static int
ngx_lcb_event_update(lcb_io_opt_t io, lcb_socket_t sock, void *event, short flags, void *data, ngx_lcb_handler_pt handler)
{
ngx_lcb_context_t *ctx = from_socket(sock);
ngx_int_t f;
ctx->handler = handler;
ctx->handler_mask = flags;
ctx->handler_data = data;
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
/* kqueue */
f = NGX_CLEAR_EVENT;
} else {
/* select, poll, /dev/poll */
f = NGX_LEVEL_EVENT;
}
/* FIXME check return value */
if (flags & LCB_WRITE_EVENT) {
ngx_add_event(ctx->peer->connection->write, NGX_WRITE_EVENT, f);
}
if (flags & LCB_READ_EVENT) {
ngx_add_event(ctx->peer->connection->read, NGX_READ_EVENT, f);
}
(void)io;
(void)event;
return 0;
}
ngx_int_t
ngx_handle_read_event(ngx_event_t *rev, ngx_uint_t flags)
{
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
/* kqueue, epoll */
if (!rev->active && !rev->ready) {
if (ngx_add_event(rev, NGX_READ_EVENT, NGX_CLEAR_EVENT) == NGX_ERROR) {
return NGX_ERROR;
}
}
return NGX_OK;
} else if (ngx_event_flags & NGX_USE_LEVEL_EVENT) {
/* select, poll, /dev/poll */
if (!rev->active && !rev->ready) {
if (ngx_add_event(rev, NGX_READ_EVENT, NGX_LEVEL_EVENT) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
if (rev->active && (rev->ready || (flags & NGX_CLOSE_EVENT))) {
if (ngx_del_event(rev, NGX_READ_EVENT, NGX_LEVEL_EVENT | flags) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
} else if (ngx_event_flags & NGX_USE_EVENTPORT_EVENT) {
/* event ports */
if (!rev->active && !rev->ready) {
if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
if (rev->oneshot && !rev->ready) {
if (ngx_del_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
}
/* aio, iocp, rtsig */
return NGX_OK;
}
static ngx_int_t
ngx_enable_accept_events(ngx_cycle_t *cycle)
{
ngx_uint_t i;
ngx_listening_t *ls;
ngx_connection_t *c;
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
c = ls[i].connection;
if (c->read->active) {
continue;
}
if (ngx_add_event(c->read, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
}
return NGX_OK;
}
void
ngx_http_upstream_dbd_init(ngx_http_request_t *r)
{
ngx_connection_t *c;
c = r->connection;
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
"http init upstream, client timer: %d", c->read->timer_set);
if (c->read->timer_set) {
ngx_del_timer(c->read);
}
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
if (!c->write->active) {
if (ngx_add_event(c->write, NGX_WRITE_EVENT, NGX_CLEAR_EVENT)
== NGX_ERROR)
{
ngx_http_finalize_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
return;
}
}
}
ngx_http_upstream_dbd_init_request(r);
}
// 遍历监听端口列表，加入epoll连接事件，开始接受请求
static ngx_int_t
ngx_enable_accept_events(ngx_cycle_t *cycle)
{
ngx_uint_t i;
ngx_listening_t *ls;
ngx_connection_t *c;
// 遍历监听端口列表
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
c = ls[i].connection;
// 如果连接已经监听（读事件激活）那么就跳过
// rtsig在nginx 1.9.x已经删除
if (c == NULL || c->read->active) {
continue;
}
// #define ngx_add_event ngx_event_actions.add
// 加入读事件，即接受连接事件
if (ngx_add_event(c->read, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
}
return NGX_OK;
}
static ngx_int_t
ngx_enable_accept_events(ngx_cycle_t *cycle)
{
ngx_uint_t i;
ngx_listening_t *ls;
ngx_connection_t *c;
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
c = ls[i].connection;
if (ngx_event_flags & NGX_USE_RTSIG_EVENT) {
if (ngx_add_conn(c) == NGX_ERROR) {
return NGX_ERROR;
}
} else {
if (ngx_add_event(c->read, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
}
}
return NGX_OK;
}
static void
ngx_lcb_upstream_init(ngx_http_request_t *r)
{
ngx_http_core_loc_conf_t *clcf;
ngx_lcb_connection_t *conn;
ngx_connection_t *c;
c = r->connection;
if (c->read->timer_set) {
ngx_del_timer(c->read);
}
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
if (!c->write->active) {
if (ngx_add_event(c->write, NGX_WRITE_EVENT, NGX_CLEAR_EVENT) == NGX_ERROR) {
ngx_http_finalize_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
return;
}
}
}
clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
conn = ngx_http_get_couchbase_connection(clcf->name);
if (conn == NULL) {
ngx_log_error(NGX_LOG_ERR, c->log, 0,
"couchbase: connection not found: \"%V\"", &clcf->name);
ngx_http_finalize_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
return;
}
if (conn->connected) {
/* the instance has been connected */
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
"couchbase(%p): connection to \"%s:%s\" ready. process request",
(void *)conn->lcb, lcb_get_host(conn->lcb), lcb_get_port(conn->lcb));
ngx_lcb_process(r);
} else {
lcb_error_t err;
ngx_http_request_t **rp;
rp = ngx_array_push(&conn->backlog);
if (rp == NULL) {
ngx_http_finalize_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
return;
}
*rp = r;
if (!conn->connect_scheduled) {
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
"couchbase(%p): connecting to \"%s:%s\"",
(void *)conn->lcb, lcb_get_host(conn->lcb), lcb_get_port(conn->lcb));
err = lcb_connect(conn->lcb);
if (err != LCB_SUCCESS) {
ngx_log_error(NGX_LOG_EMERG, c->log, 0,
"couchbase(%p): failed to initiate connection: 0x%02xd \"%s\"",
conn->lcb, err, lcb_strerror(NULL, err));
ngx_http_finalize_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
return;
}
conn->connect_scheduled = 1;
}
}
}
static void ngx_http_push_channel_handler(ngx_event_t *ev) {
//copypasta from os/unix/ngx_process_cycle.c (ngx_channel_handler)
ngx_int_t n;
ngx_channel_t ch;
ngx_connection_t *c;
if (ev->timedout) {
ev->timedout = 0;
return;
}
c = ev->data;
while(1) {
n = ngx_read_channel(c->fd, &ch, sizeof(ch), ev->log);
if (n == NGX_ERROR) {
if (ngx_event_flags & NGX_USE_EPOLL_EVENT) {
ngx_del_conn(c, 0);
}
ngx_close_connection(c);
return;
}
if ((ngx_event_flags & NGX_USE_EVENTPORT_EVENT) && (ngx_add_event(ev, NGX_READ_EVENT, 0) == NGX_ERROR)) {
return;
}
if (n == NGX_AGAIN) {
return;
}
//ngx_log_debug1(NGX_LOG_DEBUG_CORE, ev->log, 0, "push module: channel command: %d", ch.command);
if (ch.command==NGX_CMD_HTTP_PUSH_CHECK_MESSAGES) {
ngx_http_push_store->receive_worker_message();
}
}
}
static void
ngx_open_file_add_event(ngx_open_file_cache_t *cache,
ngx_cached_open_file_t *file, ngx_open_file_info_t *of, ngx_log_t *log)
{
ngx_open_file_cache_event_t *fev;
if (!(ngx_event_flags & NGX_USE_VNODE_EVENT)
|| !of->events
|| file->event
|| of->fd == NGX_INVALID_FILE
|| file->uses < of->min_uses)
{
return;
}
file->event = ngx_calloc(sizeof(ngx_event_t), log);
if (file->event== NULL) {
return;
}
fev = ngx_alloc(sizeof(ngx_open_file_cache_event_t), log);
if (fev == NULL) {
ngx_free(file->event);
file->event = NULL;
return;
}
fev->fd = of->fd;
fev->file = file;
fev->cache = cache;
file->event->handler = ngx_open_file_cache_remove;
file->event->data = fev;
/*
* although vnode event may be called while ngx_cycle->poll
* destruction, however, cleanup procedures are run before any
* memory freeing and events will be canceled.
