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#include <ngx_event_connect.h>
int ngx_event_connect_peer(ngx_connect_peer_t *cp)
{
if (cp->peers->number > 1) {
/* it's a first try - get current peer */
if (cp->tries == cp->peers->number) {
/* Here is the race condition
when the peers are shared between
the threads or the processes but it should not be serious */
cp->cur_peer = cp->peers->current++;
if (cp->peers->current >= cp->peers->number) {
cp->peers->current = 0;
}
/* */
#if (NGX_MULTITHREADED || NGX_MULTIPROCESSED)
/* eliminate the sequences of the race condition */
if (cp->cur_peer >= cp->peers->number) {
cp->cur_peer = 0;
}
#endif
}
if (cp->peers->max_fails > 0) {
for ( ;; ) {
peer = &cp->peers->peers[cp->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 <= cp->peers->max_fails
|| (now - peer->accessed > cp->peers->fail_timeout))
{
break;
}
/* */
cp->cur_peer++;
if (cp->cur_peer >= cp->peers->number) {
cp->cur_peer = 0;
}
cp->tries--;
if (cp->tries == 0) {
return NGX_ERROR;
}
}
}
}
s = ngx_socket(AF_INET, SOCK_STREAM, IPPROTO_IP, 0);
if (s == -1) {
ngx_log_error(NGX_LOG_ALERT, cn->log, ngx_socket_errno,
ngx_socket_n " failed");
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
if (cn->rcvbuf) {
if (setsockopt(s, SOL_SOCKET, SO_RCVBUF,
(const void *) &cn->rcvbuf, sizeof(int)) == -1) {
ngx_log_error(NGX_LOG_ALERT, cn->log, ngx_socket_errno,
"setsockopt(SO_RCVBUF) 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_HTTP_INTERNAL_SERVER_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_HTTP_INTERNAL_SERVER_ERROR;
}
c = &ngx_connections[s];
rev = &ngx_read_events[s];
wev = &ngx_write_events[s];
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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