sys/v4l2/v4l2src_calls.c (gst_v4l2_buffer_finalize) (gst_v4l2_buffer_class_init, gst_v4l2_buffer_get_type)

Original commit message from CVS:
2007-06-12  Andy Wingo  <wingo@pobox.com>

* sys/v4l2/v4l2src_calls.c (gst_v4l2_buffer_finalize)
(gst_v4l2_buffer_class_init, gst_v4l2_buffer_get_type)
(gst_v4l2_buffer_new): Behave more like ximagesink's buffers, with
finalization and resuscitation. No longer public.
(gst_v4l2_buffer_pool_finalize, gst_v4l2_buffer_pool_init)
(gst_v4l2_buffer_pool_class_init, gst_v4l2_buffer_pool_get_type)
(gst_v4l2_buffer_pool_new, gst_v4l2_buffer_pool_activate)
(gst_v4l2_buffer_pool_destroy): Make the pool follow common
miniobject semantics, and be threadsafe.
(gst_v4l2src_queue_frame): Remove this function, as we just call
the ioctls directly in the two places where we queue buffers.
(gst_v4l2src_grab_frame): Return a flowreturn and fill the buffer
directly.
(gst_v4l2src_capture_init): Use the new buffer_pool_new function
to allocate the pool, which also preallocates the GstBuffers.
(gst_v4l2src_capture_start): Call buffer_pool_activate instead of
queueing the frames directly.

* sys/v4l2/gstv4l2src.h (struct _GstV4l2BufferPool): Make this a
real MiniObject instead of rolling our own refcounting and
finalizing. Give it a lock.
(struct _GstV4l2Buffer): Remove one intermediary object, having
the buffers hold the struct v4l2_buffer directly.

* sys/v4l2/gstv4l2src.c (gst_v4l2src_set_caps): Pass the caps to
capture_init so that it can set them on the buffers that it will
create.
(gst_v4l2src_get_read): For better or for worse, include the
timestamping and offsetting code here; really we should be using
bufferalloc though.
(gst_v4l2src_get_mmap): Just make grab_frame return one of our
preallocated, mmap'd buffers.