Added an option (-i) to have dump_syms output header information only.

It is often helpful to check if a particular symbol file dumped by
dump_syms actually matches a version of a binary file we have. The
symbol output contains an ID which can be used to see if it matches
the binary file. Unfortunately, this ID is internally calculated
and not a standard hash of the binary file. Being able to output the
header information only will allow users to determine whether their
symbol file is up to date or not.

R=jochen@chromium.org
BUG=561447

Review URL: https://codereview.chromium.org/1864823002 .

Patch from David Yen <dyen@chromium.org>.
This commit is contained in:
David Yen 2016-04-08 04:37:45 +02:00 committed by Jochen Eisinger
parent 32901f6d4c
commit b0e5f26233
6 changed files with 188 additions and 83 deletions

View file

@ -901,19 +901,12 @@ bool SanitizeDebugFile(const typename ElfClass::Ehdr* debug_elf_header,
}
template<typename ElfClass>
bool ReadSymbolDataElfClass(const typename ElfClass::Ehdr* elf_header,
const string& obj_filename,
const std::vector<string>& debug_dirs,
const DumpOptions& options,
Module** out_module) {
typedef typename ElfClass::Ehdr Ehdr;
*out_module = NULL;
bool InitModuleForElfClass(const typename ElfClass::Ehdr* elf_header,
const string& obj_filename,
scoped_ptr<Module>& module) {
PageAllocator allocator;
wasteful_vector<uint8_t> identifier(&allocator, kDefaultBuildIdSize);
if (!FileID::ElfFileIdentifierFromMappedFile(elf_header,
identifier)) {
if (!FileID::ElfFileIdentifierFromMappedFile(elf_header, identifier)) {
fprintf(stderr, "%s: unable to generate file identifier\n",
obj_filename.c_str());
return false;
@ -926,11 +919,6 @@ bool ReadSymbolDataElfClass(const typename ElfClass::Ehdr* elf_header,
return false;
}
// Figure out what endianness this file is.
bool big_endian;
if (!ElfEndianness<ElfClass>(elf_header, &big_endian))
return false;
string name = BaseFileName(obj_filename);
string os = "Linux";
// Add an extra "0" at the end. PDB files on Windows have an 'age'
@ -938,8 +926,32 @@ bool ReadSymbolDataElfClass(const typename ElfClass::Ehdr* elf_header,
// really used or necessary on other platforms, but be consistent.
string id = FileID::ConvertIdentifierToUUIDString(identifier) + "0";
module.reset(new Module(name, os, architecture, id));
return true;
}
template<typename ElfClass>
bool ReadSymbolDataElfClass(const typename ElfClass::Ehdr* elf_header,
const string& obj_filename,
const std::vector<string>& debug_dirs,
const DumpOptions& options,
Module** out_module) {
typedef typename ElfClass::Ehdr Ehdr;
*out_module = NULL;
scoped_ptr<Module> module;
if (!InitModuleForElfClass<ElfClass>(elf_header, obj_filename, module)) {
return false;
}
// Figure out what endianness this file is.
bool big_endian;
if (!ElfEndianness<ElfClass>(elf_header, &big_endian))
return false;
LoadSymbolsInfo<ElfClass> info(debug_dirs);
scoped_ptr<Module> module(new Module(name, os, architecture, id));
if (!LoadSymbols<ElfClass>(obj_filename, big_endian, elf_header,
!debug_dirs.empty(), &info,
options, module.get())) {
@ -954,7 +966,9 @@ bool ReadSymbolDataElfClass(const typename ElfClass::Ehdr* elf_header,
if (!LoadELF(debuglink_file, &debug_map_wrapper,
reinterpret_cast<void**>(&debug_elf_header)) ||
!SanitizeDebugFile<ElfClass>(debug_elf_header, debuglink_file,
obj_filename, architecture, big_endian)) {
obj_filename,
module->architecture().c_str(),
big_endian)) {
return false;
}
@ -1012,6 +1026,45 @@ bool WriteSymbolFile(const string &obj_file,
return result;
}
// Read the selected object file's debugging information, and write out the
// header only to |stream|. Return true on success; if an error occurs, report
// it and return false.
bool WriteSymbolFileHeader(const string& obj_file,
std::ostream &sym_stream) {
MmapWrapper map_wrapper;
void* elf_header = NULL;
if (!LoadELF(obj_file, &map_wrapper, &elf_header)) {
fprintf(stderr, "Could not load ELF file: %s\n", obj_file.c_str());
return false;
}
if (!IsValidElf(elf_header)) {
fprintf(stderr, "Not a valid ELF file: %s\n", obj_file.c_str());
return false;
}
int elfclass = ElfClass(elf_header);
scoped_ptr<Module> module;
if (elfclass == ELFCLASS32) {
if (!InitModuleForElfClass<ElfClass32>(
reinterpret_cast<const Elf32_Ehdr*>(elf_header), obj_file, module)) {
fprintf(stderr, "Failed to load ELF module: %s\n", obj_file.c_str());
return false;
}
} else if (elfclass == ELFCLASS64) {
if (!InitModuleForElfClass<ElfClass64>(
reinterpret_cast<const Elf64_Ehdr*>(elf_header), obj_file, module)) {
fprintf(stderr, "Failed to load ELF module: %s\n", obj_file.c_str());
return false;
}
} else {
fprintf(stderr, "Unsupported module file: %s\n", obj_file.c_str());
return false;
}
return module->Write(sym_stream, ALL_SYMBOL_DATA);
}
bool ReadSymbolData(const string& obj_file,
const std::vector<string>& debug_dirs,
const DumpOptions& options,

