time: use `Duration(C.INT64_MAX)` as infinite (#10539)

vlib/net/common.v

@@ -14,7 +14,7 @@ pub const no_timeout = time.Duration(0)
 
 // infinite_timeout should be given to functions when an infinite_timeout is wanted (i.e. functions
 // only ever return with data)
-pub const infinite_timeout = time.Duration(-1)
+pub const infinite_timeout = time.infinite
 
 // Shutdown shutsdown a socket and closes it
 fn shutdown(handle int) ? {
@@ -34,7 +34,7 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 	C.FD_ZERO(&set)
 	C.FD_SET(handle, &set)
 
-	seconds := timeout.milliseconds() / 1000
+	seconds := timeout / time.second
 	microseconds := time.Duration(timeout - (seconds * time.second)).microseconds()
 
 	mut tt := C.timeval{
@@ -93,9 +93,8 @@ fn select_with_retry(handle int, test Select, timeout time.Duration) ?bool {
 // wait_for_common wraps the common wait code
 fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test Select) ? {
 	if deadline.unix == 0 {
-		// only accept infinite_timeout as a valid
-		// negative timeout - it is handled in @select however
-		if timeout < 0 && timeout != net.infinite_timeout {
+		// do not accept negative timeout
+		if timeout < 0 {
 			return err_timed_out
 		}
 		ready := select_with_retry(handle, test, timeout) ?

vlib/net/unix/common.v

@@ -29,8 +29,8 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 	C.FD_ZERO(&set)
 	C.FD_SET(handle, &set)
 
-	seconds := timeout.milliseconds() / 1000
-	microseconds := timeout - (seconds * time.second)
+	seconds := timeout / time.second
+	microseconds := time.Duration(timeout - (seconds * time.second)).microseconds()
 
 	mut tt := C.timeval{
 		tv_sec: u64(seconds)
@@ -63,9 +63,8 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 // wait_for_common wraps the common wait code
 fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test Select) ? {
 	if deadline.unix == 0 {
-		// only accept infinite_timeout as a valid
-		// negative timeout - it is handled in @select however
-		if timeout < 0 && timeout != unix.infinite_timeout {
+		// do not accept negative timeout
+		if timeout < 0 {
 			return net.err_timed_out
 		}
 		ready := @select(handle, test, timeout) ?
@@ -117,7 +116,7 @@ const (
 // infinite_timeout should be given to functions when an infinite_timeout is wanted (i.e. functions
 // only ever return with data)
 const (
-	infinite_timeout = time.Duration(-1)
+	infinite_timeout = time.infinite
 )
 
 [inline]

vlib/os/notify/backend_linux.c.v

@@ -107,10 +107,7 @@ fn (mut en EpollNotifier) wait(timeout time.Duration) []FdEvent {
 	//       the added bonus of making EpollNotifier thread safe
 	events := [512]C.epoll_event{}
 	// populate events with the new events
-	to := match timeout {
-		time.infinite { -1 }
-		else { int(timeout / time.millisecond) }
-	}
+	to := timeout.sys_milliseconds()
 	count := C.epoll_wait(en.epoll_fd, &events[0], events.len, to)
 
 	if count > 0 {

vlib/sync/channel_select_test.v

@@ -8,6 +8,8 @@
 
 module sync
 
+import time
+
 fn do_rec_i64(mut ch Channel) {
 	mut sum := i64(0)
 	for _ in 0 .. 300 {
@@ -56,7 +58,7 @@ fn test_select() {
 	mut sl := i64(0)
 	mut objs := [voidptr(&ri), &sl, &rl, &rb]
 	for _ in 0 .. 1200 {
-		idx := channel_select(mut channels, directions, mut objs, -1)
+		idx := channel_select(mut channels, directions, mut objs, time.infinite)
 		match idx {
 			0 {
 				sum += ri

vlib/sync/channels.v

@@ -602,8 +602,8 @@ fn (mut ch Channel) try_pop_priv(dest voidptr, no_block bool) ChanState {
 }
 
