Rewrote MidiRingBuffer to more efficiently pack data (flat pack stamps, sizes, and event data into a single buffer).

Eliminate a double-copy on MIDI playback (MidiRingBuffer -> MidiBuffer).
Various MIDI diskstream/source/SMF fixes (only write when appropriate, handle transport locates, etc).
Fix MIDI rec region size/offset problems.
Code cleanups.


git-svn-id: svn://localhost/ardour2/trunk@1934 d708f5d6-7413-0410-9779-e7cbd77b26cf

7 files changed, 229 insertions, 143 deletions

diff --git a/libs/ardour/ardour/buffer.h b/libs/ardour/ardour/buffer.h
index b890afbb03..86a7aa9f95 100644
--- a/libs/ardour/ardour/buffer.h
+++ b/libs/ardour/ardour/buffer.h
@@ -197,18 +197,14 @@ public:
 	
 	void read_from(const Buffer& src, nframes_t nframes, nframes_t offset);
 
-	bool push_back(const MidiEvent& event);
+	bool  push_back(const MidiEvent& event);
+	Byte* reserve(nframes_t time, size_t size);
 	
 	const MidiEvent& operator[](size_t i) const { assert(i < _size); return _events[i]; }
 	MidiEvent& operator[](size_t i) { assert(i < _size); return _events[i]; }
 
 	static size_t max_event_size() { return MAX_EVENT_SIZE; }
 
-	//void set_size(size_t size) { _size = size; }
-
-	//const RawMidi* data() const { return _data; }
-	//RawMidi*       data()       { return _data; }
-
 private:
 	// These are undefined (prevent copies)
 	MidiBuffer(const MidiBuffer& copy);            
@@ -221,8 +217,8 @@ private:
 	 * (_size * MAX_EVENT_SIZE)
 	 */
 
-	MidiEvent* _events;     ///< Event structs that point to offsets in _data
-	RawMidi*   _data;       ///< MIDI, straight up.  No time stamps.
+	MidiEvent* _events; ///< Event structs that point to offsets in _data
+	Byte*      _data;   ///< MIDI, straight up.  No time stamps.
 };
 
 } // namespace ARDOUR
diff --git a/libs/ardour/ardour/midi_diskstream.h b/libs/ardour/ardour/midi_diskstream.h
index bc126ce364..cf78d0d05b 100644
--- a/libs/ardour/ardour/midi_diskstream.h
+++ b/libs/ardour/ardour/midi_diskstream.h
@@ -145,19 +145,12 @@ class MidiDiskstream : public Diskstream
 	void engage_record_enable ();
 	void disengage_record_enable ();
 	
-	// FIXME: This is basically a single ChannelInfo.. abstractify that concept?
-	MidiRingBuffer*                    _playback_buf;
-	MidiRingBuffer*                    _capture_buf;
-	//RawMidi*                          _current_playback_buffer;
-	//RawMidi*                          _current_capture_buffer;
-	//RawMidi*                          _playback_wrap_buffer;
-	//RawMidi*                          _capture_wrap_buffer;
+	MidiRingBuffer*                   _playback_buf;
+	MidiRingBuffer*                   _capture_buf;
 	MidiPort*                         _source_port;
 	boost::shared_ptr<SMFSource>      _write_source;
 	RingBufferNPT<CaptureTransition>* _capture_transition_buf;
-	//RingBufferNPT<RawMidi>::rw_vector _playback_vector;
-	//RingBufferNPT<RawMidi>::rw_vector _capture_vector;
-	nframes_t _last_flush_frame;
+	nframes_t                         _last_flush_frame;
 };
 
 }; /* namespace ARDOUR */
diff --git a/libs/ardour/ardour/midi_ring_buffer.h b/libs/ardour/ardour/midi_ring_buffer.h
index 71f42d7182..86319ad4b2 100644
--- a/libs/ardour/ardour/midi_ring_buffer.h
+++ b/libs/ardour/ardour/midi_ring_buffer.h
@@ -21,61 +21,67 @@
 
