Add skeletal sound driver for JACK

This doesn't make any sound yet, but it creates the JACK client and connects
the requested ports if any.

configure.ac

@@ -265,6 +265,16 @@ if test x$have_pulse = xyes; then
 	LIBS="$LIBS -lpulse"
 fi
 
+dnl Search for JACK unless --without-jack or --with-jack=no is given; require it for --with-jack
+AC_ARG_WITH([jack], [AS_HELP_STRING([--without-jack], [Disable JACK sound driver])])
+AS_IF([test "x$with_jack" != "xno"], [
+       AC_SEARCH_LIBS([jack_client_open], [jack], [have_jack=yes], [
+		       AS_IF([test "x$with_jack" != x], [
+			      AC_MSG_ERROR([--with-jack was specified but JACK was not found])
+			     ])
+		       ])
+])
+
 AC_MSG_CHECKING(if cstdlib breaks llabs)
 AC_LANG_PUSH(C++)
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stdlib.h>
@@ -283,6 +293,7 @@ AC_DEFINE(__STDC_FORMAT_MACROS, 1, [Use PRId64 and similar])
 
 AM_CONDITIONAL(HAVE_ALSA, test x$alsa != xfalse )
 AM_CONDITIONAL(HAVE_GTK, test "$enable_gtk2" != "no" )
+AM_CONDITIONAL(HAVE_JACK, test x$have_jack = xyes)
 AM_CONDITIONAL(HAVE_OSS, test x$ac_cv_header_sys_soundcard_h = xyes )
 AM_CONDITIONAL(HAVE_PULSE, test x$have_pulse = xyes)
 AM_CONDITIONAL(USE_CRASH_HANDLER, test "$use_crash_handler" = "yes" )

src/Makefile.am

@@ -225,6 +225,10 @@ if HAVE_PULSE
 Sound += arch/Sound/RageSoundDriver_PulseAudio.cpp arch/Sound/RageSoundDriver_PulseAudio.h
 endif
 
+if HAVE_JACK
+Sound += arch/Sound/RageSoundDriver_JACK.cpp arch/Sound/RageSoundDriver_JACK.h
+endif
+
 if HAVE_OSS
 Sound += arch/Sound/RageSoundDriver_OSS.cpp arch/Sound/RageSoundDriver_OSS.h
 endif

