text: /* Spa
   *
   * Copyright © 2018 Wim Taymans
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice (including the next
   * paragraph) shall be included in all copies or substantial portions of the
   * Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
   * DEALINGS IN THE SOFTWARE.
   */
  
  #include <math.h>
  #include <string.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <dlfcn.h>
  #include <errno.h>
  #include <pthread.h>
  #include <poll.h>
  
  #include <spa/support/plugin.h>
  #include <spa/support/log-impl.h>
  #include <spa/support/loop.h>
  #include <spa/node/node.h>
  #include <spa/node/io.h>
  #include <spa/node/utils.h>
  #include <spa/param/param.h>
  #include <spa/param/props.h>
  #include <spa/param/audio/format-utils.h>
  #include <spa/utils/names.h>
  #include <spa/utils/result.h>
  
  #define M_PI_M2 ( M_PI + M_PI )
  
  static SPA_LOG_IMPL(default_log);
  
  #define spa_debug(f,...) spa_log_trace(&default_log.log, f, __VA_ARGS__)
  
  #include <spa/graph/graph.h>
  
  #include <spa/debug/pod.h>
  
  struct buffer {
  	struct spa_buffer buffer;
  	struct spa_meta metas[1];
  	struct spa_meta_header header;
  	struct spa_data datas[1];
  	struct spa_chunk chunks[1];
  };
  
  struct data {
  	struct spa_log *log;
  	struct spa_system *system;
  	struct spa_loop *loop;
  	struct spa_loop_control *control;
  	struct spa_support support[5];
  	uint32_t n_support;
  
  	struct spa_graph graph;
  	struct spa_graph_state graph_state;
  	struct spa_graph_node source_node;
  	struct spa_graph_state source_state;
  	struct spa_graph_port source_out;
  	struct spa_graph_port sink_in;
  	struct spa_graph_node sink_node;
  	struct spa_graph_state sink_state;
  
  	struct spa_node *sink;
  
  	struct spa_node *source;
  	struct spa_io_buffers source_sink_io[1];
  	struct spa_buffer *source_buffers[1];
  	struct buffer source_buffer[1];
  
  	uint8_t ctrl[1024];
  	double freq_accum;
  	double volume_accum;
  
  	bool running;
  	pthread_t thread;
  };
  
  #define MIN_LATENCY     1024
  
  #define BUFFER_SIZE     4096
  
  static void
  init_buffer(struct data *data, struct spa_buffer **bufs, struct buffer *ba, int n_buffers,
  	    size_t size)
  {
  	int i;
  
  	for (i = 0; i < n_buffers; i++) {
  		struct buffer *b = &ba[i];
  		bufs[i] = &b->buffer;
  
  		b->buffer.metas = b->metas;
  		b->buffer.n_metas = 1;
  		b->buffer.datas = b->datas;
  		b->buffer.n_datas = 1;
  
  		b->header.flags = 0;
  		b->header.seq = 0;
  		b->header.pts = 0;
  		b->header.dts_offset = 0;
  		b->metas[0].type = SPA_META_Header;
  		b->metas[0].data = &b->header;
  		b->metas[0].size = sizeof(b->header);
  
  		b->datas[0].type = SPA_DATA_MemPtr;
  		b->datas[0].flags = 0;
  		b->datas[0].fd = -1;
  		b->datas[0].mapoffset = 0;
  		b->datas[0].maxsize = size;
  		b->datas[0].data = malloc(size);
  		b->datas[0].chunk = &b->chunks[0];
  		b->datas[0].chunk->offset = 0;
  		b->datas[0].chunk->size = 0;
  		b->datas[0].chunk->stride = 0;
  	}
  }
  
  static int make_node(struct data *data, struct spa_node **node, const char *lib, const char *name)
  {
  	struct spa_handle *handle;
  	int res;
  	void *hnd;
  	spa_handle_factory_enum_func_t enum_func;
  	uint32_t i;
  
