From e51fe6c1814c6048fd46e93b917bcf054aba3c31 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian.droege@collabora.co.uk>
Date: Fri, 20 Aug 2010 10:24:33 +0200
Subject: [PATCH] imagefreeze: Protect the flushing-seek variable by the
 srcpad's stream lock

This fixes a subtle race condition, that caused bufferalloc to fail
with wrong-state due to a seek but caused it to be not retried as
it should.
---
 gst/imagefreeze/gstimagefreeze.c | 9 ++++++++-
 gst/imagefreeze/gstimagefreeze.h | 3 ++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/gst/imagefreeze/gstimagefreeze.c b/gst/imagefreeze/gstimagefreeze.c
index 2b21906d9a..b8e99772c9 100644
--- a/gst/imagefreeze/gstimagefreeze.c
+++ b/gst/imagefreeze/gstimagefreeze.c
@@ -329,9 +329,16 @@ gst_image_freeze_sink_bufferalloc (GstPad * pad, guint64 offset, guint size,
   GST_OBJECT_UNLOCK (self);
 
   if (do_alloc) {
+    gboolean seeking = FALSE;
+
     do {
+      GST_PAD_STREAM_LOCK (self->srcpad);
       ret = gst_pad_alloc_buffer (self->srcpad, offset, size, caps, buf);
-    } while (ret == GST_FLOW_WRONG_STATE && g_atomic_int_get (&self->seeking));
+
+      seeking = ret == GST_FLOW_WRONG_STATE
+          && g_atomic_int_get (&self->seeking);
+      GST_PAD_STREAM_UNLOCK (self->srcpad);
+    } while (seeking);
 
     if (G_UNLIKELY (ret != GST_FLOW_OK))
       GST_ERROR_OBJECT (pad, "Allocating buffer failed: %s",
diff --git a/gst/imagefreeze/gstimagefreeze.h b/gst/imagefreeze/gstimagefreeze.h
index b9bc53f39c..fff8c2ea3e 100644
--- a/gst/imagefreeze/gstimagefreeze.h
+++ b/gst/imagefreeze/gstimagefreeze.h
@@ -56,7 +56,8 @@ struct _GstImageFreeze
 
   guint64 offset;
 
-  /* TRUE if currently doing a flushing seek */
+  /* TRUE if currently doing a flushing seek, protected
+   * by srcpad's stream lock */
   gint seeking;
 };