1 /* Copyright (C) 1991-2022 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 Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the 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    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <errno.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 
23 
24 int
main(int argc,char ** argv)25 main (int argc, char **argv)
26 {
27   static const char hello[] = "Hello, world.\n";
28   static const char replace[] = "Hewwo, world.\n";
29   static const size_t replace_from = 2, replace_to = 4;
30   char filename[FILENAME_MAX];
31   char *name = strrchr (*argv, '/');
32   char buf[BUFSIZ];
33   FILE *f;
34   int lose = 0;
35 
36   if (name != NULL)
37     ++name;
38   else
39     name = *argv;
40 
41   (void) sprintf (filename, OBJPFX "%s.test", name);
42 
43   f = fopen (filename, "w+");
44   if (f == NULL)
45     {
46       perror (filename);
47       exit (1);
48     }
49 
50   (void) fputs (hello, f);
51   rewind (f);
52   (void) fgets (buf, sizeof (buf), f);
53   rewind (f);
54   (void) fputs (buf, f);
55   rewind (f);
56   {
57     size_t i;
58     for (i = 0; i < replace_from; ++i)
59       {
60 	int c = getc (f);
61 	if (c == EOF)
62 	  {
63 	    printf ("EOF at %Zu.\n", i);
64 	    lose = 1;
65 	    break;
66 	  }
67 	else if (c != hello[i])
68 	  {
69 	    printf ("Got '%c' instead of '%c' at %Zu.\n",
70 		    (unsigned char) c, hello[i], i);
71 	    lose = 1;
72 	    break;
73 	  }
74       }
75   }
76 
77   {
78     long int where = ftell (f);
79     if (where == (long int) replace_from)
80       {
81 	size_t i;
82 	for (i = replace_from; i < replace_to; ++i)
83 	  if (putc(replace[i], f) == EOF)
84 	    {
85 	      printf ("putc('%c') got %s at %Zu.\n",
86 		      replace[i], strerror (errno), i);
87 	      lose = 1;
88 	      break;
89 	    }
90       }
91     else if (where == -1L)
92       {
93 	printf ("ftell got %s (should be at %Zu).\n",
94 		strerror (errno), replace_from);
95 	lose = 1;
96       }
97     else
98       {
99 	printf ("ftell returns %lu; should be %Zu.\n", where, replace_from);
100 	lose = 1;
101       }
102   }
103 
104   if (!lose)
105     {
106       rewind (f);
107       if (fgets (buf, sizeof (buf), f) == NULL)
108 	{
109 	  printf ("fgets got %s.\n", strerror(errno));
110 	  lose = 1;
111 	}
112       else if (strcmp (buf, replace))
113 	{
114 	  printf ("Read \"%s\" instead of \"%s\".\n", buf, replace);
115 	  lose = 1;
116 	}
117     }
118 
119   if (lose)
120     printf ("Test FAILED!  Losing file is \"%s\".\n", filename);
121   else
122     {
123       (void) remove (filename);
124       puts ("Test succeeded.");
125     }
126 
127   return lose ? EXIT_FAILURE : EXIT_SUCCESS;
128 }
129