blob: a082b45f9817c5c03ba52e905200194fde43e658
1 | /* |
2 | * RTMP packet utilities |
3 | * Copyright (c) 2009 Konstantin Shishkov |
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 | #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_field; ///< 24-bit timestamp or increment to the previous one, in milliseconds (latter only for media packets). Clipped to a maximum of 0xFFFFFF, indicating an extended timestamp field. |
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 | * @param nb_prev_pkt number of allocated elements in prev_pkt |
118 | * @return number of bytes read on success, negative value otherwise |
119 | */ |
120 | int ff_rtmp_packet_read(URLContext *h, RTMPPacket *p, |
121 | int chunk_size, RTMPPacket **prev_pkt, |
122 | int *nb_prev_pkt); |
123 | /** |
124 | * Read internal RTMP packet sent by the server. |
125 | * |
126 | * @param h reader context |
127 | * @param p packet |
128 | * @param chunk_size current chunk size |
129 | * @param prev_pkt previously read packet headers for all channels |
130 | * (may be needed for restoring incomplete packet header) |
131 | * @param nb_prev_pkt number of allocated elements in prev_pkt |
132 | * @param c the first byte already read |
133 | * @return number of bytes read on success, negative value otherwise |
134 | */ |
135 | int ff_rtmp_packet_read_internal(URLContext *h, RTMPPacket *p, int chunk_size, |
136 | RTMPPacket **prev_pkt, int *nb_prev_pkt, |
137 | uint8_t c); |
138 | |
139 | /** |
140 | * Send RTMP packet to the server. |
141 | * |
142 | * @param h reader context |
143 | * @param p packet to send |
144 | * @param chunk_size current chunk size |
145 | * @param prev_pkt previously sent packet headers for all channels |
146 | * (may be used for packet header compressing) |
147 | * @param nb_prev_pkt number of allocated elements in prev_pkt |
148 | * @return number of bytes written on success, negative value otherwise |
149 | */ |
150 | int ff_rtmp_packet_write(URLContext *h, RTMPPacket *p, |
151 | int chunk_size, RTMPPacket **prev_pkt, |
152 | int *nb_prev_pkt); |
153 | |
154 | /** |
155 | * Print information and contents of RTMP packet. |
156 | * |
157 | * @param ctx output context |
158 | * @param p packet to dump |
159 | */ |
160 | void ff_rtmp_packet_dump(void *ctx, RTMPPacket *p); |
161 | |
162 | /** |
163 | * Enlarge the prev_pkt array to fit the given channel |
164 | * |
165 | * @param prev_pkt array with previously sent packet headers |
166 | * @param nb_prev_pkt number of allocated elements in prev_pkt |
167 | * @param channel the channel number that needs to be allocated |
168 | */ |
169 | int ff_rtmp_check_alloc_array(RTMPPacket **prev_pkt, int *nb_prev_pkt, |
170 | int channel); |
171 | |
172 | /** |
173 | * @name Functions used to work with the AMF format (which is also used in .flv) |
174 | * @see amf_* funcs in libavformat/flvdec.c |
175 | * @{ |
176 | */ |
177 | |
178 | /** |
179 | * Calculate number of bytes taken by first AMF entry in data. |
180 | * |
181 | * @param data input data |
182 | * @param data_end input buffer end |
183 | * @return number of bytes used by first AMF entry |
184 | */ |
185 | int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end); |
186 | |
187 | /** |
188 | * Retrieve value of given AMF object field in string form. |
189 | * |
190 | * @param data AMF object data |
191 | * @param data_end input buffer end |
192 | * @param name name of field to retrieve |
193 | * @param dst buffer for storing result |
194 | * @param dst_size output buffer size |
195 | * @return 0 if search and retrieval succeeded, negative value otherwise |
196 | */ |
197 | int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end, |
198 | const uint8_t *name, uint8_t *dst, int dst_size); |
199 | |
200 | /** |
201 | * Write boolean value in AMF format to buffer. |
202 | * |
203 | * @param dst pointer to the input buffer (will be modified) |
204 | * @param val value to write |
205 | */ |
206 | void ff_amf_write_bool(uint8_t **dst, int val); |
207 | |
208 | /** |
209 | * Write number in AMF format to buffer. |
210 | * |
211 | * @param dst pointer to the input buffer (will be modified) |
212 | * @param num value to write |
