Add a binary to generate .map files from filesystem image
This allows us to re-use existing .img files when building target_files.
Target_files includes both .img files and .map file for each partition.
If we already have the .img file ready, we can derive file block
information from the filesystem image, instead of re-generating the
image with block map option.
Test: th
Bug: 281960439
Change-Id: I61cfe32195e26ed68bfc1b7dc138fd68a583cbc1
diff --git a/aosp/map_file_generator.cc b/aosp/map_file_generator.cc
new file mode 100644
index 0000000..1943a66
--- /dev/null
+++ b/aosp/map_file_generator.cc
@@ -0,0 +1,89 @@
+//
+// 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 "android-base/stringprintf.h"
+#include "android-base/unique_fd.h"
+#include "common/utils.h"
+#include "update_engine/payload_generator/ext2_filesystem.h"
+#include "update_engine/payload_generator/erofs_filesystem.h"
+#include "update_engine/payload_generator/filesystem_interface.h"
+
+namespace chromeos_update_engine {
+
+int WriteBlockMap(const char* img,
+ const FilesystemInterface* fs,
+ const char* output_file) {
+ std::vector<FilesystemInterface::File> files;
+ if (!fs->GetFiles(&files)) {
+ LOG(ERROR) << "Failed to parse file info in " << img;
+ return -2;
+ }
+ android::base::unique_fd fd(
+ open(output_file, O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0644));
+ if (fd < 0) {
+ PLOG(ERROR) << "Failed to open " << output_file;
+ return -errno;
+ }
+ for (const auto& file : files) {
+ if (file.extents.empty()) {
+ continue;
+ }
+ std::string output_line;
+ output_line.append(file.name);
+ for (const auto& extent : file.extents) {
+ if (extent.num_blocks() <= 0) {
+ continue;
+ }
+ output_line.append(" ");
+ if (extent.num_blocks() == 1) {
+ output_line.append(std::to_string(extent.start_block()));
+ continue;
+ }
+ const auto extent_str = android::base::StringPrintf(
+ "%lu-%lu",
+ extent.start_block(),
+ extent.start_block() + extent.num_blocks() - 1);
+ output_line.append(extent_str);
+ }
+ output_line.append("\n");
+ if (!utils::WriteAll(fd.get(), output_line.data(), output_line.size())) {
+ PLOG(ERROR) << "Failed to write to " << output_file;
+ return -errno;
+ }
+ }
+ return 0;
+}
+
+int Main(int argc, const char* argv[]) {
+ const char* img = argv[1];
+ const char* output_file = argv[2];
+ std::unique_ptr<FilesystemInterface> fs;
+ fs = ErofsFilesystem::CreateFromFile(img);
+ if (fs != nullptr) {
+ return WriteBlockMap(img, fs.get(), output_file);
+ }
+ fs = Ext2Filesystem::CreateFromFile(img);
+ if (fs != nullptr) {
+ return WriteBlockMap(img, fs.get(), output_file);
+ }
+ LOG(ERROR) << "Failed to parse " << img;
+ return -1;
+}
+} // namespace chromeos_update_engine
+
+int main(int argc, const char* argv[]) {
+ return chromeos_update_engine::Main(argc, argv);
+}
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