Optimize our GL extension checks to avoid mallocs.

We want to avoid any unnecessary mallocs when checking GL/GLX
extensions. The GL extension string can be quite long and contain
several hundred extensions. The old code forced one malloc for each
extension + 1 extra malloc for the extension string itself when
it was copied into the QByteArray.

Reviewed-by: Kim

1 files changed, 12 insertions, 12 deletions

diff --git a/src/opengl/qgl_x11.cpp b/src/opengl/qgl_x11.cpp
index a037282..9c3fc79 100644
--- a/src/opengl/qgl_x11.cpp
+++ b/src/opengl/qgl_x11.cpp
@@ -343,8 +343,8 @@ void* qglx_getProcAddress(const char* procName)
     static bool triedResolvingGlxGetProcAddress = false;
     if (!triedResolvingGlxGetProcAddress) {
         triedResolvingGlxGetProcAddress = true;
-        QList<QByteArray> glxExt = QByteArray(glXGetClientString(QX11Info::display(), GLX_EXTENSIONS)).split(' ');
-        if (glxExt.contains("GLX_ARB_get_proc_address")) {
+        QGLExtensionMatcher extensions(glXGetClientString(QX11Info::display(), GLX_EXTENSIONS));
+        if (extensions.match("GLX_ARB_get_proc_address")) {
 #if defined(Q_OS_LINUX) || defined(Q_OS_BSD4)
             void *handle = dlopen(NULL, RTLD_LAZY);
             if (handle) {
@@ -523,8 +523,8 @@ bool QGLContext::chooseContext(const QGLContext* shareContext)
         if (!d->gpm)
             return false;
     }
-    QList<QByteArray> glxExt = QByteArray(glXQueryExtensionsString(xinfo->display(), xinfo->screen())).split(' ');
-    if (glxExt.contains("GLX_SGI_video_sync")) {
+    QGLExtensionMatcher extensions(glXQueryExtensionsString(xinfo->display(), xinfo->screen()));
+    if (extensions.match("GLX_SGI_video_sync")) {
         if (d->glFormat.swapInterval() == -1)
             d->glFormat.setSwapInterval(0);
     } else {
@@ -630,8 +630,8 @@ void *QGLContext::tryVisual(const QGLFormat& f, int bufDepth)
     static bool useTranspExt = false;
     static bool useTranspExtChecked = false;
     if (f.plane() && !useTranspExtChecked && d->paintDevice) {
-        QByteArray estr(glXQueryExtensionsString(xinfo->display(), xinfo->screen()));
-        useTranspExt = estr.contains("GLX_EXT_visual_info");
+        QGLExtensionMatcher extensions(glXQueryExtensionsString(xinfo->display(), xinfo->screen()));
+        useTranspExt = extensions.match("GLX_EXT_visual_info");
         //# (A bit simplistic; that could theoretically be a substring)
         if (useTranspExt) {
             QByteArray cstr(glXGetClientString(xinfo->display(), GLX_VENDOR));
@@ -875,8 +875,8 @@ void QGLContext::swapBuffers() const
             static bool resolved = false;
             if (!resolved) {
                 const QX11Info *xinfo = qt_x11Info(d->paintDevice);
-                QList<QByteArray> glxExt = QByteArray(glXQueryExtensionsString(xinfo->display(), xinfo->screen())).split(' ');
-                if (glxExt.contains("GLX_SGI_video_sync")) {
+                QGLExtensionMatcher extensions(glXQueryExtensionsString(xinfo->display(), xinfo->screen()));
+                if (extensions.match("GLX_SGI_video_sync")) {
                     glXGetVideoSyncSGI =  (qt_glXGetVideoSyncSGI)qglx_getProcAddress("glXGetVideoSyncSGI");
                     glXWaitVideoSyncSGI = (qt_glXWaitVideoSyncSGI)qglx_getProcAddress("glXWaitVideoSyncSGI");
                 }
@@ -1107,8 +1107,8 @@ void *QGLContext::getProcAddress(const QString &proc) const
     if (resolved && !glXGetProcAddressARB)
         return 0;
     if (!glXGetProcAddressARB) {
-        QList<QByteArray> glxExt = QByteArray(glXGetClientString(QX11Info::display(), GLX_EXTENSIONS)).split(' ');
-        if (glxExt.contains("GLX_ARB_get_proc_address")) {
+        QGLExtensionMatcher extensions(glXGetClientString(QX11Info::display(), GLX_EXTENSIONS));
+        if (extensions.match("GLX_ARB_get_proc_address")) {
 #if defined(Q_OS_LINUX) || defined(Q_OS_BSD4)
             void *handle = dlopen(NULL, RTLD_LAZY);
             if (handle) {
@@ -1609,8 +1609,8 @@ static bool qt_resolveTextureFromPixmap(QPaintDevice *paintDevice)
             return false; // Can't use TFP without NPOT
         }
         const QX11Info *xinfo = qt_x11Info(paintDevice);
-        QList<QByteArray> glxExt = QByteArray(glXQueryExtensionsString(xinfo->display(), xinfo->screen())).split(' ');
-        if (glxExt.contains("GLX_EXT_texture_from_pixmap")) {
+        QGLExtensionMatcher extensions(glXQueryExtensionsString(xinfo->display(), xinfo->screen()));
+        if (extensions.match("GLX_EXT_texture_from_pixmap")) {
             glXBindTexImageEXT = (qt_glXBindTexImageEXT) qglx_getProcAddress("glXBindTexImageEXT");
             glXReleaseTexImageEXT = (qt_glXReleaseTexImageEXT) qglx_getProcAddress("glXReleaseTexImageEXT");
         }