C++ DataExtractor::SetByteOrder方法代码示例

uint32_t Opcode::GetData(DataExtractor &data) const {
  uint32_t byte_size = GetByteSize();
  uint8_t swap_buf[8];
  const void *buf = nullptr;

  if (byte_size > 0) {
    if (!GetEndianSwap()) {
      if (m_type == Opcode::eType16_2) {
        // 32 bit thumb instruction, we need to sizzle this a bit
        swap_buf[0] = m_data.inst.bytes[2];
        swap_buf[1] = m_data.inst.bytes[3];
        swap_buf[2] = m_data.inst.bytes[0];
        swap_buf[3] = m_data.inst.bytes[1];
        buf = swap_buf;
      } else {
        buf = GetOpcodeDataBytes();
      }
    } else {
      switch (m_type) {
      case Opcode::eTypeInvalid:
        break;
      case Opcode::eType8:
        buf = GetOpcodeDataBytes();
        break;
      case Opcode::eType16:
        *(uint16_t *)swap_buf = llvm::ByteSwap_16(m_data.inst16);
        buf = swap_buf;
        break;
      case Opcode::eType16_2:
        swap_buf[0] = m_data.inst.bytes[1];
        swap_buf[1] = m_data.inst.bytes[0];
        swap_buf[2] = m_data.inst.bytes[3];
        swap_buf[3] = m_data.inst.bytes[2];
        buf = swap_buf;
        break;
      case Opcode::eType32:
        *(uint32_t *)swap_buf = llvm::ByteSwap_32(m_data.inst32);
        buf = swap_buf;
        break;
      case Opcode::eType64:
        *(uint32_t *)swap_buf = llvm::ByteSwap_64(m_data.inst64);
        buf = swap_buf;
        break;
      case Opcode::eTypeBytes:
        buf = GetOpcodeDataBytes();
        break;
      }
    }
  }
  if (buf != nullptr) {
    DataBufferSP buffer_sp;

    buffer_sp.reset(new DataBufferHeap(buf, byte_size));
    data.SetByteOrder(GetDataByteOrder());
    data.SetData(buffer_sp);
    return byte_size;
  }
  data.Clear();
  return 0;
}

size_t
Disassembler::ParseInstructions
(
    const ExecutionContext *exe_ctx,
    const AddressRange &range,
    DataExtractor& data
)
{
    Target *target = exe_ctx->target;

    const addr_t byte_size = range.GetByteSize();
    if (target == NULL || byte_size == 0 || !range.GetBaseAddress().IsValid())
        return 0;

    DataBufferHeap *heap_buffer = new DataBufferHeap (byte_size, '\0');
    DataBufferSP data_sp(heap_buffer);

    Error error;
    const size_t bytes_read = target->ReadMemory (range.GetBaseAddress(), heap_buffer->GetBytes(), heap_buffer->GetByteSize(), error);
    
    if (bytes_read > 0)
    {
        if (bytes_read != heap_buffer->GetByteSize())
            heap_buffer->SetByteSize (bytes_read);

        data.SetData(data_sp);
        if (exe_ctx->process)
        {
            data.SetByteOrder(exe_ctx->process->GetByteOrder());
            data.SetAddressByteSize(exe_ctx->process->GetAddressByteSize());
        }
        else
        {
            data.SetByteOrder(target->GetArchitecture().GetDefaultEndian());
            data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
        }
        return DecodeInstructions (data, 0, UINT32_MAX);
    }

    return 0;
}

uint32_t
Opcode::GetData (DataExtractor &data, lldb::AddressClass address_class) const
{
    uint32_t byte_size = GetByteSize ();
    
