New upstream version 1.8

[debian/gzip] / lib / openat-safer.c

diff --git a/lib/openat-safer.c b/lib/openat-safer.c
new file mode 100644 (file)
index 0000000..5a957d0
--- /dev/null
+++ b/lib/openat-safer.c
@@ -0,0 +1,46 @@
+/* Invoke openat, but avoid some glitches.
+
+   Copyright (C) 2005-2006, 2008-2016 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert for open, ported by Eric Blake for openat.  */
+
+#include <config.h>
+
+#include "fcntl-safer.h"
+
+#include <fcntl.h>
+#include <stdarg.h>
+#include "unistd-safer.h"
+
+int
+openat_safer (int fd, char const *file, int flags, ...)
+{
+  mode_t mode = 0;
+
+  if (flags & O_CREAT)
+    {
+      va_list ap;
+      va_start (ap, flags);
+
+      /* We have to use PROMOTED_MODE_T instead of mode_t, otherwise GCC 4
+         creates crashing code when 'mode_t' is smaller than 'int'.  */
+      mode = va_arg (ap, PROMOTED_MODE_T);
+
+      va_end (ap);
+    }
+
+  return fd_safer (openat (fd, file, flags, mode));
+}