glx/drisw: add support for DRI2rendererQueryExtension

The extension is used by GLX_MESA_query_renderer, which
can be provided for by hardware and software drivers.

v2: Use designated initializers.
v3: Move drisw_query_renderer_*() to dri2_query_renderer.c

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>

src/glx/dri2_query_renderer.c

@@ -31,6 +31,7 @@
 #if defined(HAVE_DRI3)
 #include "dri3_priv.h"
 #endif
+#include "drisw_priv.h"
 
 #define __RENDERER(attrib) \
     { GLX_RENDERER_##attrib##_MESA, __DRI2_RENDERER_##attrib }
@@ -143,4 +144,43 @@ dri3_query_renderer_string(struct glx_screen *base, int attribute,
 }
 #endif /* HAVE_DRI3 */
 
+_X_HIDDEN int
+drisw_query_renderer_integer(struct glx_screen *base, int attribute,
+                             unsigned int *value)
+{
+   struct drisw_screen *const psc = (struct drisw_screen *) base;
+
+   /* Even though there are invalid values (and
+    * dri2_convert_glx_query_renderer_attribs may return -1), the higher level
+    * GLX code is required to perform the filtering.  Assume that we got a
+    * good value.
+    */
+   const int dri_attribute = dri2_convert_glx_query_renderer_attribs(attribute);
+
+   if (psc->rendererQuery == NULL)
+      return -1;
+
+   return psc->rendererQuery->queryInteger(psc->driScreen, dri_attribute,
+                                           value);
+}
+
+_X_HIDDEN int
+drisw_query_renderer_string(struct glx_screen *base, int attribute,
+                            const char **value)
+{
+   struct drisw_screen *const psc = (struct drisw_screen *) base;
+
+   /* Even though queryString only accepts a subset of the possible GLX
+    * queries, the higher level GLX code is required to perform the filtering.
+    * Assume that we got a good value.
+    */
+   const int dri_attribute = dri2_convert_glx_query_renderer_attribs(attribute);
+
+   if (psc->rendererQuery == NULL)
+      return -1;
+
+   return psc->rendererQuery->queryString(psc->driScreen, dri_attribute, value);
+}
+
+
 #endif /* GLX_DIRECT_RENDERING */

src/glx/drisw_glx.c

@@ -599,8 +599,8 @@ driOpenSwrast(void)
 static const struct glx_screen_vtable drisw_screen_vtable = {
    .create_context         = drisw_create_context,
    .create_context_attribs = drisw_create_context_attribs,
-   .query_renderer_integer = NULL,
-   .query_renderer_string  = NULL,
+   .query_renderer_integer = drisw_query_renderer_integer,
+   .query_renderer_string  = drisw_query_renderer_string,
 };
 
 static void
@@ -629,6 +629,14 @@ driswBindExtensions(struct drisw_screen *psc, const __DRIextension **extensions)
 	 psc->texBuffer = (__DRItexBufferExtension *) extensions[i];
 	 __glXEnableDirectExtension(&psc->base, "GLX_EXT_texture_from_pixmap");
       }
+      /* DRISW version 3 is also required because GLX_MESA_query_renderer
+       * requires GLX_ARB_create_context_profile.
+       */
+      if (psc->swrast->base.version >= 3
+          && strcmp(extensions[i]->name, __DRI2_RENDERER_QUERY) == 0) {
+         psc->rendererQuery = (__DRI2rendererQueryExtension *) extensions[i];
+         __glXEnableDirectExtension(&psc->base, "GLX_MESA_query_renderer");
+      }
    }
 }
 

src/glx/drisw_priv.h

@@ -45,6 +45,7 @@ struct drisw_screen
    const __DRIswrastExtension *swrast;
    const __DRItexBufferExtension *texBuffer;
    const __DRIcopySubBufferExtension *copySubBuffer;
+   const __DRI2rendererQueryExtension *rendererQuery;
 
    const __DRIconfig **driver_configs;
 
@@ -62,3 +63,10 @@ struct drisw_drawable
    XVisualInfo *visinfo;
    XImage *ximage;
 };
+
+_X_HIDDEN int
+drisw_query_renderer_integer(struct glx_screen *base, int attribute,
+                             unsigned int *value);
+_X_HIDDEN int
+drisw_query_renderer_string(struct glx_screen *base, int attribute,
+                            const char **value);