Add worker extension to remove thread stuff from plugins.

17 files changed, 325 insertions, 986 deletions

diff --git a/doc/reference.doxygen.in b/doc/reference.doxygen.in
index f97a93f..9ed3968 100644
--- a/doc/reference.doxygen.in
+++ b/doc/reference.doxygen.in
@@ -587,6 +587,7 @@ INPUT =  \
 	@LV2_SRCDIR@/lv2/lv2plug.in/ns/ext/ui-resize/ui-resize.h \
 	@LV2_SRCDIR@/lv2/lv2plug.in/ns/ext/uri-map/uri-map.h \
 	@LV2_SRCDIR@/lv2/lv2plug.in/ns/ext/urid/urid.h \
+	@LV2_SRCDIR@/lv2/lv2plug.in/ns/ext/worker/worker.h \
 	@LV2_SRCDIR@/lv2/lv2plug.in/ns/extensions/ui/ui.h \
 	@LV2_SRCDIR@/lv2/lv2plug.in/ns/lv2core/lv2.h
 
diff --git a/lv2/lv2plug.in/ns/ext/atom/forge.h b/lv2/lv2plug.in/ns/ext/atom/forge.h
index 322e14e..ea5977e 100644
--- a/lv2/lv2plug.in/ns/ext/atom/forge.h
+++ b/lv2/lv2plug.in/ns/ext/atom/forge.h
@@ -120,7 +120,6 @@ static inline void
 lv2_atom_forge_init(LV2_Atom_Forge* forge, LV2_URID_Map* map)
 {
 	lv2_atom_forge_set_buffer(forge, NULL, 0);
-	forge->stack    = NULL;
 	forge->Blank    = map->map(map->handle, LV2_ATOM__Blank);
 	forge->Bool     = map->map(map->handle, LV2_ATOM__Bool);
 	forge->Double   = map->map(map->handle, LV2_ATOM__Double);
diff --git a/lv2/lv2plug.in/ns/ext/urid/urid.ttl b/lv2/lv2plug.in/ns/ext/urid/urid.ttl
index 121ffaf..d080107 100644
--- a/lv2/lv2plug.in/ns/ext/urid/urid.ttl
+++ b/lv2/lv2plug.in/ns/ext/urid/urid.ttl
@@ -68,7 +68,7 @@ urid:map
 	lv2:documentation """
 <p>A feature which is used to map URIs to integers.  To support this feature,
 the host must pass an LV2_Feature to LV2_Descriptor::instantiate() with URI
-LV2_URID_MAP_URI and data pointed to an instance of LV2_URID_Map.</p>
+LV2_URID__map and data pointed to an instance of LV2_URID_Map.</p>
 """ .
 
