[cogl/fosdem-2012: 3/5] Move the add_swap_buffers_callback functions out of the winsys

[Neil Roberts <nroberts src gnome org>]

commit 148f09532d328d2d47b5bcd0ff58a05c9a513540
Author: Neil Roberts <neil linux intel com>
Date:   Mon Dec 19 19:26:44 2011 +0000

    Move the add_swap_buffers_callback functions out of the winsys
    
    Instead of having each winsys implement its own list of callbacks the
    list is now just attached directly to the CoglOnscreen using code in
    cogl-onscreen.c. The winsys's can invoke this list of callbacks by
    calling _cogl_onscreen_notify_swap_buffers(). All of the winsys's
    would probably have a very similar implementation for this anyway and
    I don't think it makes much sense to try and save the cost of a list
    pointer in the CoglOnscreen struct.

 cogl/cogl-onscreen-private.h      |   18 +++++++++++
 cogl/cogl-onscreen.c              |   46 +++++++++++++++++++---------
 cogl/winsys/cogl-winsys-glx.c     |   60 +------------------------------------
 cogl/winsys/cogl-winsys-private.h |    9 -----
 4 files changed, 50 insertions(+), 83 deletions(-)
---
diff --git a/cogl/cogl-onscreen-private.h b/cogl/cogl-onscreen-private.h
index be789a5..1666b26 100644
--- a/cogl/cogl-onscreen-private.h
+++ b/cogl/cogl-onscreen-private.h
@@ -32,6 +32,19 @@
 #include <windows.h>
 #endif
 
+typedef struct _CoglSwapBuffersNotifyEntry CoglSwapBuffersNotifyEntry;
+
+COGL_TAILQ_HEAD (CoglSwapBuffersNotifyList, CoglSwapBuffersNotifyEntry);
+
+struct _CoglSwapBuffersNotifyEntry
+{
+  COGL_TAILQ_ENTRY (CoglSwapBuffersNotifyEntry) list_node;
+
+  CoglSwapBuffersNotify callback;
+  void *user_data;
+  unsigned int id;
+};
+
 struct _CoglOnscreen
 {
   CoglFramebuffer  _parent;
@@ -48,6 +61,8 @@ struct _CoglOnscreen
 
   gboolean swap_throttled;
 
+  CoglSwapBuffersNotifyList swap_callbacks;
+
   void *winsys;
 };
 CoglOnscreen *
@@ -60,4 +75,7 @@ _cogl_framebuffer_winsys_update_size (CoglFramebuffer *framebuffer,
 GQuark
 _cogl_object_onscreen_get_type (void);
 
+void
+_cogl_onscreen_notify_swap_buffers (CoglOnscreen *onscreen);
+
 #endif /* __COGL_ONSCREEN_PRIVATE_H */
diff --git a/cogl/cogl-onscreen.c b/cogl/cogl-onscreen.c
index 4eff256..708a441 100644
--- a/cogl/cogl-onscreen.c
+++ b/cogl/cogl-onscreen.c
@@ -42,6 +42,8 @@ _cogl_onscreen_init_from_template (CoglOnscreen *onscreen,
 {
   CoglFramebuffer *framebuffer = COGL_FRAMEBUFFER (onscreen);
 
+  COGL_TAILQ_INIT (&onscreen->swap_callbacks);
+
   framebuffer->config = onscreen_template->config;
   cogl_object_ref (framebuffer->config.swap_chain);
 }
@@ -257,18 +259,16 @@ cogl_framebuffer_add_swap_buffers_callback (CoglFramebuffer *framebuffer,
                                             void *user_data)
 {
   CoglOnscreen *onscreen = COGL_ONSCREEN (framebuffer);
-  const CoglWinsysVtable *winsys = _cogl_framebuffer_get_winsys (framebuffer);
+  CoglSwapBuffersNotifyEntry *entry = g_slice_new0 (CoglSwapBuffersNotifyEntry);
+  static int next_swap_buffers_callback_id = 0;
 
