ngx_rtmp.h

/*
 * Original work Copyright (C) Roman Arutyunyan
 * Modified work Copyright (C) 2017 Gnolizuh
 */


#ifndef _NGX_RTMP_H_INCLUDED_
#define _NGX_RTMP_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#include <ngx_event_connect.h>
#include <ngx_http.h>
#include <nginx.h>


typedef struct ngx_rtmp_session_s       ngx_rtmp_session_t;
typedef struct ngx_rtmp_conf_ctx_s      ngx_rtmp_conf_ctx_t;
typedef struct ngx_rtmp_core_svi_conf_s ngx_rtmp_core_svi_conf_t;

#include <ngx_rtmp_variables.h>
#include <ngx_rtmp_core_module.h>
#include "ngx_rtmp_amf.h"
#include "ngx_rtmp_bandwidth.h"


#if (NGX_WIN32)
typedef __int8              int8_t;
typedef unsigned __int8     uint8_t;
#endif


struct ngx_rtmp_conf_ctx_s {
    void                  **main_conf;
    void                  **srv_conf;
    void                  **svi_conf;
    void                  **app_conf;
};


typedef struct {
    union {
        struct sockaddr        sockaddr;
        struct sockaddr_in     sockaddr_in;
#if (NGX_HAVE_INET6)
        struct sockaddr_in6    sockaddr_in6;
#endif
#if (NGX_HAVE_UNIX_DOMAIN)
        struct sockaddr_un     sockaddr_un;
#endif
        u_char                 sockaddr_data[NGX_SOCKADDRLEN];
    } u;
    u_char                     sockaddr[NGX_SOCKADDRLEN];
    socklen_t                  socklen;

    /* server ctx */
    ngx_rtmp_conf_ctx_t       *ctx;

    unsigned                   set:1;
    unsigned                   default_server:1;
    unsigned                   bind:1;
    unsigned                   wildcard:1;
#if (NGX_HTTP_SSL)
    unsigned                   ssl:1;
#endif
#if (NGX_HTTP_V2)
    unsigned                   http2:1;
#endif
#if (NGX_HAVE_INET6 && defined IPV6_V6ONLY)
    unsigned                   ipv6only:1;
#endif

#if (NGX_HAVE_REUSEPORT)
    unsigned                   reuseport:1;
#endif
    unsigned                   so_keepalive:2;
    unsigned                   proxy_protocol:1;

    int                        backlog;
    int                        rcvbuf;
    int                        sndbuf;
#if (NGX_HAVE_SETFIB)
    int                        setfib;
#endif
#if (NGX_HAVE_TCP_FASTOPEN)
    int                        fastopen;
#endif
#if (NGX_HAVE_KEEPALIVE_TUNABLE)
    int                        tcp_keepidle;
    int                        tcp_keepintvl;
    int                        tcp_keepcnt;
#endif

#if (NGX_HAVE_DEFERRED_ACCEPT && defined SO_ACCEPTFILTER)
    char                      *accept_filter;
#endif
#if (NGX_HAVE_DEFERRED_ACCEPT && defined TCP_DEFER_ACCEPT)
    ngx_uint_t                 deferred_accept;
#endif

    u_char                     addr[NGX_SOCKADDR_STRLEN + 1];
} ngx_rtmp_listen_opt_t;


typedef struct {
    ngx_hash_combined_t        names;

    ngx_uint_t                 nregex;
    ngx_rtmp_host_name_t      *regex;
} ngx_rtmp_virtual_hosts_t;


typedef struct {
    ngx_rtmp_core_srv_conf_t  *default_server;

    ngx_rtmp_virtual_hosts_t  *virtual_hosts;

    ngx_rtmp_conf_ctx_t       *ctx;
    ngx_str_t                  addr_text;
    unsigned                   proxy_protocol:1;
} ngx_rtmp_addr_conf_t;


typedef struct {
    in_addr_t               addr;
    ngx_rtmp_addr_conf_t    conf;
} ngx_rtmp_in_addr_t;


#if (NGX_HAVE_INET6)

typedef struct {
    struct in6_addr         addr6;
    ngx_rtmp_addr_conf_t    conf;
} ngx_rtmp_in6_addr_t;

