Use poll() instead of select() to remove limits on open file descriptors.
diff --git a/src/dnsmasq.c b/src/dnsmasq.c
index fd24f63..514e10b 100644
--- a/src/dnsmasq.c
+++ b/src/dnsmasq.c
@@ -24,8 +24,8 @@
static volatile pid_t pid = 0;
static volatile int pipewrite;
-static int set_dns_listeners(time_t now, fd_set *set, int *maxfdp);
-static void check_dns_listeners(fd_set *set, time_t now);
+static int set_dns_listeners(time_t now);
+static void check_dns_listeners(time_t now);
static void sig_handler(int sig);
static void async_event(int pipe, time_t now);
static void fatal_event(struct event_desc *ev, char *msg);
@@ -799,10 +799,6 @@
if (option_bool(OPT_TFTP))
{
struct tftp_prefix *p;
-#ifdef FD_SETSIZE
- if (FD_SETSIZE < (unsigned)max_fd)
- max_fd = FD_SETSIZE;
-#endif
my_syslog(MS_TFTP | LOG_INFO, "TFTP %s%s %s",
daemon->tftp_prefix ? _("root is ") : _("enabled"),
@@ -862,72 +858,58 @@
while (1)
{
- int maxfd = -1;
- struct timeval t, *tp = NULL;
- fd_set rset, wset, eset;
+ int t, timeout = -1;
- FD_ZERO(&rset);
- FD_ZERO(&wset);
- FD_ZERO(&eset);
+ poll_reset();
/* if we are out of resources, find how long we have to wait
for some to come free, we'll loop around then and restart
listening for queries */
- if ((t.tv_sec = set_dns_listeners(now, &rset, &maxfd)) != 0)
- {
- t.tv_usec = 0;
- tp = &t;
- }
+ if ((t = set_dns_listeners(now)) != 0)
+ timeout = t * 1000;
/* Whilst polling for the dbus, or doing a tftp transfer, wake every quarter second */
if (daemon->tftp_trans ||
(option_bool(OPT_DBUS) && !daemon->dbus))
- {
- t.tv_sec = 0;
- t.tv_usec = 250000;
- tp = &t;
- }
+ timeout = 250;
+
/* Wake every second whilst waiting for DAD to complete */
else if (is_dad_listeners())
- {
- t.tv_sec = 1;
- t.tv_usec = 0;
- tp = &t;
- }
+ timeout = 1000;
#ifdef HAVE_DBUS
- set_dbus_listeners(&maxfd, &rset, &wset, &eset);
+ set_dbus_listeners();
#endif
#ifdef HAVE_DHCP
if (daemon->dhcp || daemon->relay4)
{
- bump_maxfd(&rset, daemon->dhcpfd, &maxfd);
+ poll_listen(daemon->dhcpfd, POLLIN);
if (daemon->pxefd != -1)
- bump_maxfd(&rset, daemon->pxefd, &maxfd);
+ poll_listen(daemon->pxefd, POLLIN);
}
#endif
#ifdef HAVE_DHCP6
if (daemon->doing_dhcp6 || daemon->relay6)
- bump_maxfd(&rset, daemon->dhcp6fd, &maxfd);
+ poll_listen(daemon->dhcp6fd, POLLIN);
if (daemon->doing_ra)
- bump_maxfd(&rset, daemon->icmp6fd, &maxfd);
+ poll_listen(daemon->icmp6fd, POLLIN);
#endif
#ifdef HAVE_INOTIFY
if (daemon->inotifyfd != -1)
- bump_maxfd(&rset, daemon->inotifyfd, &maxfd);
+ poll_listen(daemon->inotifyfd, POLLIN);
#endif
#if defined(HAVE_LINUX_NETWORK)
- bump_maxfd(&rset, daemon->netlinkfd, &maxfd);
+ poll_listen(daemon->netlinkfd, POLLIN);
#elif defined(HAVE_BSD_NETWORK)
- bump_maxfd(&rset, daemon->routefd, &maxfd);
+ poll_listen(daemon->routefd, POLLIN);
#endif
- bump_maxfd(&rset, piperead, &maxfd);
+ poll_listen(piperead, POLLIN);
#ifdef HAVE_DHCP
# ifdef HAVE_SCRIPT
@@ -938,7 +920,7 @@
# endif
if (!helper_buf_empty())
- bump_maxfd(&wset, daemon->helperfd, &maxfd);
+ poll_listen(daemon->helperfd, POLLOUT);
# else
/* need this for other side-effects */
while (do_script_run(now));
@@ -952,17 +934,14 @@
/* must do this just before select(), when we know no
more calls to my_syslog() can occur */
- set_log_writer(&wset, &maxfd);
