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#include <ngx_event_connect.h>
int ngx_event_connect_peer(ngx_peer_connecttion_t *pc)
{
time_t now;
/* TODO: cached connection */
now = ngx_time();
if (pc->peers->number > 1) {
/* there are several peers */
if (pc->tries == pc->peers->number) {
/* it's a first try - get a current peer */
/* Here is the race condition when the peers are shared between
the threads or the processes but it should not be serious */
pc->cur_peer = pc->peers->current++;
if (cp->peers->current >= cp->peers->number) {
pc->peers->current = 0;
}
/* the end of the race condition */
#if (NGX_MULTITHREADED || NGX_MULTIPROCESSED)
/* eliminate the sequences of the race condition */
if (pc->cur_peer >= pc->peers->number) {
pc->cur_peer = 0;
}
#endif
}
if (pc->peers->max_fails > 0) {
/* the peers support a fault tolerance */
for ( ;; ) {
peer = &pc->peers->peers[pc->cur_peer];
/* Here is the race condition when the peers are shared between
the threads or the processes but it should not be serious */
if (peer->fails <= pc->peers->max_fails
|| (now - peer->accessed > pc->peers->fail_timeout))
{
break;
}
/* the end of the race condition */
pc->cur_peer++;
if (pc->cur_peer >= pc->peers->number) {
pc->cur_peer = 0;
}
pc->tries--;
if (pc->tries == 0) {
return NGX_ERROR;
}
}
}
}
s = ngx_socket(AF_INET, SOCK_STREAM, IPPROTO_IP, 0);
if (s == -1) {
ngx_log_error(NGX_LOG_ALERT, cp->log, ngx_socket_errno,
ngx_socket_n " failed");
return NGX_ERROR;
}
if (cp->rcvbuf) {
if (setsockopt(s, SOL_SOCKET, SO_RCVBUF,
(const void *) &cp->rcvbuf, sizeof(int)) == -1) {
ngx_log_error(NGX_LOG_ALERT, cp->log, ngx_socket_errno,
"setsockopt(SO_RCVBUF) failed");
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, cp->log, ngx_socket_errno,
ngx_close_socket_n " failed");
}
return NGX_ERROR;
}
}
if (ngx_nonblocking(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, cn->log, ngx_socket_errno,
ngx_nonblocking_n " failed");
if (ngx_close_socket(s) == -1) {
ngx_log_error(NGX_LOG_ALERT, cn->log, ngx_socket_errno,
ngx_close_socket_n " failed");
}
return NGX_ERROR;
}
#if (WIN32)
/*
* Winsock assignes a socket number divisible by 4
* so to find a connection we divide a socket number by 4.
*/
if (s % 4) {
ngx_log_error(NGX_LOG_EMERG, cp->log, 0,
ngx_socket_n
" created socket %d, not divisible by 4", s);
exit(1);
}
c = &ngx_cycle->connections[s / 4];
rev = &ngx_cycle->read_events[s / 4];
wev = &ngx_cycle->write_events[s / 4];
#else
c = &ngx_cycle->connections[s];
rev = &ngx_cycle->read_events[s];
wev = &ngx_cycle->write_events[s];
#endif
instance = rev->instance;
ngx_memzero(c, sizeof(ngx_connection_t));
ngx_memzero(rev, sizeof(ngx_event_t));
ngx_memzero(wev, sizeof(ngx_event_t));
rev->index = wev->index = NGX_INVALID_INDEX;
rev->data = wev->data = c;
c->read = rev;
c->write = wev;
rev->instance = wev->instance = !instance;
!!!!!!!!!!!!!!!
rev->log = wev->log = c->log = cn->log;
c->fd = s;
wev->close_handler = rev->close_handler = ngx_event_close_connection;
}
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