Moved all of the sound iterator code in its own directory, and added a slight hack to the SoundCommandParser constructor

svn-id: r46430

1 files changed, 1707 insertions, 0 deletions

diff --git a/engines/sci/sfx/iterator/iterator.cpp b/engines/sci/sfx/iterator/iterator.cpp
new file mode 100644
index 0000000000..924e1de0bc
--- /dev/null
+++ b/engines/sci/sfx/iterator/iterator.cpp
@@ -0,0 +1,1707 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * 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.
+ *
+ * $URL$
+ * $Id$
+ *
+ */
+
+/* Song iterators */
+
+#include "common/util.h"
+
+#include "sci/sci.h"
+#ifdef USE_OLD_MUSIC_FUNCTIONS
+
+#include "sci/sfx/iterator/iterator_internal.h"
+#include "sci/engine/state.h"	// for sfx_player_tell_synth :/
+#include "sci/sfx/iterator/core.h"	// for sfx_player_tell_synth
+
+#include "sound/audiostream.h"
+#include "sound/mixer.h"
+
+namespace Sci {
+
+
+static const int MIDI_cmdlen[16] = {0, 0, 0, 0, 0, 0, 0, 0,
+                                    2, 2, 2, 2, 1, 1, 2, 0
+                                   };
+
+/*#define DEBUG_DECODING*/
+/*#define DEBUG_VERBOSE*/
+
+/** Find first set bit in bits and return its index. Returns 0 if bits is 0. */
+static int sci_ffs(int bits) {
+	if (!bits)
+		return 0;
+
+	int retval = 1;
+
+	while (!(bits & 1)) {
+		retval++;
+		bits >>= 1;
+	}
+
+	return retval;
+}
+
+static void print_tabs_id(int nr, songit_id_t id) {
+	while (nr-- > 0)
+		fprintf(stderr, "\t");
+
+	fprintf(stderr, "[%08lx] ", id);
+}
+
+BaseSongIterator::BaseSongIterator(byte *data, uint size, songit_id_t id)
+	: _data(data, size) {
+	ID = id;
+}
+
+/************************************/
+/*-- SCI0 iterator implementation --*/
+/************************************/
+
+#define SCI0_MIDI_OFFSET 33
+#define SCI0_END_OF_SONG 0xfc /* proprietary MIDI command */
+
+#define SCI0_PCM_SAMPLE_RATE_OFFSET 0x0e
+#define SCI0_PCM_SIZE_OFFSET 0x20
+#define SCI0_PCM_DATA_OFFSET 0x2c
+
+#define CHECK_FOR_END_ABSOLUTE(offset) \
+	if (offset > _data.size()) { \
+		warning("Reached end of song without terminator (%x/%x) at %d", offset, _data.size(), __LINE__); \
+		return SI_FINISHED; \
+	}
+
+#define CHECK_FOR_END(offset_augment) \
+	if ((channel->offset + (offset_augment)) > channel->end) { \
+		channel->state = SI_STATE_FINISHED; \
+		warning("Reached end of track %d without terminator (%x+%x/%x) at %d", channel->id, channel->offset, offset_augment, channel->end, __LINE__); \
+		return SI_FINISHED; \
+	}
+
+
+static int _parse_ticks(byte *data, int *offset_p, int size) {
+	int ticks = 0;
+	int tempticks;
+	int offset = 0;
+
+	do {
+		tempticks = data[offset++];
+		ticks += (tempticks == SCI_MIDI_TIME_EXPANSION_PREFIX) ?
+		         SCI_MIDI_TIME_EXPANSION_LENGTH : tempticks;
+	} while (tempticks == SCI_MIDI_TIME_EXPANSION_PREFIX
+	         && offset < size);
+
+	if (offset_p)
+		*offset_p = offset;
+
+	return ticks;
+}
+
+
+static int _sci0_get_pcm_data(Sci0SongIterator *self, int *rate, int *xoffset, uint *xsize);
+
+
+#define PARSE_FLAG_LOOPS_UNLIMITED (1 << 0) /* Unlimited # of loops? */
+#define PARSE_FLAG_PARAMETRIC_CUE (1 << 1) /* Assume that cues take an additional "cue value" argument */
+/* This implements a difference between SCI0 and SCI1 cues. */
+
+void SongIteratorChannel::init(int id_, int offset_, int end_) {
+	playmask = PLAYMASK_NONE; /* Disable all channels */
+	id = id_;
+	state = SI_STATE_DELTA_TIME;
+	loop_timepos = 0;
+	total_timepos = 0;
+	timepos_increment = 0;
+	delay = 0; /* Only used for more than one channel */
+	last_cmd = 0xfe;
+
+	offset = loop_offset = initial_offset = offset_;
+	end = end_;
+}
+
+void SongIteratorChannel::resetSynthChannels() {
+	byte buf[5];
+
+	// FIXME: Evil hack
+	SfxState &sound = ((SciEngine*)g_engine)->getEngineState()->_sound;
+
+	for (int i = 0; i < MIDI_CHANNELS; i++) {
+		if (playmask & (1 << i)) {
+			buf[0] = 0xe0 | i; /* Pitch bend */
+			buf[1] = 0x80; /* Wheel center */
+			buf[2] = 0x40;
+			sound.sfx_player_tell_synth(3, buf);
+
+			buf[0] = 0xb0 | i; // Set control
+			buf[1] = 0x40; // Hold pedal
+			buf[2] = 0x00; // Off
+			sound.sfx_player_tell_synth(3, buf);
+			/* TODO: Reset other controls? */
+		}
+	}
+}
+
+int BaseSongIterator::parseMidiCommand(byte *buf, int *result, SongIteratorChannel *channel, int flags) {
+	byte cmd;
+	int paramsleft;
+	int midi_op;
+	int midi_channel;
+
+	channel->state = SI_STATE_DELTA_TIME;
+
+	cmd = _data[channel->offset++];
+
+	if (!(cmd & 0x80)) {
+		/* 'Running status' mode */
+		channel->offset--;
+		cmd = channel->last_cmd;
+	}
+
+	if (cmd == 0xfe) {
+		warning("song iterator subsystem: Corrupted sound resource detected.");
+		return SI_FINISHED;
+	}
+
+	midi_op = cmd >> 4;
+	midi_channel = cmd & 0xf;
+	paramsleft = MIDI_cmdlen[midi_op];
+
+#if 0
+	if (1) {
+		fprintf(stderr, "[IT]: off=%x, cmd=%02x, takes %d args ",
+		        channel->offset - 1, cmd, paramsleft);
+		fprintf(stderr, "[%02x %02x <%02x> %02x %02x %02x]\n",
+		        _data[channel->offset-3],
+		        _data[channel->offset-2],
+		        _data[channel->offset-1],
+		        _data[channel->offset],
+		        _data[channel->offset+1],
+		        _data[channel->offset+2]);
+	}
+#endif
+
+	buf[0] = cmd;
+
+
+	CHECK_FOR_END(paramsleft);
+	memcpy(buf + 1, _data.begin() + channel->offset, paramsleft);
+	*result = 1 + paramsleft;
+
+	channel->offset += paramsleft;
+
+	channel->last_cmd = cmd;
+
+	/* Are we supposed to play this channel? */
+	if (
+	    /* First, exclude "global" properties-- such as cues-- from consideration */
+	    (midi_op < 0xf
+	     && !(cmd == SCI_MIDI_SET_SIGNAL)
+	     && !(SCI_MIDI_CONTROLLER(cmd)
+	          && buf[1] == SCI_MIDI_CUMULATIVE_CUE))
+
+	    /* Next, check if the channel is allowed */
+	    && (!((1 << midi_channel) & channel->playmask)))
+		return  /* Execute next command */
+		    nextCommand(buf, result);
+
