RTMP protocol support (as a client)

Originally committed as revision 19556 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 212 insertions, 0 deletions

diff --git a/libavformat/rtmppkt.h b/libavformat/rtmppkt.h
new file mode 100644
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--- /dev/null
+++ b/libavformat/rtmppkt.h
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+/*
+ * RTMP packet utilities
+ * Copyright (c) 2009 Kostya Shishkov
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVFORMAT_RTMPPKT_H
+#define AVFORMAT_RTMPPKT_H
+
+#include "avformat.h"
+
+/** maximum possible number of different RTMP channels */
+#define RTMP_CHANNELS 64
+
+/**
+ * channels used to for RTMP packets with different purposes (i.e. data, network
+ * control, remote procedure calls, etc.)
+ */
+enum RTMPChannel {
+    RTMP_NETWORK_CHANNEL = 2,   ///< channel for network-related messages (bandwidth report, ping, etc)
+    RTMP_SYSTEM_CHANNEL,        ///< channel for sending server control messages
+    RTMP_VIDEO_CHANNEL = 8,     ///< channel for video data
+    RTMP_AUDIO_CHANNEL,         ///< channel for audio data
+};
+
+/**
+ * known RTMP packet types
+ */
+typedef enum RTMPPacketType {
+    RTMP_PT_CHUNK_SIZE   =  1,  ///< chunk size change
+    RTMP_PT_BYTES_READ   =  3,  ///< number of bytes read
+    RTMP_PT_PING,               ///< ping
+    RTMP_PT_SERVER_BW,          ///< server bandwidth
+    RTMP_PT_CLIENT_BW,          ///< client bandwidth
+    RTMP_PT_AUDIO        =  8,  ///< audio packet
+    RTMP_PT_VIDEO,              ///< video packet
+    RTMP_PT_FLEX_STREAM  = 15,  ///< Flex shared stream
+    RTMP_PT_FLEX_OBJECT,        ///< Flex shared object
+    RTMP_PT_FLEX_MESSAGE,       ///< Flex shared message
+    RTMP_PT_NOTIFY,             ///< some notification
+    RTMP_PT_SHARED_OBJ,         ///< shared object
+    RTMP_PT_INVOKE,             ///< invoke some stream action
+    RTMP_PT_METADATA     = 22,  ///< FLV metadata
+} RTMPPacketType;
+
+/**
+ * possible RTMP packet header sizes
+ */
+enum RTMPPacketSize {
+    RTMP_PS_TWELVEBYTES = 0, ///< packet has 12-byte header
+    RTMP_PS_EIGHTBYTES,      ///< packet has 8-byte header
+    RTMP_PS_FOURBYTES,       ///< packet has 4-byte header
+    RTMP_PS_ONEBYTE          ///< packet is really a next chunk of a packet
+};
+
+/**
+ * structure for holding RTMP packets
+ */
+typedef struct RTMPPacket {
+    uint8_t        channel_id; ///< RTMP channel ID (nothing to do with audio/video channels though)
+    RTMPPacketType type;       ///< packet payload type
+    uint32_t       timestamp;  ///< packet full timestamp or timestamp increment to the previous one in milliseconds (latter only for media packets)
+    uint32_t       extra;      ///< probably an additional channel ID used during streaming data
+    uint8_t        *data;      ///< packet payload
+    int            data_size;  ///< packet payload size
+} RTMPPacket;
+
+/**
+ * Creates new RTMP packet with given attributes.
+ *
+ * @param pkt        packet
+ * @param channel_id packet channel ID
+ * @param type       packet type
+ * @param timestamp  packet timestamp
+ * @param size       packet size
+ * @return zero on success, negative value otherwise
+ */
+int ff_rtmp_packet_create(RTMPPacket *pkt, int channel_id, RTMPPacketType type,
+                          int timestamp, int size);
+
+/**
+ * Frees RTMP packet.
+ *
+ * @param pkt packet
+ */
+void ff_rtmp_packet_destroy(RTMPPacket *pkt);
+
+/**
+ * Reads RTMP packet sent by the server.
+ *
+ * @param h          reader context
+ * @param p          packet
+ * @param chunk_size current chunk size
+ * @param prev_pkt   previously read packet headers for all channels
+ *                   (may be needed for restoring incomplete packet header)
+ * @return zero on success, negative value otherwise
+ */
+int ff_rtmp_packet_read(URLContext *h, RTMPPacket *p,
+                        int chunk_size, RTMPPacket *prev_pkt);
+
+/**
+ * Sends RTMP packet to the server.
+ *
+ * @param h          reader context
+ * @param p          packet to send
+ * @param chunk_size current chunk size
+ * @param prev_pkt   previously sent packet headers for all channels
+ *                   (may be used for packet header compressing)
+ * @return zero on success, negative value otherwise
+ */
+int ff_rtmp_packet_write(URLContext *h, RTMPPacket *p,
+                         int chunk_size, RTMPPacket *prev_pkt);
+
+/**
+ * @defgroup amffuncs functions used to work with AMF format (which is also used in .flv)
+ * @see amf_* funcs in libavformat/flvdec.c
+ * @{
+ */
+
+/**
+ * Calculates number of bytes taken by first AMF entry in data.
+ *
+ * @param data input data
+ * @param data_end input buffer end
+ * @return number of bytes used by first AMF entry
+ */
+int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end);
+
+/**
+ * Retrieves value of given AMF object field in string form.
+ *
+ * @param data     AMF object data
+ * @param data_end input buffer end
+ * @param name     name of field to retrieve
+ * @param dst      buffer for storing result
+ * @param dst_size output buffer size
+ * @return 0 if search and retrieval succeeded, negative value otherwise
+ */
+int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
+                           const uint8_t *name, uint8_t *dst, int dst_size);
+
+/**
+ * Writes boolean value in AMF format to buffer.
+ *
+ * @param dst pointer to the input buffer (will be modified)
+ * @param val value to write
+ */
+void ff_amf_write_bool(uint8_t **dst, int val);
+
+/**
+ * Writes number in AMF format to buffer.
+ *
+ * @param dst pointer to the input buffer (will be modified)
+ * @param num value to write
+ */
+void ff_amf_write_number(uint8_t **dst, double num);
+
+/**
+ * Writes string in AMF format to buffer.
+ *
+ * @param dst pointer to the input buffer (will be modified)
+ * @param str string to write
+ */
+void ff_amf_write_string(uint8_t **dst, const char *str);
+
+/**
+ * Writes AMF NULL value to buffer.
+ *
+ * @param dst pointer to the input buffer (will be modified)
+ */
+void ff_amf_write_null(uint8_t **dst);
+
+/**
+ * Writes marker for AMF object to buffer.
+ *
+ * @param dst pointer to the input buffer (will be modified)
+ */
+void ff_amf_write_object_start(uint8_t **dst);
+
+/**
+ * Writes string used as field name in AMF object to buffer.
+ *
+ * @param dst pointer to the input buffer (will be modified)
+ * @param str string to write
+ */
+void ff_amf_write_field_name(uint8_t **dst, const char *str);
+
+/**
+ * Writes marker for end of AMF object to buffer.
+ *
+ * @param dst pointer to the input buffer (will be modified)
+ */
+void ff_amf_write_object_end(uint8_t **dst);
+
+/** @} */ // AMF funcs
+
+#endif /* AVFORMAT_RTMPPKT_H */