/* Update polling on connection <c>'s file descriptor depending on its current
* state as reported in the connection's CO_FL_CURR_* flags, reports of EAGAIN
* in CO_FL_WAIT_*, and the sock layer expectations indicated by CO_FL_SOCK_*.
* The connection flags are updated with the new flags at the end of the
* operation.
*/
void conn_update_sock_polling(struct connection *c)
{
unsigned int f = c->flags;
/* update read status if needed */
if (unlikely((f & (CO_FL_CURR_RD_ENA|CO_FL_SOCK_RD_ENA)) == CO_FL_CURR_RD_ENA)) {
f &= ~(CO_FL_CURR_RD_ENA|CO_FL_CURR_RD_POL);
fd_stop_recv(c->t.sock.fd);
}
else if (unlikely((f & (CO_FL_CURR_RD_ENA|CO_FL_CURR_RD_POL)) != (CO_FL_CURR_RD_ENA|CO_FL_CURR_RD_POL) &&
(f & (CO_FL_SOCK_RD_ENA|CO_FL_WAIT_RD)) == (CO_FL_SOCK_RD_ENA|CO_FL_WAIT_RD))) {
f |= (CO_FL_CURR_RD_ENA|CO_FL_CURR_RD_POL);
fd_poll_recv(c->t.sock.fd);
}
else if (unlikely((f & (CO_FL_CURR_RD_ENA|CO_FL_SOCK_RD_ENA)) == CO_FL_SOCK_RD_ENA)) {
f |= CO_FL_CURR_RD_ENA;
fd_want_recv(c->t.sock.fd);
}
/* update write status if needed */
if (unlikely((f & (CO_FL_CURR_WR_ENA|CO_FL_SOCK_WR_ENA)) == CO_FL_CURR_WR_ENA)) {
f &= ~(CO_FL_CURR_WR_ENA|CO_FL_CURR_WR_POL);
fd_stop_send(c->t.sock.fd);
}
else if (unlikely((f & (CO_FL_CURR_WR_ENA|CO_FL_CURR_WR_POL)) != (CO_FL_CURR_WR_ENA|CO_FL_CURR_WR_POL) &&
(f & (CO_FL_SOCK_WR_ENA|CO_FL_WAIT_WR)) == (CO_FL_SOCK_WR_ENA|CO_FL_WAIT_WR))) {
f |= (CO_FL_CURR_WR_ENA|CO_FL_CURR_WR_POL);
fd_poll_send(c->t.sock.fd);
}
else if (unlikely((f & (CO_FL_CURR_WR_ENA|CO_FL_SOCK_WR_ENA)) == CO_FL_SOCK_WR_ENA)) {
f |= CO_FL_CURR_WR_ENA;
fd_want_send(c->t.sock.fd);
}
c->flags = f;
}
/* Update polling on connection <c>'s file descriptor depending on its current
* state as reported in the connection's CO_FL_CURR_* flags, reports of EAGAIN
* in CO_FL_WAIT_*, and the sock layer expectations indicated by CO_FL_SOCK_*.
* The connection flags are updated with the new flags at the end of the
* operation. Polling is totally disabled if an error was reported.
*/
void conn_update_sock_polling(struct connection *c)
{
unsigned int f = c->flags;
if (!conn_ctrl_ready(c))
return;
/* update read status if needed */
if (unlikely((f & (CO_FL_CURR_RD_ENA|CO_FL_SOCK_RD_ENA)) == CO_FL_SOCK_RD_ENA)) {
fd_want_recv(c->t.sock.fd);
f |= CO_FL_CURR_RD_ENA;
}
else if (unlikely((f & (CO_FL_CURR_RD_ENA|CO_FL_SOCK_RD_ENA)) == CO_FL_CURR_RD_ENA)) {
fd_stop_recv(c->t.sock.fd);
f &= ~CO_FL_CURR_RD_ENA;
}
/* update write status if needed */
if (unlikely((f & (CO_FL_CURR_WR_ENA|CO_FL_SOCK_WR_ENA)) == CO_FL_SOCK_WR_ENA)) {
fd_want_send(c->t.sock.fd);
f |= CO_FL_CURR_WR_ENA;
}
else if (unlikely((f & (CO_FL_CURR_WR_ENA|CO_FL_SOCK_WR_ENA)) == CO_FL_CURR_WR_ENA)) {
fd_stop_send(c->t.sock.fd);
f &= ~CO_FL_CURR_WR_ENA;
}
c->flags = f;
}
/* Marks a ready listener as limited so that we only try to re-enable it when
* resources are free again. It will be queued into the specified queue.
