Add lv2_atom_sequence_clear() and lv2_atom_sequence_append_event() helper functions.

Add MIDI fifths example plugin for simple non-forge MIDI reading and writing.

9 files changed, 415 insertions, 0 deletions

diff --git a/lv2/lv2plug.in/ns/ext/atom/lv2-atom.doap.ttl b/lv2/lv2plug.in/ns/ext/atom/lv2-atom.doap.ttl
index 251d998..f70a410 100644
--- a/lv2/lv2plug.in/ns/ext/atom/lv2-atom.doap.ttl
+++ b/lv2/lv2plug.in/ns/ext/atom/lv2-atom.doap.ttl
@@ -22,6 +22,8 @@
 				rdfs:label "Add lv2_atom_forge_is_object_type() and lv2_atom_forge_is_blank() to ease backwards compatibility."
 			] , [
 				rdfs:label "Add lv2_atom_forge_key() for terser object writing."
+			] , [
+				rdfs:label "Add lv2_atom_sequence_clear() and lv2_atom_sequence_append_event() helper functions."
 			]
 		]
 	] , [
diff --git a/lv2/lv2plug.in/ns/ext/atom/util.h b/lv2/lv2plug.in/ns/ext/atom/util.h
index d306e1c..d7c020b 100644
--- a/lv2/lv2plug.in/ns/ext/atom/util.h
+++ b/lv2/lv2plug.in/ns/ext/atom/util.h
@@ -129,6 +129,52 @@ lv2_atom_sequence_next(const LV2_Atom_Event* i)
 
 /**
    @}
+   @name Sequence Utilities
+   @{
+*/
+
+/**
+   Clear all events from @p sequence.
+
+   This simply resets the size field, the other fields are left untouched.
+*/
+static inline void
+lv2_atom_sequence_clear(LV2_Atom_Sequence* seq)
+{
+	seq->atom.size = sizeof(LV2_Atom_Sequence_Body);
+}
+
+/**
+   Append an event at the end of @p sequence.
+
+   @param seq Sequence to append to.
+   @param capacity Total capacity of the sequence atom
+   (e.g. as set by the host for sequence output ports).
+   @param event Event to write.
+
+   @return A pointer to the newly written event in @p seq,
+   or NULL on failure (insufficient space).
+*/
+static inline LV2_Atom_Event*
+lv2_atom_sequence_append_event(LV2_Atom_Sequence*    seq,
+                               uint32_t              capacity,
+                               const LV2_Atom_Event* event)
+{
+	const uint32_t total_size = (uint32_t)sizeof(*event) + event->body.size;
+	if (capacity - seq->atom.size < total_size) {
+		return NULL;
+	}
+
+	LV2_Atom_Event* e = lv2_atom_sequence_end(&seq->body, seq->atom.size);
+	memcpy(e, event, total_size);
+
+	seq->atom.size += lv2_atom_pad_size(total_size);
+
+	return e;
+}
+
+/**
+   @}
    @name Tuple Iterator
    @{
 */
diff --git a/plugins/eg06-fifths.lv2/README.txt b/plugins/eg06-fifths.lv2/README.txt
new file mode 100644
index 0000000..2154321
--- /dev/null
+++ b/plugins/eg06-fifths.lv2/README.txt
@@ -0,0 +1,3 @@
+== Fifths ==
+
+This plugin demonstrates simple MIDI event reading and writing.
diff --git a/plugins/eg06-fifths.lv2/fifths.c b/plugins/eg06-fifths.lv2/fifths.c
new file mode 100644
index 0000000..13d47f4
--- /dev/null
+++ b/plugins/eg06-fifths.lv2/fifths.c
@@ -0,0 +1,191 @@
+/*
+  LV2 Fifths Example Plugin
+  Copyright 2014 David Robillard <d@drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+#ifndef __cplusplus
+#    include <stdbool.h>
+#endif
+
+#include <sndfile.h>
+
+#include "lv2/lv2plug.in/ns/ext/atom/util.h"
+#include "lv2/lv2plug.in/ns/ext/midi/midi.h"
+#include "lv2/lv2plug.in/ns/ext/patch/patch.h"
+#include "lv2/lv2plug.in/ns/ext/state/state.h"
+#include "lv2/lv2plug.in/ns/ext/urid/urid.h"
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+
+#include "./uris.h"
+
+enum {
+	FIFTHS_IN  = 0,
+	FIFTHS_OUT = 1
+};
+
+typedef struct {
+	// Features
+	LV2_URID_Map* map;
+
+	// Ports
+	const LV2_Atom_Sequence* in_port;
+	LV2_Atom_Sequence*       out_port;
+
+	// URIs
+	FifthsURIs uris;
+} Fifths;
+
+static void
+connect_port(LV2_Handle instance,
+             uint32_t   port,
+             void*      data)
+{
+	Fifths* self = (Fifths*)instance;
+	switch (port) {
+	case FIFTHS_IN:
+		self->in_port = (const LV2_Atom_Sequence*)data;
+		break;
+	case FIFTHS_OUT:
+		self->out_port = (LV2_Atom_Sequence*)data;
+		break;
+	default:
+		break;
+	}
+}
+
+static LV2_Handle
+instantiate(const LV2_Descriptor*     descriptor,
+            double                    rate,
+            const char*               path,
+            const LV2_Feature* const* features)
+{
+	// Allocate and initialise instance structure.