*/
file->event->log = ngx_cycle->log;
if (ngx_add_event(file->event, NGX_VNODE_EVENT, NGX_ONESHOT_EVENT)
!= NGX_OK)
{
ngx_free(file->event->data);
ngx_free(file->event);
file->event = NULL;
return;
}
/*
* we do not file->use_event here because there may be a race
* condition between opening file and adding event, so we rely
* upon event notification only after first file revalidation
*/
return;
}
void
redis_nginx_add_write(void *privdata)
{
ngx_connection_t *connection = (ngx_connection_t *) privdata;
if (!connection->write->active && redis_nginx_fd_is_valid(connection->fd)) {
connection->write->handler = redis_nginx_write_event;
connection->write->log = connection->log;
if (ngx_add_event(connection->write, NGX_WRITE_EVENT, NGX_CLEAR_EVENT) == NGX_ERROR) {
ngx_log_error(NGX_LOG_ERR, ngx_cycle->log, 0, "redis_nginx_adapter: could not add write event to redis");
}
}
}
ngx_int_t
ngx_add_channel_event(ngx_cycle_t *cycle, ngx_fd_t fd, ngx_int_t event,
ngx_event_handler_pt handler)
{
syslog(LOG_INFO, "[%s:%s:%d]\n", __FILE__, __func__, __LINE__);
ngx_event_t *ev, *rev, *wev;
ngx_connection_t *c;
c = ngx_get_connection(fd, cycle->log);
if (c == NULL) {
return NGX_ERROR;
}
c->pool = cycle->pool;
rev = c->read;
wev = c->write;
rev->log = cycle->log;
wev->log = cycle->log;
#if (NGX_THREADS)
rev->lock = &c->lock;
wev->lock = &c->lock;
rev->own_lock = &c->lock;
wev->own_lock = &c->lock;
#endif
rev->channel = 1;
wev->channel = 1;
ev = (event == NGX_READ_EVENT) ? rev : wev;
ev->handler = handler;
if (ngx_add_conn && (ngx_event_flags & NGX_USE_EPOLL_EVENT) == 0) {
if (ngx_add_conn(c) == NGX_ERROR) {
ngx_free_connection(c);
return NGX_ERROR;
}
} else {
if (ngx_add_event(ev, event, 0) == NGX_ERROR) {
ngx_free_connection(c);
return NGX_ERROR;
}
}
return NGX_OK;
}
ngx_http_cache_add_file_event(ngx_http_cache_hash_t *hash,
ngx_http_cache_t *cache)
{
ngx_event_t *ev;
ngx_http_cache_event_ctx_t *ctx;
ev = &ngx_cycle->read_events[fd];
ngx_memzero(ev, sizeof(ngx_event_t);
ev->data = data;
ev->event_handler = ngx_http_cache_invalidate;
return ngx_add_event(ev, NGX_VNODE_EVENT, 0);
}
static ngx_connection_t* init_dummy_conn(void *data, int fd, ngx_event_handler_pt readhandler)
{
ngx_connection_t *c = calloc(1,sizeof(ngx_connection_t));
if (c == NULL) {
ngx_log_error(NGX_LOG_ERR, pcycle->log, 0, "calloc ngx_connection_t failed");
return NULL;
}
c->read = calloc(1,sizeof(ngx_event_t));
if (c->read == NULL) {
ngx_log_error(NGX_LOG_ERR, pcycle->log, 0, "calloc ngx_event_t failed");
free(c);
return NULL;
}
c->write = calloc(1,sizeof(ngx_event_t));
if (c->write == NULL) {
ngx_log_error(NGX_LOG_ERR, pcycle->log, 0, "calloc ngx_event_t failed");
free(c->read);
free(c);
return NULL;
}
if (ngx_nonblocking(fd) == -1) {
ngx_log_error(NGX_LOG_ALERT, pcycle->log, errno,
"init_dummy_conn ngx_nonblocking failed");
}
c->fd = fd;
c->data = data;
c->log = pcycle->log;
c->read->data = c;
c->read->log = pcycle->log;
c->read->handler = readhandler;
c->write->data = c;
c->write->log = pcycle->log;
c->write->handler = dummy_write_handler;
if (ngx_add_event(c->read, NGX_READ_EVENT, 0) == NGX_ERROR) {
ngx_log_error(NGX_LOG_INFO, pcycle->log, 0, "add dummy conn read event failed");
free(c->read);
free(c->write);
free(c);
return NULL;
}
return c;
}
/* Make sure the event handlers are activated. */
static ngx_int_t
ngx_http_gettoken_restore_handlers(ngx_connection_t *conn)
{
ngx_int_t rc;
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, conn->log, 0, "http_gettoken: Restoring event handlers. read=%d write=%d", conn->read->active, conn->write->active);
if (!conn->read->active) {
rc = ngx_add_event(conn->read, NGX_READ_EVENT, 0);
if (rc != NGX_OK) {
return rc;
}
}
if (!conn->write->active &&
(conn->write->handler != ngx_http_gettoken_dummy_write_handler)) {
rc = ngx_add_event(conn->write, NGX_WRITE_EVENT, 0);
if (rc != NGX_OK) {
return rc;
}
}
return NGX_OK;
}
ngx_int_t
ngx_add_channel_event(ngx_cycle_t *cycle, ngx_fd_t fd, ngx_int_t event, ngx_event_handler_pt handler)
{
ngx_event_t *ev, *rev, *wev;
ngx_connection_t *c;
c = ngx_get_connection(fd, cycle->log);
if (c == NULL)
{
return NGX_ERROR;
}
c->pool = cycle->pool;
rev = c->read;
wev = c->write;
rev->log = cycle->log;
wev->log = cycle->log;
rev->channel = 1;
wev->channel = 1;
ev = (event == NGX_READ_EVENT) ? rev : wev;
ev->handler = handler;
if (ngx_add_conn && (ngx_event_flags & NGX_USE_EPOLL_EVENT) == 0)
{
if (ngx_add_conn(c) == NGX_ERROR)
{
ngx_free_connection(c);
return NGX_ERROR;
}
}
else
{
if (ngx_add_event(ev, event, 0) == NGX_ERROR)
{
ngx_free_connection(c);
return NGX_ERROR;
}
}
return NGX_OK;
}
static void
ngx_http_push_stream_channel_handler(ngx_event_t *ev)
{
// copypaste from os/unix/ngx_process_cycle.c (ngx_channel_handler)
ngx_int_t n;
ngx_channel_t ch;
ngx_connection_t *c;
if (ev->timedout) {
ev->timedout = 0;
return;
}
c = ev->data;
while (1) {
n = ngx_read_channel(c->fd, &ch, sizeof(ch), ev->log);
if (n == NGX_ERROR) {
if (ngx_event_flags & NGX_USE_EPOLL_EVENT) {
ngx_del_conn(c, 0);
}
ngx_close_connection(c);
return;
}
if ((ngx_event_flags & NGX_USE_EVENTPORT_EVENT) && (ngx_add_event(ev, NGX_READ_EVENT, 0) == NGX_ERROR)) {
return;
}
if (n == NGX_AGAIN) {
return;
}
if (ch.command == NGX_CMD_HTTP_PUSH_STREAM_CHECK_MESSAGES.command) {
ngx_http_push_stream_process_worker_message();
} else if (ch.command == NGX_CMD_HTTP_PUSH_STREAM_CENSUS_SUBSCRIBERS.command) {
ngx_http_push_stream_census_worker_subscribers();
} else if (ch.command == NGX_CMD_HTTP_PUSH_STREAM_DELETE_CHANNEL.command) {
ngx_http_push_stream_delete_worker_channel();
}
}
}
ngx_int_t ipc_register_worker(ipc_t *ipc, ngx_cycle_t *cycle) {
int i;
ngx_connection_t *c;
ipc_process_t *proc;
for(i=0; i< NGX_MAX_PROCESSES; i++) {
proc = &ipc->process[i];
if(!proc->active) continue;
assert(proc->pipe[0] != NGX_INVALID_FILE);
assert(proc->pipe[1] != NGX_INVALID_FILE);
if(i==ngx_process_slot) {
//set up read connection
c = ngx_get_connection(proc->pipe[0], cycle->log);
c->data = ipc;
c->read->handler = ipc_read_handler;
c->read->log = cycle->log;
c->write->handler = NULL;
ngx_add_event(c->read, NGX_READ_EVENT, 0);
proc->c=c;
}
else {
//set up write connection
c = ngx_get_connection(proc->pipe[1], cycle->log);
c->data = proc;
c->read->handler = NULL;
c->write->log = cycle->log;
c->write->handler = ipc_write_handler;
proc->c=c;
}
}
return NGX_OK;
}
/* 将监听socket连接的读事件加入到监听事件中 */
static ngx_int_t
ngx_enable_accept_events(ngx_cycle_t *cycle)
{
ngx_uint_t i;
ngx_listening_t *ls;
ngx_connection_t *c;
/* 获取监听数组的首地址 */
ls = cycle->listening.elts;
/* 遍历整个监听数组 */
for (i = 0; i < cycle->listening.nelts; i++) {
/* 获取当前监听socket所对应的连接 */
c = ls[i].connection;
/* 当前连接的读事件是否处于active活跃状态 */
if (c->read->active) {
/* 若是处于active状态，表示该连接的读事件已经在事件监控对象中 */
continue;
}
/* 若当前连接没有加入到事件监控对象中，则将该链接注册到事件监控中 */
if (ngx_event_flags & NGX_USE_RTSIG_EVENT) {
if (ngx_add_conn(c) == NGX_ERROR) {
return NGX_ERROR;
}
} else {
/* 若当前连接的读事件不在事件监控对象中，则将其加入 */
if (ngx_add_event(c->read, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
}
}
return NGX_OK;
}
static ngx_int_t
ngx_enable_accept_events(ngx_cycle_t *cycle)
{
ngx_uint_t i;
ngx_listening_t *ls;
ngx_connection_t *c;
ls = cycle->listening.elts;
/*
注意:这里的循环会把所有的listening加入到了epoll中，那不是每个进程都会把所有的listening加入到epoll中吗，不是有惊群了吗?
