posix: replace nonstandard futimes call with futimens

base/platform_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/platform_file.h"
 
 #include <fcntl.h>
 #include <errno.h>
 #include <sys/stat.h>
 #include <unistd.h>
@@ skipping 280 matching lines @@
   base::ThreadRestrictions::AssertIOAllowed();
   return !HANDLE_EINTR(fsync(file));
 }
 
 bool TouchPlatformFile(PlatformFile file, const base::Time& last_access_time,
                        const base::Time& last_modified_time) {
   base::ThreadRestrictions::AssertIOAllowed();
   if (file < 0)
     return false;
 
-  timeval times[2];
-  times[0] = last_access_time.ToTimeVal();
-  times[1] = last_modified_time.ToTimeVal();
-  return !futimes(file, times);
+  timeval tv[2];
+  tv[0] = last_access_time.ToTimeVal();

[darin (slow to review), 2013/04/10 17:51:05]

nit: The code might be more readable with named variables here instead of array
slots.

timeval last_access_time_val = last_access_time.ToTimeVal();
timeval last_modified_time_val = ...

timespec ts[2];
ts[0].tv_sec = last_access_time_val.tv_sec;
ts[0].tv_nsec = last_access_time_val.tv_usec * 1000;
...

Another approach would be to create a static helper function for converting
timeval to timespec.  Or, better yet, since ToTimeVal() is actually only used by
this callsite, perhaps Time::ToTimeVal should be changed to ToTimeSpec??

(The other callsites are just unit tests that could be fixed up to use
ToTimeSpec instead of ToTimeVal.)

[Mostyn Bramley-Moore, 2013/04/10 20:59:07]

Done.

+  tv[1] = last_modified_time.ToTimeVal();
+
+  timespec ts[2];
+  ts[0].tv_sec  = tv[0].tv_sec;
+  ts[0].tv_nsec = tv[0].tv_usec * 1000;
+  ts[1].tv_sec  = tv[1].tv_sec;
+  ts[1].tv_nsec = tv[1].tv_usec * 1000;
+
+  return !futimens(file, ts);
 }
 
 bool GetPlatformFileInfo(PlatformFile file, PlatformFileInfo* info) {
   if (!info)
     return false;
 
   stat_wrapper_t file_info;
   if (CallFstat(file, &file_info))
     return false;
 
   info->is_directory = S_ISDIR(file_info.st_mode);
   info->is_symbolic_link = S_ISLNK(file_info.st_mode);
   info->size = file_info.st_size;
   info->last_modified = base::Time::FromTimeT(file_info.st_mtime);
   info->last_accessed = base::Time::FromTimeT(file_info.st_atime);
   info->creation_time = base::Time::FromTimeT(file_info.st_ctime);
   return true;
 }
 
 }  // namespace base