 urid:unmap
@@ -76,6 +76,6 @@ urid:unmap
 	lv2:documentation """
 <p>A feature which is used to unmap URIs previously mapped to integers by
 urid:map.  To support this feature, the host must pass an LV2_Feature to
-LV2_Descriptor::instantiate() with URI LV2_URID_UNMAP_URI and data pointed to
+LV2_Descriptor::instantiate() with URI LV2_URID__unmapl and data pointed to
 an instance of LV2_URID_Unmap.</p>
 """ .
diff --git a/lv2/lv2plug.in/ns/ext/worker/ext.pc.in b/lv2/lv2plug.in/ns/ext/worker/ext.pc.in
new file mode 120000
index 0000000..03dd044
--- /dev/null
+++ b/lv2/lv2plug.in/ns/ext/worker/ext.pc.in
@@ -0,0 +1 @@
+../../../../../ext.pc.in
\ No newline at end of file
diff --git a/lv2/lv2plug.in/ns/ext/worker/manifest.ttl b/lv2/lv2plug.in/ns/ext/worker/manifest.ttl
new file mode 100644
index 0000000..af46f01
--- /dev/null
+++ b/lv2/lv2plug.in/ns/ext/worker/manifest.ttl
@@ -0,0 +1,8 @@
+@prefix lv2:  <http://lv2plug.in/ns/lv2core#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+
+<http://lv2plug.in/ns/ext/worker>
+	a lv2:Specification ;
+	lv2:minorVersion 0 ;
+	lv2:microVersion 1 ;
+	rdfs:seeAlso <worker.ttl> .
diff --git a/lv2/lv2plug.in/ns/ext/worker/waf b/lv2/lv2plug.in/ns/ext/worker/waf
new file mode 120000
index 0000000..5235032
--- /dev/null
+++ b/lv2/lv2plug.in/ns/ext/worker/waf
@@ -0,0 +1 @@
+../../../../../waf
\ No newline at end of file
diff --git a/lv2/lv2plug.in/ns/ext/worker/worker.h b/lv2/lv2plug.in/ns/ext/worker/worker.h
new file mode 100644
index 0000000..612a24c
--- /dev/null
+++ b/lv2/lv2plug.in/ns/ext/worker/worker.h
@@ -0,0 +1,138 @@
+/*
+  Copyright 2012 David Robillard <http://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.
+*/
+
+/**
+   @file worker.h C header for the LV2 Worker extension
+   <http://lv2plug.in/ns/ext/worker>.
+*/
+
+#ifndef LV2_WORKER_H
+#define LV2_WORKER_H
+
+#include <stdint.h>
+
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+
+#define LV2_WORKER_URI    "http://lv2plug.in/ns/ext/worker"
+#define LV2_WORKER_PREFIX LV2_WORKER_URI "#"
+
+#define LV2_WORKER__Interface LV2_WORKER_PREFIX "Interface"
+#define LV2_WORKER__schedule  LV2_WORKER_PREFIX "schedule"
+
+/**
+   A status code for worker functions.
+*/
+typedef enum {
+	LV2_WORKER_SUCCESS       = 0,  /**< Completed successfully. */
+	LV2_WORKER_ERR_UNKNOWN   = 1,  /**< Unknown error. */
+	LV2_WORKER_ERR_NO_SPACE  = 2   /**< Failed due to lack of space. */
+} LV2_Worker_Status;
+
+typedef void* LV2_Worker_Respond_Handle;
+
+/**
+   A function to respond to run() from the worker method.
+
+   The @p data MUST be safe for the host to copy and later pass to
+   work_response(), and the host MUST guarantee that it will be eventually
+   passed to work_response() if this function returns LV2_WORKER_SUCCESS.
+*/
+typedef LV2_Worker_Status (*LV2_Worker_Respond_Function)(
+	LV2_Worker_Respond_Handle handle,
+	uint32_t                  size,
+	const void*               data);
+
+/**
+   LV2 Plugin Worker Interface.
+
+   This is the interface provided by the plugin to implement a worker method.
+   The plugin's extension_data() method should return an LV2_Worker_Interface
+   when called with LV2_WORKER__Interface as its argument.
+*/
+typedef struct _LV2_Worker_Interface {
+	/**
+	   The worker method.  This is called by the host in a non-realtime context
+	   as requested, possibly with an arbitrary message to handle.
+
+	   A response can be sent to run() using @p respond.  The plugin MUST NOT
+	   make any assumptions about which thread calls this method, other than
+	   the fact that there are no real-time requirements.
+
+	   @param instance The LV2 instance this is a method on.
+	   @param respond  A function for sending a response to run().
+	   @param handle   Must be passed to @p respond if it is called.
+	   @param size     The size of @p data.
+	   @param data     Data from run(), or NULL.
+	*/
+	LV2_Worker_Status (*work)(LV2_Handle                  instance,
+	                          LV2_Worker_Respond_Function respond,
+	                          LV2_Worker_Respond_Handle   handle,
+	                          uint32_t                    size,
+	                          const void*                 data);
+
+	/**
+	   Handle a response from the worker.  This is called by the host in the
+	   run() context when a response from the worker is ready.
+
+	   @param instance The LV2 instance this is a method on.
+	   @param size     The size of @p body.
+	   @param body     Message body, or NULL.
+	*/
+	LV2_Worker_Status (*work_response)(LV2_Handle  instance,
+	                                   uint32_t    size,
+	                                   const void* body);
+} LV2_Worker_Interface;
+
+typedef void* LV2_Worker_Schedule_Handle;
+
+typedef struct _LV2_Worker_Schedule {
+	/**
+	   Opaque host data.
+	*/
+	LV2_Worker_Schedule_Handle handle;
+
+	/**
+	   Request from run() that the host call the worker.
+
+	   This function is in the audio threading class.  It should be called from
+	   run() to request that the host call the work() method in a non-realtime
+	   context with the given arguments.
+
+	   This function is always safe to call from run(), but it is not
+	   guaranteed that the worker is actually called from a different thread.
+	   In particular, when free-wheeling (e.g. for offline rendering), the
+	   worker may be executed immediately.  This allows single-threaded
+	   processing with sample accuracy and avoids timing problems when run() is
+	   executing much faster or slower than real-time.
+
+	   Plugins SHOULD be written in such a way that if the worker runs
+	   immediately, and responses from the worker are delivered immediately,
+	   the effect of the work takes place immediately with sample accuracy.
+
+	   The @p data MUST be safe for the host to copy and later pass to work(),
+	   and the host MUST guarantee that it will be eventually passed to work()
+	   if this function returns LV2_WORKER_SUCCESS.
+
+	   @param handle The handle field of this struct.
+	   @param size   The size of @p body.
+	   @param data   Message to pass to work(), or NULL.
+	*/
+	LV2_Worker_Status (*schedule_work)(LV2_Worker_Schedule_Handle handle,
+	                                   uint32_t                   size,
+	                                   const void*                data);
+} LV2_Worker_Schedule;
+
+#endif  /* LV2_WORKER_H */
diff --git a/lv2/lv2plug.in/ns/ext/worker/worker.ttl b/lv2/lv2plug.in/ns/ext/worker/worker.ttl
new file mode 100644
index 0000000..ea49056
--- /dev/null
+++ b/lv2/lv2plug.in/ns/ext/worker/worker.ttl
@@ -0,0 +1,58 @@
+# LV2 Worker Extension
+# Copyright 2012 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.
+
+@prefix work: <http://lv2plug.in/ns/ext/worker#> .
+@prefix lv2:  <http://lv2plug.in/ns/lv2core#> .
+@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix xsd:  <http://www.w3.org/2001/XMLSchema#> .
+@prefix doap: <http://usefulinc.com/ns/doap#> .
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+
+<http://lv2plug.in/ns/ext/worker>
+	a lv2:Specification ,
+		lv2:Feature ;
+	doap:name "LV2 Worker" ;
+	doap:shortdesc "Support for a non-realtime plugin worker method." ;
+	lv2:documentation """
+""" .
+
+work:Interface
+	a rdfs:Class ;
+	rdfs:subClassOf lv2:ExtensionData ;
+	lv2:documentation """
+<p>A structure (LV2_Worker_Interface) which contains the worker method to be
+called by the host.  In order to support this extension, the plugin must return
+a valid LV2_Worker_Interface from LV2_Descriptor::extension_data() when it is
+called with URI LV2_WORKER__Interface.</p>
+
+<p>The plugin data file should describe this like so:</p>
+<pre class="turtle-code">
+@prefix work: &lt;http://lv2plug.in/ns/ext/worker#&gt; .
+
+&lt;plugin&gt;
+    a lv2:Plugin ;
+    lv2:extensionData work:Interface .
+</pre>
+""" .
+
+work:schedule
+	a lv2:Feature ;
+	lv2:documentation """
+<p>A feature which provides functions for use by the plugin to implement a
+worker method.  To support this feature, the host must pass an LV2_Feature to
+LV2_Descriptor::instantiate() with URI LV2_WORKER__schedule and data pointed to
+an instance of LV2_Worker_Schedule.</p>
+""" .
diff --git a/lv2/lv2plug.in/ns/ext/worker/wscript b/lv2/lv2plug.in/ns/ext/worker/wscript
new file mode 120000
index 0000000..7e2c01b
--- /dev/null
+++ b/lv2/lv2plug.in/ns/ext/worker/wscript
@@ -0,0 +1 @@
+../../../../../ext.wscript
\ No newline at end of file
diff --git a/plugins/eg-sampler.lv2/sampler.c b/plugins/eg-sampler.lv2/sampler.c
index ec59ef3..229762e 100644
--- a/plugins/eg-sampler.lv2/sampler.c
+++ b/plugins/eg-sampler.lv2/sampler.c
@@ -44,16 +44,11 @@
 #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/ext/worker/worker.h"
 #include "lv2/lv2plug.in/ns/lv2core/lv2.h"
 
-#include "zix/sem.h"
-#include "zix/thread.h"
-#include "zix/ring.h"
-
 #include "./uris.h"
 
-#define RING_SIZE 4096
-
 enum {
 	SAMPLER_CONTROL  = 0,
 	SAMPLER_RESPONSE = 1,
@@ -71,39 +66,38 @@ typedef struct {
 
 typedef struct {
 	/* Features */
-	LV2_URID_Map* map;
+	LV2_URID_Map*        map;
+	LV2_Worker_Schedule* schedule;
 