View file

@ -67,6 +67,12 @@ bool WriteSymbolFile(const string &obj_file,
const DumpOptions& options,
std::ostream &sym_stream);
// Read the selected object file's debugging information, and write out the
// header only to |stream|. Return true on success; if an error occurs, report
// it and return false.
bool WriteSymbolFileHeader(const string& obj_file,
std::ostream &sym_stream);
// As above, but simply return the debugging information in MODULE
// instead of writing it to a stream. The caller owns the resulting
// Module object and must delete it when finished.

View file

@ -328,6 +328,65 @@ class DumpSymbols::DumperLineToModule:
dwarf2reader::ByteReader *byte_reader_; // WEAK
};
bool DumpSymbols::CreateEmptyModule(scoped_ptr<Module>& module) {
// Select an object file, if SetArchitecture hasn't been called to set one
// explicitly.
if (!selected_object_file_) {
// If there's only one architecture, that's the one.
if (object_files_.size() == 1)
selected_object_file_ = &object_files_[0];
else {
// Look for an object file whose architecture matches our own.
const NXArchInfo *local_arch = NXGetLocalArchInfo();
if (!SetArchitecture(local_arch->cputype, local_arch->cpusubtype)) {
fprintf(stderr, "%s: object file contains more than one"
" architecture, none of which match the current"
" architecture; specify an architecture explicitly"
" with '-a ARCH' to resolve the ambiguity\n",
object_filename_.c_str());
return false;
}
}
}
assert(selected_object_file_);
// Find the name of the selected file's architecture, to appear in
// the MODULE record and in error messages.
const NXArchInfo *selected_arch_info =
google_breakpad::BreakpadGetArchInfoFromCpuType(
selected_object_file_->cputype, selected_object_file_->cpusubtype);
const char *selected_arch_name = selected_arch_info->name;
if (strcmp(selected_arch_name, "i386") == 0)
selected_arch_name = "x86";
// Produce a name to use in error messages that includes the
// filename, and the architecture, if there is more than one.
selected_object_name_ = object_filename_;
if (object_files_.size() > 1) {
selected_object_name_ += ", architecture ";
selected_object_name_ + selected_arch_name;
}
// Compute a module name, to appear in the MODULE record.
string module_name = object_filename_;
module_name = basename(&module_name[0]);
// Choose an identifier string, to appear in the MODULE record.
string identifier = Identifier();
if (identifier.empty())
return false;
identifier += "0";
// Create a module to hold the debugging information.
module.reset(new Module(module_name,
"mac",
selected_arch_name,
identifier));
return true;
}
bool DumpSymbols::ReadDwarf(google_breakpad::Module *module,
const mach_o::Reader &macho_reader,
const mach_o::SectionMap &dwarf_sections,
@ -535,61 +594,9 @@ bool DumpSymbols::LoadCommandDumper::SymtabCommand(const ByteBuffer &entries,
}
bool DumpSymbols::ReadSymbolData(Module** out_module) {
// Select an object file, if SetArchitecture hasn't been called to set one
// explicitly.
if (!selected_object_file_) {
// If there's only one architecture, that's the one.
if (object_files_.size() == 1)
selected_object_file_ = &object_files_[0];
else {
