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-rw-r--r--plugins/eg-sampler.lv2/sampler.c603
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diff --git a/plugins/eg-sampler.lv2/sampler.c b/plugins/eg-sampler.lv2/sampler.c
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+++ b/plugins/eg-sampler.lv2/sampler.c
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+/*
+ LV2 Sampler Example Plugin
+ Copyright 2011-2016 David Robillard <d@drobilla.net>
+ Copyright 2011 Gabriel M. Beddingfield <gabriel@teuton.org>
+ Copyright 2011 James Morris <jwm.art.net@gmail.com>
+
+ 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/forge.h"
+#include "lv2/lv2plug.in/ns/ext/atom/util.h"
+#include "lv2/lv2plug.in/ns/ext/log/log.h"
+#include "lv2/lv2plug.in/ns/ext/log/logger.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/ext/worker/worker.h"
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+#include "lv2/lv2plug.in/ns/lv2core/lv2_util.h"
+
+#include "atom_sink.h"
+#include "peaks.h"
+#include "uris.h"
+
+enum {
+ SAMPLER_CONTROL = 0,
+ SAMPLER_NOTIFY = 1,
+ SAMPLER_OUT = 2
+};
+
+typedef struct {
+ SF_INFO info; // Info about sample from sndfile
+ float* data; // Sample data in float
+ char* path; // Path of file
+ uint32_t path_len; // Length of path
+} Sample;
+
+typedef struct {
+ // Features
+ LV2_URID_Map* map;
+ LV2_Worker_Schedule* schedule;
+ LV2_Log_Logger logger;
+
+ // Ports
+ const LV2_Atom_Sequence* control_port;
+ LV2_Atom_Sequence* notify_port;
+ float* output_port;
+
+ // Communication utilities
+ LV2_Atom_Forge_Frame notify_frame; ///< Cached for worker replies
+ LV2_Atom_Forge forge; ///< Forge for writing atoms in run thread
+ PeaksSender psend; ///< Audio peaks sender
+
+ // URIs
+ SamplerURIs uris;
+
+ // Playback state
+ Sample* sample;
+ uint32_t frame_offset;
+ float gain;
+ sf_count_t frame;
+ bool play;
+ bool activated;
+ bool sample_changed;
+} Sampler;
+
+/**
+ An atom-like message used internally to apply/free samples.
+
+ This is only used internally to communicate with the worker, it is never
+ sent to the outside world via a port since it is not POD. It is convenient
+ to use an Atom header so actual atoms can be easily sent through the same
+ ringbuffer.
+*/
+typedef struct {
+ LV2_Atom atom;
+ Sample* sample;
+} SampleMessage;
+
+/**
+ Load a new sample and return it.
+
+ Since this is of course not a real-time safe action, this is called in the
+ worker thread only. The sample is loaded and returned only, plugin state is
+ not modified.
+*/
+static Sample*
+load_sample(LV2_Log_Logger* logger, const char* path)
+{
+ lv2_log_trace(logger, "Loading %s\n", path);
+
+ const size_t path_len = strlen(path);
+ Sample* const sample = (Sample*)calloc(1, sizeof(Sample));
+ SF_INFO* const info = &sample->info;
+ SNDFILE* const sndfile = sf_open(path, SFM_READ, info);
+ float* data = NULL;
+ bool error = true;
+ if (!sndfile || !info->frames) {
+ lv2_log_error(logger, "Failed to open %s\n", path);
+ } else if (info->channels != 1) {
+ lv2_log_error(logger, "%s has %d channels\n", path, info->channels);
+ } else if (!(data = (float*)malloc(sizeof(float) * info->frames))) {
+ lv2_log_error(logger, "Failed to allocate memory for sample\n");
+ } else {
+ error = false;
+ }
+
+ if (error) {
+ free(sample);
+ free(data);
+ sf_close(sndfile);
+ return NULL;
+ }
+
+ sf_seek(sndfile, 0ul, SEEK_SET);
+ sf_read_float(sndfile, data, info->frames);
+ sf_close(sndfile);
+
+ // Fill sample struct and return it
+ sample->data = data;
+ sample->path = (char*)malloc(path_len + 1);
+ sample->path_len = (uint32_t)path_len;
+ memcpy(sample->path, path, path_len + 1);
+
+ return sample;
+}
+
+static void
+free_sample(Sampler* self, Sample* sample)
+{
+ if (sample) {
+ lv2_log_trace(&self->logger, "Freeing %s\n", sample->path);
+ free(sample->path);
+ free(sample->data);
+ free(sample);
+ }
+}
+
+/**
+ Do work in a non-realtime thread.
+
+ This is called for every piece of work scheduled in the audio thread using
+ self->schedule->schedule_work(). A reply can be sent back to the audio
+ thread using the provided `respond` function.