#endif


typedef struct {
    void                   *addrs;
    ngx_uint_t              naddrs;
} ngx_rtmp_port_t;


typedef struct {
    int                     family;
    in_port_t               port;
    ngx_array_t             ports;
    ngx_array_t             addrs;       /* array of ngx_rtmp_conf_addr_t */
} ngx_rtmp_conf_port_t;


typedef struct {
    ngx_rtmp_listen_opt_t     opt;

    ngx_hash_t                 hash;
    ngx_hash_wildcard_t       *wc_head;
    ngx_hash_wildcard_t       *wc_tail;

#if (NGX_PCRE)
    ngx_uint_t                 nregex;
    ngx_rtmp_host_name_t      *regex;
#endif

    struct sockaddr          *sockaddr;
    socklen_t                 socklen;

    ngx_rtmp_conf_ctx_t      *ctx;

    unsigned                  bind:1;
    unsigned                  wildcard:1;
#if (NGX_HAVE_INET6 && defined IPV6_V6ONLY)
    unsigned                  ipv6only:1;
#endif
    unsigned                  so_keepalive:2;
    unsigned                  proxy_protocol:1;

    /* the default server configuration for this address:port */
    ngx_rtmp_core_srv_conf_t *default_server;
    ngx_array_t               servers;         /* array of ngx_rtmp_core_srv_conf_t */
} ngx_rtmp_conf_addr_t;

#define NGX_RTMP_VERSION                3

#define NGX_LOG_DEBUG_RTMP              NGX_LOG_DEBUG_CORE

#define NGX_RTMP_DEFAULT_CHUNK_SIZE     128

#define NGX_NONE_RELAY                  0
#define NGX_CLUSTER_RELAY               1
#define NGX_REMOTE_RELAY                2
#define NGX_LOCAL_RELAY                 3
#define	NGX_ERROR_RELAY					4

#define NGX_PROTO_TYPE_UNKNOWN          0
#define NGX_PROTO_TYPE_RTMP             1
#define NGX_PROTO_TYPE_RTMP_PULL        2
#define NGX_PROTO_TYPE_RTMP_PUSH        3
#define NGX_PROTO_TYPE_HLS_TS_PULL      4
#define NGX_PROTO_TYPE_HLS_M3U8_PULL    5
#define NGX_PROTO_TYPE_HTTP_FLV_PULL    6


/* RTMP message types */
#define NGX_RTMP_MSG_CHUNK_SIZE         1
#define NGX_RTMP_MSG_ABORT              2
#define NGX_RTMP_MSG_ACK                3
#define NGX_RTMP_MSG_USER               4
#define NGX_RTMP_MSG_ACK_SIZE           5
#define NGX_RTMP_MSG_BANDWIDTH          6
#define NGX_RTMP_MSG_EDGE               7
#define NGX_RTMP_MSG_AUDIO              8
#define NGX_RTMP_MSG_VIDEO              9
#define NGX_RTMP_MSG_AMF3_META          15
#define NGX_RTMP_MSG_AMF3_SHARED        16
#define NGX_RTMP_MSG_AMF3_CMD           17
#define NGX_RTMP_MSG_AMF_META           18
#define NGX_RTMP_MSG_AMF_SHARED         19
#define NGX_RTMP_MSG_AMF_CMD            20
#define NGX_RTMP_MSG_AGGREGATE          22
#define NGX_RTMP_MSG_MAX                22

#define NGX_RTMP_CONNECT                NGX_RTMP_MSG_MAX + 1
#define NGX_RTMP_DISCONNECT             NGX_RTMP_MSG_MAX + 2
#define NGX_RTMP_HANDSHAKE_DONE         NGX_RTMP_MSG_MAX + 3
#define NGX_RTMP_CONNECT_END            NGX_RTMP_MSG_MAX + 4
#define NGX_RTMP_PLAY_END               NGX_RTMP_MSG_MAX + 5
#define NGX_RTMP_MAX_EVENT              NGX_RTMP_MSG_MAX + 7


/* RMTP control message types */
#define NGX_RTMP_USER_STREAM_BEGIN      0
#define NGX_RTMP_USER_STREAM_EOF        1
#define NGX_RTMP_USER_STREAM_DRY        2
#define NGX_RTMP_USER_SET_BUFLEN        3
#define NGX_RTMP_USER_RECORDED          4
#define NGX_RTMP_USER_PING_REQUEST      6
#define NGX_RTMP_USER_PING_RESPONSE     7
#define NGX_RTMP_USER_UNKNOWN           8
#define NGX_RTMP_USER_BUFFER_END        31