+
+	if (cmd == SCI_MIDI_EOT) {
+		/* End of track? */
+		channel->resetSynthChannels();
+		if (_loops > 1) {
+			/* If allowed, decrement the number of loops */
+			if (!(flags & PARSE_FLAG_LOOPS_UNLIMITED))
+				*result = --_loops;
+
+#ifdef DEBUG_DECODING
+			fprintf(stderr, "%s L%d: (%p):%d Looping ", __FILE__, __LINE__, this, channel->id);
+			if (flags & PARSE_FLAG_LOOPS_UNLIMITED)
+				fprintf(stderr, "(indef.)");
+			else
+				fprintf(stderr, "(%d)", _loops);
+			fprintf(stderr, " %x -> %x\n",
+			        channel->offset, channel->loop_offset);
+#endif
+			channel->offset = channel->loop_offset;
+			channel->state = SI_STATE_DELTA_TIME;
+			channel->total_timepos = channel->loop_timepos;
+			channel->last_cmd = 0xfe;
+			debugC(2, kDebugLevelSound, "Looping song iterator %08lx.\n", ID);
+			return SI_LOOP;
+		} else {
+			channel->state = SI_STATE_FINISHED;
+			return SI_FINISHED;
+		}
+
+	} else if (cmd == SCI_MIDI_SET_SIGNAL) {
+		if (buf[1] == SCI_MIDI_SET_SIGNAL_LOOP) {
+			channel->loop_offset = channel->offset;
+			channel->loop_timepos = channel->total_timepos;
+
+			return /* Execute next command */
+			    nextCommand(buf, result);
+		} else {
+			/* Used to be conditional <= 127 */
+			*result = buf[1]; /* Absolute cue */
+			return SI_ABSOLUTE_CUE;
+		}
+	} else if (SCI_MIDI_CONTROLLER(cmd)) {
+		switch (buf[1]) {
+
+		case SCI_MIDI_CUMULATIVE_CUE:
+			if (flags & PARSE_FLAG_PARAMETRIC_CUE)
+				_ccc += buf[2];
+			else { /* No parameter to CC */
+				_ccc++;
+				/*				channel->offset--; */
+			}
+			*result = _ccc;
+			return SI_RELATIVE_CUE;
+
+		case SCI_MIDI_RESET_ON_SUSPEND:
+			_resetflag = buf[2];
+			break;
+
+		case SCI_MIDI_SET_POLYPHONY:
+			_polyphony[midi_channel] = buf[2];
+
+#if 0
+			{
+				Sci1SongIterator *self1 = (Sci1SongIterator *)this;
+				int i;
+				int voices = 0;
+				for (i = 0; i < self1->_numChannels; i++) {
+					voices += _polyphony[i];
+				}
+
+				printf("SET_POLYPHONY(%d, %d) for a total of %d voices\n", midi_channel, buf[2], voices);
+				printf("[iterator] DEBUG: Polyphony = [ ");
+				for (i = 0; i < self1->_numChannels; i++)
+					printf("%d ", _polyphony[i]);
+				printf("]\n");
+				printf("[iterator] DEBUG: Importance = [ ");
+				printf("]\n");
+			}
+#endif
+			break;
+
+		case SCI_MIDI_SET_REVERB:
+			break;
+
+		case SCI_MIDI_CHANNEL_MUTE:
+			warning("CHANNEL_MUTE(%d, %d)", midi_channel, buf[2]);
+			break;
+
+		case SCI_MIDI_HOLD: {
+			// Safe cast: This controller is only used in SCI1
+			Sci1SongIterator *self1 = (Sci1SongIterator *)this;
+
+			if (buf[2] == self1->_hold) {
+				channel->offset = channel->initial_offset;
+				channel->state = SI_STATE_COMMAND;
+				channel->total_timepos = 0;
+
+				self1->_numLoopedChannels = self1->_numActiveChannels - 1;
+
+				// FIXME:
+				// This implementation of hold breaks getting out of the
+				// limo when visiting the airport near the start of LSL5.
+				// It seems like all channels should be reset here somehow,
+				// but not sure how.
+				// Forcing all channel offsets to 0 seems to fix the hang,
+				// but somehow slows the exit sequence down to take 20 seconds
+				// instead of about 3.
+
+				return SI_LOOP;
+			}
+
+			break;
+		}
+		case 0x04: /* UNKNOWN NYI (happens in LSL2 gameshow) */
+		case 0x46: /* UNKNOWN NYI (happens in LSL3 binoculars) */
+		case 0x61: /* UNKNOWN NYI (special for adlib? Iceman) */
+		case 0x73: /* UNKNOWN NYI (happens in Hoyle) */
+		case 0xd1: /* UNKNOWN NYI (happens in KQ4 when riding the unicorn) */
+			return /* Execute next command */
+			    nextCommand(buf, result);
+
+		case 0x01: /* modulation */
+		case 0x07: /* volume */
+		case 0x0a: /* panpot */
+		case 0x0b: /* expression */
+		case 0x40: /* hold */
+		case 0x79: /* reset all */
+			/* No special treatment neccessary */
+			break;
+
+		}
+		return 0;
+
+	} else {
+#if 0
+		/* Perform remapping, if neccessary */
+		if (cmd != SCI_MIDI_SET_SIGNAL
+				&& cmd < 0xf0) { /* Not a generic command */
+			int chan = cmd & 0xf;
+			int op = cmd & 0xf0;
+
+			chan = channel_remap[chan];
+			buf[0] = chan | op;
+		}
+#endif
+
+		/* Process as normal MIDI operation */
+		return 0;
+	}
+}
+
+int BaseSongIterator::processMidi(byte *buf, int *result,
+	SongIteratorChannel *channel, int flags) {
+	CHECK_FOR_END(0);
+
+	switch (channel->state) {
+
+	case SI_STATE_PCM: {
+		if (_data[channel->offset] == 0
+		        && _data[channel->offset + 1] == SCI_MIDI_EOT)
+			/* Fake one extra tick to trick the interpreter into not killing the song iterator right away */
+			channel->state = SI_STATE_PCM_MAGIC_DELTA;
+		else
+			channel->state = SI_STATE_DELTA_TIME;
+		return SI_PCM;
+	}
+
+	case SI_STATE_PCM_MAGIC_DELTA: {
+		int rate;
+		int offset;
+		uint size;
+		int delay;
+		if (_sci0_get_pcm_data((Sci0SongIterator *)this, &rate, &offset, &size))
+			return SI_FINISHED; /* 'tis broken */
+		channel->state = SI_STATE_FINISHED;
+		delay = (size * 50 + rate - 1) / rate; /* number of ticks to completion*/
+
+		debugC(2, kDebugLevelSound, "delaying %d ticks\n", delay);
+		return delay;
+	}
+
+	case SI_STATE_UNINITIALISED:
+		warning("Attempt to read command from uninitialized iterator");
+		init();
+		return nextCommand(buf, result);
+
+	case SI_STATE_FINISHED:
+		return SI_FINISHED;
+
+	case SI_STATE_DELTA_TIME: {
+		int offset;
+		int ticks = _parse_ticks(_data.begin() + channel->offset,
+		                         &offset,
+		                         _data.size() - channel->offset);
+
+		channel->offset += offset;
+		channel->delay += ticks;
+		channel->timepos_increment = ticks;
+
+		CHECK_FOR_END(0);
+
+		channel->state = SI_STATE_COMMAND;
+
+		if (ticks)
+			return ticks;
+	}
+
+	/* continute otherwise... */
+
+	case SI_STATE_COMMAND: {
+		int retval;
+		channel->total_timepos += channel->timepos_increment;
+		channel->timepos_increment = 0;
+
