Merge "libsnapshot: Stop reading ops once we reach a footer." (a1a5fdc6) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/cow_reader.cpp

+18 −6

Original line number	Diff line number	Diff line
		@@ -18,6 +18,7 @@
		#include <unistd.h>

		#include <limits>
		#include <optional>
		#include <vector>

		#include <android-base/file.h>
		@@ -117,8 +118,7 @@ bool CowReader::ParseOps() {
		PLOG(ERROR) << "lseek ops failed";
		return false;
		}
		uint64_t next_last_label = 0;
		bool has_next = false;
		std::optional<uint64_t> next_last_label;
		auto ops_buffer = std::make_shared<std::vector<CowOperation>>();
		if (has_footer_) ops_buffer->reserve(footer_.op.num_ops);
		uint64_t current_op_num = 0;
		@@ -146,11 +146,23 @@ bool CowReader::ParseOps() {
		has_last_label_ = true;
		last_label_ = current_op.source;
		} else {
		last_label_ = next_last_label;
		if (has_next) has_last_label_ = true;
		next_last_label = current_op.source;
		has_next = true;
		if (next_last_label) {
		last_label_ = next_last_label.value();
		has_last_label_ = true;
		}
		next_last_label = {current_op.source};
		}
		} else if (current_op.type == kCowFooterOp) {
		memcpy(&footer_.op, &current_op, sizeof(footer_.op));

		if (android::base::ReadFully(fd_, &footer_.data, sizeof(footer_.data))) {
		has_footer_ = true;
		if (next_last_label) {
		last_label_ = next_last_label.value();
		has_last_label_ = true;
		}
		}
		break;
		}
		}

+3 −0

Original line number	Diff line number	Diff line
		@@ -953,6 +953,9 @@ class SnapshotUpdateTest : public SnapshotTest {
		if (!WriteRandomData(writer.get(), &hashes_[name])) {
		return AssertionFailure() << "Unable to write random data to snapshot " << name;
		}
		if (!writer->Finalize()) {
		return AssertionFailure() << "Unable to finalize COW for " << name;
		}
		} else {
		std::string path;
		auto res = MapUpdateSnapshot(name, &path);