Abstraction cleanups/polish, towards merging with trunk

git-svn-id: svn://localhost/ardour2/branches/midi@720 d708f5d6-7413-0410-9779-e7cbd77b26cf

12 files changed, 224 insertions, 312 deletions

diff --git a/libs/ardour/ardour/audio_diskstream.h b/libs/ardour/ardour/audio_diskstream.h
index c4a942a5d7..ec15cf1caf 100644
--- a/libs/ardour/ardour/audio_diskstream.h
+++ b/libs/ardour/ardour/audio_diskstream.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2000 Paul Davis 
+    Copyright (C) 2000-2006 Paul Davis 
 
     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
@@ -14,8 +14,6 @@
     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., 675 Mass Ave, Cambridge, MA 02139, USA.
-
-    $Id: diskstream.h 579 2006-06-12 19:56:37Z essej $
 */
 
 #ifndef __ardour_audio_diskstream_h__
@@ -62,18 +60,12 @@ class AudioDiskstream : public Diskstream
 	AudioDiskstream (Session &, const string& name, Diskstream::Flag f = Recordable);
 	AudioDiskstream (Session &, const XMLNode&);
 
-	void set_io (ARDOUR::IO& io);
-
+	// FIXME
 	AudioDiskstream& ref() { _refcnt++; return *this; }
-	//void unref() { if (_refcnt) _refcnt--; if (_refcnt == 0) delete this; }
-	//uint32_t refcnt() const { return _refcnt; }
 
 	float playback_buffer_load() const;
 	float capture_buffer_load() const;
 
-	//void set_align_style (AlignStyle);
-	//void set_persistent_align_style (AlignStyle);
-
 	string input_source (uint32_t n=0) const {
 		if (n < channels.size()) {
 			return channels[n].source ? channels[n].source->name() : "";
@@ -87,7 +79,6 @@ class AudioDiskstream : public Diskstream
 	}
 
 	void set_record_enabled (bool yn, void *src);
-	//void set_speed (double);
 
 	float peak_power(uint32_t n=0) { 
 		float x = channels[n].peak_power;
@@ -98,16 +89,13 @@ class AudioDiskstream : public Diskstream
 			return minus_infinity();
 		}
 	}
+	
+	AudioPlaylist* audio_playlist () { return dynamic_cast<AudioPlaylist*>(_playlist); }
 
 	int use_playlist (Playlist *);
 	int use_new_playlist ();
 	int use_copy_playlist ();
 
-	void start_scrub (jack_nframes_t where) {} // FIXME?
-	void end_scrub () {} // FIXME?
-
-	Playlist *playlist () { return _playlist; }
-
 	Sample *playback_buffer (uint32_t n=0) {
 		if (n < channels.size())
 			return channels[n].current_playback_buffer;
@@ -137,7 +125,6 @@ class AudioDiskstream : public Diskstream
 
 	void monitor_input (bool);
 
-	// FIXME: these don't belong here
 	static void swap_by_ptr (Sample *first, Sample *last) {
 		while (first < last) {
 			Sample tmp = *first;
@@ -154,11 +141,6 @@ class AudioDiskstream : public Diskstream
 		}
 	}
 
-	//void handle_input_change (IOChange, void *src);
-	
-	//static sigc::signal<void> DiskOverrun;
-	//static sigc::signal<void> DiskUnderrun;
-	//static sigc::signal<void,AudioDiskstream*> AudioDiskstreamCreated;   // XXX use a ref with sigc2
 	static sigc::signal<void,list<AudioFileSource*>*> DeleteSources;
 
 	int set_loop (Location *loc);
@@ -168,8 +150,6 @@ class AudioDiskstream : public Diskstream
 		return _last_capture_regions;
 	}
 
-	void handle_input_change (IOChange, void *src);
-
 	const PBD::ID& id() const { return _id; }
 
 	XMLNode* deprecated_io_node;
@@ -184,7 +164,6 @@ class AudioDiskstream : public Diskstream
 
 	void set_pending_overwrite(bool);
 	int  overwrite_existing_buffers ();
-	void reverse_scrub_buffer (bool to_forward) {} // FIXME?
 	void set_block_size (jack_nframes_t);
 	int  internal_playback_seek (jack_nframes_t distance);
 	int  can_internal_playback_seek (jack_nframes_t distance);
@@ -237,60 +216,30 @@ class AudioDiskstream : public Diskstream
 		jack_nframes_t                     curr_capture_cnt;
 	};
 
-	typedef vector<ChannelInfo> ChannelList;
-
-	/* the two central butler operations */
-
-	int do_flush (char * workbuf, bool force = false);
-	int do_refill (Sample *mixdown_buffer, float *gain_buffer, char *workbuf);
+	/* The two central butler operations */
+	int do_flush (Session::RunContext context, bool force = false);
+	int do_refill () { return _do_refill(_mixdown_buffer, _gain_buffer, _conversion_buffer); }
 	
-	virtual int non_realtime_do_refill() { return do_refill(0, 0, 0); }
+	int do_refill_with_alloc();
 