*/
void limit_listener(struct listener *l, struct list *list)
{
if (l->state == LI_READY) {
LIST_ADDQ(list, &l->wait_queue);
fd_stop_recv(l->fd);
l->state = LI_LIMITED;
}
}
/* This function removes the specified listener's file descriptor from the
* polling lists if it is in the LI_READY or in the LI_FULL state. The listener
* enters LI_LISTEN.
*/
void disable_listener(struct listener *listener)
{
if (listener->state < LI_READY)
return;
if (listener->state == LI_READY)
fd_stop_recv(listener->fd);
if (listener->state == LI_LIMITED)
LIST_DEL(&listener->wait_queue);
listener->state = LI_LISTEN;
}
/* Marks a ready listener as full so that the session code tries to re-enable
* it upon next close() using resume_listener().
*/
void listener_full(struct listener *l)
{
if (l->state >= LI_READY) {
if (l->state == LI_LIMITED)
LIST_DEL(&l->wait_queue);
fd_stop_recv(l->fd);
l->state = LI_FULL;
}
}
/* This function adds the specified listener's file descriptor to the polling
* lists if it is in the LI_LISTEN state. The listener enters LI_READY or
* LI_FULL state depending on its number of connections. In deamon mode, we
* also support binding only the relevant processes to their respective
* listeners. We don't do that in debug mode however.
*/
void enable_listener(struct listener *listener)
{
if (listener->state == LI_LISTEN) {
if ((global.mode & (MODE_DAEMON | MODE_SYSTEMD)) &&
listener->bind_conf->bind_proc &&
!(listener->bind_conf->bind_proc & (1UL << (relative_pid - 1)))) {
/* we don't want to enable this listener and don't
* want any fd event to reach it.
*/
fd_stop_recv(listener->fd);
listener->state = LI_PAUSED;
}
else if (listener->nbconn < listener->maxconn) {
fd_want_recv(listener->fd);
listener->state = LI_READY;
}
else {
listener->state = LI_FULL;
}
}
}
/* This function tries to temporarily disable a listener, depending on the OS
* capabilities. Linux unbinds the listen socket after a SHUT_RD, and ignores
* SHUT_WR. Solaris refuses either shutdown(). OpenBSD ignores SHUT_RD but
* closes upon SHUT_WR and refuses to rebind. So a common validation path
* involves SHUT_WR && listen && SHUT_RD. In case of success, the FD's polling
* is disabled. It normally returns non-zero, unless an error is reported.
*/
int pause_listener(struct listener *l)
{
if (l->state <= LI_PAUSED)
return 1;
if (shutdown(l->fd, SHUT_WR) != 0)
return 0; /* Solaris dies here */
if (listen(l->fd, l->backlog ? l->backlog : l->maxconn) != 0)
return 0; /* OpenBSD dies here */
if (shutdown(l->fd, SHUT_RD) != 0)
return 0; /* should always be OK */
if (l->state == LI_LIMITED)
LIST_DEL(&l->wait_queue);
fd_stop_recv(l->fd);
l->state = LI_PAUSED;
return 1;
}
/* This function tries to temporarily disable a listener, depending on the OS
* capabilities. Linux unbinds the listen socket after a SHUT_RD, and ignores
* SHUT_WR. Solaris refuses either shutdown(). OpenBSD ignores SHUT_RD but
* closes upon SHUT_WR and refuses to rebind. So a common validation path
* involves SHUT_WR && listen && SHUT_RD. In case of success, the FD's polling
* is disabled. It normally returns non-zero, unless an error is reported.
*/
int pause_listener(struct listener *l)
{
if (l->state <= LI_PAUSED)
return 1;
if (l->proto->pause) {
/* Returns < 0 in case of failure, 0 if the listener
* was totally stopped, or > 0 if correctly paused.
*/
int ret = l->proto->pause(l);
if (ret < 0)
return 0;
else if (ret == 0)
return 1;
}
if (l->state == LI_LIMITED)
LIST_DEL(&l->wait_queue);
fd_stop_recv(l->fd);
l->state = LI_PAUSED;
return 1;
}