 	/* Forge for creating atoms */
 	LV2_Atom_Forge forge;
 
-	/* Worker thread, communication, and sync */
-	ZixThread worker_thread;
-	ZixSem    signal;
-	ZixRing*  to_worker;
-	ZixRing*  from_worker;
-	bool      exit;
-
 	/* Sample */
 	Sample* sample;
 
 	/* Ports */
-	float*             output_port;
-	LV2_Atom_Sequence* control_port;
-	LV2_Atom_Sequence* notify_port;
+	float*               output_port;
+	LV2_Atom_Sequence*   control_port;
+	LV2_Atom_Sequence*   notify_port;
+	LV2_Atom_Forge_Frame notify_frame;
 
 	/* URIs */
 	SamplerURIs uris;
 
+	/* Current position in run() */
+	uint32_t frame_offset;
+
 	/* Playback state */
 	sf_count_t frame;
 	bool       play;
 } Sampler;
 
-/** An atom-like message used internally to apply/free samples.
- *
- * This is only used internally via ringbuffers, since it is not POD and
- * therefore not strictly an Atom.
- */
+/**
+   An atom-like message used internally to apply/free samples.
+ 
+   This is only used internally to communicate with the worker, it is not an
+   Atom because it is not POD.
+*/
 typedef struct {
 	LV2_Atom atom;
 	Sample*  sample;
@@ -120,7 +114,7 @@ load_sample(Sampler* plugin, const char* path)
 	SNDFILE* const sndfile = sf_open(path, SFM_READ, info);
 
 	if (!sndfile || !info->frames || (info->channels != 1)) {
-		fprintf(stderr, "failed to open sample '%s'.\n", path);
+		fprintf(stderr, "Failed to open sample '%s'.\n", path);
 		free(sample);
 		return NULL;
 	}
@@ -128,7 +122,7 @@ load_sample(Sampler* plugin, const char* path)
 	/* Read data */
 	float* const data = malloc(sizeof(float) * info->frames);
 	if (!data) {
-		fprintf(stderr, "failed to allocate memory for sample.\n");
+		fprintf(stderr, "Failed to allocate memory for sample.\n");
 		return NULL;
 	}
 	sf_seek(sndfile, 0ul, SEEK_SET);
@@ -144,32 +138,7 @@ load_sample(Sampler* plugin, const char* path)
 	return sample;
 }
 
-static bool
-handle_set_message(Sampler*               plugin,
-                   const LV2_Atom_Object* obj)
-{
-	/* Get file path from message */
-	const LV2_Atom* file_path = read_set_file(&plugin->uris, obj);
-	if (!file_path) {
-		return false;
-	}
-
-	/* Load sample. */
-	Sample* sample = load_sample(plugin, LV2_ATOM_BODY(file_path));
-	if (sample) {
-		/* Loaded sample, send it to run() to be applied. */
-		const SampleMessage msg = {
-			{ sizeof(sample), plugin->uris.eg_applySample },
-			sample
-		};
-		zix_ring_write(
-			plugin->from_worker, &msg, lv2_atom_pad_size(sizeof(msg)));
-	}
-
-	return true;
-}
-
-void
+static void
 free_sample(Sample* sample)
 {
 	if (sample) {
@@ -180,33 +149,65 @@ free_sample(Sample* sample)
 	}
 }
 
-void*
-worker_thread_main(void* arg)
+/** Handle work (load or free a sample) in a non-realtime thread. */
+static LV2_Worker_Status
+work(LV2_Handle                  instance,
+     LV2_Worker_Respond_Function respond,
+     LV2_Worker_Respond_Handle   handle,
+     uint32_t                    size,
+     const void*                 data)
 {
-	Sampler* plugin = (Sampler*)arg;
-
-	while (!zix_sem_wait(&plugin->signal) && !plugin->exit) {
-		/* Peek message header to see how much we need to read. */
-		LV2_Atom head;
-		zix_ring_peek(plugin->to_worker, &head, sizeof(head));
-
-		/* Read message. */
-		const uint32_t size = lv2_atom_pad_size(sizeof(LV2_Atom) + head.size);
-		uint8_t        buf[size];
-		LV2_Atom*      obj  = (LV2_Atom*)buf;
-		zix_ring_read(plugin->to_worker, buf, size);
-
-		if (obj->type == plugin->uris.eg_freeSample) {
-			/* Free old sample */
-			SampleMessage* msg = (SampleMessage*)obj;
-			free_sample(msg->sample);
-		} else {
-			/* Handle set message (load sample). */
-			handle_set_message(plugin, (LV2_Atom_Object*)obj);
+	Sampler*  self = (Sampler*)instance;
+	LV2_Atom* atom = (LV2_Atom*)data;
+	if (atom->type == self->uris.eg_freeSample) {
+		/* Free old sample */
+		SampleMessage* msg = (SampleMessage*)data;
+		free_sample(msg->sample);
+	} else {
+		/* Handle set message (load sample). */
+		LV2_Atom_Object* obj = (LV2_Atom_Object*)data;
+
+		/* Get file path from message */
+		const LV2_Atom* file_path = read_set_file(&self->uris, obj);
+		if (!file_path) {
+			return LV2_WORKER_ERR_UNKNOWN;
+		}
+
+		/* Load sample. */
+		Sample* sample = load_sample(self, LV2_ATOM_BODY(file_path));
+		if (sample) {
+			/* Loaded sample, send it to run() to be applied. */
+			respond(handle, sizeof(sample), &sample);
 		}
 	}
 
-	return 0;
+	return LV2_WORKER_SUCCESS;
+}
+
+/** Handle a response from work() in the audio thread. */
+static LV2_Worker_Status
+work_response(LV2_Handle  instance,
+              uint32_t    size,
+              const void* data)
+{
+	Sampler* self = (Sampler*)instance;
+
+	SampleMessage msg = { { sizeof(Sample*), self->uris.eg_freeSample },
+	                      self->sample };
+
+	/* Send a message to the worker to free the current sample */
+	self->schedule->schedule_work(self->schedule->handle, sizeof(msg), &msg);
+	                         
+	/* Install the new sample */
+	self->sample = *(Sample**)data;
+
+	/* Send a notification that we're using a new sample. */
+	lv2_atom_forge_frame_time(&self->forge, self->frame_offset);
+	write_set_file(&self->forge, &self->uris,
+	               self->sample->path,
+	               self->sample->path_len);
+
+	return LV2_WORKER_SUCCESS;
 }
 
 static void
@@ -242,52 +243,34 @@ instantiate(const LV2_Descriptor*     descriptor,
 		return NULL;
 	}
 
