DRI2: add config query extension

Add a new DRI2 configuration query extension.  Allows for DRI2 client
code to query for common DRI2 configuration options.

include/GL/internal/dri_interface.h

@@ -812,4 +812,18 @@ struct __DRIimageLookupExtensionRec {
 				  void *loaderPrivate);
 };
 
+/**
+ * This extension allows for common DRI2 options
+ */
+#define __DRI2_CONFIG_QUERY "DRI_CONFIG_QUERY"
+#define __DRI2_CONFIG_QUERY_VERSION 1
+
+typedef struct __DRI2configQueryExtensionRec __DRI2configQueryExtension;
+struct __DRI2configQueryExtensionRec {
+   __DRIextension base;
+
+   int (*configQueryb)(__DRIscreen *screen, const char *var, GLboolean *val);
+   int (*configQueryi)(__DRIscreen *screen, const char *var, GLint *val);
+   int (*configQueryf)(__DRIscreen *screen, const char *var, GLfloat *val);
+};
 #endif

src/glx/dri_common.c

@@ -403,6 +403,11 @@ dri2BindExtensions(__GLXscreenConfigs *psc)
 	 /* internal driver extension, no GL extension exposed */
       }
 #endif
+
+#ifdef __DRI2_CONFIG_QUERY
+      if ((strcmp(extensions[i]->name, __DRI2_CONFIG_QUERY) == 0))
+	 psc->config = (__DRI2configQueryExtension *) extensions[i];
+#endif
    }
 }
 

src/glx/glxclient.h

@@ -549,6 +549,10 @@ struct __GLXscreenConfigsRec
    const __DRI2flushExtension *f;
 #endif
 
+#ifdef __DRI2_CONFIG_QUERY
+   const __DRI2configQueryExtension *config;
+#endif
+
 #endif
 
     /**

src/mesa/drivers/dri/common/dri_util.c

@@ -467,6 +467,41 @@ dri2CreateNewDrawable(__DRIscreen *screen,
     return pdraw;
 }
 
+static int
+dri2ConfigQueryb(__DRIscreen *screen, const char *var, GLboolean *val)
+{
+   if (!driCheckOption(&screen->optionCache, var, DRI_BOOL))
+      return -1;
+
+   *val = driQueryOptionb(&screen->optionCache, var);
+
+   return 0;
+}
+
+static int
+dri2ConfigQueryi(__DRIscreen *screen, const char *var, GLint *val)
+{
+   if (!driCheckOption(&screen->optionCache, var, DRI_INT) &&
+       !driCheckOption(&screen->optionCache, var, DRI_ENUM))
+      return -1;
+
+    *val = driQueryOptioni(&screen->optionCache, var);
+
+    return 0;
+}
+
+static int
+dri2ConfigQueryf(__DRIscreen *screen, const char *var, GLfloat *val)
+{
+   if (!driCheckOption(&screen->optionCache, var, DRI_FLOAT))
+      return -1;
+
+    *val = driQueryOptionf(&screen->optionCache, var);
+
+    return 0;
+}
+
+
 static void dri_get_drawable(__DRIdrawable *pdp)
 {
     pdp->refcount++;
@@ -739,6 +774,7 @@ dri2CreateNewScreen(int scrn, int fd,
     static const __DRIextension *emptyExtensionList[] = { NULL };
     __DRIscreen *psp;
     drmVersionPtr version;
+    driOptionCache options;
 
     if (driDriverAPI.InitScreen2 == NULL)
         return NULL;
@@ -771,6 +807,9 @@ dri2CreateNewScreen(int scrn, int fd,
 
     psp->DriverAPI = driDriverAPI;
 
+    driParseOptionInfo(&options, __dri2ConfigOptions, __dri2NConfigOptions);
+    driParseConfigFiles(&psp->optionCache, &options, psp->myNum, "dri2");
+
     return psp;
 }
 
@@ -813,6 +852,13 @@ const __DRIdri2Extension driDRI2Extension = {
     dri2CreateNewContext,
 };
 
+const __DRI2configQueryExtension dri2ConfigQueryExtension = {
+   { __DRI2_CONFIG_QUERY, __DRI2_CONFIG_QUERY_VERSION },
+   dri2ConfigQueryb,
+   dri2ConfigQueryi,
+   dri2ConfigQueryf,
+};
+
 static int
 driFrameTracking(__DRIdrawable *drawable, GLboolean enable)
 {

src/mesa/drivers/dri/common/dri_util.h

@@ -51,6 +51,7 @@
 #include <drm.h>
 #include <drm_sarea.h>
 #include <xf86drm.h>
+#include "xmlconfig.h"
 #include "main/glheader.h"
 #include "GL/internal/glcore.h"
 #include "GL/internal/dri_interface.h"
@@ -70,6 +71,7 @@ extern const __DRIcopySubBufferExtension driCopySubBufferExtension;
 extern const __DRIswapControlExtension driSwapControlExtension;
 extern const __DRIframeTrackingExtension driFrameTrackingExtension;
 extern const __DRImediaStreamCounterExtension driMediaStreamCounterExtension;
+extern const __DRI2configQueryExtension dri2ConfigQueryExtension;
 
 /**
  * Used by DRI_VALIDATE_DRAWABLE_INFO
@@ -527,6 +529,8 @@ struct __DRIscreenRec {
 
     /* The lock actually in use, old sarea or DRI2 */
     drmLock *lock;
+
+    driOptionCache optionCache;
 };
 
 extern void

src/mesa/drivers/dri/intel/intel_screen.c

@@ -225,6 +225,7 @@ static const __DRIextension *intelScreenExtensions[] = {
     &intelTexBufferExtension.base,
     &intelFlushExtension.base,
     &intelImageExtension.base,
+    &dri2ConfigQueryExtension.base,
     NULL
 };
 

src/mesa/drivers/dri/nouveau/nouveau_screen.c

@@ -236,6 +236,7 @@ static const struct __DRItexBufferExtensionRec nouveau_texbuffer_extension = {
 static const __DRIextension *nouveau_screen_extensions[] = {
     &nouveau_flush_extension.base,
     &nouveau_texbuffer_extension.base,
+    &dri2ConfigQueryExtension.base,
     NULL
 };
 

src/mesa/drivers/dri/radeon/radeon_screen.c

@@ -1235,6 +1235,8 @@ radeonCreateScreen( __DRIscreen *sPriv )
    screen->extensions[i++] = &r600texOffsetExtension.base;
 #endif
 
+   screen->extensions[i++] = &dri2ConfigQueryExtension.base;
+
    screen->extensions[i++] = NULL;
    sPriv->extensions = screen->extensions;
 

src/mesa/drivers/dri/radeon/radeon_screen.h

@@ -105,7 +105,7 @@ typedef struct radeon_screen {
    /* Configuration cache with default values for all contexts */
    driOptionCache optionCache;
 
-   const __DRIextension *extensions[16];
+   const __DRIextension *extensions[17];
 
    int num_gb_pipes;
    int num_z_pipes;