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
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
|
/*-
* Copyright (c) 2003-2007 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "archive_platform.h"
__FBSDID("$FreeBSD: head/lib/libarchive/archive_read_open_fd.c 201103 2009-12-28 03:13:49Z kientzle $");
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_IO_H
#include <io.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "archive.h"
struct read_fd_data {
int fd;
size_t block_size;
char use_lseek;
void *buffer;
};
static int file_close(struct archive *, void *);
static ssize_t file_read(struct archive *, void *, const void **buff);
static int64_t file_seek(struct archive *, void *, int64_t request, int);
static int64_t file_skip(struct archive *, void *, int64_t request);
int
archive_read_open_fd(struct archive *a, int fd, size_t block_size)
{
struct stat st;
struct read_fd_data *mine;
void *b;
archive_clear_error(a);
if (fstat(fd, &st) != 0) {
archive_set_error(a, errno, "Can't stat fd %d", fd);
return (ARCHIVE_FATAL);
}
mine = (struct read_fd_data *)calloc(1, sizeof(*mine));
b = malloc(block_size);
if (mine == NULL || b == NULL) {
archive_set_error(a, ENOMEM, "No memory");
free(mine);
free(b);
return (ARCHIVE_FATAL);
}
mine->block_size = block_size;
mine->buffer = b;
mine->fd = fd;
/*
* Skip support is a performance optimization for anything
* that supports lseek(). On FreeBSD, only regular files and
* raw disk devices support lseek() and there's no portable
* way to determine if a device is a raw disk device, so we
* only enable this optimization for regular files.
*/
if (S_ISREG(st.st_mode)) {
archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);
mine->use_lseek = 1;
}
#if defined(__CYGWIN__) || defined(_WIN32)
setmode(mine->fd, O_BINARY);
#endif
archive_read_set_read_callback(a, file_read);
archive_read_set_skip_callback(a, file_skip);
archive_read_set_seek_callback(a, file_seek);
archive_read_set_close_callback(a, file_close);
archive_read_set_callback_data(a, mine);
return (archive_read_open1(a));
}
static ssize_t
file_read(struct archive *a, void *client_data, const void **buff)
{
struct read_fd_data *mine = (struct read_fd_data *)client_data;
ssize_t bytes_read;
*buff = mine->buffer;
for (;;) {
bytes_read = read(mine->fd, mine->buffer, mine->block_size);
if (bytes_read < 0) {
if (errno == EINTR)
continue;
archive_set_error(a, errno, "Error reading fd %d",
mine->fd);
}
return (bytes_read);
}
}
static int64_t
file_skip(struct archive *a, void *client_data, int64_t request)
{
struct read_fd_data *mine = (struct read_fd_data *)client_data;
int64_t skip = request;
int64_t old_offset, new_offset;
int skip_bits = sizeof(skip) * 8 - 1; /* off_t is a signed type. */
if (!mine->use_lseek)
return (0);
/* Reduce a request that would overflow the 'skip' variable. */
if (sizeof(request) > sizeof(skip)) {
int64_t max_skip =
(((int64_t)1 << (skip_bits - 1)) - 1) * 2 + 1;
if (request > max_skip)
skip = max_skip;
}
/* Reduce request to the next smallest multiple of block_size */
request = (request / mine->block_size) * mine->block_size;
if (request == 0)
return (0);
if (((old_offset = lseek(mine->fd, 0, SEEK_CUR)) >= 0) &&
((new_offset = lseek(mine->fd, skip, SEEK_CUR)) >= 0))
return (new_offset - old_offset);
/* If seek failed once, it will probably fail again. */
mine->use_lseek = 0;
/* Let libarchive recover with read+discard. */
if (errno == ESPIPE)
return (0);
/*
* There's been an error other than ESPIPE. This is most
* likely caused by a programmer error (too large request)
* or a corrupted archive file.
*/
archive_set_error(a, errno, "Error seeking");
return (-1);
}
/*
* TODO: Store the offset and use it in the read callback.
*/
static int64_t
file_seek(struct archive *a, void *client_data, int64_t request, int whence)
{
struct read_fd_data *mine = (struct read_fd_data *)client_data;
int64_t r;
/* We use off_t here because lseek() is declared that way. */
/* See above for notes about when off_t is less than 64 bits. */
r = lseek(mine->fd, request, whence);
if (r >= 0)
return r;
if (errno == ESPIPE) {
archive_set_error(a, errno,
"A file descriptor(%d) is not seekable(PIPE)", mine->fd);
return (ARCHIVE_FAILED);
} else {
/* If the input is corrupted or truncated, fail. */
archive_set_error(a, errno,
"Error seeking in a file descriptor(%d)", mine->fd);
return (ARCHIVE_FATAL);
}
}
static int
file_close(struct archive *a, void *client_data)
{
struct read_fd_data *mine = (struct read_fd_data *)client_data;
(void)a; /* UNUSED */
free(mine->buffer);
free(mine);
return (ARCHIVE_OK);
}
|
