udhcp: use poll() instead of select()
function old new delta
udhcp_sp_read 65 46 -19
udhcp_sp_fd_set 79 54 -25
udhcpd_main 1530 1482 -48
udhcpc_main 2780 2730 -50
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-142) Total: -142 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/udhcp/common.h b/networking/udhcp/common.h
index a526494..ee12cf9 100644
--- a/networking/udhcp/common.h
+++ b/networking/udhcp/common.h
@@ -300,8 +300,8 @@
uint32_t dest_nip, int dest_port) FAST_FUNC;
void udhcp_sp_setup(void) FAST_FUNC;
-int udhcp_sp_fd_set(fd_set *rfds, int extra_fd) FAST_FUNC;
-int udhcp_sp_read(const fd_set *rfds) FAST_FUNC;
+void udhcp_sp_fd_set(struct pollfd *pfds, int extra_fd) FAST_FUNC;
+int udhcp_sp_read(struct pollfd *pfds) FAST_FUNC;
int udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *mac) FAST_FUNC;
diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c
index 64339c9..067d351 100644
--- a/networking/udhcp/d6_dhcpc.c
+++ b/networking/udhcp/d6_dhcpc.c
@@ -935,9 +935,7 @@
int timeout; /* must be signed */
unsigned already_waited_sec;
unsigned opt;
- int max_fd;
int retval;
- fd_set rfds;
setup_common_bufsiz();
@@ -1063,7 +1061,8 @@
* "continue" statements in code below jump to the top of the loop.
*/
for (;;) {
- struct timeval tv;
+ int tv;
+ struct pollfd pfds[2];
struct d6_packet packet;
uint8_t *packet_end;
/* silence "uninitialized!" warning */
@@ -1078,16 +1077,15 @@
* to change_listen_mode(). Thus we open listen socket
* BEFORE we send renew request (see "case BOUND:"). */
- max_fd = udhcp_sp_fd_set(&rfds, sockfd);
+ udhcp_sp_fd_set(pfds, sockfd);
- tv.tv_sec = timeout - already_waited_sec;
- tv.tv_usec = 0;
+ tv = timeout - already_waited_sec;
retval = 0;
/* If we already timed out, fall through with retval = 0, else... */
- if ((int)tv.tv_sec > 0) {
- log1("waiting on select %u seconds", (int)tv.tv_sec);
+ if (tv > 0) {
+ log1("waiting on select %u seconds", tv);
timestamp_before_wait = (unsigned)monotonic_sec();
- retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
+ retval = poll(pfds, 2, tv * 1000);
if (retval < 0) {
/* EINTR? A signal was caught, don't panic */
if (errno == EINTR) {
@@ -1222,8 +1220,8 @@
/* select() didn't timeout, something happened */
/* Is it a signal? */
- /* note: udhcp_sp_read checks FD_ISSET before reading */
- switch (udhcp_sp_read(&rfds)) {
+ /* note: udhcp_sp_read checks poll result before reading */
+ switch (udhcp_sp_read(pfds)) {
case SIGUSR1:
client_config.first_secs = 0; /* make secs field count from 0 */
already_waited_sec = 0;
@@ -1258,7 +1256,7 @@
}
/* Is it a packet? */
- if (listen_mode == LISTEN_NONE || !FD_ISSET(sockfd, &rfds))
+ if (listen_mode == LISTEN_NONE || !pfds[1].revents)
continue; /* no */
{
@@ -1460,8 +1458,8 @@
if (lease_seconds < 0x10)
lease_seconds = 0x10;
/// TODO: check for 0 lease time?
- if (lease_seconds >= 0x10000000)
- lease_seconds = 0x0fffffff;
+ if (lease_seconds > 0x7fffffff / 1000)
+ lease_seconds = 0x7fffffff / 1000;
/* enter bound state */
timeout = lease_seconds / 2;
bb_error_msg("lease obtained, lease time %u",
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 0e23626..8f7f59e 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -1281,9 +1281,7 @@
unsigned already_waited_sec;
unsigned opt;
IF_FEATURE_UDHCPC_ARPING(unsigned arpping_ms;)
- int max_fd;
int retval;
- fd_set rfds;
setup_common_bufsiz();
@@ -1432,7 +1430,8 @@
* "continue" statements in code below jump to the top of the loop.
