rtmp: Support reading interleaved chunks.
[libav.git] / libavformat / rtmppkt.h
1 /*
2 * RTMP packet utilities
3 * Copyright (c) 2009 Konstantin Shishkov
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 #ifndef AVFORMAT_RTMPPKT_H
23 #define AVFORMAT_RTMPPKT_H
24
25 #include "libavcodec/bytestream.h"
26 #include "avformat.h"
27 #include "url.h"
28
29 /** maximum possible number of different RTMP channels */
30 #define RTMP_CHANNELS 65599
31
32 /**
33 * channels used to for RTMP packets with different purposes (i.e. data, network
34 * control, remote procedure calls, etc.)
35 */
36 enum RTMPChannel {
37 RTMP_NETWORK_CHANNEL = 2, ///< channel for network-related messages (bandwidth report, ping, etc)
38 RTMP_SYSTEM_CHANNEL, ///< channel for sending server control messages
39 RTMP_AUDIO_CHANNEL, ///< channel for audio data
40 RTMP_VIDEO_CHANNEL = 6, ///< channel for video data
41 RTMP_SOURCE_CHANNEL = 8, ///< channel for a/v invokes
42 };
43
44 /**
45 * known RTMP packet types
46 */
47 typedef enum RTMPPacketType {
48 RTMP_PT_CHUNK_SIZE = 1, ///< chunk size change
49 RTMP_PT_BYTES_READ = 3, ///< number of bytes read
50 RTMP_PT_PING, ///< ping
51 RTMP_PT_SERVER_BW, ///< server bandwidth
52 RTMP_PT_CLIENT_BW, ///< client bandwidth
53 RTMP_PT_AUDIO = 8, ///< audio packet
54 RTMP_PT_VIDEO, ///< video packet
55 RTMP_PT_FLEX_STREAM = 15, ///< Flex shared stream
56 RTMP_PT_FLEX_OBJECT, ///< Flex shared object
57 RTMP_PT_FLEX_MESSAGE, ///< Flex shared message
58 RTMP_PT_NOTIFY, ///< some notification
59 RTMP_PT_SHARED_OBJ, ///< shared object
60 RTMP_PT_INVOKE, ///< invoke some stream action
61 RTMP_PT_METADATA = 22, ///< FLV metadata
62 } RTMPPacketType;
63
64 /**
65 * possible RTMP packet header sizes
66 */
67 enum RTMPPacketSize {
68 RTMP_PS_TWELVEBYTES = 0, ///< packet has 12-byte header
69 RTMP_PS_EIGHTBYTES, ///< packet has 8-byte header
70 RTMP_PS_FOURBYTES, ///< packet has 4-byte header
71 RTMP_PS_ONEBYTE ///< packet is really a next chunk of a packet
72 };
73
74 /**
75 * structure for holding RTMP packets
76 */
77 typedef struct RTMPPacket {
78 int channel_id; ///< RTMP channel ID (nothing to do with audio/video channels though)
79 RTMPPacketType type; ///< packet payload type
80 uint32_t timestamp; ///< packet full timestamp
81 uint32_t ts_delta; ///< timestamp increment to the previous one in milliseconds (latter only for media packets)
82 uint32_t extra; ///< probably an additional channel ID used during streaming data
83 uint8_t *data; ///< packet payload
84 int size; ///< packet payload size
85 int offset; ///< amount of data read so far
86 int read; ///< amount read, including headers
87 } RTMPPacket;
88
89 /**
90 * Create new RTMP packet with given attributes.
91 *
92 * @param pkt packet
93 * @param channel_id packet channel ID
94 * @param type packet type
95 * @param timestamp packet timestamp
96 * @param size packet size
97 * @return zero on success, negative value otherwise
98 */
99 int ff_rtmp_packet_create(RTMPPacket *pkt, int channel_id, RTMPPacketType type,
100 int timestamp, int size);
101
102 /**
103 * Free RTMP packet.
104 *
105 * @param pkt packet
106 */
107 void ff_rtmp_packet_destroy(RTMPPacket *pkt);
108
109 /**
110 * Read RTMP packet sent by the server.
111 *
112 * @param h reader context
113 * @param p packet
114 * @param chunk_size current chunk size
115 * @param prev_pkt previously read packet headers for all channels
116 * (may be needed for restoring incomplete packet header)
117 * @return number of bytes read on success, negative value otherwise
118 */
119 int ff_rtmp_packet_read(URLContext *h, RTMPPacket *p,
120 int chunk_size, RTMPPacket *prev_pkt);
121 /**
122 * Read internal RTMP packet sent by the server.
123 *
124 * @param h reader context
125 * @param p packet
126 * @param chunk_size current chunk size
127 * @param prev_pkt previously read packet headers for all channels
128 * (may be needed for restoring incomplete packet header)
129 * @param c the first byte already read
130 * @return number of bytes read on success, negative value otherwise
131 */
132 int ff_rtmp_packet_read_internal(URLContext *h, RTMPPacket *p, int chunk_size,
133 RTMPPacket *prev_pkt, uint8_t c);
134
135 /**
136 * Send RTMP packet to the server.
