gst/: Don't return FLOW_UNEXPECTED when a buffer is before the start of the stream (which might happen with large ID3...

Original commit message from CVS:
* gst/apetag/gsttagdemux.c: (gst_tag_demux_trim_buffer),
(gst_tag_demux_read_range):
* gst/id3demux/gstid3demux.c: (gst_id3demux_trim_buffer),
(gst_id3demux_read_range):
Don't return FLOW_UNEXPECTED when a buffer is before
the start of the stream (which might happen with
large ID3v2 tags if the tag reading was done pullrange
based and we then switched to push mode later on).
Fixes regression introduced by commit from June 29th.

1 files changed, 21 insertions, 6 deletions

diff --git a/gst/apetag/gsttagdemux.c b/gst/apetag/gsttagdemux.c
index 2aa23f44..4a18b07c 100644
--- a/gst/apetag/gsttagdemux.c
+++ b/gst/apetag/gsttagdemux.c
@@ -353,6 +353,10 @@ gst_tag_demux_remove_srcpad (GstTagDemux * demux)
   return res;
 };
 
+/* will return FALSE if buffer is beyond end of data; will return TRUE
+ * if buffer was trimmed successfully or didn't need trimming, but may
+ * also return TRUE and set *buf_ref to NULL if the buffer was before
+ * the start of the data */
 static gboolean
 gst_tag_demux_trim_buffer (GstTagDemux * tagdemux, GstBuffer ** buf_ref)
 {
@@ -377,7 +381,7 @@ gst_tag_demux_trim_buffer (GstTagDemux * tagdemux, GstBuffer ** buf_ref)
 
       if (out_offset >= v1tag_offset) {
         GST_DEBUG_OBJECT (tagdemux, "Buffer is past the end of the data");
-        goto no_out_buffer;
+        goto no_out_buffer_end;
       }
 
       if (out_offset + out_size > v1tag_offset) {
@@ -392,7 +396,7 @@ gst_tag_demux_trim_buffer (GstTagDemux * tagdemux, GstBuffer ** buf_ref)
     if (out_offset <= tagdemux->priv->strip_start) {
       if (out_offset + out_size <= tagdemux->priv->strip_start) {
         GST_DEBUG_OBJECT (tagdemux, "Buffer is before the start of the data");
-        goto no_out_buffer;
+        goto no_out_buffer_start;
       }
 
       trim_start = tagdemux->priv->strip_start - out_offset;
@@ -431,10 +435,18 @@ gst_tag_demux_trim_buffer (GstTagDemux * tagdemux, GstBuffer ** buf_ref)
 
   return TRUE;
 
-no_out_buffer:
-  gst_buffer_unref (buf);
-  *buf_ref = NULL;
-  return FALSE;
+no_out_buffer_end:
+  {
+    gst_buffer_unref (buf);
+    *buf_ref = NULL;
+    return FALSE;
+  }
+no_out_buffer_start:
+  {
+    gst_buffer_unref (buf);
+    *buf_ref = NULL;
+    return TRUE;
+  }
 }
 
 static void
@@ -1171,6 +1183,9 @@ gst_tag_demux_read_range (GstTagDemux * demux,
   if (ret == GST_FLOW_OK && *buffer) {
     if (!gst_tag_demux_trim_buffer (demux, buffer))
       goto read_beyond_end;
+
+    /* this should only happen in streaming mode */
+    g_assert (*buffer != NULL);
   }
 
   return ret;