src/arch/Sound/RageSoundDriver_JACK.cpp

@@ -0,0 +1,184 @@
+#include "global.h"
+#include "RageSoundDriver_JACK.h"
+#include "RageLog.h"
+#include "RageUtil.h"
+#include "PrefsManager.h"
+#include "ProductInfo.h"
+
+REGISTER_SOUND_DRIVER_CLASS( JACK );
+
+RageSoundDriver_JACK::RageSoundDriver_JACK() :
+	RageSoundDriver()
+{
+	client = NULL;
+	port_l = NULL;
+	port_r = NULL;
+}
+
+RageSoundDriver_JACK::~RageSoundDriver_JACK()
+{
+	// Shut down client
+	jack_client_close(client);
+}
+
+RString RageSoundDriver_JACK::Init()
+{
+	jack_status_t status;
+	RString error;
+
+	// Open JACK client and call it "StepMania" or whatever
+	client = jack_client_open(PRODUCT_FAMILY, JackNullOption, &status);
+	if (client == NULL)
+		return "Couldn't connect to JACK server";
+
+	LOG->Trace("JACK connected at %u Hz", jack_get_sample_rate(client));
+
+	// Set callback for processing audio
+	if (jack_set_process_callback(client, ProcessTrampoline, this))
+	{
+		error = "Couldn't set JACK process callback";
+		goto out_close;
+	}
+
+	// TODO Set a jack_on_shutdown callback as well?  Probably just stop
+	// caring about sound altogether if that happens.
+
+	// Create output ports
+	port_l = jack_port_register(client, "out_l", JACK_DEFAULT_AUDIO_TYPE,
+			JackPortIsOutput, 0);
+	if (port_l == NULL)
+	{
+		error = "Couldn't create JACK port out_l";
+		goto out_close;
+	}
+
+	port_r = jack_port_register(client, "out_r", JACK_DEFAULT_AUDIO_TYPE,
+			JackPortIsOutput, 0);
+	if (port_r == NULL)
+	{
+		error = "Couldn't create JACK port out_r";
+		goto out_unreg_l;
+	}
+
+	// Go!
+	if (jack_activate(client))
+	{
+		error = "Couldn't activate JACK client";
+		goto out_unreg_r;
+	}
+
+	// Connect to playback port.  This currently requires that you specify
+	// the client using the SoundDevice preference.  The alternative is to
+	// connect automatically to something like `playback' if none is
+	// specified, which is not friendly JACK behavior.
+	error = ConnectPorts();
+	if (!error.empty())
+		goto out_deactivate;
+
+	// Success!
+	return RString();
+
+
+	// Not success!
+out_deactivate:
+	jack_deactivate(client);
+out_unreg_r:
+	jack_port_unregister(client, port_r);
+out_unreg_l:
+	jack_port_unregister(client, port_l);
+out_close:
+	jack_client_close(client);
+	return error;
+}
+
+RString RageSoundDriver_JACK::ConnectPorts()
+{
+	vector<RString> portNames;
+	split(PREFSMAN->m_iSoundDevice.Get(), ",", portNames, true);
+
+	switch (portNames.size())
+	{
+	case 0:
+		// No ports specified
+		return RString();
+	case 1:
+		// HACK: Pointing both channels at one port is probably the
+		// wrong way to mix to mono.  For now, it works.
+		portNames.push_back(portNames[0]);
+		break;
+	case 2:
+		break;
+	default:
+		LOG->Warn("More than two JACK ports specified; using the first two only.");
+		break;
+	}
+
+	ASSERT(portNames.size() >= 2);
+
+	// Use jack_port_by_name to ensure ports exist, then jack_port_name to
+	// use their canonical name.  (I'm not sure if that second step is
+	// necessary, I've seen something about "aliases" in the docs.)
+	jack_port_t *port_out = jack_port_by_name(client, portNames[0]);
+	if (port_out == NULL || jack_connect(client, jack_port_name(port_l), jack_port_name(port_out)))
+		return "Couldn't connect left JACK port";
+
+	port_out = jack_port_by_name(client, portNames[1]);
+	if (port_out == NULL || jack_connect(client, jack_port_name(port_r), jack_port_name(port_out)))
+		return "Couldn't connect right JACK port";
+
+	return RString();
+}
+
+int64_t RageSoundDriver_JACK::GetPosition() const
+{
+	return jack_frame_time(client);
+}
+
+int RageSoundDriver_JACK::GetSampleRate() const
+{
+	return jack_get_sample_rate(client);
+}
+
+int RageSoundDriver_JACK::ProcessCallback(jack_nframes_t nframes)
+{
+	jack_default_audio_sample_t *out_l =
+		(jack_default_audio_sample_t *) jack_port_get_buffer(port_l, nframes);
+	jack_default_audio_sample_t *out_r =
+		(jack_default_audio_sample_t *) jack_port_get_buffer(port_r, nframes);
+
+	memset(out_l, 0, nframes * sizeof(jack_default_audio_sample_t));
+	memset(out_r, 0, nframes * sizeof(jack_default_audio_sample_t));
+
+	return 0;
+}
+
+// Static callback trampoline
+int RageSoundDriver_JACK::ProcessTrampoline(jack_nframes_t nframes, void *arg)
+{
+	return ((RageSoundDriver_JACK *) arg)->ProcessCallback(nframes);
+}
+
+/*
+ * (c) 2013 Devin J. Pohly
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, and/or sell copies of the Software, and to permit persons to
+ * whom the Software is furnished to do so, provided that the above
+ * copyright notice(s) and this permission notice appear in all copies of
+ * the Software and that both the above copyright notice(s) and this
+ * permission notice appear in supporting documentation.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF
+ * THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
+ * INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
+ * OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */

src/arch/Sound/RageSoundDriver_JACK.h

@@ -0,0 +1,58 @@
+#ifndef RAGE_SOUND_JACK
+#define RAGE_SOUND_JACK
+
+#include "RageSoundDriver.h"
+#include <jack/jack.h>
+
+#define USE_RAGE_SOUND_JACK
+
+class RageSoundDriver_JACK: public RageSoundDriver
+{
+public:
+	RageSoundDriver_JACK();
+	~RageSoundDriver_JACK();
+
+	RString Init();
+
+	int GetSampleRate() const;
+	int64_t GetPosition() const;
+
+private:
+	jack_client_t *client;
+	jack_port_t *port_l;
+	jack_port_t *port_r;
+
+	// Helper for Init()
+	RString ConnectPorts();
+
+	// JACK callbacks and trampolines
+	int ProcessCallback(jack_nframes_t nframes);
+	static int ProcessTrampoline(jack_nframes_t nframes, void *arg);
+};
+
+#endif
+
+/*
+ * (c) 2013 Devin J. Pohly
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, and/or sell copies of the Software, and to permit persons to
+ * whom the Software is furnished to do so, provided that the above
+ * copyright notice(s) and this permission notice appear in all copies of
+ * the Software and that both the above copyright notice(s) and this
+ * permission notice appear in supporting documentation.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF
+ * THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
+ * INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
+ * OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */

src/arch/arch.cpp

@@ -264,6 +264,9 @@ RageSoundDriver *MakeRageSoundDriver( const RString &drivers )
 #ifdef USE_RAGE_SOUND_DSOUND_SOFTWARE
 		if( !DriversToTry[i].CompareNoCase("DirectSound-sw") )	ret = new RageSound_DSound_Software;
 #endif
+#ifdef USE_RAGE_SOUND_JACK
+		if( !DriversToTry[i].CompareNoCase("JACK") )		ret = new RageSound_JACK;
+#endif
 #ifdef USE_RAGE_SOUND_NULL
 		if( !DriversToTry[i].CompareNoCase("Null") )		ret = new RageSound_Null;
 #endif