Merge "Add v3 writer" into main

fs_mgr/libsnapshot/Android.bp

@@ -201,6 +201,7 @@ cc_library_static {
         "libsnapshot_cow/snapshot_reader.cpp",
         "libsnapshot_cow/writer_base.cpp",
         "libsnapshot_cow/writer_v2.cpp",
+        "libsnapshot_cow/writer_v3.cpp",
     ],
     export_include_dirs: ["include"],
     host_supported: true,
@@ -392,6 +393,7 @@ cc_test {
     srcs: [
         "libsnapshot_cow/snapshot_reader_test.cpp",
         "libsnapshot_cow/test_v2.cpp",
+        "libsnapshot_cow/test_v3.cpp",
     ],
     cflags: [
         "-D_FILE_OFFSET_BITS=64",

fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp

@@ -0,0 +1,53 @@
+// Copyright (C) 2023 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 <sys/stat.h>
+
+#include <cstdio>
+#include <iostream>
+#include <memory>
+#include <string_view>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <gtest/gtest.h>
+#include <libsnapshot/cow_reader.h>
+#include <libsnapshot/cow_writer.h>
+#include "cow_decompress.h"
+#include "libsnapshot/cow_format.h"
+#include "writer_v3.h"
+using android::base::unique_fd;
+using testing::AssertionFailure;
+using testing::AssertionResult;
+using testing::AssertionSuccess;
+
+namespace android {
+namespace snapshot {
+
+class CowOperationV3Test : public ::testing::Test {
+  protected:
+    virtual void SetUp() override {
+        cow_ = std::make_unique<TemporaryFile>();
+        ASSERT_GE(cow_->fd, 0) << strerror(errno);
+    }
+
+    virtual void TearDown() override { cow_ = nullptr; }
+
+    unique_fd GetCowFd() { return unique_fd{dup(cow_->fd)}; }
+
+    std::unique_ptr<TemporaryFile> cow_;
+};
+
+}  // namespace snapshot
+}  // namespace android

fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp

@@ -0,0 +1,117 @@
+//
+// Copyright (C) 2020 The Android Open Source_info 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 "writer_v3.h"
+
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/parseint.h>
+#include <android-base/properties.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+#include <brotli/encode.h>
+#include <libsnapshot/cow_format.h>
+#include <libsnapshot/cow_reader.h>
+#include <libsnapshot/cow_writer.h>
+#include <lz4.h>
+#include <zlib.h>
+
+#include <fcntl.h>
+#include <linux/fs.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+// The info messages here are spammy, but as useful for update_engine. Disable
+// them when running on the host.
+#ifdef __ANDROID__
+#define LOG_INFO LOG(INFO)
+#else
+#define LOG_INFO LOG(VERBOSE)
+#endif
+
+namespace android {
+namespace snapshot {
+
+static_assert(sizeof(off_t) == sizeof(uint64_t));
+
+using android::base::unique_fd;
+
+CowWriterV3::CowWriterV3(const CowOptions& options, unique_fd&& fd)
+    : CowWriterBase(options, std::move(fd)) {}
+
+CowWriterV3::~CowWriterV3() {}
+
+bool CowWriterV3::Initialize(std::optional<uint64_t> label) {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+    if (label) return false;
+    return false;
+}
+
+bool CowWriterV3::EmitCopy(uint64_t new_block, uint64_t old_block, uint64_t num_blocks) {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+    if (new_block || old_block || num_blocks) return false;
+    return false;
+}
+
+bool CowWriterV3::EmitRawBlocks(uint64_t new_block_start, const void* data, size_t size) {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+
+    if (new_block_start || data || size) return false;
+    return false;
+}
+
+bool CowWriterV3::EmitXorBlocks(uint32_t new_block_start, const void* data, size_t size,
+                                uint32_t old_block, uint16_t offset) {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+    if (new_block_start || old_block || offset || data || size) return false;
+    return false;
+}
+
+bool CowWriterV3::EmitZeroBlocks(uint64_t new_block_start, uint64_t num_blocks) {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+    if (new_block_start && num_blocks) return false;
+    return false;
+}
+
+bool CowWriterV3::EmitLabel(uint64_t label) {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+    if (label) return false;
+    return false;
+}
+
+bool CowWriterV3::EmitSequenceData(size_t num_ops, const uint32_t* data) {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+    if (num_ops && data) return false;
+    return false;
+}
+
+bool CowWriterV3::Finalize() {
+    LOG(ERROR) << __LINE__ << " " << __FILE__ << " <- function here should never be called";
+    return false;
+}
+
+uint64_t CowWriterV3::GetCowSize() {
+    LOG(ERROR) << __LINE__ << " " << __FILE__
+               << " <- Get Cow Size function here should never be called";
+    return 0;
+}
+
+}  // namespace snapshot
+}  // namespace android

fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.h

@@ -0,0 +1,43 @@
+// Copyright (C) 2023 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.
+
+#pragma once
+
+#include <future>
+#include "writer_base.h"
+
+namespace android {
+namespace snapshot {
+
+class CowWriterV3 : public CowWriterBase {
+  public:
+    explicit CowWriterV3(const CowOptions& options, android::base::unique_fd&& fd);
+    ~CowWriterV3() override;
+
+    bool Initialize(std::optional<uint64_t> label = {}) override;
+    bool Finalize() override;
+    uint64_t GetCowSize() override;
+
+  protected:
+    virtual bool EmitCopy(uint64_t new_block, uint64_t old_block, uint64_t num_blocks = 1) override;
+    virtual bool EmitRawBlocks(uint64_t new_block_start, const void* data, size_t size) override;
+    virtual bool EmitXorBlocks(uint32_t new_block_start, const void* data, size_t size,
+                               uint32_t old_block, uint16_t offset) override;
+    virtual bool EmitZeroBlocks(uint64_t new_block_start, uint64_t num_blocks) override;
+    virtual bool EmitLabel(uint64_t label) override;
+    virtual bool EmitSequenceData(size_t num_ops, const uint32_t* data) override;
+};
+
+}  // namespace snapshot
+}  // namespace android