/* This function removes all of the protocol's listener's file descriptors from
* the polling lists when they are in the LI_READY or LI_FULL states. It is
* intended to be used as a protocol's generic disable_all() primitive. It puts
* the listeners into LI_LISTEN, and always returns ERR_NONE.
*/
int disable_all_listeners(struct protocol *proto)
{
struct listener *listener;
list_for_each_entry(listener, &proto->listeners, proto_list)
disable_listener(listener);
return ERR_NONE;
}
/*
* this function enables proxies when there are enough free sessions,
* or stops them when the table is full. It is designed to be called from the
* select_loop(). It adjusts the date of next expiration event during stop
* time if appropriate.
*/
void maintain_proxies(int *next)
{
struct proxy *p;
struct listener *l;
unsigned int wait;
p = proxy;
/* if there are enough free sessions, we'll activate proxies */
if (actconn < global.maxconn) {
for (; p; p = p->next) {
/* check the various reasons we may find to block the frontend */
if (p->feconn >= p->maxconn)
goto do_block;
if (p->fe_sps_lim &&
(wait = next_event_delay(&p->fe_sess_per_sec, p->fe_sps_lim, 1))) {
/* we're blocking because a limit was reached on the number of
* requests/s on the frontend. We want to re-check ASAP, which
* means in 1 ms before estimated expiration date, because the
* timer will have settled down. Note that we may already be in
* IDLE state here.
*/
*next = tick_first(*next, tick_add(now_ms, wait));
goto do_block;
}
/* OK we have no reason to block, so let's unblock if we were blocking */
if (p->state == PR_STIDLE) {
for (l = p->listen; l != NULL; l = l->next)
enable_listener(l);
p->state = PR_STRUN;
}
continue;
do_block:
if (p->state == PR_STRUN) {
for (l = p->listen; l != NULL; l = l->next)
disable_listener(l);
p->state = PR_STIDLE;
}
}
}
else { /* block all proxies */
while (p) {
if (p->state == PR_STRUN) {
for (l = p->listen; l != NULL; l = l->next)
disable_listener(l);
p->state = PR_STIDLE;
}
p = p->next;
}
}
if (stopping) {
p = proxy;
while (p) {
if (p->state != PR_STSTOPPED) {
int t;
t = tick_remain(now_ms, p->stop_time);
if (t == 0) {
Warning("Proxy %s stopped (FE: %lld conns, BE: %lld conns).\n",
p->id, p->cum_feconn, p->cum_beconn);
send_log(p, LOG_WARNING, "Proxy %s stopped (FE: %lld conns, BE: %lld conns).\n",
p->id, p->cum_feconn, p->cum_beconn);
stop_proxy(p);
/* try to free more memory */
pool_gc2();
}
else {
*next = tick_first(*next, p->stop_time);
}
}
p = p->next;
}
}
return;
}
/* This function is called on a read event from a listening socket, corresponding
* to an accept. It tries to accept as many connections as possible, and for each
* calls the listener's accept handler (generally the frontend's accept handler).
*/
int stream_sock_accept(int fd)
{
struct listener *l = fdtab[fd].owner;
struct proxy *p = l->frontend;
int max_accept = global.tune.maxaccept;
int cfd;
int ret;
if (unlikely(l->nbconn >= l->maxconn)) {
EV_FD_CLR(l->fd, DIR_RD);
l->state = LI_FULL;
return 0;
}
if (p && p->fe_sps_lim) {
int max = freq_ctr_remain(&p->fe_sess_per_sec, p->fe_sps_lim, 0);
if (max_accept > max)
max_accept = max;
}
while ((!p || p->feconn < p->maxconn) && actconn < global.maxconn && max_accept--) {
struct sockaddr_storage addr;
socklen_t laddr = sizeof(addr);
cfd = accept(fd, (struct sockaddr *)&addr, &laddr);
if (unlikely(cfd == -1)) {
switch (errno) {
case EAGAIN:
case EINTR:
case ECONNABORTED:
return 0; /* nothing more to accept */
case ENFILE:
if (p)
send_log(p, LOG_EMERG,
"Proxy %s reached system FD limit at %d. Please check system tunables.\n",
p->id, maxfd);
return 0;
case EMFILE:
if (p)
send_log(p, LOG_EMERG,
"Proxy %s reached process FD limit at %d. Please check 'ulimit-n' and restart.\n",
p->id, maxfd);
return 0;
case ENOBUFS:
case ENOMEM:
if (p)
send_log(p, LOG_EMERG,
"Proxy %s reached system memory limit at %d sockets. Please check system tunables.\n",
p->id, maxfd);
return 0;
default:
return 0;
}
}
if (unlikely(cfd >= global.maxsock)) {
send_log(p, LOG_EMERG,
"Proxy %s reached the configured maximum connection limit. Please check the global 'maxconn' value.\n",
p->id);
close(cfd);
return 0;
}
jobs++;
actconn++;
totalconn++;
l->nbconn++;
if (l->counters) {
if (l->nbconn > l->counters->conn_max)
l->counters->conn_max = l->nbconn;
}
ret = l->accept(l, cfd, &addr);
if (unlikely(ret <= 0)) {
/* The connection was closed by session_accept(). Either
* we just have to ignore it (ret == 0) or it's a critical
* error due to a resource shortage, and we must stop the
* listener (ret < 0).
*/
jobs--;
actconn--;
l->nbconn--;
if (ret == 0) /* successful termination */
continue;
if (p) {
disable_listener(l);
p->state = PR_STIDLE;
}
return 0;
}
if (l->nbconn >= l->maxconn) {
EV_FD_CLR(l->fd, DIR_RD);
l->state = LI_FULL;
}
} /* end of while (p->feconn < p->maxconn) */
return 0;
}
