2 * Copyright (c) 2003-2007 Tim Kientzle
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 #include "archive_platform.h"
27 __FBSDID("$FreeBSD: src/lib/libarchive/archive_read_open_filename.c,v 1.21 2008/02/19 06:10:48 kientzle Exp $");
29 #ifdef HAVE_SYS_STAT_H
54 struct read_file_data {
58 mode_t st_mode; /* Mode bits for opened file. */
59 char can_skip; /* This file supports skipping. */
60 char filename[1]; /* Must be last! */
63 static int file_close(struct archive *, void *);
64 static ssize_t file_read(struct archive *, void *, const void **buff);
65 #if ARCHIVE_API_VERSION < 2
66 static ssize_t file_skip(struct archive *, void *, size_t request);
68 static off_t file_skip(struct archive *, void *, off_t request);
72 archive_read_open_file(struct archive *a, const char *filename,
75 return (archive_read_open_filename(a, filename, block_size));
79 archive_read_open_filename(struct archive *a, const char *filename,
83 struct read_file_data *mine;
87 if (filename == NULL || filename[0] == '\0')
88 return (archive_read_open_fd(a, 0, block_size));
90 fd = open(filename, O_RDONLY | O_BINARY);
92 archive_set_error(a, errno, "Failed to open '%s'", filename);
93 return (ARCHIVE_FATAL);
95 if (fstat(fd, &st) != 0) {
96 archive_set_error(a, errno, "Can't stat '%s'", filename);
97 return (ARCHIVE_FATAL);
100 mine = (struct read_file_data *)malloc(sizeof(*mine) + strlen(filename));
101 b = malloc(block_size);
102 if (mine == NULL || b == NULL) {
103 archive_set_error(a, ENOMEM, "No memory");
106 return (ARCHIVE_FATAL);
108 strcpy(mine->filename, filename);
109 mine->block_size = block_size;
112 /* Remember mode so close can decide whether to flush. */
113 mine->st_mode = st.st_mode;
114 /* If we're reading a file from disk, ensure that we don't
115 overwrite it with an extracted file. */
116 if (S_ISREG(st.st_mode)) {
117 archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);
119 * Skip is a performance optimization for anything
120 * that supports lseek(). Generally, that only
121 * includes regular files and possibly raw disk
122 * devices, but there's no good portable way to detect
128 return (archive_read_open2(a, mine,
129 NULL, file_read, file_skip, file_close));
133 file_read(struct archive *a, void *client_data, const void **buff)
135 struct read_file_data *mine = (struct read_file_data *)client_data;
138 *buff = mine->buffer;
139 bytes_read = read(mine->fd, mine->buffer, mine->block_size);
140 if (bytes_read < 0) {
141 archive_set_error(a, errno, "Error reading '%s'",
147 #if ARCHIVE_API_VERSION < 2
149 file_skip(struct archive *a, void *client_data, size_t request)
152 file_skip(struct archive *a, void *client_data, off_t request)
155 struct read_file_data *mine = (struct read_file_data *)client_data;
156 off_t old_offset, new_offset;
158 if (!mine->can_skip) /* We can't skip, so ... */
159 return (0); /* ... skip zero bytes. */
161 /* Reduce request to the next smallest multiple of block_size */
162 request = (request / mine->block_size) * mine->block_size;
167 * Hurray for lazy evaluation: if the first lseek fails, the second
168 * one will not be executed.
170 if (((old_offset = lseek(mine->fd, 0, SEEK_CUR)) < 0) ||
171 ((new_offset = lseek(mine->fd, request, SEEK_CUR)) < 0))
173 /* If skip failed once, it will probably fail again. */
179 * Failure to lseek() can be caused by the file
180 * descriptor pointing to a pipe, socket or FIFO.
181 * Return 0 here, so the compression layer will use
182 * read()s instead to advance the file descriptor.
183 * It's slower of course, but works as well.
188 * There's been an error other than ESPIPE. This is most
189 * likely caused by a programmer error (too large request)
190 * or a corrupted archive file.
192 archive_set_error(a, errno, "Error seeking in '%s'",
196 return (new_offset - old_offset);
200 file_close(struct archive *a, void *client_data)
202 struct read_file_data *mine = (struct read_file_data *)client_data;
204 (void)a; /* UNUSED */
206 /* Only flush and close if open succeeded. */
209 * Sometimes, we should flush the input before closing.
210 * Regular files: faster to just close without flush.
211 * Devices: must not flush (user might need to
212 * read the "next" item on a non-rewind device).
213 * Pipes and sockets: must flush (otherwise, the
214 * program feeding the pipe or socket may complain).
215 * Here, I flush everything except for regular files and
218 if (!S_ISREG(mine->st_mode)
219 && !S_ISCHR(mine->st_mode)
220 && !S_ISBLK(mine->st_mode)) {
223 bytesRead = read(mine->fd, mine->buffer,
225 } while (bytesRead > 0);