rtmp_connection_t *get_connection(rtmp_listening_t *ls,fd_t s)
{
rtmp_connection_t *c;
rtmp_event_t *rev, *wev;
mem_pool_t *pool;
rtmp_cycle_t *ngx_cycle;
ngx_cycle = ls->cycle;
c = ngx_cycle->free_connections;
if (c == NULL) {
ngx_drain_connections();
c = ngx_cycle->free_connections;
}
if (c == NULL) {
printf("there is not enough connections!\n");
return NULL;
}
ngx_cycle->free_connections = c->next;
rev = c->read;
wev = c->write;
pool = c->pool;
memset(c, 0, sizeof(rtmp_connection_t));
c->read = rev;
c->write = wev;
c->fd = s;
c->pool = pool;
memset(rev, 0 ,sizeof(rtmp_event_t));
memset(wev, 0, sizeof(rtmp_event_t));
rev->data = c;
wev->data = c;
wev->write = 1;
rev->index = -1;
wev->index = -1;
return c;
}
//从连接池中获取一个ngx_connection_t结构体，同时获取相应的读/写事件
ngx_connection_t *
ngx_get_connection(ngx_socket_t s/* 这条连接的套接字句柄 */, ngx_log_t *log)
{
ngx_uint_t instance;
ngx_event_t *rev, *wev;
ngx_connection_t *c;
/* disable warning: Win32 SOCKET is u_int while UNIX socket is int */
if (ngx_cycle->files && (ngx_uint_t) s >= ngx_cycle->files_n) {
ngx_log_error(NGX_LOG_ALERT, log, 0,
"the new socket has number %d, "
"but only %ui files are available",
s, ngx_cycle->files_n);
return NULL;
}
c = ngx_cycle->free_connections;
if (c == NULL) {
ngx_drain_connections();
c = ngx_cycle->free_connections;
}
if (c == NULL) {
ngx_log_error(NGX_LOG_ALERT, log, 0,
"%ui worker_connections are not enough",
ngx_cycle->connection_n);
return NULL;
}
ngx_cycle->free_connections = c->data;
ngx_cycle->free_connection_n--;
if (ngx_cycle->files) {
ngx_cycle->files[s] = c;
}
rev = c->read;
wev = c->write;
ngx_memzero(c, sizeof(ngx_connection_t));
c->read = rev;
c->write = wev;
c->fd = s;
c->log = log;
instance = rev->instance;
ngx_memzero(rev, sizeof(ngx_event_t));
ngx_memzero(wev, sizeof(ngx_event_t));
rev->instance = !instance;
wev->instance = !instance;
rev->index = NGX_INVALID_INDEX;
wev->index = NGX_INVALID_INDEX;
rev->data = c;
wev->data = c;
wev->write = 1;
return c;
}
/* 获取套接字对应的连接 */
ngx_connection_t *
ngx_get_connection(ngx_socket_t s, ngx_log_t *log)
{
ngx_uint_t instance;
ngx_event_t *rev, *wev;
ngx_connection_t *c;
/* disable warning: Win32 SOCKET is u_int while UNIX socket is int */
/* 如果超过了可以监听的最大文件数，则出错 */
if (ngx_cycle->files && (ngx_uint_t) s >= ngx_cycle->files_n) {
ngx_log_error(NGX_LOG_ALERT, log, 0,
"the new socket has number %d, "
"but only %ui files are available",
s, ngx_cycle->files_n);
return NULL;
}
c = ngx_cycle->free_connections;
/* 此时连接池已经被用完 */
if (c == NULL) {
/* 将一些keepalive的连接给释放掉 */
ngx_drain_connections();
c = ngx_cycle->free_connections;
}
if (c == NULL) {
ngx_log_error(NGX_LOG_ALERT, log, 0,
"%ui worker_connections are not enough",
ngx_cycle->connection_n);
return NULL;
}
ngx_cycle->free_connections = c->data;
ngx_cycle->free_connection_n--;
/* 设置套接字描述符对应的连接 */
if (ngx_cycle->files) {
ngx_cycle->files[s] = c;
}
rev = c->read;
wev = c->write;
/* 连接数据进行清除 */
ngx_memzero(c, sizeof(ngx_connection_t));
c->read = rev;
c->write = wev;
c->fd = s;
c->log = log;
instance = rev->instance;
ngx_memzero(rev, sizeof(ngx_event_t));
ngx_memzero(wev, sizeof(ngx_event_t));
rev->instance = !instance;
wev->instance = !instance;
rev->index = NGX_INVALID_INDEX;
wev->index = NGX_INVALID_INDEX;
/* 读写时间携带的数据是连接 */
rev->data = c;
wev->data = c;
wev->write = 1;
return c;
}
/* 从连接池中获取连接，并进行一些初始化 */
ngx_connection_t *
ngx_get_connection(ngx_socket_t s, ngx_log_t *log) //已经带上连接好的套接字，直接可以放入连接结构体
{
ngx_uint_t instance;
ngx_event_t *rev, *wev;
ngx_connection_t *c;
/* disable warning: Win32 SOCKET is u_int while UNIX socket is int */
if (ngx_cycle->files && (ngx_uint_t) s >= ngx_cycle->files_n) {
ngx_log_error(NGX_LOG_ALERT, log, 0,
"the new socket has number %d, "
"but only %ui files are available",
s, ngx_cycle->files_n);
return NULL;
}
/* ngx_mutex_lock */
//从连接池中获取一个空闲连接
c = ngx_cycle->free_connections;
if (c == NULL) {
ngx_drain_connections();// 将一些keepalive连接给释放掉
c = ngx_cycle->free_connections;
}
if (c == NULL) {
ngx_log_error(NGX_LOG_ALERT, log, 0,
"%ui worker_connections are not enough",
ngx_cycle->connection_n);
/* ngx_mutex_unlock */
return NULL;
}
ngx_cycle->free_connections = c->data; //c->data中的为next，空闲链接指向下一个，c指向的已被使用
ngx_cycle->free_connection_n--; //空闲连接数-1
/* ngx_mutex_unlock */
if (ngx_cycle->files) {
ngx_cycle->files[s] = c;
}
//使用指针保留原读写事件event
rev = c->read;
wev = c->write;
ngx_memzero(c, sizeof(ngx_connection_t)); //清空
c->read = rev; //使用之前保留的read事件
c->write = wev; //使用之前保留的write事件
c->fd = s;
c->log = log;
instance = rev->instance; //保留原过期标志位
//清空
ngx_memzero(rev, sizeof(ngx_event_t));
ngx_memzero(wev, sizeof(ngx_event_t));
//instance标志位置反，用于标示一个事件是否过期
rev->instance = !instance;
wev->instance = !instance;
rev->index = NGX_INVALID_INDEX;
wev->index = NGX_INVALID_INDEX;
//读写事件的data都指回连接本身
rev->data = c;
wev->data = c;
wev->write = 1;
return c;
}