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