答案:实际上在本进程ngx_enable_accept_events把所有listen加入本进程epoll中后，本进程获取到ngx_accept_mutex锁后，在执行accept事件的
过程中如果如果其他进程也开始ngx_trylock_accept_mutex，如果之前已经获取到锁，并把所有的listen添加到了epoll中，这时会因为没法获取到
accept锁，而把之前加入到本进程，但没有accept过的时间全部清除。和ngx_disable_accept_events配合使用
最终只有一个进程能accept到同一个客户端连接
*/
for (i = 0; i < cycle->listening.nelts; i++) {
c = ls[i].connection;
//后面的ngx_add_event->ngx_epoll_add_event中把listening中的c->read->active置1， ngx_epoll_del_event中把listening中置read->active置0
if (c == NULL || c->read->active) { //之前本进程已经accept成功的连接，不用再加入epoll事件中，避免重复
continue;
}
char tmpbuf[256];
snprintf(tmpbuf, sizeof(tmpbuf), "<%25s, %5d> epoll NGX_READ_EVENT(et) read add", NGX_FUNC_LINE);
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0, tmpbuf);
if (ngx_add_event(c->read, NGX_READ_EVENT, 0) == NGX_ERROR) { //ngx_epoll_add_event
return NGX_ERROR;
}
}
return NGX_OK;
}
ngx_int_t
ngx_zeromq_connect(ngx_peer_connection_t *pc)
{
ngx_connection_t *c;
ngx_event_t *rev, *wev;
void *zmq;
int fd, zero;
size_t fdsize;
zmq = zmq_socket(zmq_context, ZMQ_REQ);
if (zmq == NULL) {
ngx_zeromq_log_error(pc->log, "zmq_socket(ZMQ_REQ)");
return NGX_ERROR;
}
fdsize = sizeof(int);
if (zmq_getsockopt(zmq, ZMQ_FD, &fd, &fdsize) == -1) {
ngx_zeromq_log_error(pc->log, "zmq_getsockopt(ZMQ_FD)");
goto failed_zmq;
}
zero = 0;
if (zmq_setsockopt(zmq, ZMQ_LINGER, &zero, sizeof(int)) == -1) {
ngx_zeromq_log_error(pc->log, "zmq_setsockopt(ZMQ_LINGER)");
goto failed_zmq;
}
c = ngx_get_connection(fd, pc->log);
if (c == NULL) {
goto failed_zmq;
}
c->data = zmq;
c->recv = ngx_zeromq_recv;
c->send = ngx_zeromq_send;
c->recv_chain = ngx_zeromq_recv_chain;
c->send_chain = ngx_zeromq_send_chain;
/* This won't fly with ZeroMQ */
c->sendfile = 0;
c->tcp_nopush = NGX_TCP_NOPUSH_DISABLED;
c->tcp_nodelay = NGX_TCP_NODELAY_DISABLED;
c->log_error = pc->log_error;
rev = c->read;
wev = c->write;
rev->log = pc->log;
wev->log = pc->log;
pc->connection = c;
c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
if (pc->local) {
ngx_log_error(NGX_LOG_WARN, pc->log, 0,
"zmq_connect: binding to local address is not supported");
}
if (zmq_connect(zmq, (const char *) pc->data) == -1) {
ngx_zeromq_log_error(pc->log, "zmq_connect()");
goto failed;
}
ngx_log_debug4(NGX_LOG_DEBUG_EVENT, pc->log, 0,
"zmq_connect: lazily connected to tcp://%V,"
" zmq:%p fd:%d #%d", pc->name, zmq, fd, c->number);
if (ngx_add_conn) {
/* rtsig */
if (ngx_add_conn(c) == NGX_ERROR) {
goto failed;
}
} else {
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
/* kqueue, epoll */
if (ngx_add_event(rev, NGX_READ_EVENT, NGX_CLEAR_EVENT) != NGX_OK) {
goto failed;
}
} else {
/* select, poll, /dev/poll */
if (ngx_add_event(rev, NGX_READ_EVENT, NGX_LEVEL_EVENT) != NGX_OK) {
goto failed;
}
}
}
/*
* ZeroMQ assumes that new socket is read-ready (but it really isn't)
* and it won't notify us about any new events if we don't fail to read
* from it first. Sigh.
