tests/test-freadptr.c

   1 /* Test of freadptr() function.
   2    Copyright (C) 2007-2025 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2008.  */
  18
  19 #include <config.h>
  20
  21 #include "freadptr.h"
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26
  27 #include "macros.h"
  28
  29 int
  30 main (int argc, char **argv)
  31 {
  32   int nbytes = atoi (argv[1]);
  33   {
  34     void *buf = malloc (nbytes);
  35     ASSERT (fread (buf, 1, nbytes, stdin) == nbytes);
  36     free (buf);
  37   }
  38
  39   if (lseek (0, 0, SEEK_CUR) == nbytes)
  40     {
  41       /* An unbuffered stdio, such as BeOS or on uClibc compiled without
  42          __STDIO_BUFFERS.  Or stdin is a pipe.  */
  43       size_t size;
  44       ASSERT (freadptr (stdin, &size) == NULL);
  45     }
  46   else
  47     {
  48       /* Normal buffered stdio.  */
  49       const char stdin_contents[] =
  50         "#!/bin/sh\n\n${CHECKER} ./test-freadptr${EXEEXT} 5 < \"$srcdir/test-freadptr.sh\" || exit 1\ncat \"$srcdir/test-freadptr.sh\" | ${CHECKER} ./test-freadptr${EXEEXT} 5 || exit 1\nexit 0\n";
  51       const char *expected = stdin_contents + nbytes;
  52       size_t available1;
  53       size_t available2;
  54       size_t available3;
  55
  56       /* Test normal behaviour.  */
  57       {
  58         const char *ptr = freadptr (stdin, &available1);
  59
  60         ASSERT (ptr != NULL);
  61         ASSERT (available1 != 0);
  62         ASSERT (available1 <= strlen (expected));
  63         ASSERT (memcmp (ptr, expected, available1) == 0);
  64       }
  65
  66       /* Test behaviour after normal ungetc.  */
  67       ungetc (fgetc (stdin), stdin);
  68       {
  69         const char *ptr = freadptr (stdin, &available2);
  70
  71         if (ptr != NULL)
  72           {
  73             ASSERT (available2 == available1);
  74             ASSERT (memcmp (ptr, expected, available2) == 0);
  75           }
  76       }
  77
  78       /* Test behaviour after arbitrary ungetc.  */
  79       fgetc (stdin);
  80       ungetc ('@', stdin);
  81       {
  82         const char *ptr = freadptr (stdin, &available3);
  83
  84         if (ptr != NULL)
  85           {
  86             ASSERT (available3 == 1 || available3 == available1);
  87             ASSERT (ptr[0] == '@');
  88             if (available3 > 1)
  89               {
  90                 ASSERT (memcmp (ptr + 1, expected + 1, available3 - 1) == 0);
  91               }
  92           }
  93       }
  94     }
  95
  96   /* Free memory allocated during ungetc().  */
  97   fclose (stdin);
  98
  99   return test_exit_status;
 100 }