    DataBufferSP buffer_sp;
    if (byte_size > 0)
    {
        switch (m_type)
        {
            case Opcode::eTypeInvalid:
                break;
                
            case Opcode::eType8:    buffer_sp.reset (new DataBufferHeap (&m_data.inst8,  byte_size)); break;
            case Opcode::eType16:   buffer_sp.reset (new DataBufferHeap (&m_data.inst16, byte_size)); break;
            case Opcode::eType32:
                {
                    // The only thing that uses eAddressClassCodeAlternateISA currently
                    // is Thumb. If this ever changes, we will need to pass in more
                    // information like an additional "const ArchSpec &arch". For now
                    // this will do
                    if (address_class == eAddressClassCodeAlternateISA)
                    {
                        // 32 bit thumb instruction, we need to sizzle this a bit
                        uint8_t buf[4];
                        buf[0] = m_data.inst.bytes[2];
                        buf[1] = m_data.inst.bytes[3];
                        buf[2] = m_data.inst.bytes[0];
                        buf[3] = m_data.inst.bytes[1];
                        buffer_sp.reset (new DataBufferHeap (buf, byte_size));
                        break;
                    }
                    buffer_sp.reset (new DataBufferHeap (&m_data.inst32, byte_size));
                }
                break;

            case Opcode::eType64:   buffer_sp.reset (new DataBufferHeap (&m_data.inst64, byte_size)); break;
            case Opcode::eTypeBytes:buffer_sp.reset (new DataBufferHeap (GetOpcodeBytes(), byte_size)); break;
                break;
        }
    }
    
    if (buffer_sp)
    {
        data.SetByteOrder(GetDataByteOrder());
        data.SetData (buffer_sp);
        return byte_size;
    }
    data.Clear();
    return 0;
}

size_t
ObjectFilePECOFF::GetModuleSpecifications (const lldb_private::FileSpec& file,
                                           lldb::DataBufferSP& data_sp,
                                           lldb::offset_t data_offset,
                                           lldb::offset_t file_offset,
                                           lldb::offset_t length,
                                           lldb_private::ModuleSpecList &specs)
{
    const size_t initial_count = specs.GetSize();

    if (ObjectFilePECOFF::MagicBytesMatch(data_sp))
    {
        DataExtractor data;
        data.SetData(data_sp, data_offset, length);
        data.SetByteOrder(eByteOrderLittle);

        dos_header_t dos_header;
        coff_header_t coff_header;

        if (ParseDOSHeader(data, dos_header))
        {
            lldb::offset_t offset = dos_header.e_lfanew;
            uint32_t pe_signature = data.GetU32(&offset);
            if (pe_signature != IMAGE_NT_SIGNATURE)
                return false;
            if (ParseCOFFHeader(data, &offset, coff_header))
            {
                ArchSpec spec;
                if (coff_header.machine == MachineAmd64)
                {
                    spec.SetTriple("x86_64-pc-windows");
                    specs.Append(ModuleSpec(file, spec));
                }
                else if (coff_header.machine == MachineX86)
                {
                    spec.SetTriple("i386-pc-windows");
                    specs.Append(ModuleSpec(file, spec));
                    spec.SetTriple("i686-pc-windows");
                    specs.Append(ModuleSpec(file, spec));
                }
            }
        }
    }

    return specs.GetSize() - initial_count;
}

size_t
Section::MemoryMapSectionDataFromObjectFile(const ObjectFile* objfile, DataExtractor& section_data) const
{
    if (objfile == NULL)
        return 0;

    const FileSpec& file = objfile->GetFileSpec();

    if (file)
    {
        size_t section_file_size = GetFileSize();
        if (section_file_size > 0)
        {
            off_t section_file_offset = GetFileOffset() + objfile->GetOffset();
            DataBufferSP section_data_sp(file.MemoryMapFileContents(section_file_offset, section_file_size));
            section_data.SetByteOrder(objfile->GetByteOrder());
            section_data.SetAddressByteSize(objfile->GetAddressByteSize());
            return section_data.SetData (section_data_sp);
        }
    }
    return 0;
}

Error
Value::GetValueAsData (ExecutionContext *exe_ctx,
                       DataExtractor &data,
                       uint32_t data_offset,
                       Module *module)
{
    data.Clear();

