LV2 MIDI fixes.

git-svn-id: http://svn.drobilla.net/lad/ingen@417 a436a847-0d15-0410-975c-d299462d15a1

3 files changed, 37 insertions, 202 deletions

diff --git a/src/common/lv2ext/Makefile.am b/src/common/lv2ext/Makefile.am
index 6d6ebb6e..ed382ecc 100644
--- a/src/common/lv2ext/Makefile.am
+++ b/src/common/lv2ext/Makefile.am
@@ -1 +1 @@
-noinst_HEADERS = lv2-miditype.h lv2-midifunctions.h
+noinst_HEADERS = lv2-midiport.h lv2-midifunctions.h
diff --git a/src/common/lv2ext/lv2-midifunctions.h b/src/common/lv2ext/lv2-midifunctions.h
index 2334eff3..0d309853 100644
--- a/src/common/lv2ext/lv2-midifunctions.h
+++ b/src/common/lv2ext/lv2-midifunctions.h
@@ -2,7 +2,7 @@
     
     lv2-midifunctions.h - support file for using MIDI in LV2 plugins
     
-    Copyright (C) 2006  Lars Luthman <lars.luthman@gmail.com>
+    Copyright (C) 2006-2007  Lars Luthman <lars.luthman@gmail.com>
     
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU Lesser General Public License as published by
@@ -20,13 +20,18 @@
 
 ****************************************************************************/
 
+/** @file
+    This file contains static helper functions for the LV2 MIDI datatype
+    extension. 
+*/
+
 #ifndef LV2_MIDIFUNCTIONS
 #define LV2_MIDIFUNCTIONS
 
 #include <string.h>
 #include <stdlib.h>
 
-#include "lv2-miditype.h"
+#include "lv2-midiport.h"
 
 
 /** This structure contains information about a MIDI port buffer, the 
@@ -73,6 +78,7 @@ static void lv2midi_reset_buffer(LV2_MIDI* midi)
 	midi->size = 0;
 }
 
+
 static void lv2midi_reset_state(LV2_MIDIState* state, LV2_MIDI* midi, uint32_t frame_count)
 {
 	state->midi = midi;
@@ -81,28 +87,6 @@ static void lv2midi_reset_state(LV2_MIDIState* state, LV2_MIDI* midi, uint32_t f
 }
 
 
-/** This function advances the read/write position in @c state to the next 
-    event and returns its timestamp, or the @c frame_count member of @c state
-    is there are no more events. */
-static double lv2midi_increment(LV2_MIDIState* state) {
-
-  if (state->position + sizeof(double) + sizeof(size_t) >= state->midi->size) {
-    state->position = state->midi->size;
-    return state->frame_count;
-  }
-  
-  state->position += sizeof(double);
-  size_t size = *(size_t*)(state->midi->data + state->position);
-  state->position += sizeof(size_t);
-  state->position += size;
-  
-  if (state->position >= state->midi->size)
-    return state->frame_count;
-  
-  return *(double*)(state->midi->data + state->position);
-}
-
-
 /** This function reads one event from the port associated with the @c state
     parameter and writes its timestamp, size and a pointer to its data bytes
     into the parameters @c timestamp, @c size and @c data, respectively.
@@ -125,13 +109,35 @@ static double lv2midi_get_event(LV2_MIDIState* state,
   }
   
   *timestamp = *(double*)(state->midi->data + state->position);
-  *size = *(size_t*)(state->midi->data + state->position + sizeof(double));
+  *size = *(uint32_t*)(state->midi->data + state->position + sizeof(double));
   *data = state->midi->data + state->position + 
-    sizeof(double) + sizeof(size_t);
+    sizeof(double) + sizeof(uint32_t);
   return *timestamp;
 }
 
