open-safer.c 1.4 KB

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  1. /* Invoke open, but avoid some glitches.
  2. Copyright (C) 2005, 2006 Free Software Foundation, Inc.
  3. This program is free software: you can redistribute it and/or modify
  4. it under the terms of the GNU General Public License as published by
  5. the Free Software Foundation; either version 3 of the License, or
  6. (at your option) any later version.
  7. This program is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  10. GNU General Public License for more details.
  11. You should have received a copy of the GNU General Public License
  12. along with this program. If not, see <http://www.gnu.org/licenses/>. */
  13. /* Written by Paul Eggert. */
  14. #include <config.h>
  15. #include "fcntl-safer.h"
  16. #include <fcntl.h>
  17. #include <stdarg.h>
  18. #include "unistd-safer.h"
  19. int
  20. open_safer (char const *file, int flags, ...)
  21. {
  22. mode_t mode = 0;
  23. if (flags & O_CREAT)
  24. {
  25. va_list ap;
  26. va_start (ap, flags);
  27. /* Assume mode_t promotes to int if and only if it is smaller.
  28. This assumption isn't guaranteed by the C standard, but we
  29. don't know of any real-world counterexamples. */
  30. mode = (sizeof (mode_t) < sizeof (int)
  31. ? va_arg (ap, int)
  32. : va_arg (ap, mode_t));
  33. va_end (ap);
  34. }
  35. return fd_safer (open (file, flags, mode));
  36. }