*/
rev->ready = 1;
wev->ready = 1;
return NGX_OK;
failed:
ngx_free_connection(c);
c->fd = (ngx_socket_t) -1;
failed_zmq:
if (zmq_close(zmq) == -1) {
ngx_zeromq_log_error(pc->log, "zmq_close()");
}
return NGX_ERROR;
}
static ngx_int_t
ngx_event_process_init(ngx_cycle_t *cycle)
{
ngx_uint_t m, i;
ngx_event_t *rev, *wev;
ngx_listening_t *ls;
ngx_connection_t *c, *next, *old;
ngx_core_conf_t *ccf;
ngx_event_conf_t *ecf;
ngx_event_module_t *module;
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
ecf = ngx_event_get_conf(cycle->conf_ctx, ngx_event_core_module);
if (ccf->master && ccf->worker_processes > 1 && ecf->accept_mutex) {
ngx_use_accept_mutex = 1;
ngx_accept_mutex_held = 0;
ngx_accept_mutex_delay = ecf->accept_mutex_delay;
} else {
ngx_use_accept_mutex = 0;
}
#if (NGX_WIN32)
/*
* disable accept mutex on win32 as it may cause deadlock if
* grabbed by a process which can't accept connections
*/
ngx_use_accept_mutex = 0;
#endif
#if (NGX_THREADS)
ngx_posted_events_mutex = ngx_mutex_init(cycle->log, 0);
if (ngx_posted_events_mutex == NULL) {
return NGX_ERROR;
}
#endif
if (ngx_event_timer_init(cycle->log) == NGX_ERROR) {
return NGX_ERROR;
}
for (m = 0; ngx_modules[m]; m++) {
if (ngx_modules[m]->type != NGX_EVENT_MODULE) {
continue;
}
if (ngx_modules[m]->ctx_index != ecf->use) {
continue;
}
module = ngx_modules[m]->ctx;
if (module->actions.init(cycle, ngx_timer_resolution) != NGX_OK) {
/* fatal */
exit(2);
}
break;
}
#if !(NGX_WIN32)
if (ngx_timer_resolution && !(ngx_event_flags & NGX_USE_TIMER_EVENT)) {
struct sigaction sa;
struct itimerval itv;
ngx_memzero(&sa, sizeof(struct sigaction));
sa.sa_handler = ngx_timer_signal_handler;
sigemptyset(&sa.sa_mask);
if (sigaction(SIGALRM, &sa, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"sigaction(SIGALRM) failed");
return NGX_ERROR;
}
itv.it_interval.tv_sec = ngx_timer_resolution / 1000;
itv.it_interval.tv_usec = (ngx_timer_resolution % 1000) * 1000;
itv.it_value.tv_sec = ngx_timer_resolution / 1000;
itv.it_value.tv_usec = (ngx_timer_resolution % 1000 ) * 1000;
if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setitimer() failed");
}
}
if (ngx_event_flags & NGX_USE_FD_EVENT) {
struct rlimit rlmt;
if (getrlimit(RLIMIT_NOFILE, &rlmt) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"getrlimit(RLIMIT_NOFILE) failed");
return NGX_ERROR;
}
cycle->files_n = (ngx_uint_t) rlmt.rlim_cur;
cycle->files = ngx_calloc(sizeof(ngx_connection_t *) * cycle->files_n,
cycle->log);
if (cycle->files == NULL) {
return NGX_ERROR;
}
}
#endif
cycle->connections =
ngx_alloc(sizeof(ngx_connection_t) * cycle->connection_n, cycle->log);
if (cycle->connections == NULL) {
return NGX_ERROR;
}
c = cycle->connections;
cycle->read_events = ngx_alloc(sizeof(ngx_event_t) * cycle->connection_n,
cycle->log);
if (cycle->read_events == NULL) {
return NGX_ERROR;
}
rev = cycle->read_events;
for (i = 0; i < cycle->connection_n; i++) {
rev[i].closed = 1;
rev[i].instance = 1;
#if (NGX_THREADS)
rev[i].lock = &c[i].lock;
rev[i].own_lock = &c[i].lock;
#endif
}
cycle->write_events = ngx_alloc(sizeof(ngx_event_t) * cycle->connection_n,
cycle->log);
if (cycle->write_events == NULL) {
return NGX_ERROR;
}
wev = cycle->write_events;
for (i = 0; i < cycle->connection_n; i++) {
wev[i].closed = 1;
#if (NGX_THREADS)
wev[i].lock = &c[i].lock;
wev[i].own_lock = &c[i].lock;
#endif
}
i = cycle->connection_n;
next = NULL;
do {
i--;
c[i].data = next;
c[i].read = &cycle->read_events[i];
c[i].write = &cycle->write_events[i];
c[i].fd = (ngx_socket_t) -1;
next = &c[i];
#if (NGX_THREADS)
c[i].lock = 0;
#endif
} while (i);
cycle->free_connections = next;
cycle->free_connection_n = cycle->connection_n;
/* for each listening socket */
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
c = ngx_get_connection(ls[i].fd, cycle->log);
if (c == NULL) {
return NGX_ERROR;
}
c->log = &ls[i].log;
c->listening = &ls[i];
ls[i].connection = c;
rev = c->read;
rev->log = c->log;
rev->accept = 1;
#if (NGX_HAVE_DEFERRED_ACCEPT)
rev->deferred_accept = ls[i].deferred_accept;
#endif
if (!(ngx_event_flags & NGX_USE_IOCP_EVENT)) {
if (ls[i].previous) {
/*
* delete the old accept events that were bound to
* the old cycle read events array
*/
old = ls[i].previous->connection;
if (ngx_del_event(old->read, NGX_READ_EVENT, NGX_CLOSE_EVENT)
== NGX_ERROR)
{
return NGX_ERROR;
}
old->fd = (ngx_socket_t) -1;
}
}
#if (NGX_WIN32)
if (ngx_event_flags & NGX_USE_IOCP_EVENT) {
ngx_iocp_conf_t *iocpcf;
rev->handler = ngx_event_acceptex;
if (ngx_use_accept_mutex) {
continue;
}
if (ngx_add_event(rev, 0, NGX_IOCP_ACCEPT) == NGX_ERROR) {
return NGX_ERROR;
}
ls[i].log.handler = ngx_acceptex_log_error;
iocpcf = ngx_event_get_conf(cycle->conf_ctx, ngx_iocp_module);
if (ngx_event_post_acceptex(&ls[i], iocpcf->post_acceptex)
== NGX_ERROR)
{
return NGX_ERROR;
}
} else {
rev->handler = ngx_event_accept;
if (ngx_use_accept_mutex) {
continue;
}
if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
}
#else
rev->handler = ngx_event_accept;
if (ngx_use_accept_mutex) {
continue;
}
if (ngx_event_flags & NGX_USE_RTSIG_EVENT) {
if (ngx_add_conn(c) == NGX_ERROR) {
return NGX_ERROR;
}
} else {
if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
}
#endif
}
return NGX_OK;
}
ngx_int_t
ngx_event_connect_peer(ngx_peer_connection_t *pc)
{
int rc, type;
#if (NGX_HAVE_IP_BIND_ADDRESS_NO_PORT || NGX_LINUX)
in_port_t port;
#endif
ngx_int_t event;
ngx_err_t err;
ngx_uint_t level;
ngx_socket_t s;
ngx_event_t *rev, *wev;
ngx_connection_t *c;
rc = pc->get(pc, pc->data);
if (rc != NGX_OK) {
return rc;
}
type = (pc->type ? pc->type : SOCK_STREAM);
s = ngx_socket(pc->sockaddr->sa_family, type, 0);
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, pc->log, 0, "%s socket %d",
(type == SOCK_STREAM) ? "stream" : "dgram", s);
if (s == (ngx_socket_t) -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_socket_n " failed");
return NGX_ERROR;
}
c = ngx_get_connection(s, pc->log);
if (c == NULL) {
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_close_socket_n "failed");
}
return NGX_ERROR;
}
c->type = type;
if (pc->rcvbuf) {
if (setsockopt(s, SOL_SOCKET, SO_RCVBUF,
(const void *) &pc->rcvbuf, sizeof(int)) == -1)
{
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
"setsockopt(SO_RCVBUF) failed");
goto failed;
}
}