-  /* Should this just be cogl_onscreen API instead? */
-  _COGL_RETURN_VAL_IF_FAIL (framebuffer->type == COGL_FRAMEBUFFER_TYPE_ONSCREEN, 0);
+  entry->callback = callback;
+  entry->user_data = user_data;
+  entry->id = next_swap_buffers_callback_id++;
 
-  /* This should only be called when
-     COGL_WINSYS_FEATURE_SWAP_BUFFERS_EVENT is advertised */
-  _COGL_RETURN_VAL_IF_FAIL (winsys->onscreen_add_swap_buffers_callback != NULL, 0);
+  COGL_TAILQ_INSERT_TAIL (&onscreen->swap_callbacks, entry, list_node);
 
-  return winsys->onscreen_add_swap_buffers_callback (onscreen,
-                                                     callback,
-                                                     user_data);
+  return entry->id;
 }
 
 void
@@ -276,13 +276,17 @@ cogl_framebuffer_remove_swap_buffers_callback (CoglFramebuffer *framebuffer,
                                                unsigned int id)
 {
   CoglOnscreen *onscreen = COGL_ONSCREEN (framebuffer);
-  const CoglWinsysVtable *winsys = _cogl_framebuffer_get_winsys (framebuffer);
+  CoglSwapBuffersNotifyEntry *entry;
 
-  /* This should only be called when
-     COGL_WINSYS_FEATURE_SWAP_BUFFERS_EVENT is advertised */
-  _COGL_RETURN_IF_FAIL (winsys->onscreen_remove_swap_buffers_callback != NULL);
-
-  winsys->onscreen_remove_swap_buffers_callback (onscreen, id);
+  COGL_TAILQ_FOREACH (entry, &onscreen->swap_callbacks, list_node)
+    {
+      if (entry->id == id)
+        {
+          COGL_TAILQ_REMOVE (&onscreen->swap_callbacks, entry, list_node);
+          g_slice_free (CoglSwapBuffersNotifyEntry, entry);
+          break;
+        }
+    }
 }
 
 void
@@ -331,6 +335,18 @@ cogl_onscreen_hide (CoglOnscreen *onscreen)
 }
 
 void
+_cogl_onscreen_notify_swap_buffers (CoglOnscreen *onscreen)
+{
+  CoglSwapBuffersNotifyEntry *entry, *tmp;
+
+  COGL_TAILQ_FOREACH_SAFE (entry,
+                           &onscreen->swap_callbacks,
+                           list_node,
+                           tmp)
+    entry->callback (COGL_FRAMEBUFFER (onscreen), entry->user_data);
+}
+
+void
 _cogl_framebuffer_winsys_update_size (CoglFramebuffer *framebuffer,
                                       int width, int height)
 {
diff --git a/cogl/winsys/cogl-winsys-glx.c b/cogl/winsys/cogl-winsys-glx.c
index ccc746a..362f5ef 100644
--- a/cogl/winsys/cogl-winsys-glx.c
+++ b/cogl/winsys/cogl-winsys-glx.c
@@ -83,13 +83,6 @@ typedef struct _CoglOnscreenGLX
   GList *swap_callbacks;
 } CoglOnscreenGLX;
 
-typedef struct _CoglSwapBuffersNotifyEntry
-{
-  CoglSwapBuffersNotify callback;
-  void *user_data;
-  unsigned int id;
-} CoglSwapBuffersNotifyEntry;
-
 typedef struct _CoglTexturePixmapGLX
 {
   GLXPixmap glx_pixmap;
@@ -170,19 +163,11 @@ static void
 notify_swap_buffers (CoglContext *context, GLXDrawable drawable)
 {
   CoglOnscreen *onscreen = find_onscreen_for_xid (context, (guint32)drawable);
-  CoglOnscreenGLX *glx_onscreen;
-  GList *l;
 
   if (!onscreen)
     return;
 
