diff --git a/system/events_windows.go b/system/events_windows.go new file mode 100644 index 0000000..23f7c61 --- /dev/null +++ b/system/events_windows.go @@ -0,0 +1,83 @@ +package system + +// This file implements syscalls for Win32 events which are not implemented +// in golang. + +import ( + "syscall" + "unsafe" +) + +const ( + EVENT_ALL_ACCESS = 0x1F0003 + EVENT_MODIFY_STATUS = 0x0002 +) + +var ( + procCreateEvent = modkernel32.NewProc("CreateEventW") + procOpenEvent = modkernel32.NewProc("OpenEventW") + procSetEvent = modkernel32.NewProc("SetEvent") + procResetEvent = modkernel32.NewProc("ResetEvent") + procPulseEvent = modkernel32.NewProc("PulseEvent") +) + +func CreateEvent(eventAttributes *syscall.SecurityAttributes, manualReset bool, initialState bool, name string) (handle syscall.Handle, err error) { + namep, _ := syscall.UTF16PtrFromString(name) + var _p1 uint32 = 0 + if manualReset { + _p1 = 1 + } + var _p2 uint32 = 0 + if initialState { + _p2 = 1 + } + r0, _, e1 := procCreateEvent.Call(uintptr(unsafe.Pointer(eventAttributes)), uintptr(_p1), uintptr(_p2), uintptr(unsafe.Pointer(namep))) + use(unsafe.Pointer(namep)) + handle = syscall.Handle(r0) + if handle == syscall.InvalidHandle { + err = e1 + } + return +} + +func OpenEvent(desiredAccess uint32, inheritHandle bool, name string) (handle syscall.Handle, err error) { + namep, _ := syscall.UTF16PtrFromString(name) + var _p1 uint32 = 0 + if inheritHandle { + _p1 = 1 + } + r0, _, e1 := procOpenEvent.Call(uintptr(desiredAccess), uintptr(_p1), uintptr(unsafe.Pointer(namep))) + use(unsafe.Pointer(namep)) + handle = syscall.Handle(r0) + if handle == syscall.InvalidHandle { + err = e1 + } + return +} + +func SetEvent(handle syscall.Handle) (err error) { + return setResetPulse(handle, procSetEvent) +} + +func ResetEvent(handle syscall.Handle) (err error) { + return setResetPulse(handle, procResetEvent) +} + +func PulseEvent(handle syscall.Handle) (err error) { + return setResetPulse(handle, procPulseEvent) +} + +func setResetPulse(handle syscall.Handle, proc *syscall.LazyProc) (err error) { + r0, _, _ := proc.Call(uintptr(handle)) + if r0 != 0 { + err = syscall.Errno(r0) + } + return +} + +var temp unsafe.Pointer + +// use ensures a variable is kept alive without the GC freeing while still needed +func use(p unsafe.Pointer) { + temp = p +}