1 /*-
2 * Copyright (c) 2003-2007 Tim Kientzle
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
13 *
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.
24 */
25
26 #include "archive_platform.h"
27
28 #ifdef HAVE_SYS_STAT_H
29 #include <sys/stat.h>
30 #endif
31 #ifdef HAVE_ERRNO_H
32 #include <errno.h>
33 #endif
34 #ifdef HAVE_FCNTL_H
35 #include <fcntl.h>
36 #endif
37 #ifdef HAVE_IO_H
38 #include <io.h>
39 #endif
40 #ifdef HAVE_STDLIB_H
41 #include <stdlib.h>
42 #endif
43 #ifdef HAVE_STRING_H
44 #include <string.h>
45 #endif
46 #ifdef HAVE_UNISTD_H
47 #include <unistd.h>
48 #endif
49
50 #include "archive.h"
51
52 struct read_FILE_data {
53 FILE *f;
54 size_t block_size;
55 int64_t size;
56 void *buffer;
57 char can_skip;
58 };
59
60 static int FILE_close(struct archive *, void *);
61 static ssize_t FILE_read(struct archive *, void *, const void **buff);
62 static int64_t FILE_seek(struct archive *, void *, int64_t, int);
63 static int64_t FILE_skip(struct archive *, void *, int64_t);
64
65 int
archive_read_open_FILE(struct archive * a,FILE * f)66 archive_read_open_FILE(struct archive *a, FILE *f)
67 {
68 struct stat st;
69 struct read_FILE_data *mine;
70 size_t block_size = 128 * 1024;
71 void *b;
72
73 archive_clear_error(a);
74 mine = calloc(1, sizeof(*mine));
75 b = malloc(block_size);
76 if (mine == NULL || b == NULL) {
77 archive_set_error(a, ENOMEM, "No memory");
78 free(mine);
79 free(b);
80 return (ARCHIVE_FATAL);
81 }
82 mine->block_size = block_size;
83 mine->buffer = b;
84 mine->f = f;
85 /*
86 * If we can't fstat() the file, it may just be that it's not
87 * a file. (On some platforms, FILE * objects can wrap I/O
88 * streams that don't support fileno()). As a result, fileno()
89 * should be used cautiously.)
90 */
91 if (fstat(fileno(mine->f), &st) == 0 && S_ISREG(st.st_mode)) {
92 archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);
93 /* Enable the seek optimization only for regular files. */
94 mine->can_skip = 1;
95 mine->size = st.st_size;
96 }
97
98 #if defined(__CYGWIN__) || defined(_WIN32)
99 setmode(fileno(mine->f), O_BINARY);
100 #endif
101
102 archive_read_set_read_callback(a, FILE_read);
103 archive_read_set_skip_callback(a, FILE_skip);
104 archive_read_set_seek_callback(a, FILE_seek);
105 archive_read_set_close_callback(a, FILE_close);
106 archive_read_set_callback_data(a, mine);
107 return (archive_read_open1(a));
108 }
109
110 static ssize_t
FILE_read(struct archive * a,void * client_data,const void ** buff)111 FILE_read(struct archive *a, void *client_data, const void **buff)
112 {
113 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
114 size_t bytes_read;
115
116 *buff = mine->buffer;
117 bytes_read = fread(mine->buffer, 1, mine->block_size, mine->f);
118 if (bytes_read < mine->block_size && ferror(mine->f)) {
119 archive_set_error(a, errno, "Error reading file");
120 }
121 return (bytes_read);
122 }
123
124 static int64_t
FILE_skip(struct archive * a,void * client_data,int64_t request)125 FILE_skip(struct archive *a, void *client_data, int64_t request)
126 {
127 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
128 #if HAVE__FSEEKI64
129 int64_t skip = request;
130 #elif HAVE_FSEEKO
131 off_t skip = (off_t)request;
132 #else
133 long skip = (long)request;
134 #endif
135 int64_t old_offset, new_offset = -1;
136 int skip_bits = sizeof(skip) * 8 - 1;
137
138 (void)a; /* UNUSED */
139
140 /*
141 * If we can't skip, return 0 as the amount we did step and
142 * the caller will work around by reading and discarding.