 // Wait `timeout` on any of `channels[i]` until one of them can push (`is_push[i] = true`) or pop (`is_push[i] = false`)
-// object referenced by `objrefs[i]`. `timeout < 0` means wait unlimited time. `timeout == 0` means return immediately
-// if no transaction can be performed without waiting.
+// object referenced by `objrefs[i]`. `timeout = time.infinite` means wait unlimited time. `timeout <= 0` means return
+// immediately if no transaction can be performed without waiting.
 // return value: the index of the channel on which a transaction has taken place
 //               -1 if waiting for a transaction has exceeded timeout
 //               -2 if all channels are closed
@@ -646,7 +646,11 @@ pub fn channel_select(mut channels []&Channel, dir []Direction, mut objrefs []vo
 			C.atomic_store_u16(&ch.read_sub_mtx, u16(0))
 		}
 	}
-	stopwatch := if timeout <= 0 { time.StopWatch{} } else { time.new_stopwatch({}) }
+	stopwatch := if timeout == time.infinite || timeout <= 0 {
+		time.StopWatch{}
+	} else {
+		time.new_stopwatch({})
+	}
 	mut event_idx := -1 // negative index means `timed out`
 
 	outer: for {
@@ -679,10 +683,10 @@ pub fn channel_select(mut channels []&Channel, dir []Direction, mut objrefs []vo
 			event_idx = -2
 			break outer
 		}
-		if timeout == 0 {
+		if timeout <= 0 {
 			break outer
 		}
-		if timeout > 0 {
+		if timeout != time.infinite {
 			remaining := timeout - stopwatch.elapsed()
 			if !sem.timed_wait(remaining) {
 				break outer

vlib/sync/sync_windows.c.v

@@ -176,7 +176,7 @@ pub fn (mut sem Semaphore) timed_wait(timeout time.Duration) bool {
 	C.GetSystemTimeAsFileTime(&ft_start)
 	time_end := ((u64(ft_start.dwHighDateTime) << 32) | ft_start.dwLowDateTime) +
 		u64(timeout / (100 * time.nanosecond))
-	mut t_ms := u32(timeout / time.millisecond)
+	mut t_ms := timeout.sys_milliseconds()
 	C.AcquireSRWLockExclusive(&sem.mtx)
 	mut res := 0
 	c = C.atomic_load_u32(&sem.count)

vlib/time/time.v

@@ -394,7 +394,7 @@ pub const (
 	second      = Duration(1000 * millisecond)
 	minute      = Duration(60 * second)
 	hour        = Duration(60 * minute)
-	infinite    = Duration(-1)
+	infinite    = Duration(C.INT64_MAX)
 )
 
 // nanoseconds returns the duration as an integer number of nanoseconds.

vlib/time/time_nix.c.v

@@ -149,3 +149,15 @@ pub fn sleep(duration Duration) {
 		}
 	}
 }
+
+// some *nix system functions (e.g. `C.poll()`, C.epoll_wait()) accept an `int`
+// value as *timeout in milliseconds* with the special value `-1` meaning "infinite"
+pub fn (d Duration) sys_milliseconds() int {
+	if d > C.INT32_MAX * millisecond { // treat 2147483647000001 .. C.INT64_MAX as "infinite"
+		return -1
+	} else if d <= 0 {
+		return 0 // treat negative timeouts as 0 - consistent with Unix behaviour
+	} else {
+		return int(d / millisecond)
+	}
+}

vlib/time/time_windows.c.v

@@ -225,3 +225,15 @@ pub fn wait(duration Duration) {
 pub fn sleep(duration Duration) {
 	C.Sleep(int(duration / millisecond))
 }
+
+// some Windows system functions (e.g. `C.WaitForSingleObject()`) accept an `u32`
+// value as *timeout in milliseconds* with the special value `u32(-1)` meaning "infinite"
+pub fn (d Duration) sys_milliseconds() u32 {
+	if d >= u32(-1) * millisecond { // treat 4294967295000000 .. C.INT64_MAX as "infinite"
+		return u32(-1)
+	} else if d <= 0 {
+		return 0 // treat negative timeouts as 0 - consistent with Unix behaviour
+	} else {
+		return u32(d / millisecond)
+	}
+}

vlib/v/gen/c/cgen.v

@@ -4102,7 +4102,7 @@ fn (mut g Gen) select_expr(node ast.SelectExpr) {
 	} else if has_else {
 		g.write('0')
 	} else {
-		g.write('-1')
+		g.write('_const_time__infinite')
 	}
 	g.writeln(');')
 	// free the temps that were created