if (ngx_nonblocking(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_nonblocking_n " failed");
goto failed;
}
if (pc->local) {
#if (NGX_HAVE_TRANSPARENT_PROXY)
if (pc->transparent) {
if (ngx_event_connect_set_transparent(pc, s) != NGX_OK) {
goto failed;
}
}
#endif
#if (NGX_HAVE_IP_BIND_ADDRESS_NO_PORT || NGX_LINUX)
port = ngx_inet_get_port(pc->local->sockaddr);
#endif
#if (NGX_HAVE_IP_BIND_ADDRESS_NO_PORT)
if (pc->sockaddr->sa_family != AF_UNIX && port == 0) {
static int bind_address_no_port = 1;
if (bind_address_no_port) {
if (setsockopt(s, IPPROTO_IP, IP_BIND_ADDRESS_NO_PORT,
(const void *) &bind_address_no_port,
sizeof(int)) == -1)
{
err = ngx_socket_errno;
if (err != NGX_EOPNOTSUPP && err != NGX_ENOPROTOOPT) {
ngx_log_error(NGX_LOG_ALERT, pc->log, err,
"setsockopt(IP_BIND_ADDRESS_NO_PORT) "
"failed, ignored");
} else {
bind_address_no_port = 0;
}
}
}
}
#endif
#if (NGX_LINUX)
if (pc->type == SOCK_DGRAM && port != 0) {
int reuse_addr = 1;
if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
(const void *) &reuse_addr, sizeof(int))
== -1)
{
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
"setsockopt(SO_REUSEADDR) failed");
goto failed;
}
}
#endif
if (bind(s, pc->local->sockaddr, pc->local->socklen) == -1) {
ngx_log_error(NGX_LOG_CRIT, pc->log, ngx_socket_errno,
"bind(%V) failed", &pc->local->name);
goto failed;
}
}
if (type == SOCK_STREAM) {
c->recv = ngx_recv;
c->send = ngx_send;
c->recv_chain = ngx_recv_chain;
c->send_chain = ngx_send_chain;
c->sendfile = 1;
if (pc->sockaddr->sa_family == AF_UNIX) {
c->tcp_nopush = NGX_TCP_NOPUSH_DISABLED;
c->tcp_nodelay = NGX_TCP_NODELAY_DISABLED;
#if (NGX_SOLARIS)
/* Solaris's sendfilev() supports AF_NCA, AF_INET, and AF_INET6 */
c->sendfile = 0;
#endif
}
} else { /* type == SOCK_DGRAM */
c->recv = ngx_udp_recv;
c->send = ngx_send;
c->send_chain = ngx_udp_send_chain;
}
c->log_error = pc->log_error;
rev = c->read;
wev = c->write;
rev->log = pc->log;
wev->log = pc->log;
pc->connection = c;
c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
if (ngx_add_conn) {
if (ngx_add_conn(c) == NGX_ERROR) {
goto failed;
}
}
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, pc->log, 0,
"connect to %V, fd:%d #%uA", pc->name, s, c->number);
rc = connect(s, pc->sockaddr, pc->socklen);
if (rc == -1) {
err = ngx_socket_errno;
if (err != NGX_EINPROGRESS
#if (NGX_WIN32)
/* Winsock returns WSAEWOULDBLOCK (NGX_EAGAIN) */
&& err != NGX_EAGAIN
#endif
)
{
if (err == NGX_ECONNREFUSED
#if (NGX_LINUX)
/*
* Linux returns EAGAIN instead of ECONNREFUSED
* for unix sockets if listen queue is full
*/
|| err == NGX_EAGAIN
#endif
|| err == NGX_ECONNRESET
|| err == NGX_ENETDOWN
|| err == NGX_ENETUNREACH
|| err == NGX_EHOSTDOWN
|| err == NGX_EHOSTUNREACH)
{
level = NGX_LOG_ERR;
} else {
level = NGX_LOG_CRIT;
}
ngx_log_error(level, c->log, err, "connect() to %V failed",
pc->name);
ngx_close_connection(c);
pc->connection = NULL;
return NGX_DECLINED;
}
}
if (ngx_add_conn) {
if (rc == -1) {
/* NGX_EINPROGRESS */
return NGX_AGAIN;
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected");
wev->ready = 1;
return NGX_OK;
}
if (ngx_event_flags & NGX_USE_IOCP_EVENT) {
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, pc->log, ngx_socket_errno,
"connect(): %d", rc);
if (ngx_blocking(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_blocking_n " failed");
goto failed;
}
/*
* FreeBSD's aio allows to post an operation on non-connected socket.
* NT does not support it.
*
* TODO: check in Win32, etc. As workaround we can use NGX_ONESHOT_EVENT
*/
rev->ready = 1;
wev->ready = 1;
return NGX_OK;
}
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
/* kqueue */
event = NGX_CLEAR_EVENT;
} else {
/* select, poll, /dev/poll */
event = NGX_LEVEL_EVENT;
}
if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) {
goto failed;
}
if (rc == -1) {
/* NGX_EINPROGRESS */
if (ngx_add_event(wev, NGX_WRITE_EVENT, event) != NGX_OK) {
goto failed;
}
return NGX_AGAIN;
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected");
wev->ready = 1;
return NGX_OK;
failed:
ngx_close_connection(c);
pc->connection = NULL;
return NGX_ERROR;
}
/*
* [analy] 加入读事件到epoll事件处理队列中（根据触发模式有不通的处理方式）
*/
ngx_int_t
ngx_handle_read_event(ngx_event_t *rev, ngx_uint_t flags)
{
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) { /* [analy] 使用edge triggered */
/* kqueue, epoll */
if (!rev->active && !rev->ready) { // 当此事件处于非活跃状态时(即没有被添加到epoll事件监控队列中时)， rev->ready是此连接没有读事件到来
if (ngx_add_event(rev, NGX_READ_EVENT, NGX_CLEAR_EVENT) /* [analy] 调用ngx_epoll_add_event()， 当使用epoll时，宏NGX_CLEAR_EVENT被定义成 EPOLLET */
== NGX_ERROR)
{
return NGX_ERROR;
}
}
return NGX_OK;
} else if (ngx_event_flags & NGX_USE_LEVEL_EVENT) { /* [analy] 使用level triggered */
/* select, poll, /dev/poll */
if (!rev->active && !rev->ready) {
if (ngx_add_event(rev, NGX_READ_EVENT, NGX_LEVEL_EVENT)
== NGX_ERROR)
{
return NGX_ERROR;
}
return NGX_OK;
}
if (rev->active && (rev->ready || (flags & NGX_CLOSE_EVENT))) {
if (ngx_del_event(rev, NGX_READ_EVENT, NGX_LEVEL_EVENT | flags)
== NGX_ERROR)
{
return NGX_ERROR;
}
return NGX_OK;
}
} else if (ngx_event_flags & NGX_USE_EVENTPORT_EVENT) {
/* event ports */
if (!rev->active && !rev->ready) {
if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
if (rev->oneshot && !rev->ready) {
if (ngx_del_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
}
/* aio, iocp, rtsig */
return NGX_OK;
}
/*
* [analy] 将写事件添加到事件处理队列中
* 参数 lowat: 如果大于0，将设置发送缓冲区的低潮阀值
*/
ngx_int_t
ngx_handle_write_event(ngx_event_t *wev, size_t lowat)
{
ngx_connection_t *c;
if (lowat) {
// 设置发送缓冲区的低潮阀值
c = wev->data;
if (ngx_send_lowat(c, lowat) == NGX_ERROR) {
return NGX_ERROR;
}
}
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) { // 使用edge triggered 模式
/* kqueue, epoll */
// 此事件未加入epoll事件队列中时，将添加写事件。
if (!wev->active && !wev->ready) {
if (ngx_add_event(wev, NGX_WRITE_EVENT,
NGX_CLEAR_EVENT | (lowat ? NGX_LOWAT_EVENT : 0)) // NGX_CLEAR_EVENT = EPOLLET
== NGX_ERROR)
{
return NGX_ERROR;
}
}
return NGX_OK;
} else if (ngx_event_flags & NGX_USE_LEVEL_EVENT) { // 使用level triggerred模式
/* select, poll, /dev/poll */
if (!wev->active && !wev->ready) {
if (ngx_add_event(wev, NGX_WRITE_EVENT, NGX_LEVEL_EVENT)
== NGX_ERROR)
{
return NGX_ERROR;
}
return NGX_OK;
}
if (wev->active && wev->ready) {
if (ngx_del_event(wev, NGX_WRITE_EVENT, NGX_LEVEL_EVENT)
