From 07e521c396be01162b4cb8119954401b7eaa510c Mon Sep 17 00:00:00 2001 From: "benchan@chromium.org" Date: Sat, 7 Jan 2012 02:25:22 +0000 Subject: Add utilities for processing Linux core dump files. This patch is part of a bigger patch that helps merging the breakpad code with the modified version in Chromium OS. Specifically, this patch makes the following changes: 1. Add an ElfCoreDump class for processing Linux core dump files, which will later be used to implement the core dump to minidump conversion. 2. Add a CrashGenerator class for generating a crash with a core dump file for testing the functionalities of ElfCoreDump. 3. Move some utility functions for reading/writing files to file_utils.h. BUG=455 TEST=Tested the following: 1. Build on 32-bit and 64-bit Linux with gcc 4.4.3 and gcc 4.6. 2. Build on Mac OS X 10.6.8 with gcc 4.2 and clang 3.0 (with latest gmock). 3. All unit tests pass. Review URL: http://breakpad.appspot.com/337001 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@900 4c0a9323-5329-0410-9bdc-e9ce6186880e --- src/common/linux/elf_core_dump.cc | 179 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 179 insertions(+) create mode 100644 src/common/linux/elf_core_dump.cc (limited to 'src/common/linux/elf_core_dump.cc') diff --git a/src/common/linux/elf_core_dump.cc b/src/common/linux/elf_core_dump.cc new file mode 100644 index 00000000..0e7db7b1 --- /dev/null +++ b/src/common/linux/elf_core_dump.cc @@ -0,0 +1,179 @@ +// 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. + +// elf_core_dump.cc: Implement google_breakpad::ElfCoreDump. +// See elf_core_dump.h for details. + +#include "common/linux/elf_core_dump.h" + +#include +#include + +namespace google_breakpad { + +// Implementation of ElfCoreDump::Note. + +ElfCoreDump::Note::Note() {} + +ElfCoreDump::Note::Note(const MemoryRange& content) : content_(content) {} + +bool ElfCoreDump::Note::IsValid() const { + return GetHeader() != NULL; +} + +const ElfCoreDump::Nhdr* ElfCoreDump::Note::GetHeader() const { + return content_.GetData(0); +} + +ElfCoreDump::Word ElfCoreDump::Note::GetType() const { + const Nhdr* header = GetHeader(); + // 0 is not being used as a NOTE type. + return header ? header->n_type : 0; +} + +MemoryRange ElfCoreDump::Note::GetName() const { + const Nhdr* header = GetHeader(); + if (header) { + return content_.Subrange(sizeof(Nhdr), header->n_namesz); + } + return MemoryRange(); +} + +MemoryRange ElfCoreDump::Note::GetDescription() const { + const Nhdr* header = GetHeader(); + if (header) { + return content_.Subrange(AlignedSize(sizeof(Nhdr) + header->n_namesz), + header->n_descsz); + } + return MemoryRange(); +} + +ElfCoreDump::Note ElfCoreDump::Note::GetNextNote() const { + MemoryRange next_content; + const Nhdr* header = GetHeader(); + if (header) { + size_t next_offset = AlignedSize(sizeof(Nhdr) + header->n_namesz); + next_offset = AlignedSize(next_offset + header->n_descsz); + next_content = + content_.Subrange(next_offset, content_.length() - next_offset); + } + return Note(next_content); +} + +// static +size_t ElfCoreDump::Note::AlignedSize(size_t size) { + size_t mask = sizeof(Word) - 1; + return (size + mask) & ~mask; +} + + +// Implementation of ElfCoreDump. + +ElfCoreDump::ElfCoreDump() {} + +ElfCoreDump::ElfCoreDump(const MemoryRange& content) + : content_(content) { +} + +void ElfCoreDump::SetContent(const MemoryRange& content) { + content_ = content; +} + +bool ElfCoreDump::IsValid() const { + const Ehdr* header = GetHeader(); + return (header && + header->e_ident[0] == ELFMAG0 && + header->e_ident[1] == ELFMAG1 && + header->e_ident[2] == ELFMAG2 && + header->e_ident[3] == ELFMAG3 && + header->e_ident[4] == kClass && + header->e_version == EV_CURRENT && + header->e_type == ET_CORE); +} + +const ElfCoreDump::Ehdr* ElfCoreDump::GetHeader() const { + return content_.GetData(0); +} + +const ElfCoreDump::Phdr* ElfCoreDump::GetProgramHeader(unsigned index) const { + const Ehdr* header = GetHeader(); + if (header) { + return reinterpret_cast(content_.GetArrayElement( + header->e_phoff, header->e_phentsize, index)); + } + return NULL; +} + +const ElfCoreDump::Phdr* ElfCoreDump::GetFirstProgramHeaderOfType( + Word type) const { + for (unsigned i = 0, n = GetProgramHeaderCount(); i < n; ++i) { + const Phdr* program = GetProgramHeader(i); + if (program->p_type == type) { + return program; + } + } + return NULL; +} + +unsigned ElfCoreDump::GetProgramHeaderCount() const { + const Ehdr* header = GetHeader(); + return header ? header->e_phnum : 0; +} + +bool ElfCoreDump::CopyData(void* buffer, Addr virtual_address, size_t length) { + for (unsigned i = 0, n = GetProgramHeaderCount(); i < n; ++i) { + const Phdr* program = GetProgramHeader(i); + if (program->p_type != PT_LOAD) + continue; + + size_t offset_in_segment = virtual_address - program->p_vaddr; + if (virtual_address >= program->p_vaddr && + offset_in_segment < program->p_filesz) { + const void* data = + content_.GetData(program->p_offset + offset_in_segment, length); + if (data) { + memcpy(buffer, data, length); + return true; + } + } + } + return false; +} + +ElfCoreDump::Note ElfCoreDump::GetFirstNote() const { + MemoryRange note_content; + const Phdr* program_header = GetFirstProgramHeaderOfType(PT_NOTE); + if (program_header) { + note_content = content_.Subrange(program_header->p_offset, + program_header->p_filesz); + } + return Note(note_content); +} + +} // namespace google_breakpad -- cgit v1.2.1