Set up initialization on Windows (2/2).

1 files changed, 77 insertions, 0 deletions

diff --git a/init_windows.go b/init_windows.go
new file mode 100644
index 0000000..bea6516
--- /dev/null
+++ b/init_windows.go
@@ -0,0 +1,77 @@
+// 8 february 2014
+package main
+
+import (
+	"fmt"
+//	"syscall"
+	"unsafe"
+)
+
+const (
+	windowclass = "gouiwndclass"
+)
+
+var (
+	hInstance		HANDLE
+	nCmdShow	int
+	// TODO font
+	// TODO common window class
+)
+
+// TODO is this trick documented in MSDN?
+func getWinMainhInstance() (err error) {
+	r1, _, err := kernel32.NewProc("GetModuleHandleW").Call(uintptr(NULL))
+	if r1 == 0 {		// failure
+		return err
+	}
+	hInstance = HANDLE(r1)
+	return nil
+}
+
+// TODO this is what MinGW-w64's crt (svn revision xxx) does; is it best? is any of this documented anywhere on MSDN?
+// TODO I highly doubt Windows API functions ever not fail, so figure out what to do should an error actually occur
+func getWinMainnCmdShow() (nCmdShow int, err error) {
+	var info struct {
+		cb				uint32
+		lpReserved		*uint16
+		lpDesktop			*uint16
+		lpTitle			*uint16
+		dwX				uint32
+		dwY				uint32
+		dwXSize			uint32
+		dwYSzie			uint32
+		dwXCountChars	uint32
+		dwYCountChars	uint32
+		dwFillAttribute		uint32
+		dwFlags			uint32
+		wShowWindow		uint16
+		cbReserved2		uint16
+		lpReserved2		*byte
+		hStdInput			HANDLE
+		hStdOutput		HANDLE
+		hStdError			HANDLE
+	}
+	const _STARTF_USESHOWWINDOW = 0x00000001
+
+	// does not fail according to MSDN
+	kernel32.NewProc("GetStartupInfoW").Call(uintptr(unsafe.Pointer(&info)))
+	if info.dwFlags & _STARTF_USESHOWWINDOW != 0 {
+		nCmdShow = int(info.wShowWindow)
+		return nil
+	}
+	nCmdShow = _SW_SHOWDEFAULT
+	return nil
+}
+
+func doWindowsInit() (err error) {
+	err = getWinMainhInstance()
+	if err != nil {
+		return fmt.Errorf("error getting WinMain hInstance: %v", err)
+	}
+	err = getWinMainnCmdShow()
+	if err != nil {
+		return fmt.Errorf("error getting WinMain nCmdShow: %v", err)
+	}
+	// TODO others
+	return nil		// all ready to go
+}