/* Chunk header:
 *   max 3  basic header
 * + max 11 message header
 * + max 4  extended header (timestamp) */
#define NGX_RTMP_MAX_CHUNK_HEADER       18

/* FLV tag header:
 *   max 1  type
 * + max 3  body length
 * + max 3  timestamp
 * + max 1  extend timestamp
 * + max 3  streamid
 * .....[body] */
#define NGX_RTMP_MAX_FLV_TAG_HEADER     11

#define NGX_RTMP_MAX_FLV_TAG_SIZE_HEADER 4

typedef struct {
    uint32_t                csid;       /* chunk stream id */
    uint32_t                timestamp;  /* timestamp (delta) */
    uint32_t                mlen;       /* message length */
    uint8_t                 type;       /* message type id */
    uint32_t                msid;       /* message stream id */
} ngx_rtmp_header_t;


typedef struct {
    ngx_rtmp_header_t       hdr;
    uint32_t                dtime;
    uint32_t                len;        /* current fragment length */
    uint8_t                 ext;
    ngx_chain_t            *in;
} ngx_rtmp_stream_t;


/* disable zero-sized array warning by msvc */

#if (NGX_WIN32)
#pragma warning(push)
#pragma warning(disable:4200)
#endif


struct ngx_rtmp_session_s {
    uint32_t                signature;  /* "RTMP" */ /* <-- FIXME wtf */

    ngx_event_t             close;

    void                  **ctx;
    void                  **main_conf;
    void                  **srv_conf;
    void                  **svi_conf;
    void                  **app_conf;

    ngx_rtmp_addr_conf_t   *addr_conf;
    ngx_str_t              *addr_text;
    int                     connected;

#if (nginx_version >= 1007005)
    ngx_queue_t             posted_dry_events;
#else
    ngx_event_t            *posted_dry_events;
#endif

    /* client buffer time in msec */
    uint32_t                buflen;
    uint32_t                ack_size;

    /* connection parameters */
    ngx_str_t               app;
    ngx_str_t               name;
    ngx_str_t               host;
    ngx_str_t               service;
    ngx_str_t               args;
    ngx_str_t               flashver;
    ngx_str_t               swf_url;
    ngx_str_t               tc_url;
    uint32_t                acodecs;
    uint32_t                vcodecs;
    ngx_str_t               page_url;

    /* handshake data */
    ngx_buf_t              *hs_buf;
    u_char                 *hs_digest;
    unsigned                hs_old:1;
    ngx_uint_t              hs_stage;

    /* connection timestamps */
    ngx_msec_t              epoch;
    ngx_msec_t              peer_epoch;
    ngx_msec_t              base_time;
    uint32_t                current_time;

    /* ping */
    ngx_event_t             ping_evt;
    unsigned                ping_active:1;
    unsigned                ping_reset:1;

    /* auto-relay? */
    unsigned                master_relay:1;
    unsigned                remote_relay:1;
    unsigned                local_relay:1;
    unsigned                local_static_relay:1;

    ngx_uint_t              proto;
    ngx_uint_t              host_mask;
    ngx_pool_t             *pool;

    /* input stream 0 (reserved by RTMP spec)
     * is used as free chain link */

    ngx_rtmp_stream_t      *in_streams;
    uint32_t                in_csid;
    ngx_uint_t              in_chunk_size;
    ngx_pool_t             *in_pool;
    uint32_t                in_bytes;
    uint32_t                in_last_ack;

    ngx_pool_t             *in_old_pool;
    ngx_int_t               in_chunk_size_changing;

    ngx_connection_t       *connection;

    /* circular buffer of RTMP message pointers */
    ngx_msec_t              timeout;
    uint32_t                out_bytes;
    size_t                  out_pos, out_last;
    ngx_chain_t            *out_chain;
    u_char                 *out_bpos;
    unsigned                out_buffer:1;
    size_t                  out_queue;
    size_t                  out_cork;
    ngx_chain_t            *out[0];
};