== NGX_ERROR)
{
return NGX_ERROR;
}
return NGX_OK;
}
} else if (ngx_event_flags & NGX_USE_EVENTPORT_EVENT) {
/* event ports */
if (!wev->active && !wev->ready) {
if (ngx_add_event(wev, NGX_WRITE_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
if (wev->oneshot && wev->ready) {
if (ngx_del_event(wev, NGX_WRITE_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
}
/* aio, iocp, rtsig */
return NGX_OK;
}
static void
ngx_channel_handler(ngx_event_t *ev)
{
ngx_int_t n;
ngx_channel_t ch;
ngx_connection_t *c;
if (ev->timedout) {
ev->timedout = 0;
return;
}
c = ev->data;
ngx_log_debug0(NGX_LOG_DEBUG_CORE, ev->log, 0, "channel handler");
for ( ;; ) {
n = ngx_read_channel(c->fd, &ch, sizeof(ngx_channel_t), ev->log);
ngx_log_debug1(NGX_LOG_DEBUG_CORE, ev->log, 0, "channel: %i", n);
if (n == NGX_ERROR) {
if (ngx_event_flags & NGX_USE_EPOLL_EVENT) {
ngx_del_conn(c, 0);
}
ngx_close_connection(c);
return;
}
if (ngx_event_flags & NGX_USE_EVENTPORT_EVENT) {
if (ngx_add_event(ev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return;
}
}
if (n == NGX_AGAIN) {
return;
}
ngx_log_debug1(NGX_LOG_DEBUG_CORE, ev->log, 0,
"channel command: %d", ch.command);
switch (ch.command) {
case NGX_CMD_QUIT:
ngx_quit = 1;
break;
case NGX_CMD_TERMINATE:
ngx_terminate = 1;
break;
case NGX_CMD_REOPEN:
ngx_reopen = 1;
break;
case NGX_CMD_OPEN_CHANNEL:
ngx_log_debug3(NGX_LOG_DEBUG_CORE, ev->log, 0,
"get channel s:%i pid:%P fd:%d",
ch.slot, ch.pid, ch.fd);
ngx_processes[ch.slot].pid = ch.pid;
ngx_processes[ch.slot].channel[0] = ch.fd;
break;
case NGX_CMD_CLOSE_CHANNEL:
ngx_log_debug4(NGX_LOG_DEBUG_CORE, ev->log, 0,
"close channel s:%i pid:%P our:%P fd:%d",
ch.slot, ch.pid, ngx_processes[ch.slot].pid,
ngx_processes[ch.slot].channel[0]);
if (close(ngx_processes[ch.slot].channel[0]) == -1) {
ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno,
"close() channel failed");
}
ngx_processes[ch.slot].channel[0] = -1;
break;
}
}
}
static ngx_int_t
ngx_http_lua_udp_connect(ngx_udp_connection_t *uc)
{
int rc;
ngx_int_t event;
ngx_event_t *rev, *wev;
ngx_socket_t s;
ngx_connection_t *c;
s = ngx_socket(uc->sockaddr->sa_family, SOCK_DGRAM, 0);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, &uc->log, 0, "UDP socket %d", s);
if (s == -1) {
ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
ngx_socket_n " failed");
return NGX_ERROR;
}
c = ngx_get_connection(s, &uc->log);
if (c == NULL) {
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
ngx_close_socket_n "failed");
}
return NGX_ERROR;
}
if (ngx_nonblocking(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
ngx_nonblocking_n " failed");
ngx_free_connection(c);
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
ngx_close_socket_n " failed");
}
return NGX_ERROR;
}
rev = c->read;
wev = c->write;
rev->log = &uc->log;
wev->log = &uc->log;
uc->connection = c;
c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
#if (NGX_THREADS)
/* TODO: lock event when call completion handler */
rev->lock = &c->lock;
wev->lock = &c->lock;
rev->own_lock = &c->lock;
wev->own_lock = &c->lock;
#endif
#if (NGX_HTTP_LUA_HAVE_SO_PASSCRED)
if (uc->sockaddr->sa_family == AF_UNIX) {
struct sockaddr addr;
addr.sa_family = AF_UNIX;
/* just to make valgrind happy */
ngx_memzero(addr.sa_data, sizeof(addr.sa_data));
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, &uc->log, 0, "datagram unix "
"domain socket autobind");
if (bind(uc->connection->fd, &addr, sizeof(sa_family_t)) != 0) {
ngx_log_error(NGX_LOG_CRIT, &uc->log, ngx_socket_errno,
"bind() failed");
return NGX_ERROR;
}
}
#endif
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, &uc->log, 0,
"connect to %V, fd:%d #%d", &uc->server, s, c->number);
rc = connect(s, uc->sockaddr, uc->socklen);
/* TODO: aio, iocp */
if (rc == -1) {
ngx_log_error(NGX_LOG_CRIT, &uc->log, ngx_socket_errno,
"connect() failed");
return NGX_ERROR;
}
/* UDP sockets are always ready to write */
wev->ready = 1;
if (ngx_add_event) {
event = (ngx_event_flags & NGX_USE_CLEAR_EVENT) ?
/* kqueue, epoll */ NGX_CLEAR_EVENT:
/* select, poll, /dev/poll */ NGX_LEVEL_EVENT;
/* eventport event type has no meaning: oneshot only */
if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) {
return NGX_ERROR;
}
} else {
/* rtsig */
if (ngx_add_conn(c) == NGX_ERROR) {
return NGX_ERROR;
}
}
return NGX_OK;
}
static ngx_int_t
ngx_rtmp_exec_run(ngx_rtmp_exec_t *e)
{
#if !(NGX_WIN32)
ngx_pid_t pid;
int fd, maxfd;
int pipefd[2];
int ret;
ngx_rtmp_exec_conf_t *ec;
ngx_str_t *arg, a;
char **args;
ngx_uint_t n;
ec = e->conf;
ngx_log_debug1(NGX_LOG_DEBUG_RTMP, e->log, 0,
"exec: starting child '%V'", &ec->cmd);
if (e->active) {
ngx_log_debug1(NGX_LOG_DEBUG_RTMP, e->log, 0,
"exec: already active '%V'", &ec->cmd);
return NGX_OK;
}
if (pipe(pipefd) == -1) {
ngx_log_error(NGX_LOG_INFO, e->log, ngx_errno,
"exec: pipe failed");
return NGX_ERROR;
}
/* make pipe write end survive through exec */
ret = fcntl(pipefd[1], F_GETFD);
if (ret != -1) {
ret &= ~FD_CLOEXEC;
ret = fcntl(pipefd[1], F_SETFD, ret);
}
if (ret == -1) {
close(pipefd[0]);
close(pipefd[1]);
ngx_log_error(NGX_LOG_INFO, e->log, ngx_errno,
"exec: fcntl failed");
return NGX_ERROR;
}
pid = fork();
switch (pid) {
case -1:
close(pipefd[0]);
close(pipefd[1]);
ngx_log_error(NGX_LOG_INFO, e->log, ngx_errno,
"exec: fork failed");
return NGX_ERROR;
case 0:
/* child */
#if (NGX_LINUX)
prctl(PR_SET_PDEATHSIG, e->kill_signal, 0, 0, 0);
#endif
/* close all descriptors but pipe write end */
maxfd = sysconf(_SC_OPEN_MAX);
for (fd = 0; fd < maxfd; ++fd) {
if (fd == pipefd[1]) {
continue;
}
close(fd);
}
fd = open("/dev/null", O_RDWR);
dup2(fd, STDIN_FILENO);
dup2(fd, STDOUT_FILENO);
dup2(fd, STDERR_FILENO);
args = ngx_alloc((ec->args.nelts + 2) * sizeof(char *), e->log);
if (args == NULL) {
exit(1);
}
arg = ec->args.elts;
args[0] = (char *) ec->cmd.data;
for (n = 0; n < ec->args.nelts; ++n, ++arg) {
if (e->session == NULL) {
a = *arg;
} else {
ngx_rtmp_eval(e->session, arg, ngx_rtmp_exec_eval_p, &a);
}
args[n + 1] = (char *) a.data;
}
args[n + 1] = NULL;
if (execvp((char *) ec->cmd.data, args) == -1) {
exit(1);
}
break;
default:
/* parent */
close(pipefd[1]);
e->active = 1;
e->pid = pid;
e->pipefd = pipefd[0];
if (e->save_pid) {
*e->save_pid = pid;
}
e->dummy_conn.fd = e->pipefd;
e->dummy_conn.data = e;
