blob: 2481c8ba46f81adcab90957e734203dc5e421b6e [file] [log] [blame]
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "vdex_file.h"
#include <memory>
#include "base/logging.h"
#include "base/unix_file/fd_file.h"
#include "dex_file.h"
namespace art {
constexpr uint8_t VdexFile::Header::kVdexMagic[4];
constexpr uint8_t VdexFile::Header::kVdexVersion[4];
bool VdexFile::Header::IsMagicValid() const {
return (memcmp(magic_, kVdexMagic, sizeof(kVdexMagic)) == 0);
}
bool VdexFile::Header::IsVersionValid() const {
return (memcmp(version_, kVdexVersion, sizeof(kVdexVersion)) == 0);
}
VdexFile::Header::Header(uint32_t number_of_dex_files,
uint32_t dex_size,
uint32_t verifier_deps_size,
uint32_t quickening_info_size)
: number_of_dex_files_(number_of_dex_files),
dex_size_(dex_size),
verifier_deps_size_(verifier_deps_size),
quickening_info_size_(quickening_info_size) {
memcpy(magic_, kVdexMagic, sizeof(kVdexMagic));
memcpy(version_, kVdexVersion, sizeof(kVdexVersion));
DCHECK(IsMagicValid());
DCHECK(IsVersionValid());
}
std::unique_ptr<VdexFile> VdexFile::Open(const std::string& vdex_filename,
bool writable,
bool low_4gb,
std::string* error_msg) {
if (!OS::FileExists(vdex_filename.c_str())) {
*error_msg = "File " + vdex_filename + " does not exist.";
return nullptr;
}
std::unique_ptr<File> vdex_file;
if (writable) {
vdex_file.reset(OS::OpenFileReadWrite(vdex_filename.c_str()));
} else {
vdex_file.reset(OS::OpenFileForReading(vdex_filename.c_str()));
}
if (vdex_file == nullptr) {
*error_msg = "Could not open file " + vdex_filename +
(writable ? " for read/write" : "for reading");
return nullptr;
}
int64_t vdex_length = vdex_file->GetLength();
if (vdex_length == -1) {
*error_msg = "Could not read the length of file " + vdex_filename;
return nullptr;
}
return Open(vdex_file->Fd(), vdex_length, vdex_filename, writable, low_4gb, error_msg);
}
std::unique_ptr<VdexFile> VdexFile::Open(int file_fd,
size_t vdex_length,
const std::string& vdex_filename,
bool writable,
bool low_4gb,
std::string* error_msg) {
std::unique_ptr<MemMap> mmap(MemMap::MapFile(vdex_length,
writable ? PROT_READ | PROT_WRITE : PROT_READ,
MAP_SHARED,
file_fd,
0 /* start offset */,
low_4gb,
vdex_filename.c_str(),
error_msg));
if (mmap == nullptr) {
*error_msg = "Failed to mmap file " + vdex_filename + " : " + *error_msg;
return nullptr;
}
std::unique_ptr<VdexFile> vdex(new VdexFile(mmap.release()));
if (!vdex->IsValid()) {
*error_msg = "Vdex file is not valid";
return nullptr;
}
*error_msg = "Success";
return vdex;
}
const uint8_t* VdexFile::GetNextDexFileData(const uint8_t* cursor) const {
DCHECK(cursor == nullptr || (cursor > Begin() && cursor <= End()));
if (cursor == nullptr) {
// Beginning of the iteration, return the first dex file if there is one.
return HasDexSection() ? DexBegin() : nullptr;
} else {
// Fetch the next dex file. Return null if there is none.
const uint8_t* data = cursor + reinterpret_cast<const DexFile::Header*>(cursor)->file_size_;
return (data == DexEnd()) ? nullptr : data;
}
}
} // namespace art