    Error error;
    lldb::addr_t address = LLDB_INVALID_ADDRESS;
    AddressType address_type = eAddressTypeFile;
    Address file_so_addr;
    const CompilerType &ast_type = GetCompilerType();
    switch (m_value_type)
    {
    case eValueTypeVector:
        if (ast_type.IsValid())
            data.SetAddressByteSize (ast_type.GetPointerByteSize());
        else
            data.SetAddressByteSize(sizeof(void *));
        data.SetData(m_vector.bytes, m_vector.length, m_vector.byte_order);
        break;

    case eValueTypeScalar:
        {
            data.SetByteOrder (endian::InlHostByteOrder());
            if (ast_type.IsValid())
                data.SetAddressByteSize (ast_type.GetPointerByteSize());
            else
                data.SetAddressByteSize(sizeof(void *));

            uint32_t limit_byte_size = UINT32_MAX;
            
            if (ast_type.IsValid() && ast_type.IsScalarType())
            {
                uint64_t type_encoding_count = 0;
                lldb::Encoding type_encoding = ast_type.GetEncoding(type_encoding_count);
                
                if (type_encoding == eEncodingUint || type_encoding == eEncodingSint)
                    limit_byte_size = ast_type.GetByteSize(exe_ctx ? exe_ctx->GetBestExecutionContextScope() : nullptr);
            }
            
            if (m_value.GetData (data, limit_byte_size))
                return error;   // Success;
            
            error.SetErrorStringWithFormat("extracting data from value failed");
            break;
        }
    case eValueTypeLoadAddress:
        if (exe_ctx == NULL)
        {
            error.SetErrorString ("can't read load address (no execution context)");
        }
        else 
        {
            Process *process = exe_ctx->GetProcessPtr();
            if (process == NULL || !process->IsAlive())
            {
                Target *target = exe_ctx->GetTargetPtr();
                if (target)
                {
                    // Allow expressions to run and evaluate things when the target
                    // has memory sections loaded. This allows you to use "target modules load"
                    // to load your executable and any shared libraries, then execute
                    // commands where you can look at types in data sections.
                    const SectionLoadList &target_sections = target->GetSectionLoadList();
                    if (!target_sections.IsEmpty())
                    {
                        address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
                        if (target_sections.ResolveLoadAddress(address, file_so_addr))
                        {
                            address_type = eAddressTypeLoad;
                            data.SetByteOrder(target->GetArchitecture().GetByteOrder());
                            data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
                        }
                        else
                            address = LLDB_INVALID_ADDRESS;
                    }
//                    else
//                    {
//                        ModuleSP exe_module_sp (target->GetExecutableModule());
//                        if (exe_module_sp)
//                        {
//                            address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
//                            if (address != LLDB_INVALID_ADDRESS)
//                            {
//                                if (exe_module_sp->ResolveFileAddress(address, file_so_addr))
//                                {
//                                    data.SetByteOrder(target->GetArchitecture().GetByteOrder());
//                                    data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
//                                    address_type = eAddressTypeFile;
//                                }
//                                else
//                                {
//                                    address = LLDB_INVALID_ADDRESS;
//                                }
//                            }
//                        }
//                    }
                }
//.........这里部分代码省略.........

static bool
SkinnyMachOFileContainsArchAndUUID
(
    const FileSpec &file_spec,
    const ArchSpec *arch,
    const lldb_private::UUID *uuid,   // the UUID we are looking for
    off_t file_offset,
    DataExtractor& data,
    uint32_t data_offset,
    const uint32_t magic
)
{
    assert(magic == HeaderMagic32 || magic == HeaderMagic32Swapped || magic == HeaderMagic64 || magic == HeaderMagic64Swapped);
    if (magic == HeaderMagic32 || magic == HeaderMagic64)
        data.SetByteOrder (lldb::endian::InlHostByteOrder());
    else if (lldb::endian::InlHostByteOrder() == eByteOrderBig)
        data.SetByteOrder (eByteOrderLittle);
    else
        data.SetByteOrder (eByteOrderBig);

    uint32_t i;
    const uint32_t cputype      = data.GetU32(&data_offset);    // cpu specifier
    const uint32_t cpusubtype   = data.GetU32(&data_offset);    // machine specifier
    data_offset+=4; // Skip mach file type
    const uint32_t ncmds        = data.GetU32(&data_offset);    // number of load commands
    const uint32_t sizeofcmds   = data.GetU32(&data_offset);    // the size of all the load commands
    data_offset+=4; // Skip flags