+ set_log_writer();
- if (select(maxfd+1, &rset, &wset, &eset, tp) < 0)
- {
- /* otherwise undefined after error */
- FD_ZERO(&rset); FD_ZERO(&wset); FD_ZERO(&eset);
- }
-
+ if (do_poll(timeout) < 0)
+ continue;
+
now = dnsmasq_time();
- check_log_writer(&wset);
+ check_log_writer(0);
/* prime. */
enumerate_interfaces(1);
@@ -978,15 +957,15 @@
}
#if defined(HAVE_LINUX_NETWORK)
- if (FD_ISSET(daemon->netlinkfd, &rset))
+ if (poll_check(daemon->netlinkfd, POLLIN))
netlink_multicast();
#elif defined(HAVE_BSD_NETWORK)
- if (FD_ISSET(daemon->routefd, &rset))
+ if (poll_check(daemon->routefd, POLLIN))
route_sock();
#endif
#ifdef HAVE_INOTIFY
- if (daemon->inotifyfd != -1 && FD_ISSET(daemon->inotifyfd, &rset) && inotify_check(now))
+ if (daemon->inotifyfd != -1 && poll_check(daemon->inotifyfd, POLLIN) && inotify_check(now))
{
if (daemon->port != 0 && !option_bool(OPT_NO_POLL))
poll_resolv(1, 1, now);
@@ -1006,7 +985,7 @@
}
#endif
- if (FD_ISSET(piperead, &rset))
+ if (poll_check(piperead, POLLIN))
async_event(piperead, now);
#ifdef HAVE_DBUS
@@ -1019,34 +998,34 @@
if (daemon->dbus)
my_syslog(LOG_INFO, _("connected to system DBus"));
}
- check_dbus_listeners(&rset, &wset, &eset);
+ check_dbus_listeners();
#endif
- check_dns_listeners(&rset, now);
+ check_dns_listeners(now);
#ifdef HAVE_TFTP
- check_tftp_listeners(&rset, now);
+ check_tftp_listeners(now);
#endif
#ifdef HAVE_DHCP
if (daemon->dhcp || daemon->relay4)
{
- if (FD_ISSET(daemon->dhcpfd, &rset))
+ if (poll_check(daemon->dhcpfd, POLLIN))
dhcp_packet(now, 0);
- if (daemon->pxefd != -1 && FD_ISSET(daemon->pxefd, &rset))
+ if (daemon->pxefd != -1 && poll_check(daemon->pxefd, POLLIN))
dhcp_packet(now, 1);
}
#ifdef HAVE_DHCP6
- if ((daemon->doing_dhcp6 || daemon->relay6) && FD_ISSET(daemon->dhcp6fd, &rset))
+ if ((daemon->doing_dhcp6 || daemon->relay6) && poll_check(daemon->dhcp6fd, POLLIN))
dhcp6_packet(now);
- if (daemon->doing_ra && FD_ISSET(daemon->icmp6fd, &rset))
+ if (daemon->doing_ra && poll_check(daemon->icmp6fd, POLLIN))
icmp6_packet(now);
#endif
# ifdef HAVE_SCRIPT
- if (daemon->helperfd != -1 && FD_ISSET(daemon->helperfd, &wset))
+ if (daemon->helperfd != -1 && poll_check(daemon->helperfd, POLLIN))
helper_write();
# endif
#endif
@@ -1451,7 +1430,7 @@
#endif
}
-static int set_dns_listeners(time_t now, fd_set *set, int *maxfdp)
+static int set_dns_listeners(time_t now)
{
struct serverfd *serverfdp;
struct listener *listener;
@@ -1463,7 +1442,7 @@
for (transfer = daemon->tftp_trans; transfer; transfer = transfer->next)
{
tftp++;
- bump_maxfd(set, transfer->sockfd, maxfdp);
+ poll_listen(transfer->sockfd, POLLIN);
}
#endif
@@ -1472,18 +1451,18 @@
get_new_frec(now, &wait, 0);
for (serverfdp = daemon->sfds; serverfdp; serverfdp = serverfdp->next)
- bump_maxfd(set, serverfdp->fd, maxfdp);
+ poll_listen(serverfdp->fd, POLLIN);
if (daemon->port != 0 && !daemon->osport)
for (i = 0; i < RANDOM_SOCKS; i++)
if (daemon->randomsocks[i].refcount != 0)
- bump_maxfd(set, daemon->randomsocks[i].fd, maxfdp);
+ poll_listen(daemon->randomsocks[i].fd, POLLIN);
for (listener = daemon->listeners; listener; listener = listener->next)
{
/* only listen for queries if we have resources */
if (listener->fd != -1 && wait == 0)
- bump_maxfd(set, listener->fd, maxfdp);
