GstBufferStraw

GstBufferStraw — Buffer interception code for GStreamer unit tests

Synopsis


#include <gst/check/gstbufferstraw.h>

void                gst_buffer_straw_start_pipeline     (GstElement *bin,
                                                         GstPad *pad);
GstBuffer*          gst_buffer_straw_get_buffer         (GstElement *bin,
                                                         GstPad *pad);
void                gst_buffer_straw_stop_pipeline      (GstElement *bin,
                                                         GstPad *pad);

Description

These macros and functions are for internal use of the unit tests found inside the 'check' directories of various GStreamer packages.

Details

gst_buffer_straw_start_pipeline ()

void                gst_buffer_straw_start_pipeline     (GstElement *bin,
                                                         GstPad *pad);

Sets up a pipeline for buffer sucking. This will allow you to call gst_buffer_straw_get_buffer() to access buffers as they pass over pad.

This function is normally used in unit tests that want to verify that a particular element is outputting correct buffers. For example, you would make a pipeline via gst_parse_launch(), pull out the pad you want to monitor, then call gst_buffer_straw_get_buffer() to get the buffers that pass through pad. The pipeline will block until you have sucked off the buffers.

This function will set the state of bin to PLAYING; to clean up, be sure to call gst_buffer_straw_stop_pipeline().

Note that you may not start two buffer straws at the same time. This function is intended for unit tests, not general API use. In fact it calls fail_if from libcheck, so you cannot use it outside unit tests.

bin : the pipeline to run
pad : a pad on an element in bin

gst_buffer_straw_get_buffer ()

GstBuffer*          gst_buffer_straw_get_buffer         (GstElement *bin,
                                                         GstPad *pad);

Get one buffer from pad. Implemented via buffer probes. This function will block until the pipeline passes a buffer over pad, so for robust behavior in unit tests, you need to use check's timeout to fail out in the case that a buffer never arrives.

You must have previously called gst_buffer_straw_start_pipeline() on pipeline and pad.

bin : the pipeline previously started via gst_buffer_straw_start_pipeline()
pad : the pad previously passed to gst_buffer_straw_start_pipeline()
Returns : the captured GstBuffer.

gst_buffer_straw_stop_pipeline ()

void                gst_buffer_straw_stop_pipeline      (GstElement *bin,
                                                         GstPad *pad);

Set bin to GST_STATE_NULL and release resource allocated in gst_buffer_straw_start_pipeline().

You must have previously called gst_buffer_straw_start_pipeline() on pipeline and pad.

bin : the pipeline previously started via gst_buffer_straw_start_pipeline()
pad : the pad previously passed to gst_buffer_straw_start_pipeline()