// Copyright (c) 2011 Google Inc. // All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following disclaimer // in the documentation and/or other materials provided with the // distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // dump_symbols-inl.h: implement google_breakpad::WriteSymbolFile: // Find all the debugging info in a file and dump it as a Breakpad symbol file. #ifndef COMMON_PECOFF_DUMP_SYMBOLS_INL_H #define COMMON_PECOFF_DUMP_SYMBOLS_INL_H #include #include #include #include #include #include #ifndef _WIN32 #include #endif #include #include #include #include #include #include #include #include "common/dwarf/bytereader-inl.h" #include "common/dwarf/dwarf2diehandler.h" #include "common/dwarf_cfi_to_module.h" #include "common/dwarf_cu_to_module.h" #include "common/dwarf_line_to_module.h" #include "common/module.h" #include "common/scoped_ptr.h" #ifndef NO_STABS_SUPPORT #include "common/stabs_reader.h" #include "common/stabs_to_module.h" #endif #include "common/using_std_string.h" // This namespace contains helper functions. namespace { using google_breakpad::DumpOptions; using google_breakpad::DwarfCFIToModule; using google_breakpad::DwarfCUToModule; using google_breakpad::DwarfLineToModule; using google_breakpad::Module; #ifndef NO_STABS_SUPPORT using google_breakpad::StabsToModule; #endif using google_breakpad::scoped_ptr; // // FDWrapper // // Wrapper class to make sure opened file is closed. // class FDWrapper { public: explicit FDWrapper(int fd) : fd_(fd) {} ~FDWrapper() { if (fd_ != -1) close(fd_); } int get() { return fd_; } int release() { int fd = fd_; fd_ = -1; return fd; } private: int fd_; }; // // MmapWrapper // // Wrapper class to make sure mapped regions are unmapped. // class MmapWrapper { public: MmapWrapper() : is_set_(false) {} ~MmapWrapper() { if (is_set_ && base_ != NULL) { assert(size_ > 0); #ifndef _WIN32 munmap(base_, size_); #else UnmapViewOfFile(base_); CloseHandle(hMap_); #endif } } void *set(int obj_fd, size_t mapped_size) { #ifndef _WIN32 void *mapped_address = mmap(NULL, mapped_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, obj_fd, 0); if (mapped_address == MAP_FAILED) return NULL; #else HANDLE h = (HANDLE)_get_osfhandle(obj_fd); hMap_ = CreateFileMapping(h, NULL, PAGE_READONLY,0, 0, NULL); // XXX: should also use SEC_IMAGE_NO_EXECUTE on Windows 6.2 or later if (!hMap_) { return NULL; } void *mapped_address = MapViewOfFile(hMap_, FILE_MAP_READ, 0, 0, 0); if (!mapped_address) { CloseHandle(hMap_); return NULL; } #endif is_set_ = true; base_ = mapped_address; size_ = mapped_size; return mapped_address; } void release() { assert(is_set_); is_set_ = false; base_ = NULL; size_ = 0; } private: bool is_set_; void *base_; size_t size_; #ifdef _WIN32 HANDLE hMap_; #endif }; #ifndef NO_STABS_SUPPORT template bool LoadStabs(const typename ObjectFileReader::ObjectFileBase header, const typename ObjectFileReader::Section stab_section, const typename ObjectFileReader::Section stabstr_section, const bool big_endian, Module* module) { // A callback object to handle data from the STABS reader. StabsToModule handler(module); // Find the addresses of the STABS data, and create a STABS reader object. // On Linux, STABS entries always have 32-bit values, regardless of the // address size of the architecture whose code they're describing, and // the strings are always "unitized". const uint8_t* stabs = ObjectFileReader::GetSectionPointer(header, stab_section); const uint8_t* stabstr = ObjectFileReader::GetSectionPointer(header, stabstr_section); google_breakpad::StabsReader reader(stabs, ObjectFileReader::GetSectionSize(header, stab_section), stabstr, ObjectFileReader::GetSectionSize(header, stabstr_section), big_endian, 4, true, &handler); // Read the STABS data, and do post-processing. if (!reader.Process()) return false; handler.Finalize(); return true; } #endif // NO_STABS_SUPPORT // A line-to-module loader that accepts line number info parsed by // dwarf2reader::LineInfo and populates a Module and a line vector // with the results. class DumperLineToModule: public DwarfCUToModule::LineToModuleHandler { public: // Create a line-to-module