*/
for (;;) {
- struct timeval tv;
+ int tv;
+ struct pollfd pfds[2];
struct dhcp_packet packet;
/* silence "uninitialized!" warning */
unsigned timestamp_before_wait = timestamp_before_wait;
@@ -1446,16 +1445,15 @@
* to change_listen_mode(). Thus we open listen socket
* BEFORE we send renew request (see "case BOUND:"). */
- max_fd = udhcp_sp_fd_set(&rfds, sockfd);
+ udhcp_sp_fd_set(pfds, sockfd);
- tv.tv_sec = timeout - already_waited_sec;
- tv.tv_usec = 0;
+ tv = timeout - already_waited_sec;
retval = 0;
/* If we already timed out, fall through with retval = 0, else... */
- if ((int)tv.tv_sec > 0) {
- log1("waiting on select %u seconds", (int)tv.tv_sec);
+ if (tv > 0) {
+ log1("waiting on select %u seconds", tv);
timestamp_before_wait = (unsigned)monotonic_sec();
- retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
+ retval = poll(pfds, 2, tv * 1000);
if (retval < 0) {
/* EINTR? A signal was caught, don't panic */
if (errno == EINTR) {
@@ -1591,8 +1589,8 @@
/* select() didn't timeout, something happened */
/* Is it a signal? */
- /* note: udhcp_sp_read checks FD_ISSET before reading */
- switch (udhcp_sp_read(&rfds)) {
+ /* note: udhcp_sp_read checks poll result before reading */
+ switch (udhcp_sp_read(pfds)) {
case SIGUSR1:
client_config.first_secs = 0; /* make secs field count from 0 */
already_waited_sec = 0;
@@ -1627,7 +1625,7 @@
}
/* Is it a packet? */
- if (listen_mode == LISTEN_NONE || !FD_ISSET(sockfd, &rfds))
+ if (listen_mode == LISTEN_NONE || !pfds[1].revents)
continue; /* no */
{
@@ -1742,8 +1740,8 @@
/* paranoia: must not be too small and not prone to overflows */
if (lease_seconds < 0x10)
lease_seconds = 0x10;
- if (lease_seconds >= 0x10000000)
- lease_seconds = 0x0fffffff;
+ if (lease_seconds > 0x7fffffff / 1000)
+ lease_seconds = 0x7fffffff / 1000;
}
#if ENABLE_FEATURE_UDHCPC_ARPING
if (opt & OPT_a) {
diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index e116ba3..5eff026 100644
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -794,7 +794,7 @@
int udhcpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int udhcpd_main(int argc UNUSED_PARAM, char **argv)
{
- int server_socket = -1, retval, max_sock;
+ int server_socket = -1, retval;
uint8_t *state;
unsigned timeout_end;
unsigned num_ips;
@@ -891,10 +891,10 @@
continue_with_autotime:
timeout_end = monotonic_sec() + server_config.auto_time;
while (1) { /* loop until universe collapses */
- fd_set rfds;
+ struct pollfd pfds[2];
struct dhcp_packet packet;
int bytes;
- struct timeval tv;
+ int tv;
uint8_t *server_id_opt;
uint8_t *requested_ip_opt;
uint32_t requested_nip = requested_nip; /* for compiler */
@@ -906,16 +906,11 @@
server_config.interface);
}
- max_sock = udhcp_sp_fd_set(&rfds, server_socket);
- if (server_config.auto_time) {
- /* cast to signed is essential if tv_sec is wider than int */
- tv.tv_sec = (int)(timeout_end - monotonic_sec());
- tv.tv_usec = 0;
- }
+ udhcp_sp_fd_set(pfds, server_socket);
+ tv = timeout_end - monotonic_sec();
retval = 0;
- if (!server_config.auto_time || tv.tv_sec > 0) {
- retval = select(max_sock + 1, &rfds, NULL, NULL,
- server_config.auto_time ? &tv : NULL);
+ if (!server_config.auto_time || tv > 0) {
+ retval = poll(pfds, 2, server_config.auto_time ? tv * 1000 : -1);
}
if (retval == 0) {
write_leases();
@@ -926,7 +921,7 @@
continue;
}
- switch (udhcp_sp_read(&rfds)) {
+ switch (udhcp_sp_read(pfds)) {
case SIGUSR1:
bb_error_msg("received %s", "SIGUSR1");
write_leases();
diff --git a/networking/udhcp/signalpipe.c b/networking/udhcp/signalpipe.c
index 30bccd6..b101b4c 100644
--- a/networking/udhcp/signalpipe.c
+++ b/networking/udhcp/signalpipe.c
@@ -48,28 +48,29 @@
, signal_handler);
}
-/* Quick little function to setup the rfds. Will return the
- * max_fd for use with select. Limited in that you can only pass
- * one extra fd */
-int FAST_FUNC udhcp_sp_fd_set(fd_set *rfds, int extra_fd)
+/* Quick little function to setup the pfds.
+ * Limited in that you can only pass one extra fd.
+ */
+void FAST_FUNC udhcp_sp_fd_set(struct pollfd pfds[2], int extra_fd)
{
- FD_ZERO(rfds);
- FD_SET(signal_pipe.rd, rfds);
+ pfds[0].fd = signal_pipe.rd;
+ pfds[0].events = POLLIN;
+ pfds[1].fd = -1;
if (extra_fd >= 0) {
close_on_exec_on(extra_fd);
- FD_SET(extra_fd, rfds);
+ pfds[1].fd = extra_fd;
+ pfds[1].events = POLLIN;
}
- return signal_pipe.rd > extra_fd ? signal_pipe.rd : extra_fd;
}
/* Read a signal from the signal pipe. Returns 0 if there is
* no signal, -1 on error (and sets errno appropriately), and
* your signal on success */
-int FAST_FUNC udhcp_sp_read(const fd_set *rfds)
+int FAST_FUNC udhcp_sp_read(struct pollfd pfds[2])
{
unsigned char sig;
- if (!FD_ISSET(signal_pipe.rd, rfds))
+ if (!pfds[0].revents)
return 0;
if (safe_read(signal_pipe.rd, &sig, 1) != 1)