mssdemux: implement snap seeking

Implement snap seek flags handling in stream_seek to allow the
parent class to handle it for us

https://bugzilla.gnome.org/show_bug.cgi?id=759158

ext/smoothstreaming/gstmssdemux.c

@@ -310,7 +310,8 @@ gst_mss_demux_stream_seek (GstAdaptiveDemuxStream * stream, gboolean forward,
 {
   GstMssDemuxStream *mssstream = (GstMssDemuxStream *) stream;
 
-  gst_mss_stream_seek (mssstream->manifest_stream, flags, ts, final_ts);
+  gst_mss_stream_seek (mssstream->manifest_stream, forward, flags, ts,
+      final_ts);
   return GST_FLOW_OK;
 }
 

ext/smoothstreaming/gstmssmanifest.c

@@ -1089,26 +1089,32 @@ gst_mss_stream_type_name (GstMssStreamType streamtype)
 /**
  * Seeks all streams to the fragment that contains the set time
  *
+ * @forward: if this is forward playback
  * @time: time in nanoseconds
  */
 void
-gst_mss_manifest_seek (GstMssManifest * manifest, guint64 time)
+gst_mss_manifest_seek (GstMssManifest * manifest, gboolean forward,
+    guint64 time)
 {
   GSList *iter;
 
   for (iter = manifest->streams; iter; iter = g_slist_next (iter)) {
-    gst_mss_stream_seek (iter->data, 0, time, NULL);
+    gst_mss_stream_seek (iter->data, forward, 0, time, NULL);
   }
 }
 
+#define SNAP_AFTER(forward,flags) \
+    ((forward && (flags & GST_SEEK_FLAG_SNAP_AFTER)) || \
+    (!forward && (flags & GST_SEEK_FLAG_SNAP_BEFORE)))
+
 /**
  * Seeks this stream to the fragment that contains the sample at time
  *
  * @time: time in nanoseconds
  */
 void
-gst_mss_stream_seek (GstMssStream * stream, GstSeekFlags flags, guint64 time,
+gst_mss_stream_seek (GstMssStream * stream, gboolean forward,
-    guint64 * final_time)
+    GstSeekFlags flags, guint64 time, guint64 * final_time)
 {
   GList *iter;
   guint64 timescale;
@@ -1118,48 +1124,58 @@ gst_mss_stream_seek (GstMssStream * stream, GstSeekFlags flags, guint64 time,
   time = gst_util_uint64_scale_round (time, timescale, GST_SECOND);
 
   GST_DEBUG ("Stream %s seeking to %" G_GUINT64_FORMAT, stream->url, time);
-
   for (iter = stream->fragments; iter; iter = g_list_next (iter)) {
-    GList *next = g_list_next (iter);
+    fragment = iter->data;
-    if (next) {
+    if (fragment->time + fragment->repetitions * fragment->duration > time) {
-      fragment = next->data;
+      stream->current_fragment = iter;
+      stream->fragment_repetition_index =
+          (time - fragment->time) / fragment->duration;
+      if (((time - fragment->time) % fragment->duration) == 0) {
 
-      if (fragment->time > time) {
+        /* for reverse playback, start from the previous fragment when we are
-        stream->current_fragment = iter;
+         * exactly at a limit */
-        break;
+        if (!forward)
-      }
+          stream->fragment_repetition_index--;
-    } else {
+      } else if (SNAP_AFTER (forward, flags))
-      fragment = iter->data;
+        stream->fragment_repetition_index++;
-      if (fragment->time + fragment->repetitions * fragment->duration > time) {
+
-        stream->current_fragment = iter;
+      if (stream->fragment_repetition_index == fragment->repetitions) {
-      } else {
+        /* move to the next one */
-        stream->current_fragment = NULL;        /* EOS */
+        stream->fragment_repetition_index = 0;
+        stream->current_fragment = g_list_next (iter);
+        fragment =
+            stream->current_fragment ? stream->current_fragment->data : NULL;
+
+      } else if (stream->fragment_repetition_index == -1) {
+        if (g_list_previous (iter)) {
+          stream->current_fragment = g_list_previous (iter);
+          fragment =
+              stream->current_fragment ? stream->current_fragment->data : NULL;
+          stream->fragment_repetition_index = fragment->repetitions - 1;
+        } else {
+          stream->fragment_repetition_index = 0;
+        }
       }
+
       break;
     }
-  }
 
