Add utime implementation to libnacl

src/untrusted/nacl/utime.c

+/*
+ * Copyright 2015 The Native Client 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 <sys/types.h>
+#include <utime.h>
+#include <sys/time.h>
+#include <errno.h>

[Mark Seaborn, 2015/04/07 19:08:43]

Sort #includes

[Sam Clegg, 2015/04/10 21:18:55]

Done.

+#include <stdio.h>

[Mark Seaborn, 2015/04/07 19:08:43]

Not needed

[Sam Clegg, 2015/04/10 21:18:56]

Done.

+
+#include "native_client/src/untrusted/nacl/nacl_irt.h"

[Mark Seaborn, 2015/04/07 19:08:43]

Not needed with the change below...

[Sam Clegg, 2015/04/10 21:18:55]

Done.

+
+/*
+ * Implementation of utime based on the utimes IRT function.  utime works
+ * just like utimes but only support timestamps with a granularity of one
+ * second (support time_t).  This means we we can use utimes to impelement

[Mark Seaborn, 2015/04/07 19:08:43]

What do you mean by "support time_t"?  Can you remove that parenthetical comment
or clean it up?

Also: "implement"

[Sam Clegg, 2015/04/10 21:18:56]

Done.

+ * utime by simply setting tv_sec fields to zero.
+ */
+int utime(const char *filename, const struct utimbuf *buf) {
+  if (!__libnacl_irt_init_fn(&__libnacl_irt_dev_filename.utimes,
+                             __libnacl_irt_dev_filename_init)) {
+    return -1;
+  }
+
+  struct timeval times[2];
+  struct timeval* tv = NULL;

[Mark Seaborn, 2015/04/07 19:08:43]

Use " *" spacing

[Sam Clegg, 2015/04/10 21:18:55]

Done.

+  if (buf != NULL) {
+    times[0].tv_sec = buf->actime;
+    times[1].tv_sec = buf->modtime;
+    times[0].tv_usec = 0;
+    times[1].tv_usec = 0;
+    tv = times;
+  }
+
+  int error = __libnacl_irt_dev_filename.utimes(filename, tv);

[Mark Seaborn, 2015/04/07 19:08:43]

Just call utimes() instead of getting the IRT interface.  Then you don't need
the sys_private.c change.

[Sam Clegg, 2015/04/10 21:18:55]

Done.

+  if (error) {
+    errno = error;
+    return -1;
+  }
+
+  return 0;
+}