1  /* Test that _IO_wfile_sync does not crash (bug 20568).
       2     Copyright (C) 2019-2023 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  #include <fcntl.h>
      20  #include <locale.h>
      21  #include <stdio.h>
      22  #include <stdlib.h>
      23  #include <string.h>
      24  #include <wchar.h>
      25  #include <support/check.h>
      26  #include <support/xstdio.h>
      27  #include <support/xunistd.h>
      28  #include <support/temp_file.h>
      29  
      30  static const char test_data[] = "This is a test of _IO_wfile_sync.";
      31  
      32  static int
      33  do_test (void)
      34  {
      35    static char *infile;
      36    int infd;
      37    FILE *infp;
      38  
      39    infd = create_temp_file ("tst-wfile-sync-in-", &infile);
      40    xwrite (infd, test_data, strlen (test_data));
      41    xclose (infd);
      42  
      43    infd = xopen (infile, O_RDONLY, 0);
      44    infp = fdopen (infd, "r");
      45  
      46    TEST_VERIFY_EXIT (setlocale (LC_ALL, "de_DE.UTF-8") != NULL);
      47    /* Fill the stdio buffer and advance the read pointer.  */
      48    TEST_VERIFY_EXIT (fgetwc (infp) != WEOF);
      49    /* This calls _IO_wfile_sync, it should not crash.  */
      50    TEST_VERIFY_EXIT (setvbuf (infp, NULL, _IONBF, 0) == 0);
      51    /* Verify that the external file offset has been synchronized.  */
      52    TEST_COMPARE (xlseek (infd, 0, SEEK_CUR), 1);
      53  
      54    fclose (infp);
      55    free (infile);
      56  
      57    return 0;
      58  }
      59  
      60  #include <support/test-driver.c>