 #include <algorithm>
 #include <ardour/types.h>
-#include <pbd/ringbufferNPT.h>
 #include <ardour/buffer.h>
 
 namespace ARDOUR {
 
-/** A MIDI RingBuffer
- * (necessary because MIDI events are variable sized so a generic RB won't do).
+
+/** A RingBuffer.
+ * Read/Write realtime safe.
+ * Single-reader Single-writer thread safe.
+ *
+ * This is Raul::RingBuffer, lifted for MIDIRingBuffer to inherit from as it works
+ * a bit differently than PBD::Ringbuffer.  This could/should be replaced with
+ * the PBD ringbuffer to decrease code size, but this code is tested and known to
+ * work, so here it sits for now...
  *
- * ALL publically accessible sizes refer to event COUNTS.  What actually goes
- * on in here is none of the callers business :)
+ * Ignore this class, use MidiRingBuffer.
  */
-class MidiRingBuffer {
+template <typename T>
+class MidiRingBufferBase {
 public:
-	MidiRingBuffer (size_t size)
+
+	/** @param size Size in bytes.
+	 */
+	MidiRingBufferBase(size_t size)
 		: _size(size)
-		, _max_event_size(MidiBuffer::max_event_size())
-		, _ev_buf(new MidiEvent[size])
-		, _raw_buf(new RawMidi[size * _max_event_size])
+		, _buf(new T[size])
 	{
-		reset ();
+		reset();
 		assert(read_space() == 0);
 		assert(write_space() == size - 1);
 	}
 	
-	virtual ~MidiRingBuffer() {
-		delete[] _ev_buf;
-		delete[] _raw_buf;
+	virtual ~MidiRingBufferBase() {
+		delete[] _buf;
 	}
 
-	void reset () {
-		/* !!! NOT THREAD SAFE !!! */
-		g_atomic_int_set (&_write_ptr, 0);
-		g_atomic_int_set (&_read_ptr, 0);
+	/** Reset(empty) the ringbuffer.
+	 * NOT thread safe.
+	 */
+	void reset() {
+		g_atomic_int_set(&_write_ptr, 0);
+		g_atomic_int_set(&_read_ptr, 0);
 	}
 
-	size_t write_space () {
-		size_t w, r;
+	size_t write_space() const {
 		
-		w = g_atomic_int_get (&_write_ptr);
-		r = g_atomic_int_get (&_read_ptr);
+		const size_t w = g_atomic_int_get(&_write_ptr);
+		const size_t r = g_atomic_int_get(&_read_ptr);
 		
 		if (w > r) {
 			return ((r - w + _size) % _size) - 1;
-		} else if (w < r) {
+		} else if(w < r) {
 			return (r - w) - 1;
 		} else {
 			return _size - 1;
 		}
 	}
 	
-	size_t read_space () {
-		size_t w, r;
+	size_t read_space() const {
 		
-		w = g_atomic_int_get (&_write_ptr);
-		r = g_atomic_int_get (&_read_ptr);
+		const size_t w = g_atomic_int_get(&_write_ptr);
+		const size_t r = g_atomic_int_get(&_read_ptr);
 		
 		if (w > r) {
 			return w - r;
@@ -86,139 +92,229 @@ public:
 
 	size_t capacity() const { return _size; }
 
-	/** Read one event and appends it to @a out. */
-	//size_t read(MidiBuffer& out);
+	size_t peek(size_t size, T* dst);
+	bool   full_peek(size_t size, T* dst);
+
+	size_t read(size_t size, T* dst);
+	bool   full_read(size_t size, T* dst);
+	
+	void   write(size_t size, const T* src);
+
+protected:
+	mutable gint _write_ptr;
+	mutable gint _read_ptr;
+	
+	size_t _size; ///< Size (capacity) in bytes
+	T*  _buf;  ///< size, event, size, event...
+};
 
-	/** Write one event (@a in) */
-	size_t write(const MidiEvent& in); // deep copies in
 
-	/** Read events all events up to time @a end into @a out, leaving stamps intact.
-	 * Any events before @a start will be dropped. */
-	size_t read(MidiBuffer& out, nframes_t start, nframes_t end);
+/** Peek at the ringbuffer (read w/o advancing read pointer).
+ *
+ * Note that a full read may not be done if the data wraps around.
+ * Caller must check return value and call again if necessary, or use the 
+ * full_peek method which does this automatically.
+ */
+template<typename T>
+size_t
+MidiRingBufferBase<T>::peek(size_t size, T* dst)
+{
+	const size_t priv_read_ptr = g_atomic_int_get(&_read_ptr);
 
-	/** Write all events from @a in, applying @a offset to all time stamps */
-	size_t write(const MidiBuffer& in, nframes_t offset = 0);
+	const size_t read_size = (priv_read_ptr + size < _size)
+			? size
+			: _size - priv_read_ptr;
+	
+	memcpy(dst, &_buf[priv_read_ptr], read_size);
+        
+	return read_size;
+}
 
