Rework the calculation of the select timeout in io() to be based on absolute wake time

An absolute wake time is now calculated and updated by set_server_bits(),
TimerTimeout() and tclTimerTimeout().  This is then used to calculate the actual
select() timeout, instead of having those functions calculate a relative timeout
value themselves.  This significantly simplifies those functions, since the
underlying values tend to be recorded as absolute times.

It also allows us to disentangle tclTimeTimeout from TimerTimeout(), and move the
responsibility for calculating the QUEUE_SENDS wake time from TimerTimeout() to
set_server_bits() where it belongs.

The QUEUE_SENDS and CONNECT_DELAY wake up times will also now be correctly
calculated, based on the last sent time and connect time respectively.

include/server.h

@@ -227,7 +227,7 @@ extern	SGroup	*server_group_list;
 	void	BX_server_is_connected (int, int);
 	int	BX_parse_server_index (char *);
 	void	BX_parse_server_info (char *, char **, char **, char **, char **);
-	long	set_server_bits (fd_set *, fd_set *);
+	void set_server_bits (fd_set *rd, fd_set *wr, struct timeval *wake_time);
 	void	BX_set_server_itsname (int, char *);
 	void	BX_set_server_version (int, int);
 	char	*BX_get_possible_umodes(int);

include/tcl_bx.h

@@ -19,6 +19,7 @@ typedef struct {
 
 extern cmd_t C_msg[];
 extern cmd_t C_dcc[];
+void tclTimerTimeout(struct timeval *wake_time);
 int check_tcl_dcc (char *, char *, char *, int);
 
 void tcl_command (char *, char *, char *, char *);

include/timer.h

@@ -16,14 +16,9 @@ extern	int	kill_timer(char *);
 extern	void	BX_delete_all_timers (void);
 extern	int	timer_exists (char *ref);
 
-
+void TimerTimeout(struct timeval *wake_time);
-extern	time_t	TimerTimeout (void);
 char		*tcl_add_timer (TimerList **, long, char *, unsigned long);
 int 		tcl_remove_timer (TimerList **, unsigned long);
 int		timer_callback_exists(void *);
 
-time_t		tclTimerTimeout(time_t);
-
-#define MAGIC_TIMEOUT 100000000
-
 #endif /* _TIMER_H_ */

source/irc.c

@@ -1196,13 +1196,10 @@ extern void set_screens (fd_set *, fd_set *);
 void BX_io (const char *what)
 {
 	static int level = 0;
-	long clock_timeout = 0, 
+	long clock_timeout = 0;
-		timer_timeout = 0,
+	struct timeval my_now,
-		server_timeout = 0,
-		real_timeout = 0; 
-	static struct timeval my_now,
 		my_timer,
-		*time_ptr = &my_timer;
+		timeout;
 	int hold_over, rc;
 	fd_set rd, wd;
 	static int old_level = 0;
@@ -1211,9 +1208,6 @@ void BX_io (const char *what)
 
 	level++;
 
-	get_time(&my_now);
-	now = my_now.tv_sec;
-	
 	if (x_debug & DEBUG_WAITS)
 	{
 		if (level != old_level)
@@ -1237,6 +1231,9 @@ void BX_io (const char *what)
 
 	caller[level] = what;
 
+	get_time(&my_now);
+	now = my_now.tv_sec;
+
 	/* CHECK FOR CPU SAVER MODE */
 	if (!cpu_saver && get_int_var(CPU_SAVER_AFTER_VAR))
 		if (now - idle_time > get_int_var(CPU_SAVER_AFTER_VAR) * 60)
@@ -1250,7 +1247,6 @@ void BX_io (const char *what)
 #ifndef GUI
 	set_screens(&rd, &wd);
 #endif
-	server_timeout = set_server_bits(&rd, &wd);
 	set_process_bits(&rd);
 	set_socket_read(&rd, &wd);
 	set_nslookupfd(&rd);
@@ -1258,37 +1254,39 @@ void BX_io (const char *what)
 	gui_setfd(&rd);
 #endif
 