e->dummy_conn.read = &e->read_evt;
e->dummy_conn.write = &e->write_evt;
e->read_evt.data = &e->dummy_conn;
e->write_evt.data = &e->dummy_conn;
e->read_evt.log = e->log;
e->read_evt.handler = ngx_rtmp_exec_child_dead;
if (ngx_add_event(&e->read_evt, NGX_READ_EVENT, 0) != NGX_OK) {
ngx_log_error(NGX_LOG_INFO, e->log, ngx_errno,
"exec: failed to add child control event");
}
ngx_log_debug2(NGX_LOG_DEBUG_RTMP, e->log, 0,
"exec: child '%V' started pid=%i",
&ec->cmd, (ngx_int_t) pid);
break;
}
#endif /* NGX_WIN32 */
return NGX_OK;
}
static ngx_int_t
ngx_event_process_init(ngx_cycle_t *cycle)
{
ngx_uint_t m, i;
ngx_event_t *rev, *wev;
ngx_listening_t *ls;
ngx_connection_t *c, *next, *old;
ngx_core_conf_t *ccf;
ngx_event_conf_t *ecf;
ngx_event_module_t *module;
ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
ecf = ngx_event_get_conf(cycle->conf_ctx, ngx_event_core_module);
/* [analy] ngx_use_accept_mutex表示是否需要通过对accept加锁来解决惊群问题。
当nginx worker进程数>1时且配置文件中打开accept_mutex时，这个标志置为1
*/
if (ccf->master && ccf->worker_processes > 1 && ecf->accept_mutex) {
ngx_use_accept_mutex = 1;
ngx_accept_mutex_held = 0;
ngx_accept_mutex_delay = ecf->accept_mutex_delay;
} else {
ngx_use_accept_mutex = 0;
}
#if (NGX_THREADS)
ngx_posted_events_mutex = ngx_mutex_init(cycle->log, 0);
if (ngx_posted_events_mutex == NULL) {
return NGX_ERROR;
}
#endif
/* [analy] ??????????? */
if (ngx_event_timer_init(cycle->log) == NGX_ERROR) {
return NGX_ERROR;
}
/* [analy] 调用事件处理模块(epoll)初始化函数 */
for (m = 0; ngx_modules[m]; m++) {
if (ngx_modules[m]->type != NGX_EVENT_MODULE) {
continue;
}
if (ngx_modules[m]->ctx_index != ecf->use) {
continue;
}
/* [analy]
由于Nginx实现了很多的事件模块，比如：epoll，poll，select, kqueue,aio
（这些模块位于src/event/modules目录中）等等，所以Nginx对事件模块进行
了一层抽象，方便在不同的系统上使用不同的事件模型，也便于扩展新的事件
模型
此处的init回调，其实就是调用了ngx_epoll_init函数。module->actions结构
封装了epoll的所有接口函数。Nginx就是通过actions结构将epoll注册到事件
抽象层中。actions的类型是ngx_event_actions_t
*/
module = ngx_modules[m]->ctx;
if (module->actions.init(cycle, ngx_timer_resolution) != NGX_OK) {
/* fatal */
exit(2);
}
break;
}
#if !(NGX_WIN32)
/*
* timer_resolution指令指定了时间，并且未指定NGX_USE_TIMER_EVENT标记时，
* 根据 timer_resolution 指令指定的时间设置一个定时器
*/
if (ngx_timer_resolution && !(ngx_event_flags & NGX_USE_TIMER_EVENT)) {
struct sigaction sa;
struct itimerval itv;
ngx_memzero(&sa, sizeof(struct sigaction));
sa.sa_handler = ngx_timer_signal_handler;
sigemptyset(&sa.sa_mask);
if (sigaction(SIGALRM, &sa, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"sigaction(SIGALRM) failed");
return NGX_ERROR;
}
itv.it_interval.tv_sec = ngx_timer_resolution / 1000;
itv.it_interval.tv_usec = (ngx_timer_resolution % 1000) * 1000;
itv.it_value.tv_sec = ngx_timer_resolution / 1000;
itv.it_value.tv_usec = (ngx_timer_resolution % 1000 ) * 1000;
if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"setitimer() failed");
}
}
if (ngx_event_flags & NGX_USE_FD_EVENT) { /* [analy] epoll模块不使用 */
struct rlimit rlmt;
if (getrlimit(RLIMIT_NOFILE, &rlmt) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"getrlimit(RLIMIT_NOFILE) failed");
return NGX_ERROR;
}
cycle->files_n = (ngx_uint_t) rlmt.rlim_cur;
cycle->files = ngx_calloc(sizeof(ngx_connection_t *) * cycle->files_n,
cycle->log);
if (cycle->files == NULL) {
return NGX_ERROR;
}
}
#endif
/* [analy] 为连接池申请空间，由于此处在worker进程初始化时进行的，所以
每个worker都会拥有一个自己的connections连接池
根据配置worker_connections指令指定的个数申请 */
cycle->connections =
ngx_alloc(sizeof(ngx_connection_t) * cycle->connection_n, cycle->log);
if (cycle->connections == NULL) {
return NGX_ERROR;
}
c = cycle->connections;
/* [analy] 为读事件队列申请空间 */
cycle->read_events = ngx_alloc(sizeof(ngx_event_t) * cycle->connection_n,
cycle->log);
if (cycle->read_events == NULL) {
return NGX_ERROR;
}
rev = cycle->read_events;
for (i = 0; i < cycle->connection_n; i++) {
rev[i].closed = 1;
rev[i].instance = 1;
#if (NGX_THREADS)
rev[i].lock = &c[i].lock;
rev[i].own_lock = &c[i].lock;
#endif
}
/* [analy] 为写事件队列申请空间 */
cycle->write_events = ngx_alloc(sizeof(ngx_event_t) * cycle->connection_n,
cycle->log);
if (cycle->write_events == NULL) {
return NGX_ERROR;
}
wev = cycle->write_events;
for (i = 0; i < cycle->connection_n; i++) {
wev[i].closed = 1;
#if (NGX_THREADS)
wev[i].lock = &c[i].lock;
wev[i].own_lock = &c[i].lock;
#endif
}
/* [analy] 初始化connections数组
data字段指向下一个元素
read事件指针指向read_events对应下标的元素
write事件指针指向write_events对应下标的元素
fd初始化-1
*/
i = cycle->connection_n;
next = NULL;
do {
i--;
c[i].data = next;
c[i].read = &cycle->read_events[i]; /* [analy] 将连接池中connections的read事件与read_events数组中的对应下标的元素关联 */
c[i].write = &cycle->write_events[i]; /* [analy] 将连接池中connections的write事件与write_events数组中对应下标元素关联 */
c[i].fd = (ngx_socket_t) -1;
next = &c[i];
#if (NGX_THREADS)
c[i].lock = 0;
#endif
} while (i);
/* 初始化free_connections空闲连接池和空闲连接个数;指向connections连接池首地址 */
cycle->free_connections = next;
cycle->free_connection_n = cycle->connection_n;
/* [analy] 为每一个套接口分配一个空闲的连接 */
/* for each listening socket */
ls = cycle->listening.elts;
for (i = 0; i < cycle->listening.nelts; i++) {
c = ngx_get_connection(ls[i].fd, cycle->log);
if (c == NULL) {
return NGX_ERROR;
}
c->log = &ls[i].log;
c->listening = &ls[i]; /* [analy] connection的listening指针指向cycle->listening[n] */
ls[i].connection = c; /* [analy] cycle->listening[n]->connection指针指向了申请的空闲connection */
rev = c->read;
rev->log = c->log;
rev->accept = 1; // 设置监听套接字标识
#if (NGX_HAVE_DEFERRED_ACCEPT)
rev->deferred_accept = ls[i].deferred_accept;
#endif
if (!(ngx_event_flags & NGX_USE_IOCP_EVENT)) {
if (ls[i].previous) {
/*
* delete the old accept events that were bound to
* the old cycle read events array
*/
old = ls[i].previous->connection;
if (ngx_del_event(old->read, NGX_READ_EVENT, NGX_CLOSE_EVENT)
== NGX_ERROR)
{
return NGX_ERROR;
}
old->fd = (ngx_socket_t) -1;
}
}
#if (NGX_WIN32)
if (ngx_event_flags & NGX_USE_IOCP_EVENT) {
ngx_iocp_conf_t *iocpcf;
rev->handler = ngx_event_acceptex;
if (ngx_use_accept_mutex) {
continue;
}
if (ngx_add_event(rev, 0, NGX_IOCP_ACCEPT) == NGX_ERROR) {
return NGX_ERROR;
}
ls[i].log.handler = ngx_acceptex_log_error;
iocpcf = ngx_event_get_conf(cycle->conf_ctx, ngx_iocp_module);
if (ngx_event_post_acceptex(&ls[i], iocpcf->post_acceptex)
== NGX_ERROR)
{
return NGX_ERROR;
}
} else {
rev->handler = ngx_event_accept;
if (ngx_use_accept_mutex) {
continue;
}
