//
// Copyright (C) 2015 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 "update_engine/payload_generator/ab_generator.h"
#include <algorithm>
#include <utility>
#include <base/strings/stringprintf.h>
#include "update_engine/common/hash_calculator.h"
#include "update_engine/common/utils.h"
#include "update_engine/payload_consumer/payload_constants.h"
#include "update_engine/payload_generator/annotated_operation.h"
#include "update_engine/payload_generator/bzip.h"
#include "update_engine/payload_generator/delta_diff_generator.h"
#include "update_engine/payload_generator/delta_diff_utils.h"
using chromeos_update_engine::diff_utils::IsAReplaceOperation;
using std::string;
using std::vector;
namespace chromeos_update_engine {
bool ABGenerator::GenerateOperations(const PayloadGenerationConfig& config,
const PartitionConfig& old_part,
const PartitionConfig& new_part,
BlobFileWriter* blob_file,
vector<AnnotatedOperation>* aops) {
TEST_AND_RETURN_FALSE(old_part.name == new_part.name);
ssize_t hard_chunk_blocks =
(config.hard_chunk_size == -1
? -1
: config.hard_chunk_size / config.block_size);
size_t soft_chunk_blocks = config.soft_chunk_size / config.block_size;
aops->clear();
TEST_AND_RETURN_FALSE(diff_utils::DeltaReadPartition(aops,
old_part,
new_part,
hard_chunk_blocks,
soft_chunk_blocks,
config.version,
blob_file));
LOG(INFO) << "done reading " << new_part.name;
SortOperationsByDestination(aops);
// Use the soft_chunk_size when merging operations to prevent merging all
// the operations into a huge one if there's no hard limit.
size_t merge_chunk_blocks = soft_chunk_blocks;
if (hard_chunk_blocks != -1 &&
static_cast<size_t>(hard_chunk_blocks) < soft_chunk_blocks) {
merge_chunk_blocks = hard_chunk_blocks;
}
LOG(INFO) << "Merging " << aops->size() << " operations.";
TEST_AND_RETURN_FALSE(MergeOperations(
aops, config.version, merge_chunk_blocks, new_part.path, blob_file));
LOG(INFO) << aops->size() << " operations after merge.";
if (config.version.minor >= kOpSrcHashMinorPayloadVersion)
TEST_AND_RETURN_FALSE(AddSourceHash(aops, old_part.path));
return true;
}
void ABGenerator::SortOperationsByDestination(
vector<AnnotatedOperation>* aops) {
sort(aops->begin(), aops->end(), diff_utils::CompareAopsByDestination);
}
bool ABGenerator::FragmentOperations(const PayloadVersion& version,
vector<AnnotatedOperation>* aops,
const string& target_part_path,
BlobFileWriter* blob_file) {
vector<AnnotatedOperation> fragmented_aops;
for (const AnnotatedOperation& aop : *aops) {
// Only do split if the operation has more than one dst extents.
if (aop.op.dst_extents_size() > 1) {
if (aop.op.type() == InstallOperation::SOURCE_COPY) {
TEST_AND_RETURN_FALSE(SplitSourceCopy(aop, &fragmented_aops));
continue;
}
if (IsAReplaceOperation(aop.op.type())) {
TEST_AND_RETURN_FALSE(SplitAReplaceOp(
version, aop, target_part_path, &fragmented_aops, blob_file));
continue;
}
}
fragmented_aops.push_back(aop);
}
*aops = std::move(fragmented_aops);
return true;
}
bool ABGenerator::SplitSourceCopy(const AnnotatedOperation& original_aop,
vector<AnnotatedOperation>* result_aops) {
InstallOperation original_op = original_aop.op;
TEST_AND_RETURN_FALSE(original_op.type() == InstallOperation::SOURCE_COPY);
// Keeps track of the index of curr_src_ext.
int curr_src_ext_index = 0;
Extent curr_src_ext = original_op.src_extents(curr_src_ext_index);
for (int i = 0; i < original_op.dst_extents_size(); i++) {
const Extent& dst_ext = original_op.dst_extents(i);
// The new operation which will have only one dst extent.