-	inline void clear_event(size_t index);
 
-private:
+template<typename T>
+bool
+MidiRingBufferBase<T>::full_peek(size_t size, T* dst)
+{
+	if (read_space() < size)
+		return false;
 
-	// _event_ indices
-	mutable gint _write_ptr;
-	mutable gint _read_ptr;
+	const size_t read_size = peek(size, dst);
 	
-	size_t     _size;           // size (capacity) in events
-	size_t     _max_event_size; // ratio of raw_buf size to ev_buf size
-	MidiEvent* _ev_buf;         // these point into...
-	RawMidi*   _raw_buf;        // this
+	if (read_size < size)
+		peek(size - read_size, dst + read_size);
 
-};
+	return true;
+}
 
-/** Just for sanity checking */
-inline void
-MidiRingBuffer::clear_event(size_t index)
+
+/** Read from the ringbuffer.
+ *
+ * Note that a full read may not be done if the data wraps around.
+ * Caller must check return value and call again if necessary, or use the 
+ * full_read method which does this automatically.
+ */
+template<typename T>
+size_t
+MidiRingBufferBase<T>::read(size_t size, T* dst)
 {
-	memset(&_ev_buf[index].buffer, 0, _max_event_size);
-	_ev_buf[index].time = 0;
-	_ev_buf[index].size = 0;
-	_ev_buf[index].buffer = 0;
+	const size_t priv_read_ptr = g_atomic_int_get(&_read_ptr);
+
+	const size_t read_size = (priv_read_ptr + size < _size)
+			? size
+			: _size - priv_read_ptr;
+	
+	memcpy(dst, &_buf[priv_read_ptr], read_size);
+        
+	g_atomic_int_set(&_read_ptr, (priv_read_ptr + read_size) % _size);
 
+	return read_size;
 }
 
-inline size_t
-MidiRingBuffer::write (const MidiEvent& ev)
+
+template<typename T>
+bool
+MidiRingBufferBase<T>::full_read(size_t size, T* dst)
 {
-	//static nframes_t last_write_time = 0;
+	if (read_space() < size)
+		return false;
+
+	const size_t read_size = read(size, dst);
 	
-	assert(ev.size > 0);
+	if (read_size < size)
+		read(size - read_size, dst + read_size);
 
-	size_t priv_write_ptr = g_atomic_int_get(&_write_ptr);
+	return true;
+}
 
-	if (write_space () == 0) {
-		return 0;
+
+template<typename T>
+inline void
+MidiRingBufferBase<T>::write(size_t size, const T* src)
+{
+	const size_t priv_write_ptr = g_atomic_int_get(&_write_ptr);
+	
+	if (priv_write_ptr + size <= _size) {
+		memcpy(&_buf[priv_write_ptr], src, size);
+        g_atomic_int_set(&_write_ptr, (priv_write_ptr + size) % _size);
 	} else {
-		//assert(ev.time >= last_write_time);
+		const size_t this_size = _size - priv_write_ptr;
+		assert(this_size < size);
+		assert(priv_write_ptr + this_size <= _size);
+		memcpy(&_buf[priv_write_ptr], src, this_size);
+		memcpy(&_buf[0], src+this_size, size - this_size);
+        g_atomic_int_set(&_write_ptr, size - this_size);
+	}
+}
 
-		const size_t raw_index = priv_write_ptr * _max_event_size;
 
-		MidiEvent* const write_ev = &_ev_buf[priv_write_ptr];
-		*write_ev = ev;
+/* ******************************************************************** */
+	
+
+/** A MIDI RingBuffer.
+ *
+ * This is timestamps and MIDI packed sequentially into a single buffer, similarly
+ * to LV2 MIDI.  The buffer looks like this:
+ *
+ * [timestamp][size][size bytes of raw MIDI][timestamp][size][etc..]
+ */
+class MidiRingBuffer : public MidiRingBufferBase<Byte> {
+public:
+
+	/** @param size Size in bytes.
+	 */
+	MidiRingBuffer(size_t size)
+		: MidiRingBufferBase<Byte>(size)
+	{}
+
+	size_t write(nframes_t time, size_t size, const Byte* buf);
+	bool   read(nframes_t time, size_t* size, Byte* buf);
+
+	size_t read(MidiBuffer& dst, nframes_t start, nframes_t end);
+};
 
