lldb/source/Plugins/SymbolVendor/ELF/SymbolVendorELF.cpp

   1 //===-- SymbolVendorELF.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 "SymbolVendorELF.h"
  10
  11 #include <cstring>
  12
  13 #include "Plugins/ObjectFile/ELF/ObjectFileELF.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/Symbol/LocateSymbolFile.h"
  20 #include "lldb/Symbol/ObjectFile.h"
  21 #include "lldb/Target/Target.h"
  22 #include "lldb/Utility/StreamString.h"
  23 #include "lldb/Utility/Timer.h"
  24
  25 using namespace lldb;
  26 using namespace lldb_private;
  27
  28 LLDB_PLUGIN_DEFINE(SymbolVendorELF)
  29
  30 // SymbolVendorELF constructor
  31 SymbolVendorELF::SymbolVendorELF(const lldb::ModuleSP &module_sp)
  32     : SymbolVendor(module_sp) {}
  33
  34 void SymbolVendorELF::Initialize() {
  35   PluginManager::RegisterPlugin(GetPluginNameStatic(),
  36                                 GetPluginDescriptionStatic(), CreateInstance);
  37 }
  38
  39 void SymbolVendorELF::Terminate() {
  40   PluginManager::UnregisterPlugin(CreateInstance);
  41 }
  42
  43 llvm::StringRef SymbolVendorELF::GetPluginDescriptionStatic() {
  44   return "Symbol vendor for ELF that looks for dSYM files that match "
  45          "executables.";
  46 }
  47
  48 // CreateInstance
  49 //
  50 // Platforms can register a callback to use when creating symbol vendors to
  51 // allow for complex debug information file setups, and to also allow for
  52 // finding separate debug information files.
  53 SymbolVendor *
  54 SymbolVendorELF::CreateInstance(const lldb::ModuleSP &module_sp,
  55                                 lldb_private::Stream *feedback_strm) {
  56   if (!module_sp)
  57     return nullptr;
  58
  59   ObjectFileELF *obj_file =
  60       llvm::dyn_cast_or_null<ObjectFileELF>(module_sp->GetObjectFile());
  61   if (!obj_file)
  62     return nullptr;
  63
  64   lldb_private::UUID uuid = obj_file->GetUUID();
  65   if (!uuid)
  66     return nullptr;
  67
  68   // If the main object file already contains debug info, then we are done.
  69   if (obj_file->GetSectionList()->FindSectionByType(
  70           lldb::eSectionTypeDWARFDebugInfo, true))
  71     return nullptr;
  72
  73   // If the module specified a filespec, use that.
  74   FileSpec fspec = module_sp->GetSymbolFileFileSpec();
  75   // Otherwise, try gnu_debuglink, if one exists.
  76   if (!fspec)
  77     fspec = obj_file->GetDebugLink().value_or(FileSpec());
  78
  79   LLDB_SCOPED_TIMERF("SymbolVendorELF::CreateInstance (module = %s)",
  80                      module_sp->GetFileSpec().GetPath().c_str());
  81
  82   ModuleSpec module_spec;
  83
  84   module_spec.GetFileSpec() = obj_file->GetFileSpec();
  85   FileSystem::Instance().Resolve(module_spec.GetFileSpec());
  86   module_spec.GetSymbolFileSpec() = fspec;
  87   module_spec.GetUUID() = uuid;
  88   FileSpecList search_paths = Target::GetDefaultDebugFileSearchPaths();
  89   FileSpec dsym_fspec =
  90       Symbols::LocateExecutableSymbolFile(module_spec, search_paths);
  91   if (!dsym_fspec)
  92     return nullptr;
  93
  94   DataBufferSP dsym_file_data_sp;
  95   lldb::offset_t dsym_file_data_offset = 0;
  96   ObjectFileSP dsym_objfile_sp = ObjectFile::FindPlugin(
  97       module_sp, &dsym_fspec, 0, FileSystem::Instance().GetByteSize(dsym_fspec),
  98       dsym_file_data_sp, dsym_file_data_offset);
  99   if (!dsym_objfile_sp)
 100     return nullptr;
 101
 102   // This objfile is for debugging purposes. Sadly, ObjectFileELF won't
 103   // be able to figure this out consistently as the symbol file may not
 104   // have stripped the code sections, etc.
 105   dsym_objfile_sp->SetType(ObjectFile::eTypeDebugInfo);
 106
 107   SymbolVendorELF *symbol_vendor = new SymbolVendorELF(module_sp);
 108
 109   // Get the module unified section list and add our debug sections to
 110   // that.
 111   SectionList *module_section_list = module_sp->GetSectionList();
 112   SectionList *objfile_section_list = dsym_objfile_sp->GetSectionList();
 113
 114   if (!module_section_list || !objfile_section_list)
 115     return nullptr;
 116
 117   static const SectionType g_sections[] = {
 118       eSectionTypeDWARFDebugAbbrev,     eSectionTypeDWARFDebugAddr,
 119       eSectionTypeDWARFDebugAranges,    eSectionTypeDWARFDebugCuIndex,
 120       eSectionTypeDWARFDebugFrame,      eSectionTypeDWARFDebugInfo,
 121       eSectionTypeDWARFDebugLine,       eSectionTypeDWARFDebugLineStr,
 122       eSectionTypeDWARFDebugLoc,        eSectionTypeDWARFDebugLocLists,
 123       eSectionTypeDWARFDebugMacInfo,    eSectionTypeDWARFDebugMacro,
 124       eSectionTypeDWARFDebugNames,      eSectionTypeDWARFDebugPubNames,
 125       eSectionTypeDWARFDebugPubTypes,   eSectionTypeDWARFDebugRanges,
 126       eSectionTypeDWARFDebugRngLists,   eSectionTypeDWARFDebugStr,
 127       eSectionTypeDWARFDebugStrOffsets, eSectionTypeDWARFDebugTypes,
 128       eSectionTypeELFSymbolTable,       eSectionTypeDWARFGNUDebugAltLink,
 129   };
 130   for (SectionType section_type : g_sections) {
 131     if (SectionSP section_sp =
 132             objfile_section_list->FindSectionByType(section_type, true)) {
 133       if (SectionSP module_section_sp =
 134               module_section_list->FindSectionByType(section_type, true))
 135         module_section_list->ReplaceSection(module_section_sp->GetID(),
 136                                             section_sp);
 137       else
 138         module_section_list->AddSection(section_sp);
 139     }
 140   }
 141
 142   symbol_vendor->AddSymbolFileRepresentation(dsym_objfile_sp);
 143   return symbol_vendor;
 144 }