converter using BYTE_READER. explicit DumperLineToModule(dwarf2reader::ByteReader *byte_reader) : byte_reader_(byte_reader) { } void StartCompilationUnit(const string& compilation_dir) { compilation_dir_ = compilation_dir; } void ReadProgram(const char *program, uint64 length, Module *module, std::vector *lines) { DwarfLineToModule handler(module, compilation_dir_, lines); dwarf2reader::LineInfo parser(program, length, byte_reader_, &handler); parser.Start(); } private: string compilation_dir_; dwarf2reader::ByteReader *byte_reader_; }; template bool LoadDwarf(const string& dwarf_filename, const typename ObjectFileReader::ObjectFileBase header, const bool big_endian, bool handle_inter_cu_refs, Module* module) { typedef typename ObjectFileReader::Section Shdr; const dwarf2reader::Endianness endianness = big_endian ? dwarf2reader::ENDIANNESS_BIG : dwarf2reader::ENDIANNESS_LITTLE; dwarf2reader::ByteReader byte_reader(endianness); // Construct a context for this file. DwarfCUToModule::FileContext file_context(dwarf_filename, module, handle_inter_cu_refs); // Build a map of the file's sections. int num_sections = ObjectFileReader::GetNumberOfSections(header); for (int i = 0; i < num_sections; ++i) { const Shdr section = ObjectFileReader::FindSectionByIndex(header, i); string name = ObjectFileReader::GetSectionName(header, section); const char* contents = reinterpret_cast(ObjectFileReader::GetSectionPointer(header, section)); file_context.AddSectionToSectionMap(name, contents, ObjectFileReader::GetSectionSize(header, section)); } // Parse all the compilation units in the .debug_info section. DumperLineToModule line_to_module(&byte_reader); dwarf2reader::SectionMap::const_iterator debug_info_entry = file_context.section_map().find(".debug_info"); assert(debug_info_entry != file_context.section_map().end()); const std::pair& debug_info_section = debug_info_entry->second; // This should never have been called if the file doesn't have a // .debug_info section. assert(debug_info_section.first); uint64 debug_info_length = debug_info_section.second; for (uint64 offset = 0; offset < debug_info_length;) { // Make a handler for the root DIE that populates MODULE with the // data that was found. DwarfCUToModule::WarningReporter reporter(dwarf_filename, offset); DwarfCUToModule root_handler(&file_context, &line_to_module, &reporter); // Make a Dwarf2Handler that drives the DIEHandler. dwarf2reader::DIEDispatcher die_dispatcher(&root_handler); // Make a DWARF parser for the compilation unit at OFFSET. dwarf2reader::CompilationUnit reader(file_context.section_map(), offset, &byte_reader, &die_dispatcher); // Process the entire compilation unit; get the offset of the next. offset += reader.Start(); } return true; } // Fill REGISTER_NAMES with the register names appropriate to the // machine architecture, indexed by the register // numbers used in DWARF call frame information. Return true on // success, or false if HEADER's machine architecture is not // supported. bool DwarfCFIRegisterNames(const char *architecture, std::vector* register_names) { if (strcmp(architecture, "x86" ) == 0) *register_names = DwarfCFIToModule::RegisterNames::I386(); else if (strcmp(architecture, "arm" ) == 0) *register_names = DwarfCFIToModule::RegisterNames::ARM(); else if (strcmp(architecture, "mips" ) == 0) *register_names = DwarfCFIToModule::RegisterNames::MIPS(); else if (strcmp(architecture, "x86_64" ) == 0) *register_names = DwarfCFIToModule::RegisterNames::X86_64(); else return false; return true; } template bool LoadDwarfCFI(const string& dwarf_filename, const typename ObjectFileReader::ObjectFileBase header, const char* section_name, const typename ObjectFileReader::Section section, const bool eh_frame, const typename ObjectFileReader::Section got_section, const typename ObjectFileReader::Section text_section, const bool big_endian, Module* module) { // Find the appropriate set of register names for this file's // architecture. const char *architecture = ObjectFileReader::Architecture(header); std::vector register_names; if (!DwarfCFIRegisterNames(architecture, ®ister_names)) { return false; } const