1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
/* Test of freading() function.
Copyright (C) 2007-2020 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>, 2007. */
#include <config.h>
/* None of the files accessed by this test are large, so disable the
fseek link warning if we are not using the gnulib fseek module. */
#define _GL_NO_LARGE_FILES
#include "freading.h"
#include <stdio.h>
#include "macros.h"
#define TESTFILE "t-freading.tmp"
int
main (void)
{
FILE *fp;
/* Create a file with some contents. Write-only file is never reading. */
fp = fopen (TESTFILE, "w");
ASSERT (fp);
ASSERT (!freading (fp));
ASSERT (fwrite ("foobarsh", 1, 8, fp) == 8);
ASSERT (!freading (fp));
ASSERT (fclose (fp) == 0);
/* Open it in read-only mode. Read-only file is always reading. */
fp = fopen (TESTFILE, "r");
ASSERT (fp);
ASSERT (freading (fp));
ASSERT (fgetc (fp) == 'f');
ASSERT (freading (fp));
ASSERT (fseek (fp, 2, SEEK_CUR) == 0);
ASSERT (freading (fp));
ASSERT (fgetc (fp) == 'b');
ASSERT (freading (fp));
fflush (fp);
ASSERT (freading (fp));
ASSERT (fgetc (fp) == 'a');
ASSERT (freading (fp));
ASSERT (fseek (fp, 0, SEEK_END) == 0);
ASSERT (freading (fp));
ASSERT (fclose (fp) == 0);
/* Open it in read-write mode. POSIX requires a reposition (fseek,
fsetpos, rewind) or EOF when transitioning from read to write;
freading is only deterministic after input or output, but this
test case should be portable even on open, after reposition, and
at EOF. */
/* First a scenario with only fgetc, fseek, fputc. */
fp = fopen (TESTFILE, "r+");
ASSERT (fp);
ASSERT (!freading (fp));
ASSERT (fgetc (fp) == 'f');
ASSERT (freading (fp));
ASSERT (fseek (fp, 2, SEEK_CUR) == 0);
/* freading (fp) is undefined here, but fwriting (fp) is false. */
ASSERT (fgetc (fp) == 'b');
ASSERT (freading (fp));
/* This fseek call is necessary when switching from reading to writing.
See the description of fopen(), ISO C 99 7.19.5.3.(6). */
ASSERT (fseek (fp, 0, SEEK_CUR) == 0);
/* freading (fp) is undefined here, but fwriting (fp) is false. */
ASSERT (fputc ('x', fp) == 'x');
ASSERT (!freading (fp));
ASSERT (fseek (fp, 0, SEEK_END) == 0);
/* freading (fp) is undefined here, because on some implementations (e.g.
glibc) fseek causes a buffer to be read.
fwriting (fp) is undefined as well. */
ASSERT (fclose (fp) == 0);
/* Open it in read-write mode. POSIX requires a reposition (fseek,
fsetpos, rewind) or EOF when transitioning from read to write;
freading is only deterministic after input or output, but this
test case should be portable even on open, after reposition, and
at EOF. */
/* Here a scenario that includes fflush. */
fp = fopen (TESTFILE, "r+");
ASSERT (fp);
ASSERT (!freading (fp));
ASSERT (fgetc (fp) == 'f');
ASSERT (freading (fp));
ASSERT (fseek (fp, 2, SEEK_CUR) == 0);
/* freading (fp) is undefined here, but fwriting (fp) is false. */
ASSERT (fgetc (fp) == 'b');
ASSERT (freading (fp));
fflush (fp);
/* freading (fp) is undefined here, but fwriting (fp) is false. */
ASSERT (fgetc (fp) == 'x');
ASSERT (freading (fp));
/* This fseek call is necessary when switching from reading to writing.
See the description of fopen(), ISO C 99 7.19.5.3.(6). */
ASSERT (fseek (fp, 0, SEEK_CUR) == 0);
/* freading (fp) is undefined here, but fwriting (fp) is false. */
ASSERT (fputc ('z', fp) == 'z');
ASSERT (!freading (fp));
ASSERT (fseek (fp, 0, SEEK_END) == 0);
/* freading (fp) is undefined here, because on some implementations (e.g.
glibc) fseek causes a buffer to be read.
fwriting (fp) is undefined as well. */
ASSERT (fclose (fp) == 0);
/* Open it in append mode. Write-only file is never reading. */
fp = fopen (TESTFILE, "a");
ASSERT (fp);
ASSERT (!freading (fp));
ASSERT (fwrite ("bla", 1, 3, fp) == 3);
ASSERT (!freading (fp));
ASSERT (fclose (fp) == 0);
ASSERT (remove (TESTFILE) == 0);
return 0;
}
|