+	Fifths* self = (Fifths*)malloc(sizeof(Fifths));
+	if (!self) {
+		return NULL;
+	}
+	memset(self, 0, sizeof(Fifths));
+
+	// Get host features
+	for (int i = 0; features[i]; ++i) {
+		if (!strcmp(features[i]->URI, LV2_URID__map)) {
+			self->map = (LV2_URID_Map*)features[i]->data;
+		}
+	}
+	if (!self->map) {
+		fprintf(stderr, "Missing feature urid:map\n");
+		free(self);
+		return NULL;
+	}
+
+	// Map URIs and initialise forge/logger
+	map_fifths_uris(self->map, &self->uris);
+ 
+	return (LV2_Handle)self;
+}
+
+static void
+cleanup(LV2_Handle instance)
+{
+	free(instance);
+}
+
+static void
+run(LV2_Handle instance,
+    uint32_t   sample_count)
+{
+	Fifths*     self = (Fifths*)instance;
+	FifthsURIs* uris = &self->uris;
+
+	// Struct for a 3 byte MIDI event, used for writing notes
+	typedef struct {
+		LV2_Atom_Event event;
+		uint8_t        msg[3];
+	} MIDINoteEvent;
+
+	// Initially self->out_port contains a Chunk with size set to capacity
+
+	// Get the capacity
+	const uint32_t out_capacity = self->out_port->atom.size;
+
+	// Write an empty Sequence header to the output
+	lv2_atom_sequence_clear(self->out_port);
+	self->out_port->atom.type = self->in_port->atom.type;
+
+	// Read incoming events
+	LV2_ATOM_SEQUENCE_FOREACH(self->in_port, ev) {
+		if (ev->body.type == uris->midi_Event) {
+			const uint8_t* const msg = (const uint8_t*)(ev + 1);
+			switch (lv2_midi_message_type(msg)) {
+			case LV2_MIDI_MSG_NOTE_ON:
+			case LV2_MIDI_MSG_NOTE_OFF:
+				// Forward note to output
+				lv2_atom_sequence_append_event(
+					self->out_port, out_capacity, ev);
+
+				const uint8_t note = msg[1];
+				if (note < 127 - 7) {
+					// Make a note one 5th (7 semitones) higher than input
+					MIDINoteEvent fifth;
+					fifth.event  = *ev;
+					fifth.msg[0] = msg[0];      // Same status
+					fifth.msg[1] = msg[1] + 7;  // Pitch up 7 semitones
+					fifth.msg[2] = msg[2];      // Same velocity
+
+					// Write 5th event
+					lv2_atom_sequence_append_event(
+						self->out_port, out_capacity, &fifth.event);
+				}
+				break;
+			default:
+				// Forward all other MIDI events directly
+				lv2_atom_sequence_append_event(
+					self->out_port, out_capacity, ev);
+				break;
+			}
+		}
+	}
+}
+
+static const void*
+extension_data(const char* uri)
+{
+	return NULL;
+}
+
+static const LV2_Descriptor descriptor = {
+	EG_FIFTHS_URI,
+	instantiate,
+	connect_port,
+	NULL,  // activate,
+	run,
+	NULL,  // deactivate,
+	cleanup,
+	extension_data
+};
+
+LV2_SYMBOL_EXPORT
+const LV2_Descriptor* lv2_descriptor(uint32_t index)
+{
+	switch (index) {
+	case 0:
+		return &descriptor;
+	default:
+		return NULL;
+	}
+}
diff --git a/plugins/eg06-fifths.lv2/fifths.ttl b/plugins/eg06-fifths.lv2/fifths.ttl
new file mode 100644
index 0000000..2d439c7
--- /dev/null
+++ b/plugins/eg06-fifths.lv2/fifths.ttl
@@ -0,0 +1,36 @@
+@prefix atom:  <http://lv2plug.in/ns/ext/atom#> .
