windows: correct signature of recently added GetWindowThreadProcessId
This function returns 0 and sets last error on failure. While this isn't
said explicitly on MSDN, there's no PID 0, and trivial reverse
engineering shows that this is the case. For example:
.text:00000001800035ED loc_1800035ED: ; CODE XREF: GetWindowThreadProcessId+23↑j
.text:00000001800035ED ; GetWindowThreadProcessId+3D↑j ...
.text:00000001800035ED mov ecx, 578h ; LastError
.text:00000001800035F2 call cs:__imp_RtlSetLastWin32Error
.text:00000001800035F9 nop dword ptr [rax+rax+00h]
.text:00000001800035FE
.text:00000001800035FE loc_1800035FE: ; CODE XREF: GetWindowThreadProcessId+65↑j
.text:00000001800035FE xor eax, eax
.text:0000000180003600 jmp short loc_1800035AA
This function was also just added by a user who is likely its only
consumer, so this error is not too late to fix.
Change-Id: I5dd24e78c006686bb8f1288ad0fe63cd67df56a6
Reviewed-on: https://go-review.googlesource.com/c/sys/+/285272
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Trust: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
diff --git a/windows/zsyscall_windows.go b/windows/zsyscall_windows.go
index cd5e852..8a79ea1 100644
--- a/windows/zsyscall_windows.go
+++ b/windows/zsyscall_windows.go
@@ -2904,9 +2904,12 @@
return
}
-func GetWindowThreadProcessId(hwnd HWND, pid *uint32) (tid uint32) {
- r0, _, _ := syscall.Syscall(procGetWindowThreadProcessId.Addr(), 2, uintptr(hwnd), uintptr(unsafe.Pointer(pid)), 0)
+func GetWindowThreadProcessId(hwnd HWND, pid *uint32) (tid uint32, err error) {
+ r0, _, e1 := syscall.Syscall(procGetWindowThreadProcessId.Addr(), 2, uintptr(hwnd), uintptr(unsafe.Pointer(pid)), 0)
tid = uint32(r0)
+ if tid == 0 {
+ err = errnoErr(e1)
+ }
return
}