#if (NGX_WIN32)
#pragma warning(pop)
#endif


/* handler result code:
 *  NGX_ERROR - error
 *  NGX_OK    - success, may continue
 *  NGX_DONE  - success, input parsed, reply sent; need no
 *      more calls on this event */
typedef ngx_int_t (*ngx_rtmp_handler_pt)(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h, ngx_chain_t *in);


typedef struct {
    ngx_str_t               name;
    ngx_rtmp_handler_pt     handler;
} ngx_rtmp_amf_handler_t;


typedef struct {
    ngx_array_t                servers;    /* ngx_rtmp_core_srv_conf_t */
    ngx_array_t                listen;     /* ngx_rtmp_listen_opt_t */

    ngx_array_t                events[NGX_RTMP_MAX_EVENT];

    ngx_hash_t                 amf_hash;
    ngx_array_t                amf_arrays;
    ngx_array_t                amf;
	ngx_array_t               *ports;

    ngx_array_t                variables;   /* ngx_rtmp_variable_t */
	ngx_uint_t                 ncaptures;

	ngx_uint_t                 host_names_hash_max_size;
    ngx_uint_t                 host_names_hash_bucket_size;

    ngx_hash_keys_arrays_t    *variables_keys;
} ngx_rtmp_core_main_conf_t;


/* global main conf for stats */
extern ngx_rtmp_core_main_conf_t   *ngx_rtmp_core_main_conf;


struct ngx_rtmp_core_svi_conf_s {
    /* array of the ngx_rtmp_host_name_t, "server_name" directive */
    ngx_array_t             host_names;

    ngx_array_t             applications; /* ngx_rtmp_core_app_conf_t */
    ngx_str_t               name;
    void                  **svi_conf;

    ngx_rtmp_conf_ctx_t    *ctx;

#if (NGX_PCRE)
    unsigned                captures:1;
#endif
};


typedef struct {
    ngx_array_t             applications; /* ngx_rtmp_core_app_conf_t */
    ngx_str_t               name;
    void                  **app_conf;
} ngx_rtmp_core_app_conf_t;


typedef struct {
    ngx_str_t              *client;
    ngx_rtmp_session_t     *session;
} ngx_rtmp_error_log_ctx_t;


typedef struct {
    ngx_int_t             (*preconfiguration)(ngx_conf_t *cf);
    ngx_int_t             (*postconfiguration)(ngx_conf_t *cf);

    void                 *(*create_main_conf)(ngx_conf_t *cf);
    char                 *(*init_main_conf)(ngx_conf_t *cf, void *conf);

    void                 *(*create_srv_conf)(ngx_conf_t *cf);
    char                 *(*merge_srv_conf)(ngx_conf_t *cf, void *prev,
                                    void *conf);

    void                 *(*create_svi_conf)(ngx_conf_t *cf);
    char                 *(*merge_svi_conf)(ngx_conf_t *cf, void *prev,
                                    void *conf);

    void                 *(*create_app_conf)(ngx_conf_t *cf);
    char                 *(*merge_app_conf)(ngx_conf_t *cf, void *prev,
                                    void *conf);
} ngx_rtmp_module_t;

#define NGX_RTMP_MODULE                 0x504D5452     /* "RTMP" */

#define NGX_RTMP_MAIN_CONF              0x02000000
#define NGX_RTMP_SRV_CONF               0x04000000
#define NGX_RTMP_SVI_CONF               0x08000000
#define NGX_RTMP_APP_CONF               0x10000000
#define NGX_RTMP_REC_CONF               0x20000000


#define NGX_RTMP_MAIN_CONF_OFFSET  offsetof(ngx_rtmp_conf_ctx_t, main_conf)
#define NGX_RTMP_SRV_CONF_OFFSET   offsetof(ngx_rtmp_conf_ctx_t, srv_conf)
#define NGX_RTMP_SVI_CONF_OFFSET   offsetof(ngx_rtmp_conf_ctx_t, svi_conf)
#define NGX_RTMP_APP_CONF_OFFSET   offsetof(ngx_rtmp_conf_ctx_t, app_conf)


#define ngx_rtmp_get_module_ctx(s, module)     (s)->ctx[module.ctx_index]
#define ngx_rtmp_set_ctx(s, c, module)         s->ctx[module.ctx_index] = c;
#define ngx_rtmp_delete_ctx(s, module)         s->ctx[module.ctx_index] = NULL;


#define ngx_rtmp_get_module_main_conf(s, module)                             \
    (s)->main_conf[module.ctx_index]
#define ngx_rtmp_get_module_srv_conf(s, module)  (s)->srv_conf[module.ctx_index]
#define ngx_rtmp_get_module_svi_conf(s, module)  ((s)->svi_conf ? \
    (s)->svi_conf[module.ctx_index] : NULL)
#define ngx_rtmp_get_module_app_conf(s, module)  ((s)->app_conf ? \
    (s)->app_conf[module.ctx_index] : NULL)