+*/
+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* self = (Sampler*)instance;
+ const LV2_Atom* atom = (const LV2_Atom*)data;
+ if (atom->type == self->uris.eg_freeSample) {
+ // Free old sample
+ const SampleMessage* msg = (const SampleMessage*)data;
+ free_sample(self, msg->sample);
+ } else if (atom->type == self->forge.Object) {
+ // Handle set message (load sample).
+ const LV2_Atom_Object* obj = (const LV2_Atom_Object*)data;
+ const char* path = read_set_file(&self->uris, obj);
+ if (!path) {
+ lv2_log_error(&self->logger, "Malformed set file request\n");
+ return LV2_WORKER_ERR_UNKNOWN;
+ }
+
+ // Load sample.
+ Sample* sample = load_sample(&self->logger, path);
+ if (sample) {
+ // Send new sample to run() to be applied
+ respond(handle, sizeof(sample), &sample);
+ }
+ }
+
+ return LV2_WORKER_SUCCESS;
+}
+
+/**
+ Handle a response from work() in the audio thread.
+
+ When running normally, this will be called by the host after run(). When
+ freewheeling, this will be called immediately at the point the work was
+ scheduled.
+*/
+static LV2_Worker_Status
+work_response(LV2_Handle instance,
+ uint32_t size,
+ const void* data)
+{
+ Sampler* self = (Sampler*)instance;
+ Sample* old_sample = self->sample;
+ Sample* new_sample = *(Sample*const*)data;
+
+ // Install the new sample
+ self->sample = *(Sample*const*)data;
+
+ // Schedule work to free the old sample
+ SampleMessage msg = { { sizeof(Sample*), self->uris.eg_freeSample },
+ old_sample };
+ self->schedule->schedule_work(self->schedule->handle, sizeof(msg), &msg);
+
+ // 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,
+ new_sample->path,
+ new_sample->path_len);
+
+ return LV2_WORKER_SUCCESS;
+}
+
+static void
+connect_port(LV2_Handle instance,
+ uint32_t port,
+ void* data)
+{
+ Sampler* self = (Sampler*)instance;
+ switch (port) {
+ case SAMPLER_CONTROL:
+ self->control_port = (const LV2_Atom_Sequence*)data;
+ break;
+ case SAMPLER_NOTIFY:
+ self->notify_port = (LV2_Atom_Sequence*)data;
+ break;
+ case SAMPLER_OUT:
+ self->output_port = (float*)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.
+ Sampler* self = (Sampler*)calloc(1, sizeof(Sampler));
+ if (!self) {
+ return NULL;
+ }
+
+ // Get host features
+ const char* missing = lv2_features_query(
+ features,
+ LV2_LOG__log, &self->logger.log, false,
+ LV2_URID__map, &self->map, true,
+ LV2_WORKER__schedule, &self->schedule, true,
+ NULL);
+ lv2_log_logger_set_map(&self->logger, self->map);
+ if (missing) {
+ lv2_log_error(&self->logger, "Missing feature <%s>\n", missing);
+ free(self);
+ return NULL;
+ }
+
+ // Map URIs and initialise forge
+ map_sampler_uris(self->map, &self->uris);
+ lv2_atom_forge_init(&self->forge, self->map);
+ peaks_sender_init(&self->psend, self->map);
+
+ self->gain = 1.0;
+
+ return (LV2_Handle)self;
+}
+
+static void
+cleanup(LV2_Handle instance)
+{
+ Sampler* self = (Sampler*)instance;
+ free_sample(self, self->sample);
+ free(self);
+}
+
+static void
+activate(LV2_Handle instance)
+{
+ ((Sampler*)instance)->activated = true;
+}
+
+static void
+deactivate(LV2_Handle instance)
+{
+ ((Sampler*)instance)->activated = false;
+}
+
+/** Define a macro for converting a gain in dB to a coefficient. */
+#define DB_CO(g) ((g) > -90.0f ? powf(10.0f, (g) * 0.05f) : 0.0f)
+
+/**
+ Handle an incoming event in the audio thread.
+
+ This performs any actions triggered by an event, such as the start of sample
+ playback, a sample change, or responding to requests from the UI.
