48399d081f7df1d85b91815f0560e1e78b27b0b3
[libav.git] / libavformat / avio.c
1 /*
2 * Unbuffered io for ffmpeg system
3 * Copyright (c) 2001 Fabrice Bellard
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /* needed for usleep() */
23 #define _XOPEN_SOURCE 600
24 #include <unistd.h>
25 #include "libavutil/avstring.h"
26 #include "libavcodec/opt.h"
27 #include "os_support.h"
28 #include "avformat.h"
29 #if CONFIG_NETWORK
30 #include "network.h"
31 #endif
32
33 #if LIBAVFORMAT_VERSION_MAJOR >= 53
34 /** @name Logging context. */
35 /*@{*/
36 static const char *urlcontext_to_name(void *ptr)
37 {
38 URLContext *h = (URLContext *)ptr;
39 if(h->prot) return h->prot->name;
40 else return "NULL";
41 }
42 static const AVOption options[] = {{NULL}};
43 static const AVClass urlcontext_class =
44 { "URLContext", urlcontext_to_name, options, LIBAVUTIL_VERSION_INT };
45 /*@}*/
46 #endif
47
48 static int default_interrupt_cb(void);
49
50 URLProtocol *first_protocol = NULL;
51 URLInterruptCB *url_interrupt_cb = default_interrupt_cb;
52
53 URLProtocol *av_protocol_next(URLProtocol *p)
54 {
55 if(p) return p->next;
56 else return first_protocol;
57 }
58
59 int av_register_protocol(URLProtocol *protocol)
60 {
61 URLProtocol **p;
62 p = &first_protocol;
63 while (*p != NULL) p = &(*p)->next;
64 *p = protocol;
65 protocol->next = NULL;
66 return 0;
67 }
68
69 #if LIBAVFORMAT_VERSION_MAJOR < 53
70 int register_protocol(URLProtocol *protocol)
71 {
72 return av_register_protocol(protocol);
73 }
74 #endif
75
76 int url_open_protocol (URLContext **puc, struct URLProtocol *up,
77 const char *filename, int flags)
78 {
79 URLContext *uc;
80 int err;
81
82 #if CONFIG_NETWORK
83 if (!ff_network_init())
84 return AVERROR(EIO);
85 #endif
86 uc = av_mallocz(sizeof(URLContext) + strlen(filename) + 1);
87 if (!uc) {
88 err = AVERROR(ENOMEM);
89 goto fail;
90 }
91 #if LIBAVFORMAT_VERSION_MAJOR >= 53
92 uc->av_class = &urlcontext_class;
93 #endif
94 uc->filename = (char *) &uc[1];
95 strcpy(uc->filename, filename);
96 uc->prot = up;
97 uc->flags = flags;
98 uc->is_streamed = 0; /* default = not streamed */
99 uc->max_packet_size = 0; /* default: stream file */
100 err = up->url_open(uc, filename, flags);
101 if (err < 0) {
102 av_free(uc);
103 goto fail;
104 }
105
106 //We must be careful here as url_seek() could be slow, for example for http
107 if( (flags & (URL_WRONLY | URL_RDWR))
108 || !strcmp(up->name, "file"))
109 if(!uc->is_streamed && url_seek(uc, 0, SEEK_SET) < 0)
110 uc->is_streamed= 1;
111 *puc = uc;
112 return 0;
113 fail:
114 *puc = NULL;
115 #if CONFIG_NETWORK
116 ff_network_close();
117 #endif
118 return err;
119 }
120
121 int url_open(URLContext **puc, const char *filename, int flags)
122 {
123 URLProtocol *up;
124 const char *p;
125 char proto_str[128], *q;
126
127 p = filename;
128 q = proto_str;
129 while (*p != '\0' && *p != ':') {
130 /* protocols can only contain alphabetic chars */
131 if (!isalpha(*p))
132 goto file_proto;
133 if ((q - proto_str) < sizeof(proto_str) - 1)
134 *q++ = *p;
135 p++;
136 }
137 /* if the protocol has length 1, we consider it is a dos drive */
138 if (*p == '\0' || is_dos_path(filename)) {
139 file_proto:
140 strcpy(proto_str, "file");
141 } else {
142 *q = '\0';
143 }
144
145 up = first_protocol;