+@prefix doap:  <http://usefulinc.com/ns/doap#> .
+@prefix lv2:   <http://lv2plug.in/ns/lv2core#> .
+@prefix patch: <http://lv2plug.in/ns/ext/patch#> .
+@prefix rdfs:  <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix state: <http://lv2plug.in/ns/ext/state#> .
+@prefix ui:    <http://lv2plug.in/ns/extensions/ui#> .
+@prefix urid:  <http://lv2plug.in/ns/ext/urid#> .
+@prefix work:  <http://lv2plug.in/ns/ext/worker#> .
+@prefix midi:  <http://lv2plug.in/ns/ext/midi#> .
+
+<http://lv2plug.in/plugins/eg-fifths>
+	a lv2:Plugin ;
+	doap:name "Example Fifths" ;
+	doap:license <http://opensource.org/licenses/isc> ;
+	lv2:project <http://lv2plug.in/ns/lv2> ;
+	lv2:requiredFeature urid:map ;
+	lv2:optionalFeature lv2:hardRTCapable ;
+	lv2:extensionData work:interface ;
+	lv2:port [
+		a lv2:InputPort ,
+			atom:AtomPort ;
+		atom:bufferType atom:Sequence ;
+		atom:supports midi:MidiEvent ;
+		lv2:index 0 ;
+		lv2:symbol "in" ;
+		lv2:name "In"
+	] , [
+		a lv2:OutputPort ,
+			atom:AtomPort ;
+		atom:bufferType atom:Sequence ;
+		atom:supports midi:MidiEvent ;
+		lv2:index 1 ;
+		lv2:symbol "out" ;
+		lv2:name "Out"
+	] .
diff --git a/plugins/eg06-fifths.lv2/manifest.ttl.in b/plugins/eg06-fifths.lv2/manifest.ttl.in
new file mode 100644
index 0000000..f87f2c1
--- /dev/null
+++ b/plugins/eg06-fifths.lv2/manifest.ttl.in
@@ -0,0 +1,8 @@
+@prefix lv2:  <http://lv2plug.in/ns/lv2core#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix ui:   <http://lv2plug.in/ns/extensions/ui#> .
+
+<http://lv2plug.in/plugins/eg-fifths>
+	a lv2:Plugin ;
+	lv2:binary <fifths@LIB_EXT@> ;
+	rdfs:seeAlso <fifths.ttl> .
diff --git a/plugins/eg06-fifths.lv2/uris.h b/plugins/eg06-fifths.lv2/uris.h
new file mode 100644
index 0000000..e174fb4
--- /dev/null
+++ b/plugins/eg06-fifths.lv2/uris.h
@@ -0,0 +1,64 @@
+/*
+  LV2 Fifths Example Plugin
+  Copyright 2014 David Robillard <d@drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef FIFTHS_URIS_H
+#define FIFTHS_URIS_H
+
+#include "lv2/lv2plug.in/ns/ext/log/log.h"
+#include "lv2/lv2plug.in/ns/ext/midi/midi.h"
+#include "lv2/lv2plug.in/ns/ext/state/state.h"
+
+#define EG_FIFTHS_URI          "http://lv2plug.in/plugins/eg-fifths"
+#define EG_FIFTHS__sample      EG_FIFTHS_URI "#sample"
+#define EG_FIFTHS__applySample EG_FIFTHS_URI "#applySample"
+#define EG_FIFTHS__freeSample  EG_FIFTHS_URI "#freeSample"
+
+typedef struct {
+	LV2_URID atom_Blank;
+	LV2_URID atom_Path;
+	LV2_URID atom_Resource;
+	LV2_URID atom_Sequence;
+	LV2_URID atom_URID;
+	LV2_URID atom_eventTransfer;
+	LV2_URID eg_applySample;
+	LV2_URID eg_sample;
+	LV2_URID eg_freeSample;
+	LV2_URID midi_Event;
+	LV2_URID patch_Set;
+	LV2_URID patch_property;
+	LV2_URID patch_value;
+} FifthsURIs;
+
+static inline void
+map_fifths_uris(LV2_URID_Map* map, FifthsURIs* uris)
+{
+	uris->atom_Blank         = map->map(map->handle, LV2_ATOM__Blank);
+	uris->atom_Path          = map->map(map->handle, LV2_ATOM__Path);
+	uris->atom_Resource      = map->map(map->handle, LV2_ATOM__Resource);
+	uris->atom_Sequence      = map->map(map->handle, LV2_ATOM__Sequence);