    // Check the architecture if we have a valid arch pointer
    if (arch)
    {
        ArchSpec file_arch(eArchTypeMachO, cputype, cpusubtype);

        if (file_arch != *arch)
            return false;
    }

    // The file exists, and if a valid arch pointer was passed in we know
    // if already matches, so we can return if we aren't looking for a specific
    // UUID
    if (uuid == NULL)
        return true;

    if (magic == HeaderMagic64Swapped || magic == HeaderMagic64)
        data_offset += 4;   // Skip reserved field for in mach_header_64

    // Make sure we have enough data for all the load commands
    if (magic == HeaderMagic64Swapped || magic == HeaderMagic64)
    {
        if (data.GetByteSize() < sizeof(struct mach_header_64) + sizeofcmds)
        {
            DataBufferSP data_buffer_sp (file_spec.ReadFileContents (file_offset, sizeof(struct mach_header_64) + sizeofcmds));
            data.SetData (data_buffer_sp);
        }
    }
    else
    {
        if (data.GetByteSize() < sizeof(struct mach_header) + sizeofcmds)
        {
            DataBufferSP data_buffer_sp (file_spec.ReadFileContents (file_offset, sizeof(struct mach_header) + sizeofcmds));
            data.SetData (data_buffer_sp);
        }
    }

    for (i=0; i<ncmds; i++)
    {
        const uint32_t cmd_offset = data_offset;    // Save this data_offset in case parsing of the segment goes awry!
        uint32_t cmd        = data.GetU32(&data_offset);
        uint32_t cmd_size   = data.GetU32(&data_offset);
        if (cmd == LoadCommandUUID)
        {
            lldb_private::UUID file_uuid (data.GetData(&data_offset, 16), 16);
            if (file_uuid == *uuid)
                return true;

            // Emit some warning messages since the UUIDs do not match!
            char path_buf[PATH_MAX];
            path_buf[0] = '\0';
            const char *path = file_spec.GetPath(path_buf, PATH_MAX) ? path_buf
                                                                     : file_spec.GetFilename().AsCString();
            Host::SystemLog (Host::eSystemLogWarning, 
                             "warning: UUID mismatch detected between binary and:\n\t'%s'\n", 
                             path);
            return false;
        }
        data_offset = cmd_offset + cmd_size;
    }
    return false;
}

bool
UniversalMachOFileContainsArchAndUUID
(
    const FileSpec &file_spec,
    const ArchSpec *arch,
    const lldb_private::UUID *uuid,
    off_t file_offset,
    DataExtractor& data,
    uint32_t data_offset,
    const uint32_t magic
)
{
    assert(magic == UniversalMagic || magic == UniversalMagicSwapped);

    // Universal mach-o files always have their headers encoded as BIG endian
    data.SetByteOrder(eByteOrderBig);

    uint32_t i;
    const uint32_t nfat_arch = data.GetU32(&data_offset);   // number of structs that follow
    const uint32_t fat_header_and_arch_size = sizeof(struct fat_header) + nfat_arch * sizeof(struct fat_arch);
    if (data.GetByteSize() < fat_header_and_arch_size)
    {
        DataBufferSP data_buffer_sp (file_spec.ReadFileContents (file_offset, fat_header_and_arch_size));
        data.SetData (data_buffer_sp);
    }

    for (i=0; i<nfat_arch; i++)
    {
        cpu_type_t      arch_cputype        = data.GetU32(&data_offset);    // cpu specifier (int)
        cpu_subtype_t   arch_cpusubtype     = data.GetU32(&data_offset);    // machine specifier (int)
        uint32_t        arch_offset         = data.GetU32(&data_offset);    // file offset to this object file
    //  uint32_t        arch_size           = data.GetU32(&data_offset);    // size of this object file
    //  uint32_t        arch_align          = data.GetU32(&data_offset);    // alignment as a power of 2
        data_offset += 8;   // Skip size and align as we don't need those
        // Only process this slice if the cpu type/subtype matches
        if (arch)
        {
            ArchSpec fat_arch(eArchTypeMachO, arch_cputype, arch_cpusubtype);
            if (fat_arch != *arch)
                continue;
        }