-  glx_onscreen = onscreen->winsys;
-
-  for (l = glx_onscreen->swap_callbacks; l; l = l->next)
-    {
-      CoglSwapBuffersNotifyEntry *entry = l->data;
-      entry->callback (COGL_FRAMEBUFFER (onscreen), entry->user_data);
-    }
+  _cogl_onscreen_notify_swap_buffers (onscreen);
 }
 
 static CoglFilterReturn
@@ -1359,45 +1344,6 @@ _cogl_winsys_onscreen_x11_get_window_xid (CoglOnscreen *onscreen)
   return xlib_onscreen->xwin;
 }
 
-static unsigned int
-_cogl_winsys_onscreen_add_swap_buffers_callback (CoglOnscreen *onscreen,
-                                                 CoglSwapBuffersNotify callback,
-                                                 void *user_data)
-{
-  CoglOnscreenGLX *glx_onscreen = onscreen->winsys;
-  CoglSwapBuffersNotifyEntry *entry = g_slice_new0 (CoglSwapBuffersNotifyEntry);
-  static int next_swap_buffers_callback_id = 0;
-
-  entry->callback = callback;
-  entry->user_data = user_data;
-  entry->id = next_swap_buffers_callback_id++;
-
-  glx_onscreen->swap_callbacks =
-    g_list_prepend (glx_onscreen->swap_callbacks, entry);
-
-  return entry->id;
-}
-
-static void
-_cogl_winsys_onscreen_remove_swap_buffers_callback (CoglOnscreen *onscreen,
-                                                    unsigned int id)
-{
-  CoglOnscreenGLX *glx_onscreen = onscreen->winsys;
-  GList *l;
-
-  for (l = glx_onscreen->swap_callbacks; l; l = l->next)
-    {
-      CoglSwapBuffersNotifyEntry *entry = l->data;
-      if (entry->id == id)
-        {
-          g_slice_free (CoglSwapBuffersNotifyEntry, entry);
-          glx_onscreen->swap_callbacks =
-            g_list_delete_link (glx_onscreen->swap_callbacks, l);
-          return;
-        }
-    }
-}
-
 static void
 _cogl_winsys_onscreen_update_swap_throttled (CoglOnscreen *onscreen)
 {
@@ -2052,10 +1998,6 @@ static CoglWinsysVtable _cogl_winsys_vtable =
       _cogl_winsys_onscreen_update_swap_throttled,
     .onscreen_x11_get_window_xid =
       _cogl_winsys_onscreen_x11_get_window_xid,
-    .onscreen_add_swap_buffers_callback =
-      _cogl_winsys_onscreen_add_swap_buffers_callback,
-    .onscreen_remove_swap_buffers_callback =
-      _cogl_winsys_onscreen_remove_swap_buffers_callback,
     .onscreen_set_visibility = _cogl_winsys_onscreen_set_visibility,
 
     .poll_get_info = _cogl_winsys_poll_get_info,
diff --git a/cogl/winsys/cogl-winsys-private.h b/cogl/winsys/cogl-winsys-private.h
index 3c235ed..871ad0a 100644
--- a/cogl/winsys/cogl-winsys-private.h
+++ b/cogl/winsys/cogl-winsys-private.h
@@ -142,15 +142,6 @@ typedef struct _CoglWinsysVtable
   (*onscreen_win32_get_window) (CoglOnscreen *onscreen);
 #endif
 
-  unsigned int
-  (*onscreen_add_swap_buffers_callback) (CoglOnscreen *onscreen,
-                                         CoglSwapBuffersNotify callback,
-                                         void *user_data);
-
-  void
-  (*onscreen_remove_swap_buffers_callback) (CoglOnscreen *onscreen,
-                                            unsigned int id);
-
   void
   (*poll_get_info) (CoglContext *context,
                     CoglPollFD **poll_fds,