Implement url_open_protocol(), which is basiclly the former url_open()
[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 #include "libavutil/avstring.h"
23 #include "libavcodec/opt.h"
24 #include "avformat.h"
25
26 #if LIBAVFORMAT_VERSION_MAJOR >= 53
27 /** @name Logging context. */
28 /*@{*/
29 static const char *urlcontext_to_name(void *ptr)
30 {
31 URLContext *h = (URLContext *)ptr;
32 if(h->prot) return h->prot->name;
33 else return "NULL";
34 }
35 static const AVOption options[] = {{NULL}};
36 static const AVClass urlcontext_class =
37 { "URLContext", urlcontext_to_name, options };
38 /*@}*/
39 #endif
40
41 static int default_interrupt_cb(void);
42
43 URLProtocol *first_protocol = NULL;
44 URLInterruptCB *url_interrupt_cb = default_interrupt_cb;
45
46 URLProtocol *av_protocol_next(URLProtocol *p)
47 {
48 if(p) return p->next;
49 else return first_protocol;
50 }
51
52 int register_protocol(URLProtocol *protocol)
53 {
54 URLProtocol **p;
55 p = &first_protocol;
56 while (*p != NULL) p = &(*p)->next;
57 *p = protocol;
58 protocol->next = NULL;
59 return 0;
60 }
61
62 int url_open_protocol (URLContext **puc, struct URLProtocol *up,
63 const char *filename, int flags)
64 {
65 URLContext *uc;
66 int err;
67
68 uc = av_malloc(sizeof(URLContext) + strlen(filename) + 1);
69 if (!uc) {
70 err = AVERROR(ENOMEM);
71 goto fail;
72 }
73 #if LIBAVFORMAT_VERSION_MAJOR >= 53
74 uc->av_class = &urlcontext_class;
75 #endif
76 uc->filename = (char *) &uc[1];
77 strcpy(uc->filename, filename);
78 uc->prot = up;
79 uc->flags = flags;
80 uc->is_streamed = 0; /* default = not streamed */
81 uc->max_packet_size = 0; /* default: stream file */
82 err = up->url_open(uc, filename, flags);
83 if (err < 0) {
84 av_free(uc);
85 *puc = NULL;
86 return err;
87 }
88
89 //We must be carefull here as url_seek() could be slow, for example for http
90 if( (flags & (URL_WRONLY | URL_RDWR))
91 || !strcmp(up->name, "file"))
92 if(!uc->is_streamed && url_seek(uc, 0, SEEK_SET) < 0)
93 uc->is_streamed= 1;
94 *puc = uc;
95 return 0;
96 fail:
97 *puc = NULL;
98 return err;
99 }
100
101 int url_open(URLContext **puc, const char *filename, int flags)
102 {
103 URLProtocol *up;
104 const char *p;
105 char proto_str[128], *q;
106
107 p = filename;
108 q = proto_str;
109 while (*p != '\0' && *p != ':') {
110 /* protocols can only contain alphabetic chars */
111 if (!isalpha(*p))
112 goto file_proto;
113 if ((q - proto_str) < sizeof(proto_str) - 1)
114 *q++ = *p;
115 p++;
116 }
117 /* if the protocol has length 1, we consider it is a dos drive */
118 if (*p == '\0' || (q - proto_str) <= 1) {
119 file_proto:
120 strcpy(proto_str, "file");
121 } else {
122 *q = '\0';
123 }
124
125 up = first_protocol;
126 while (up != NULL) {
127 if (!strcmp(proto_str, up->name))
128 return url_open_protocol (puc, up, filename, flags);
129 up = up->next;
130 }
131 *puc = NULL;
132 return AVERROR(ENOENT);
133 }
134
135 int url_read(URLContext *h, unsigned char *buf, int size)
136 {
137 int ret;
138 if (h->flags & URL_WRONLY)
139 return AVERROR(EIO);
140 ret = h->prot->url_read(h, buf, size);
141 return ret;
142 }
143
144 int url_write(URLContext *h, unsigned char *buf, int size)
145 {
146 int ret;
147 if (!(h->flags & (URL_WRONLY | URL_RDWR)))
148 return AVERROR(EIO);
149 /* avoid sending too big packets */
150 if (h->max_packet_size && size > h->max_packet_size)
151 return AVERROR(EIO);
152 ret = h->prot->url_write(h, buf, size);
153 return ret;
154 }
155
156 offset_t url_seek(URLContext *h, offset_t pos, int whence)
157 {
158 offset_t ret;
159
160 if (!h->prot->url_seek)
161 return AVERROR(EPIPE);
162 ret = h->prot->url_seek(h, pos, whence);
163 return ret;
164 }
165
166 int url_close(URLContext *h)
167 {
168 int ret = 0;
169 if (!h) return 0; /* can happen when url_open fails */
170
171 if (h->prot->url_close)
172 ret = h->prot->url_close(h);
173 av_free(h);
174 return ret;
175 }
176
177 int url_exist(const char *filename)
178 {
179 URLContext *h;
180 if (url_open(&h, filename, URL_RDONLY) < 0)
181 return 0;
182 url_close(h);
183 return 1;
184 }
185
186 offset_t url_filesize(URLContext *h)
187 {
188 offset_t pos, size;
189
190 size= url_seek(h, 0, AVSEEK_SIZE);
191 if(size<0){
192 pos = url_seek(h, 0, SEEK_CUR);
193 if ((size = url_seek(h, -1, SEEK_END)) < 0)
194 return size;
195 size++;
196 url_seek(h, pos, SEEK_SET);
197 }
198 return size;
199 }
200
201 int url_get_max_packet_size(URLContext *h)
202 {
203 return h->max_packet_size;
204 }
205
206 void url_get_filename(URLContext *h, char *buf, int buf_size)
207 {
208 av_strlcpy(buf, h->filename, buf_size);
209 }
210
211
212 static int default_interrupt_cb(void)
213 {
214 return 0;
215 }
216
217 void url_set_interrupt_cb(URLInterruptCB *interrupt_cb)
218 {
219 if (!interrupt_cb)
220 interrupt_cb = default_interrupt_cb;
221 url_interrupt_cb = interrupt_cb;
222 }
223
224 int av_url_read_pause(URLContext *h, int pause)
225 {
226 if (!h->prot->url_read_pause)
227 return AVERROR(ENOSYS);
228 return h->prot->url_read_pause(h, pause);
229 }
230
231 offset_t av_url_read_seek(URLContext *h,
232 int stream_index, int64_t timestamp, int flags)
233 {
234 if (!h->prot->url_read_seek)
235 return AVERROR(ENOSYS);
236 return h->prot->url_read_seek(h, stream_index, timestamp, flags);
237 }