+		retval = parseMidiCommand(buf, result, channel, flags);
+
+		if (retval == SI_FINISHED) {
+			if (_numActiveChannels)
+				--(_numActiveChannels);
+#ifdef DEBUG_DECODING
+			fprintf(stderr, "%s L%d: (%p):%d Finished channel, %d channels left\n",
+			        __FILE__, __LINE__, this, channel->id,
+			        _numActiveChannels);
+#endif
+			/* If we still have channels left... */
+			if (_numActiveChannels) {
+				return nextCommand(buf, result);
+			}
+
+			/* Otherwise, we have reached the end */
+			_loops = 0;
+		}
+
+		return retval;
+	}
+
+	default:
+		error("Invalid iterator state %d", channel->state);
+		return SI_FINISHED;
+	}
+}
+
+int Sci0SongIterator::nextCommand(byte *buf, int *result) {
+	return processMidi(buf, result, &_channel, PARSE_FLAG_PARAMETRIC_CUE);
+}
+
+static int _sci0_header_magic_p(byte *data, int offset, int size) {
+	if (offset + 0x10 > size)
+		return 0;
+	return (data[offset] == 0x1a)
+	    && (data[offset + 1] == 0x00)
+	    && (data[offset + 2] == 0x01)
+	    && (data[offset + 3] == 0x00);
+}
+
+
+static int _sci0_get_pcm_data(Sci0SongIterator *self,
+	int *rate, int *xoffset, uint *xsize) {
+	int tries = 2;
+	bool found_it = false;
+	byte *pcm_data;
+	int size;
+	uint offset = SCI0_MIDI_OFFSET;
+
+	if (self->_data[0] != 2)
+		return 1;
+	/* No such luck */
+
+	while ((tries--) && (offset < self->_data.size()) && (!found_it)) {
+		// Search through the garbage manually
+		// FIXME: Replace offset by an iterator
+		Common::Array<byte>::iterator iter = Common::find(self->_data.begin() + offset, self->_data.end(), SCI0_END_OF_SONG);
+
+		if (iter == self->_data.end()) {
+			warning("Playing unterminated song");
+			return 1;
+		}
+
+		// add one to move it past the END_OF_SONG marker
+		iter++;
+		offset = iter - self->_data.begin();	// FIXME
+
+
+		if (_sci0_header_magic_p(self->_data.begin(), offset, self->_data.size()))
+			found_it = true;
+	}
+
+	if (!found_it) {
+		warning("Song indicates presence of PCM, but"
+		        " none found (finally at offset %04x)", offset);
+
+		return 1;
+	}
+
+	pcm_data = self->_data.begin() + offset;
+
+	size = READ_LE_UINT16(pcm_data + SCI0_PCM_SIZE_OFFSET);
+
+	/* Two of the format parameters are fixed by design: */
+	*rate = READ_LE_UINT16(pcm_data + SCI0_PCM_SAMPLE_RATE_OFFSET);
+
+	if (offset + SCI0_PCM_DATA_OFFSET + size != self->_data.size()) {
+		int d = offset + SCI0_PCM_DATA_OFFSET + size - self->_data.size();
+
+		warning("PCM advertizes %d bytes of data, but %d"
+		        " bytes are trailing in the resource",
+		        size, self->_data.size() - (offset + SCI0_PCM_DATA_OFFSET));
+
+		if (d > 0)
+			size -= d; /* Fix this */
+	}
+
+	*xoffset = offset;
+	*xsize = size;
+
+	return 0;
+}
+
+static Audio::AudioStream *makeStream(byte *data, int size, int rate) {
+	debugC(2, kDebugLevelSound, "Playing PCM data of size %d, rate %d\n", size, rate);
+
+	// Duplicate the data
+	byte *sound = (byte *)malloc(size);
+	memcpy(sound, data, size);
+
+	// Convert stream format flags
+	int flags = Audio::Mixer::FLAG_AUTOFREE | Audio::Mixer::FLAG_UNSIGNED;
+	return Audio::makeLinearInputStream(sound, size, rate, flags, 0, 0);
+}
+
+Audio::AudioStream *Sci0SongIterator::getAudioStream() {
+	int rate;
+	int offset;
+	uint size;
+	if (_sci0_get_pcm_data(this, &rate, &offset, &size))
+		return NULL;
+
+	_channel.state = SI_STATE_FINISHED; /* Don't play both PCM and music */
+
+	return makeStream(_data.begin() + offset + SCI0_PCM_DATA_OFFSET, size, rate);
+}
+
+SongIterator *Sci0SongIterator::handleMessage(Message msg) {
+	if (msg._class == _SIMSG_BASE) {
+		switch (msg._type) {
+
+		case _SIMSG_BASEMSG_PRINT:
+			print_tabs_id(msg._arg.i, ID);
+			debugC(2, kDebugLevelSound, "SCI0: dev=%d, active-chan=%d, size=%d, loops=%d\n",
+			        _deviceId, _numActiveChannels, _data.size(), _loops);
+			break;
+
+		case _SIMSG_BASEMSG_SET_LOOPS:
+			_loops = msg._arg.i;
+			break;
+
+		case _SIMSG_BASEMSG_STOP: {
+			songit_id_t sought_id = msg.ID;
+
+			if (sought_id == ID)
+				_channel.state = SI_STATE_FINISHED;
+			break;
+		}
+
+		case _SIMSG_BASEMSG_SET_PLAYMASK: {
+			int i;
+			_deviceId = msg._arg.i;
+
+			/* Set all but the rhytm channel mask bits */
+			_channel.playmask &= ~(1 << MIDI_RHYTHM_CHANNEL);
+
+			for (i = 0; i < MIDI_CHANNELS; i++)
+				if (_data[2 + (i << 1)] & _deviceId
+				        && i != MIDI_RHYTHM_CHANNEL)
+					_channel.playmask |= (1 << i);
+		}
+		break;
+
+		case _SIMSG_BASEMSG_SET_RHYTHM:
+			_channel.playmask &= ~(1 << MIDI_RHYTHM_CHANNEL);
+			if (msg._arg.i)
+				_channel.playmask |= (1 << MIDI_RHYTHM_CHANNEL);
+			break;
+
+		case _SIMSG_BASEMSG_SET_FADE: {
+			fade_params_t *fp = (fade_params_t *) msg._arg.p;
+			fade.action = fp->action;
+			fade.final_volume = fp->final_volume;
+			fade.ticks_per_step = fp->ticks_per_step;
+			fade.step_size = fp->step_size;
+			break;
+		}
+
+		default:
+			return NULL;
+		}
+
+		return this;
+	}
+	return NULL;
+}
+
+int Sci0SongIterator::getTimepos() {
+	return _channel.total_timepos;
+}
+
+Sci0SongIterator::Sci0SongIterator(byte *data, uint size, songit_id_t id)
+ : BaseSongIterator(data, size, id) {
+	channel_mask = 0xffff;	// Allocate all channels by default
+	_channel.state = SI_STATE_UNINITIALISED;
+
+	for (int i = 0; i < MIDI_CHANNELS; i++)
+		_polyphony[i] = data[1 + (i << 1)];
+
+	init();
+}
+
+void Sci0SongIterator::init() {
+	fade.action = FADE_ACTION_NONE;
+	_resetflag = 0;
+	_loops = 0;
+	priority = 0;
+
+	_ccc = 0; /* Reset cumulative cue counter */
+	_numActiveChannels = 1;
+	_channel.init(0, SCI0_MIDI_OFFSET, _data.size());
+	_channel.resetSynthChannels();
+
+	if (_data[0] == 2) /* Do we have an embedded PCM? */
+		_channel.state = SI_STATE_PCM;
+}
+
+SongIterator *Sci0SongIterator::clone(int delta) {
+	Sci0SongIterator *newit = new Sci0SongIterator(*this);
+	return newit;
+}
+
+
+/***************************/