+	memset(plugin, 0, sizeof(Sampler));
 	plugin->sample = (Sample*)malloc(sizeof(Sample));
 	if (!plugin->sample) {
 		return NULL;
 	}
 
 	memset(plugin->sample, 0, sizeof(Sample));
-	memset(&plugin->uris, 0, sizeof(plugin->uris));
 
-	/* Scan host features for URID map */
-	LV2_URID_Map* map = NULL;
+	/* Scan and store host features */
 	for (int i = 0; features[i]; ++i) {
-		if (!strcmp(features[i]->URI, LV2_URID_URI "#map")) {
-			map = (LV2_URID_Map*)features[i]->data;
+		if (!strcmp(features[i]->URI, LV2_URID__map)) {
+			plugin->map = (LV2_URID_Map*)features[i]->data;
+		} else if (!strcmp(features[i]->URI, LV2_WORKER__schedule)) {
+			plugin->schedule = (LV2_Worker_Schedule*)features[i]->data;
 		}
 	}
-	if (!map) {
+	if (!plugin->map) {
 		fprintf(stderr, "Host does not support urid:map.\n");
 		goto fail;
+	} else if (!plugin->schedule) {
+		fprintf(stderr, "Host does not support work:schedule.\n");
+		goto fail;
 	}
 
 	/* Map URIS and initialise forge */
-	plugin->map = map;
 	map_sampler_uris(plugin->map, &plugin->uris);
 	lv2_atom_forge_init(&plugin->forge, plugin->map);
 
-	/* Create signal for waking up worker thread */
-	if (zix_sem_init(&plugin->signal, 0)) {
-		fprintf(stderr, "Could not initialize semaphore.\n");
-		goto fail;
-	}
-
-	/* Create worker thread */
-	plugin->exit = false;
-	if (zix_thread_create(
-		    &plugin->worker_thread, 1024, worker_thread_main, plugin)) {
-		fprintf(stderr, "Could not initialize worker thread.\n");
-		goto fail;
-	}
-
-	/* Create ringbuffers for communicating with worker thread */
-	plugin->to_worker   = zix_ring_new(RING_SIZE);
-	plugin->from_worker = zix_ring_new(RING_SIZE);
-
-	zix_ring_mlock(plugin->to_worker);
-	zix_ring_mlock(plugin->from_worker);
-
 	/* Load the default sample file */
 	const size_t path_len    = strlen(path);
 	const size_t file_len    = strlen(default_sample_file);
@@ -308,12 +291,6 @@ cleanup(LV2_Handle instance)
 {
 	Sampler* plugin = (Sampler*)instance;
 
-	plugin->exit = true;
-	zix_sem_post(&plugin->signal);
-	zix_thread_join(plugin->worker_thread, 0);
-	zix_sem_destroy(&plugin->signal);
-	zix_ring_free(plugin->to_worker);
-	zix_ring_free(plugin->from_worker);
 	free_sample(plugin->sample);
 	free(plugin);
 }
@@ -328,9 +305,19 @@ run(LV2_Handle instance,
 	sf_count_t   pos         = 0;
 	float*       output      = plugin->output_port;
 
+	/* Set up forge to write directly to notify output port. */
+	const uint32_t notify_capacity = plugin->notify_port->atom.size;
+	lv2_atom_forge_set_buffer(&plugin->forge,
+	                          (uint8_t*)plugin->notify_port,
+	                          notify_capacity);
+
+	/* Start a sequence in the notify output port. */
+	lv2_atom_forge_sequence_head(&plugin->forge, &plugin->notify_frame, 0);
+
 	/* Read incoming events */
 	LV2_SEQUENCE_FOREACH(plugin->control_port, i) {
 		LV2_Atom_Event* const ev = lv2_sequence_iter_get(i);
+		plugin->frame_offset = ev->time.frames;
 		if (ev->body.type == uris->midi_Event) {
 			uint8_t* const data = (uint8_t* const)(ev + 1);
 			if ((data[0] & 0xF0) == 0x90) {
@@ -341,13 +328,11 @@ run(LV2_Handle instance,
 		} else if (is_object_type(uris, ev->body.type)) {
 			const LV2_Atom_Object* obj = (LV2_Atom_Object*)&ev->body;
 			if (obj->body.otype == uris->patch_Set) {
-				/* Received a set message, send it to the worker thread. */
+				/* Received a set message, send it to the worker. */
 				fprintf(stderr, "Queueing set message\n");
-				zix_ring_write(plugin->to_worker,
-				               obj,
-				               lv2_atom_pad_size(
-					               lv2_atom_total_size(&obj->atom)));
-				zix_sem_post(&plugin->signal);
+				plugin->schedule->schedule_work(plugin->schedule->handle,
+				                                lv2_atom_total_size(&ev->body),
+				                                &ev->body);
 			} else {
 				fprintf(stderr, "Unknown object type %d\n", obj->body.otype);
 			}
@@ -380,47 +365,6 @@ run(LV2_Handle instance,
 	for (; pos < sample_count; ++pos) {
 		output[pos] = 0.0f;
 	}
-
-	/* Set up forge to write directly to notify output port buffer */
-	const uint32_t notify_capacity = plugin->notify_port->atom.size;
-
-	lv2_atom_forge_set_buffer(&plugin->forge,
-	                          (uint8_t*)plugin->notify_port,
-	                          notify_capacity);
-
-	LV2_Atom_Forge_Frame seq_frame;
-	lv2_atom_forge_sequence_head(&plugin->forge, &seq_frame, 0);
-
-	/* Read messages from worker thread */
-	SampleMessage  m;
-	const uint32_t msize = lv2_atom_pad_size(sizeof(m));
-	while (zix_ring_read(plugin->from_worker, &m, msize) == msize) {
-		if (m.atom.type == uris->eg_applySample) {
-			/* Send a message to the worker to free the current sample */
-			SampleMessage free_msg = {
-				{ sizeof(plugin->sample), uris->eg_freeSample },
-				plugin->sample
-			};
-			zix_ring_write(plugin->to_worker,
-			               &free_msg,
-			               lv2_atom_pad_size(sizeof(free_msg)));
-			zix_sem_post(&plugin->signal);
-
-			/* Install the new sample */
-			plugin->sample = m.sample;
-
-			/* Send a notification that we're using a new sample. */
-			lv2_atom_forge_frame_time(&plugin->forge, 0);
-			write_set_file(&plugin->forge, uris,
-			               plugin->sample->path,
-			               plugin->sample->path_len);
-
-		} else {
-			fprintf(stderr, "Unknown message from worker\n");
-		}
-	}
-
-	lv2_atom_forge_pop(&plugin->forge, &seq_frame);
 }
 
 static void
@@ -477,12 +421,15 @@ restore(LV2_Handle                  instance,
 	}
 }
 