146 while (up != NULL) {
147 if (!strcmp(proto_str, up->name))
148 return url_open_protocol (puc, up, filename, flags);
149 up = up->next;
150 }
151 *puc = NULL;
152 return AVERROR(ENOENT);
153 }
154
155 int url_read(URLContext *h, unsigned char *buf, int size)
156 {
157 int ret;
158 if (h->flags & URL_WRONLY)
159 return AVERROR(EIO);
160 ret = h->prot->url_read(h, buf, size);
161 return ret;
162 }
163
164 int url_read_complete(URLContext *h, unsigned char *buf, int size)
165 {
166 int ret, len;
167 int fast_retries = 5;
168
169 len = 0;
170 while (len < size) {
171 ret = url_read(h, buf+len, size-len);
172 if (ret == AVERROR(EAGAIN)) {
173 ret = 0;
174 if (fast_retries)
175 fast_retries--;
176 else
177 usleep(1000);
178 } else if (ret < 1)
179 return ret < 0 ? ret : len;
180 if (ret)
181 fast_retries = FFMAX(fast_retries, 2);
182 len += ret;
183 }
184 return len;
185 }
186
187 int url_write(URLContext *h, unsigned char *buf, int size)
188 {
189 int ret;
190 if (!(h->flags & (URL_WRONLY | URL_RDWR)))
191 return AVERROR(EIO);
192 /* avoid sending too big packets */
193 if (h->max_packet_size && size > h->max_packet_size)
194 return AVERROR(EIO);
195 ret = h->prot->url_write(h, buf, size);
196 return ret;
197 }
198
199 int64_t url_seek(URLContext *h, int64_t pos, int whence)
200 {
201 int64_t ret;
202
203 if (!h->prot->url_seek)
204 return AVERROR(ENOSYS);
205 ret = h->prot->url_seek(h, pos, whence & ~AVSEEK_FORCE);
206 return ret;
207 }
208
209 int url_close(URLContext *h)
210 {
211 int ret = 0;
212 if (!h) return 0; /* can happen when url_open fails */
213
214 if (h->prot->url_close)
215 ret = h->prot->url_close(h);
216 #if CONFIG_NETWORK
217 ff_network_close();
218 #endif
219 av_free(h);
220 return ret;
221 }
222
223 int url_exist(const char *filename)
224 {
225 URLContext *h;
226 if (url_open(&h, filename, URL_RDONLY) < 0)
227 return 0;
228 url_close(h);
229 return 1;
230 }
231
232 int64_t url_filesize(URLContext *h)
233 {
234 int64_t pos, size;
235
236 size= url_seek(h, 0, AVSEEK_SIZE);
237 if(size<0){
238 pos = url_seek(h, 0, SEEK_CUR);
239 if ((size = url_seek(h, -1, SEEK_END)) < 0)
240 return size;
241 size++;
242 url_seek(h, pos, SEEK_SET);
243 }
244 return size;
245 }
246
247 int url_get_file_handle(URLContext *h)
248 {
249 if (!h->prot->url_get_file_handle)
250 return -1;
251 return h->prot->url_get_file_handle(h);
252 }
253
254 int url_get_max_packet_size(URLContext *h)
255 {
256 return h->max_packet_size;
257 }
258
259 void url_get_filename(URLContext *h, char *buf, int buf_size)
260 {
261 av_strlcpy(buf, h->filename, buf_size);
262 }
263
264
265 static int default_interrupt_cb(void)
266 {
267 return 0;
268 }
269
270 void url_set_interrupt_cb(URLInterruptCB *interrupt_cb)
271 {
272 if (!interrupt_cb)
273 interrupt_cb = default_interrupt_cb;
274 url_interrupt_cb = interrupt_cb;
275 }
276
277 int av_url_read_pause(URLContext *h, int pause)
278 {
279 if (!h->prot->url_read_pause)
280 return AVERROR(ENOSYS);
281 return h->prot->url_read_pause(h, pause);
282 }
283
284 int64_t av_url_read_seek(URLContext *h,
285 int stream_index, int64_t timestamp, int flags)
286 {
287 if (!h->prot->url_read_seek)
288 return AVERROR(ENOSYS);
289 return h->prot->url_read_seek(h, stream_index, timestamp, flags);
290 }