-	int read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer, char * workbuf, jack_nframes_t& start, jack_nframes_t cnt, 
-		  ChannelInfo& channel_info, int channel, bool reversed);
-
-	/* XXX fix this redundancy ... */
-
-	//void playlist_changed (Change);
-	//void playlist_modified ();
-	void playlist_deleted (Playlist*);
-	void session_controls_changed (Session::ControlType) {} // FIXME?
+	int read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer, char * workbuf,
+		jack_nframes_t& start, jack_nframes_t cnt, 
+		ChannelInfo& channel_info, int channel, bool reversed);
 
 	void finish_capture (bool rec_monitors_input);
-	void clean_up_capture (struct tm&, time_t, bool abort) {} // FIXME?
 	void transport_stopped (struct tm&, time_t, bool abort);
 
-	struct CaptureInfo {
-	    uint32_t start;
-	    uint32_t frames;
-	};
-
-	vector<CaptureInfo*> capture_info;
-	Glib::Mutex  capture_info_lock;
-	
 	void init (Diskstream::Flag);
 
 	void init_channel (ChannelInfo &chan);
 	void destroy_channel (ChannelInfo &chan);
 	
 	int use_new_write_source (uint32_t n=0);
-	int use_new_fade_source (uint32_t n=0) { return 0; } // FIXME?
 
 	int find_and_use_playlist (const string&);
 
 	void allocate_temporary_buffers ();
 
-	int  create_input_port () { return 0; } // FIXME?
-	int  connect_input_port () { return 0; } // FIXME?
-	int  seek_unlocked (jack_nframes_t which_sample) { return 0; } // FIXME?
-
-	int ports_created () { return 0; } // FIXME?
-
-	//bool realtime_set_speed (double, bool global_change);
-	void non_realtime_set_speed ();
-
-	std::list<Region*> _last_capture_regions;
-	std::vector<AudioFileSource*> capturing_sources;
 	int use_pending_capture_data (XMLNode& node);
 
 	void get_input_sources ();
@@ -299,10 +248,26 @@ class AudioDiskstream : public Diskstream
 	void setup_destructive_playlist ();
 	void use_destructive_playlist ();
 
-	ChannelList    channels;
-	AudioPlaylist* _playlist;
 	void engage_record_enable (void* src);
 	void disengage_record_enable (void* src);
+
+	// Working buffers for do_refill (butler thread)
+	static void allocate_working_buffers();
+	static void free_working_buffers();
+
+	static size_t  _working_buffers_size;
+	static Sample* _mixdown_buffer;
+	static gain_t* _gain_buffer;
+	static char*   _conversion_buffer;
+
+	// Uh, /really/ private?  (death to friend classes)
+	int _do_refill (Sample *mixdown_buffer, float *gain_buffer, char *workbuf);
+	
+	
+	std::vector<AudioFileSource*> capturing_sources;
+	
+	typedef vector<ChannelInfo> ChannelList;
+	ChannelList channels;
 };
 
 } // namespace ARDOUR
diff --git a/libs/ardour/ardour/diskstream.h b/libs/ardour/ardour/diskstream.h
index b595879264..ff25127ec9 100644
--- a/libs/ardour/ardour/diskstream.h
+++ b/libs/ardour/ardour/diskstream.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2000 Paul Davis 
+    Copyright (C) 2000-2006 Paul Davis 
 
     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
@@ -52,7 +52,6 @@ class AudioEngine;
 class Send;
 class Session;
 class Playlist;
-//class FileSource;
 class IO;
 
 /* FIXME: There are (obviously) far too many virtual functions in this ATM.
@@ -71,10 +70,10 @@ class Diskstream : public Stateful, public sigc::trackable
 	virtual int set_name (string str, void* src);
 
 	ARDOUR::IO* io() const { return _io; }
-	virtual void set_io (ARDOUR::IO& io) = 0;
+	void set_io (ARDOUR::IO& io);
 
 	virtual Diskstream& ref() { _refcnt++; return *this; }
-	void unref() { if (_refcnt) _refcnt--; if (_refcnt == 0) delete this; }
+	void     unref() { if (_refcnt) _refcnt--; if (_refcnt == 0) delete this; }
 	uint32_t refcnt() const { return _refcnt; }
 
 	virtual float playback_buffer_load() const = 0;
@@ -105,17 +104,15 @@ class Diskstream : public Stateful, public sigc::trackable
 	virtual void punch_in()  {}
 	virtual void punch_out() {}
 
-	virtual void set_speed (double);
-	virtual void non_realtime_set_speed () = 0;
+	void set_speed (double);
+	void non_realtime_set_speed ();
 
-	virtual Playlist *playlist () = 0;
+	Playlist* playlist () { return _playlist; }
+
+	virtual int use_playlist (Playlist *);
 	virtual int use_new_playlist () = 0;
-	virtual int use_playlist (Playlist *) = 0;
 	virtual int use_copy_playlist () = 0;
 
-	virtual void start_scrub (jack_nframes_t where) = 0;
-	virtual void end_scrub () = 0;
-
 	jack_nframes_t current_capture_start() const { return capture_start_frame; }
 	jack_nframes_t current_capture_end()   const { return capture_start_frame + capture_captured; }
 	jack_nframes_t get_capture_start_frame (uint32_t n=0);
@@ -123,7 +120,7 @@ class Diskstream : public Stateful, public sigc::trackable
 	
 	uint32_t n_channels() { return _n_channels; }
 
-	static jack_nframes_t disk_io_frames() { return disk_io_chunk_frames; }
+	static jack_nframes_t disk_io_frames()            { return disk_io_chunk_frames; }
 	static void set_disk_io_chunk_frames (uint32_t n) { disk_io_chunk_frames = n; }
 
