aboutsummaryrefslogtreecommitdiff
path: root/lldb/source/Plugins/SymbolLocator/Default/SymbolLocatorDefault.cpp
blob: ed014f99fdb5e79116617f15a778645f088be018 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
//===-- SymbolLocatorDefault.cpp ------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "SymbolLocatorDefault.h"

#include <cstring>
#include <optional>

#include "Plugins/ObjectFile/wasm/ObjectFileWasm.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleList.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Core/Progress.h"
#include "lldb/Core/Section.h"
#include "lldb/Host/FileSystem.h"
#include "lldb/Host/Host.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/ArchSpec.h"
#include "lldb/Utility/DataBuffer.h"
#include "lldb/Utility/DataExtractor.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/StreamString.h"
#include "lldb/Utility/Timer.h"
#include "lldb/Utility/UUID.h"

#include "llvm/ADT/SmallSet.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/ThreadPool.h"

// From MacOSX system header "mach/machine.h"
typedef int cpu_type_t;
typedef int cpu_subtype_t;

using namespace lldb;
using namespace lldb_private;

LLDB_PLUGIN_DEFINE(SymbolLocatorDefault)

SymbolLocatorDefault::SymbolLocatorDefault() : SymbolLocator() {}

void SymbolLocatorDefault::Initialize() {
  PluginManager::RegisterPlugin(
      GetPluginNameStatic(), GetPluginDescriptionStatic(), CreateInstance,
      LocateExecutableObjectFile, LocateExecutableSymbolFile,
      DownloadObjectAndSymbolFile);
}

void SymbolLocatorDefault::Terminate() {
  PluginManager::UnregisterPlugin(CreateInstance);
}

llvm::StringRef SymbolLocatorDefault::GetPluginDescriptionStatic() {
  return "Default symbol locator.";
}

SymbolLocator *SymbolLocatorDefault::CreateInstance() {
  return new SymbolLocatorDefault();
}

std::optional<ModuleSpec> SymbolLocatorDefault::LocateExecutableObjectFile(
    const ModuleSpec &module_spec) {
  const FileSpec &exec_fspec = module_spec.GetFileSpec();
  const ArchSpec *arch = module_spec.GetArchitecturePtr();
  const UUID *uuid = module_spec.GetUUIDPtr();
  LLDB_SCOPED_TIMERF(
      "LocateExecutableObjectFile (file = %s, arch = %s, uuid = %p)",
      exec_fspec ? exec_fspec.GetFilename().AsCString("<NULL>") : "<NULL>",
      arch ? arch->GetArchitectureName() : "<NULL>", (const void *)uuid);

  ModuleSpecList module_specs;
  ModuleSpec matched_module_spec;
  if (exec_fspec &&
      ObjectFile::GetModuleSpecifications(exec_fspec, 0, 0, module_specs) &&
      module_specs.FindMatchingModuleSpec(module_spec, matched_module_spec)) {
    ModuleSpec result;
    result.GetFileSpec() = exec_fspec;
    return result;
  }

  return {};
}

// Keep "symbols.enable-external-lookup" description in sync with this function.
std::optional<FileSpec> SymbolLocatorDefault::LocateExecutableSymbolFile(
    const ModuleSpec &module_spec, const FileSpecList &default_search_paths) {

  FileSpec symbol_file_spec = module_spec.GetSymbolFileSpec();
  if (symbol_file_spec.IsAbsolute() &&
      FileSystem::Instance().Exists(symbol_file_spec))
    return symbol_file_spec;

  Progress progress(llvm::formatv(
      "Locating external symbol file for {0}",
      module_spec.GetFileSpec().GetFilename().AsCString("<Unknown>")));

  FileSpecList debug_file_search_paths = default_search_paths;

  // Add module directory.
  FileSpec module_file_spec = module_spec.GetFileSpec();
  // We keep the unresolved pathname if it fails.
  FileSystem::Instance().ResolveSymbolicLink(module_file_spec,
                                             module_file_spec);

  ConstString file_dir = module_file_spec.GetDirectory();
  {
    FileSpec file_spec(file_dir.AsCString("."));
    FileSystem::Instance().Resolve(file_spec);
    debug_file_search_paths.AppendIfUnique(file_spec);
  }

  if (ModuleList::GetGlobalModuleListProperties().GetEnableExternalLookup()) {

    // Add current working directory.
    {
      FileSpec file_spec(".");
      FileSystem::Instance().Resolve(file_spec);
      debug_file_search_paths.AppendIfUnique(file_spec);
    }

