aboutsummaryrefslogtreecommitdiffstats
path: root/udev_utils_file.c
blob: f8518f64ade113b7df2f919e5bd6da161c3b2516 (plain)
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
131
132
133
134
135
136
137
138
139
140
/*
 * udev_utils_file.c - files operations
 *
 * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
 *
 *	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 version 2 of the License.
 * 
 *	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.,
 *	675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */


#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <dirent.h>
#include <sys/stat.h>
#include <sys/mman.h>

#include "udev_libc_wrapper.h"
#include "udev.h"
#include "logging.h"
#include "udev_utils.h"
#include "list.h"

int create_path(const char *path)
{
	char p[PATH_SIZE];
	char *pos;
	struct stat stats;

	strcpy (p, path);
	pos = strrchr(p, '/');
	if (pos == p || pos == NULL)
		return 0;

	while (pos[-1] == '/')
		pos--;

	pos[0] = '\0';

	dbg("stat '%s'\n", p);
	if (stat (p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR)
		return 0;

	if (create_path (p) != 0)
		return -1;

	dbg("mkdir '%s'\n", p);
	return mkdir(p, 0755);
}

/* Reset permissions on the device node, before unlinking it to make sure,
 * that permisions of possible hard links will be removed too.
 */
int unlink_secure(const char *filename)
{
	int retval;

	retval = chown(filename, 0, 0);
	if (retval)
		dbg("chown(%s, 0, 0) failed with error '%s'", filename, strerror(errno));

	retval = chmod(filename, 0000);
	if (retval)
		dbg("chmod(%s, 0000) failed with error '%s'", filename, strerror(errno));

	retval = unlink(filename);
	if (errno == ENOENT)
		retval = 0;

	if (retval)
		dbg("unlink(%s) failed with error '%s'", filename, strerror(errno));

	return retval;
}

int file_map(const char *filename, char **buf, size_t *bufsize)
{
	struct stat stats;
	int fd;

	fd = open(filename, O_RDONLY);
	if (fd < 0) {
		return -1;
	}

	if (fstat(fd, &stats) < 0) {
		close(fd);
		return -1;
	}

	*buf = mmap(NULL, stats.st_size, PROT_READ, MAP_SHARED, fd, 0);
	if (*buf == MAP_FAILED) {
		close(fd);
		return -1;
	}
	*bufsize = stats.st_size;

	close(fd);

	return 0;
}

void file_unmap(void *buf, size_t bufsize)
{
	munmap(buf, bufsize);
}

/* return number of chars until the next newline, skip escaped newline */
size_t buf_get_line(const char *buf, size_t buflen, size_t cur)
{
	int escape = 0;
	size_t count;

	for (count = cur; count < buflen; count++) {
		if (!escape && buf[count] == '\n')
			break;

		if (buf[count] == '\\')
			escape = 1;
		else
			escape = 0;
	}

	return count - cur;
}