 	/* Stateful */
@@ -144,7 +141,7 @@ class Diskstream : public Stateful, public sigc::trackable
 
 	std::list<Region*>& last_capture_regions () { return _last_capture_regions; }
 
-	virtual void handle_input_change (IOChange, void *src);
+	void handle_input_change (IOChange, void *src);
 
 	sigc::signal<void,void*> RecordEnableChanged;
 	sigc::signal<void>       SpeedChanged;
@@ -170,7 +167,6 @@ class Diskstream : public Stateful, public sigc::trackable
 
 	virtual void set_pending_overwrite (bool) = 0;
 	virtual int  overwrite_existing_buffers () = 0;
-	virtual void reverse_scrub_buffer (bool to_forward) = 0;
 	virtual void set_block_size (jack_nframes_t) = 0;
 	virtual int  internal_playback_seek (jack_nframes_t distance) = 0;
 	virtual int  can_internal_playback_seek (jack_nframes_t distance) = 0;
@@ -209,25 +205,21 @@ class Diskstream : public Stateful, public sigc::trackable
 		jack_nframes_t   capture_val;
 	};
 
-	/* the two central butler operations */
-
-	virtual int do_flush (char * workbuf, bool force = false) = 0;
-	//int do_refill (Sample *mixdown_buffer, float *gain_buffer, char *workbuf);
+	/* The two central butler operations */
+	virtual int do_flush (Session::RunContext context, bool force = false) = 0;
+	virtual int do_refill () = 0;
 	
-	virtual int non_realtime_do_refill() = 0;
+	/** For non-butler contexts (allocates temporary working buffers) */
+	virtual int do_refill_with_alloc() = 0;
 
-	//int read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer, char * workbuf, jack_nframes_t& start, jack_nframes_t cnt, 
-	//	  ChannelInfo& channel_info, int channel, bool reversed);
 	
 	/* XXX fix this redundancy ... */
 
 	virtual void playlist_changed (Change);
 	virtual void playlist_modified ();
-	virtual void playlist_deleted (Playlist*) = 0;
-	virtual void session_controls_changed (Session::ControlType) = 0;
+	virtual void playlist_deleted (Playlist*);
 
 	virtual void finish_capture (bool rec_monitors_input) = 0;
-	virtual void clean_up_capture (struct tm&, time_t, bool abort) = 0;
 	virtual void transport_stopped (struct tm&, time_t, bool abort) = 0;
 
 	struct CaptureInfo {
@@ -237,37 +229,23 @@ class Diskstream : public Stateful, public sigc::trackable
 
 	virtual void init (Flag);
 
-	//void init_channel (ChannelInfo &chan);
-	//void destroy_channel (ChannelInfo &chan);
-
 	virtual int use_new_write_source (uint32_t n=0) = 0;
-	virtual int use_new_fade_source (uint32_t n=0) = 0;
 
 	virtual int find_and_use_playlist (const string&) = 0;
 
-	//void allocate_temporary_buffers ();
-
-	virtual int  create_input_port () = 0;
-	virtual int  connect_input_port () = 0;
-	virtual int  seek_unlocked (jack_nframes_t which_sample) = 0;
-
-	virtual int ports_created () = 0;
+	virtual void allocate_temporary_buffers () = 0;
 
 	virtual bool realtime_set_speed (double, bool global_change);
-	//void non_realtime_set_speed ();
 
 	std::list<Region*> _last_capture_regions;
-	//std::vector<FileSource*> capturing_sources;
 	virtual int use_pending_capture_data (XMLNode& node) = 0;
 
 	virtual void get_input_sources () = 0;
 	virtual void check_record_status (jack_nframes_t transport_frame, jack_nframes_t nframes, bool can_record) = 0;
-	//void set_align_style_from_io();
+	virtual void set_align_style_from_io() {}
 	virtual void setup_destructive_playlist () = 0;
-	//void use_destructive_playlist ();
+	virtual void use_destructive_playlist () = 0;
 
-	// Wouldn't hurt for this thing to do on a diet:
-	
 	static jack_nframes_t disk_io_chunk_frames;
 	vector<CaptureInfo*>  capture_info;
 	Glib::Mutex           capture_info_lock;
@@ -279,6 +257,7 @@ class Diskstream : public Stateful, public sigc::trackable
 	ARDOUR::IO*       _io;
 	uint32_t          _n_channels;
 	PBD::ID           _id;
+	Playlist*         _playlist;
 
 	mutable gint             _record_enabled;
 	double                   _visible_speed;
@@ -338,7 +317,6 @@ class Diskstream : public Stateful, public sigc::trackable
 	sigc::connection plgone_connection;
 	
 	unsigned char _flags;
-
 };
 
 }; /* namespace ARDOUR */
diff --git a/libs/ardour/ardour/midi_diskstream.h b/libs/ardour/ardour/midi_diskstream.h
index b6121d1176..5998363d69 100644
--- a/libs/ardour/ardour/midi_diskstream.h
+++ b/libs/ardour/ardour/midi_diskstream.h
@@ -80,9 +80,6 @@ class MidiDiskstream : public Diskstream
 	int use_new_playlist ();
 	int use_copy_playlist ();
 