-const void*
+static const void*
 extension_data(const char* uri)
 {
-	static const LV2_State_Interface state = { save, restore };
+	static const LV2_State_Interface  state  = { save, restore };
+	static const LV2_Worker_Interface worker = { work, work_response };
 	if (!strcmp(uri, LV2_STATE__Interface)) {
 		return &state;
+	} else if (!strcmp(uri, LV2_WORKER__Interface)) {
+		return &worker;
 	}
 	return NULL;
 }
diff --git a/plugins/eg-sampler.lv2/sampler.ttl b/plugins/eg-sampler.lv2/sampler.ttl
index fa93ba4..a70be7b 100644
--- a/plugins/eg-sampler.lv2/sampler.ttl
+++ b/plugins/eg-sampler.lv2/sampler.ttl
@@ -21,12 +21,14 @@
 @prefix lv2:  <http://lv2plug.in/ns/lv2core#> .
 @prefix ui:   <http://lv2plug.in/ns/extensions/ui#> .
 @prefix urid: <http://lv2plug.in/ns/ext/urid#> .
+@prefix work: <http://lv2plug.in/ns/ext/worker#> .
 
 <http://lv2plug.in/plugins/eg-sampler>
 	a lv2:Plugin ;
 	doap:name "Example Sampler" ;
 	doap:license <http://opensource.org/licenses/isc> ;
-	lv2:requiredFeature urid:map ;
+	lv2:requiredFeature urid:map ,
+		work:schedule ;
 	lv2:optionalFeature lv2:hardRTCapable ;
 	lv2:extensionData <http://lv2plug.in/ns/ext/state#Interface> ;
 	ui:ui <http://lv2plug.in/plugins/eg-sampler#ui> ;
@@ -38,7 +40,7 @@
 			<http://lv2plug.in/ns/ext/patch#Message> ;
 		lv2:index 0 ;
 		lv2:symbol "control" ;
-		lv2:name "Control"
+		lv2:name "Control" ;
 	] , [
 		a lv2:OutputPort ,
 			atom:MessagePort ;
@@ -46,13 +48,13 @@
 		atom:supports <http://lv2plug.in/ns/ext/patch#Message> ;
 		lv2:index 1 ;
 		lv2:symbol "notify" ;
-		lv2:name "Notify"
+		lv2:name "Notify" ;
 	] , [
 		a lv2:AudioPort ,
 			lv2:OutputPort ;
 		lv2:index 2 ;
 		lv2:symbol "out" ;
-		lv2:name "Out"
+		lv2:name "Out" ;
 	] .
 
 <http://lv2plug.in/plugins/eg-sampler#ui>
@@ -61,5 +63,5 @@
 	ui:portNotification [
 		ui:plugin <http://lv2plug.in/plugins/eg-sampler> ;
 		lv2:symbol "notify" ;
-        ui:notifyType atom:Blank ;
+		ui:notifyType atom:Blank ;
 	] .
diff --git a/plugins/eg-sampler.lv2/wscript b/plugins/eg-sampler.lv2/wscript
index c25b28d..1f3ec04 100644
--- a/plugins/eg-sampler.lv2/wscript
+++ b/plugins/eg-sampler.lv2/wscript
@@ -31,6 +31,8 @@ def configure(conf):
                           uselib_store='LV2_PATCH')
         autowaf.check_pkg(conf, 'lv2-lv2plug.in-ns-ext-state',
                           uselib_store='LV2_STATE')
+        autowaf.check_pkg(conf, 'lv2-lv2plug.in-ns-ext-worker',
+                          uselib_store='LV2_WORKER')
 
     conf.check(function_name='mlock',
                header_name='sys/mman.h',
@@ -85,11 +87,11 @@ def build(bld):
     # Build plugin library
     obj = bld(features     = 'c cshlib',
               env          = penv,
-              source       = ['sampler.c', 'zix/ring.c'],
+              source       = ['sampler.c'],
               name         = 'sampler',
               target       = '%s/sampler' % bundle,
               install_path = '${LV2DIR}/%s' % bundle,
-              use          = 'SNDFILE LV2CORE LV2_URID LV2_ATOM LV2_STATE LV2_MESSAGE',
+              use          = 'SNDFILE LV2CORE LV2_URID LV2_ATOM LV2_STATE LV2_PATCH LV2_WORKER',
               includes     = includes)
 
     # Build UI library
@@ -100,6 +102,6 @@ def build(bld):
                   name         = 'sampler_ui',
                   target       = '%s/sampler_ui' % bundle,
                   install_path = '${LV2DIR}/%s' % bundle,
-                  use          = 'GTK2 LV2CORE LV2_URID LV2_ATOM LV2_STATE LV2_MESSAGE',
+                  use          = 'GTK2 LV2CORE LV2_URID LV2_ATOM LV2_PATCH',
                   includes     = includes)
 
