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 #include "archive_platform_stat.h"
52
53 struct read_FILE_data {
54 FILE *f;
55 size_t block_size;
56 int64_t size;
57 void *buffer;
58 char can_skip;
59 };
60
61 static int FILE_close(struct archive *, void *);
62 static ssize_t FILE_read(struct archive *, void *, const void **buff);
63 static int64_t FILE_seek(struct archive *, void *, int64_t, int);
64 static int64_t FILE_skip(struct archive *, void *, int64_t);
65
66 int
archive_read_open_FILE(struct archive * a,FILE * f)67 archive_read_open_FILE(struct archive *a, FILE *f)
68 {
69 la_seek_stat_t st;
70 struct read_FILE_data *mine;
71 size_t block_size = 128 * 1024;
72 void *b;
73
74 archive_clear_error(a);
75 mine = calloc(1, sizeof(*mine));
76 b = malloc(block_size);
77 if (mine == NULL || b == NULL) {
78 archive_set_error(a, ENOMEM, "No memory");
79 free(mine);
80 free(b);
81 return (ARCHIVE_FATAL);
82 }
83 mine->block_size = block_size;
84 mine->buffer = b;
85 mine->f = f;
86 /*
87 * If we can't fstat() the file, it may just be that it's not
88 * a file. (On some platforms, FILE * objects can wrap I/O
89 * streams that don't support fileno()). As a result, fileno()
90 * should be used cautiously.)
91 */
92 if (la_seek_fstat(fileno(mine->f), &st) == 0 && S_ISREG(st.st_mode)) {
93 archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);
94 /* Enable the seek optimization only for regular files. */
95 mine->can_skip = 1;
96 mine->size = st.st_size;
97 }
98
99 #if defined(__CYGWIN__) || defined(_WIN32)
100 setmode(fileno(mine->f), O_BINARY);
101 #endif
102
103 archive_read_set_read_callback(a, FILE_read);
104 archive_read_set_skip_callback(a, FILE_skip);
105 archive_read_set_seek_callback(a, FILE_seek);
106 archive_read_set_close_callback(a, FILE_close);
107 archive_read_set_callback_data(a, mine);
108 return (archive_read_open1(a));
109 }
110
111 static ssize_t
FILE_read(struct archive * a,void * client_data,const void ** buff)112 FILE_read(struct archive *a, void *client_data, const void **buff)
113 {
114 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
115 size_t bytes_read;
116
117 *buff = mine->buffer;
118 bytes_read = fread(mine->buffer, 1, mine->block_size, mine->f);
119 if (bytes_read < mine->block_size && ferror(mine->f)) {
120 archive_set_error(a, errno, "Error reading file");
121 }
122 return (bytes_read);
123 }
124
125 static int64_t
FILE_skip(struct archive * a,void * client_data,int64_t request)126 FILE_skip(struct archive *a, void *client_data, int64_t request)
127 {
128 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
129 #if HAVE__FSEEKI64
130 int64_t skip = request;
131 #elif HAVE_FSEEKO
132 off_t skip = (off_t)request;
133 #else
134 long skip = (long)request;
135 #endif
136 int64_t old_offset, new_offset = -1;
137 int skip_bits = sizeof(skip) * 8 - 1;
138
139 (void)a; /* UNUSED */
140
141 /*
142 * If we can't skip, return 0 as the amount we did step and
143 * the caller will work around by reading and discarding.
144 */
145 if (!mine->can_skip)
146 return (0);
147 if (request == 0)
148 return (0);
149
150 /* If request is too big for a long or an off_t, reduce it. */
151 if (sizeof(request) > sizeof(skip)) {
152 const int64_t max_skip =
153 (((int64_t)1 << (skip_bits - 1)) - 1) * 2 + 1;
154 if (request > max_skip)
155 skip = max_skip;
156 }
157
158 #ifdef __ANDROID__
159 /* fileno() isn't safe on all platforms ... see above. */
160 old_offset = lseek(fileno(mine->f), 0, SEEK_CUR);
161 #elif HAVE__FSEEKI64
162 old_offset = _ftelli64(mine->f);
163 #elif HAVE_FSEEKO
164 old_offset = ftello(mine->f);
165 #else
166 old_offset = ftell(mine->f);
167 #endif
168 if (old_offset >= 0) {
169 if (old_offset < mine->size &&
170 skip <= mine->size - old_offset) {
171 #ifdef __ANDROID__
172 new_offset = lseek(fileno(mine->f), skip, SEEK_CUR);
173 #elif HAVE__FSEEKI64
174 if (_fseeki64(mine->f, skip, SEEK_CUR) == 0)
175 new_offset = _ftelli64(mine->f);
176 #elif HAVE_FSEEKO
177 if (fseeko(mine->f, skip, SEEK_CUR) == 0)
178 new_offset = ftello(mine->f);
179 #else
180 if (fseek(mine->f, skip, SEEK_CUR) == 0)
181 new_offset = ftell(mine->f);
182 #endif
183 if (new_offset >= 0)
184 return (new_offset - old_offset);
185 }
186 }
187
188 mine->can_skip = 0;
189 return (0);
190 }
191
192 /*
193 * TODO: Store the offset and use it in the read callback.
194 */
195 static int64_t
FILE_seek(struct archive * a,void * client_data,int64_t request,int whence)196 FILE_seek(struct archive *a, void *client_data, int64_t request, int whence)
197 {
198 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
199 #if HAVE__FSEEKI64
200 int64_t seek = request;
201 #elif HAVE_FSEEKO
202 off_t seek = (off_t)request;
203 #else
204 long seek = (long)request;
205 #endif
206 int seek_bits = sizeof(seek) * 8 - 1;
207 (void)a; /* UNUSED */
208
209 /* Do not perform a seek which cannot be fulfilled. */
210 if (sizeof(request) > sizeof(seek)) {
211 const int64_t max_seek =
212 (((int64_t)1 << (seek_bits - 1)) - 1) * 2 + 1;
213 const int64_t min_seek = ~max_seek;
214 if (request < min_seek || request > max_seek) {
215 errno = EOVERFLOW;
216 goto err;
217 }
218 }
219
220 #ifdef __ANDROID__
221 /* Newer Android versions have fseeko...to meditate. */
222 int64_t ret = lseek(fileno(mine->f), seek, whence);
223 if (ret >= 0) {
224 return ret;
225 }
226 #elif HAVE__FSEEKI64
227 if (_fseeki64(mine->f, seek, whence) == 0) {
228 return _ftelli64(mine->f);
229 }
230 #elif HAVE_FSEEKO
231 if (fseeko(mine->f, seek, whence) == 0) {
232 return ftello(mine->f);
233 }
234 #else
235 if (fseek(mine->f, seek, whence) == 0) {
236 return ftell(mine->f);
237 }
238 #endif
239 /* If we arrive here, the input is corrupted or truncated so fail. */
240 err:
241 archive_set_error(a, errno, "Error seeking in FILE* pointer");
242 return (ARCHIVE_FATAL);
243 }
244
245 static int
FILE_close(struct archive * a,void * client_data)246 FILE_close(struct archive *a, void *client_data)
247 {
248 struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
249
250 (void)a; /* UNUSED */
251 free(mine->buffer);
252 free(mine);
253 return (ARCHIVE_OK);
254 }
255