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
|
/* Invoke fopen, but avoid some glitches.
Copyright (C) 2001, 2004, 2005, 2006 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 2, 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, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
/* Written by Paul Eggert. */
#include <config.h>
#include "stdio-safer.h"
#include <errno.h>
#include <unistd.h>
#include "unistd-safer.h"
#ifndef STDERR_FILENO
# define STDERR_FILENO 2
#endif
/* Like fopen, but do not return stdin, stdout, or stderr. */
FILE *
fopen_safer (char const *file, char const *mode)
{
FILE *fp = fopen (file, mode);
if (fp)
{
int fd = fileno (fp);
if (0 <= fd && fd <= STDERR_FILENO)
{
int f = dup_safer (fd);
if (f < 0)
{
int e = errno;
fclose (fp);
errno = e;
return NULL;
}
if (fclose (fp) != 0
|| ! (fp = fdopen (f, mode)))
{
int e = errno;
close (f);
errno = e;
return NULL;
}
}
}
return fp;
}
|