 
+/** This function advances the read/write position in @c state to the next 
+    event and returns its timestamp, or the @c frame_count member of @c state
+    is there are no more events. */
+static double lv2midi_step(LV2_MIDIState* state) {
+
+  if (state->position + sizeof(double) + sizeof(uint32_t) >= state->midi->size) {
+    state->position = state->midi->size;
+    return state->frame_count;
+  }
+  
+  state->position += sizeof(double);
+  uint32_t size = *(uint32_t*)(state->midi->data + state->position);
+  state->position += sizeof(uint32_t);
+  state->position += size;
+  
+  if (state->position >= state->midi->size)
+    return state->frame_count;
+  
+  return *(double*)(state->midi->data + state->position);
+}
+
+
 /** This function writes one MIDI event to the port buffer associated with
     @c state. It returns 0 when the event was written successfully to the
     buffer, and -1 when there was not enough room. The read/write position
@@ -142,14 +148,14 @@ static int lv2midi_put_event(LV2_MIDIState* state,
                              const unsigned char* data) {
 
   if (state->midi->capacity - state->midi->size < 
-      sizeof(double) + sizeof(size_t) + size)
+      sizeof(double) + sizeof(uint32_t) + size)
     return -1;
   
   *(double*)(state->midi->data + state->midi->size) = timestamp;
   state->midi->size += sizeof(double);
-  *(size_t*)(state->midi->data + state->midi->size) = size;
-  state->midi->size += sizeof(size_t);
-  memcpy(state->midi->data + state->midi->size, data, (size_t)size);
+  *(uint32_t*)(state->midi->data + state->midi->size) = size;
+  state->midi->size += sizeof(uint32_t);
+  memcpy(state->midi->data + state->midi->size, data, size);
   state->midi->size += size;
   