-	void start_scrub (jack_nframes_t where) {} // FIXME?
-	void end_scrub () {} // FIXME?
-
 	Playlist *playlist () { return _playlist; }
 
 	static sigc::signal<void,list<SMFSource*>*> DeleteSources;
@@ -106,7 +103,6 @@ class MidiDiskstream : public Diskstream
 
 	void set_pending_overwrite(bool);
 	int  overwrite_existing_buffers ();
-	void reverse_scrub_buffer (bool to_forward) {} // FIXME?
 	void set_block_size (jack_nframes_t);
 	int  internal_playback_seek (jack_nframes_t distance);
 	int  can_internal_playback_seek (jack_nframes_t distance);
@@ -134,12 +130,11 @@ class MidiDiskstream : public Diskstream
 
 	MidiPlaylist* _playlist;
 
-	/* the two central butler operations */
-
-	int do_flush (char * workbuf, bool force = false);
-	int do_refill (RawMidi *mixdown_buffer, float *gain_buffer, char *workbuf);
+	/*Tthe two central butler operations */
+	int do_flush (Session::RunContext context, bool force = false) { return 0; }
+	int do_refill () { return 0; }
 	
-	virtual int non_realtime_do_refill() { return do_refill(0, 0, 0); }
+	int do_refill_with_alloc() { return 0; }
 
 	int read (RawMidi* buf, RawMidi* mixdown_buffer, char * workbuf, jack_nframes_t& start, jack_nframes_t cnt, bool reversed);
 
@@ -148,10 +143,8 @@ class MidiDiskstream : public Diskstream
 	//void playlist_changed (Change);
 	//void playlist_modified ();
 	void playlist_deleted (Playlist*);
-	void session_controls_changed (Session::ControlType) {} // FIXME?
 
 	void finish_capture (bool rec_monitors_input);
-	void clean_up_capture (struct tm&, time_t, bool abort) {} // FIXME?
 	void transport_stopped (struct tm&, time_t, bool abort);
 
 	struct CaptureInfo {
@@ -162,18 +155,11 @@ class MidiDiskstream : public Diskstream
 	void init (Diskstream::Flag);
 
 	int use_new_write_source (uint32_t n=0);
-	int use_new_fade_source (uint32_t n=0) { return 0; } // FIXME?
 
 	int find_and_use_playlist (const string&);
 
 	void allocate_temporary_buffers ();
 
-	int  create_input_port () { return 0; } // FIXME?
-	int  connect_input_port () { return 0; } // FIXME?
-	int  seek_unlocked (jack_nframes_t which_sample) { return 0; } // FIXME?
-
-	int ports_created () { return 0; } // FIXME?
-
 	//bool realtime_set_speed (double, bool global_change);
 	void non_realtime_set_speed ();
 
diff --git a/libs/ardour/ardour/playlist.h b/libs/ardour/ardour/playlist.h
index ca760a5ad5..add253982f 100644
--- a/libs/ardour/ardour/playlist.h
+++ b/libs/ardour/ardour/playlist.h
@@ -110,16 +110,15 @@ class Playlist : public Stateful, public StateManager {
 	int set_state (const XMLNode&);
 	XMLNode& get_template ();
 
-	sigc::signal<void,Region *> RegionAdded;
-	sigc::signal<void,Region *> RegionRemoved;
-
+	sigc::signal<void,Region *>       RegionAdded;
+	sigc::signal<void,Region *>       RegionRemoved;
 	sigc::signal<void,Playlist*,bool> InUse;
-	sigc::signal<void>            Modified;
-	sigc::signal<void>            NameChanged;
-	sigc::signal<void>            LengthChanged;
-	sigc::signal<void>            LayeringChanged;
-	sigc::signal<void,Playlist *> GoingAway;
-	sigc::signal<void>            StatePushed;
+	sigc::signal<void>                Modified;
+	sigc::signal<void>                NameChanged;
+	sigc::signal<void>                LengthChanged;
+	sigc::signal<void>                LayeringChanged;
+	sigc::signal<void,Playlist *>     GoingAway;
+	sigc::signal<void>                StatePushed;
 
 	static sigc::signal<void,Playlist*> PlaylistCreated;
 
diff --git a/libs/ardour/ardour/region.h b/libs/ardour/ardour/region.h
index 68ac55df67..a138f66042 100644
--- a/libs/ardour/ardour/region.h
+++ b/libs/ardour/ardour/region.h
@@ -145,6 +145,8 @@ class Region : public Stateful, public StateManager
 	bool overlap_equivalent (const Region&) const;
 	bool region_list_equivalent (const Region&) const;
 	virtual bool source_equivalent (const Region&) const = 0;
+	
+	virtual bool speed_mismatch (float) const = 0;
 
 	/*virtual jack_nframes_t read_at (Sample *buf, Sample *mixdown_buffer, 
 					float *gain_buffer, char * workbuf, jack_nframes_t position, jack_nframes_t cnt, 
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 7bd24b96cc..dd8ec4806a 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -938,7 +938,7 @@ class Session : public sigc::trackable, public Stateful
 	/* buffers for gain and pan */
 
 	gain_t* gain_automation_buffer () const { return _gain_automation_buffer; }
-	pan_t** pan_automation_buffer() const { return _pan_automation_buffer; }
+	pan_t** pan_automation_buffer () const  { return _pan_automation_buffer; }
 
 	/* buffers for conversion */
 	enum RunContext {
diff --git a/libs/ardour/audio_diskstream.cc b/libs/ardour/audio_diskstream.cc
index a3345cf15a..5f6ce05016 100644
--- a/libs/ardour/audio_diskstream.cc
+++ b/libs/ardour/audio_diskstream.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2000-2003 Paul Davis 
+    Copyright (C) 2000-2006 Paul Davis 
 
