60       module->GetFileSpec().Dump(feedback_strm->AsRawOstream());
61       feedback_strm->PutCString("\n    ");
62       dsym_uuid.Dump(feedback_strm);
63       feedback_strm->PutChar(' ');
64       ofile->GetFileSpec().Dump(feedback_strm->AsRawOstream());
65       feedback_strm->EOL();
66     }
67   }
68   return false;
69 }
70 
Initialize()71 void SymbolVendorMacOSX::Initialize() {
72   PluginManager::RegisterPlugin(GetPluginNameStatic(),
73                                 GetPluginDescriptionStatic(), CreateInstance);
74 }
75 
Terminate()76 void SymbolVendorMacOSX::Terminate() {
77   PluginManager::UnregisterPlugin(CreateInstance);
78 }
79 
GetPluginDescriptionStatic()80 llvm::StringRef SymbolVendorMacOSX::GetPluginDescriptionStatic() {
81   return "Symbol vendor for MacOSX that looks for dSYM files that match "
82          "executables.";
83 }
84 
85 // CreateInstance
86 //
87 // Platforms can register a callback to use when creating symbol vendors to
88 // allow for complex debug information file setups, and to also allow for
89 // finding separate debug information files.
90 SymbolVendor *
CreateInstance(const lldb::ModuleSP & module_sp,lldb_private::Stream * feedback_strm)91 SymbolVendorMacOSX::CreateInstance(const lldb::ModuleSP &module_sp,
92                                    lldb_private::Stream *feedback_strm) {
93   if (!module_sp)
94     return NULL;
95 
96   ObjectFile *obj_file =
97       llvm::dyn_cast_or_null<ObjectFileMachO>(module_sp->GetObjectFile());
98   if (!obj_file)
99     return NULL;
100 
101   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
102   Timer scoped_timer(func_cat,
103                      "SymbolVendorMacOSX::CreateInstance (module = %s)",
104                      module_sp->GetFileSpec().GetPath().c_str());
105   SymbolVendorMacOSX *symbol_vendor = new SymbolVendorMacOSX(module_sp);
106   if (symbol_vendor) {
107     char path[PATH_MAX];
108     path[0] = '\0';
109 
110     // Try and locate the dSYM file on Mac OS X
111     static Timer::Category func_cat2(
112         "SymbolVendorMacOSX::CreateInstance() locate dSYM");
113     Timer scoped_timer2(
114         func_cat2,
115         "SymbolVendorMacOSX::CreateInstance (module = %s) locate dSYM",
116         module_sp->GetFileSpec().GetPath().c_str());
117 
118     // First check to see if the module has a symbol file in mind already. If
119     // it does, then we MUST use that.
120     FileSpec dsym_fspec(module_sp->GetSymbolFileFileSpec());
121 
122     ObjectFileSP dsym_objfile_sp;
123     if (!dsym_fspec) {
124       // No symbol file was specified in the module, lets try and find one
125       // ourselves.
126       FileSpec file_spec = obj_file->GetFileSpec();
127       if (!file_spec)
128         file_spec = module_sp->GetFileSpec();
129 
130       ModuleSpec module_spec(file_spec, module_sp->GetArchitecture());
131       module_spec.GetUUID() = module_sp->GetUUID();
132       FileSpecList search_paths = Target::GetDefaultDebugFileSearchPaths();
133       dsym_fspec =
134           Symbols::LocateExecutableSymbolFile(module_spec, search_paths);
135       if (module_spec.GetSourceMappingList().GetSize())
136         module_sp->GetSourceMappingList().Append(
137             module_spec.GetSourceMappingList(), true);
138     }
139 
140     if (dsym_fspec) {
141       // Compute dSYM root.
142       std::string dsym_root = dsym_fspec.GetPath();
143       const size_t pos = dsym_root.find("/Contents/Resources/");
144       dsym_root = pos != std::string::npos ? dsym_root.substr(0, pos) : "";
145 
146       DataBufferSP dsym_file_data_sp;
147       lldb::offset_t dsym_file_data_offset = 0;
148       dsym_objfile_sp =
149           ObjectFile::FindPlugin(module_sp, &dsym_fspec, 0,
150                                  FileSystem::Instance().GetByteSize(dsym_fspec),
151                                  dsym_file_data_sp, dsym_file_data_offset);
152       // Important to save the dSYM FileSpec so we don't call
153       // Symbols::LocateExecutableSymbolFile a second time while trying to
154       // add the symbol ObjectFile to this Module.
155       if (dsym_objfile_sp && !module_sp->GetSymbolFileFileSpec()) {
156         module_sp->SetSymbolFileFileSpec(dsym_fspec);
157       }
158       if (UUIDsMatch(module_sp.get(), dsym_objfile_sp.get(), feedback_strm)) {
159         // We need a XML parser if we hope to parse a plist...