+/*-- SCI1 song iterators --*/
+/***************************/
+
+#define SCI01_INVALID_DEVICE 0xff
+
+/* Second index determines whether PCM output is supported */
+static const int sci0_to_sci1_device_map[][2] = {
+	{0x06, 0x0c}, /* MT-32 */
+	{0xff, 0xff}, /* YM FB-01 */
+	{0x00, 0x00}, /* CMS/Game Blaster-- we assume OPL/2 here... */
+	{0xff, 0xff}, /* Casio MT540/CT460 */
+	{0x13, 0x13}, /* Tandy 3-voice */
+	{0x12, 0x12}, /* PC speaker */
+	{0xff, 0xff},
+	{0xff, 0xff},
+}; /* Maps bit number to device ID */
+
+int Sci1SongIterator::initSample(const int offset) {
+	Sci1Sample sample;
+	int rate;
+	int length;
+	int begin;
+	int end;
+
+	CHECK_FOR_END_ABSOLUTE((uint)offset + 10);
+	if (_data[offset + 1] != 0)
+		warning("[iterator-1] In sample at offset 0x04x: Byte #1 is %02x instead of zero",
+		          _data[offset + 1]);
+
+	rate = (int16)READ_LE_UINT16(_data.begin() + offset + 2);
+	length = READ_LE_UINT16(_data.begin() + offset + 4);
+	begin = (int16)READ_LE_UINT16(_data.begin() + offset + 6);
+	end = (int16)READ_LE_UINT16(_data.begin() + offset + 8);
+
+	CHECK_FOR_END_ABSOLUTE((uint)(offset + 10 + length));
+
+	sample.delta = begin;
+	sample.size = length;
+	sample._data = _data.begin() + offset + 10;
+
+#ifdef DEBUG_VERBOSE
+	fprintf(stderr, "[SAMPLE] %x/%x/%x/%x l=%x\n",
+	        offset + 10, begin, end, _data.size(), length);
+#endif
+
+	sample.rate = rate;
+
+	sample.announced = false;
+
+	/* Insert into the sample list at the right spot, keeping it sorted by delta */
+	Common::List<Sci1Sample>::iterator seeker = _samples.begin();
+	while (seeker != _samples.end() && seeker->delta < begin)
+		++seeker;
+	_samples.insert(seeker, sample);
+
+	return 0; /* Everything's fine */
+}
+
+int Sci1SongIterator::initSong() {
+	int last_time;
+	uint offset = 0;
+	_numChannels = 0;
+	_samples.clear();
+//	_deviceId = 0x0c;
+
+	if (_data[offset] == 0xf0) {
+		priority = _data[offset + 1];
+
+		offset += 8;
+	}
+
+	while (_data[offset] != 0xff
+	        && _data[offset] != _deviceId) {
+		offset++;
+		CHECK_FOR_END_ABSOLUTE(offset + 1);
+		while (_data[offset] != 0xff) {
+			CHECK_FOR_END_ABSOLUTE(offset + 7);
+			offset += 6;
+		}
+		offset++;
+	}
+
+	if (_data[offset] == 0xff) {
+		warning("[iterator] Song does not support hardware 0x%02x", _deviceId);
+		return 1;
+	}
+
+	offset++;
+
+	while (_data[offset] != 0xff) { /* End of list? */
+		uint track_offset;
+		int end;
+		offset += 2;
+
+		CHECK_FOR_END_ABSOLUTE(offset + 4);
+
+		track_offset = READ_LE_UINT16(_data.begin() + offset);
+		end = READ_LE_UINT16(_data.begin() + offset + 2);
+
+		CHECK_FOR_END_ABSOLUTE(track_offset - 1);
+
+		if (_data[track_offset] == 0xfe) {
+			if (initSample(track_offset))
+				return 1; /* Error */
+		} else {
+			/* Regular MIDI channel */
+			if (_numChannels >= MIDI_CHANNELS) {
+				warning("[iterator] Song has more than %d channels, cutting them off",
+				          MIDI_CHANNELS);
+				break; /* Scan for remaining samples */
+			} else {
+				int channel_nr = _data[track_offset] & 0xf;
+				SongIteratorChannel &channel = _channels[_numChannels++];
+
+				/*
+				if (_data[track_offset] & 0xf0)
+					printf("Channel %d has mapping bits %02x\n",
+					       channel_nr, _data[track_offset] & 0xf0);
+				*/
+
+				// Add 2 to skip over header bytes */
+				channel.init(channel_nr, track_offset + 2, track_offset + end);
+				channel.resetSynthChannels();
+
+				_polyphony[_numChannels - 1] = _data[channel.offset - 1] & 15;
+
+				channel.playmask = ~0; /* Enable all */
+				channel_mask |= (1 << channel_nr);
+
+				CHECK_FOR_END_ABSOLUTE(offset + end);
+			}
+		}
+		offset += 4;
+		CHECK_FOR_END_ABSOLUTE(offset);
+	}
+
+	/* Now ensure that sample deltas are relative to the previous sample */
+	last_time = 0;
+	_numActiveChannels = _numChannels;
+	_numLoopedChannels = 0;
+
+	for (Common::List<Sci1Sample>::iterator seeker = _samples.begin();
+			seeker != _samples.end(); ++seeker) {
+		int prev_last_time = last_time;
+		//printf("[iterator] Detected sample: %d Hz, %d bytes at time %d\n",
+		//          seeker->format.rate, seeker->size, seeker->delta);
+		last_time = seeker->delta;
+		seeker->delta -= prev_last_time;
+	}
+
+	return 0; /* Success */
+}
+
+int Sci1SongIterator::getSmallestDelta() const {
+	int d = -1;
+	for (int i = 0; i < _numChannels; i++)
+		if (_channels[i].state == SI_STATE_COMMAND
+		        && (d == -1 || _channels[i].delay < d))
+			d = _channels[i].delay;
+
+	if (!_samples.empty() && _samples.begin()->delta < d)
+		return _samples.begin()->delta;
+	else
+		return d;
+}
+
+void Sci1SongIterator::updateDelta(int delta) {
+	if (!_samples.empty())
+		_samples.begin()->delta -= delta;
+
+	for (int i = 0; i < _numChannels; i++)
+		if (_channels[i].state == SI_STATE_COMMAND)
+			_channels[i].delay -= delta;
+}
+
+bool Sci1SongIterator::noDeltaTime() const {
+	for (int i = 0; i < _numChannels; i++)
+		if (_channels[i].state == SI_STATE_DELTA_TIME)
+			return false;
+	return true;
+}
+
+#define COMMAND_INDEX_NONE -1
+#define COMMAND_INDEX_PCM -2
+
+int Sci1SongIterator::getCommandIndex() const {
+	/* Determine the channel # of the next active event, or -1 */
+	int i;
+	int base_delay = 0x7ffffff;
+	int best_chan = COMMAND_INDEX_NONE;
+
+	for (i = 0; i < _numChannels; i++)
+		if ((_channels[i].state != SI_STATE_PENDING)
+		        && (_channels[i].state != SI_STATE_FINISHED))  {
+
+			if ((_channels[i].state == SI_STATE_DELTA_TIME)
+			        && (_channels[i].delay == 0))
+				return i;
+			/* First, read all unknown delta times */
+
+			if (_channels[i].delay < base_delay) {
+				best_chan = i;
+				base_delay = _channels[i].delay;
+			}
+		}
+
+	if (!_samples.empty() && base_delay >= _samples.begin()->delta)
+		return COMMAND_INDEX_PCM;
+
+	return best_chan;
+}
+
+
+Audio::AudioStream *Sci1SongIterator::getAudioStream() {
+	Common::List<Sci1Sample>::iterator sample = _samples.begin();