     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
@@ -14,8 +14,6 @@
     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., 675 Mass Ave, Cambridge, MA 02139, USA.
-
-    $Id: diskstream.cc 567 2006-06-07 14:54:12Z trutkin $
 */
 
 #include <fstream>
@@ -23,6 +21,7 @@
 #include <unistd.h>
 #include <cmath>
 #include <cerrno>
+#include <cassert>
 #include <string>
 #include <climits>
 #include <fcntl.h>
@@ -57,10 +56,14 @@ using namespace PBD;
 
 sigc::signal<void,list<AudioFileSource*>*> AudioDiskstream::DeleteSources;
 
+size_t  AudioDiskstream::_working_buffers_size = 0;
+Sample* AudioDiskstream::_mixdown_buffer       = 0;
+gain_t* AudioDiskstream::_gain_buffer          = 0;
+char*   AudioDiskstream::_conversion_buffer    = 0;
+
 AudioDiskstream::AudioDiskstream (Session &sess, const string &name, Diskstream::Flag flag)
 	: Diskstream(sess, name, flag)
 	, deprecated_io_node(NULL)
-	, _playlist(NULL)
 {
 	/* prevent any write sources from being created */
 
@@ -77,7 +80,6 @@ AudioDiskstream::AudioDiskstream (Session &sess, const string &name, Diskstream:
 AudioDiskstream::AudioDiskstream (Session& sess, const XMLNode& node)
 	: Diskstream(sess, node)
 	, deprecated_io_node(NULL)
-	, _playlist(NULL)
 {
 	in_set_state = true;
 	init (Recordable);
@@ -178,25 +180,33 @@ AudioDiskstream::~AudioDiskstream ()
 {
 	Glib::Mutex::Lock lm (state_lock);
 
-	if (_playlist)
-		_playlist->unref ();
-
-	for (ChannelList::iterator chan = channels.begin(); chan != channels.end(); ++chan) {
+	for (ChannelList::iterator chan = channels.begin(); chan != channels.end(); ++chan)
 		destroy_channel((*chan));
-	}
 	
 	channels.clear();
 }
 
 void
-AudioDiskstream::handle_input_change (IOChange change, void *src)
+AudioDiskstream::allocate_working_buffers()
 {
-	Glib::Mutex::Lock lm (state_lock);
+	assert(disk_io_frames() > 0);
 
-	if (!(input_change_pending & change)) {
-		input_change_pending = IOChange (input_change_pending|change);
-		_session.request_input_change_handling ();
-	}
+	_working_buffers_size = disk_io_frames();
+	_mixdown_buffer       = new Sample[_working_buffers_size];
+	_gain_buffer          = new gain_t[_working_buffers_size];
+	_conversion_buffer    = new char[_working_buffers_size * 4];
+}
+
+void
+AudioDiskstream::free_working_buffers()
+{
+	delete _mixdown_buffer;
+	delete _gain_buffer;
+	delete _conversion_buffer;
+	_working_buffers_size = 0;
+	_mixdown_buffer       = 0;
+	_gain_buffer          = 0;
+	_conversion_buffer    = 0;
 }
 
 void
@@ -312,40 +322,7 @@ AudioDiskstream::use_playlist (Playlist* playlist)
 {
 	assert(dynamic_cast<AudioPlaylist*>(playlist));
 
-	{
-		Glib::Mutex::Lock lm (state_lock);
-
-		if (playlist == _playlist) {
-			return 0;
-		}
-
-		plstate_connection.disconnect();
-		plmod_connection.disconnect ();
-		plgone_connection.disconnect ();
-
-		if (_playlist) {
-			_playlist->unref();
-		}
-			
-		_playlist = dynamic_cast<AudioPlaylist*>(playlist);
-		_playlist->ref();
-
-		if (!in_set_state && recordable()) {
-			reset_write_sources (false);
-		}
-		
-		plstate_connection = _playlist->StateChanged.connect (mem_fun (*this, &AudioDiskstream::playlist_changed));
-		plmod_connection = _playlist->Modified.connect (mem_fun (*this, &AudioDiskstream::playlist_modified));
-		plgone_connection = _playlist->GoingAway.connect (mem_fun (*this, &AudioDiskstream::playlist_deleted));
-	}
-
-	if (!overwrite_queued) {
-		_session.request_overwrite_buffer (this);
-		overwrite_queued = true;
-	}
-	
-	PlaylistChanged (); /* EMIT SIGNAL */
-	_session.set_dirty ();
+	Diskstream::use_playlist(playlist);
 
 	return 0;
 }
@@ -377,6 +354,8 @@ AudioDiskstream::use_new_playlist ()
 int
 AudioDiskstream::use_copy_playlist ()
 {
+	assert(audio_playlist());
+
 	if (destructive()) {
 		return 0;
 	}
@@ -391,7 +370,7 @@ AudioDiskstream::use_copy_playlist ()
 
 	newname = Playlist::bump_name (_playlist->name(), _session);
 	
-	if ((playlist  = new AudioPlaylist (*_playlist, newname)) != 0) {
+	if ((playlist  = new AudioPlaylist (*audio_playlist(), newname)) != 0) {
 		playlist->set_orig_diskstream_id (id());
 		return use_playlist (playlist);
 	} else { 
@@ -399,19 +378,6 @@ AudioDiskstream::use_copy_playlist ()
 	}
 }
 