+*/
+static void
+handle_event(Sampler* self, LV2_Atom_Event* ev)
+{
+ SamplerURIs* uris = &self->uris;
+ PeaksURIs* peaks_uris = &self->psend.uris;
+
+ 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:
+ self->frame = 0;
+ self->play = true;
+ break;
+ default:
+ break;
+ }
+ } else if (lv2_atom_forge_is_object_type(&self->forge, ev->body.type)) {
+ const LV2_Atom_Object* obj = (const LV2_Atom_Object*)&ev->body;
+ if (obj->body.otype == uris->patch_Set) {
+ // Get the property and value of the set message
+ const LV2_Atom* property = NULL;
+ const LV2_Atom* value = NULL;
+ lv2_atom_object_get(obj,
+ uris->patch_property, &property,
+ uris->patch_value, &value,
+ 0);
+ if (!property) {
+ lv2_log_error(&self->logger, "Set message with no property\n");
+ return;
+ } else if (property->type != uris->atom_URID) {
+ lv2_log_error(&self->logger, "Set property is not a URID\n");
+ return;
+ }
+
+ const uint32_t key = ((const LV2_Atom_URID*)property)->body;
+ if (key == uris->eg_sample) {
+ // Sample change, send it to the worker.
+ lv2_log_trace(&self->logger, "Scheduling sample change\n");
+ self->schedule->schedule_work(self->schedule->handle,
+ lv2_atom_total_size(&ev->body),
+ &ev->body);
+ } else if (key == uris->param_gain) {
+ // Gain change
+ if (value->type == uris->atom_Float) {
+ self->gain = DB_CO(((LV2_Atom_Float*)value)->body);
+ }
+ }
+ } else if (obj->body.otype == uris->patch_Get && self->sample) {
+ const LV2_Atom_URID* accept = NULL;
+ const LV2_Atom_Int* n_peaks = NULL;
+ lv2_atom_object_get_typed(
+ obj,
+ uris->patch_accept, &accept, uris->atom_URID,
+ peaks_uris->peaks_total, &n_peaks, peaks_uris->atom_Int, 0);
+ if (accept && accept->body == peaks_uris->peaks_PeakUpdate) {
+ // Received a request for peaks, prepare for transmission
+ peaks_sender_start(&self->psend,
+ self->sample->data,
+ self->sample->info.frames,
+ n_peaks->body);
+ } else {
+ // Received a get message, emit our state (probably to UI)
+ lv2_atom_forge_frame_time(&self->forge, self->frame_offset);
+ write_set_file(&self->forge, &self->uris,
+ self->sample->path,
+ self->sample->path_len);
+ }
+ } else {
+ lv2_log_trace(&self->logger,
+ "Unknown object type %d\n", obj->body.otype);
+ }
+ } else {
+ lv2_log_trace(&self->logger,
+ "Unknown event type %d\n", ev->body.type);
+ }
+
+}
+
+/**
+ Output audio for a slice of the current cycle.
+*/
+static void
+render(Sampler* self, uint32_t start, uint32_t end)
+{
+ float* output = self->output_port;
+
+ if (self->play && self->sample) {
+ // Start/continue writing sample to output
+ for (; start < end; ++start) {
+ output[start] = self->sample->data[self->frame] * self->gain;
+ if (++self->frame == self->sample->info.frames) {
+ self->play = false; // Reached end of sample
+ break;
+ }
+ }
+ }
+
+ // Write silence to remaining buffer
+ for (; start < end; ++start) {
+ output[start] = 0.0f;
+ }
+}
+
+static void
+run(LV2_Handle instance, uint32_t sample_count)
+{
+ Sampler* self = (Sampler*)instance;
+
+ // Set up forge to write directly to notify output port.
+ const uint32_t notify_capacity = self->notify_port->atom.size;
+ lv2_atom_forge_set_buffer(&self->forge,
+ (uint8_t*)self->notify_port,
+ notify_capacity);
+
+ // Start a sequence in the notify output port.