        // Create a buffer with only the arch slice date in it
        DataExtractor arch_data;
        DataBufferSP data_buffer_sp (file_spec.ReadFileContents (file_offset + arch_offset, 0x1000));
        arch_data.SetData(data_buffer_sp);
        uint32_t arch_data_offset = 0;
        uint32_t arch_magic = arch_data.GetU32(&arch_data_offset);

        switch (arch_magic)
        {
        case HeaderMagic32:
        case HeaderMagic32Swapped:
        case HeaderMagic64:
        case HeaderMagic64Swapped:
            if (SkinnyMachOFileContainsArchAndUUID (file_spec, arch, uuid, file_offset + arch_offset, arch_data, arch_data_offset, arch_magic))
                return true;
            break;
        }
    }
    return false;
}

static bool
SkinnyMachOFileContainsArchAndUUID
(
    const FileSpec &file_spec,
    const ArchSpec *arch,
    const lldb_private::UUID *uuid,   // the UUID we are looking for
    off_t file_offset,
    DataExtractor& data,
    lldb::offset_t data_offset,
    const uint32_t magic
)
{
    assert(magic == HeaderMagic32 || magic == HeaderMagic32Swapped || magic == HeaderMagic64 || magic == HeaderMagic64Swapped);
    if (magic == HeaderMagic32 || magic == HeaderMagic64)
        data.SetByteOrder (lldb::endian::InlHostByteOrder());
    else if (lldb::endian::InlHostByteOrder() == eByteOrderBig)
        data.SetByteOrder (eByteOrderLittle);
    else
        data.SetByteOrder (eByteOrderBig);

    uint32_t i;
    const uint32_t cputype      = data.GetU32(&data_offset);    // cpu specifier
    const uint32_t cpusubtype   = data.GetU32(&data_offset);    // machine specifier
    data_offset+=4; // Skip mach file type
    const uint32_t ncmds        = data.GetU32(&data_offset);    // number of load commands
    const uint32_t sizeofcmds   = data.GetU32(&data_offset);    // the size of all the load commands
    data_offset+=4; // Skip flags

    // Check the architecture if we have a valid arch pointer
    if (arch)
    {
        ArchSpec file_arch(eArchTypeMachO, cputype, cpusubtype);

        if (!file_arch.IsCompatibleMatch(*arch))
            return false;
    }

    // The file exists, and if a valid arch pointer was passed in we know
    // if already matches, so we can return if we aren't looking for a specific
    // UUID
    if (uuid == NULL)
        return true;

    if (magic == HeaderMagic64Swapped || magic == HeaderMagic64)
        data_offset += 4;   // Skip reserved field for in mach_header_64

    // Make sure we have enough data for all the load commands
    if (magic == HeaderMagic64Swapped || magic == HeaderMagic64)
    {
        if (data.GetByteSize() < sizeof(struct mach_header_64) + sizeofcmds)
        {
            DataBufferSP data_buffer_sp (file_spec.ReadFileContents (file_offset, sizeof(struct mach_header_64) + sizeofcmds));
            data.SetData (data_buffer_sp);
        }
    }
    else
    {
        if (data.GetByteSize() < sizeof(struct mach_header) + sizeofcmds)
        {
            DataBufferSP data_buffer_sp (file_spec.ReadFileContents (file_offset, sizeof(struct mach_header) + sizeofcmds));
            data.SetData (data_buffer_sp);
        }
    }

    for (i=0; i<ncmds; i++)
    {
        const lldb::offset_t cmd_offset = data_offset;    // Save this data_offset in case parsing of the segment goes awry!
        uint32_t cmd        = data.GetU32(&data_offset);
        uint32_t cmd_size   = data.GetU32(&data_offset);
        if (cmd == LoadCommandUUID)
        {
            lldb_private::UUID file_uuid (data.GetData(&data_offset, 16), 16);
            if (file_uuid == *uuid)
                return true;
            return false;
        }
        data_offset = cmd_offset + cmd_size;
    }
    return false;
}