InstallOperation new_op;
uint64_t blocks_left = dst_ext.num_blocks();
while (blocks_left > 0) {
if (curr_src_ext.num_blocks() <= blocks_left) {
// If the curr_src_ext is smaller than dst_ext, add it.
blocks_left -= curr_src_ext.num_blocks();
*(new_op.add_src_extents()) = curr_src_ext;
if (curr_src_ext_index + 1 < original_op.src_extents().size()) {
curr_src_ext = original_op.src_extents(++curr_src_ext_index);
} else {
break;
}
} else {
// Split src_exts that are bigger than the dst_ext we're dealing with.
Extent first_ext;
first_ext.set_num_blocks(blocks_left);
first_ext.set_start_block(curr_src_ext.start_block());
*(new_op.add_src_extents()) = first_ext;
// Keep the second half of the split op.
curr_src_ext.set_num_blocks(curr_src_ext.num_blocks() - blocks_left);
curr_src_ext.set_start_block(curr_src_ext.start_block() + blocks_left);
blocks_left -= first_ext.num_blocks();
}
}
// Fix up our new operation and add it to the results.
new_op.set_type(InstallOperation::SOURCE_COPY);
*(new_op.add_dst_extents()) = dst_ext;
AnnotatedOperation new_aop;
new_aop.op = new_op;
new_aop.name = base::StringPrintf("%s:%d", original_aop.name.c_str(), i);
result_aops->push_back(new_aop);
}
if (curr_src_ext_index != original_op.src_extents().size() - 1) {
LOG(FATAL) << "Incorrectly split SOURCE_COPY operation. Did not use all "
<< "source extents.";
}
return true;
}
bool ABGenerator::SplitAReplaceOp(const PayloadVersion& version,
const AnnotatedOperation& original_aop,
const string& target_part_path,
vector<AnnotatedOperation>* result_aops,
BlobFileWriter* blob_file) {
InstallOperation original_op = original_aop.op;
TEST_AND_RETURN_FALSE(IsAReplaceOperation(original_op.type()));
const bool is_replace = original_op.type() == InstallOperation::REPLACE;
uint64_t data_offset = original_op.data_offset();
for (int i = 0; i < original_op.dst_extents_size(); i++) {
const Extent& dst_ext = original_op.dst_extents(i);
// Make a new operation with only one dst extent.
InstallOperation new_op;
*(new_op.add_dst_extents()) = dst_ext;
uint64_t data_size = dst_ext.num_blocks() * kBlockSize;
// If this is a REPLACE, attempt to reuse portions of the existing blob.
if (is_replace) {
new_op.set_type(InstallOperation::REPLACE);
new_op.set_data_length(data_size);
new_op.set_data_offset(data_offset);
data_offset += data_size;
}
AnnotatedOperation new_aop;
new_aop.op = new_op;
new_aop.name = base::StringPrintf("%s:%d", original_aop.name.c_str(), i);
TEST_AND_RETURN_FALSE(
AddDataAndSetType(&new_aop, version, target_part_path, blob_file));
result_aops->push_back(new_aop);
}
return true;
}
bool ABGenerator::MergeOperations(vector<AnnotatedOperation>* aops,
const PayloadVersion& version,
size_t chunk_blocks,
const string& target_part_path,
BlobFileWriter* blob_file) {
vector<AnnotatedOperation> new_aops;
for (const AnnotatedOperation& curr_aop : *aops) {
if (new_aops.empty()) {
new_aops.push_back(curr_aop);
continue;
}
AnnotatedOperation& last_aop = new_aops.back();
bool last_is_a_replace = IsAReplaceOperation(last_aop.op.type());
if (last_aop.op.dst_extents_size() <= 0 ||
curr_aop.op.dst_extents_size() <= 0) {
new_aops.push_back(curr_aop);
continue;
}
uint32_t last_dst_idx = last_aop.op.dst_extents_size() - 1;
uint32_t last_end_block =
last_aop.op.dst_extents(last_dst_idx).start_block() +
last_aop.op.dst_extents(last_dst_idx).num_blocks();
uint32_t curr_start_block = curr_aop.op.dst_extents(0).start_block();
uint32_t combined_block_count =
last_aop.op.dst_extents(last_dst_idx).num_blocks() +
curr_aop.op.dst_extents(0).num_blocks();
bool is_a_replace = IsAReplaceOperation(curr_aop.op.type());
bool is_delta_op = curr_aop.op.type() == InstallOperation::SOURCE_COPY;
if (((is_delta_op && (last_aop.op.type() == curr_aop.op.type())) ||
(is_a_replace && last_is_a_replace)) &&
last_end_block == curr_start_block &&
combined_block_count <= chunk_blocks) {
// If the operations have the same type (which is a type that we can
// merge), are contiguous, are fragmented to have one destination extent,
// and their combined block count would be less than chunk size, merge
// them.
