Re: gstmm add element to pipeline test

[José Alburquerque <jaalburquerque cox net>]

Murray Cumming wrote:
> So, I have committed bus-message-02.diff. Should I add one of the .cc
> files (which one?) as an example?
>
> Thanks. And sorry that you don't yet have svn write access - I have no
> control over that svn repository.
>
>   

Thanks.  Yes, I suppose that the slot version might be good since it is 
how it is done in C by default.  I really appreciate you committing  
these changes for me.  I'm attaching a new version of the slot example 
(which parses the message so the error output is more explicit) and 
would you also add this small patch which consolidates the 
Gst::Bus::add_watch() methods into one (if you think it's alright)?  It 
seems better to have just one "do-all" method, unless you think 
otherwise.  Thanks.

-Jose

#include <iostream>
#include <gstmm.h>

using namespace Glib;
using namespace Gst;
using namespace std;

bool process_bus_message(const RefPtr<Bus>& bus, const RefPtr<Message>& message,
RefPtr<MainLoop> mainLoop)
{
  RefPtr<MessageError> msgError;
  Error err;
  std::string debug;

  switch (message->get_type()) {
    case MESSAGE_EOS:
      cout << "End of stream" << endl;
      mainLoop->quit();
      return false;
    case MESSAGE_ERROR:
      msgError = RefPtr<MessageError>::cast_static(message);
      if (msgError) {
        msgError->parse(err, debug);
        cerr << "Error: " << err.what() << endl;
      }
      else
        cerr << "Error." << endl;
      mainLoop->quit();
      return false;
    default:
      break;
  }
  return true;
}

void parser_pad_added(const RefPtr<Pad>& newPad, RefPtr<Element> decoder)
{
  cout << "Dynamic pad created, linking parser/decoder." << endl;
  RefPtr<Pad> sinkPad = decoder->get_pad("sink");
  newPad->link(sinkPad);
}

int main(int argc, char* argv[]) {
  if (argc != 2) {
    cout << "Usage: " << argv[0] << " <Ogg/Vorbis filename>" << endl;
    return -1;
  }

  Gst::init(argc, argv);
  RefPtr<MainLoop> mainLoop = Glib::MainLoop::create();

  /* create elements */
  RefPtr<Pipeline> pipeline = Gst::Pipeline::create("audio-player");
  RefPtr<Element> source = Gst::Element::create("filesrc", "file-source");
  RefPtr<Element> parser = Gst::Element::create("oggdemux", "ogg-parser");
  RefPtr<Element> decoder = Gst::Element::create("vorbisdec", "vorbis-decoder");
  RefPtr<Element> conv = Gst::Element::create("audioconvert", "converter");
  RefPtr<Element> sink = Gst::Element::create("alsasink", "alsa-output");

  if (!pipeline || !source || !parser || !decoder || !conv || !sink) {
    cerr << "One element could not be created." << endl;
    return -1;
  }

  /* set filename property on the file source. Also add a message
   * handler. */
  source->set_property("location", (string) argv[1]);

  RefPtr<Bus> bus = pipeline->get_bus();
  Bus::SlotWatch slot(sigc::bind< RefPtr<MainLoop> >( sigc::ptr_fun(&process_bus_message), mainLoop) );
  bus->add_watch(slot);

  /* put all elements in a bin */
  pipeline->add(source)->add(parser)->add(decoder)->add(conv)->add(sink);

  /* link together - note that we cannot link the parser and
   * decoder yet, becuse the parser uses dynamic pads. For that,
   * we set a pad-added signal handler. */
  source->link(parser);
  decoder->link(conv)->link(sink);

  parser->signal_pad_added().connect(sigc::bind< RefPtr<Element> >(
    sigc::ptr_fun(&parser_pad_added), decoder) );

  /* Now set to playing and iterate. */
  cout << "Setting to PLAYING." << endl;
  pipeline->set_state(STATE_PLAYING);
  cout << "Running." << endl;
  mainLoop->run();

  /* clean up nicely */
  cout << "Returned, stopping playback." << endl;
  pipeline->set_state(STATE_NULL);

  return 0;
}

Index: gst/src/bus.hg
===================================================================
--- gst/src/bus.hg	(revision 96)
+++ gst/src/bus.hg	(working copy)
@@ -41,9 +41,9 @@
   _WRAP_METHOD(void disable_sync_message_emission(), gst_bus_disable_sync_message_emission)
   _WRAP_METHOD(void enable_sync_message_emission(), gst_bus_enable_sync_message_emission)
 
-  _WRAP_METHOD(void add_signal_watch(), gst_bus_add_signal_watch)
-  _WRAP_METHOD(void add_signal_watch_full(int priority), gst_bus_add_signal_watch_full)
+  _WRAP_METHOD(void add_signal_watch(int priority = G_PRIORITY_DEFAULT), gst_bus_add_signal_watch_full)
   _WRAP_METHOD(void remove_signal_watch(), gst_bus_remove_signal_watch)
+  _IGNORE(gst_bus_add_signal_watch)
 
 #m4 _CONVERSION(`GstMessage*',`const Glib::RefPtr<Message>&', `Glib::wrap($3, true)')
   _WRAP_SIGNAL(void message(const Glib::RefPtr<Message>& message), "message")