160         if (XMLDocument::XMLEnabled()) {
161           if (module_sp->GetSourceMappingList().IsEmpty()) {
162             lldb_private::UUID dsym_uuid = dsym_objfile_sp->GetUUID();
163             if (dsym_uuid) {
164               std::string uuid_str = dsym_uuid.GetAsString();
165               if (!uuid_str.empty() && !dsym_root.empty()) {
166                 char dsym_uuid_plist_path[PATH_MAX];
167                 snprintf(dsym_uuid_plist_path, sizeof(dsym_uuid_plist_path),
168                          "%s/Contents/Resources/%s.plist", dsym_root.c_str(),
169                          uuid_str.c_str());
170                 FileSpec dsym_uuid_plist_spec(dsym_uuid_plist_path);
171                 if (FileSystem::Instance().Exists(dsym_uuid_plist_spec)) {
172                   ApplePropertyList plist(dsym_uuid_plist_path);
173                   if (plist) {
174                     std::string DBGBuildSourcePath;
175                     std::string DBGSourcePath;
176 
177                     // DBGSourcePathRemapping is a dictionary in the plist
178                     // with keys which are DBGBuildSourcePath file paths and
179                     // values which are DBGSourcePath file paths
180 
181                     StructuredData::ObjectSP plist_sp =
182                         plist.GetStructuredData();
183                     if (plist_sp.get() && plist_sp->GetAsDictionary() &&
184                         plist_sp->GetAsDictionary()->HasKey(
185                             "DBGSourcePathRemapping") &&
186                         plist_sp->GetAsDictionary()
187                             ->GetValueForKey("DBGSourcePathRemapping")
188                             ->GetAsDictionary()) {
189 
190                       // If DBGVersion 1 or DBGVersion missing, ignore
191                       // DBGSourcePathRemapping. If DBGVersion 2, strip last two
192                       // components of path remappings from
193                       //                  entries to fix an issue with a
194                       //                  specific set of DBGSourcePathRemapping
195                       //                  entries that lldb worked with.
196                       // If DBGVersion 3, trust & use the source path remappings
197                       // as-is.
198                       //
199 
200                       bool new_style_source_remapping_dictionary = false;
201                       bool do_truncate_remapping_names = false;
202                       std::string original_DBGSourcePath_value = DBGSourcePath;
203                       if (plist_sp->GetAsDictionary()->HasKey("DBGVersion")) {
204                         std::string version_string =
205                             std::string(plist_sp->GetAsDictionary()
206                                             ->GetValueForKey("DBGVersion")
207                                             ->GetStringValue(""));
208                         if (!version_string.empty() &&
209                             isdigit(version_string[0])) {
210                           int version_number = atoi(version_string.c_str());
211                           if (version_number > 1) {
212                             new_style_source_remapping_dictionary = true;
213                           }
214                           if (version_number == 2) {
215                             do_truncate_remapping_names = true;
216                           }
217                         }
218                       }
219 
220                       StructuredData::Dictionary *remappings_dict =
221                           plist_sp->GetAsDictionary()
222                               ->GetValueForKey("DBGSourcePathRemapping")
223                               ->GetAsDictionary();
224                       remappings_dict->ForEach(
225                           [&module_sp, new_style_source_remapping_dictionary,
226                            original_DBGSourcePath_value,
227                            do_truncate_remapping_names](
228                               ConstString key,
229                               StructuredData::Object *object) -> bool {
230                             if (object && object->GetAsString()) {
231 
232                               // key is DBGBuildSourcePath
233                               // object is DBGSourcePath
234                               std::string DBGSourcePath =
235                                   std::string(object->GetStringValue());
236                               if (!new_style_source_remapping_dictionary &&
237                                   !original_DBGSourcePath_value.empty()) {
238                                 DBGSourcePath = original_DBGSourcePath_value;
239                               }
240                               module_sp->GetSourceMappingList().Append(
241                                   key.GetStringRef(), DBGSourcePath, true);
242                               // With version 2 of DBGSourcePathRemapping, we
243                               // can chop off the last two filename parts
244                               // from the source remapping and get a more
245                               // general source remapping that still works.
246                               // Add this as another option in addition to
247                               // the full source path remap.
248                               if (do_truncate_remapping_names) {
249                                 FileSpec build_path(key.AsCString());
250                                 FileSpec source_path(DBGSourcePath.c_str());
251                                 build_path.RemoveLastPathComponent();
252                                 build_path.RemoveLastPathComponent();
253                                 source_path.RemoveLastPathComponent();
254                                 source_path.RemoveLastPathComponent();
255                                 module_sp->GetSourceMappingList().Append(
256                                     build_path.GetPath(), source_path.GetPath(),
257                                     true);
258                               }
259                             }
260                             return true;
261                           });
262                     }
263 
264                     // If we have a DBGBuildSourcePath + DBGSourcePath pair,
265                     // append those to the source path remappings.
266 
267                     plist.GetValueAsString("DBGBuildSourcePath",
268                                            DBGBuildSourcePath);
269                     plist.GetValueAsString("DBGSourcePath", DBGSourcePath);
270                     if (!DBGBuildSourcePath.empty() && !DBGSourcePath.empty()) {
271                       module_sp->GetSourceMappingList().Append(
272                           DBGBuildSourcePath, DBGSourcePath, true);
273                     }
274                   }
275                 }
276               }
277             }
278           }
279         }
280 
281         symbol_vendor->AddSymbolFileRepresentation(dsym_objfile_sp);
282         if (!dsym_root.empty()) {
283           if (repro::Generator *g =
284                   repro::Reproducer::Instance().GetGenerator()) {
285             repro::FileProvider &fp = g->GetOrCreate<repro::FileProvider>();
286             fp.RecordInterestingDirectoryRecursive(dsym_root);
287           }
288         }
289         return symbol_vendor;
290       }
291     }
292 
293     // Just create our symbol vendor using the current objfile as this is
294     // either an executable with no dSYM (that we could locate), an executable
295     // with a dSYM that has a UUID that doesn't match.
296     symbol_vendor->AddSymbolFileRepresentation(obj_file->shared_from_this());
297   }
298   return symbol_vendor;
299 }
300