-  /* position inside the repetitions */
-  if (stream->current_fragment) {
-    fragment = stream->current_fragment->data;
-    stream->fragment_repetition_index =
-        (time - fragment->time) / fragment->duration;
   }
 
   GST_DEBUG ("Stream %s seeked to fragment time %" G_GUINT64_FORMAT
-      " repetition %u", stream->url, fragment->time,
+      " repetition %u", stream->url,
+      fragment ? fragment->time : GST_CLOCK_TIME_NONE,
       stream->fragment_repetition_index);
   if (final_time) {
-    if (fragment)
+    if (fragment) {
-      *final_time =
+      *final_time = gst_util_uint64_scale_round (fragment->time +
-          fragment->time +
+          stream->fragment_repetition_index * fragment->duration,
-          stream->fragment_repetition_index * fragment->duration;
+          GST_SECOND, timescale);
-    else {
+    } else {
-      /* always stops on the last one */
+      GstMssStreamFragment *last_fragment = g_list_last (iter)->data;
-      GstMssStreamFragment *last_fragment = iter->data;
+      *final_time = gst_util_uint64_scale_round (last_fragment->time +
-      *final_time =
+          last_fragment->repetitions * last_fragment->duration,
-          last_fragment->time +
+          GST_SECOND, timescale);
-          last_fragment->repetitions * last_fragment->duration;
     }
   }
 }
@@ -1214,7 +1230,9 @@ gst_mss_stream_reload_fragments (GstMssStream * stream, xmlNodePtr streamIndex)
     g_list_free_full (stream->fragments, g_free);
     stream->fragments = g_list_reverse (builder.fragments);
     stream->current_fragment = stream->fragments;
-    gst_mss_stream_seek (stream, 0, current_gst_time, NULL);
+    /* TODO Verify how repositioning here works for reverse
+     * playback - it might start from the wrong fragment */
+    gst_mss_stream_seek (stream, TRUE, 0, current_gst_time, NULL);
   }
 }
 

ext/smoothstreaming/gstmssmanifest.h

@@ -44,7 +44,7 @@ GSList * gst_mss_manifest_get_streams (GstMssManifest * manifest);
 guint64 gst_mss_manifest_get_timescale (GstMssManifest * manifest);
 guint64 gst_mss_manifest_get_duration (GstMssManifest * manifest);
 GstClockTime gst_mss_manifest_get_gst_duration (GstMssManifest * manifest);
-void gst_mss_manifest_seek (GstMssManifest * manifest, guint64 time);
+void gst_mss_manifest_seek (GstMssManifest * manifest, gboolean forward, guint64 time);
 gboolean gst_mss_manifest_change_bitrate (GstMssManifest *manifest, guint64 bitrate);
 guint64 gst_mss_manifest_get_current_bitrate (GstMssManifest * manifest);
 gboolean gst_mss_manifest_is_live (GstMssManifest * manifest);
@@ -67,7 +67,7 @@ GstClockTime gst_mss_stream_get_fragment_gst_duration (GstMssStream * stream);
 gboolean gst_mss_stream_has_next_fragment (GstMssStream * stream);
 GstFlowReturn gst_mss_stream_advance_fragment (GstMssStream * stream);
 GstFlowReturn gst_mss_stream_regress_fragment (GstMssStream * stream);
-void gst_mss_stream_seek (GstMssStream * stream, GstSeekFlags flags, guint64 time, guint64 * final_time);
+void gst_mss_stream_seek (GstMssStream * stream, gboolean forward, GstSeekFlags flags, guint64 time, guint64 * final_time);
 const gchar * gst_mss_stream_get_lang (GstMssStream * stream);
 
 const gchar * gst_mss_stream_type_name (GstMssStreamType streamtype);