137 *
138 * @param h reader context
139 * @param p packet to send
140 * @param chunk_size current chunk size
141 * @param prev_pkt previously sent packet headers for all channels
142 * (may be used for packet header compressing)
143 * @return number of bytes written on success, negative value otherwise
144 */
145 int ff_rtmp_packet_write(URLContext *h, RTMPPacket *p,
146 int chunk_size, RTMPPacket *prev_pkt);
147
148 /**
149 * Print information and contents of RTMP packet.
150 *
151 * @param ctx output context
152 * @param p packet to dump
153 */
154 void ff_rtmp_packet_dump(void *ctx, RTMPPacket *p);
155
156 /**
157 * @name Functions used to work with the AMF format (which is also used in .flv)
158 * @see amf_* funcs in libavformat/flvdec.c
159 * @{
160 */
161
162 /**
163 * Calculate number of bytes taken by first AMF entry in data.
164 *
165 * @param data input data
166 * @param data_end input buffer end
167 * @return number of bytes used by first AMF entry
168 */
169 int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end);
170
171 /**
172 * Retrieve value of given AMF object field in string form.
173 *
174 * @param data AMF object data
175 * @param data_end input buffer end
176 * @param name name of field to retrieve
177 * @param dst buffer for storing result
178 * @param dst_size output buffer size
179 * @return 0 if search and retrieval succeeded, negative value otherwise
180 */
181 int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
182 const uint8_t *name, uint8_t *dst, int dst_size);
183
184 /**
185 * Write boolean value in AMF format to buffer.
186 *
187 * @param dst pointer to the input buffer (will be modified)
188 * @param val value to write
189 */
190 void ff_amf_write_bool(uint8_t **dst, int val);
191
192 /**
193 * Write number in AMF format to buffer.
194 *
195 * @param dst pointer to the input buffer (will be modified)
196 * @param num value to write
197 */
198 void ff_amf_write_number(uint8_t **dst, double num);
199
200 /**
201 * Write string in AMF format to buffer.
202 *
203 * @param dst pointer to the input buffer (will be modified)
204 * @param str string to write
205 */
206 void ff_amf_write_string(uint8_t **dst, const char *str);
207
208 /**
209 * Write a string consisting of two parts in AMF format to a buffer.
210 *
211 * @param dst pointer to the input buffer (will be modified)
212 * @param str1 first string to write, may be null
213 * @param str2 second string to write, may be null
214 */
215 void ff_amf_write_string2(uint8_t **dst, const char *str1, const char *str2);
216
217 /**
218 * Write AMF NULL value to buffer.
219 *
220 * @param dst pointer to the input buffer (will be modified)
221 */
222 void ff_amf_write_null(uint8_t **dst);
223
224 /**
225 * Write marker for AMF object to buffer.
226 *
227 * @param dst pointer to the input buffer (will be modified)
228 */
229 void ff_amf_write_object_start(uint8_t **dst);
230
231 /**
232 * Write string used as field name in AMF object to buffer.
233 *
234 * @param dst pointer to the input buffer (will be modified)
235 * @param str string to write
236 */
237 void ff_amf_write_field_name(uint8_t **dst, const char *str);
238
239 /**
240 * Write marker for end of AMF object to buffer.
241 *
242 * @param dst pointer to the input buffer (will be modified)
243 */
244 void ff_amf_write_object_end(uint8_t **dst);
245
246 /**
247 * Read AMF boolean value.
248 *
249 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
250 *@param[out] val 0 or 1
251 *@return 0 on success or an AVERROR code on failure
252 */
253 int ff_amf_read_bool(GetByteContext *gbc, int *val);
254
255 /**
256 * Read AMF number value.
257 *
258 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
259 *@param[out] val read value
260 *@return 0 on success or an AVERROR code on failure
261 */
262 int ff_amf_read_number(GetByteContext *gbc, double *val);
263
264 /**
265 * Read AMF string value.
266 *
267 * Appends a trailing null byte to output string in order to
268 * ease later parsing.
269 *
270 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
271 *@param[out] str read string
272 *@param[in] strsize buffer size available to store the read string
273 *@param[out] length read string length
274 *@return 0 on success or an AVERROR code on failure
275 */
276 int ff_amf_read_string(GetByteContext *gbc, uint8_t *str,
277 int strsize, int *length);
278
279 /**
280 * Read AMF NULL value.
281 *
282 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
283 *@return 0 on success or an AVERROR code on failure
284 */
285 int ff_amf_read_null(GetByteContext *gbc);
286
287 /**
288 * Match AMF string with a NULL-terminated string.
289 *
290 * @return 0 if the strings do not match.
291 */
292
293 int ff_amf_match_string(const uint8_t *data, int size, const char *str);
294
295 /** @} */ // AMF funcs
296
297 #endif /* AVFORMAT_RTMPPKT_H */