diff --git a/plugins/eg-sampler.lv2/zix/common.h b/plugins/eg-sampler.lv2/zix/common.h
deleted file mode 100644
index f113cfe..0000000
--- a/plugins/eg-sampler.lv2/zix/common.h
+++ /dev/null
@@ -1,83 +0,0 @@
-/*
-  Copyright 2011-2012 David Robillard <http://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 ZIX_COMMON_H
-#define ZIX_COMMON_H
-
-/**
-   @addtogroup zix
-   @{
-*/
-
-/** @cond */
-#ifdef ZIX_SHARED
-#    ifdef _WIN32
-#        define ZIX_LIB_IMPORT __declspec(dllimport)
-#        define ZIX_LIB_EXPORT __declspec(dllexport)
-#    else
-#        define ZIX_LIB_IMPORT __attribute__((visibility("default")))
-#        define ZIX_LIB_EXPORT __attribute__((visibility("default")))
-#    endif
-#    ifdef ZIX_INTERNAL
-#        define ZIX_API ZIX_LIB_EXPORT
-#    else
-#        define ZIX_API ZIX_LIB_IMPORT
-#    endif
-#else
-#    define ZIX_API
-#endif
-/** @endcond */
-
-#ifdef __cplusplus
-extern "C" {
-#else
-#    include <stdbool.h>
-#endif
-
-typedef enum {
-	ZIX_STATUS_SUCCESS,
-	ZIX_STATUS_ERROR,
-	ZIX_STATUS_NO_MEM,
-	ZIX_STATUS_NOT_FOUND,
-	ZIX_STATUS_EXISTS,
-	ZIX_STATUS_BAD_ARG,
-	ZIX_STATUS_BAD_PERMS,
-} ZixStatus;
-
-/**
-   Function for comparing two elements.
-*/
-typedef int (*ZixComparator)(const void* a, const void* b, void* user_data);
-
-/**
-   Function for testing equality of two elements.
-*/
-typedef bool (*ZixEqualFunc)(const void* a, const void* b);
-
-/**
-   Function to destroy an element.
-*/
-typedef void (*ZixDestroyFunc)(void* ptr);
-
-/**
-   @}
-*/
-
-#ifdef __cplusplus
-}  /* extern "C" */
-#endif
-
-#endif  /* ZIX_COMMON_H */
diff --git a/plugins/eg-sampler.lv2/zix/ring.c b/plugins/eg-sampler.lv2/zix/ring.c
deleted file mode 100644
index 29d415c..0000000
--- a/plugins/eg-sampler.lv2/zix/ring.c
+++ /dev/null
@@ -1,231 +0,0 @@
-/*
-  Copyright 2011-2012 David Robillard <http://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 <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-
-#ifdef HAVE_MLOCK
-#    include <sys/mman.h>
-#    define ZIX_MLOCK(ptr, size) mlock((ptr), (size))
-#elif defined(_WIN32)
-#    include <windows.h>
-#    define ZIX_MLOCK(ptr, size) VirtualLock((ptr), (size))
-#else
-#    pragma message("warning: No memory locking, possible RT violations")
-#    define ZIX_MLOCK(ptr, size)
-#endif
-
-#if defined(__APPLE__)
-#    include <libkern/OSAtomic.h>
-#    define ZIX_FULL_BARRIER() OSMemoryBarrier()
-#elif defined(_WIN32)
-#    include <windows.h>
-#    define ZIX_FULL_BARRIER() MemoryBarrier()
-#elif (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)
-#    define ZIX_FULL_BARRIER() __sync_synchronize()
-#else
-#    pragma message("warning: No memory barriers, possible SMP bugs")
-#    define ZIX_FULL_BARRIER()
-#endif
-
-/* No support for any systems with separate read and write barriers */
-#define ZIX_READ_BARRIER() ZIX_FULL_BARRIER()
-#define ZIX_WRITE_BARRIER() ZIX_FULL_BARRIER()
-
-#include "zix/ring.h"
-
-struct ZixRingImpl {
-	uint32_t write_head;  ///< Read index into buf
-	uint32_t read_head;   ///< Write index into buf
-	uint32_t size;        ///< Size (capacity) in bytes
-	uint32_t size_mask;   ///< Mask for fast modulo
-	char*    buf;         ///< Contents
-};
-
-static inline uint32_t
-next_power_of_two(uint32_t size)
-{
-	// http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
-	size--;
-	size |= size >> 1;
-	size |= size >> 2;
-	size |= size >> 4;
-	size |= size >> 8;
-	size |= size >> 16;
-	size++;
-	return size;
-}
-
-ZixRing*
-zix_ring_new(uint32_t size)
-{
-	ZixRing* ring = (ZixRing*)malloc(sizeof(ZixRing));
-	ring->write_head = 0;
-	ring->read_head  = 0;
-	ring->size       = next_power_of_two(size);
-	ring->size_mask  = ring->size - 1;
-	ring->buf        = (char*)malloc(ring->size);
-	return ring;
-}
-
-void
-zix_ring_free(ZixRing* ring)
-{
-	free(ring->buf);
-	free(ring);
-}
-
-void
-zix_ring_mlock(ZixRing* ring)
-{
-	ZIX_MLOCK(ring, sizeof(ZixRing));
-	ZIX_MLOCK(ring->buf, ring->size);
-}
-
-void
-zix_ring_reset(ZixRing* ring)
-{
-	ring->write_head = 0;
-	ring->read_head  = 0;
-}
-
-static inline uint32_t
-read_space_internal(const ZixRing* ring, uint32_t r, uint32_t w)
-{
-	if (r < w) {
-		return w - r;
-	} else {
-		return (w - r + ring->size) & ring->size_mask;
-	}
-}
-
-uint32_t
-zix_ring_read_space(const ZixRing* ring)
-{
-	return read_space_internal(ring, ring->read_head, ring->write_head);
-}
-
-static inline uint32_t
-write_space_internal(const ZixRing* ring, uint32_t r, uint32_t w)
-{
-	if (r == w) {
-		return ring->size - 1;
-	} else if (r < w) {
-		return ((r - w + ring->size) & ring->size_mask) - 1;
-	} else {
-		return (r - w) - 1;
-	}
-}
-
-uint32_t
-zix_ring_write_space(const ZixRing* ring)
-{
-	return write_space_internal(ring, ring->read_head, ring->write_head);
-}
-
-uint32_t
-zix_ring_capacity(const ZixRing* ring)
-{
-	return ring->size - 1;
-}
-
-static inline uint32_t
-peek_internal(const ZixRing* ring, uint32_t r, uint32_t w,
-              uint32_t size, void* dst)
-{
-	if (read_space_internal(ring, r, w) < size) {
-		return 0;
-	}
-
-	if (r + size < ring->size) {
-		memcpy(dst, &ring->buf[r], size);
-	} else {
-		const uint32_t first_size = ring->size - r;
-		memcpy(dst, &ring->buf[r], first_size);
-		memcpy((char*)dst + first_size, &ring->buf[0], size - first_size);
-	}
-
-	return size;
-}
-
-uint32_t
-zix_ring_peek(ZixRing* ring, void* dst, uint32_t size)
-{
-	const uint32_t r = ring->read_head;
-	const uint32_t w = ring->write_head;
-
-	return peek_internal(ring, r, w, size, dst);
-}
-
-uint32_t
-zix_ring_read(ZixRing* ring, void* dst, uint32_t size)
-{