+	if (sample != _samples.end() && sample->delta <= 0) {
+		Audio::AudioStream *feed = makeStream(sample->_data, sample->size, sample->rate);
+		_samples.erase(sample);
+
+		return feed;
+	} else
+		return NULL;
+}
+
+int Sci1SongIterator::nextCommand(byte *buf, int *result) {
+
+	if (!_initialised) {
+		//printf("[iterator] DEBUG: Initialising for %d\n", _deviceId);
+		_initialised = true;
+		if (initSong())
+			return SI_FINISHED;
+	}
+
+
+	if (_delayRemaining) {
+		int delay = _delayRemaining;
+		_delayRemaining = 0;
+		return delay;
+	}
+
+	int retval = 0;
+	do {	 /* All delays must be processed separately */
+		int chan = getCommandIndex();
+
+		if (chan == COMMAND_INDEX_NONE) {
+			return SI_FINISHED;
+		}
+
+		if (chan == COMMAND_INDEX_PCM) {
+
+			if (_samples.begin()->announced) {
+				/* Already announced; let's discard it */
+				Audio::AudioStream *feed = getAudioStream();
+				delete feed;
+			} else {
+				int delay = _samples.begin()->delta;
+
+				if (delay) {
+					updateDelta(delay);
+					return delay;
+				}
+				/* otherwise we're touching a PCM */
+				_samples.begin()->announced = true;
+				return SI_PCM;
+			}
+		} else { /* Not a PCM */
+
+			retval = processMidi(buf, result,
+			                     &(_channels[chan]),
+			                     PARSE_FLAG_LOOPS_UNLIMITED);
+
+			if (retval == SI_LOOP) {
+				_numLoopedChannels++;
+				_channels[chan].state = SI_STATE_PENDING;
+				_channels[chan].delay = 0;
+
+				if (_numLoopedChannels == _numActiveChannels) {
+					int i;
+
+					/* Everyone's ready: Let's loop */
+					for (i = 0; i < _numChannels; i++)
+						if (_channels[i].state == SI_STATE_PENDING)
+							_channels[i].state = SI_STATE_DELTA_TIME;
+
+					_numLoopedChannels = 0;
+					return SI_LOOP;
+				}
+			} else if (retval == SI_FINISHED) {
+#ifdef DEBUG
+				fprintf(stderr, "FINISHED some channel\n");
+#endif
+			} else if (retval > 0) {
+				int sd ;
+				sd = getSmallestDelta();
+
+				if (noDeltaTime() && sd) {
+					/* No other channel is ready */
+					updateDelta(sd);
+
+					/* Only from here do we return delta times */
+					return sd;
+				}
+			}
+
+		} /* Not a PCM */
+
+	} while (retval > 0);
+
+	return retval;
+}
+
+SongIterator *Sci1SongIterator::handleMessage(Message msg) {
+	if (msg._class == _SIMSG_BASE) { /* May extend this in the future */
+		switch (msg._type) {
+
+		case _SIMSG_BASEMSG_PRINT: {
+			int playmask = 0;
+			int i;
+
+			for (i = 0; i < _numChannels; i++)
+				playmask |= _channels[i].playmask;
+
+			print_tabs_id(msg._arg.i, ID);
+			debugC(2, kDebugLevelSound, "SCI1: chan-nr=%d, playmask=%04x\n",
+			        _numChannels, playmask);
+		}
+		break;
+
+		case _SIMSG_BASEMSG_STOP: {
+			songit_id_t sought_id = msg.ID;
+			int i;
+
+			if (sought_id == ID) {
+				ID = 0;
+
+				for (i = 0; i < _numChannels; i++)
+					_channels[i].state = SI_STATE_FINISHED;
+			}
+			break;
+		}
+
+		case _SIMSG_BASEMSG_SET_PLAYMASK:
+			if (msg.ID == ID) {
+				channel_mask = 0;
+
+				_deviceId
+				= sci0_to_sci1_device_map
+				  [sci_ffs(msg._arg.i & 0xff) - 1]
+				  [g_system->getMixer()->isReady()]
+				  ;
+
+				if (_deviceId == 0xff) {
+					warning("[iterator] Device %d(%d) not supported",
+					          msg._arg.i & 0xff, g_system->getMixer()->isReady());
+				}
+				if (_initialised) {
+					int i;
+					int toffset = -1;
+
+					for (i = 0; i < _numChannels; i++)
+						if (_channels[i].state != SI_STATE_FINISHED
+						        && _channels[i].total_timepos > toffset) {
+							toffset = _channels[i].total_timepos
+							          + _channels[i].timepos_increment
+							          - _channels[i].delay;
+						}
+
+					/* Find an active channel so that we can
+					** get the correct time offset  */
+
+					initSong();
+
+					toffset -= _delayRemaining;
+					_delayRemaining = 0;
+
+					if (toffset > 0)
+						return new_fast_forward_iterator(this, toffset);
+				} else {
+					initSong();
+					_initialised = true;
+				}
+
+				break;
+
+			}
+
+		case _SIMSG_BASEMSG_SET_LOOPS:
+			if (msg.ID == ID)
+				_loops = (msg._arg.i > 32767) ? 99 : 0;
+			/* 99 is arbitrary, but we can't use '1' because of
+			** the way we're testing in the decoding section.  */
+			break;
+
+		case _SIMSG_BASEMSG_SET_HOLD:
+			_hold = msg._arg.i;
+			break;
+		case _SIMSG_BASEMSG_SET_RHYTHM:
+			/* Ignore */
+			break;
+
+		case _SIMSG_BASEMSG_SET_FADE: {
+			fade_params_t *fp = (fade_params_t *) msg._arg.p;
+			fade.action = fp->action;
+			fade.final_volume = fp->final_volume;
+			fade.ticks_per_step = fp->ticks_per_step;
+			fade.step_size = fp->step_size;
+			break;
+		}
+
+		default:
+			warning("Unsupported command %d to SCI1 iterator", msg._type);
+		}
+		return this;
+	}
+	return NULL;
+}
+
+Sci1SongIterator::Sci1SongIterator(byte *data, uint size, songit_id_t id)
+ : BaseSongIterator(data, size, id) {
+	channel_mask = 0; // Defer channel allocation
+
+	for (int i = 0; i < MIDI_CHANNELS; i++)
+		_polyphony[i] = 0; // Unknown
+
+	init();
+}
+
+void Sci1SongIterator::init() {
+	fade.action = FADE_ACTION_NONE;
+	_resetflag = 0;
+	_loops = 0;
+	priority = 0;
+
+	_ccc = 0;
+	_deviceId = 0x00; // Default to Sound Blaster/Adlib for purposes of cue computation
+	_numChannels = 0;
+	_initialised = false;
+	_delayRemaining = 0;
+	_loops = 0;
+	_hold = 0;
+	memset(_polyphony, 0, sizeof(_polyphony));
+}
+
+Sci1SongIterator::~Sci1SongIterator() {
+}
+
+
+SongIterator *Sci1SongIterator::clone(int delta) {
+	Sci1SongIterator *newit = new Sci1SongIterator(*this);
+	newit->_delayRemaining = delta;
+	return newit;
+}
+
+int Sci1SongIterator::getTimepos() {
+	int max = 0;
+	int i;
+
+	for (i = 0; i < _numChannels; i++)
+		if (_channels[i].total_timepos > max)
+			max = _channels[i].total_timepos;
+
+	return max;
+}
+
+/**
+ * A song iterator with the purpose of sending notes-off channel commands.