-	clock_timeout = (60 - (my_now.tv_sec % 60)) * 1000;
+	clock_timeout = 60 - (my_now.tv_sec % 60);
 	if (cpu_saver && get_int_var(CPU_SAVER_EVERY_VAR))
-		clock_timeout += (get_int_var(CPU_SAVER_EVERY_VAR) - 1) * 60000;
+		clock_timeout += (get_int_var(CPU_SAVER_EVERY_VAR) - 1) * 60;
 
-	timer_timeout = TimerTimeout();
+	my_timer.tv_sec = my_now.tv_sec + clock_timeout;
+	my_timer.tv_usec = 0;
 
-	if ((hold_over = unhold_windows()))
+	set_server_bits(&rd, &wd, &my_timer);
-		real_timeout = 0;
-	else if (timer_timeout <= clock_timeout)
-		real_timeout = timer_timeout;
-	else
-		real_timeout = clock_timeout;
 
-	if (server_timeout >= 0 && server_timeout < real_timeout)
+	tclTimerTimeout(&my_timer);
-		real_timeout = server_timeout;
 
-	time_ptr = &my_timer;
+	TimerTimeout(&my_timer);
 
-	if (real_timeout == -1)
+	if ((hold_over = unhold_windows()) || time_cmp(&my_timer, &my_now) < 0)
-		time_ptr = NULL;
+	{
+		timeout.tv_sec = 0;
+		timeout.tv_usec = 0;
+	}
 	else
 	{
-		time_ptr->tv_sec = real_timeout / 1000;
+		timeout.tv_sec = my_timer.tv_sec - my_now.tv_sec;
-		time_ptr->tv_usec = ((real_timeout % 1000) * 1000);
+		timeout.tv_usec = my_timer.tv_usec - my_now.tv_usec;
+		if (timeout.tv_usec < 0)
+		{
+			timeout.tv_sec--;
+			timeout.tv_usec += 1000000;
+		}
 	}
 	
 	/* GO AHEAD AND WAIT FOR SOME DATA TO COME IN */
-	switch ((rc = new_select(&rd, &wd, time_ptr)))
+	switch ((rc = new_select(&rd, &wd, &timeout)))
 	{
 		case 0:
-			if (server_timeout >= 0)
 			do_idle_server();
 			break;
 		case -1:
@@ -1309,7 +1307,8 @@ void BX_io (const char *what)
 		default:
 		{
 			cntl_c_hit = 0;
-			now = time(NULL);
+			get_time(&my_now);
+			now = my_now.tv_sec;
 			make_window_current(NULL);
 			do_server(&rd, &wd);
 			do_processes(&rd);
@@ -1327,7 +1326,8 @@ void BX_io (const char *what)
 		} 
 	}
 
-	now = time(NULL);
+	get_time(&my_now);
+	now = my_now.tv_sec;
 	ExecuteTimers();
 #ifdef WANT_TCL
 	check_utimers();

source/server.c

@@ -227,19 +227,19 @@ void close_unattached_servers(void)
  * set_server_bits: Sets the proper bits in the fd_set structure according to
  * which servers in the server list have currently active read descriptors.  
  */
-long	set_server_bits (fd_set *rd, fd_set *wr)
+void set_server_bits (fd_set *rd, fd_set *wr, struct timeval *wake_time)
 {
 	int	i;
-	long timeout = -1;
 
 	for (i = 0; i < number_of_servers; i++)
 	{
 		if (server_list[i].reconnect > 0)
 		{
-			/* CONNECT_DELAY is in seconds but we must
+			struct timeval connect_wake_time = server_list[i].connect_time;
-			 * return in milliseconds.
+			connect_wake_time.tv_sec += get_int_var(CONNECT_DELAY_VAR);
-			 */
+
-			timeout = get_int_var(CONNECT_DELAY_VAR)*1000;
+			if (time_cmp(wake_time, &connect_wake_time) > 0)
+				*wake_time = connect_wake_time;
 		}
 
 		if (server_list[i].read > -1)
@@ -250,9 +250,20 @@ long	set_server_bits (fd_set *rd, fd_set *wr)
 			FD_SET(server_list[i].write, wr);
 #endif
 	}
-	return timeout;
-}
 
