VFS: Call msync when syncing mapped data

CHANGES

@@ -19,6 +19,7 @@ Misc:
  - GBA Video: Clean up unused timers
  - Test: Add a basic test suite
  - GBA Video: Allow multiple handles into the same tile cache
+ - VFS: Call msync when syncing mapped data
 
 0.5.1: (2016-10-05)
 Bugfixes:

src/util/vfs/vfs-fd.c

@@ -167,6 +167,9 @@ static bool _vfdSync(struct VFile* vf, const void* buffer, size_t size) {
 	struct VFileFD* vfd = (struct VFileFD*) vf;
 #ifndef _WIN32
 	futimes(vfd->fd, NULL);
+	if (buffer && size) {
+		return msync(buffer, size, MS_SYNC) == 0;
+	}
 	return fsync(vfd->fd) == 0;
 #else
 	HANDLE h = (HANDLE) _get_osfhandle(vfd->fd);