#ifndef _WIN32
#if defined(__NetBSD__)
    // Add /usr/libdata/debug directory.
    {
      FileSpec file_spec("/usr/libdata/debug");
      FileSystem::Instance().Resolve(file_spec);
      debug_file_search_paths.AppendIfUnique(file_spec);
    }
#else
    // Add /usr/lib/debug directory.
    {
      FileSpec file_spec("/usr/lib/debug");
      FileSystem::Instance().Resolve(file_spec);
      debug_file_search_paths.AppendIfUnique(file_spec);
    }
#endif
#endif // _WIN32
  }

  std::string uuid_str;
  const UUID &module_uuid = module_spec.GetUUID();
  if (module_uuid.IsValid()) {
    // Some debug files are stored in the .build-id directory like this:
    //   /usr/lib/debug/.build-id/ff/e7fe727889ad82bb153de2ad065b2189693315.debug
    uuid_str = module_uuid.GetAsString("");
    std::transform(uuid_str.begin(), uuid_str.end(), uuid_str.begin(),
                   ::tolower);
    uuid_str.insert(2, 1, '/');
    uuid_str = uuid_str + ".debug";
  }

  size_t num_directories = debug_file_search_paths.GetSize();
  for (size_t idx = 0; idx < num_directories; ++idx) {
    FileSpec dirspec = debug_file_search_paths.GetFileSpecAtIndex(idx);
    FileSystem::Instance().Resolve(dirspec);
    if (!FileSystem::Instance().IsDirectory(dirspec))
      continue;

    std::vector<std::string> files;
    std::string dirname = dirspec.GetPath();

    if (!uuid_str.empty())
      files.push_back(dirname + "/.build-id/" + uuid_str);
    if (symbol_file_spec.GetFilename()) {
      files.push_back(dirname + "/" +
                      symbol_file_spec.GetFilename().GetCString());
      files.push_back(dirname + "/.debug/" +
                      symbol_file_spec.GetFilename().GetCString());

      // Some debug files may stored in the module directory like this:
      //   /usr/lib/debug/usr/lib/library.so.debug
      if (!file_dir.IsEmpty())
        files.push_back(dirname + file_dir.AsCString() + "/" +
                        symbol_file_spec.GetFilename().GetCString());
    }

    const uint32_t num_files = files.size();
    for (size_t idx_file = 0; idx_file < num_files; ++idx_file) {
      const std::string &filename = files[idx_file];
      FileSpec file_spec(filename);
      FileSystem::Instance().Resolve(file_spec);

      if (llvm::sys::fs::equivalent(file_spec.GetPath(),
                                    module_file_spec.GetPath()))
        continue;

      if (FileSystem::Instance().Exists(file_spec)) {
        lldb_private::ModuleSpecList specs;
        const size_t num_specs =
            ObjectFile::GetModuleSpecifications(file_spec, 0, 0, specs);
        ModuleSpec mspec;
        bool valid_mspec = false;
        if (num_specs == 2) {
          // Special case to handle both i386 and i686 from ObjectFilePECOFF
          ModuleSpec mspec2;
          if (specs.GetModuleSpecAtIndex(0, mspec) &&
              specs.GetModuleSpecAtIndex(1, mspec2) &&
              mspec.GetArchitecture().GetTriple().isCompatibleWith(
                  mspec2.GetArchitecture().GetTriple())) {
            valid_mspec = true;
          }
        }
        if (!valid_mspec) {
          assert(num_specs <= 1 &&
                 "Symbol Vendor supports only a single architecture");
          if (num_specs == 1) {
            if (specs.GetModuleSpecAtIndex(0, mspec)) {
              valid_mspec = true;
            }
          }
        }
        if (valid_mspec) {
          // Skip the uuids check if module_uuid is invalid. For example,
          // this happens for *.dwp files since at the moment llvm-dwp
          // doesn't output build ids, nor does binutils dwp.
          if (!module_uuid.IsValid() || module_uuid == mspec.GetUUID())
            return file_spec;
        }
      }
    }
  }

  return {};
}

bool SymbolLocatorDefault::DownloadObjectAndSymbolFile(ModuleSpec &module_spec,
                                                       Status &error,
                                                       bool force_lookup,
                                                       bool copy_executable) {
  return false;
}