-
-void
-AudioDiskstream::playlist_deleted (Playlist* pl)
-{
-	/* this catches an ordering issue with session destruction. playlists 
-	   are destroyed before diskstreams. we have to invalidate any handles
-	   we have to the playlist.
-	*/
-
-	_playlist = 0;
-}
-
-
 void
 AudioDiskstream::setup_destructive_playlist ()
 {
@@ -461,36 +427,6 @@ AudioDiskstream::use_destructive_playlist ()
 }
 
 void
-AudioDiskstream::set_io (IO& io)
-{
-	_io = &io;
-	set_align_style_from_io ();
-}
-
-void
-AudioDiskstream::non_realtime_set_speed ()
-{
-	if (_buffer_reallocation_required)
-	{
-		Glib::Mutex::Lock lm (state_lock);
-		allocate_temporary_buffers ();
-
-		_buffer_reallocation_required = false;
-	}
-
-	if (_seek_required) {
-		if (speed() != 1.0f || speed() != -1.0f) {
-			seek ((jack_nframes_t) (_session.transport_frame() * (double) speed()), true);
-		}
-		else {
-			seek (_session.transport_frame(), true);
-		}
-
-		_seek_required = false;
-	}
-}
-
-void
 AudioDiskstream::check_record_status (jack_nframes_t transport_frame, jack_nframes_t nframes, bool can_record)
 {
 	int possibly_recording;
@@ -1054,9 +990,9 @@ AudioDiskstream::seek (jack_nframes_t frame, bool complete_refill)
 	file_frame = frame;
 
 	if (complete_refill) {
-		while ((ret = non_realtime_do_refill ()) > 0);
+		while ((ret = do_refill_with_alloc ()) > 0) ;
 	} else {
-		ret = non_realtime_do_refill ();
+		ret = do_refill_with_alloc ();
 	}
 
 	return ret;
@@ -1148,7 +1084,7 @@ AudioDiskstream::read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer,
 
 		this_read = min(cnt,this_read);
 
-		if (_playlist->read (buf+offset, mixdown_buffer, gain_buffer, workbuf, start, this_read, channel) != this_read) {
+		if (audio_playlist()->read (buf+offset, mixdown_buffer, gain_buffer, workbuf, start, this_read, channel) != this_read) {
 			error << string_compose(_("AudioDiskstream %1: cannot read %2 from playlist at frame %3"), _id, this_read, 
 					 start) << endmsg;
 			return -1;
@@ -1182,14 +1118,27 @@ AudioDiskstream::read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer,
 }
 
 int
-AudioDiskstream::do_refill (Sample* mixdown_buffer, float* gain_buffer, char * workbuf)
+AudioDiskstream::do_refill_with_alloc()
+{
+	Sample* mix_buf  = new Sample[disk_io_chunk_frames];
+	float*  gain_buf = new float[disk_io_chunk_frames];
+	char*   work_buf = new char[disk_io_chunk_frames * 4];
+
+	int ret = _do_refill(mix_buf, gain_buf, work_buf);
+	
+	delete [] mix_buf;
+	delete [] gain_buf;
+	delete [] work_buf;
+
+	return ret;
+}
+
+int
+AudioDiskstream::_do_refill (Sample* mixdown_buffer, float* gain_buffer, char * workbuf)
 {
 	int32_t ret = 0;
 	jack_nframes_t to_read;
 	RingBufferNPT<Sample>::rw_vector vector;
-	bool free_mixdown;
-	bool free_gain;
-	bool free_workbuf;
 	bool reversed = (_visible_speed * _session.transport_speed()) < 0.0f;
 	jack_nframes_t total_space;
 	jack_nframes_t zero_fill;
@@ -1197,6 +1146,10 @@ AudioDiskstream::do_refill (Sample* mixdown_buffer, float* gain_buffer, char * w
 	ChannelList::iterator i;
 	jack_nframes_t ts;
 
+	assert(mixdown_buffer);
+	assert(gain_buffer);
+	assert(workbuf);
+
 	channels.front().playback_buf->get_write_vector (&vector);
 	
 	if ((total_space = vector.len[0] + vector.len[1]) == 0) {
@@ -1303,33 +1256,6 @@ AudioDiskstream::do_refill (Sample* mixdown_buffer, float* gain_buffer, char * w
 			zero_fill = 0;
 		}
 	}
-
-	/* Please note: the code to allocate buffers isn't run
-	   during normal butler thread operation. Its there
-	   for other times when we need to call do_refill()
-	   from somewhere other than the butler thread.
-	*/
-
-	if (mixdown_buffer == 0) {
-		mixdown_buffer = new Sample[disk_io_chunk_frames];
-		free_mixdown = true;
-	} else {
-		free_mixdown = false;
-	}
-
-	if (gain_buffer == 0) {
-		gain_buffer = new float[disk_io_chunk_frames];
-		free_gain = true;
-	} else {
-		free_gain = false;
-	}
-
-	if (workbuf == 0) {
-		workbuf = new char[disk_io_chunk_frames * 4];
-		free_workbuf = true;
-	} else {
-		free_workbuf = false;
-	}
 	
 	jack_nframes_t file_frame_tmp = 0;
 