-	const uint32_t r = ring->read_head;
-	const uint32_t w = ring->write_head;
-
-	if (peek_internal(ring, r, w, size, dst)) {
-		ZIX_READ_BARRIER();
-		ring->read_head = (r + size) & ring->size_mask;
-		return size;
-	} else {
-		return 0;
-	}
-}
-
-uint32_t
-zix_ring_skip(ZixRing* ring, uint32_t size)
-{
-	const uint32_t r = ring->read_head;
-	const uint32_t w = ring->write_head;
-	if (read_space_internal(ring, r, w) < size) {
-		return 0;
-	}
-
-	ZIX_READ_BARRIER();
-	ring->read_head = (r + size) & ring->size_mask;
-	return size;
-}
-
-uint32_t
-zix_ring_write(ZixRing* ring, const void* src, uint32_t size)
-{
-	const uint32_t r = ring->read_head;
-	const uint32_t w = ring->write_head;
-	if (write_space_internal(ring, r, w) < size) {
-		return 0;
-	}
-
-	if (w + size <= ring->size) {
-		memcpy(&ring->buf[w], src, size);
-		ZIX_WRITE_BARRIER();
-		ring->write_head = (w + size) & ring->size_mask;
-	} else {
-		const uint32_t this_size = ring->size - w;
-		memcpy(&ring->buf[w], src, this_size);
-		memcpy(&ring->buf[0], (char*)src + this_size, size - this_size);
-		ZIX_WRITE_BARRIER();
-		ring->write_head = size - this_size;
-	}
-
-	return size;
-}
-
-void*
-zix_ring_write_head(ZixRing* ring)
-{
-	return &ring->buf[ring->write_head];
-}
diff --git a/plugins/eg-sampler.lv2/zix/ring.h b/plugins/eg-sampler.lv2/zix/ring.h
deleted file mode 100644
index dd45769..0000000
--- a/plugins/eg-sampler.lv2/zix/ring.h
+++ /dev/null
@@ -1,136 +0,0 @@
-/*
-  Copyright 2011-2012 David Robillard <http://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 ZIX_RING_H
-#define ZIX_RING_H
-
-#include <stdint.h>
-
-#include "zix/common.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
-   @addtogroup zix
-   @{
-   @name Ring
-   @{
-*/
-
-/**
-   A lock-free ring buffer.
-
-   Thread-safe with a single reader and single writer, and realtime safe
-   on both ends.
-*/
-typedef struct ZixRingImpl ZixRing;
-
-/**
-   Create a new ring.
-   @param size Size in bytes (note this may be rounded up).
-
-   At most @c size - 1 bytes may be stored in the ring at once.
-*/
-ZixRing*
-zix_ring_new(uint32_t size);
-
-/**
-   Destroy a ring.
-*/
-void
-zix_ring_free(ZixRing* ring);
-
-/**
-   Lock the ring data into physical memory.
-
-   This function is NOT thread safe or real-time safe, but it should be called
-   after zix_ring_new() to lock all ring memory to avoid page faults while
-   using the ring (i.e. this function MUST be called first in order for the
-   ring to be truly real-time safe).
-
-*/
-void
-zix_ring_mlock(ZixRing* ring);
-
-/**
-   Reset (empty) a ring.
-
-   This function is NOT thread-safe, it may only be called when there are no
-   readers or writers.
-*/
-void
-zix_ring_reset(ZixRing* ring);
-
-/**
-   Return the number of bytes of space available for reading.
-*/
-uint32_t
-zix_ring_read_space(const ZixRing* ring);
-
-/**
-   Return the number of bytes of space available for writing.
-*/
-uint32_t
-zix_ring_write_space(const ZixRing* ring);
-
-/**
-   Return the capacity (i.e. total write space when empty).
-*/
-uint32_t
-zix_ring_capacity(const ZixRing* ring);
-
-/**
-   Read from the ring without advancing the read head.
-*/
-uint32_t
-zix_ring_peek(ZixRing* ring, void* dst, uint32_t size);
-
-/**
-   Read from the ring and advance the read head.
-*/
-uint32_t
-zix_ring_read(ZixRing* ring, void* dst, uint32_t size);
-
-/**
-   Skip data in the ring (advance read head without reading).
-*/
-uint32_t
-zix_ring_skip(ZixRing* ring, uint32_t size);
-
-/**
-   Write data to the ring.
-*/
-uint32_t
-zix_ring_write(ZixRing* ring, const void* src, uint32_t size);
-
-/**
-   Return a pointer to the current position of the write head.
-*/
-void*
-zix_ring_write_head(ZixRing* ring);
-
-/**
-   @}
-   @}
-*/
-
-#ifdef __cplusplus
-}  /* extern "C" */
-#endif
-
-#endif  /* ZIX_RING_H */
diff --git a/plugins/eg-sampler.lv2/zix/sem.h b/plugins/eg-sampler.lv2/zix/sem.h
deleted file mode 100644
index d536c99..0000000
--- a/plugins/eg-sampler.lv2/zix/sem.h
+++ /dev/null
@@ -1,236 +0,0 @@
-/*
-  Copyright 2012-2012 David Robillard <http://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 ZIX_SEM_H
-#define ZIX_SEM_H
-
-#ifdef __APPLE__
-#    include <mach/mach.h>
-#elif defined(_WIN32)
-#    include <windows.h>
-#else
-#    include <semaphore.h>
-#    include <errno.h>
-#endif
-
-#include "zix/common.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
-   @addtogroup zix
-   @{
-   @name Semaphore
-   @{
-*/
-
-/**
-   A counting semaphore.
-
-   This is an integer that is always positive, and has two main operations:
-   increment (post) and decrement (wait).  If a decrement can not be performed
-   (i.e. the value is 0) the caller will be blocked until another thread posts
-   and the operation can succeed.
-
-   Semaphores can be created with any starting value, but typically this will
-   be 0 so the semaphore can be used as a simple signal where each post
-   corresponds to one wait.
-
-   Semaphores are very efficient (much moreso than a mutex/cond pair).  In
-   particular, at least on Linux, post is async-signal-safe, which means it
-   does not block and will not be interrupted.  If you need to signal from
-   a realtime thread, this is the most appropriate primitive to use.
-*/
-typedef struct ZixSemImpl ZixSem;
-
-/**
-   Create and initialize @c sem to @c initial.
-*/
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned initial);
-
-/**
-   Destroy @c sem.
-*/
-static inline void
-zix_sem_destroy(ZixSem* sem);
-
-/**
-   Increment (and signal any waiters).
-   Realtime safe.
-*/