#define ngx_rtmp_conf_get_module_main_conf(cf, module)                       \
    ((ngx_rtmp_conf_ctx_t *) cf->ctx)->main_conf[module.ctx_index]
#define ngx_rtmp_conf_get_module_srv_conf(cf, module)                        \
    ((ngx_rtmp_conf_ctx_t *) cf->ctx)->srv_conf[module.ctx_index]
#define ngx_rtmp_conf_get_module_svi_conf(cf, module)                        \
    ((ngx_rtmp_conf_ctx_t *) cf->ctx)->svi_conf[module.ctx_index]
#define ngx_rtmp_conf_get_module_app_conf(cf, module)                        \
    ((ngx_rtmp_conf_ctx_t *) cf->ctx)->app_conf[module.ctx_index]


#ifdef NGX_DEBUG
char* ngx_rtmp_message_type(uint8_t type);
char* ngx_rtmp_user_message_type(uint16_t evt);
#endif

ngx_int_t ngx_rtmp_parse_tcurl(ngx_str_t tcurl, ngx_str_t *host, ngx_uint_t *host_mask);

ngx_int_t ngx_rtmp_add_listen(ngx_conf_t *cf, ngx_rtmp_core_srv_conf_t *cscf,
     ngx_rtmp_listen_opt_t *lsopt);

void ngx_rtmp_init_connection(ngx_connection_t *c);
ngx_rtmp_session_t * ngx_rtmp_init_session(ngx_connection_t *c,
     ngx_rtmp_addr_conf_t *addr_conf);

void ngx_http_flv_init_connection(ngx_http_request_t *r);
ngx_rtmp_session_t * ngx_http_flv_init_session(ngx_http_request_t *r,
     ngx_rtmp_addr_conf_t *addr_conf);
void ngx_http_flv_send(ngx_event_t *wev);
void ngx_http_flv_recv(ngx_event_t *rev);

void ngx_rtmp_finalize_session(ngx_rtmp_session_t *s);
void ngx_rtmp_handshake(ngx_rtmp_session_t *s);
void ngx_rtmp_client_handshake(ngx_rtmp_session_t *s, unsigned async);
void ngx_rtmp_free_handshake_buffers(ngx_rtmp_session_t *s);
void ngx_rtmp_cycle(ngx_rtmp_session_t *s);
void ngx_rtmp_reset_ping(ngx_rtmp_session_t *s);
ngx_int_t ngx_rtmp_fire_event(ngx_rtmp_session_t *s, ngx_uint_t evt,
        ngx_rtmp_header_t *h, ngx_chain_t *in);


ngx_int_t ngx_rtmp_set_chunk_size(ngx_rtmp_session_t *s, ngx_uint_t size);


/* Bit reverse: we need big-endians in many places  */
void * ngx_rtmp_rmemcpy(void *dst, const void* src, size_t n);

#define ngx_rtmp_rcpymem(dst, src, n) \
    (((u_char*)ngx_rtmp_rmemcpy(dst, src, n)) + (n))


static ngx_inline uint16_t
ngx_rtmp_r16(uint16_t n)
{
    return (n << 8) | (n >> 8);
}


static ngx_inline uint32_t
ngx_rtmp_r32(uint32_t n)
{
    return (n << 24) | ((n << 8) & 0xff0000) | ((n >> 8) & 0xff00) | (n >> 24);
}


static ngx_inline uint64_t
ngx_rtmp_r64(uint64_t n)
{
    return (uint64_t) ngx_rtmp_r32((uint32_t) n) << 32 |
                      ngx_rtmp_r32((uint32_t) (n >> 32));
}


/* Receiving messages */
ngx_int_t ngx_rtmp_receive_message(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h, ngx_chain_t *in);
ngx_int_t ngx_rtmp_protocol_message_handler(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h, ngx_chain_t *in);
ngx_int_t ngx_rtmp_user_message_handler(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h, ngx_chain_t *in);
ngx_int_t ngx_rtmp_aggregate_message_handler(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h, ngx_chain_t *in);
ngx_int_t ngx_rtmp_amf_message_handler(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h, ngx_chain_t *in);
ngx_int_t ngx_rtmp_amf_shared_object_handler(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h, ngx_chain_t *in);