   ++state->midi->event_count;
diff --git a/src/common/lv2ext/lv2-miditype.h b/src/common/lv2ext/lv2-miditype.h
deleted file mode 100644
index 5350e4f7..00000000
--- a/src/common/lv2ext/lv2-miditype.h
+++ /dev/null
@@ -1,171 +0,0 @@
-/****************************************************************************
-    
-    lv2-miditype.h - header file for using MIDI in LV2 plugins
-    
-    Copyright (C) 2006  Lars Luthman <lars.luthman@gmail.com>
-    
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
-    
-    You should have received a copy of the GNU Lesser General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 01222-1307  USA
-
-****************************************************************************/
-
-#ifndef LV2_MIDITYPE_H
-#define LV2_MIDITYPE_H
-
-#include <stdint.h>
-
-/** This data structure is used to contain the MIDI events for one run() 
-    cycle. The port buffer for a LV2 port that has the datatype 
-    <http://ll-plugins.nongnu.org/lv2/ext/miditype> should be a pointer 
-    to an instance of this struct. 
-
-    To store two Note On events on MIDI channel 0 in a buffer, with timestamps
-    12 and 35.5, you could use something like this code (assuming that 
-    midi_data is a variable of type LV2_MIDI):
-    @code
-    
-      size_t buffer_offset = 0;
-      *(double*)(midi_data->data + buffer_offset) = 12;
-      buffer_offset += sizeof(double);
-      *(size_t*)(midi_data->data + buffer_offset) = 3;
-      buffer_offset += sizeof(size_t);
-      midi_data->data[buffer_offset++] = 0x90;
-      midi_data->data[buffer_offset++] = 0x48;
-      midi_data->data[buffer_offset++] = 0x64;
-      ++midi_data->event_count;
-      
-      *(double*)(midi_data->data + buffer_offset) = 35.5;
-      buffer_offset += sizeof(double);
-      *(size_t*)(midi_data->data + buffer_offset) = 3;
-      buffer_offset += sizeof(size_t);
-      midi_data->data[buffer_offset++] = 0x90;
-      midi_data->data[buffer_offset++] = 0x55;
-      midi_data->data[buffer_offset++] = 0x64;
-      ++midi_data->event_count;
-      
-      midi_data->size = buffer_offset;
-      
-    @endcode
-    
-    This would be done by the host in the case of an input port, and by the
-    plugin in the case of an output port. Whoever is writing events to the
-    buffer must also take care not to exceed the capacity of the data buffer.
-    
-    To read events from a buffer, you could do something like this:
-    @code
-    
-      size_t buffer_offset = 0;
-      uint32_t i;
-      for (i = 0; i < midi_data->event_count; ++i) {
-        double timestamp = *(double*)(midi_data->data + buffer_offset);
-        buffer_offset += sizeof(double);
-        size_t size = *(size_t*)(midi_data->data + buffer_offset);
-        buffer_offset += sizeof(size_t);
-        do_something_with_event(timestamp, size, 
-                                midi_data->data + buffer_offset);
-        buffer_offset += size;
-      }
-        
-    @endcode
-*/
-typedef struct {
-
-  /** The number of MIDI events in the data buffer. 
-      INPUT PORTS: It's the host's responsibility to set this field to the
-      number of MIDI events contained in the data buffer before calling the
-      plugin's run() function. The plugin may not change this field.
-      OUTPUT PORTS: It's the plugin's responsibility to set this field to the
-      number of MIDI events it has stored in the data buffer before returning
-      from the run() function. Any initial value should be ignored by the
-      plugin.
-  */
-  uint32_t  event_count;
-  
-  /** The size of the data buffer in bytes. It is set by the host and may not
-      be changed by the plugin. The host is allowed to change this between
-      run() calls.
-  */
-  uint32_t  capacity;
-  
-  /** The size of the initial part of the data buffer that actually contains
-      data.
-      INPUT PORTS: It's the host's responsibility to set this field to the
-      number of bytes used by all MIDI events it has written to the buffer
-      (including timestamps and size fields) before calling the plugin's 
-      run() function. The plugin may not change this field.
-      OUTPUT PORTS: It's the plugin's responsibility to set this field to
-      the number of bytes used by all MIDI events it has written to the
-      buffer (including timestamps and size fields) before returning from
-      the run() function. Any initial value should be ignored by the plugin.
-  */
-  uint32_t  size;
-  
-  /** The data buffer that is used to store MIDI events. The events are packed
-      after each other, and the format of each event is as follows:
-      
-      First there is a timestamp, which should have the type "double",
-      i.e. have the same bit size as a double and the same bit layout as a 
-      double (whatever that is on the current platform). This timestamp gives 
-      the offset from the beginning of the current cycle, in frames, that 
-      the MIDI event occurs on. It must be strictly smaller than the 'nframes'
-      parameter to the current run() call. The MIDI events in the buffer must 
-      be ordered by their timestamp, e.g. an event with a timestamp of 123.23
-      must be stored after an event with a timestamp of 65.0.
-      
-      The second part of the event is a size field, which should have the type
-      "size_t" (as defined in the standard C header stddef.h). It should 
-      contain the size of the MIDI data for this event, i.e. the number of 
-      bytes used to store the actual MIDI event. The bytes used by the 
-      timestamp and the size field should not be counted.
-      
-      The third part of the event is the actual MIDI data. There are some
-      requirements that must be followed:
-      
-      * Running status is not allowed. Every event must have its own status 
-        byte.
-      * Note On events with velocity 0 are not allowed. These events are 
-        equivalent to Note Off in standard MIDI streams, but in order to make
-        plugins and hosts easier to write, as well as more efficient, only
-        proper Note Off events are allowed as Note Off. 
-      * "Realtime events" (status bytes 0xF8 to 0xFF) are allowed, but may not
-        occur inside other events like they are allowed to in hardware MIDI 
-        streams.
-      * All events must be fully contained in a single data buffer, i.e. events
-        may not "wrap around" by storing the first few bytes in one buffer and
-        then wait for the next run() call to store the rest of the event. If 
-        there isn't enough space in the current data buffer to store an event,
-        the event will either have to wait until next run() call, be ignored,
-        or compensated for in some more clever way.
-      * All events must be valid MIDI events. This means for example that
-        only the first byte in each event (the status byte) may have the eighth
-        bit set, that Note On and Note Off events are always 3 bytes long etc.
-        The MIDI writer (host or plugin) is responsible for writing valid MIDI
-        events to the buffer, and the MIDI reader (plugin or host) can assume
-        that all events are valid.
-        
-      On a platform where double is 8 bytes and size_t is 4 bytes, the data 
-      buffer layout for a 3-byte event followed by a 4-byte event may look 
-      something like this:
-      _______________________________________________________________
-      | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ...
-      |TIMESTAMP 1    |SIZE 1 |DATA |TIMESTAMP 2    |SIZE 2 |DATA   | ...
-      
-  */
-  unsigned char* data;
-
-} LV2_MIDI;
-
-
-
-#endif