Merge "Fsync on directory after rename() call" (b3c89fa6) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/utility.cpp

+21 −2

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@
		#include <errno.h>
		#include <time.h>

		#include <filesystem>
		#include <iomanip>
		#include <sstream>

		@@ -152,6 +153,24 @@ AutoUnmountDevice::~AutoUnmountDevice() {
		}
		}

		bool FsyncDirectory(const char* dirname) {
		android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(dirname, O_RDONLY \| O_CLOEXEC)));
		if (fd == -1) {
		PLOG(ERROR) << "Failed to open " << dirname;
		return false;
		}
		if (fsync(fd) == -1) {
		if (errno == EROFS \|\| errno == EINVAL) {
		PLOG(WARNING) << "Skip fsync " << dirname
		<< " on a file system does not support synchronization";
		} else {
		PLOG(ERROR) << "Failed to fsync " << dirname;
		return false;
		}
		}
		return true;
		}

		bool WriteStringToFileAtomic(const std::string& content, const std::string& path) {
		const std::string tmp_path = path + ".tmp";
		{
		@@ -175,11 +194,11 @@ bool WriteStringToFileAtomic(const std::string& content, const std::string& path
		PLOG(ERROR) << "rename failed from " << tmp_path << " to " << path;
		return false;
		}
		return true;
		return FsyncDirectory(std::filesystem::path(path).parent_path().c_str());
		}

		std::ostream& operator<<(std::ostream& os, const Now&) {
		struct tm now;
		struct tm now {};
		time_t t = time(nullptr);
		localtime_r(&t, &now);
		return os << std::put_time(&now, "%Y%m%d-%H%M%S");

+1 −0

Original line number	Diff line number	Diff line
		@@ -117,6 +117,7 @@ Return InitializeKernelCow(const std::string& device);
		// Note that rename() is an atomic operation. This function may not work properly if there
		// is an open fd to \|path\|, because that fd has an old view of the file.
		bool WriteStringToFileAtomic(const std::string& content, const std::string& path);
		bool FsyncDirectory(const char* dirname);

		// Writes current time to a given stream.
		struct Now {};