+	uris->atom_URID          = map->map(map->handle, LV2_ATOM__URID);
+	uris->atom_eventTransfer = map->map(map->handle, LV2_ATOM__eventTransfer);
+	uris->eg_applySample     = map->map(map->handle, EG_FIFTHS__applySample);
+	uris->eg_freeSample      = map->map(map->handle, EG_FIFTHS__freeSample);
+	uris->eg_sample          = map->map(map->handle, EG_FIFTHS__sample);
+	uris->midi_Event         = map->map(map->handle, LV2_MIDI__MidiEvent);
+	uris->patch_Set          = map->map(map->handle, LV2_PATCH__Set);
+	uris->patch_property     = map->map(map->handle, LV2_PATCH__property);
+	uris->patch_value        = map->map(map->handle, LV2_PATCH__value);
+}
+
+#endif  /* FIFTHS_URIS_H */
diff --git a/plugins/eg06-fifths.lv2/waf b/plugins/eg06-fifths.lv2/waf
new file mode 120000
index 0000000..59a1ac9
--- /dev/null
+++ b/plugins/eg06-fifths.lv2/waf
@@ -0,0 +1 @@
+../../waf
\ No newline at end of file
diff --git a/plugins/eg06-fifths.lv2/wscript b/plugins/eg06-fifths.lv2/wscript
new file mode 100644
index 0000000..46e2345
--- /dev/null
+++ b/plugins/eg06-fifths.lv2/wscript
@@ -0,0 +1,64 @@
+#!/usr/bin/env python
+from waflib.extras import autowaf as autowaf
+import re
+
+# Variables for 'waf dist'
+APPNAME = 'eg-fifths.lv2'
+VERSION = '1.0.0'
+
+# Mandatory variables
+top = '.'
+out = 'build'
+
+def options(opt):
+    opt.load('compiler_c')
+    autowaf.set_options(opt)
+
+def configure(conf):
+    conf.load('compiler_c')
+    autowaf.configure(conf)
+    autowaf.set_c99_mode(conf)
+    autowaf.display_header('Fifths Configuration')
+
+    if not autowaf.is_child():
+        autowaf.check_pkg(conf, 'lv2', atleast_version='1.2.1', uselib_store='LV2')
+
+    autowaf.display_msg(conf, 'LV2 bundle directory', conf.env.LV2DIR)
+    print('')
+
+def build(bld):
+    bundle = 'eg-fifths.lv2'
+
+    # Make a pattern for shared objects without the 'lib' prefix
+    module_pat = re.sub('^lib', '', bld.env.cshlib_PATTERN)
+    module_ext = module_pat[module_pat.rfind('.'):]
+
+    # Build manifest.ttl by substitution (for portable lib extension)
+    bld(features     = 'subst',
+        source       = 'manifest.ttl.in',
+        target       = '%s/%s' % (bundle, 'manifest.ttl'),
+        install_path = '${LV2DIR}/%s' % bundle,
+        LIB_EXT      = module_ext)
+    
+    # Copy other data files to build bundle (build/eg-fifths.lv2)
+    for i in ['fifths.ttl']:
+        bld(features     = 'subst',
+            is_copy      = True,
+            source       = i,
+            target       = '%s/%s' % (bundle, i),
+            install_path = '${LV2DIR}/%s' % bundle)
+
+    # Use LV2 headers from parent directory if building as a sub-project
+    includes = ['.']
+    if autowaf.is_child:
+        includes += ['../..']
+
+    # Build plugin library
+    obj = bld(features     = 'c cshlib',
+              source       = 'fifths.c',
+              name         = 'fifths',
+              target       = '%s/fifths' % bundle,
+              install_path = '${LV2DIR}/%s' % bundle,
+              use          = 'SNDFILE LV2',
+              includes     = includes)
+    obj.env.cshlib_PATTERN = module_pat