// Look for an object file whose architecture matches our own.
const NXArchInfo *local_arch = NXGetLocalArchInfo();
if (!SetArchitecture(local_arch->cputype, local_arch->cpusubtype)) {
fprintf(stderr, "%s: object file contains more than one"
" architecture, none of which match the current"
" architecture; specify an architecture explicitly"
" with '-a ARCH' to resolve the ambiguity\n",
object_filename_.c_str());
return false;
}
}
}
assert(selected_object_file_);
// Find the name of the selected file's architecture, to appear in
// the MODULE record and in error messages.
const NXArchInfo *selected_arch_info =
google_breakpad::BreakpadGetArchInfoFromCpuType(
selected_object_file_->cputype, selected_object_file_->cpusubtype);
const char *selected_arch_name = selected_arch_info->name;
if (strcmp(selected_arch_name, "i386") == 0)
selected_arch_name = "x86";
// Produce a name to use in error messages that includes the
// filename, and the architecture, if there is more than one.
selected_object_name_ = object_filename_;
if (object_files_.size() > 1) {
selected_object_name_ += ", architecture ";
selected_object_name_ + selected_arch_name;
}
// Compute a module name, to appear in the MODULE record.
string module_name = object_filename_;
module_name = basename(&module_name[0]);
// Choose an identifier string, to appear in the MODULE record.
string identifier = Identifier();
if (identifier.empty())
scoped_ptr<Module> module;
if (!CreateEmptyModule(module))
return false;
identifier += "0";
// Create a module to hold the debugging information.
scoped_ptr<Module> module(new Module(module_name,
"mac",
selected_arch_name,
identifier));
// Parse the selected object file.
mach_o::Reader::Reporter reporter(selected_object_name_);
@ -624,4 +631,15 @@ bool DumpSymbols::WriteSymbolFile(std::ostream &stream) {
return false;
}
// Read the selected object file's debugging information, and write out the
// header only to |stream|. Return true on success; if an error occurs, report
// it and return false.
bool DumpSymbols::WriteSymbolFileHeader(std::ostream &stream) {
scoped_ptr<Module> module;
if (!CreateEmptyModule(module))
return false;
return module->Write(stream, symbol_data_);
}
} // namespace google_breakpad

View file

@ -112,6 +112,11 @@ class DumpSymbols {
// return false.
bool WriteSymbolFile(std::ostream &stream);
// Read the selected object file's debugging information, and write out the
// header only to |stream|. Return true on success; if an error occurs, report
// it and return false.
bool WriteSymbolFileHeader(std::ostream &stream);
// As above, but simply return the debugging information in module
// instead of writing it to a stream. The caller owns the resulting
// module object and must delete it when finished.
@ -130,6 +135,10 @@ class DumpSymbols {
// Return an identifier string for the file this DumpSymbols is dumping.
std::string Identifier();
// Creates an empty module object.
bool CreateEmptyModule(scoped_ptr<Module>& module);
// Read debugging information from |dwarf_sections|, which was taken from
// |macho_reader|, and add it to |module|. On success, return true;
// on failure, report the problem and return false.

