libio/tst-fdopen-seek-failure.c

   1 /* Test for fdopen memory leak without SEEK_END support (bug 31840).
   2    Copyright (C) 2024-2025 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <mcheck.h>
  23 #include <stddef.h>
  24 #include <stdio.h>
  25 #include <support/check.h>
  26 #include <support/xunistd.h>
  27 #include <unistd.h>
  28
  29 static int
  30 do_test (void)
  31 {
  32   mtrace ();
  33
  34   /* This file is special because it is seekable, but only
  35      with SEEK_SET, not SEEK_END.  */
  36   int fd = open ("/proc/self/mem", O_RDWR);
  37   if (fd < 0)
  38     FAIL_UNSUPPORTED ("/proc/self/mem not found: %m");
  39   FILE *fp = fdopen (fd, "a");
  40   /* The fdopen call should have failed because it tried to use
  41      SEEK_END.  */
  42   TEST_VERIFY (fp == NULL);
  43   TEST_COMPARE (errno, EINVAL);
  44   xclose (fd);
  45   return 0;
  46 }
  47
  48 #include <support/test-driver.c>