From 71264ede6f3eb82c8dd3cb6ac566afefa502fd7e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?V=C3=ADctor=20Manuel=20J=C3=A1quez=20Leal?=
 <victorx.jaquez@intel.com>
Date: Thu, 18 Feb 2016 19:32:58 +0100
Subject: [PATCH] libs: context: ensure context formats

This patch ensures to get the formats, as filter does, available in the
decoder / encoder context.

The context fills up the array as soon it is created, otherwise the pipeline
could get stalled (perhaps this is a bug in my HSW backend).

https://bugzilla.gnome.org/show_bug.cgi?id=752958
---
 gst-libs/gst/vaapi/gstvaapicontext.c | 41 ++++++++++++++++++++++++++++
 gst-libs/gst/vaapi/gstvaapicontext.h |  5 ++++
 2 files changed, 46 insertions(+)

diff --git a/gst-libs/gst/vaapi/gstvaapicontext.c b/gst-libs/gst/vaapi/gstvaapicontext.c
index 4017c7bb1d..bf7a915e91 100644
--- a/gst-libs/gst/vaapi/gstvaapicontext.c
+++ b/gst-libs/gst/vaapi/gstvaapicontext.c
@@ -50,6 +50,18 @@
 /* Number of scratch surfaces beyond those used as reference */
 #define SCRATCH_SURFACES_COUNT (4)
 
+static gboolean
+ensure_formats (GstVaapiContext * context)
+{
+  if (G_LIKELY (context->formats))
+    return TRUE;
+
+  context->formats =
+      gst_vaapi_get_surface_formats (GST_VAAPI_OBJECT_DISPLAY (context),
+      context->va_config);
+  return (context->formats != NULL);
+}
+
 static void
 unref_surface_cb (GstVaapiSurface * surface)
 {
@@ -106,6 +118,11 @@ context_destroy (GstVaapiContext * context)
       GST_WARNING ("failed to destroy config 0x%08x", context->va_config);
     context->va_config = VA_INVALID_ID;
   }
+
+  if (context->formats) {
+    g_array_unref (context->formats);
+    context->formats = NULL;
+  }
 }
 
 static gboolean
@@ -325,6 +342,8 @@ gst_vaapi_context_init (GstVaapiContext * context,
   context->va_config = VA_INVALID_ID;
   context->reset_on_resize = TRUE;
   gst_vaapi_context_overlay_init (context);
+
+  context->formats = NULL;
 }
 
 static void
@@ -520,3 +539,25 @@ gst_vaapi_context_reset_on_resize (GstVaapiContext * context,
 
   context->reset_on_resize = reset_on_resize;
 }
+
+/**
+ * gst_vaapi_context_get_surface_formats:
+ * @context: a #GstVaapiContext
+ *
+ * Determines the set of supported formats by the surfaces associated
+ * to @context. The caller owns an extra reference of the resulting
+ * array of #GstVideoFormat elements, so it shall be released with
+ * g_array_unref after usage.
+ *
+ * Return value: (transfer full): the set of target formats supported
+ * by the surfaces in @context.
+ */
+GArray *
+gst_vaapi_context_get_surface_formats (GstVaapiContext * context)
+{
+  g_return_val_if_fail (context, NULL);
+
+  if (!ensure_formats (context))
+    return NULL;
+  return g_array_ref (context->formats);
+}
diff --git a/gst-libs/gst/vaapi/gstvaapicontext.h b/gst-libs/gst/vaapi/gstvaapicontext.h
index 19afc0626a..030419e131 100644
--- a/gst-libs/gst/vaapi/gstvaapicontext.h
+++ b/gst-libs/gst/vaapi/gstvaapicontext.h
@@ -109,6 +109,7 @@ struct _GstVaapiContext
   GPtrArray *overlays[2];
   guint overlay_id;
   gboolean reset_on_resize;
+  GArray *formats;
 };
 
 /**
@@ -149,6 +150,10 @@ void
 gst_vaapi_context_reset_on_resize (GstVaapiContext * context,
     gboolean reset_on_resize);
 
+G_GNUC_INTERNAL
+GArray *
+gst_vaapi_context_get_surface_formats (GstVaapiContext * context);
+
 G_END_DECLS
 
 #endif /* GST_VAAPI_CONTEXT_H */