/* Shared output buffers */

/* Store refcount in negative bytes of shared buffer */

#define NGX_RTMP_REFCOUNT_TYPE              uint32_t
#define NGX_RTMP_REFCOUNT_BYTES             sizeof(NGX_RTMP_REFCOUNT_TYPE)

#define ngx_rtmp_ref(b)                     \
    *((NGX_RTMP_REFCOUNT_TYPE*)(b) - 1)

#define ngx_rtmp_ref_set(b, v)              \
    ngx_rtmp_ref(b) = v

#define ngx_rtmp_ref_get(b)                 \
    ++ngx_rtmp_ref(b)

#define ngx_rtmp_ref_put(b)                 \
    --ngx_rtmp_ref(b)

#define ngx_rtmp_get_chunk_info(b)          \
    ((ngx_rtmp_chunk_info_t*)&ngx_rtmp_ref(b) - 1)

ngx_chain_t * ngx_rtmp_alloc_shared_buf(ngx_rtmp_core_srv_conf_t *cscf);
void ngx_rtmp_free_shared_chain(ngx_rtmp_core_srv_conf_t *cscf,
        ngx_chain_t *in);
ngx_chain_t * ngx_rtmp_append_shared_bufs(ngx_rtmp_core_srv_conf_t *cscf,
        ngx_chain_t *head, ngx_chain_t *in);

#define ngx_rtmp_acquire_shared_chain(in)   \
    ngx_rtmp_ref_get(in);                   \


/* Sending messages */
void ngx_rtmp_prepare_message(ngx_rtmp_session_t *s, ngx_rtmp_header_t *h,
        ngx_rtmp_header_t *lh, ngx_chain_t *out);
ngx_int_t ngx_rtmp_send_message(ngx_rtmp_session_t *s, ngx_chain_t *out,
        ngx_uint_t priority);

/* Note on priorities:
 * the bigger value the lower the priority.
 * priority=0 is the highest */


#define NGX_RTMP_LIMIT_SOFT         0
#define NGX_RTMP_LIMIT_HARD         1
#define NGX_RTMP_LIMIT_DYNAMIC      2

/* Protocol control messages */
ngx_chain_t * ngx_rtmp_create_chunk_size(ngx_rtmp_session_t *s,
        uint32_t chunk_size);
ngx_chain_t * ngx_rtmp_create_abort(ngx_rtmp_session_t *s,
        uint32_t csid);
ngx_chain_t * ngx_rtmp_create_ack(ngx_rtmp_session_t *s,
        uint32_t seq);
ngx_chain_t * ngx_rtmp_create_ack_size(ngx_rtmp_session_t *s,
        uint32_t ack_size);
ngx_chain_t * ngx_rtmp_create_bandwidth(ngx_rtmp_session_t *s,
        uint32_t ack_size, uint8_t limit_type);

ngx_int_t ngx_rtmp_send_chunk_size(ngx_rtmp_session_t *s,
        uint32_t chunk_size);
ngx_int_t ngx_rtmp_send_abort(ngx_rtmp_session_t *s,
        uint32_t csid);
ngx_int_t ngx_rtmp_send_ack(ngx_rtmp_session_t *s,
        uint32_t seq);
ngx_int_t ngx_rtmp_send_on_fcpublish(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h);
ngx_int_t ngx_rtmp_send_on_bw_done(ngx_rtmp_session_t *s,
        ngx_rtmp_header_t *h);
ngx_int_t ngx_rtmp_send_ack_size(ngx_rtmp_session_t *s,
        uint32_t ack_size);
ngx_int_t ngx_rtmp_send_bandwidth(ngx_rtmp_session_t *s,
        uint32_t ack_size, uint8_t limit_type);

