Do fcntl(...F_FULLFSYNC...) on mac instead of fsync

third_party/leveldatabase/env_chromium.cc

 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
 #include <errno.h>
 #include <stdio.h>
 
 #include <deque>
 
 #include "base/at_exit.h"
@@ skipping 50 matching lines @@
 }
 
 int fflush_wrapper(FILE *file) {
   return fflush(file);
 }
 
 #if !defined(OS_ANDROID)
 int fdatasync(int fildes) {
 #if defined(OS_WIN)
   return _commit(fildes);
+#elif defined(OS_MACOSX)
+  return HANDLE_EINTR(fcntl(fildes, F_FULLFSYNC, 0));

[jsbell, 2013/09/04 23:59:34]

Can fcntl() produce an EINTR error on MacOS with F_FULLFSYNC? The man page
appears to indicate it will only return that if F_SETLKW is returned.

It should be harmless to use this wrapper if that's the case, though.

[dgrogan, 2013/09/05 00:01:32]

Yeah, I added it just in case the man page was incomplete.

 #else
   return HANDLE_EINTR(fsync(fildes));
 #endif
 }
 #endif
 
 #else
 
 class TryToLockFILE {
   // This class should be deleted if it doesn't turn up anything useful after
@@ skipping 422 matching lines @@
 
 Status ChromiumWritableFile::Sync() {
   TRACE_EVENT0("leveldb", "ChromiumEnv::Sync");
   Status result;
   int error = 0;
 
   if (HANDLE_EINTR(fflush_wrapper(file_)))
     error = errno;
   // Sync even if fflush gave an error; perhaps the data actually got out,
   // even though something went wrong.
-  if (fdatasync(fileno(file_)) && !error)
+  if (fdatasync(fileno(file_)) == -1 && !error)

[jsbell, 2013/09/04 23:59:34]

Nice catch.

     error = errno;
   // Report the first error we found.
   if (error) {
     result = MakeIOError(filename_, strerror(error), kWritableFileSync, error);
     uma_logger_->RecordErrorAt(kWritableFileSync);
   }
   return result;
 }
 
 ChromiumEnv::ChromiumEnv()
@@ skipping 433 matching lines @@
 Env* IDBEnv() {
   return leveldb_env::idb_env.Pointer();
 }
 
 Env* Env::Default() {
   return leveldb_env::default_env.Pointer();
 }
 
 }  // namespace leveldb