lavf: deprecate av_read_packet().
[libav.git] / libavformat / rtpdec_asf.c
1 /*
2 * Microsoft RTP/ASF support.
3 * Copyright (c) 2008 Ronald S. Bultje
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * @brief Microsoft RTP/ASF support
25 * @author Ronald S. Bultje <rbultje@ronald.bitfreak.net>
26 */
27
28 #include "libavutil/base64.h"
29 #include "libavutil/avstring.h"
30 #include "libavutil/intreadwrite.h"
31 #include "rtp.h"
32 #include "rtpdec_formats.h"
33 #include "rtsp.h"
34 #include "asf.h"
35 #include "avio_internal.h"
36 #include "internal.h"
37
38 /**
39 * From MSDN 2.2.1.4, we learn that ASF data packets over RTP should not
40 * contain any padding. Unfortunately, the header min/max_pktsize are not
41 * updated (thus making min_pktsize invalid). Here, we "fix" these faulty
42 * min_pktsize values in the ASF file header.
43 * @return 0 on success, <0 on failure (currently -1).
44 */
45 static int rtp_asf_fix_header(uint8_t *buf, int len)
46 {
47 uint8_t *p = buf, *end = buf + len;
48
49 if (len < sizeof(ff_asf_guid) * 2 + 22 ||
50 memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) {
51 return -1;
52 }
53 p += sizeof(ff_asf_guid) + 14;
54 do {
55 uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid));
56 if (memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {
57 if (chunksize > end - p)
58 return -1;
59 p += chunksize;
60 continue;
61 }
62
63 /* skip most of the file header, to min_pktsize */
64 p += 6 * 8 + 3 * 4 + sizeof(ff_asf_guid) * 2;
65 if (p + 8 <= end && AV_RL32(p) == AV_RL32(p + 4)) {
66 /* and set that to zero */
67 AV_WL32(p, 0);
68 return 0;
69 }
70 break;
71 } while (end - p >= sizeof(ff_asf_guid) + 8);
72
73 return -1;
74 }
75
76 /**
77 * The following code is basically a buffered AVIOContext,
78 * with the added benefit of returning -EAGAIN (instead of 0)
79 * on packet boundaries, such that the ASF demuxer can return
80 * safely and resume business at the next packet.
81 */
82 static int packetizer_read(void *opaque, uint8_t *buf, int buf_size)
83 {
84 return AVERROR(EAGAIN);
85 }
86
87 static void init_packetizer(AVIOContext *pb, uint8_t *buf, int len)
88 {
89 ffio_init_context(pb, buf, len, 0, NULL, packetizer_read, NULL, NULL);
90
91 /* this "fills" the buffer with its current content */
92 pb->pos = len;
93 pb->buf_end = buf + len;
94 }
95
96 int ff_wms_parse_sdp_a_line(AVFormatContext *s, const char *p)
97 {
98 int ret = 0;
99 if (av_strstart(p, "pgmpu:data:application/vnd.ms.wms-hdr.asfv1;base64,", &p)) {
100 AVIOContext pb;
101 RTSPState *rt = s->priv_data;
102 int len = strlen(p) * 6 / 8;
103 char *buf = av_mallocz(len);
104 av_base64_decode(buf, p, len);
105
106 if (rtp_asf_fix_header(buf, len) < 0)
107 av_log(s, AV_LOG_ERROR,
108 "Failed to fix invalid RTSP-MS/ASF min_pktsize\n");
109 init_packetizer(&pb, buf, len);
110 if (rt->asf_ctx) {
111 avformat_close_input(&rt->asf_ctx);
112 }
113 if (!(rt->asf_ctx = avformat_alloc_context()))
114 return AVERROR(ENOMEM);
115 rt->asf_ctx->pb = &pb;
116 ret = avformat_open_input(&rt->asf_ctx, "", &ff_asf_demuxer, NULL);
117 if (ret < 0)
118 return ret;
119 av_dict_copy(&s->metadata, rt->asf_ctx->metadata, 0);
120 rt->asf_pb_pos = avio_tell(&pb);
121 av_free(buf);
122 rt->asf_ctx->pb = NULL;
123 }
124 return ret;
125 }
126
127 static int asfrtp_parse_sdp_line(AVFormatContext *s, int stream_index,
128 PayloadContext *asf, const char *line)
129 {
130 if (av_strstart(line, "stream:", &line)) {
131 RTSPState *rt = s->priv_data;
132
133 s->streams[stream_index]->id = strtol(line, NULL, 10);
134
135 if (rt->asf_ctx) {
136 int i;
137
138 for (i = 0; i < rt->asf_ctx->nb_streams; i++) {
139 if (s->streams[stream_index]->id == rt->asf_ctx->streams[i]->id) {
140 *s->streams[stream_index]->codec =
141 *rt->asf_ctx->streams[i]->codec;
142 rt->asf_ctx->streams[i]->codec->extradata_size = 0;
143 rt->asf_ctx->streams[i]->codec->extradata = NULL;
144 avpriv_set_pts_info(s->streams[stream_index], 32, 1, 1000);
145 }
146 }
147 }
148 }
149
150 return 0;
151 }
152
153 struct PayloadContext {
154 AVIOContext *pktbuf, pb;
155 uint8_t *buf;
156 };
157
158 /**
159 * @return 0 when a packet was written into /p pkt, and no more data is left;
160 * 1 when a packet was written into /p pkt, and more packets might be left;
161 * <0 when not enough data was provided to return a full packet, or on error.
