use qBinaryFind instead of bsearch

depending on platform, qBinaryFind might be up to 3 times faster than bsearch
or a bit bit slower at the worst case; so why don't simply use qBinaryFind instead of bsearch and be an optimist? ;)

also we know that all color names are in the lower case already and thus
we can avoid lowercasing of them again and again, and again;
the name to find needs to be lowercased separately instead.

some color-by-name-lookup numbers:
before:
 0.000737 msecs per iteration (total: 3,684, iterations: 5000000)
after:
 0.000154 msecs per iteration (total: 771, iterations: 5000000)

Merge-request: 906
Reviewed-by: Olivier Goffart <olivier.goffart@nokia.com>

1 files changed, 8 insertions, 28 deletions

diff --git a/src/gui/painting/qcolor_p.cpp b/src/gui/painting/qcolor_p.cpp
index b1adf9f..d66990d 100644
--- a/src/gui/painting/qcolor_p.cpp
+++ b/src/gui/painting/qcolor_p.cpp
@@ -49,9 +49,6 @@
 #include "qrgb.h"
 #include "qstringlist.h"
 
-#if defined(Q_WS_WINCE)
-#include "qguifunctions_wince.h"
-#endif
 QT_BEGIN_NAMESPACE
 
 static inline int h2i(char hex)
@@ -290,33 +287,16 @@ static const int rgbTblSize = sizeof(rgbTbl) / sizeof(RGBData);
 
 #undef rgb
 
-QT_BEGIN_INCLUDE_NAMESPACE
-#include <stdlib.h>
-QT_END_INCLUDE_NAMESPACE
-
-#if defined(Q_C_CALLBACKS)
-extern "C" {
-#endif
-
-#ifdef Q_OS_WINCE
-static int __cdecl rgb_cmp(const void *d1, const void *d2)
-#else
-static int rgb_cmp(const void *d1, const void *d2)
-#endif
-{
-    return qstricmp(((RGBData *)d1)->name, ((RGBData *)d2)->name);
-}
-
-#if defined(Q_C_CALLBACKS)
-}
-#endif
+inline bool operator<(const char *name, const RGBData &data)
+{ return qstrcmp(name, data.name) < 0; }
+inline bool operator<(const RGBData &data, const char *name)
+{ return qstrcmp(data.name, name) < 0; }
 
-static bool get_named_rgb(const char *name, QRgb *rgb)
+static bool get_named_rgb(const char *name_no_space, QRgb *rgb)
 {
-    RGBData x;
-    x.name = name;
-    RGBData *r = (RGBData*)bsearch(&x, rgbTbl, rgbTblSize, sizeof(RGBData), rgb_cmp);
-    if (r) {
+    QByteArray name = QByteArray(name_no_space).toLower();
+    const RGBData *r = qBinaryFind(rgbTbl, rgbTbl + rgbTblSize, name.constData());
+    if (r != rgbTbl + rgbTblSize) {
         *rgb = r->value;
         return true;
     }