tests/test-fwritable.c

   1 /* Test of fwritable() function.
   2    Copyright (C) 2007-2024 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>, 2007.  */
  18
  19 #include <config.h>
  20
  21 /* None of the files accessed by this test are large, so disable the
  22    fseek link warning if we are not using the gnulib fseek module.  */
  23 #define _GL_NO_LARGE_FILES
  24 #include "fwritable.h"
  25
  26 #include <stdio.h>
  27
  28 #include "macros.h"
  29
  30 #define TESTFILE "t-fwritable.tmp"
  31
  32 int
  33 main ()
  34 {
  35   FILE *fp;
  36
  37   /* Create a file with some contents.  */
  38   fp = fopen (TESTFILE, "w");
  39   if (fp == NULL)
  40     goto skip;
  41   ASSERT (fwritable (fp));
  42   if (fwrite ("foobarsh", 1, 8, fp) < 8)
  43     goto skip;
  44   ASSERT (fwritable (fp));
  45   if (fclose (fp))
  46     goto skip;
  47
  48   /* Open it in read-only mode.  */
  49   fp = fopen (TESTFILE, "r");
  50   if (fp == NULL)
  51     goto skip;
  52   ASSERT (!fwritable (fp));
  53   if (fgetc (fp) != 'f')
  54     goto skip;
  55   ASSERT (!fwritable (fp));
  56   if (fseek (fp, 2, SEEK_CUR))
  57     goto skip;
  58   ASSERT (!fwritable (fp));
  59   if (fgetc (fp) != 'b')
  60     goto skip;
  61   ASSERT (!fwritable (fp));
  62   fflush (fp);
  63   ASSERT (!fwritable (fp));
  64   if (fgetc (fp) != 'a')
  65     goto skip;
  66   ASSERT (!fwritable (fp));
  67   if (fseek (fp, 0, SEEK_END))
  68     goto skip;
  69   ASSERT (!fwritable (fp));
  70   if (fclose (fp))
  71     goto skip;
  72
  73   /* Open it in read-write mode.  */
  74   fp = fopen (TESTFILE, "r+");
  75   if (fp == NULL)
  76     goto skip;
  77   ASSERT (fwritable (fp));
  78   if (fgetc (fp) != 'f')
  79     goto skip;
  80   ASSERT (fwritable (fp));
  81   if (fseek (fp, 2, SEEK_CUR))
  82     goto skip;
  83   ASSERT (fwritable (fp));
  84   if (fgetc (fp) != 'b')
  85     goto skip;
  86   ASSERT (fwritable (fp));
  87   fflush (fp);
  88   ASSERT (fwritable (fp));
  89   if (fgetc (fp) != 'a')
  90     goto skip;
  91   ASSERT (fwritable (fp));
  92   if (fputc ('z', fp) != 'z')
  93     goto skip;
  94   ASSERT (fwritable (fp));
  95   if (fseek (fp, 0, SEEK_END))
  96     goto skip;
  97   ASSERT (fwritable (fp));
  98   if (fclose (fp))
  99     goto skip;
 100
 101   /* Open it in append mode.  */
 102   fp = fopen (TESTFILE, "a");
 103   if (fp == NULL)
 104     goto skip;
 105   ASSERT (fwritable (fp));
 106   if (fwrite ("bla", 1, 3, fp) < 3)
 107     goto skip;
 108   ASSERT (fwritable (fp));
 109   if (fclose (fp))
 110     goto skip;
 111
 112   return test_exit_status;
 113
 114  skip:
 115   if (test_exit_status != EXIT_SUCCESS)
 116     return test_exit_status;
 117   fprintf (stderr, "Skipping test: file operations failed.\n");
 118   return 77;
 119 }