@@ -1398,22 +1324,15 @@ AudioDiskstream::do_refill (Sample* mixdown_buffer, float* gain_buffer, char * w
 	file_frame = file_frame_tmp;
 
   out:
-	if (free_mixdown) {
-		delete [] mixdown_buffer;
-	}
-	if (free_gain) {
-		delete [] gain_buffer;
-	}
-	if (free_workbuf) {
-		delete [] workbuf;
-	}
 
 	return ret;
 }	
 
 int
-AudioDiskstream::do_flush (char * workbuf, bool force_flush)
+AudioDiskstream::do_flush (Session::RunContext context, bool force_flush)
 {
+	char* workbuf = _session.conversion_buffer(context);
+
 	uint32_t to_write;
 	int32_t ret = 0;
 	RingBufferNPT<Sample>::rw_vector vector;
@@ -1570,7 +1489,7 @@ AudioDiskstream::transport_stopped (struct tm& when, time_t twhen, bool abort_ca
 	*/
 
 	while (more_work && !err) {
-		switch (do_flush ( _session.conversion_buffer(Session::TransportContext), true)) {
+		switch (do_flush (Session::TransportContext, true)) {
 		case 0:
 			more_work = false;
 			break;
diff --git a/libs/ardour/diskstream.cc b/libs/ardour/diskstream.cc
index 4e2bec9850..9fc2ded0ce 100644
--- a/libs/ardour/diskstream.cc
+++ b/libs/ardour/diskstream.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2000-2003 Paul Davis 
+    Copyright (C) 2000-2006 Paul Davis 
 
     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
@@ -55,7 +55,7 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-jack_nframes_t Diskstream::disk_io_chunk_frames;
+jack_nframes_t Diskstream::disk_io_chunk_frames = 0;
 
 sigc::signal<void,Diskstream*>    Diskstream::DiskstreamCreated;
 //sigc::signal<void,list<AudioFileSource*>*> Diskstream::DeleteSources;
@@ -65,13 +65,14 @@ sigc::signal<void>                Diskstream::DiskUnderrun;
 Diskstream::Diskstream (Session &sess, const string &name, Flag flag)
 	: _name (name)
 	, _session (sess)
+	, _playlist(NULL)
 {
 	init (flag);
 }
 	
 Diskstream::Diskstream (Session& sess, const XMLNode& node)
 	: _session (sess)
-	
+	, _playlist(NULL)
 {
 	init (Recordable);
 }
@@ -113,37 +114,28 @@ Diskstream::init (Flag f)
 	_read_data_count = 0;
 	_write_data_count = 0;
 
-	/* there are no channels at this point, so these
-	   two calls just get speed_buffer_size and wrap_buffer
-	   size setup without duplicating their code.
-	*/
-
-	//set_block_size (_session.get_block_size());
-	//allocate_temporary_buffers ();
-
 	pending_overwrite = false;
 	overwrite_frame = 0;
 	overwrite_queued = false;
 	input_change_pending = NoChange;
 
-	//add_channel ();
-	_n_channels = 0;//1;
+	_n_channels = 0;
 }
 
 Diskstream::~Diskstream ()
 {
-	// Taken by child.. assure lock?
+	// Taken by derived class destrctors.. assure lock?
 	//Glib::Mutex::Lock lm (state_lock);
 
-	//if (_playlist) {
-	//	_playlist->unref ();
-	//}
+	if (_playlist)
+		_playlist->unref ();
+}
 
-	//for (ChannelList::iterator chan = channels.begin(); chan != channels.end(); ++chan) {
-	//	destroy_channel((*chan));
-	//}
-	
-	//channels.clear();
+void
+Diskstream::set_io (IO& io)
+{
+	_io = &io;
+	set_align_style_from_io ();
 }
 
 void
@@ -157,6 +149,29 @@ Diskstream::handle_input_change (IOChange change, void *src)
 	}
 }
 
+void
+Diskstream::non_realtime_set_speed ()
+{
+	if (_buffer_reallocation_required)
+	{
+		Glib::Mutex::Lock lm (state_lock);
+		allocate_temporary_buffers ();
+
+		_buffer_reallocation_required = false;
+	}
+
+	if (_seek_required) {
+		if (speed() != 1.0f || speed() != -1.0f) {
+			seek ((jack_nframes_t) (_session.transport_frame() * (double) speed()), true);
+		}
+		else {
+			seek (_session.transport_frame(), true);
+		}
+
+		_seek_required = false;
+	}
+}
+
 bool
 Diskstream::realtime_set_speed (double sp, bool global)
 {
@@ -223,7 +238,6 @@ Diskstream::set_align_style (AlignStyle a)
 		return;
 	}
 
-
 	if (a != _alignment_style) {
 		_alignment_style = a;
 		AlignmentStyleChanged ();
@@ -287,6 +301,47 @@ Diskstream::set_speed (double sp)
 	playlist_modified();
 }
 