-static inline void
-zix_sem_post(ZixSem* sem);
-
-/**
-   Wait until count is > 0, then decrement.
-   Obviously not realtime safe.
-*/
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem);
-
-/**
-   Non-blocking version of wait().
-
-   @return true if decrement was successful (lock was acquired).
-*/
-static inline bool
-zix_sem_try_wait(ZixSem* sem);
-
-/**
-   @cond
-*/
-
-#ifdef __APPLE__
-
-struct ZixSemImpl {
-	semaphore_t sem;
-};
-
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned initial)
-{
-	return semaphore_create(mach_task_self(), &sem->sem, SYNC_POLICY_FIFO, 0)
-		? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS;
-}
-
-static inline void
-zix_sem_destroy(ZixSem* sem)
-{
-	semaphore_destroy(mach_task_self(), sem->sem);
-}
-
-static inline void
-zix_sem_post(ZixSem* sem)
-{
-	semaphore_signal(sem->sem);
-}
-
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem)
-{
-	if (semaphore_wait(sem->sem) != KERN_SUCCESS) {
-		return ZIX_STATUS_ERROR;
-	}
-	return ZIX_STATUS_SUCCESS;
-}
-
-static inline bool
-zix_sem_try_wait(ZixSem* sem)
-{
-	const mach_timespec_t zero = { 0, 0 };
-	return semaphore_timedwait(sem->sem, zero) == KERN_SUCCESS;
-}
-
-#elif defined(_WIN32)
-
-struct ZixSemImpl {
-	HANDLE sem;
-};
-
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned initial)
-{
-	sem->sem = CreateSemaphore(NULL, initial, LONG_MAX, NULL);
-	return (sem->sem) ? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS;
-}
-
-static inline void
-zix_sem_destroy(ZixSem* sem)
-{
-	CloseHandle(sem->sem);
-}
-
-static inline void
-zix_sem_post(ZixSem* sem)
-{
-	ReleaseSemaphore(sem->sem, 1, NULL);
-}
-
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem)
-{
-	if (WaitForSingleObject(sem->sem, INFINITE) != WAIT_OBJECT_0) {
-		return ZIX_STATUS_ERROR;
-	}
-	return ZIX_STATUS_SUCCESS;
-}
-
-static inline bool
-zix_sem_try_wait(ZixSem* sem)
-{
-	WaitForSingleObject(sem->sem, 0);
-}
-
-#else  /* !defined(__APPLE__) && !defined(_WIN32) */
-
-struct ZixSemImpl {
-	sem_t sem;
-};
-
-static inline ZixStatus
-zix_sem_init(ZixSem* sem, unsigned initial)
-{
-	return sem_init(&sem->sem, 0, initial)
-		? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS;
-}
-
-static inline void
-zix_sem_destroy(ZixSem* sem)
-{
-	sem_destroy(&sem->sem);
-}
-
-static inline void
-zix_sem_post(ZixSem* sem)
-{
-	sem_post(&sem->sem);
-}
-
-static inline ZixStatus
-zix_sem_wait(ZixSem* sem)
-{
-	while (sem_wait(&sem->sem)) {
-		if (errno != EINTR) {
-			return ZIX_STATUS_ERROR;
-		}
-		/* Otherwise, interrupted, so try again. */
-	}
-
-	return ZIX_STATUS_SUCCESS;
-}
-
-static inline bool
-zix_sem_try_wait(ZixSem* sem)
-{
-	return (sem_trywait(&sem->sem) == 0);
-}
-
-#endif
-
-/**
-   @endcond
-   @}
-   @}
-*/
-
-#ifdef __cplusplus
-}  /* extern "C" */
-#endif
-
-#endif  /* ZIX_SEM_H */
diff --git a/plugins/eg-sampler.lv2/zix/thread.h b/plugins/eg-sampler.lv2/zix/thread.h
deleted file mode 100644
index 602b701..0000000
--- a/plugins/eg-sampler.lv2/zix/thread.h
+++ /dev/null
@@ -1,133 +0,0 @@
-/*
-  Copyright 2012-2012 David Robillard <http://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 ZIX_THREAD_H
-#define ZIX_THREAD_H
-
-#ifdef _WIN32
-#    include <windows.h>
-#else
-#    include <errno.h>
-#    include <pthread.h>
-#endif
-
-#include "zix/common.h"
-
-#ifdef __cplusplus
-extern "C" {
-#else
-#    include <stdbool.h>
-#endif
-
-/**
-   @addtogroup zix
-   @{
-   @name Thread
-   @{
-*/
-
-#ifdef _WIN32
-typedef HANDLE ZixThread;
-#else
-typedef pthread_t ZixThread;
-#endif
-
-/**
-   Initialize @c thread to a new thread.
-
-   The thread will immediately be launched, calling @c function with @c arg
-   as the only parameter.
-*/
-static inline ZixStatus
-zix_thread_create(ZixThread* thread,
-                  size_t     stack_size,
-                  void*      (*function)(void*),
-                  void*      arg);
-
-/**
-   Join @c thread (block until @c thread exits).
-*/
-static inline ZixStatus
-zix_thread_join(ZixThread thread, void** retval);
-
-#ifdef _WIN32
-
-static inline ZixStatus
-zix_thread_create(ZixThread* thread,
-                  size_t     stack_size,
-                  void*      (*function)(void*),
-                  void*      arg)
-{
-	*thread = CreateThread(NULL, stack_size,
-	                       (LPTHREAD_START_ROUTINE)function, arg,
-	                       0, NULL);
-	return *thread ? ZIX_STATUS_SUCCESS : ZIX_STATUS_ERROR;
-}
-
-static inline ZixStatus
-zix_thread_join(ZixThread thread, void** retval)
-{
-	return WaitForSingleObject(thread, INFINITE)
-		? ZIX_STATUS_SUCCESS : ZIX_STATUS_ERROR;
-}
-
-#else  /* !defined(_WIN32) */
-
-static inline ZixStatus
-zix_thread_create(ZixThread* thread,
-                  size_t     stack_size,
-                  void*      (*function)(void*),
-                  void*      arg)
-{
-	pthread_attr_t attr;
-	pthread_attr_init(&attr);
-	pthread_attr_setstacksize(&attr, stack_size);
-
-	const int ret = pthread_create(thread, NULL, function, arg);
-	pthread_attr_destroy(&attr);
-
-	if (ret == EAGAIN) {
-		return ZIX_STATUS_NO_MEM;
-	} else if (ret == EINVAL) {
-		return ZIX_STATUS_BAD_ARG;
-	} else if (ret == EPERM) {
-		return ZIX_STATUS_BAD_PERMS;
-	} else if (ret) {
-		return ZIX_STATUS_ERROR;
-	}
-
-	return ZIX_STATUS_SUCCESS;
-}
-
-static inline ZixStatus
-zix_thread_join(ZixThread thread, void** retval)
-{
-	return pthread_join(thread, retval)
-		? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS;
-}
-
-#endif
-
-/**
-   @}
-   @}
-*/
-
-#ifdef __cplusplus
-}  /* extern "C" */
-#endif
-
-#endif  /* ZIX_THREAD_H */