Error
Value::GetValueAsData (ExecutionContext *exe_ctx, 
                       clang::ASTContext *ast_context, 
                       DataExtractor &data, 
                       uint32_t data_offset,
                       Module *module)
{
    data.Clear();

    Error error;
    lldb::addr_t address = LLDB_INVALID_ADDRESS;
    AddressType address_type = eAddressTypeFile;
    Address file_so_addr;
    switch (m_value_type)
    {
    default:
        error.SetErrorStringWithFormat("invalid value type %i", m_value_type);
        break;

    case eValueTypeScalar:
        data.SetByteOrder (lldb::endian::InlHostByteOrder());
        if (m_context_type == eContextTypeClangType && ast_context)
        {
            uint32_t ptr_bit_width = ClangASTType::GetClangTypeBitWidth (ast_context, 
                                                                     ClangASTContext::GetVoidPtrType(ast_context, false));
            uint32_t ptr_byte_size = (ptr_bit_width + 7) / 8;
            data.SetAddressByteSize (ptr_byte_size);
        }
        else
            data.SetAddressByteSize(sizeof(void *));
        if (m_value.GetData (data))
            return error;   // Success;
        error.SetErrorStringWithFormat("extracting data from value failed");
        break;

    case eValueTypeLoadAddress:
        if (exe_ctx == NULL)
        {
            error.SetErrorString ("can't read load address (no execution context)");
        }
        else 
        {
            Process *process = exe_ctx->GetProcessPtr();
            if (process == NULL)
            {
                error.SetErrorString ("can't read load address (invalid process)");
            }
            else
            {
                address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
                address_type = eAddressTypeLoad;
                data.SetByteOrder(process->GetTarget().GetArchitecture().GetByteOrder());
                data.SetAddressByteSize(process->GetTarget().GetArchitecture().GetAddressByteSize());
            }
        }
        break;

    case eValueTypeFileAddress:
        if (exe_ctx == NULL)
        {
            error.SetErrorString ("can't read file address (no execution context)");
        }
        else if (exe_ctx->GetTargetPtr() == NULL)
        {
            error.SetErrorString ("can't read file address (invalid target)");
        }
        else
        {
            address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
            if (address == LLDB_INVALID_ADDRESS)
            {
                error.SetErrorString ("invalid file address");
            }
            else
            {
                if (module == NULL)
                {
                    // The only thing we can currently lock down to a module so that
                    // we can resolve a file address, is a variable.
                    Variable *variable = GetVariable();
                    if (variable)
                    {
                        SymbolContext var_sc;
                        variable->CalculateSymbolContext(&var_sc);
                        module = var_sc.module_sp.get();
                    }
                }
                
                if (module)
                {
                    bool resolved = false;
                    ObjectFile *objfile = module->GetObjectFile();
                    if (objfile)
                    {
                        Address so_addr(address, objfile->GetSectionList());
                        addr_t load_address = so_addr.GetLoadAddress (exe_ctx->GetTargetPtr());
                        bool process_launched_and_stopped = exe_ctx->GetProcessPtr()
                            ? StateIsStoppedState(exe_ctx->GetProcessPtr()->GetState(), true /* must_exist */)
                            : false;
                        // Don't use the load address if the process has exited.
//.........这里部分代码省略.........

bool
DynamicLoaderMacOSXDYLD::ReadAllImageInfosStructure ()
{
    std::lock_guard<std::recursive_mutex> guard(m_mutex);

