[RFC 6/9] egl_dri2: implement get_buffers and swap_buffers in drm platform

[Ander Conselvan de Oliveira]

From: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira at intel.com>

---
 src/egl/drivers/dri2/platform_drm.c |  153 ++++++++++++++++++++++++++++++++++-
 1 files changed, 152 insertions(+), 1 deletions(-)

diff --git a/src/egl/drivers/dri2/platform_drm.c b/src/egl/drivers/dri2/platform_drm.c
index 6ec63c1..bafaa22 100644
--- a/src/egl/drivers/dri2/platform_drm.c
+++ b/src/egl/drivers/dri2/platform_drm.c
@@ -71,6 +71,8 @@ dri2_create_surface(_EGLDriver *drv, _EGLDisplay *disp, EGLint type,
       dri2_surf->base.Width =  surf->base.width;
       dri2_surf->base.Height = surf->base.height;
 
+      surf->dri_private = dri2_surf;
+
       break;
    default:
       goto cleanup_surf;
@@ -125,10 +127,155 @@ dri2_destroy_surface(_EGLDriver *drv, _EGLDisplay *disp, _EGLSurface *surf)
    return EGL_TRUE;
 }
 
+static void
+dri2_process_back_buffer(struct dri2_egl_surface *dri2_surf, unsigned format)
+{
+   struct dri2_egl_display *dri2_dpy =
+      dri2_egl_display(dri2_surf->base.Resource.Display);
+
+   (void) format;
+
+   switch (dri2_surf->base.Type) {
+   case EGL_WINDOW_BIT:
+      /* allocate a front buffer for our double-buffered window*/
+      if (dri2_surf->dri_buffers[__DRI_BUFFER_FRONT_LEFT] != NULL)
+         break;
+      dri2_surf->dri_buffers[__DRI_BUFFER_FRONT_LEFT] =
+         dri2_dpy->dri2->allocateBuffer(dri2_dpy->dri_screen,
+               __DRI_BUFFER_FRONT_LEFT, format,
+               dri2_surf->base.Width, dri2_surf->base.Height);
+      break;
+   default:
+      break;
+   }
+}
+
+static inline void
+pointer_swap(const void **p1, const void **p2)
+{
+   const void *tmp = *p1;
+   *p1 = *p2;
+   *p2 = tmp;
+}
+
+static __DRIbuffer *
+dri2_get_buffers_with_format(__DRIdrawable * driDrawable,
+			     int *width, int *height,
+			     unsigned int *attachments, int count,
+			     int *out_count, void *loaderPrivate)
+{
+   struct dri2_egl_surface *dri2_surf = loaderPrivate;
+   struct dri2_egl_display *dri2_dpy =
+      dri2_egl_display(dri2_surf->base.Resource.Display);
+   int i;
+
+   dri2_surf->buffer_count = 0;
+   for (i = 0; i < 2*count; i+=2) {
+      assert(attachments[i] < __DRI_BUFFER_COUNT);
+      assert(dri2_surf->buffer_count < 5);
+
+      if (dri2_surf->dri_buffers[attachments[i]] == NULL) {
+
+         dri2_surf->dri_buffers[attachments[i]] =
+            dri2_dpy->dri2->allocateBuffer(dri2_dpy->dri_screen,
+                  attachments[i], attachments[i+1],
+                  dri2_surf->base.Width, dri2_surf->base.Height);
+
+         if (!dri2_surf->dri_buffers[attachments[i]])
+            continue;
+
+         if (attachments[i] == __DRI_BUFFER_BACK_LEFT)
+            dri2_process_back_buffer(dri2_surf, attachments[i+1]);
+      }
+
+      memcpy(&dri2_surf->buffers[dri2_surf->buffer_count],
+             dri2_surf->dri_buffers[attachments[i]],
+             sizeof(__DRIbuffer));
+
+      dri2_surf->buffer_count++;
+   }
+
+   assert(dri2_surf->dri_buffers[__DRI_BUFFER_BACK_LEFT]);
+
+   *out_count = dri2_surf->buffer_count;
+   if (dri2_surf->buffer_count == 0)
+      return NULL;
+
+   *width = dri2_surf->base.Width;
+   *height = dri2_surf->base.Height;
+
+   return dri2_surf->buffers;
+}
+
+static __DRIbuffer *
+dri2_get_buffers(__DRIdrawable * driDrawable,
+		 int *width, int *height,
+		 unsigned int *attachments, int count,
+		 int *out_count, void *loaderPrivate)
+{
+   unsigned int *attachments_with_format;
+   __DRIbuffer *buffer;
+   const unsigned int format = 32;
+   int i;
+
+   attachments_with_format = calloc(count * 2, sizeof(unsigned int));
+   if (!attachments_with_format) {
+      *out_count = 0;
+      return NULL;
+   }
+
+   for (i = 0; i < count; ++i) {
+      attachments_with_format[2*i] = attachments[i];
+      attachments_with_format[2*i + 1] = format;
+   }
+
+   buffer =
+      dri2_get_buffers_with_format(driDrawable,
+				   width, height,
+				   attachments_with_format, count,
+				   out_count, loaderPrivate);
+
+   free(attachments_with_format);
+
+   return buffer;
+}
+
+static void
+dri2_flush_front_buffer(__DRIdrawable * driDrawable, void *loaderPrivate)
+{
+   (void) driDrawable;
+   (void) loaderPrivate;
+}
+
 static EGLBoolean
 dri2_swap_buffers(_EGLDriver *drv, _EGLDisplay *disp, _EGLSurface *draw)
 {
-   return EGL_FALSE;
+   struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
+   struct dri2_egl_surface *dri2_surf = dri2_egl_surface(draw);
+   struct dri2_egl_driver *dri2_drv = dri2_egl_driver(drv);
+
+   if (dri2_surf->base.Type == EGL_WINDOW_BIT) {
+      pointer_swap(
+            (const void **) &dri2_surf->dri_buffers[__DRI_BUFFER_FRONT_LEFT],
+            (const void **) &dri2_surf->dri_buffers[__DRI_BUFFER_BACK_LEFT]);
+
+      dri2_surf->dri_buffers[__DRI_BUFFER_FRONT_LEFT]->attachment =
+         __DRI_BUFFER_FRONT_LEFT;
+      dri2_surf->dri_buffers[__DRI_BUFFER_BACK_LEFT]->attachment =
+        __DRI_BUFFER_BACK_LEFT;
+   }
+
+   _EGLContext *ctx;
+   if (dri2_drv->glFlush) {
+      ctx = _eglGetCurrentContext();
+      if (ctx && ctx->DrawSurface == &dri2_surf->base)
+         dri2_drv->glFlush();
+   }
+
+   (*dri2_dpy->flush->flush)(dri2_surf->dri_drawable);
+   (*dri2_dpy->flush->invalidate)(dri2_surf->dri_drawable);
+
+   return EGL_TRUE;
 }
 
 
@@ -242,6 +389,10 @@ dri2_initialize_drm(_EGLDriver *drv, _EGLDisplay *disp)
    dri2_dpy->gbm_dri->lookup_image = dri2_lookup_egl_image;
    dri2_dpy->gbm_dri->lookup_user_data = disp;
 
+   dri2_dpy->gbm_dri->get_buffers = dri2_get_buffers;
+   dri2_dpy->gbm_dri->flush_front_buffer = dri2_flush_front_buffer;
+   dri2_dpy->gbm_dri->get_buffers_with_format = dri2_get_buffers_with_format;
+
    dri2_setup_screen(disp);
 
    for (i = 0; dri2_dpy->driver_configs[i]; i++)
-- 
1.7.4.1