glcontext: egl: Stop comparing native surface pointer

This was noticed with wayland, sometimes the newly create native
handle can have the same pointer (even though its new). This lead
to unwanted errors or crash.

Fixes #927

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/1231>

2 files changed, 26 insertions, 14 deletions

diff --git a/gst-libs/gst/gl/egl/gstglcontext_egl.c b/gst-libs/gst/gl/egl/gstglcontext_egl.c
index bd83f88d8..24f2091f6 100644
--- a/gst-libs/gst/gl/egl/gstglcontext_egl.c
+++ b/gst-libs/gst/gl/egl/gstglcontext_egl.c
@@ -832,6 +832,18 @@ _create_context_with_flags (GstGLContextEGL * egl, EGLContext share_context,
       attribs);
 }
 
+static void
+gst_gl_context_egl_window_handle_changed_cb (GstGLContextEGL * egl,
+    GstGLWindow * window)
+{
+  if (egl->egl_surface != EGL_NO_SURFACE) {
+    if (!eglDestroySurface (egl->egl_display, egl->egl_surface))
+      GST_WARNING_OBJECT (egl, "Failed to destroy old window surface: %s",
+          gst_egl_get_error_string (eglGetError ()));
+    egl->egl_surface = EGL_NO_SURFACE;
+  }
+}
+
 static gboolean
 gst_gl_context_egl_create_context (GstGLContext * context,
     GstGLAPI gl_api, GstGLContext * other_context, GError ** error)
@@ -1112,8 +1124,6 @@ gst_gl_context_egl_create_context (GstGLContext * context,
     egl->egl_surface =
         eglCreateWindowSurface (egl->egl_display, egl->egl_config,
         (EGLNativeWindowType) window_handle, attrs);
-    /* Store window handle for later comparison */
-    egl->window_handle = window_handle;
   } else if (!gst_gl_check_extension ("EGL_KHR_surfaceless_context",
           egl->egl_exts)) {
     EGLint surface_attrib[7];
@@ -1152,8 +1162,12 @@ gst_gl_context_egl_create_context (GstGLContext * context,
   egl->egl_major = egl_major;
   egl->egl_minor = egl_minor;
 
-  if (window)
+  if (window) {
+    egl->window_handle_signal = g_signal_connect_swapped (window,
+        "window-handle-changed",
+        G_CALLBACK (gst_gl_context_egl_window_handle_changed_cb), egl);
     gst_object_unref (window);
+  }
 
   return TRUE;
 
@@ -1168,8 +1182,15 @@ static void
 gst_gl_context_egl_destroy_context (GstGLContext * context)
 {
   GstGLContextEGL *egl;
+  GstGLWindow *window;
 
   egl = GST_GL_CONTEXT_EGL (context);
+  window = gst_gl_context_get_window (context);
+
+  if (window && egl->window_handle_signal) {
+    g_signal_handler_disconnect (window, egl->window_handle_signal);
+    egl->window_handle_signal = 0;
+  }
 
   gst_gl_context_egl_activate (context, FALSE);
 
@@ -1182,7 +1203,6 @@ gst_gl_context_egl_destroy_context (GstGLContext * context)
     eglDestroyContext (egl->egl_display, egl->egl_context);
     egl->egl_context = NULL;
   }
-  egl->window_handle = 0;
 
   eglReleaseThread ();
 
@@ -1212,7 +1232,7 @@ gst_gl_context_egl_activate (GstGLContext * context, gboolean activate)
       handle = gst_gl_window_get_window_handle (window);
       gst_object_unref (window);
     }
-    if (handle && handle != egl->window_handle) {
+    if (handle && (egl->egl_surface == EGL_NO_SURFACE)) {
 #if GST_GL_HAVE_WINDOW_WINRT && defined (EGL_ANGLE_SURFACE_RENDER_TO_BACK_BUFFER)
       const EGLint attrs[] = {
         /* EGL_ANGLE_SURFACE_RENDER_TO_BACK_BUFFER is an optimization that can
@@ -1226,15 +1246,6 @@ gst_gl_context_egl_activate (GstGLContext * context, gboolean activate)
       GST_DEBUG_OBJECT (context,
           "Handle changed (have:%p, now:%p), switching surface",
           (void *) egl->window_handle, (void *) handle);
-      if (egl->egl_surface) {
-        result = eglDestroySurface (egl->egl_display, egl->egl_surface);
-        egl->egl_surface = EGL_NO_SURFACE;
-        if (!result) {
-          GST_ERROR_OBJECT (context, "Failed to destroy old window surface: %s",
-              gst_egl_get_error_string (eglGetError ()));
-          goto done;
-        }
-      }
       egl->egl_surface =
           eglCreateWindowSurface (egl->egl_display, egl->egl_config,
           (EGLNativeWindowType) handle, attrs);
diff --git a/gst-libs/gst/gl/egl/gstglcontext_egl.h b/gst-libs/gst/gl/egl/gstglcontext_egl.h
index 644731f36..4687585ac 100644
--- a/gst-libs/gst/gl/egl/gstglcontext_egl.h
+++ b/gst-libs/gst/gl/egl/gstglcontext_egl.h
@@ -67,6 +67,7 @@ struct _GstGLContextEGL
 
   /* Cached handle */
   guintptr window_handle;
+  gulong window_handle_signal;
 
   GstStructure *requested_config;
 };