162 */
163 static int asfrtp_parse_packet(AVFormatContext *s, PayloadContext *asf,
164 AVStream *st, AVPacket *pkt,
165 uint32_t *timestamp,
166 const uint8_t *buf, int len, int flags)
167 {
168 AVIOContext *pb = &asf->pb;
169 int res, mflags, len_off;
170 RTSPState *rt = s->priv_data;
171
172 if (!rt->asf_ctx)
173 return -1;
174
175 if (len > 0) {
176 int off, out_len = 0;
177
178 if (len < 4)
179 return -1;
180
181 av_freep(&asf->buf);
182
183 ffio_init_context(pb, buf, len, 0, NULL, NULL, NULL, NULL);
184
185 while (avio_tell(pb) + 4 < len) {
186 int start_off = avio_tell(pb);
187
188 mflags = avio_r8(pb);
189 if (mflags & 0x80)
190 flags |= RTP_FLAG_KEY;
191 len_off = avio_rb24(pb);
192 if (mflags & 0x20) /**< relative timestamp */
193 avio_skip(pb, 4);
194 if (mflags & 0x10) /**< has duration */
195 avio_skip(pb, 4);
196 if (mflags & 0x8) /**< has location ID */
197 avio_skip(pb, 4);
198 off = avio_tell(pb);
199
200 if (!(mflags & 0x40)) {
201 /**
202 * If 0x40 is not set, the len_off field specifies an offset
203 * of this packet's payload data in the complete (reassembled)
204 * ASF packet. This is used to spread one ASF packet over
205 * multiple RTP packets.
206 */
207 if (asf->pktbuf && len_off != avio_tell(asf->pktbuf)) {
208 uint8_t *p;
209 avio_close_dyn_buf(asf->pktbuf, &p);
210 asf->pktbuf = NULL;
211 av_free(p);
212 }
213 if (!len_off && !asf->pktbuf &&
214 (res = avio_open_dyn_buf(&asf->pktbuf)) < 0)
215 return res;
216 if (!asf->pktbuf)
217 return AVERROR(EIO);
218
219 avio_write(asf->pktbuf, buf + off, len - off);
220 avio_skip(pb, len - off);
221 if (!(flags & RTP_FLAG_MARKER))
222 return -1;
223 out_len = avio_close_dyn_buf(asf->pktbuf, &asf->buf);
224 asf->pktbuf = NULL;
225 } else {
226 /**
227 * If 0x40 is set, the len_off field specifies the length of
228 * the next ASF packet that can be read from this payload
229 * data alone. This is commonly the same as the payload size,
230 * but could be less in case of packet splitting (i.e.
231 * multiple ASF packets in one RTP packet).
232 */
233
234 int cur_len = start_off + len_off - off;
235 int prev_len = out_len;
236 void *newmem;
237 out_len += cur_len;
238 if (FFMIN(cur_len, len - off) < 0)
239 return -1;
240 newmem = av_realloc(asf->buf, out_len);
241 if (!newmem)
242 return -1;
243 asf->buf = newmem;
244 memcpy(asf->buf + prev_len, buf + off,
245 FFMIN(cur_len, len - off));
246 avio_skip(pb, cur_len);
247 }
248 }
249
250 init_packetizer(pb, asf->buf, out_len);
251 pb->pos += rt->asf_pb_pos;
252 pb->eof_reached = 0;
253 rt->asf_ctx->pb = pb;
254 }
255
256 for (;;) {
257 int i;
258
259 res = ff_read_packet(rt->asf_ctx, pkt);
260 rt->asf_pb_pos = avio_tell(pb);
261 if (res != 0)
262 break;
263 for (i = 0; i < s->nb_streams; i++) {
264 if (s->streams[i]->id == rt->asf_ctx->streams[pkt->stream_index]->id) {
265 pkt->stream_index = i;
266 return 1; // FIXME: return 0 if last packet
267 }
268 }
269 av_free_packet(pkt);
270 }
271
272 return res == 1 ? -1 : res;
273 }
274
275 static PayloadContext *asfrtp_new_context(void)
276 {
277 return av_mallocz(sizeof(PayloadContext));
278 }
279
280 static void asfrtp_free_context(PayloadContext *asf)
281 {
282 if (asf->pktbuf) {
283 uint8_t *p = NULL;
284 avio_close_dyn_buf(asf->pktbuf, &p);
285 asf->pktbuf = NULL;
286 av_free(p);
287 }
288 av_freep(&asf->buf);
289 av_free(asf);
290 }
291
292 #define RTP_ASF_HANDLER(n, s, t) \
293 RTPDynamicProtocolHandler ff_ms_rtp_ ## n ## _handler = { \
294 .enc_name = s, \
295 .codec_type = t, \
296 .codec_id = CODEC_ID_NONE, \
297 .parse_sdp_a_line = asfrtp_parse_sdp_line, \
298 .alloc = asfrtp_new_context, \
299 .free = asfrtp_free_context, \
300 .parse_packet = asfrtp_parse_packet, \
301 }
302
303 RTP_ASF_HANDLER(asf_pfv, "x-asf-pf", AVMEDIA_TYPE_VIDEO);
304 RTP_ASF_HANDLER(asf_pfa, "x-asf-pf", AVMEDIA_TYPE_AUDIO);