+ poll_listen(listener->fd, POLLIN);
/* death of a child goes through the select loop, so
we don't need to explicitly arrange to wake up here */
@@ -1491,13 +1470,13 @@
for (i = 0; i < MAX_PROCS; i++)
if (daemon->tcp_pids[i] == 0)
{
- bump_maxfd(set, listener->tcpfd, maxfdp);
+ poll_listen(listener->tcpfd, POLLIN);
break;
}
#ifdef HAVE_TFTP
if (tftp <= daemon->tftp_max && listener->tftpfd != -1)
- bump_maxfd(set, listener->tftpfd, maxfdp);
+ poll_listen(listener->tftpfd, POLLIN);
#endif
}
@@ -1505,33 +1484,33 @@
return wait;
}
-static void check_dns_listeners(fd_set *set, time_t now)
+static void check_dns_listeners(time_t now)
{
struct serverfd *serverfdp;
struct listener *listener;
int i;
for (serverfdp = daemon->sfds; serverfdp; serverfdp = serverfdp->next)
- if (FD_ISSET(serverfdp->fd, set))
+ if (poll_check(serverfdp->fd, POLLIN))
reply_query(serverfdp->fd, serverfdp->source_addr.sa.sa_family, now);
if (daemon->port != 0 && !daemon->osport)
for (i = 0; i < RANDOM_SOCKS; i++)
if (daemon->randomsocks[i].refcount != 0 &&
- FD_ISSET(daemon->randomsocks[i].fd, set))
+ poll_check(daemon->randomsocks[i].fd, POLLIN))
reply_query(daemon->randomsocks[i].fd, daemon->randomsocks[i].family, now);
for (listener = daemon->listeners; listener; listener = listener->next)
{
- if (listener->fd != -1 && FD_ISSET(listener->fd, set))
+ if (listener->fd != -1 && poll_check(listener->fd, POLLIN))
receive_query(listener, now);
#ifdef HAVE_TFTP
- if (listener->tftpfd != -1 && FD_ISSET(listener->tftpfd, set))
+ if (listener->tftpfd != -1 && poll_check(listener->tftpfd, POLLIN))
tftp_request(listener, now);
#endif
- if (listener->tcpfd != -1 && FD_ISSET(listener->tcpfd, set))
+ if (listener->tcpfd != -1 && poll_check(listener->tcpfd, POLLIN))
{
int confd, client_ok = 1;
struct irec *iface = NULL;
@@ -1772,51 +1751,41 @@
for (now = start = dnsmasq_time(), timeout_count = 0;
(difftime(now, start) < (float)PING_WAIT) && (timeout_count < PING_WAIT * 4);)
{
- struct timeval tv;
- fd_set rset, wset;
struct sockaddr_in faddr;
- int maxfd = fd;
socklen_t len = sizeof(faddr);
- tv.tv_usec = 250000;
- tv.tv_sec = 0;
-
- FD_ZERO(&rset);
- FD_ZERO(&wset);
- FD_SET(fd, &rset);
- set_dns_listeners(now, &rset, &maxfd);
- set_log_writer(&wset, &maxfd);
+ poll_reset();
+ poll_listen(fd, POLLIN);
+ set_dns_listeners(now);
+ set_log_writer();
#ifdef HAVE_DHCP6
if (daemon->doing_ra)
- bump_maxfd(&rset, daemon->icmp6fd, &maxfd);
+ poll_listen(daemon->icmp6fd, POLLIN);
#endif
- rc = select(maxfd+1, &rset, &wset, NULL, &tv);
+ rc = do_poll(250);
if (rc < 0)
- {
- FD_ZERO(&rset);
- FD_ZERO(&wset);
- }
+ continue;
else if (rc == 0)
timeout_count++;
now = dnsmasq_time();
- check_log_writer(&wset);
- check_dns_listeners(&rset, now);
+ check_log_writer(0);
+ check_dns_listeners(now);
#ifdef HAVE_DHCP6
- if (daemon->doing_ra && FD_ISSET(daemon->icmp6fd, &rset))
+ if (daemon->doing_ra && poll_check(daemon->icmp6fd, POLLIN))
icmp6_packet(now);
#endif
#ifdef HAVE_TFTP
- check_tftp_listeners(&rset, now);
+ check_tftp_listeners(now);
#endif
- if (FD_ISSET(fd, &rset) &&
+ if (poll_check(fd, POLLIN) &&
recvfrom(fd, &packet, sizeof(packet), 0,
(struct sockaddr *)&faddr, &len) == sizeof(packet) &&
saddr.sin_addr.s_addr == faddr.sin_addr.s_addr &&