loader/dri3: add get_dri_screen() to the vtable

This allows querying the current active screen from the
loader's common code.

Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Signed-off-by: Martin Peres <martin.peres@linux.intel.com>

src/egl/drivers/dri2/platform_x11_dri3.c

@@ -103,6 +103,17 @@ egl_dri3_get_dri_context(struct loader_dri3_drawable *draw)
    return dri2_ctx->dri_context;
 }
 
+static __DRIscreen *
+egl_dri3_get_dri_screen(struct loader_dri3_drawable *draw)
+{
+   _EGLContext *ctx = _eglGetCurrentContext();
+   struct dri2_egl_context *dri2_ctx;
+   if (!ctx)
+      return NULL;
+   dri2_ctx = dri2_egl_context(ctx);
+   return dri2_egl_display(dri2_ctx->base.Resource.Display)->dri_screen;
+}
+
 static void
 egl_dri3_flush_drawable(struct loader_dri3_drawable *draw, unsigned flags)
 {
@@ -119,6 +130,7 @@ static struct loader_dri3_vtable egl_dri3_vtable = {
    .set_drawable_size = egl_dri3_set_drawable_size,
    .in_current_context = egl_dri3_in_current_context,
    .get_dri_context = egl_dri3_get_dri_context,
+   .get_dri_screen = egl_dri3_get_dri_screen,
    .flush_drawable = egl_dri3_flush_drawable,
    .show_fps = NULL,
 };

src/glx/dri3_glx.c

@@ -132,6 +132,16 @@ glx_dri3_get_dri_context(struct loader_dri3_drawable *draw)
    return (gc != &dummyContext) ? dri3Ctx->driContext : NULL;
 }
 
+static __DRIscreen *
+glx_dri3_get_dri_screen(struct loader_dri3_drawable *draw)
+{
+   struct glx_context *gc = __glXGetCurrentContext();
+   struct dri3_context *pcp = (struct dri3_context *) gc;
+   struct dri3_screen *psc = (struct dri3_screen *) pcp->base.psc;
+
+   return (gc != &dummyContext && psc) ? psc->driScreen : NULL;
+}
+
 static void
 glx_dri3_flush_drawable(struct loader_dri3_drawable *draw, unsigned flags)
 {
@@ -169,6 +179,7 @@ static struct loader_dri3_vtable glx_dri3_vtable = {
    .set_drawable_size = glx_dri3_set_drawable_size,
    .in_current_context = glx_dri3_in_current_context,
    .get_dri_context = glx_dri3_get_dri_context,
+   .get_dri_screen = glx_dri3_get_dri_screen,
    .flush_drawable = glx_dri3_flush_drawable,
    .show_fps = glx_dri3_show_fps,
 };

src/loader/loader_dri3_helper.h

@@ -103,6 +103,7 @@ struct loader_dri3_vtable {
    void (*set_drawable_size)(struct loader_dri3_drawable *, int, int);
    bool (*in_current_context)(struct loader_dri3_drawable *);
    __DRIcontext *(*get_dri_context)(struct loader_dri3_drawable *);
+   __DRIscreen *(*get_dri_screen)(struct loader_dri3_drawable *);
    void (*flush_drawable)(struct loader_dri3_drawable *, unsigned);
    void (*show_fps)(struct loader_dri3_drawable *, uint64_t);
 };