+ */
+class CleanupSongIterator : public SongIterator {
+public:
+	CleanupSongIterator(uint channels) {
+		channel_mask = channels;
+		ID = 17;
+	}
+
+	int nextCommand(byte *buf, int *result);
+	Audio::AudioStream *getAudioStream() { return NULL; }
+	SongIterator *handleMessage(Message msg);
+	int getTimepos() { return 0; }
+	SongIterator *clone(int delta) { return new CleanupSongIterator(*this); }
+};
+
+SongIterator *CleanupSongIterator::handleMessage(Message msg) {
+	if (msg._class == _SIMSG_BASEMSG_PRINT && msg._type == _SIMSG_BASEMSG_PRINT) {
+		print_tabs_id(msg._arg.i, ID);
+		debugC(2, kDebugLevelSound, "CLEANUP\n");
+	}
+
+	return NULL;
+}
+
+int CleanupSongIterator::nextCommand(byte *buf, int *result) {
+	/* Task: Return channel-notes-off for each channel */
+	if (channel_mask) {
+		int bs = sci_ffs(channel_mask) - 1;
+
+		channel_mask &= ~(1 << bs);
+		buf[0] = 0xb0 | bs; /* Controller */
+		buf[1] = SCI_MIDI_CHANNEL_NOTES_OFF;
+		buf[2] = 0; /* Hmm... */
+		*result = 3;
+		return 0;
+	} else
+		return SI_FINISHED;
+}
+
+/**********************/
+/*-- Timer iterator --*/
+/**********************/
+int TimerSongIterator::nextCommand(byte *buf, int *result) {
+	if (_delta) {
+		int d = _delta;
+		_delta = 0;
+		return d;
+	}
+	return SI_FINISHED;
+}
+
+SongIterator *new_timer_iterator(int delta) {
+	return new TimerSongIterator(delta);
+}
+
+/**********************************/
+/*-- Fast-forward song iterator --*/
+/**********************************/
+
+int FastForwardSongIterator::nextCommand(byte *buf, int *result) {
+	if (_delta <= 0)
+		return SI_MORPH; /* Did our duty */
+
+	while (1) {
+		int rv = _delegate->nextCommand(buf, result);
+
+		if (rv > 0) {
+			/* Subtract from the delta we want to wait */
+			_delta -= rv;
+
+			/* Done */
+			if (_delta < 0)
+				return -_delta;
+		}
+
+		if (rv <= 0)
+			return rv;
+	}
+}
+
+Audio::AudioStream *FastForwardSongIterator::getAudioStream() {
+	return _delegate->getAudioStream();
+}
+
+SongIterator *FastForwardSongIterator::handleMessage(Message msg) {
+	if (msg._class == _SIMSG_PLASTICWRAP) {
+		assert(msg._type == _SIMSG_PLASTICWRAP_ACK_MORPH);
+
+		if (_delta <= 0) {
+			SongIterator *it = _delegate;
+			delete this;
+			return it;
+		}
+
+		warning("[ff-iterator] Morphing without need");
+		return this;
+	}
+
+	if (msg._class == _SIMSG_BASE && msg._type == _SIMSG_BASEMSG_PRINT) {
+		print_tabs_id(msg._arg.i, ID);
+		debugC(2, kDebugLevelSound, "FASTFORWARD:\n");
+		msg._arg.i++;
+	}
+
+	// And continue with the delegate
+	songit_handle_message(&_delegate, msg);
+
+	return NULL;
+}
+
+
+int FastForwardSongIterator::getTimepos() {
+	return _delegate->getTimepos();
+}
+
+FastForwardSongIterator::FastForwardSongIterator(SongIterator *capsit, int delta)
+	: _delegate(capsit), _delta(delta) {
+
+	channel_mask = capsit->channel_mask;
+}
+
+SongIterator *FastForwardSongIterator::clone(int delta) {
+	FastForwardSongIterator *newit = new FastForwardSongIterator(*this);
+	newit->_delegate = _delegate->clone(delta);
+	return newit;
+}
+
+SongIterator *new_fast_forward_iterator(SongIterator *capsit, int delta) {
+	if (capsit == NULL)
+		return NULL;
+
+	FastForwardSongIterator *it = new FastForwardSongIterator(capsit, delta);
+	return it;
+}
+
+
+/********************/
+/*-- Tee iterator --*/
+/********************/
+
+
+static void song_iterator_add_death_listener(SongIterator *it, TeeSongIterator *client) {
+	for (int i = 0; i < SONGIT_MAX_LISTENERS; ++i) {
+		if (it->_deathListeners[i] == 0) {
+			it->_deathListeners[i] = client;
+			return;
+		}
+	}
+	error("FATAL: Too many death listeners for song iterator");
+}
+
+static void song_iterator_remove_death_listener(SongIterator *it, TeeSongIterator *client) {
+	for (int i = 0; i < SONGIT_MAX_LISTENERS; ++i) {
+		if (it->_deathListeners[i] == client) {
+			it->_deathListeners[i] = 0;
+			return;
+		}
+	}
+}
+
+static void song_iterator_transfer_death_listeners(SongIterator *it, SongIterator *it_from) {
+	for (int i = 0; i < SONGIT_MAX_LISTENERS; ++i) {
+		if (it_from->_deathListeners[i])
+			song_iterator_add_death_listener(it, it_from->_deathListeners[i]);
+		it_from->_deathListeners[i] = 0;
+	}
+}
+
+static void songit_tee_death_notification(TeeSongIterator *self, SongIterator *corpse) {
+	if (corpse == self->_children[TEE_LEFT].it) {
+		self->_status &= ~TEE_LEFT_ACTIVE;
+		self->_children[TEE_LEFT].it = NULL;
+	} else if (corpse == self->_children[TEE_RIGHT].it) {
+		self->_status &= ~TEE_RIGHT_ACTIVE;
+		self->_children[TEE_RIGHT].it = NULL;
+	} else {
+		error("songit_tee_death_notification() failed: Breakpoint in %s, line %d", __FILE__, __LINE__);
+	}
+}
+
+TeeSongIterator::TeeSongIterator(SongIterator *left, SongIterator *right) {
+	int i;
+	int firstfree = 1; /* First free channel */
+	int incomplete_map = 0;
+
+	_readyToMorph = false;
+	_status = TEE_LEFT_ACTIVE | TEE_RIGHT_ACTIVE;
+
+	_children[TEE_LEFT].it = left;
+	_children[TEE_RIGHT].it = right;
+
+	/* Default to lhs channels */
+	channel_mask = left->channel_mask;
+	for (i = 0; i < 16; i++)
+		if (channel_mask & (1 << i) & right->channel_mask
+		        && (i != MIDI_RHYTHM_CHANNEL) /* Share rhythm */) { /*conflict*/
+			while ((firstfree == MIDI_RHYTHM_CHANNEL)
+			        /* Either if it's the rhythm channel or if it's taken */
+			        || (firstfree < MIDI_CHANNELS
+			            && ((1 << firstfree) & channel_mask)))
+				++firstfree;
+