    // the all image infos is already valid for this process stop ID
    if (m_process->GetStopID() == m_dyld_all_image_infos_stop_id)
        return true;

    m_dyld_all_image_infos.Clear();
    if (m_dyld_all_image_infos_addr != LLDB_INVALID_ADDRESS)
    {
        ByteOrder byte_order = m_process->GetTarget().GetArchitecture().GetByteOrder();
        uint32_t addr_size = 4;
        if (m_dyld_all_image_infos_addr > UINT32_MAX)
            addr_size = 8;

        uint8_t buf[256];
        DataExtractor data (buf, sizeof(buf), byte_order, addr_size);
        lldb::offset_t offset = 0;

        const size_t count_v2 =  sizeof (uint32_t) + // version
                                 sizeof (uint32_t) + // infoArrayCount
                                 addr_size +         // infoArray
                                 addr_size +         // notification
                                 addr_size +         // processDetachedFromSharedRegion + libSystemInitialized + pad
                                 addr_size;          // dyldImageLoadAddress
        const size_t count_v11 = count_v2 +
                                 addr_size +         // jitInfo
                                 addr_size +         // dyldVersion
                                 addr_size +         // errorMessage
                                 addr_size +         // terminationFlags
                                 addr_size +         // coreSymbolicationShmPage
                                 addr_size +         // systemOrderFlag
                                 addr_size +         // uuidArrayCount
                                 addr_size +         // uuidArray
                                 addr_size +         // dyldAllImageInfosAddress
                                 addr_size +         // initialImageCount
                                 addr_size +         // errorKind
                                 addr_size +         // errorClientOfDylibPath
                                 addr_size +         // errorTargetDylibPath
                                 addr_size;          // errorSymbol
        const size_t count_v13 = count_v11 +
                                 addr_size +         // sharedCacheSlide
                                 sizeof (uuid_t);    // sharedCacheUUID
        UNUSED_IF_ASSERT_DISABLED(count_v13);
        assert (sizeof (buf) >= count_v13);

        Error error;
        if (m_process->ReadMemory (m_dyld_all_image_infos_addr, buf, 4, error) == 4)
        {
            m_dyld_all_image_infos.version = data.GetU32(&offset);
            // If anything in the high byte is set, we probably got the byte 
            // order incorrect (the process might not have it set correctly 
            // yet due to attaching to a program without a specified file).
            if (m_dyld_all_image_infos.version & 0xff000000)
            {
                // We have guessed the wrong byte order. Swap it and try
                // reading the version again.
                if (byte_order == eByteOrderLittle)
                    byte_order = eByteOrderBig;
                else
                    byte_order = eByteOrderLittle;

                data.SetByteOrder (byte_order);
                offset = 0;
                m_dyld_all_image_infos.version = data.GetU32(&offset);
            }
        }
        else
        {
            return false;
        }

        const size_t count = (m_dyld_all_image_infos.version >= 11) ? count_v11 : count_v2;

        const size_t bytes_read = m_process->ReadMemory (m_dyld_all_image_infos_addr, buf, count, error);
        if (bytes_read == count)
        {
            offset = 0;
            m_dyld_all_image_infos.version = data.GetU32(&offset);
            m_dyld_all_image_infos.dylib_info_count = data.GetU32(&offset);
            m_dyld_all_image_infos.dylib_info_addr = data.GetPointer(&offset);
            m_dyld_all_image_infos.notification = data.GetPointer(&offset);
            m_dyld_all_image_infos.processDetachedFromSharedRegion = data.GetU8(&offset);
            m_dyld_all_image_infos.libSystemInitialized = data.GetU8(&offset);
            // Adjust for padding.
            offset += addr_size - 2;
            m_dyld_all_image_infos.dyldImageLoadAddress = data.GetPointer(&offset);
            if (m_dyld_all_image_infos.version >= 11)
            {
                offset += addr_size * 8;
                uint64_t dyld_all_image_infos_addr = data.GetPointer(&offset);

                // When we started, we were given the actual address of the all_image_infos
                // struct (probably via TASK_DYLD_INFO) in memory - this address is stored in
                // m_dyld_all_image_infos_addr and is the most accurate address we have.

                // We read the dyld_all_image_infos struct from memory; it contains its own address.
                // If the address in the struct does not match the actual address,
//.........这里部分代码省略.........