+	/* Check for a QUEUE_SENDS wake_time */
+	if (serverqueue)
+	{
+		struct timeval queue_wake_time;
+
+		queue_wake_time.tv_sec = server_list[serverqueue->server].last_sent +
+			get_int_var(QUEUE_SENDS_VAR);
+		queue_wake_time.tv_usec = 0;
+
+		if (time_cmp(wake_time, &queue_wake_time) > 0)
+			*wake_time = queue_wake_time;
+	}
+}
 
 int timed_server (void *args, char *sub)
 {

source/tcl_public.c

@@ -1480,46 +1480,24 @@ long time_left;
 	}
 }
 
-static struct timeval current;
+void tclTimerTimeout(struct timeval *wake_time)
-
-time_t tclTimerTimeout(time_t timeout)
 {
-	register TimerList	*stack = NULL;
+	TimerList *stack = NULL;
-	long			this_timeout = 0;
 
-	if (timeout == 0)
-		return 0;
-	get_time(&current);
-	if ((stack = tcl_Pending_timers))
-	{
 	/* this is in minutes */
-		for (; stack; stack = stack->next)
+	for (stack = tcl_Pending_timers; stack; stack = stack->next)
-			if ((this_timeout = (BX_time_diff(current, stack->time)) * 1000) < timeout)
+		if (time_cmp(wake_time, &stack->time) > 0)
-				timeout = this_timeout;
+			*wake_time = stack->time;
-	}
-	if ((stack = tcl_Pending_utimers))
-	{
 	/* this is in seconds */
-		for (; stack; stack = stack->next)
+	for (stack = tcl_Pending_utimers; stack; stack = stack->next)
-			if ((this_timeout = (BX_time_diff(current, stack->time)) * 1000) < timeout)
+		if (time_cmp(wake_time, &stack->time) > 0)
-				timeout = this_timeout;
+			*wake_time = stack->time;
-	}
-#if defined(WINNT) || defined(__EMX__)
-	return (timeout == MAGIC_TIMEOUT) ? MAGIC_TIMEOUT : timeout;
-#else
-	return timeout;
-#endif
 }
 
 #else /* WANT_TCL */
 
-time_t tclTimerTimeout(time_t timeout)
+void tclTimerTimeout(struct timeval *wake_time)
 {
-#if defined(WINNT) || defined(__EMX__)
-	return (timeout == MAGIC_TIMEOUT) ? MAGIC_TIMEOUT : timeout;
-#else
-	return timeout < MAGIC_TIMEOUT ? timeout : MAGIC_TIMEOUT;
-#endif
 }
 
 int check_tcl_dcc(char *cmd, char *nick, char *host, int idx)

source/timer.c

@@ -600,25 +600,8 @@ static char *schedule_timer (TimerList *ntimer)
  * part of the call to select.
  */
 
-time_t TimerTimeout (void)
+void TimerTimeout(struct timeval *wake_time)
 {
-	time_t	timeout_in;
+	if (PendingTimers && time_cmp(wake_time, &PendingTimers->time) > 0)
-	time_t t = MAGIC_TIMEOUT;
+		*wake_time = PendingTimers->time;
-	
-	if (is_server_queue() && (t = get_int_var(QUEUE_SENDS_VAR)))
-		;
-	else
-		t = MAGIC_TIMEOUT;
-	if (!PendingTimers)
-		timeout_in = tclTimerTimeout(MAGIC_TIMEOUT);
-	else
-	{
-		timeout_in = (time_t)(time_until(&PendingTimers->time) * 1000);
-		timeout_in = (time_t)(tclTimerTimeout((timeout_in < 0) ? 0 : timeout_in));
-	}
-	
-	if (t < timeout_in)
-		timeout_in = t * 1000;
-		
-	return (timeout_in < 0) ? 0 : timeout_in;
 }