From 4d4f3c3cc4647b1534e3bbe857ecc4f7ebf8b979 Mon Sep 17 00:00:00 2001
From: Tomasz Zajac <tomasz.zajac@motorolasolutions.com>
Date: Fri, 28 Oct 2016 08:47:01 +0200
Subject: [PATCH] sdp: Parse rtcp-fb media attributes

https://bugzilla.gnome.org/show_bug.cgi?id=769698
---
 gst-libs/gst/sdp/gstsdpmessage.c | 70 ++++++++++++++++++++++++++++++++
 1 file changed, 70 insertions(+)

diff --git a/gst-libs/gst/sdp/gstsdpmessage.c b/gst-libs/gst/sdp/gstsdpmessage.c
index 77192524e7..e5341db243 100644
--- a/gst-libs/gst/sdp/gstsdpmessage.c
+++ b/gst-libs/gst/sdp/gstsdpmessage.c
@@ -3270,6 +3270,73 @@ gst_sdp_parse_rtpmap (const gchar * rtpmap, gint * payload, gchar ** name,
   return TRUE;
 }
 
+/**
+ * gst_sdp_media_add_rtcp_fb_attributes_from_media:
+ * @media: a #GstSDPMedia
+ * @pt: payload type
+ * @caps: a #GstCaps
+ *
+ * Parse given @media for "rtcp-fb" attributes and add it to the @caps.
+ *
+ * Mapping of caps from SDP fields:
+ *
+ * a=rtcp-fb:(payload) (param1) [param2]...
+ *
+ * Returns: a #GstSDPResult.
+ */
+static GstSDPResult
+gst_sdp_media_add_rtcp_fb_attributes_from_media (const GstSDPMedia * media,
+    gint pt, GstCaps * caps)
+{
+  const gchar *rtcp_fb;
+  gchar *p, *to_free;
+  gint payload, i;
+  GstStructure *s;
+
+  g_return_val_if_fail (media != NULL, GST_SDP_EINVAL);
+  g_return_val_if_fail (caps != NULL && GST_IS_CAPS (caps), GST_SDP_EINVAL);
+
+  s = gst_caps_get_structure (caps, 0);
+
+  for (i = 0;; i++) {
+    gboolean all_formats = FALSE;
+
+    if ((rtcp_fb = gst_sdp_media_get_attribute_val_n (media,
+                "rtcp-fb", i)) == NULL)
+      break;
+
+    /* p is now of the format <payload> attr... */
+    to_free = p = g_strdup (rtcp_fb);
+
+    /* check if it applies to all formats */
+    if (*p == '*') {
+      p++;
+      all_formats = TRUE;
+    } else {
+      PARSE_INT (p, " ", payload);
+    }
+
+    if (all_formats || (payload != -1 && payload == pt)) {
+      gchar *tmp, *key;
+
+      SKIP_SPACES (p);
+
+      /* replace space with '-' */
+      key = g_strdup_printf ("rtcp-fb-%s", p);
+
+      for (tmp = key; (tmp = strchr (tmp, ' ')); ++tmp) {
+        *tmp = '-';
+      }
+
+      gst_structure_set (s, key, G_TYPE_BOOLEAN, TRUE, NULL);
+      GST_DEBUG ("adding caps: %s=TRUE", key);
+      g_free (key);
+    } else
+      g_free (to_free);
+  }
+  return GST_SDP_OK;
+}
+
 /**
  * gst_sdp_media_get_caps_from_media:
  * @media: a #GstSDPMedia
@@ -3439,6 +3506,9 @@ gst_sdp_media_get_caps_from_media (const GstSDPMedia * media, gint pt)
     }
   }
 
+  /* parse rtcp-fb: field */
+  gst_sdp_media_add_rtcp_fb_attributes_from_media (media, pt, caps);
+
   return caps;
 
   /* ERRORS */