Let ImportantFileWriter Use fdatasync

base/files/file_posix.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/files/file.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <unistd.h>
@@ skipping 35 matching lines @@
 // wrap them in order to minimize the number of #ifdef's in this file.
 #if !defined(OS_NACL)
 static bool IsOpenAppend(PlatformFile file) {
   return (fcntl(file, F_GETFL) & O_APPEND) != 0;
 }
 
 static int CallFtruncate(PlatformFile file, int64 length) {
   return HANDLE_EINTR(ftruncate(file, length));
 }
 
-static int CallFsync(PlatformFile file) {
-  return HANDLE_EINTR(fsync(file));
-}
-
 static int CallFutimes(PlatformFile file, const struct timeval times[2]) {
 #ifdef __USE_XOPEN2K8
   // futimens should be available, but futimes might not be
   // http://pubs.opengroup.org/onlinepubs/9699919799/
 
   timespec ts_times[2];
   ts_times[0].tv_sec  = times[0].tv_sec;
   ts_times[0].tv_nsec = times[0].tv_usec * 1000;
   ts_times[1].tv_sec  = times[1].tv_sec;
   ts_times[1].tv_nsec = times[1].tv_usec * 1000;
@@ skipping 21 matching lines @@
   // standard and always appends if the file is opened with O_APPEND, just
   // return false here.
   return false;
 }
 
 static int CallFtruncate(PlatformFile file, int64 length) {
   NOTIMPLEMENTED();  // NaCl doesn't implement ftruncate.
   return 0;
 }
 
-static int CallFsync(PlatformFile file) {
-  NOTIMPLEMENTED();  // NaCl doesn't implement fsync.
-  return 0;
-}
-
 static int CallFutimes(PlatformFile file, const struct timeval times[2]) {
   NOTIMPLEMENTED();  // NaCl doesn't implement futimes.
   return 0;
 }
 
 static File::Error CallFctnlFlock(PlatformFile file, bool do_lock) {
   NOTIMPLEMENTED();  // NaCl doesn't implement flock struct.
   return File::FILE_ERROR_INVALID_OPERATION;
 }
 #endif  // defined(OS_NACL)
@@ skipping 307 matching lines @@
 
 bool File::SetLength(int64 length) {
   base::ThreadRestrictions::AssertIOAllowed();
   DCHECK(IsValid());
   return !CallFtruncate(file_.get(), length);
 }
 
 bool File::Flush() {
   base::ThreadRestrictions::AssertIOAllowed();
   DCHECK(IsValid());
-  return !CallFsync(file_.get());
+#if defined(OS_NACL)
+  NOTIMPLEMENTED();  // NaCl doesn't implement fsync.
+  return true;
+#elif defined(OS_LINUX) || defined(OS_ANDROID)
+  return !HANDLE_EINTR(fdatasync(file_.get()));
+#else
+  return !HANDLE_EINTR(fsync(file_.get()));
+#endif
 }
 
 bool File::SetTimes(Time last_access_time, Time last_modified_time) {
   base::ThreadRestrictions::AssertIOAllowed();
   DCHECK(IsValid());
 
   timeval times[2];
   times[0] = last_access_time.ToTimeVal();
   times[1] = last_modified_time.ToTimeVal();
 
@@ skipping 113 matching lines @@
 }
 
 void File::SetPlatformFile(PlatformFile file) {
   CHECK(!file_.is_valid());
   file_.reset(file);
   if (file_.is_valid())
     ProtectFileDescriptor(GetPlatformFile());
 }
 
 }  // namespace base