Some doc corrections

[wxWidgets.git] / src / msw / utils.cpp

diff --git a/src/msw/utils.cpp b/src/msw/utils.cpp
index 2a9d0a99a4ed37c0c065ce1a9fa9aaa7eda030ea..e035e05457edc5fd0ba6712e59988239ab6cf2df 100644 (file)
--- a/src/msw/utils.cpp
+++ b/src/msw/utils.cpp
@@ -436,29 +436,14 @@ wxChar *wxGetUserHome(const wxString& user)
 bool wxDirExists(const wxString& dir)
 {
 #if defined(__WIN32__)
-    WIN32_FIND_DATA fileInfo;
+    DWORD attribs = GetFileAttributes(dir);
+    return ((attribs != (DWORD)-1) && (attribs & FILE_ATTRIBUTE_DIRECTORY));
 #else // Win16
     #ifdef __BORLANDC__
         struct ffblk fileInfo;
     #else
         struct find_t fileInfo;
     #endif
-#endif // Win32/16
-
-#if defined(__WIN32__)
-    HANDLE h = ::FindFirstFile(dir, &fileInfo);
-
-    if ( h == INVALID_HANDLE_VALUE )
-    {
-        wxLogLastError(wxT("FindFirstFile"));
-
-        return FALSE;
-    }
-
-    ::FindClose(h);
-
-    return (fileInfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
-#else // Win16
     // In Borland findfirst has a different argument
     // ordering from _dos_findfirst. But _dos_findfirst
     // _should_ be ok in both MS and Borland... why not?
@@ -1005,10 +990,22 @@ void wxGetMousePosition( int* x, int* y )
 // Return TRUE if we have a colour display
 bool wxColourDisplay()
 {
-    ScreenHDC dc;
-    int noCols = GetDeviceCaps(dc, NUMCOLORS);
+    // this function is called from wxDC ctor so it is called a *lot* of times
+    // hence we optimize it a bit but doign the check only once
+    //
+    // this should be MT safe as only the GUI thread (holding the GUI mutex)
+    // can call us
+    static int s_isColour = -1;
+
+    if ( s_isColour == -1 )
+    {
+        ScreenHDC dc;
+        int noCols = ::GetDeviceCaps(dc, NUMCOLORS);
+
+        s_isColour = (noCols == -1) || (noCols > 2);
+    }
 
-    return (noCols == -1) || (noCols > 2);
+    return s_isColour != 0;
 }
 
 // Returns depth of screen