Vold: Add fsync in writeStringToFile()

Test: Build, test with ag/3180275
Bug: 68901441
Change-Id: Ieca9e5227025e00184a67508d5e8fbbddd12f21e
This commit is contained in:
Wei Wang 2017-11-07 09:44:16 -08:00
parent d4af166db8
commit 701d05d32c

View file

@ -35,6 +35,7 @@
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/unique_fd.h>
#include <cutils/properties.h>
@ -153,10 +154,29 @@ static bool readFileToString(const std::string& filename, std::string* result) {
}
static bool writeStringToFile(const std::string& payload, const std::string& filename) {
if (!android::base::WriteStringToFile(payload, filename)) {
PLOG(ERROR) << "Failed to write to " << filename;
android::base::unique_fd fd(TEMP_FAILURE_RETRY(
open(filename.c_str(), O_WRONLY | O_CREAT | O_NOFOLLOW | O_TRUNC | O_CLOEXEC, 0666)));
if (fd == -1) {
PLOG(ERROR) << "Failed to open " << filename;
return false;
}
if (!android::base::WriteStringToFd(payload, fd)) {
PLOG(ERROR) << "Failed to write to " << filename;
unlink(filename.c_str());
return false;
}
// fsync as close won't guarantee flush data
// see close(2), fsync(2) and b/68901441
if (fsync(fd) == -1) {
if (errno == EROFS || errno == EINVAL) {
PLOG(WARNING) << "Skip fsync " << filename
<< " on a file system does not support synchronization";
} else {
PLOG(ERROR) << "Failed to fsync " << filename;
unlink(filename.c_str());
return false;
}
}
return true;
}