213 | */ |
214 | void ff_amf_write_number(uint8_t **dst, double num); |
215 | |
216 | /** |
217 | * Write string in AMF format to buffer. |
218 | * |
219 | * @param dst pointer to the input buffer (will be modified) |
220 | * @param str string to write |
221 | */ |
222 | void ff_amf_write_string(uint8_t **dst, const char *str); |
223 | |
224 | /** |
225 | * Write a string consisting of two parts in AMF format to a buffer. |
226 | * |
227 | * @param dst pointer to the input buffer (will be modified) |
228 | * @param str1 first string to write, may be null |
229 | * @param str2 second string to write, may be null |
230 | */ |
231 | void ff_amf_write_string2(uint8_t **dst, const char *str1, const char *str2); |
232 | |
233 | /** |
234 | * Write AMF NULL value to buffer. |
235 | * |
236 | * @param dst pointer to the input buffer (will be modified) |
237 | */ |
238 | void ff_amf_write_null(uint8_t **dst); |
239 | |
240 | /** |
241 | * Write marker for AMF object to buffer. |
242 | * |
243 | * @param dst pointer to the input buffer (will be modified) |
244 | */ |
245 | void ff_amf_write_object_start(uint8_t **dst); |
246 | |
247 | /** |
248 | * Write string used as field name in AMF object to buffer. |
249 | * |
250 | * @param dst pointer to the input buffer (will be modified) |
251 | * @param str string to write |
252 | */ |
253 | void ff_amf_write_field_name(uint8_t **dst, const char *str); |
254 | |
255 | /** |
256 | * Write marker for end of AMF object to buffer. |
257 | * |
258 | * @param dst pointer to the input buffer (will be modified) |
259 | */ |
260 | void ff_amf_write_object_end(uint8_t **dst); |
261 | |
262 | /** |
263 | * Read AMF boolean value. |
264 | * |
265 | *@param[in,out] gbc GetByteContext initialized with AMF-formatted data |
266 | *@param[out] val 0 or 1 |
267 | *@return 0 on success or an AVERROR code on failure |
268 | */ |
269 | int ff_amf_read_bool(GetByteContext *gbc, int *val); |
270 | |
271 | /** |
272 | * Read AMF number value. |
273 | * |
274 | *@param[in,out] gbc GetByteContext initialized with AMF-formatted data |
275 | *@param[out] val read value |
276 | *@return 0 on success or an AVERROR code on failure |
277 | */ |
278 | int ff_amf_read_number(GetByteContext *gbc, double *val); |
279 | |
280 | /** |
281 | * Get AMF string value. |
282 | * |
283 | * This function behaves the same as ff_amf_read_string except that |
284 | * it does not expect the AMF type prepended to the actual data. |
285 | * Appends a trailing null byte to output string in order to |
286 | * ease later parsing. |
287 | * |
288 | *@param[in,out] gbc GetByteContext initialized with AMF-formatted data |
289 | *@param[out] str read string |
290 | *@param[in] strsize buffer size available to store the read string |
291 | *@param[out] length read string length |
292 | *@return 0 on success or an AVERROR code on failure |
293 | */ |
294 | int ff_amf_get_string(GetByteContext *bc, uint8_t *str, |
295 | int strsize, int *length); |
296 | |
297 | /** |
298 | * Read AMF string value. |
299 | * |
300 | * Appends a trailing null byte to output string in order to |
301 | * ease later parsing. |
302 | * |
303 | *@param[in,out] gbc GetByteContext initialized with AMF-formatted data |
304 | *@param[out] str read string |
305 | *@param[in] strsize buffer size available to store the read string |
306 | *@param[out] length read string length |
307 | *@return 0 on success or an AVERROR code on failure |
308 | */ |
309 | int ff_amf_read_string(GetByteContext *gbc, uint8_t *str, |
310 | int strsize, int *length); |
311 | |
312 | /** |
313 | * Read AMF NULL value. |
314 | * |
315 | *@param[in,out] gbc GetByteContext initialized with AMF-formatted data |
316 | *@return 0 on success or an AVERROR code on failure |
317 | */ |
318 | int ff_amf_read_null(GetByteContext *gbc); |
319 | |
320 | /** |
321 | * Match AMF string with a NULL-terminated string. |
322 | * |
323 | * @return 0 if the strings do not match. |
324 | */ |
325 | |
326 | int ff_amf_match_string(const uint8_t *data, int size, const char *str); |
327 | |
328 | /** @} */ // AMF funcs |
329 | |
330 | #endif /* AVFORMAT_RTMPPKT_H */ |
331 |