Move MidiRingBuffer::read into .cc file to avoid the 2 hour dev cycle (no functional changes).

git-svn-id: svn://localhost/ardour2/branches/3.0@4352 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 126 insertions, 0 deletions

diff --git a/libs/ardour/midi_ring_buffer.cc b/libs/ardour/midi_ring_buffer.cc
new file mode 100644
index 0000000000..151da803cb
--- /dev/null
+++ b/libs/ardour/midi_ring_buffer.cc
@@ -0,0 +1,126 @@
+/*
+    Copyright (C) 2006-2008 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
+    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., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "ardour/midi_ring_buffer.h"
+#include "ardour/midi_buffer.h"
+#include "ardour/event_type_map.h"
+
+namespace ARDOUR {
+
+/** Read a block of MIDI events from buffer.
+ *
+ * Timestamps of events returned are relative to start (i.e. event with stamp 0
+ * occurred at start), with offset added.
+ */
+size_t
+MidiRingBuffer::read(MidiBuffer& dst, nframes_t start, nframes_t end, nframes_t offset)
+{
+	if (read_space() == 0) {
+		//std::cerr << "MRB: NO READ SPACE" << std::endl;
+		return 0;
+	}
+
+	Evoral::EventTime ev_time;
+	Evoral::EventType ev_type;
+	uint32_t          ev_size;
+
+	size_t count = 0;
+
+	//std::cerr << "MRB read " << start << " .. " << end << " + " << offset << std::endl;
+
+	while (read_space() >= sizeof(Evoral::EventTime) + sizeof(Evoral::EventType) + sizeof(uint32_t)) {
+
+		full_peek(sizeof(Evoral::EventTime), (uint8_t*)&ev_time);
+
+		if (ev_time > end) {
+			//std::cerr << "MRB: PAST END (" << ev_time << " : " << end << ")" << std::endl;
+			break;
+		} else if (ev_time < start) {
+			//std::cerr << "MRB (start " << start << ") - Skipping event at (too early) time " << ev_time << std::endl;
+			break;
+		}
+
+		bool success = read_prefix(&ev_time, &ev_type, &ev_size);
+		if (!success) {
+			std::cerr << "WARNING: error reading event prefix from MIDI ring" << std::endl;
+			continue;
+		}
+
+		// This event marks a loop happening. this means that
+		// the next events timestamp will be non-monotonic.
+		if (ev_type == LoopEventType) {
+			ev_time -= start;
+			ev_time += offset;
+			Evoral::MIDIEvent loopevent(LoopEventType, ev_time); 
+			dst.push_back(loopevent);
+
+			
+			// We can safely return, without reading the data, because
+			// a LoopEvent does not have data.
+			return count + 1;
+		}
+
+		uint8_t status;
+		success = full_peek(sizeof(uint8_t), &status);
+		assert(success); // If this failed, buffer is corrupt, all hope is lost
+
+		// Ignore event if it doesn't match channel filter
+		if (is_channel_event(status) && get_channel_mode() == FilterChannels) {
+			const uint8_t channel = status & 0x0F;
+			if ( !(get_channel_mask() & (1L << channel)) ) {
+				//std::cerr << "MRB skipping event due to channel mask" << std::endl;
+				skip(ev_size); // Advance read pointer to next event
+				continue;
+			}
+		}
+
+		//std::cerr << "MRB " << this << " - Reading event, time = "
+		//	<< ev_time << " - " << start << " => " << ev_time - start
+		//	<< ", size = " << ev_size << std::endl;
+
+		assert(ev_time >= start);
+		ev_time -= start;
+		ev_time += offset;
+
+		uint8_t* write_loc = dst.reserve(ev_time, ev_size);
+		if (write_loc == NULL) {
+			//std::cerr << "MRB: Unable to reserve space in buffer, event skipped";
+			continue;
+		}
+
+		success = Evoral::EventRingBuffer::full_read(ev_size, write_loc);
+
+		if (success) {
+			if (is_channel_event(status) && get_channel_mode() == ForceChannel) {
+				write_loc[0] = (write_loc[0] & 0xF0) | (get_channel_mask() & 0x0F);
+			}
+			++count;
+			//std::cerr << "MRB - read event at time " << ev_time << std::endl;
+		} else {
+			std::cerr << "WARNING: error reading event contents from MIDI ring" << std::endl;
+		}
+	}
+	
+	//std::cerr << "MTB read space: " << read_space() << std::endl;
+
+	return count;
+}
+
+
+} // namespace ARDOUR
+