dwarf2reader::Endianness endianness = big_endian ? dwarf2reader::ENDIANNESS_BIG : dwarf2reader::ENDIANNESS_LITTLE; // Find the call frame information and its size. const char* cfi = reinterpret_cast(ObjectFileReader::GetSectionPointer(header, section)); size_t cfi_size = ObjectFileReader::GetSectionSize(header, section); // Plug together the parser, handler, and their entourages. DwarfCFIToModule::Reporter module_reporter(dwarf_filename, section_name); DwarfCFIToModule handler(module, register_names, &module_reporter); dwarf2reader::ByteReader byte_reader(endianness); byte_reader.SetAddressSize(ObjectFileReader::kAddrSize); // Provide the base addresses for .eh_frame encoded pointers, if // possible. byte_reader.SetCFIDataBase(ObjectFileReader::GetSectionRVA(header, section) + ObjectFileReader::GetLoadingAddress(header), cfi); if (got_section) byte_reader.SetDataBase(ObjectFileReader::GetSectionRVA(header, got_section) + ObjectFileReader::GetLoadingAddress(header)); if (text_section) byte_reader.SetTextBase(ObjectFileReader::GetSectionRVA(header, text_section) + ObjectFileReader::GetLoadingAddress(header)); dwarf2reader::CallFrameInfo::Reporter dwarf_reporter(dwarf_filename, section_name); dwarf2reader::CallFrameInfo parser(cfi, cfi_size, &byte_reader, &handler, &dwarf_reporter, eh_frame); parser.Start(); return true; } bool LoadFile(const string& obj_file, MmapWrapper* map_wrapper, const void** header) { int obj_fd = open(obj_file.c_str(), O_RDONLY); if (obj_fd < 0) { fprintf(stderr, "Failed to open file '%s': %s\n", obj_file.c_str(), strerror(errno)); return false; } FDWrapper obj_fd_wrapper(obj_fd); struct stat st; if (fstat(obj_fd, &st) != 0 && st.st_size <= 0) { fprintf(stderr, "Unable to fstat file '%s': %s\n", obj_file.c_str(), strerror(errno)); return false; } *header = map_wrapper->set(obj_fd, st.st_size); if (!(*header)) { fprintf(stderr, "Failed to mmap file '%s': %s\n", obj_file.c_str(), strerror(errno)); return false; } return true; } // Read the .gnu_debuglink and get the debug file name. If anything goes // wrong, return an empty string. template string ReadDebugLink(const char* debuglink, size_t debuglink_size, const string& obj_file, const std::vector& debug_dirs) { size_t debuglink_len = strlen(debuglink) + 5; // '\0' + CRC32. debuglink_len = 4 * ((debuglink_len + 3) / 4); // Round to nearest 4 bytes. // Sanity check. if (debuglink_len != debuglink_size) { fprintf(stderr, "Mismatched .gnu_debuglink string / section size: " "%zx %zx\n", debuglink_len, debuglink_size); return ""; } bool found = false; int debuglink_fd = -1; string debuglink_path; std::vector::const_iterator it; for (it = debug_dirs.begin(); it < debug_dirs.end(); ++it) { const string& debug_dir = *it; debuglink_path = debug_dir + "/" + debuglink; debuglink_fd = open(debuglink_path.c_str(), O_RDONLY); if (debuglink_fd >= 0) { found = true; break; } } if (!found) { fprintf(stderr, "Failed to find debug file for '%s' after trying:\n", obj_file.c_str()); for (it = debug_dirs.begin(); it < debug_dirs.end(); ++it) { const string debug_dir = *it; fprintf(stderr, " %s/%s\n", debug_dir.c_str(), debuglink); } return ""; } FDWrapper debuglink_fd_wrapper(debuglink_fd); // TODO(thestig) check the CRC-32 at the end of the .gnu_debuglink // section. return debuglink_path; } // // LoadSymbolsInfo // // Holds the state between the two calls to LoadSymbols() in case it's necessary // to follow the .gnu_debuglink section and load debug information from a // different file. // template class LoadSymbolsInfo { public: typedef typename ObjectFileReader::Addr Addr; explicit LoadSymbolsInfo(const std::vector& dbg_dirs) : debug_dirs_(dbg_dirs), has_loading_addr_(false) {} // Keeps track of which sections have been loaded so sections don't // accidentally get loaded twice from two different files. void LoadedSection(const string §ion) { if (loaded_sections_.count(section) == 0) { loaded_sections_.insert(section); } else { fprintf(stderr, "Section %s has already been loaded.