blob: 2accf1ef3156247a25156d16294e388354d63e2c [file] [log] [blame]
// 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
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
#include <string>
#include <vector>
#include <base/macros.h>
#include <brillo/secure_blob.h>
#include "update_engine/payload_consumer/payload_constants.h"
#include "update_engine/payload_generator/blob_file_writer.h"
#include "update_engine/payload_generator/extent_utils.h"
#include "update_engine/payload_generator/filesystem_interface.h"
#include "update_engine/payload_generator/operations_generator.h"
#include "update_engine/payload_generator/payload_generation_config.h"
#include "update_engine/update_metadata.pb.h"
namespace chromeos_update_engine {
// The ABGenerator is an operations generator that generates payloads using the
// A-to-B operations SOURCE_COPY and SOURCE_BSDIFF introduced in the payload
// minor version 2 format.
class ABGenerator : public OperationsGenerator {
ABGenerator() = default;
// Generate the update payload operations for the given partition using
// SOURCE_* operations, used for generating deltas for the minor version
// kSourceMinorPayloadVersion. This function will generate operations in the
// partition that will read blocks from the source partition in random order
// and write the new image on the target partition, also possibly in random
// order. The operations are stored in |aops| and should be executed in that
// order. All the offsets in the operations reference the data written to
// |blob_file|.
bool GenerateOperations(const PayloadGenerationConfig& config,
const PartitionConfig& old_part,
const PartitionConfig& new_part,
BlobFileWriter* blob_file,
std::vector<AnnotatedOperation>* aops) override;
// Split the operations in the vector of AnnotatedOperations |aops| such that
// for every operation there is only one dst extent and updates |aops| with
// the new list of operations. All kinds of operations are fragmented except
// |target_part_path| is the filename of the new image, where the destination
// extents refer to. The blobs of the operations in |aops| should reference
// |blob_file|. |blob_file| are updated if needed.
static bool FragmentOperations(const PayloadVersion& version,
std::vector<AnnotatedOperation>* aops,
const std::string& target_part_path,
BlobFileWriter* blob_file);
// Takes a vector of AnnotatedOperations |aops| and sorts them by the first
// start block in their destination extents. Sets |aops| to a vector of the
// sorted operations.
static void SortOperationsByDestination(
std::vector<AnnotatedOperation>* aops);
// Takes an SOURCE_COPY install operation, |aop|, and adds one operation for
// each dst extent in |aop| to |ops|. The new operations added to |ops| will
// have only one dst extent. The src extents are split so the number of blocks
// in the src and dst extents are equal.
// E.g. we have a SOURCE_COPY operation:
// src extents: [(1, 3), (5, 1), (7, 1)], dst extents: [(2, 2), (6, 3)]
// Then we will get 2 new operations:
// 1. src extents: [(1, 2)], dst extents: [(2, 2)]
// 2. src extents: [(3, 1),(5, 1),(7, 1)], dst extents: [(6, 3)]
static bool SplitSourceCopy(const AnnotatedOperation& original_aop,
std::vector<AnnotatedOperation>* result_aops);
// Takes a REPLACE, REPLACE_BZ or REPLACE_XZ operation |aop|, and adds one
// operation for each dst extent in |aop| to |ops|. The new operations added
// to |ops| will have only one dst extent each, and may be of a different
// type depending on whether compression is advantageous.
static bool SplitAReplaceOp(const PayloadVersion& version,
const AnnotatedOperation& original_aop,
const std::string& target_part,
std::vector<AnnotatedOperation>* result_aops,
BlobFileWriter* blob_file);
// Takes a sorted (by first destination extent) vector of operations |aops|
// and merges SOURCE_COPY, REPLACE, REPLACE_BZ and REPLACE_XZ, operations in
// that vector.
// It will merge two operations if:
// - They are both REPLACE_*, or they are both SOURCE_COPY,
// - Their destination blocks are contiguous.
// - Their combined blocks do not exceed |chunk_blocks| blocks.
// Note that unlike other methods, you can't pass a negative number in
// |chunk_blocks|.
static bool MergeOperations(std::vector<AnnotatedOperation>* aops,
const PayloadVersion& version,
size_t chunk_blocks,
const std::string& target_part,
BlobFileWriter* blob_file);
// Takes a vector of AnnotatedOperations |aops|, adds source hash to all
// operations that have src_extents.
static bool AddSourceHash(std::vector<AnnotatedOperation>* aops,
const std::string& source_part_path);
// Adds the data payload for a REPLACE/REPLACE_BZ/REPLACE_XZ operation |aop|
// by reading its output extents from |target_part_path| and appending a
// corresponding data blob to |blob_file|. The blob will be compressed if this
// is smaller than the uncompressed form, and the operation type will be set
// accordingly. |*blob_file| will be updated as well. If the operation happens
// to have the right type and already points to a data blob, nothing is
// written. Caller should only set type and data blob if it's valid.
static bool AddDataAndSetType(AnnotatedOperation* aop,
const PayloadVersion& version,
const std::string& target_part_path,
BlobFileWriter* blob_file);
} // namespace chromeos_update_engine