v4l2codecs: pool: Create new buffer when pool is empty

This simply create an empty GstBuffer when the pool is empty. This way it's up
to the allocator to grow or wait if we ran out of memory.

diff --git a/sys/v4l2codecs/gstv4l2codecpool.c b/sys/v4l2codecs/gstv4l2codecpool.c
index 60795ff..69a01d4 100644 (file)
--- a/sys/v4l2codecs/gstv4l2codecpool.c
+++ b/sys/v4l2codecs/gstv4l2codecpool.c
@@ -33,22 +33,37 @@ struct _GstV4l2CodecPool
 
 G_DEFINE_TYPE (GstV4l2CodecPool, gst_v4l2_codec_pool, GST_TYPE_BUFFER_POOL);
 
+static GstBuffer *
+gst_v4l2_codec_pool_create_empty_buffer (void)
+{
+  GstVideoMeta *vmeta;
+  GstBuffer *buffer = gst_buffer_new ();
+
+  vmeta = gst_buffer_add_video_meta (buffer, 0, GST_VIDEO_FORMAT_NV12, 1, 1);
+  GST_META_FLAG_SET (vmeta, GST_META_FLAG_POOLED);
+
+  return buffer;
+}
+
 static GstFlowReturn
 gst_v4l2_codec_pool_acquire_buffer (GstBufferPool * pool, GstBuffer ** buffer,
     GstBufferPoolAcquireParams * params)
 {
   GstV4l2CodecPool *self = GST_V4L2_CODEC_POOL (pool);
-  GstBuffer *buf = gst_atomic_queue_pop (self->queue);
+  GstBuffer *buf;
   GstVideoMeta *vmeta;
 
   /* A GstVideoInfo must be set before buffer can be acquired */
   g_return_val_if_fail (self->vinfo, GST_FLOW_ERROR);
 
+  buf = gst_atomic_queue_pop (self->queue);
   if (!buf)
-    return GST_FLOW_ERROR;
+    buf = gst_v4l2_codec_pool_create_empty_buffer ();
 
-  if (!gst_v4l2_codec_allocator_prepare_buffer (self->allocator, buf))
+  if (!gst_v4l2_codec_allocator_prepare_buffer (self->allocator, buf)) {
+    gst_atomic_queue_push (self->queue, buf);
     return GST_FLOW_ERROR;
+  }
 
   vmeta = gst_buffer_get_video_meta (buf);
   vmeta->format = GST_VIDEO_INFO_FORMAT (self->vinfo);
@@ -130,12 +145,7 @@ gst_v4l2_codec_pool_new (GstV4l2CodecAllocator * allocator,
 
   pool_size = gst_v4l2_codec_allocator_get_pool_size (allocator);
   for (gsize i = 0; i < pool_size; i++) {
-    GstVideoMeta *vmeta;
-    GstBuffer *buffer = gst_buffer_new ();
-
-    vmeta = gst_buffer_add_video_meta (buffer, 0, GST_VIDEO_FORMAT_NV12, 1, 1);
-    GST_META_FLAG_SET (vmeta, GST_META_FLAG_POOLED);
-
+    GstBuffer *buffer = gst_v4l2_codec_pool_create_empty_buffer ();
     gst_atomic_queue_push (pool->queue, buffer);
   }