runtime: check for errors returned by windows sema calls

Add checks for failure of CreateEvent, SetEvent or
WaitForSingleObject. Any failures are considered fatal and
will throw() after printing an informative message.

Updates #16646

Change-Id: I3bacf9001d2abfa8667cc3aff163ff2de1c99915
Reviewed-on: https://go-review.googlesource.com/26655
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

1 files changed, 47 insertions, 4 deletions

diff --git a/src/runtime/os_windows.go b/src/runtime/os_windows.go
index 123ede9d14..0db57f8c5b 100644
--- a/src/runtime/os_windows.go
+++ b/src/runtime/os_windows.go
@@ -437,6 +437,13 @@ func writeConsoleUTF16(handle uintptr, b []uint16) {
 
 //go:nosplit
 func semasleep(ns int64) int32 {
+	const (
+		_WAIT_ABANDONED = 0x00000080
+		_WAIT_OBJECT_0  = 0x00000000
+		_WAIT_TIMEOUT   = 0x00000102
+		_WAIT_FAILED    = 0xFFFFFFFF
+	)
+
 	// store ms in ns to save stack space
 	if ns < 0 {
 		ns = _INFINITE
@@ -446,15 +453,44 @@ func semasleep(ns int64) int32 {
 			ns = 1
 		}
 	}
-	if stdcall2(_WaitForSingleObject, getg().m.waitsema, uintptr(ns)) != 0 {
-		return -1 // timeout
+
+	result := stdcall2(_WaitForSingleObject, getg().m.waitsema, uintptr(ns))
+	switch result {
+	case _WAIT_OBJECT_0: //signaled
+		return 0
+
+	case _WAIT_TIMEOUT:
+		return -1
+
+	case _WAIT_ABANDONED:
+		systemstack(func() {
+			throw("runtime.semasleep wait_abandoned")
+		})
+
+	case _WAIT_FAILED:
+		systemstack(func() {
+			print("runtime: waitforsingleobject wait_failed; errno=", getlasterror(), "\n")
+			throw("runtime.semasleep wait_failed")
+		})
+
+	default:
+		systemstack(func() {
+			print("runtime: waitforsingleobject unexpected; result=", result, "\n")
+			throw("runtime.semasleep unexpected")
+		})
 	}
-	return 0
+
+	return -1 // unreachable
 }
 
 //go:nosplit
 func semawakeup(mp *m) {
-	stdcall1(_SetEvent, mp.waitsema)
+	if stdcall1(_SetEvent, mp.waitsema) == 0 {
+		systemstack(func() {
+			print("runtime: setevent failed; errno=", getlasterror(), "\n")
+			throw("runtime.semawakeup")
+		})
+	}
 }
 
 //go:nosplit
@@ -463,6 +499,12 @@ func semacreate(mp *m) {
 		return
 	}
 	mp.waitsema = stdcall4(_CreateEventA, 0, 0, 0, 0)
+	if mp.waitsema == 0 {
+		systemstack(func() {
+			print("runtime: createevent failed; errno=", getlasterror(), "\n")
+			throw("runtime.semacreate")
+		})
+	}
 }
 
 // May run with m.p==nil, so write barriers are not allowed. This
@@ -475,6 +517,7 @@ func newosproc(mp *m, stk unsafe.Pointer) {
 	thandle := stdcall6(_CreateThread, 0, 0x20000,
 		funcPC(tstart_stdcall), uintptr(unsafe.Pointer(mp)),
 		_STACK_SIZE_PARAM_IS_A_RESERVATION, 0)
+
 	if thandle == 0 {
 		print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", getlasterror(), ")\n")
 		throw("runtime.newosproc")