added backend midi code

backends/midi/seq.cpp

@@ -0,0 +1,219 @@
+/* Residual - A 3D game interpreter
+ *
+ * Residual is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the AUTHORS
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * $URL$
+ * $Id$
+ */
+
+/*
+ * Raw output support by Michael Pearce
+ * Alsa support by Nicolas Noble <nicolas@nobis-crew.org> copied from
+ *    both the QuickTime support and (vkeybd http://www.alsa-project.org/~iwai/alsa.html)
+ */
+
+#if defined(UNIX) && !defined(__BEOS__) && !defined(__MAEMO__) && !defined(__MINT__)
+
+#include "common/util.h"
+#include "sound/musicplugin.h"
+#include "sound/mpu401.h"
+
+#include <fcntl.h>
+#include <unistd.h>
+
+////////////////////////////////////////
+//
+// Unix dev/sequencer driver
+//
+////////////////////////////////////////
+
+#define SEQ_MIDIPUTC 5
+
+class MidiDriver_SEQ : public MidiDriver_MPU401 {
+public:
+	MidiDriver_SEQ();
+	int open();
+	void close();
+	void send(uint32 b);
+	void sysEx(const byte *msg, uint16 length);
+
+private:
+	bool _isOpen;
+	int device, _device_num;
+};
+
+MidiDriver_SEQ::MidiDriver_SEQ() {
+	_isOpen = false;
+	device = 0;
+	_device_num = 0;
+}
+
+int MidiDriver_SEQ::open() {
+	char *device_name;
+	char dev_seq[] = "/dev/sequencer";
+
+	if (_isOpen)
+		return MERR_ALREADY_OPEN;
+	_isOpen = true;
+	device = 0;
+
+	device_name = getenv("SCUMMVM_MIDI");
+
+	if (device_name == NULL) {
+		warning("SCUMMVM_MIDI environment variable not set, using /dev/sequencer");
+		device_name = dev_seq;
+	}
+
+	device = (::open((device_name), O_RDWR, 0));
+
+	if ((device_name == NULL) || (device < 0)) {
+		if (device_name == NULL)
+			warning("Opening /dev/null (no music will be heard) ");
+		else
+			warning("Cannot open rawmidi device %s - using /dev/null (no music will be heard) ",
+							device_name);
+		device = (::open(("/dev/null"), O_RDWR, 0));
+		if (device < 0)
+			error("Cannot open /dev/null to dump midi output");
+	}
+
+	if (getenv("SCUMMVM_MIDIPORT"))
+		_device_num = atoi(getenv("SCUMMVM_MIDIPORT"));
+	return 0;
+}
+
+void MidiDriver_SEQ::close() {
+	MidiDriver_MPU401::close();
+	::close(device);
+	_isOpen = false;
+}
+
+void MidiDriver_SEQ::send(uint32 b) {
+	unsigned char buf[256];
+	int position = 0;
+
+	switch (b & 0xF0) {
+	case 0x80:
+	case 0x90:
+	case 0xA0:
+	case 0xB0:
+	case 0xE0:
+		buf[position++] = SEQ_MIDIPUTC;
+		buf[position++] = (unsigned char)b;
+		buf[position++] = _device_num;
+		buf[position++] = 0;
+		buf[position++] = SEQ_MIDIPUTC;
+		buf[position++] = (unsigned char)((b >> 8) & 0x7F);
+		buf[position++] = _device_num;
+		buf[position++] = 0;
+		buf[position++] = SEQ_MIDIPUTC;
+		buf[position++] = (unsigned char)((b >> 16) & 0x7F);
+		buf[position++] = _device_num;
+		buf[position++] = 0;
+		break;
+	case 0xC0:
+	case 0xD0:
+		buf[position++] = SEQ_MIDIPUTC;
+		buf[position++] = (unsigned char)b;
+		buf[position++] = _device_num;
+		buf[position++] = 0;
+		buf[position++] = SEQ_MIDIPUTC;
+		buf[position++] = (unsigned char)((b >> 8) & 0x7F);
+		buf[position++] = _device_num;
+		buf[position++] = 0;
+		break;
+	default:
+		warning("MidiDriver_SEQ::send: unknown : %08x", (int)b);
+		break;
+	}
+	(void)write(device, buf, position);
+}
+
+void MidiDriver_SEQ::sysEx (const byte *msg, uint16 length) {
+	unsigned char buf [266*4];
+	int position = 0;
+	const byte *chr = msg;
+
+	assert(length + 2 <= 266);
+
+	buf[position++] = SEQ_MIDIPUTC;
+	buf[position++] = 0xF0;
+	buf[position++] = _device_num;
+	buf[position++] = 0;
+	for (; length; --length, ++chr) {
+		buf[position++] = SEQ_MIDIPUTC;
+		buf[position++] = (unsigned char) *chr & 0x7F;
+		buf[position++] = _device_num;
+		buf[position++] = 0;
+	}
+	buf[position++] = SEQ_MIDIPUTC;
+	buf[position++] = 0xF7;
+	buf[position++] = _device_num;
+	buf[position++] = 0;
+
+	(void)write(device, buf, position);
+}
+
+
+// Plugin interface
+
+class SeqMusicPlugin : public MusicPluginObject {
+public:
+	const char *getName() const {
+		return "SEQ";
+	}
+
+	const char *getId() const {
+		return "seq";
+	}
+
+	MusicDevices getDevices() const;
+	Common::Error createInstance(MidiDriver **mididriver) const;
+};
+
+MusicDevices SeqMusicPlugin::getDevices() const {
+	MusicDevices devices;
+	// TODO: Return a different music type depending on the configuration
+	// TODO: List the available devices
+	devices.push_back(MusicDevice(this, "", MT_GM));
+	return devices;
+}
+
+Common::Error SeqMusicPlugin::createInstance(MidiDriver **mididriver) const {
+	*mididriver = new MidiDriver_SEQ();
+
+	return Common::kNoError;
+}
+
+MidiDriver *MidiDriver_SEQ_create() {
+	MidiDriver *mididriver;
+
+	SeqMusicPlugin p;
+	p.createInstance(&mididriver);
+
+	return mididriver;
+}
+
+//#if PLUGIN_ENABLED_DYNAMIC(SEQ)
+	//REGISTER_PLUGIN_DYNAMIC(SEQ, PLUGIN_TYPE_MUSIC, SeqMusicPlugin);
+//#else
+	REGISTER_PLUGIN_STATIC(SEQ, PLUGIN_TYPE_MUSIC, SeqMusicPlugin);
+//#endif
+
+#endif