Windows port: putting some bases in place for new tool system.

Here, clean window class handler, which prevents regging a class
twice and unregging a class which isn't regged.

The stuff I'm adding is not set in a stone. It may be modified or
even removed at any moment.

desmume/src/windows/CWindow.cpp

@@ -22,6 +22,67 @@
 #include "CWindow.h"
 #include "debug.h"
 
+//-----------------------------------------------------------------------------
+// Window class handling
+//-----------------------------------------------------------------------------
+
+vector<string> ReggedWndClasses;
+
+bool RegWndClass(string name, WNDPROC wndProc, int extraSize)
+{
+	return RegWndClass(name, wndProc, 0, NULL, extraSize);
+}
+
+bool RegWndClass(string name, WNDPROC wndProc, HICON icon, int extraSize)
+{
+	return RegWndClass(name, wndProc, 0, icon, extraSize);
+}
+
+bool RegWndClass(string name, WNDPROC wndProc, UINT style, HICON icon, int extraSize)
+{
+	// If the class is already regged, don't re-reg it
+	if (find(ReggedWndClasses.begin(), ReggedWndClasses.end(), name) != ReggedWndClasses.end())
+		return true;
+
+	WNDCLASSEX wc;
+
+	wc.cbSize         = sizeof(wc);
+	wc.lpszClassName  = name.c_str();
+	wc.hInstance      = hAppInst;
+	wc.lpfnWndProc    = wndProc;
+	wc.hCursor        = LoadCursor(NULL, IDC_ARROW);
+	wc.hIcon          = icon;
+	wc.lpszMenuName   = 0;
+	wc.hbrBackground  = GetSysColorBrush(COLOR_BTNFACE);
+	wc.style          = style;
+	wc.cbClsExtra     = 0;
+	wc.cbWndExtra     = extraSize;
+	wc.hIconSm        = 0;
+
+	if (RegisterClassEx(&wc) != 0)
+	{
+		// If registration succeeded, add the class name into the list
+		ReggedWndClasses.push_back(name);
+		return true;
+	}
+	else
+		return false;
+}
+
+void UnregWndClass(string name)
+{
+	vector<string>::iterator it = find(ReggedWndClasses.begin(), ReggedWndClasses.end(), name);
+
+	// If the class wasn't regged, we can't unreg it :P
+	if (it == ReggedWndClasses.end())
+		return;
+
+	// Otherwise unreg the class and remove its name from the list
+	UnregisterClass(name.c_str(), hAppInst);
+	ReggedWndClasses.erase(it);
+}
+
+
 WINCLASS::WINCLASS(LPSTR rclass, HINSTANCE hInst)
 {
 	memset(regclass, 0, sizeof(regclass));

desmume/src/windows/CWindow.h

@@ -24,6 +24,23 @@
 
 #include "../common.h"
 
+#include <string>
+#include <vector>
+#include <algorithm>
+
+using namespace std;
+
+//-----------------------------------------------------------------------------
+// Window class handling
+//-----------------------------------------------------------------------------
+
+bool RegWndClass(string name, WNDPROC wndProc, int extraSize = 0);
+bool RegWndClass(string name, WNDPROC wndProc, HICON icon, int extraSize = 0);
+bool RegWndClass(string name, WNDPROC wndProc, UINT style, HICON icon, int extraSize = 0);
+
+void UnregWndClass(string name);
+
+
 class WINCLASS
 {
 private:

desmume/src/windows/main.cpp

@@ -1473,23 +1473,6 @@ void ChangeLanguage(int id)
 	MenuInit();
 }
 
-int RegClass(WNDPROC Proc, LPCTSTR szName)
-{
-	WNDCLASS	wc;
-
-	wc.style = CS_DBLCLKS;
-	wc.cbClsExtra = wc.cbWndExtra=0;
-	wc.lpfnWndProc=Proc;
-	wc.hInstance=hAppInst;
-	wc.hIcon=LoadIcon(hAppInst,"ICONDESMUME");
-	wc.hCursor=LoadCursor(NULL,IDC_ARROW);
-	wc.hbrBackground=(HBRUSH)(COLOR_BACKGROUND);
-	wc.lpszMenuName=(LPCTSTR)NULL;
-	wc.lpszClassName=szName;
-	wc.cbClsExtra = 0;
-	wc.cbWndExtra = 0;
-	return RegisterClass(&wc);
-}
 
 static void ExitRunLoop()
 {
@@ -1605,7 +1588,7 @@ int _main()
 	}*/
 	ColorCtrl_Register();
 
-	if (!RegClass(WindowProcedure, "DeSmuME"))
+	if (!RegWndClass("DeSmuME", WindowProcedure, CS_DBLCLKS, LoadIcon(hAppInst, "ICONDESMUME")))
 	{
 		MessageBox(NULL, "Error registering windows class", "DeSmuME", MB_OK);
 		exit(-1);
@@ -1981,6 +1964,8 @@ int _main()
 	if (lpBackSurface != NULL) IDirectDraw7_Release(lpBackSurface);
 	if (lpDDraw != NULL) IDirectDraw7_Release(lpDDraw);
 
+	UnregWndClass("DeSmuME");
+
 	return 0;
 }