+			if (firstfree == MIDI_CHANNELS) {
+				incomplete_map = 1;
+				//warning("[songit-tee <%08lx,%08lx>] Could not remap right channel #%d: Out of channels",
+				//        left->ID, right->ID, i);
+			} else {
+				_children[TEE_RIGHT].it->channel_remap[i] = firstfree;
+
+				channel_mask |= (1 << firstfree);
+			}
+		}
+#ifdef DEBUG_TEE_ITERATOR
+	if (incomplete_map) {
+		int c;
+		fprintf(stderr, "[songit-tee <%08lx,%08lx>] Channels:"
+		        " %04x <- %04x | %04x\n",
+		        left->ID, right->ID,
+		        channel_mask,
+		        left->channel_mask, right->channel_mask);
+		for (c = 0 ; c < 2; c++)
+			for (i = 0 ; i < 16; i++)
+				fprintf(stderr, "  map [%d][%d] -> %d\n",
+				        c, i, _children[c].it->channel_remap[i]);
+	}
+#endif
+
+
+	song_iterator_add_death_listener(left, this);
+	song_iterator_add_death_listener(right, this);
+}
+
+TeeSongIterator::~TeeSongIterator() {
+	// When we die, remove any listeners from our children
+	if (_children[TEE_LEFT].it) {
+		song_iterator_remove_death_listener(_children[TEE_LEFT].it, this);
+	}
+
+	if (_children[TEE_RIGHT].it) {
+		song_iterator_remove_death_listener(_children[TEE_RIGHT].it, this);
+	}
+}
+
+
+int TeeSongIterator::nextCommand(byte *buf, int *result) {
+	static const int ready_masks[2] = {TEE_LEFT_READY, TEE_RIGHT_READY};
+	static const int active_masks[2] = {TEE_LEFT_ACTIVE, TEE_RIGHT_ACTIVE};
+	static const int pcm_masks[2] = {TEE_LEFT_PCM, TEE_RIGHT_PCM};
+	int i;
+	int retid;
+
+#ifdef DEBUG_TEE_ITERATOR
+	fprintf(stderr, "[Tee] %02x\n", _status);
+#endif
+
+	if (!(_status & (TEE_LEFT_ACTIVE | TEE_RIGHT_ACTIVE)))
+		/* None is active? */
+		return SI_FINISHED;
+
+	if (_readyToMorph)
+		return SI_MORPH;
+
+	if ((_status & (TEE_LEFT_ACTIVE | TEE_RIGHT_ACTIVE))
+	        != (TEE_LEFT_ACTIVE | TEE_RIGHT_ACTIVE)) {
+		/* Not all are is active? */
+		int which = 0;
+#ifdef DEBUG_TEE_ITERATOR
+		fprintf(stderr, "\tRequesting transformation...\n");
+#endif
+		if (_status & TEE_LEFT_ACTIVE)
+			which = TEE_LEFT;
+		else if (_status & TEE_RIGHT_ACTIVE)
+			which = TEE_RIGHT;
+		memcpy(buf, _children[which].buf, sizeof(buf));
+		*result = _children[which].result;
+		_readyToMorph = true;
+		return _children[which].retval;
+	}
+
+	/* First, check for unreported PCMs */
+	for (i = TEE_LEFT; i <= TEE_RIGHT; i++)
+		if ((_status & (ready_masks[i] | pcm_masks[i]))
+		        == (ready_masks[i] | pcm_masks[i])) {
+			_status &= ~ready_masks[i];
+			return SI_PCM;
+		}
+
+	for (i = TEE_LEFT; i <= TEE_RIGHT; i++)
+		if (!(_status & ready_masks[i])) {
+
+			/* Buffers aren't ready yet */
+			_children[i].retval =
+			    songit_next(&(_children[i].it),
+			                _children[i].buf,
+			                &(_children[i].result),
+			                IT_READER_MASK_ALL
+			                | IT_READER_MAY_FREE
+			                | IT_READER_MAY_CLEAN);
+
+			_status |= ready_masks[i];
+#ifdef DEBUG_TEE_ITERATOR
+			fprintf(stderr, "\t Must check %d: %d\n", i, _children[i].retval);
+#endif
+
+			if (_children[i].retval == SI_ABSOLUTE_CUE ||
+			        _children[i].retval == SI_RELATIVE_CUE)
+				return _children[i].retval;
+			if (_children[i].retval == SI_FINISHED) {
+				_status &= ~active_masks[i];
+				/* Recurse to complete */
+#ifdef DEBUG_TEE_ITERATOR
+				fprintf(stderr, "\t Child %d signalled completion, recursing w/ status %02x\n", i, _status);
+#endif
+				return nextCommand(buf, result);
+			} else if (_children[i].retval == SI_PCM) {
+				_status |= pcm_masks[i];
+				_status &= ~ready_masks[i];
+				return SI_PCM;
+			}
+		}
+
+
+	/* We've already handled PCM, MORPH and FINISHED, CUEs & LOOP remain */
+
+	retid = TEE_LEFT;
+	if ((_children[TEE_LEFT].retval > 0)
+	        /* Asked to delay */
+	        && (_children[TEE_RIGHT].retval <= _children[TEE_LEFT].retval))
+		/* Is not delaying or not delaying as much */
+		retid = TEE_RIGHT;
+
+#ifdef DEBUG_TEE_ITERATOR
+	fprintf(stderr, "\tl:%d / r:%d / chose %d\n",
+	        _children[TEE_LEFT].retval, _children[TEE_RIGHT].retval, retid);
+#endif
+
+	/* Adjust delta times */
+	if (_children[retid].retval > 0
+	        && _children[1-retid].retval > 0) {
+		if (_children[1-retid].retval
+		        == _children[retid].retval)
+			/* If both _children wait the same amount of time,
+			** we have to re-fetch commands from both  */
+			_status &= ~ready_masks[1-retid];
+		else
+			/* If they don't, we can/must re-use the other
+			** child's delay time  */
+			_children[1-retid].retval
+			-= _children[retid].retval;
+	}
+
+	_status &= ~ready_masks[retid];
+	memcpy(buf, _children[retid].buf, sizeof(buf));
+	*result = _children[retid].result;
+
+	return _children[retid].retval;
+}
+
+Audio::AudioStream *TeeSongIterator::getAudioStream() {
+	static const int pcm_masks[2] = {TEE_LEFT_PCM, TEE_RIGHT_PCM};
+	int i;
+
+	for (i = TEE_LEFT; i <= TEE_RIGHT; i++)
+		if (_status & pcm_masks[i]) {
+			_status &= ~pcm_masks[i];
+			return _children[i].it->getAudioStream();
+		}
+
+	return NULL; // No iterator
+}
+
+SongIterator *TeeSongIterator::handleMessage(Message msg) {
+	if (msg._class == _SIMSG_PLASTICWRAP) {
+		assert(msg._type == _SIMSG_PLASTICWRAP_ACK_MORPH);
+
+		SongIterator *old_it;
+		if (!(_status & (TEE_LEFT_ACTIVE | TEE_RIGHT_ACTIVE))) {
+			delete this;
+			return NULL;
+		} else if (!(_status & TEE_LEFT_ACTIVE)) {
+			delete _children[TEE_LEFT].it;
+			_children[TEE_LEFT].it = 0;
+			old_it = _children[TEE_RIGHT].it;