+ lv2_atom_forge_sequence_head(&self->forge, &self->notify_frame, 0);
+
+ // Send update to UI if sample has changed due to state restore
+ if (self->sample_changed) {
+ lv2_atom_forge_frame_time(&self->forge, 0);
+ write_set_file(&self->forge, &self->uris,
+ self->sample->path,
+ self->sample->path_len);
+ self->sample_changed = false;
+ }
+
+ // Iterate over incoming events, emitting audio along the way
+ self->frame_offset = 0;
+ LV2_ATOM_SEQUENCE_FOREACH(self->control_port, ev) {
+ // Render output up to the time of this event
+ render(self, self->frame_offset, ev->time.frames);
+
+ /* Update current frame offset to this event's time. This is stored in
+ the instance because it is used for sychronous worker event
+ execution. This allows a sample load event to be executed with
+ sample accuracy when running in a non-realtime context (such as
+ exporting a session). */
+ self->frame_offset = ev->time.frames;
+
+ // Process this event
+ handle_event(self, ev);
+ }
+
+ // Use available space after any emitted events to send peaks
+ peaks_sender_send(&self->psend, &self->forge, sample_count, self->frame_offset);
+
+ // Render output for the rest of the cycle past the last event
+ render(self, self->frame_offset, sample_count);
+}
+
+static LV2_State_Status
+save(LV2_Handle instance,
+ LV2_State_Store_Function store,
+ LV2_State_Handle handle,
+ uint32_t flags,
+ const LV2_Feature* const* features)
+{
+ Sampler* self = (Sampler*)instance;
+ if (!self->sample) {
+ return LV2_STATE_SUCCESS;
+ }
+
+ LV2_State_Map_Path* map_path = (LV2_State_Map_Path*)lv2_features_data(
+ features, LV2_STATE__mapPath);
+ if (!map_path) {
+ return LV2_STATE_ERR_NO_FEATURE;
+ }
+
+ // Map absolute sample path to an abstract state path
+ char* apath = map_path->abstract_path(map_path->handle, self->sample->path);
+
+ // Store eg:sample = abstract path
+ store(handle,
+ self->uris.eg_sample,
+ apath,
+ strlen(apath) + 1,
+ self->uris.atom_Path,
+ LV2_STATE_IS_POD | LV2_STATE_IS_PORTABLE);
+
+ free(apath);
+ return LV2_STATE_SUCCESS;
+}
+
+static LV2_State_Status
+restore(LV2_Handle instance,
+ LV2_State_Retrieve_Function retrieve,
+ LV2_State_Handle handle,
+ uint32_t flags,
+ const LV2_Feature* const* features)
+{
+ Sampler* self = (Sampler*)instance;
+
+ // Get host features
+ LV2_Worker_Schedule* schedule = NULL;
+ LV2_State_Map_Path* paths = NULL;
+ const char* missing = lv2_features_query(
+ features,
+ LV2_STATE__mapPath, &paths, true,
+ LV2_WORKER__schedule, &schedule, false,
+ NULL);
+ if (missing) {
+ lv2_log_error(&self->logger, "Missing feature <%s>\n", missing);
+ return LV2_STATE_ERR_NO_FEATURE;
+ }
+
+ // Get eg:sample from state
+ size_t size;
+ uint32_t type;
+ uint32_t valflags;
+ const void* value = retrieve(handle, self->uris.eg_sample,
+ &size, &type, &valflags);
+ if (!value) {
+ lv2_log_error(&self->logger, "Missing eg:sample\n");
+ return LV2_STATE_ERR_NO_PROPERTY;
+ } else if (type != self->uris.atom_Path) {
+ lv2_log_error(&self->logger, "Non-path eg:sample\n");
+ return LV2_STATE_ERR_BAD_TYPE;
+ }
+
+ // Map abstract state path to absolute path
+ const char* apath = (const char*)value;
+ char* path = paths->absolute_path(paths->handle, apath);
+
+ // Replace current sample with the new one
+ if (!self->activated || !schedule) {
+ // No scheduling available, load sample immediately
+ lv2_log_trace(&self->logger, "Synchronous restore\n");
+ Sample* sample = load_sample(&self->logger, path);
+ if (sample) {
+ free_sample(self, self->sample);
+ self->sample = sample;
+ self->sample_changed = true;
+ }
+ } else {
+ // Schedule sample to be loaded by the provided worker
+ lv2_log_trace(&self->logger, "Scheduling restore\n");
+ LV2_Atom_Forge forge;
+ LV2_Atom* buf = (LV2_Atom*)calloc(1, strlen(path) + 128);
+ lv2_atom_forge_init(&forge, self->map);
+ lv2_atom_forge_set_sink(&forge, atom_sink, atom_sink_deref, buf);
+ write_set_file(&forge, &self->uris, path, strlen(path));
+
+ const uint32_t msg_size = lv2_atom_pad_size(buf->size);
+ schedule->schedule_work(self->schedule->handle, msg_size, buf + 1);
+ free(buf);
+ }
+
+ free(path);
+
+ return LV2_STATE_SUCCESS;
+}
+
+static const void*
+extension_data(const char* uri)
+{
+ static const LV2_State_Interface state = { save, restore };
+ static const LV2_Worker_Interface worker = { work, work_response, NULL };
+ if (!strcmp(uri, LV2_STATE__interface)) {
+ return &state;
+ } else if (!strcmp(uri, LV2_WORKER__interface)) {
+ return &worker;
+ }
+ return NULL;
+}
+
+static const LV2_Descriptor descriptor = {
+ EG_SAMPLER_URI,
+ instantiate,
+ connect_port,
+ activate,
+ run,
+ deactivate,
+ cleanup,
+ extension_data
+};
+
+LV2_SYMBOL_EXPORT
+const LV2_Descriptor* lv2_descriptor(uint32_t index)
+{
+ switch (index) {
+ case 0:
+ return &descriptor;
+ default:
+ return NULL;
+ }
+}