text: /*
   * Copyright (c) 2017, Intel Corporation
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice,
   * this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   * this list of conditions and the following disclaimer in the documentation
   * and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   * THE POSSIBILITY OF SUCH DAMAGE.
   */
  #ifndef SOURCE_INTERFACE_H
  #define SOURCE_INTERFACE_H
  
  #include <glib-object.h>
  
  #include "sink-interface.h"
  
  G_BEGIN_DECLS
  
  #define TYPE_SOURCE                (source_get_type ())
  #define SOURCE(obj)                (G_TYPE_CHECK_INSTANCE_CAST ((obj),     TYPE_SOURCE, Source))
  #define IS_SOURCE(obj)             (G_TYPE_CHECK_INSTANCE_TYPE ((obj),     TYPE_SOURCE))
  #define SOURCE_GET_INTERFACE(inst) (G_TYPE_INSTANCE_GET_INTERFACE ((inst), TYPE_SOURCE, SourceInterface))
  
  typedef struct _Source              Source;
  typedef struct _SourceInterface     SourceInterface;
  
  /* types for function pointers defined by interface */
  typedef void        (*SourceAddSink)        (Source        *self,
                                               Sink          *sink);
  
  struct _SourceInterface {
      GTypeInterface         parent;
      SourceAddSink          add_sink;
  };
  
  GType      source_get_type         (void);
  void       source_add_sink         (Source         *self,
                                      Sink           *sink);
  
  G_END_DECLS
  #endif /* SOURCE_INTERFACE_H */
  