/* User control messages */
ngx_chain_t * ngx_rtmp_create_stream_begin(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_chain_t * ngx_rtmp_create_stream_eof(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_chain_t * ngx_rtmp_create_stream_dry(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_chain_t * ngx_rtmp_create_set_buflen(ngx_rtmp_session_t *s,
        uint32_t msid, uint32_t buflen_msec);
ngx_chain_t * ngx_rtmp_create_recorded(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_chain_t * ngx_rtmp_create_ping_request(ngx_rtmp_session_t *s,
        uint32_t timestamp);
ngx_chain_t * ngx_rtmp_create_ping_response(ngx_rtmp_session_t *s,
        uint32_t timestamp);

ngx_int_t ngx_rtmp_send_stream_begin(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_int_t ngx_rtmp_send_stream_eof(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_int_t ngx_rtmp_send_stream_dry(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_int_t ngx_rtmp_send_set_buflen(ngx_rtmp_session_t *s,
        uint32_t msid, uint32_t buflen_msec);
ngx_int_t ngx_rtmp_send_recorded(ngx_rtmp_session_t *s,
        uint32_t msid);
ngx_int_t ngx_rtmp_send_ping_request(ngx_rtmp_session_t *s,
        uint32_t timestamp);
ngx_int_t ngx_rtmp_send_ping_response(ngx_rtmp_session_t *s,
        uint32_t timestamp);

/* AMF sender/receiver */
ngx_int_t ngx_rtmp_append_amf(ngx_rtmp_session_t *s,
        ngx_chain_t **first, ngx_chain_t **last,
        ngx_rtmp_amf_elt_t *elts, size_t nelts);
ngx_int_t ngx_rtmp_receive_amf(ngx_rtmp_session_t *s, ngx_chain_t *in,
        ngx_rtmp_amf_elt_t *elts, size_t nelts);

ngx_chain_t * ngx_rtmp_create_amf(ngx_rtmp_session_t *s, ngx_rtmp_header_t *h,
        ngx_rtmp_amf_elt_t *elts, size_t nelts);
ngx_int_t ngx_rtmp_send_amf(ngx_rtmp_session_t *s, ngx_rtmp_header_t *h,
        ngx_rtmp_amf_elt_t *elts, size_t nelts);

/* AMF status sender */
ngx_chain_t * ngx_rtmp_create_status(ngx_rtmp_session_t *s, char *code,
        char* level, char *desc);
ngx_chain_t * ngx_rtmp_create_play_status(ngx_rtmp_session_t *s, char *code,
        char* level, ngx_uint_t duration, ngx_uint_t bytes);
ngx_chain_t * ngx_rtmp_create_sample_access(ngx_rtmp_session_t *s);

ngx_int_t ngx_rtmp_send_status(ngx_rtmp_session_t *s, char *code,
        char* level, char *desc);
ngx_int_t ngx_rtmp_send_play_status(ngx_rtmp_session_t *s, char *code,
        char* level, ngx_uint_t duration, ngx_uint_t bytes);
ngx_int_t ngx_rtmp_send_sample_access(ngx_rtmp_session_t *s);


/* Frame types */
#define NGX_RTMP_VIDEO_KEY_FRAME            1
#define NGX_RTMP_VIDEO_INTER_FRAME          2
#define NGX_RTMP_VIDEO_DISPOSABLE_FRAME     3


static ngx_inline ngx_int_t
ngx_rtmp_get_video_frame_type(ngx_chain_t *in)
{
    return (in->buf->pos[0] & 0xf0) >> 4;
}


static ngx_inline ngx_int_t
ngx_rtmp_is_codec_header(ngx_chain_t *in)
{
    return in->buf->pos + 1 < in->buf->last && in->buf->pos[1] == 0;
}


static ngx_inline u_char *
ngx_strrlchr(u_char *p, u_char *first, u_char c)
{
    while (--p > first) {

        if (*p == c) {
            return p;
        }
    }

    return NULL;
}


extern ngx_rtmp_bandwidth_t                 ngx_rtmp_bw_out;
extern ngx_rtmp_bandwidth_t                 ngx_rtmp_bw_in;


extern ngx_uint_t                           ngx_rtmp_naccepted;
extern ngx_uint_t                           ngx_rtmp_hls_naccepted;
extern ngx_uint_t                           ngx_http_flv_naccepted;

#if (nginx_version >= 1007011)
extern ngx_queue_t                          ngx_rtmp_init_queue;
#elif (nginx_version >= 1007005)
extern ngx_thread_volatile ngx_queue_t      ngx_rtmp_init_queue;
#else
extern ngx_thread_volatile ngx_event_t     *ngx_rtmp_init_queue;
#endif

extern ngx_uint_t                           ngx_rtmp_max_module;
extern ngx_module_t                         ngx_rtmp_core_module;


#endif /* _NGX_RTMP_H_INCLUDED_ */