stdio-common/test_rdwr.c

   1 /* Copyright (C) 1991, 1992, 1996 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3
   4 The GNU C Library is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 License, or (at your option) any later version.
   8
   9 The GNU C Library 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 GNU
  12 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <errno.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23
  24
  25 int
  26 main (int argc, char **argv)
  27 {
  28   static const char hello[] = "Hello, world.\n";
  29   static const char replace[] = "Hewwo, world.\n";
  30   static const size_t replace_from = 2, replace_to = 4;
  31   char filename[FILENAME_MAX];
  32   char *name = strrchr(*argv, '/');
  33   char buf[BUFSIZ];
  34   FILE *f;
  35   int lose = 0;
  36
  37   if (name != NULL)
  38     ++name;
  39   else
  40     name = *argv;
  41
  42   (void) sprintf(filename, "/tmp/%s.test", name);
  43
  44   f = fopen(filename, "w+");
  45   if (f == NULL)
  46     {
  47       perror(filename);
  48       exit(1);
  49     }
  50
  51   (void) fputs(hello, f);
  52   rewind(f);
  53   (void) fgets(buf, sizeof(buf), f);
  54   rewind(f);
  55   (void) fputs(buf, f);
  56   rewind(f);
  57   {
  58     register size_t i;
  59     for (i = 0; i < replace_from; ++i)
  60       {
  61         int c = getc(f);
  62         if (c == EOF)
  63           {
  64             printf("EOF at %u.\n", i);
  65             lose = 1;
  66             break;
  67           }
  68         else if (c != hello[i])
  69           {
  70             printf("Got '%c' instead of '%c' at %u.\n",
  71                    (unsigned char) c, hello[i], i);
  72             lose = 1;
  73             break;
  74           }
  75       }
  76   }
  77
  78   {
  79     long int where = ftell(f);
  80     if (where == (long int) replace_from)
  81       {
  82         register size_t i;
  83         for (i = replace_from; i < replace_to; ++i)
  84           if (putc(replace[i], f) == EOF)
  85             {
  86               printf("putc('%c') got %s at %u.\n",
  87                      replace[i], strerror(errno), i);
  88               lose = 1;
  89               break;
  90             }
  91       }
  92     else if (where == -1L)
  93       {
  94         printf("ftell got %s (should be at %u).\n",
  95                strerror(errno), replace_from);
  96         lose = 1;
  97       }
  98     else
  99       {
 100         printf("ftell returns %lu; should be %u.\n", where, replace_from);
 101         lose = 1;
 102       }
 103   }
 104
 105   if (!lose)
 106     {
 107       rewind(f);
 108       if (fgets(buf, sizeof(buf), f) == NULL)
 109         {
 110           printf("fgets got %s.\n", strerror(errno));
 111           lose = 1;
 112         }
 113       else if (strcmp(buf, replace))
 114         {
 115           printf("Read \"%s\" instead of \"%s\".\n", buf, replace);
 116           lose = 1;
 117         }
 118     }
 119
 120   if (lose)
 121     printf("Test FAILED!  Losing file is \"%s\".\n", filename);
 122   else
 123     {
 124       (void) remove(filename);
 125       puts("Test succeeded.");
 126     }
 127
 128   exit(lose ? EXIT_FAILURE : EXIT_SUCCESS);
 129 }