View file

@ -39,11 +39,13 @@
#include "common/linux/dump_symbols.h"
using google_breakpad::WriteSymbolFile;
using google_breakpad::WriteSymbolFileHeader;
int usage(const char* self) {
fprintf(stderr, "Usage: %s [OPTION] <binary-with-debugging-info> "
"[directories-for-debug-file]\n\n", self);
fprintf(stderr, "Options:\n");
fprintf(stderr, " -i: Output module header information only.\n");
fprintf(stderr, " -c Do not generate CFI section\n");
fprintf(stderr, " -r Do not handle inter-compilation unit references\n");
fprintf(stderr, " -v Print all warnings to stderr\n");
@ -53,27 +55,29 @@ int usage(const char* self) {
int main(int argc, char **argv) {
if (argc < 2)
return usage(argv[0]);
bool header_only = false;
bool cfi = true;
bool handle_inter_cu_refs = true;
bool log_to_stderr = false;
int arg_index = 1;
while (arg_index < argc && strlen(argv[arg_index]) > 0 &&
argv[arg_index][0] == '-') {
if (strcmp("-c", argv[arg_index]) == 0) {
if (strcmp("-i", argv[arg_index]) == 0) {
header_only = true;
} else if (strcmp("-c", argv[arg_index]) == 0) {
cfi = false;
} else if (strcmp("-r", argv[arg_index]) == 0) {
handle_inter_cu_refs = false;
} else if (strcmp("-v", argv[arg_index]) == 0) {
log_to_stderr = true;
} else {
printf("2.4 %s\n", argv[arg_index]);
return usage(argv[0]);
}
++arg_index;
}
if (arg_index == argc)
return usage(argv[0]);
// Save stderr so it can be used below.
FILE* saved_stderr = fdopen(dup(fileno(stderr)), "w");
if (!log_to_stderr) {
@ -82,7 +86,6 @@ int main(int argc, char **argv) {
// Add this brace section to silence gcc warnings.
}
}
const char* binary;
std::vector<string> debug_dirs;
binary = argv[arg_index];
@ -92,11 +95,18 @@ int main(int argc, char **argv) {
debug_dirs.push_back(argv[debug_dir_index]);
}
SymbolData symbol_data = cfi ? ALL_SYMBOL_DATA : NO_CFI;
google_breakpad::DumpOptions options(symbol_data, handle_inter_cu_refs);
if (!WriteSymbolFile(binary, debug_dirs, options, std::cout)) {
fprintf(saved_stderr, "Failed to write symbol file.\n");
return 1;
if (header_only) {
if (!WriteSymbolFileHeader(binary, std::cout)) {
fprintf(saved_stderr, "Failed to process file.\n");
return 1;
}
} else {
SymbolData symbol_data = cfi ? ALL_SYMBOL_DATA : NO_CFI;
google_breakpad::DumpOptions options(symbol_data, handle_inter_cu_refs);
if (!WriteSymbolFile(binary, debug_dirs, options, std::cout)) {
fprintf(saved_stderr, "Failed to write symbol file.\n");
return 1;
}
}
return 0;

View file

@ -51,11 +51,13 @@ using std::vector;
struct Options {
Options()
: srcPath(), dsymPath(), arch(), cfi(true), handle_inter_cu_refs(true) {}
: srcPath(), dsymPath(), arch(), header_only(false),
cfi(true), handle_inter_cu_refs(true) {}
string srcPath;
string dsymPath;
const NXArchInfo *arch;
bool header_only;
bool cfi;
bool handle_inter_cu_refs;
};
@ -151,6 +153,9 @@ static bool Start(const Options &options) {
}
}
if (options.header_only)
return dump_symbols.WriteSymbolFileHeader(std::cout);
// Read the primary file into a Breakpad Module.
Module* module = NULL;
if (!dump_symbols.ReadSymbolData(&module))
@ -189,6 +194,7 @@ static void Usage(int argc, const char *argv[]) {
fprintf(stderr, "Output a Breakpad symbol file from a Mach-o file.\n");
fprintf(stderr, "Usage: %s [-a ARCHITECTURE] [-c] [-g dSYM path] "
"<Mach-o file>\n", argv[0]);
fprintf(stderr, "\t-i: Output module header information only.\n");
fprintf(stderr, "\t-a: Architecture type [default: native, or whatever is\n");
fprintf(stderr, "\t in the file, if it contains only one architecture]\n");
fprintf(stderr, "\t-g: Debug symbol file (dSYM) to dump in addition to the "
@ -204,8 +210,11 @@ static void SetupOptions(int argc, const char *argv[], Options *options) {
extern int optind;
signed char ch;
while ((ch = getopt(argc, (char * const *)argv, "a:g:chr?")) != -1) {
while ((ch = getopt(argc, (char * const *)argv, "ia:g:chr?")) != -1) {
switch (ch) {
case 'i':
options->header_only = true;
break;
case 'a': {
const NXArchInfo *arch_info =
google_breakpad::BreakpadGetArchInfoFromName(optarg);