De-template-ification of port types (req. for LV2 MIDI, but nice code size reduction).

LV2 MIDI patching support (LV2 style MIDI throughout, inc. internal plugins).


git-svn-id: http://svn.drobilla.net/lad/ingen@415 a436a847-0d15-0410-975c-d299462d15a1

3 files changed, 189 insertions, 25 deletions

diff --git a/src/common/lv2ext/Makefile.am b/src/common/lv2ext/Makefile.am
index f346ae0f..6d6ebb6e 100644
--- a/src/common/lv2ext/Makefile.am
+++ b/src/common/lv2ext/Makefile.am
@@ -1 +1 @@
-noinst_HEADERS = lv2-miditype.h
+noinst_HEADERS = lv2-miditype.h lv2-midifunctions.h
diff --git a/src/common/lv2ext/lv2-midifunctions.h b/src/common/lv2ext/lv2-midifunctions.h
new file mode 100644
index 00000000..2334eff3
--- /dev/null
+++ b/src/common/lv2ext/lv2-midifunctions.h
@@ -0,0 +1,162 @@
+/****************************************************************************
+    
+    lv2-midifunctions.h - support 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_MIDIFUNCTIONS
+#define LV2_MIDIFUNCTIONS
+
+#include <string.h>
+#include <stdlib.h>
+
+#include "lv2-miditype.h"
+
+
+/** This structure contains information about a MIDI port buffer, the 
+    current period size, and the position in the MIDI data buffer that
+    we are currently reading from or writing to. It needs to be recreated
+    or at least reinitialised every process() call. */
+typedef struct {
+
+  /** The MIDI port structure that we want to read or write. */
+  LV2_MIDI* midi;
+  
+  /** The number of frames in this process cycle. */
+  uint32_t frame_count;
+  
+  /** The current position in the data buffer. Should be initialised to 0. */
+  uint32_t position;
+
+} LV2_MIDIState;
+
+
+static LV2_MIDI* lv2midi_new(uint32_t capacity)
+{
+	LV2_MIDI* midi = (LV2_MIDI*)malloc(sizeof(LV2_MIDI));
+
+	midi->event_count = 0;
+	midi->capacity = capacity;
+	midi->size = 0;
+	midi->data = (unsigned char*)malloc(sizeof(unsigned char) * capacity);
+
+	return midi;
+}
+
+
+static void lv2midi_free(LV2_MIDI* midi)
+{
+	free(midi->data);
+	free(midi);
+}
+
+
+static void lv2midi_reset_buffer(LV2_MIDI* midi)
+{
+	midi->event_count = 0;
+	midi->size = 0;
+}
+
+static void lv2midi_reset_state(LV2_MIDIState* state, LV2_MIDI* midi, uint32_t frame_count)
+{
+	state->midi = midi;
+	state->frame_count = frame_count;
+	state->position = 0;
+}
+
+
+/** 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.
+    It does not advance the read position in the MIDI data buffer, two 
+    subsequent calls to lv2midi_get_event() will read the same event.
+    
+    The function returns the timestamp for the read event, or the @c frame_count
+    member of @c state if there are no more events in the buffer. */
+static double lv2midi_get_event(LV2_MIDIState* state,
+                                double* timestamp, 
+                                uint32_t* size, 
+                                unsigned char** data) {
+  
+  if (state->position >= state->midi->size) {
+    state->position = state->midi->size;
+    *timestamp = state->frame_count;
+    *size = 0;
+    *data = NULL;
+    return *timestamp;
+  }
+  
+  *timestamp = *(double*)(state->midi->data + state->position);
+  *size = *(size_t*)(state->midi->data + state->position + sizeof(double));
+  *data = state->midi->data + state->position + 
+    sizeof(double) + sizeof(size_t);
+  return *timestamp;
+}
+
+
+/** 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
+    is advanced automatically. */
+static int lv2midi_put_event(LV2_MIDIState* state, 
+                             double timestamp,
+                             uint32_t size,
+                             const unsigned char* data) {
+
+  if (state->midi->capacity - state->midi->size < 
+      sizeof(double) + sizeof(size_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);
+  state->midi->size += size;
+  
+  ++state->midi->event_count;
+  
+  return 0;
+}
+
+
+#endif
+
diff --git a/src/common/lv2ext/lv2-miditype.h b/src/common/lv2ext/lv2-miditype.h
index 332e57f1..5350e4f7 100644
--- a/src/common/lv2ext/lv2-miditype.h
+++ b/src/common/lv2ext/lv2-miditype.h
@@ -1,37 +1,38 @@
-/************************************************************************
-
-   LV2 MIDI Data Type Extension
-   Copyright 2006 Lars Luthman in 2006
-
-   This library 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 2.1 of
-   the License, or (at your option) any later version.
-   
-   This library 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 library; if not, write to the Free Software
-   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
-   USA.
+/****************************************************************************
+    
+    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/namespace#miditype> should be a pointer 
+    <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):
+    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;
@@ -71,7 +72,8 @@
         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);
+        do_something_with_event(timestamp, size, 
+                                midi_data->data + buffer_offset);
         buffer_offset += size;
       }