last_aop.name = base::StringPrintf(
"%s,%s", last_aop.name.c_str(), curr_aop.name.c_str());
if (is_delta_op) {
ExtendExtents(last_aop.op.mutable_src_extents(),
curr_aop.op.src_extents());
}
ExtendExtents(last_aop.op.mutable_dst_extents(),
curr_aop.op.dst_extents());
// Set the data length to zero so we know to add the blob later.
if (is_a_replace)
last_aop.op.set_data_length(0);
} else {
// Otherwise just include the extent as is.
new_aops.push_back(curr_aop);
}
}
// Set the blobs for REPLACE/REPLACE_BZ/REPLACE_XZ operations that have been
// merged.
for (AnnotatedOperation& curr_aop : new_aops) {
if (curr_aop.op.data_length() == 0 &&
IsAReplaceOperation(curr_aop.op.type())) {
TEST_AND_RETURN_FALSE(
AddDataAndSetType(&curr_aop, version, target_part_path, blob_file));
}
}
*aops = new_aops;
return true;
}
bool ABGenerator::AddDataAndSetType(AnnotatedOperation* aop,
const PayloadVersion& version,
const string& target_part_path,
BlobFileWriter* blob_file) {
TEST_AND_RETURN_FALSE(IsAReplaceOperation(aop->op.type()));
vector<Extent> dst_extents;
ExtentsToVector(aop->op.dst_extents(), &dst_extents);
brillo::Blob data(utils::BlocksInExtents(dst_extents) * kBlockSize);
TEST_AND_RETURN_FALSE(utils::ReadExtents(
target_part_path, dst_extents, &data, data.size(), kBlockSize));
brillo::Blob blob;
InstallOperation::Type op_type;
TEST_AND_RETURN_FALSE(
diff_utils::GenerateBestFullOperation(data, version, &blob, &op_type));
// If the operation doesn't point to a data blob or points to a data blob of
// a different type then we add it.
if (aop->op.type() != op_type || aop->op.data_length() != blob.size()) {
aop->op.set_type(op_type);
aop->SetOperationBlob(blob, blob_file);
}
return true;
}
bool ABGenerator::AddSourceHash(vector<AnnotatedOperation>* aops,
const string& source_part_path) {
for (AnnotatedOperation& aop : *aops) {
if (aop.op.src_extents_size() == 0)
continue;
vector<Extent> src_extents;
ExtentsToVector(aop.op.src_extents(), &src_extents);
brillo::Blob src_data, src_hash;
uint64_t src_length =
aop.op.has_src_length()
? aop.op.src_length()
: utils::BlocksInExtents(aop.op.src_extents()) * kBlockSize;
TEST_AND_RETURN_FALSE(utils::ReadExtents(
source_part_path, src_extents, &src_data, src_length, kBlockSize));
TEST_AND_RETURN_FALSE(HashCalculator::RawHashOfData(src_data, &src_hash));
aop.op.set_src_sha256_hash(src_hash.data(), src_hash.size());
}
return true;
}
} // namespace chromeos_update_engine