libio/tst-bz22415.c

   1 /* Check static buffer handling with setvbuf (BZ #22415)
   2
   3    Copyright (C) 2017-2022 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <https://www.gnu.org/licenses/>.  */
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <wchar.h>
  23 #include <mcheck.h>
  24
  25 #include <support/check.h>
  26 #include <support/temp_file.h>
  27
  28 static int
  29 do_test (void)
  30 {
  31   mtrace ();
  32
  33   char *temp_file;
  34   TEST_VERIFY_EXIT (create_temp_file ("tst-bz22145.", &temp_file));
  35
  36   char buf[BUFSIZ];
  37
  38   {
  39     /* Check if backup buffer is correctly freed and changing back
  40        to normal buffer does not trigger an invalid free in case of
  41        static buffer set by setvbuf.  */
  42
  43     FILE *f = fopen (temp_file, "w+b");
  44     TEST_VERIFY_EXIT (f != NULL);
  45
  46     TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
  47     TEST_VERIFY_EXIT (ungetc ('x', f) == 'x');
  48     TEST_VERIFY_EXIT (fseek (f, 0L, SEEK_SET) == 0);
  49     TEST_VERIFY_EXIT (fputc ('y', f) ==  'y');
  50
  51     TEST_VERIFY_EXIT (fclose (f) == 0);
  52   }
  53
  54   {
  55     /* Check if backup buffer is correctly freed and changing back
  56        to normal buffer does not trigger an invalid free in case of
  57        static buffer set by setvbuf.  */
  58
  59     FILE *f = fopen (temp_file, "w+b");
  60     TEST_VERIFY_EXIT (f != NULL);
  61
  62     TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
  63     TEST_VERIFY_EXIT (ungetc ('x', f) == 'x');
  64     TEST_VERIFY_EXIT (fputc ('y', f) ==  'y');
  65
  66     TEST_VERIFY_EXIT (fclose (f) == 0);
  67   }
  68
  69   {
  70     FILE *f = fopen (temp_file, "w+b");
  71     TEST_VERIFY_EXIT (f != NULL);
  72
  73     TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
  74     TEST_VERIFY_EXIT (ungetwc (L'x', f) == L'x');
  75     TEST_VERIFY_EXIT (fseek (f, 0L, SEEK_SET) == 0);
  76     TEST_VERIFY_EXIT (fputwc (L'y', f) ==  L'y');
  77
  78     TEST_VERIFY_EXIT (fclose (f) == 0);
  79   }
  80
  81   {
  82     FILE *f = fopen (temp_file, "w+b");
  83     TEST_VERIFY_EXIT (f != NULL);
  84
  85     TEST_VERIFY_EXIT (setvbuf (f, buf, _IOFBF, BUFSIZ) == 0);
  86     TEST_VERIFY_EXIT (ungetwc (L'x', f) == L'x');
  87     TEST_VERIFY_EXIT (fputwc (L'y', f) ==  L'y');
  88
  89     TEST_VERIFY_EXIT (fclose (f) == 0);
  90   }
  91
  92   free (temp_file);
  93
  94   return 0;
  95 }
  96
  97 #include <support/test-driver.c>