\n", section.c_str()); } } // The file and linked debug file are expected to have the same preferred // loading address. void set_loading_addr(Addr addr, const string &filename) { if (!has_loading_addr_) { loading_addr_ = addr; loaded_file_ = filename; return; } if (addr != loading_addr_) { fprintf(stderr, "file '%s' and debug file '%s' " "have different load addresses.\n", loaded_file_.c_str(), filename.c_str()); assert(false); } } // Setters and getters const std::vector& debug_dirs() const { return debug_dirs_; } string debuglink_file() const { return debuglink_file_; } void set_debuglink_file(string file) { debuglink_file_ = file; } private: const std::vector& debug_dirs_; // Directories in which to // search for the debug file. string debuglink_file_; // Full path to the debug file. bool has_loading_addr_; // Indicate if LOADING_ADDR_ is valid. Addr loading_addr_; // Saves the preferred loading address from the // first call to LoadSymbols(). string loaded_file_; // Name of the file loaded from the first call to // LoadSymbols(). std::set loaded_sections_; // Tracks the Loaded sections // between calls to LoadSymbols(). }; template bool LoadSymbols(const string& obj_file, const bool big_endian, const typename ObjectFileReader::ObjectFileBase header, const bool read_gnu_debug_link, LoadSymbolsInfo* info, const DumpOptions& options, Module* module) { typedef typename ObjectFileReader::Addr Addr; typedef typename ObjectFileReader::Section Shdr; Addr loading_addr = ObjectFileReader::GetLoadingAddress(header); module->SetLoadAddress(loading_addr); info->set_loading_addr(loading_addr, obj_file); bool found_debug_info_section = false; bool found_usable_info = false; if (options.symbol_data != ONLY_CFI) { #ifndef NO_STABS_SUPPORT // Look for STABS debugging information, and load it if present. const Shdr stab_section = ObjectFileReader::FindSectionByName(".stab", header); if (stab_section) { const Shdr stabstr_section = ObjectFileReader::FindLinkedSection(header, stab_section); if (stabstr_section) { found_debug_info_section = true; found_usable_info = true; info->LoadedSection(".stab"); if (!LoadStabs(header, stab_section, stabstr_section, big_endian, module)) { fprintf(stderr, "%s: \".stab\" section found, but failed to load" " STABS debugging information\n", obj_file.c_str()); } } } #endif // NO_STABS_SUPPORT // Look for DWARF debugging information, and load it if present. const Shdr dwarf_section = ObjectFileReader::FindSectionByName(".debug_info", header); if (dwarf_section) { found_debug_info_section = true; found_usable_info = true; info->LoadedSection(".debug_info"); if (!LoadDwarf(obj_file, header, big_endian, options.handle_inter_cu_refs, module)) { fprintf(stderr, "%s: \".debug_info\" section found, but failed to load " "DWARF debugging information\n", obj_file.c_str()); } } } if (options.symbol_data != NO_CFI) { // Dwarf Call Frame Information (CFI) is actually independent from // the other DWARF debugging information, and can be used alone. const Shdr dwarf_cfi_section = ObjectFileReader::FindSectionByName(".debug_frame", header); if (dwarf_cfi_section) { // Ignore the return value of this function; even without call frame // information, the other debugging information could be perfectly // useful. info->LoadedSection(".debug_frame"); bool result = LoadDwarfCFI(obj_file, header, ".debug_frame", dwarf_cfi_section, false, 0, 0, big_endian, module); found_usable_info = found_usable_info || result; } // Linux C++ exception handling information can also provide // unwinding data. const Shdr eh_frame_section = ObjectFileReader::FindSectionByName(".eh_frame", header); if (eh_frame_section) { // Pointers in .eh_frame data may be relative to the base addresses of // certain sections. Provide those sections if present. const Shdr got_section = ObjectFileReader::FindSectionByName(".got", header); const Shdr text_section = ObjectFileReader::FindSectionByName(".text", header); info->LoadedSection(".eh_frame"); // As above, ignore the return value of this function. bool result = LoadDwarfCFI(obj_file, header, ".eh_frame", eh_frame_section, true, got_section, text_section, big_endian, module); found_usable_info = found_usable_info || result; } } if (!found_debug_info_section) { fprintf(stderr, "%s: file contains no debugging