+int
+Diskstream::use_playlist (Playlist* playlist)
+{
+	{
+		Glib::Mutex::Lock lm (state_lock);
+
+		if (playlist == _playlist) {
+			return 0;
+		}
+
+		plstate_connection.disconnect();
+		plmod_connection.disconnect ();
+		plgone_connection.disconnect ();
+
+		if (_playlist) {
+			_playlist->unref();
+		}
+			
+		_playlist = playlist;
+		_playlist->ref();
+
+		if (!in_set_state && recordable()) {
+			reset_write_sources (false);
+		}
+		
+		plstate_connection = _playlist->StateChanged.connect (mem_fun (*this, &Diskstream::playlist_changed));
+		plmod_connection = _playlist->Modified.connect (mem_fun (*this, &Diskstream::playlist_modified));
+		plgone_connection = _playlist->GoingAway.connect (mem_fun (*this, &Diskstream::playlist_deleted));
+	}
+
+	if (!overwrite_queued) {
+		_session.request_overwrite_buffer (this);
+		overwrite_queued = true;
+	}
+	
+	PlaylistChanged (); /* EMIT SIGNAL */
+	_session.set_dirty ();
+
+	return 0;
+}
+
 void
 Diskstream::playlist_changed (Change ignored)
 {
@@ -302,6 +357,17 @@ Diskstream::playlist_modified ()
 	} 
 }
 
+void
+Diskstream::playlist_deleted (Playlist* pl)
+{
+	/* this catches an ordering issue with session destruction. playlists 
+	   are destroyed before diskstreams. we have to invalidate any handles
+	   we have to the playlist.
+	*/
+
+	_playlist = 0;
+}
+
 int
 Diskstream::set_name (string str, void *src)
 {
diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index a5853136ea..4602fc8f67 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -388,7 +388,7 @@ MidiDiskstream::read (RawMidi* buf, RawMidi* mixdown_buffer, char * workbuf, jac
 {
 	return 0;
 }
-
+/*
 int
 MidiDiskstream::do_refill (RawMidi* mixdown_buffer, float* gain_buffer, char * workbuf)
 {
@@ -400,7 +400,7 @@ MidiDiskstream::do_flush (char * workbuf, bool force_flush)
 {
 	return 0;
 }
-
+*/
 void
 MidiDiskstream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture)
 {
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index fec674b671..011d1d6237 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -403,6 +403,8 @@ Session::~Session ()
 	for (map<RunContext,char*>::iterator i = _conversion_buffers.begin(); i != _conversion_buffers.end(); ++i) {
 		delete [] (i->second);
 	}
+
+	AudioDiskstream::free_working_buffers();
 	
 #undef TRACK_DESTRUCTION
 #ifdef TRACK_DESTRUCTION
@@ -2105,7 +2107,7 @@ void
 Session::add_diskstream (Diskstream* dstream)
 {
 	/* need to do this in case we're rolling at the time, to prevent false underruns */
-	dstream->non_realtime_do_refill();
+	dstream->do_refill_with_alloc();
 	
 	{ 
 		Glib::RWLock::WriterLock lm (diskstream_lock);
diff --git a/libs/ardour/session_butler.cc b/libs/ardour/session_butler.cc
index f0a2af0a83..6509a783bb 100644
--- a/libs/ardour/session_butler.cc
+++ b/libs/ardour/session_butler.cc
@@ -170,11 +170,6 @@ Session::butler_thread_work ()
 	bool disk_work_outstanding = false;
 	DiskstreamList::iterator i;
 
-	butler_mixdown_buffer = new Sample[AudioDiskstream::disk_io_frames()];
-	butler_gain_buffer = new gain_t[AudioDiskstream::disk_io_frames()];
-	// this buffer is used for temp conversion purposes in filesources
-	char * conv_buffer = conversion_buffer(ButlerContext);
-	
 	while (true) {
 		pfd[0].fd = butler_request_pipe[0];
 		pfd[0].events = POLLIN|POLLERR|POLLHUP;
@@ -256,16 +251,15 @@ Session::butler_thread_work ()
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		
 		for (i = diskstreams.begin(); !transport_work_requested() && butler_should_run && i != diskstreams.end(); ++i) {
-			// cerr << "rah fondr " << (*i)->io()->name () << endl;
-			AudioDiskstream* ads = dynamic_cast<AudioDiskstream*>(*i);
-			if (!ads) continue; // FIXME
 
-			switch (ads->do_refill (butler_mixdown_buffer, butler_gain_buffer, conv_buffer)) {
+			Diskstream* const ds = *i;
+
+			switch (ds->do_refill ()) {
 			case 0:
-				bytes += ads->read_data_count();
+				bytes += ds->read_data_count();
 				break;
 			case 1:
-				bytes += ads->read_data_count();
+				bytes += ds->read_data_count();
 				disk_work_outstanding = true;
 				break;
 				
@@ -302,7 +296,7 @@ Session::butler_thread_work ()
 		for (i = diskstreams.begin(); !transport_work_requested() && butler_should_run && i != diskstreams.end(); ++i) {
 			// cerr << "write behind for " << (*i)->name () << endl;
 			
-			switch ((*i)->do_flush (conv_buffer)) {
+			switch ((*i)->do_flush (Session::ButlerContext)) {
 			case 0:
 				bytes += (*i)->write_data_count();
 				break;
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 73ba391873..0809aae6eb 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -196,7 +196,8 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	/* allocate conversion buffers */
 	_conversion_buffers[ButlerContext] = new char[AudioDiskstream::disk_io_frames() * 4];
 	_conversion_buffers[TransportContext] = new char[AudioDiskstream::disk_io_frames() * 4];
-	
+	AudioDiskstream::allocate_working_buffers();
+
 	/* default short fade = 15ms */
 
 	Crossfade::set_short_xfade_length ((jack_nframes_t) floor ((15.0 * frame_rate()) / 1000.0));