-		memcpy(&_raw_buf[raw_index], ev.buffer, ev.size);
-		write_ev->buffer = &_raw_buf[raw_index];
-        g_atomic_int_set(&_write_ptr, (priv_write_ptr + 1) % _size);
-		
-		//printf("MRB - wrote %xd %d %d with time %u at index %zu (raw index %zu)\n",
-		//	write_ev->buffer[0], write_ev->buffer[1], write_ev->buffer[2], write_ev->time,
-		//	priv_write_ptr, raw_index);
-		
-		assert(write_ev->size = ev.size);
 
-		//last_write_time = ev.time;
-		//printf("(W) read space: %zu\n", read_space());
+inline bool
+MidiRingBuffer::read(nframes_t time, size_t* size, Byte* buf)
+{
+	bool success = MidiRingBufferBase<Byte>::full_read(sizeof(nframes_t), (Byte*)time);
+	if (success)
+		success = MidiRingBufferBase<Byte>::full_read(sizeof(size_t), (Byte*)size);
+	if (success)
+		success = MidiRingBufferBase<Byte>::full_read(*size, buf);
+
+	return success;
+}
+
+
+inline size_t
+MidiRingBuffer::write(nframes_t time, size_t size, const Byte* buf)
+{
+	assert(size > 0);
 
-		return 1;
+	if (write_space() < (sizeof(nframes_t) + sizeof(size_t) + size)) {
+		return 0;
+	} else {
+		MidiRingBufferBase<Byte>::write(sizeof(nframes_t), (Byte*)&time);
+		MidiRingBufferBase<Byte>::write(sizeof(size_t), (Byte*)&size);
+		MidiRingBufferBase<Byte>::write(size, buf);
+		return size;
 	}
 }
 
+
 inline size_t
 MidiRingBuffer::read(MidiBuffer& dst, nframes_t start, nframes_t end)
 {
 	if (read_space() == 0)
 		return 0;
 
-	size_t         priv_read_ptr = g_atomic_int_get(&_read_ptr);
-	nframes_t time          = _ev_buf[priv_read_ptr].time;
-	size_t         count         = 0;
-	size_t         limit         = read_space();
+	MidiEvent ev;
 
-	while (time <= end && limit > 0) {
-		MidiEvent* const read_ev = &_ev_buf[priv_read_ptr];
-		if (time >= start) {
-			dst.push_back(*read_ev);
+	size_t count = 0;
+
+	while (read_space() > sizeof(nframes_t) + sizeof(size_t)) {
+	
+		full_peek(sizeof(nframes_t), (Byte*)&ev.time);
+	
+		if (ev.time > end)
+			break;
+
+		bool success = MidiRingBufferBase<Byte>::full_read(sizeof(nframes_t), (Byte*)&ev.time);
+		if (success)
+			success = MidiRingBufferBase<Byte>::full_read(sizeof(size_t), (Byte*)&ev.size);
+		
+		if (!success) {
+			cerr << "MRB: READ ERROR (time/size)" << endl;
+			continue;
+		}
+
+		if (ev.time >= start) {
+			Byte* write_loc = dst.reserve(ev.time, ev.size);
+			success = MidiRingBufferBase<Byte>::full_read(ev.size, write_loc);
+		
+			if (!success)
+				cerr << "MRB: READ ERROR (data)" << endl;
+			
 			//printf("MRB - read %#X %d %d with time %u at index %zu\n",
-			//	read_ev->buffer[0], read_ev->buffer[1], read_ev->buffer[2], read_ev->time,
+			//	ev.buffer[0], ev.buffer[1], ev.buffer[2], ev.time,
 			//	priv_read_ptr);
+			//
 		} else {
-			printf("MRB - SKIPPING - %#X %d %d with time %u at index %zu\n",
-				read_ev->buffer[0], read_ev->buffer[1], read_ev->buffer[2], read_ev->time,
-				priv_read_ptr);
+			printf("MRB - SKIPPING - %#X %d %d with time %u\n",
+					ev.buffer[0], ev.buffer[1], ev.buffer[2], ev.time);
 			break;
 		}
 
-		clear_event(priv_read_ptr);
-
 		++count;
-		--limit;
-		
-		priv_read_ptr = (priv_read_ptr + 1) % _size;
-		
-		assert(read_ev->time <= end);
-		time = _ev_buf[priv_read_ptr].time;
+
+		assert(ev.time <= end);
 	}
 	