if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
}
#else
rev->handler = ngx_event_accept; /* [analy] 设置accpet回调处理函数 */
if (ngx_use_accept_mutex) {
continue;
}
if (ngx_event_flags & NGX_USE_RTSIG_EVENT) {
if (ngx_add_conn(c) == NGX_ERROR) {
return NGX_ERROR;
}
} else {
if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) { /* [analy] 将event送进epoll队列中 */
return NGX_ERROR;
}
}
#endif
}
return NGX_OK;
}
ngx_int_t
ngx_handle_write_event(ngx_event_t *wev, size_t lowat)
{
ngx_connection_t *c;
if (lowat) {
c = wev->data;
if (ngx_send_lowat(c, lowat) == NGX_ERROR) {
return NGX_ERROR;
}
}
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
/* kqueue, epoll */
if (!wev->active && !wev->ready) {
if (ngx_add_event(wev, NGX_WRITE_EVENT,
NGX_CLEAR_EVENT | (lowat ? NGX_LOWAT_EVENT : 0))
== NGX_ERROR)
{
return NGX_ERROR;
}
}
return NGX_OK;
} else if (ngx_event_flags & NGX_USE_LEVEL_EVENT) {
/* select, poll, /dev/poll */
if (!wev->active && !wev->ready) {
if (ngx_add_event(wev, NGX_WRITE_EVENT, NGX_LEVEL_EVENT)
== NGX_ERROR)
{
return NGX_ERROR;
}
return NGX_OK;
}
if (wev->active && wev->ready) {
if (ngx_del_event(wev, NGX_WRITE_EVENT, NGX_LEVEL_EVENT)
== NGX_ERROR)
{
return NGX_ERROR;
}
return NGX_OK;
}
} else if (ngx_event_flags & NGX_USE_EVENTPORT_EVENT) {
/* event ports */
if (!wev->active && !wev->ready) {
if (ngx_add_event(wev, NGX_WRITE_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
if (wev->oneshot && wev->ready) {
if (ngx_del_event(wev, NGX_WRITE_EVENT, 0) == NGX_ERROR) {
return NGX_ERROR;
}
return NGX_OK;
}
}
/* aio, iocp, rtsig */
return NGX_OK;
}
ngx_int_t
ngx_event_connect_peer(ngx_peer_connection_t *pc)
{ //Here,we initilize a connection!!!
int rc;
ngx_int_t event;
ngx_err_t err;
ngx_uint_t level;
ngx_socket_t s;
ngx_event_t *rev, *wev;
ngx_connection_t *c;
//Here,very important, this handler is use to get a select handler!!
/*
For ip_hash module,will set the get handler!!!
r->upstream->peer.get = ngx_http_upstream_get_round_robin_peer;
r->upstream->peer.free = ngx_http_upstream_free_round_robin_peer;
*/
//will stored the really backend ip_addr in the pc!!
rc = pc->get(pc, pc->data);
if (rc != NGX_OK) {
return rc;
}
//Here,Do the socket operation! alloc a socket_fd
s = ngx_socket(pc->sockaddr->sa_family, SOCK_STREAM, 0);
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, pc->log, 0, "socket %d", s);
if (s == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_socket_n " failed");
return NGX_ERROR;
}
c = ngx_get_connection(s, pc->log);
if (c == NULL) {
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_close_socket_n "failed");
}
return NGX_ERROR;
}
if (pc->rcvbuf) {
if (setsockopt(s, SOL_SOCKET, SO_RCVBUF,
(const void *) &pc->rcvbuf, sizeof(int)) == -1)
{
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
"setsockopt(SO_RCVBUF) failed");
goto failed;
}
}
if (ngx_nonblocking(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_nonblocking_n " failed");
goto failed;
}
if (pc->local) {
if (bind(s, pc->local->sockaddr, pc->local->socklen) == -1) {
ngx_log_error(NGX_LOG_CRIT, pc->log, ngx_socket_errno,
"bind(%V) failed", &pc->local->name);
goto failed;
}
}
//########################### Here set the connection data's read write handler!!!
c->recv = ngx_recv;
c->send = ngx_send;
c->recv_chain = ngx_recv_chain;
c->send_chain = ngx_send_chain;
c->sendfile = 1;
c->log_error = pc->log_error;
if (pc->sockaddr->sa_family != AF_INET) {
c->tcp_nopush = NGX_TCP_NOPUSH_DISABLED;
c->tcp_nodelay = NGX_TCP_NODELAY_DISABLED;
#if (NGX_SOLARIS)
/* Solaris's sendfilev() supports AF_NCA, AF_INET, and AF_INET6 */
c->sendfile = 0;
#endif
}
rev = c->read;
wev = c->write;
rev->log = pc->log;
wev->log = pc->log;
pc->connection = c;
c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
#if (NGX_THREADS)
/* TODO: lock event when call completion handler */
rev->lock = pc->lock;
wev->lock = pc->lock;
rev->own_lock = &c->lock;
wev->own_lock = &c->lock;
#endif
if (ngx_add_conn) {
if (ngx_add_conn(c) == NGX_ERROR) {
goto failed;
}
}
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, pc->log, 0,
"connect to %V, fd:%d #%d", pc->name, s, c->number);
//########################## Here,doing the really connect operation
rc = connect(s, pc->sockaddr, pc->socklen);
if (rc == -1) {
err = ngx_socket_errno;
if (err != NGX_EINPROGRESS
#if (NGX_WIN32)
/* Winsock returns WSAEWOULDBLOCK (NGX_EAGAIN) */
&& err != NGX_EAGAIN
#endif
)
{
if (err == NGX_ECONNREFUSED
#if (NGX_LINUX)
/*
* Linux returns EAGAIN instead of ECONNREFUSED
* for unix sockets if listen queue is full
*/
|| err == NGX_EAGAIN
#endif
|| err == NGX_ECONNRESET
|| err == NGX_ENETDOWN
|| err == NGX_ENETUNREACH
|| err == NGX_EHOSTDOWN
|| err == NGX_EHOSTUNREACH)
{
level = NGX_LOG_ERR;
} else {
level = NGX_LOG_CRIT;
}
ngx_log_error(level, c->log, err, "connect() to %V failed",
pc->name);
return NGX_DECLINED;
}
}
if (ngx_add_conn) {
if (rc == -1) {
/* NGX_EINPROGRESS */
return NGX_AGAIN;
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected");
wev->ready = 1;//
return NGX_OK;
}
if (ngx_event_flags & NGX_USE_AIO_EVENT) {
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, pc->log, ngx_socket_errno,
"connect(): %d", rc);
/* aio, iocp */
if (ngx_blocking(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_blocking_n " failed");
goto failed;
}
/*
* FreeBSD's aio allows to post an operation on non-connected socket.
* NT does not support it.
*
* TODO: check in Win32, etc. As workaround we can use NGX_ONESHOT_EVENT
*/
rev->ready = 1;
wev->ready = 1;
return NGX_OK;
}
if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {
/* kqueue */
event = NGX_CLEAR_EVENT;
} else {
/* select, poll, /dev/poll */
event = NGX_LEVEL_EVENT;
}
//##########################################Very important!
//##########################################add the connection read event!!
if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) {
goto failed;
}
if (rc == -1) {
/* NGX_EINPROGRESS */
if (ngx_add_event(wev, NGX_WRITE_EVENT, event) != NGX_OK) {
goto failed;
}
return NGX_AGAIN;
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected");
wev->ready = 1; //Means the connection is ready to write!
return NGX_OK;
failed:
ngx_free_connection(c);
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
ngx_close_socket_n " failed");
}
return NGX_ERROR;
}