/thirdparty/breakpad/common/mac/macho_walker.cc
http://github.com/tomahawk-player/tomahawk · C++ · 267 lines · 182 code · 42 blank · 43 comment · 55 complexity · f725888230b609aeb70cb6fa5fd31836 MD5 · raw file
- // Copyright (c) 2006, 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.
- // macho_walker.cc: Iterate over the load commands in a mach-o file
- //
- // See macho_walker.h for documentation
- //
- // Author: Dan Waylonis
- extern "C" { // necessary for Leopard
- #include <assert.h>
- #include <fcntl.h>
- #include <mach-o/arch.h>
- #include <mach-o/loader.h>
- #include <mach-o/swap.h>
- #include <string.h>
- #include <unistd.h>
- }
- #include "common/mac/byteswap.h"
- #include "common/mac/macho_walker.h"
- #include "common/mac/macho_utilities.h"
- namespace MacFileUtilities {
- MachoWalker::MachoWalker(const char *path, LoadCommandCallback callback,
- void *context)
- : file_(0),
- memory_(NULL),
- memory_size_(0),
- callback_(callback),
- callback_context_(context),
- current_header_(NULL),
- current_header_size_(0),
- current_header_offset_(0) {
- file_ = open(path, O_RDONLY);
- }
- MachoWalker::MachoWalker(void *memory, size_t size,
- LoadCommandCallback callback, void *context)
- : file_(0),
- memory_(memory),
- memory_size_(size),
- callback_(callback),
- callback_context_(context),
- current_header_(NULL),
- current_header_size_(0),
- current_header_offset_(0) {
- }
- MachoWalker::~MachoWalker() {
- if (file_ != -1)
- close(file_);
- }
- int MachoWalker::ValidateCPUType(int cpu_type) {
- // If the user didn't specify, use the local architecture.
- if (cpu_type == 0) {
- const NXArchInfo *arch = NXGetLocalArchInfo();
- assert(arch);
- cpu_type = arch->cputype;
- }
- return cpu_type;
- }
- bool MachoWalker::WalkHeader(int cpu_type) {
- int valid_cpu_type = ValidateCPUType(cpu_type);
- off_t offset;
- if (FindHeader(valid_cpu_type, offset)) {
- if (cpu_type & CPU_ARCH_ABI64)
- return WalkHeader64AtOffset(offset);
- return WalkHeaderAtOffset(offset);
- }
- return false;
- }
- bool MachoWalker::ReadBytes(void *buffer, size_t size, off_t offset) {
- if (memory_) {
- if (offset < 0)
- return false;
- bool result = true;
- if (offset + size > memory_size_) {
- if (static_cast<size_t>(offset) >= memory_size_)
- return false;
- size = memory_size_ - offset;
- result = false;
- }
- memcpy(buffer, static_cast<char *>(memory_) + offset, size);
- return result;
- } else {
- return pread(file_, buffer, size, offset) == (ssize_t)size;
- }
- }
- bool MachoWalker::CurrentHeader(struct mach_header_64 *header, off_t *offset) {
- if (current_header_) {
- memcpy(header, current_header_, sizeof(mach_header_64));
- *offset = current_header_offset_;
- return true;
- }
- return false;
- }
- bool MachoWalker::FindHeader(int cpu_type, off_t &offset) {
- int valid_cpu_type = ValidateCPUType(cpu_type);
- // Read the magic bytes that's common amongst all mach-o files
- uint32_t magic;
- if (!ReadBytes(&magic, sizeof(magic), 0))
- return false;
- offset = sizeof(magic);
- // Figure out what type of file we've got
- bool is_fat = false;
- if (magic == FAT_MAGIC || magic == FAT_CIGAM) {
- is_fat = true;
- }
- else if (magic != MH_MAGIC && magic != MH_CIGAM && magic != MH_MAGIC_64 &&
- magic != MH_CIGAM_64) {
- return false;
- }
- if (!is_fat) {
- // If we don't have a fat header, check if the cpu type matches the single
- // header
- cpu_type_t header_cpu_type;
- if (!ReadBytes(&header_cpu_type, sizeof(header_cpu_type), offset))
- return false;
- if (magic == MH_CIGAM || magic == MH_CIGAM_64)
- header_cpu_type = ByteSwap(header_cpu_type);
- if (valid_cpu_type != header_cpu_type)
- return false;
- offset = 0;
- return true;
- } else {
- // Read the fat header and find an appropriate architecture
- offset = 0;
- struct fat_header fat;
- if (!ReadBytes(&fat, sizeof(fat), offset))
- return false;
- if (NXHostByteOrder() != NX_BigEndian)
- swap_fat_header(&fat, NXHostByteOrder());
- offset += sizeof(fat);
- // Search each architecture for the desired one
- struct fat_arch arch;
- for (uint32_t i = 0; i < fat.nfat_arch; ++i) {
- if (!ReadBytes(&arch, sizeof(arch), offset))
- return false;
- if (NXHostByteOrder() != NX_BigEndian)
- swap_fat_arch(&arch, 1, NXHostByteOrder());
- if (arch.cputype == valid_cpu_type) {
- offset = arch.offset;
- return true;
- }
- offset += sizeof(arch);
- }
- }
- return false;
- }
- bool MachoWalker::WalkHeaderAtOffset(off_t offset) {
- struct mach_header header;
- if (!ReadBytes(&header, sizeof(header), offset))
- return false;
- bool swap = (header.magic == MH_CIGAM);
- if (swap)
- swap_mach_header(&header, NXHostByteOrder());
- // Copy the data into the mach_header_64 structure. Since the 32-bit and
- // 64-bit only differ in the last field (reserved), this is safe to do.
- struct mach_header_64 header64;
- memcpy((void *)&header64, (const void *)&header, sizeof(header));
- header64.reserved = 0;
- current_header_ = &header64;
- current_header_size_ = sizeof(header); // 32-bit, not 64-bit
- current_header_offset_ = offset;
- offset += current_header_size_;
- bool result = WalkHeaderCore(offset, header.ncmds, swap);
- current_header_ = NULL;
- current_header_size_ = 0;
- current_header_offset_ = 0;
- return result;
- }
- bool MachoWalker::WalkHeader64AtOffset(off_t offset) {
- struct mach_header_64 header;
- if (!ReadBytes(&header, sizeof(header), offset))
- return false;
- bool swap = (header.magic == MH_CIGAM_64);
- if (swap)
- breakpad_swap_mach_header_64(&header, NXHostByteOrder());
- current_header_ = &header;
- current_header_size_ = sizeof(header);
- current_header_offset_ = offset;
- offset += current_header_size_;
- bool result = WalkHeaderCore(offset, header.ncmds, swap);
- current_header_ = NULL;
- current_header_size_ = 0;
- current_header_offset_ = 0;
- return result;
- }
- bool MachoWalker::WalkHeaderCore(off_t offset, uint32_t number_of_commands,
- bool swap) {
- for (uint32_t i = 0; i < number_of_commands; ++i) {
- struct load_command cmd;
- if (!ReadBytes(&cmd, sizeof(cmd), offset))
- return false;
- if (swap)
- swap_load_command(&cmd, NXHostByteOrder());
- // Call the user callback
- if (callback_ && !callback_(this, &cmd, offset, swap, callback_context_))
- break;
- offset += cmd.cmdsize;
- }
- return true;
- }
- } // namespace MacFileUtilities