information" " (no \".stab\" or \".debug_info\" sections)\n", obj_file.c_str()); // Failed, but maybe there's a .gnu_debuglink section? if (read_gnu_debug_link) { const Shdr gnu_debuglink_section = ObjectFileReader::FindSectionByName(".gnu_debuglink", header); if (gnu_debuglink_section) { if (!info->debug_dirs().empty()) { const char* debuglink_contents = reinterpret_cast (ObjectFileReader::GetSectionPointer(header, gnu_debuglink_section)); string debuglink_file = ReadDebugLink(debuglink_contents, ObjectFileReader::GetSectionSize(header, gnu_debuglink_section), obj_file, info->debug_dirs()); info->set_debuglink_file(debuglink_file); } else { fprintf(stderr, ".gnu_debuglink section found in '%s', " "but no debug path specified.\n", obj_file.c_str()); } } else { fprintf(stderr, "%s does not contain a .gnu_debuglink section.\n", obj_file.c_str()); } } else { if (options.symbol_data != ONLY_CFI) { // The caller doesn't want to consult .gnu_debuglink. // See if there are export symbols available. bool result = ObjectFileReader::ExportedSymbolsToModule(header, module); found_usable_info = found_usable_info || result; } // Return true if some usable information was found, since // the caller doesn't want to use .gnu_debuglink. return found_usable_info; } // No debug info was found, let the user try again with .gnu_debuglink // if present. return false; } return true; } // Return the non-directory portion of FILENAME: the portion after the // last slash, or the whole filename if there are no slashes. string BaseFileName(const string &filename) { // Lots of copies! basename's behavior is less than ideal. char *c_filename = strdup(filename.c_str()); string base = basename(c_filename); free(c_filename); return base; } template bool ReadSymbolDataFromObjectFile( const typename ObjectFileReader::ObjectFileBase header, const string& obj_filename, const std::vector& debug_dirs, const DumpOptions& options, Module** out_module) { typedef typename ObjectFileReader::Section Shdr; *out_module = NULL; string identifier = ObjectFileReader::FileIdentifierFromMappedFile(header); if (identifier.empty()) { fprintf(stderr, "%s: unable to generate file identifier\n", obj_filename.c_str()); return false; } const char *architecture = ObjectFileReader::Architecture(header); if (!architecture) { return false; } // Figure out what endianness this file is. bool big_endian; if (!ObjectFileReader::Endianness(header, &big_endian)) return false; string name = BaseFileName(obj_filename); string os = "windows"; string id = identifier; LoadSymbolsInfo info(debug_dirs); scoped_ptr module(new Module(name, os, architecture, id)); if (!LoadSymbols(obj_filename, big_endian, header, !debug_dirs.empty(), &info, options, module.get())) { const string debuglink_file = info.debuglink_file(); if (debuglink_file.empty()) return false; // Load debuglink file. fprintf(stderr, "Found debugging info in %s\n", debuglink_file.c_str()); MmapWrapper debug_map_wrapper; typename ObjectFileReader::ObjectFileBase debug_header = NULL; if (!LoadFile(debuglink_file, &debug_map_wrapper, reinterpret_cast(&debug_header))) return false; if (!ObjectFileReader::IsValid(debug_header)) { fprintf(stderr, "Not a valid file: %s\n", debuglink_file.c_str()); return false; } // Sanity checks to make sure everything matches up. const char *debug_architecture = ObjectFileReader::Architecture(debug_header); if (!debug_architecture) { return false; } if (strcmp(architecture, debug_architecture)) { fprintf(stderr, "%s with machine architecture %s does not match " "%s with architecture %s\n", debuglink_file.c_str(), debug_architecture, obj_filename.c_str(), architecture); return false; } bool debug_big_endian; if (!ObjectFileReader::Endianness(debug_header, &debug_big_endian)) return false; if (debug_big_endian != big_endian) { fprintf(stderr, "%s and %s does not match in endianness\n", obj_filename.c_str(), debuglink_file.c_str()); return false; } if (!LoadSymbols(debuglink_file, debug_big_endian, debug_header, false, &info, options, module.get())) { return false; } } *out_module = module.release(); return true; } } // namespace #endif // COMMON_PECOFF_DUMP_SYMBOLS_INL_H