143 */
144 if (!mine->can_skip)
145 return (0);
146 if (request == 0)
147 return (0);
148
149 /* If request is too big for a long or an off_t, reduce it. */
150 if (sizeof(request) > sizeof(skip)) {
151 const int64_t max_skip =
152 (((int64_t)1 << (skip_bits - 1)) - 1) * 2 + 1;
153 if (request > max_skip)
154 skip = max_skip;
155 }
156
157 #ifdef __ANDROID__
158 /* fileno() isn't safe on all platforms ... see above. */
159 old_offset = lseek(fileno(mine->f), 0, SEEK_CUR);
160 #elif HAVE__FSEEKI64
161 old_offset = _ftelli64(mine->f);
162 #elif HAVE_FSEEKO
163 old_offset = ftello(mine->f);
164 #else
165 old_offset = ftell(mine->f);
166 #endif
167 if (old_offset >= 0) {
168 if (old_offset < mine->size &&
169 skip <= mine->size - old_offset) {
170 #ifdef __ANDROID__
171 new_offset = lseek(fileno(mine->f), skip, SEEK_CUR);
172 #elif HAVE__FSEEKI64
173 if (_fseeki64(mine->f, skip, SEEK_CUR) == 0)
174 new_offset = _ftelli64(mine->f);
175 #elif HAVE_FSEEKO
176 if (fseeko(mine->f, skip, SEEK_CUR) == 0)
177 new_offset = ftello(mine->f);
178 #else
179 if (fseek(mine->f, skip, SEEK_CUR) == 0)
180 new_offset = ftell(mine->f);
181 #endif
182 if (new_offset >= 0)
183 return (new_offset - old_offset);
184 }
185 }
186
187 mine->can_skip = 0;
188 return (0);
189 }
190
191 /*
192 * TODO: Store the offset and use it in the read callback.
193 */
194 static int64_t
FILE_seek(struct archive * a,void * client_data,int64_t request,int whence)195 FILE_seek(struct archive *a, void *client_data, int64_t request, int whence)
196 {
197 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
198 #if HAVE__FSEEKI64
199 int64_t seek = request;
200 #elif HAVE_FSEEKO
201 off_t seek = (off_t)request;
202 #else
203 long seek = (long)request;
204 #endif
205 int seek_bits = sizeof(seek) * 8 - 1;
206 (void)a; /* UNUSED */
207
208 /* Reduce a request that would overflow the 'seek' variable. */
209 if (sizeof(request) > sizeof(seek)) {
210 const int64_t max_seek =
211 (((int64_t)1 << (seek_bits - 1)) - 1) * 2 + 1;
212 const int64_t min_seek = ~max_seek;
213 if (request > max_seek)
214 seek = max_seek;
215 else if (request < min_seek)
216 seek = min_seek;
217 }
218
219 #ifdef __ANDROID__
220 /* Newer Android versions have fseeko...to meditate. */
221 int64_t ret = lseek(fileno(mine->f), seek, whence);
222 if (ret >= 0) {
223 return ret;
224 }
225 #elif HAVE__FSEEKI64
226 if (_fseeki64(mine->f, seek, whence) == 0) {
227 return _ftelli64(mine->f);
228 }
229 #elif HAVE_FSEEKO
230 if (fseeko(mine->f, seek, whence) == 0) {
231 return ftello(mine->f);
232 }
233 #else
234 if (fseek(mine->f, seek, whence) == 0) {
235 return ftell(mine->f);
236 }
237 #endif
238 /* If we arrive here, the input is corrupted or truncated so fail. */
239 archive_set_error(a, errno, "Error seeking in FILE* pointer");
240 return (ARCHIVE_FATAL);
241 }
242
243 static int
FILE_close(struct archive * a,void * client_data)244 FILE_close(struct archive *a, void *client_data)
245 {
246 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
247
248 (void)a; /* UNUSED */
249 free(mine->buffer);
250 free(mine);
251 return (ARCHIVE_OK);
252 }
253