+			song_iterator_remove_death_listener(old_it, this);
+			song_iterator_transfer_death_listeners(old_it, this);
+			delete this;
+			return old_it;
+		} else if (!(_status & TEE_RIGHT_ACTIVE)) {
+			delete _children[TEE_RIGHT].it;
+			_children[TEE_RIGHT].it = 0;
+			old_it = _children[TEE_LEFT].it;
+			song_iterator_remove_death_listener(old_it, this);
+			song_iterator_transfer_death_listeners(old_it, this);
+			delete this;
+			return old_it;
+		}
+
+		warning("[tee-iterator] Morphing without need");
+		return this;
+	}
+
+	if (msg._class == _SIMSG_BASE && msg._type == _SIMSG_BASEMSG_PRINT) {
+		print_tabs_id(msg._arg.i, ID);
+		debugC(2, kDebugLevelSound, "TEE:\n");
+		msg._arg.i++;
+	}
+
+	// And continue with the children
+	if (_children[TEE_LEFT].it)
+		songit_handle_message(&(_children[TEE_LEFT].it), msg);
+	if (_children[TEE_RIGHT].it)
+		songit_handle_message(&(_children[TEE_RIGHT].it), msg);
+
+	return NULL;
+}
+
+void TeeSongIterator::init() {
+	_status = TEE_LEFT_ACTIVE | TEE_RIGHT_ACTIVE;
+	_children[TEE_LEFT].it->init();
+	_children[TEE_RIGHT].it->init();
+}
+
+SongIterator *TeeSongIterator::clone(int delta) {
+	TeeSongIterator *newit = new TeeSongIterator(*this);
+
+	if (_children[TEE_LEFT].it)
+		newit->_children[TEE_LEFT].it = _children[TEE_LEFT].it->clone(delta);
+	if (_children[TEE_RIGHT].it)
+		newit->_children[TEE_RIGHT].it = _children[TEE_RIGHT].it->clone(delta);
+
+	return newit;
+}
+
+
+/*************************************/
+/*-- General purpose functionality --*/
+/*************************************/
+
+int songit_next(SongIterator **it, byte *buf, int *result, int mask) {
+	int retval;
+
+	if (!*it)
+		return SI_FINISHED;
+
+	do {
+		retval = (*it)->nextCommand(buf, result);
+		if (retval == SI_MORPH) {
+			debugC(2, kDebugLevelSound, "  Morphing %p (stored at %p)\n", (void *)*it, (void *)it);
+			if (!SIMSG_SEND((*it), SIMSG_ACK_MORPH)) {
+				error("SI_MORPH failed. Breakpoint in %s, line %d", __FILE__, __LINE__);
+			} else
+				debugC(2, kDebugLevelSound, "SI_MORPH successful\n");
+		}
+
+		if (retval == SI_FINISHED)
+			debugC(2, kDebugLevelSound, "[song-iterator] Song finished. mask = %04x, cm=%04x\n",
+			        mask, (*it)->channel_mask);
+		if (retval == SI_FINISHED
+		        && (mask & IT_READER_MAY_CLEAN)
+		        && (*it)->channel_mask) { /* This last test will fail
+					       ** with a terminated
+					       ** cleanup iterator */
+			int channel_mask = (*it)->channel_mask;
+
+			SongIterator *old_it = *it;
+			*it = new CleanupSongIterator(channel_mask);
+			for(uint i = 0; i < MIDI_CHANNELS; i++)
+				(*it)->channel_remap[i] = old_it->channel_remap[i];
+			song_iterator_transfer_death_listeners(*it, old_it);
+			if (mask & IT_READER_MAY_FREE)
+				delete old_it;
+			retval = -9999; /* Continue */
+		}
+	} while (!(  /* Until one of the following holds */
+	             (retval > 0 && (mask & IT_READER_MASK_DELAY))
+	             || (retval == 0 && (mask & IT_READER_MASK_MIDI))
+	             || (retval == SI_LOOP && (mask & IT_READER_MASK_LOOP))
+	             || (retval == SI_ABSOLUTE_CUE &&
+	                 (mask & IT_READER_MASK_CUE))
+	             || (retval == SI_RELATIVE_CUE &&
+	                 (mask & IT_READER_MASK_CUE))
+	             || (retval == SI_PCM && (mask & IT_READER_MASK_PCM))
+	             || (retval == SI_FINISHED)
+	         ));
+
+	if (retval == SI_FINISHED && (mask & IT_READER_MAY_FREE)) {
+		delete *it;
+		*it = NULL;
+	}
+
+	return retval;
+}
+
+SongIterator::SongIterator() {
+	ID = 0;
+	channel_mask = 0;
+	fade.action = FADE_ACTION_NONE;
+	priority = 0;
+	memset(_deathListeners, 0, sizeof(_deathListeners));
+
+	// By default, don't remap
+	for (uint i = 0; i < 16; i++)
+		channel_remap[i] = i;
+}
+
+SongIterator::SongIterator(const SongIterator &si) {
+	ID = si.ID;
+	channel_mask = si.channel_mask;
+	fade = si.fade;
+	priority = si.priority;
+	memset(_deathListeners, 0, sizeof(_deathListeners));
+
+	for (uint i = 0; i < 16; i++)
+		channel_remap[i] = si.channel_remap[i];
+}
+
+
+SongIterator::~SongIterator() {
+	for (int i = 0; i < SONGIT_MAX_LISTENERS; ++i)
+		if (_deathListeners[i])
+			songit_tee_death_notification(_deathListeners[i], this);
+}
+
+SongIterator *songit_new(byte *data, uint size, SongIteratorType type, songit_id_t id) {
+	BaseSongIterator *it;
+
+	if (!data || size < 22) {
+		warning("Attempt to instantiate song iterator for null song data");
+		return NULL;
+	}
+
+
+	switch (type) {
+	case SCI_SONG_ITERATOR_TYPE_SCI0:
+		it = new Sci0SongIterator(data, size, id);
+		break;
+
+	case SCI_SONG_ITERATOR_TYPE_SCI1:
+		it = new Sci1SongIterator(data, size, id);
+		break;
+
+	default:
+		/**-- Invalid/unsupported sound resources --**/
+		warning("Attempt to instantiate invalid/unknown song iterator type %d", type);
+		return NULL;
+	}
+
+	return it;
+}
+
+int songit_handle_message(SongIterator **it_reg_p, SongIterator::Message msg) {
+	SongIterator *it = *it_reg_p;
+	SongIterator *newit;
+
+	newit = it->handleMessage(msg);
+
+	if (!newit)
+		return 0; /* Couldn't handle */
+
+	*it_reg_p = newit; /* Might have self-morphed */
+	return 1;
+}
+
+SongIterator *sfx_iterator_combine(SongIterator *it1, SongIterator *it2) {
+	if (it1 == NULL)
+		return it2;
+	if (it2 == NULL)
+		return it1;
+
+	/* Both are non-NULL: */
+	return new TeeSongIterator(it1, it2);
+}
+
+} // End of namespace Sci
+
+#endif	// USE_OLD_MUSIC_FUNCTIONS