-	g_atomic_int_set(&_read_ptr, priv_read_ptr);
-	
 	//printf("(R) read space: %zu\n", read_space());
 
 	return count;
 }
 
-inline size_t
-MidiRingBuffer::write(const MidiBuffer& in, nframes_t offset)
-{
-	size_t num_events = in.size();
-	size_t to_write = std::min(write_space(), num_events);
-
-	// FIXME: double copy :/
-	for (size_t i=0; i < to_write; ++i) {
-		MidiEvent ev = in[i];
-		ev.time += offset;
-		write(ev);
-	}
-
-	return to_write;
-}
 
 } // namespace ARDOUR
 
diff --git a/libs/ardour/ardour/midi_source.h b/libs/ardour/ardour/midi_source.h
index 5504db6ab6..dec9536c74 100644
--- a/libs/ardour/ardour/midi_source.h
+++ b/libs/ardour/ardour/midi_source.h
@@ -30,6 +30,7 @@
 
 #include <ardour/source.h>
 #include <ardour/ardour.h>
+#include <ardour/buffer.h>
 #include <pbd/stateful.h>
 #include <pbd/xml++.h>
 
@@ -62,9 +63,7 @@ class MidiSource : public Source
 	static sigc::signal<void,MidiSource*> MidiSourceCreated;
 	       
 	// The MIDI equivalent to "peaks"
-	static int  start_view_data_thread ();
-	static void stop_view_data_thread ();
-	mutable sigc::signal<void,nframes_t,nframes_t> ViewDataRangeReady;
+	mutable sigc::signal<void,boost::shared_ptr<MidiBuffer>,nframes_t,nframes_t> ViewDataRangeReady;
 	
 	XMLNode& get_state ();
 	int set_state (const XMLNode&);
diff --git a/libs/ardour/ardour/smf_source.h b/libs/ardour/ardour/smf_source.h
index d422a8af9e..6ab81a2ac3 100644
--- a/libs/ardour/ardour/smf_source.h
+++ b/libs/ardour/ardour/smf_source.h
@@ -86,6 +86,8 @@ class SMFSource : public MidiSource {
 	XMLNode& get_state ();
 	int set_state (const XMLNode&);
 
+	void seek_to(nframes_t time);
+
   private:
 
 	int init (string idstr, bool must_exist);
@@ -96,9 +98,9 @@ class SMFSource : public MidiSource {
 	bool find (std::string path, bool must_exist, bool& is_new);
 	bool removable() const;
 	bool writable() const { return _flags & Writable; }
-	
+
 	int open();
-	
+
 	void     write_chunk_header(char id[4], uint32_t length);
 	void     write_chunk(char id[4], uint32_t length, void* data);
 	size_t   write_var_len(uint32_t val);
diff --git a/libs/ardour/ardour/source.h b/libs/ardour/ardour/source.h
index 807ea089e6..2a6e0c8638 100644
--- a/libs/ardour/ardour/source.h
+++ b/libs/ardour/ardour/source.h
@@ -76,18 +76,18 @@ class Source : public PBD::StatefulDestructible
   protected:
 	void update_length (nframes_t pos, nframes_t cnt);
 	
-	Session&          _session;
-	string            _name;
-	DataType          _type;
-	time_t            _timestamp;
-	nframes_t    _length;
+	Session&  _session;
+	string    _name;
+	DataType  _type;
+	time_t    _timestamp;
+	nframes_t _length;
 
 	Glib::Mutex playlist_lock;
 	typedef std::map<boost::shared_ptr<ARDOUR::Playlist>, uint32_t > PlaylistMap;
 	PlaylistMap _playlists;
 
   private:
-	uint32_t          _in_use;
+	uint32_t _in_use;
 };
 
 }
diff --git a/libs/ardour/ardour/types.h b/libs/ardour/ardour/types.h
index 766c3d4907..813c75f673 100644
--- a/libs/ardour/ardour/types.h
+++ b/libs/ardour/ardour/types.h
@@ -60,7 +60,7 @@ namespace ARDOUR {
 	typedef uint32_t                    nframes_t;
 
 	typedef jack_midi_event_t MidiEvent;
-	typedef unsigned char     RawMidi;
+	typedef unsigned char     Byte;
 
 	enum IOChange {
 		NoChange = 0,