replace windows version checks with compat bits

this saves us from calling GetVersion() and massaging the result
in hot code paths

1 files changed, 46 insertions, 19 deletions

diff --git a/alf/alfcompat.h b/alf/alfcompat.h
index 8186492..eeb70da 100644
--- a/alf/alfcompat.h
+++ b/alf/alfcompat.h
@@ -15,25 +15,6 @@ extern IMAGE_DOS_HEADER __ImageBase;
 #endif
 #define ALF_HINSTANCE ((HINSTANCE)&__ImageBase)
 
-static inline BOOL ALF_Compat_IsMinWindowsVersion(DWORD major, DWORD minor)
-{
-    DWORD v = GetVersion();
-    DWORD vMajor = LOBYTE(LOWORD(v));
-    DWORD vMinor = HIBYTE(LOWORD(v));
-
-    return vMajor > major || (vMajor == major && vMinor >= minor);
-}
-
-static inline BOOL ALF_Compat_IsWin9x(void)
-{
-    return GetVersion() >= 0x80000000;
-}
-
-static inline BOOL ALF_Compat_IsWinNT(void)
-{
-    return GetVersion() < 0x80000000;
-}
-
 typedef struct {
     UINT     cbSize;
     int      iBorderWidth;
@@ -144,3 +125,49 @@ extern HRESULT (WINAPI *ALF_Compat_EndBufferedAnimation)(ALF_Compat_HANIMATIONBU
 extern BOOL (WINAPI *ALF_Compat_BufferedPaintRenderAnimation)(HWND,HDC);
 extern HRESULT (WINAPI *ALF_Compat_GetThemeTransitionDuration)(HTHEME,int,int,int,int,DWORD*);
 extern HRESULT (WINAPI *ALF_Compat_GetThemeColor)(HTHEME,int,int,int,COLORREF*);
+
+// compatibility bits
+
+#define ALF_COMPAT_ISNT         1
+#define ALF_COMPAT_IS40         2
+#define ALF_COMPAT_ISW2K        4
+#define ALF_COMPAT_ISXP         8
+#define ALF_COMPAT_ISVISTA     16
+#define ALF_COMPAT_ISCOMCTLV6  32
+
+extern DWORD _alf_compatBits;
+
+static inline BOOL ALF_Compat_IsWin9x(void)
+{
+    return !(_alf_compatBits & ALF_COMPAT_ISNT);
+}
+
+static inline BOOL ALF_Compat_IsNT(void)
+{
+    return !!(_alf_compatBits & ALF_COMPAT_ISNT);
+}
+
+static inline BOOL ALF_Compat_Is40(void) // both NT 4.0 and Win95
+{
+    return !!(_alf_compatBits & ALF_COMPAT_IS40);
+}
+
+static inline BOOL ALF_Compat_Is2k(void)
+{
+    return !!(_alf_compatBits & ALF_COMPAT_ISW2K);
+}
+
+static inline BOOL ALF_Compat_IsXP(void)
+{
+    return !!(_alf_compatBits & ALF_COMPAT_ISXP);
+}
+
+static inline BOOL ALF_Compat_IsVista(void)
+{
+    return !!(_alf_compatBits & ALF_COMPAT_ISVISTA);
+}
+
+static inline BOOL ALF_Compat_IsComCtlV6(void)
+{
+    return !!(_alf_compatBits & ALF_COMPAT_ISCOMCTLV6);
+}