| 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 */ |