  	if ((hnd = dlopen(lib, RTLD_NOW)) == NULL) {
  		printf("can't load %s: %s\n", lib, dlerror());
  		return -errno;
  	}
  	if ((enum_func = dlsym(hnd, SPA_HANDLE_FACTORY_ENUM_FUNC_NAME)) == NULL) {
  		printf("can't find enum function\n");
  		return -errno;
  	}
  
  	for (i = 0;;) {
  		const struct spa_handle_factory *factory;
  		void *iface;
  
  		if ((res = enum_func(&factory, &i)) <= 0) {
  			if (res != 0)
  				printf("can't enumerate factories: %s\n", spa_strerror(res));
  			break;
  		}
  		if (strcmp(factory->name, name))
  			continue;
  
  		handle = calloc(1, spa_handle_factory_get_size(factory, NULL));
  		if ((res =
  		     spa_handle_factory_init(factory, handle, NULL, data->support,
  					     data->n_support)) < 0) {
  			printf("can't make factory instance: %d\n", res);
  			return res;
  		}
  		if ((res = spa_handle_get_interface(handle, SPA_TYPE_INTERFACE_Node, &iface)) < 0) {
  			printf("can't get interface %d\n", res);
  			return res;
  		}
  		*node = iface;
  		return 0;
  	}
  	return -EBADF;
  }
  
  static void update_props(struct data *data)
  {
  	struct spa_pod_builder b;
  	struct spa_pod *pod;
  	struct spa_pod_frame f[2];
  
  	spa_pod_builder_init(&b, data->ctrl, sizeof(data->ctrl));
  
  #if 0
  	spa_pod_builder_push_sequence(&b, &f[0], 0);
  	spa_pod_builder_control(&b, 0, SPA_CONTROL_Properties);
  	spa_pod_builder_push_object(&b, &f[1], SPA_TYPE_OBJECT_Props, 0);
  	spa_pod_builder_prop(&b, SPA_PROP_frequency, 0);
  	spa_pod_builder_float(&b, ((sin(data->freq_accum) + 1.0) * 200.0) + 440.0);
  	spa_pod_builder_prop(&b, SPA_PROP_volume, 0);
  	spa_pod_builder_float(&b, (sin(data->volume_accum) / 2.0) + 0.5);
  	spa_pod_builder_pop(&b, &f[1]);
  	pod = spa_pod_builder_pop(&b, &f[0]);
  #else
  	spa_pod_builder_push_sequence(&b, &f[0], 0);
  	spa_pod_builder_control(&b, 0, SPA_CONTROL_Properties);
  	spa_pod_builder_add_object(&b,
  		SPA_TYPE_OBJECT_Props, 0,
  		SPA_PROP_frequency, SPA_POD_Float(((sin(data->freq_accum) + 1.0) * 200.0) + 440.0),
  		SPA_PROP_volume,    SPA_POD_Float((sin(data->volume_accum) / 2.0) + 0.5));
  	pod = spa_pod_builder_pop(&b, &f[0]);
  #endif
  
  	spa_debug_pod(0, NULL, pod);
  
  	data->freq_accum += M_PI_M2 / 880.0;
  	if (data->freq_accum >= M_PI_M2)
  		data->freq_accum -= M_PI_M2;
  
  	data->volume_accum += M_PI_M2 / 2000.0;
  	if (data->volume_accum >= M_PI_M2)
  		data->volume_accum -= M_PI_M2;
  }
  
  static int on_sink_ready(void *_data, int status)
  {
  	struct data *data = _data;
  
  	update_props(data);
  
  	spa_graph_node_process(&data->source_node);
  	spa_graph_node_process(&data->sink_node);
  	return 0;
  }
  
  static int
  on_sink_reuse_buffer(void *_data, uint32_t port_id, uint32_t buffer_id)
  {
  	struct data *data = _data;
  
  	data->source_sink_io[0].buffer_id = buffer_id;
  	return 0;
  }
  
  static const struct spa_node_callbacks sink_callbacks = {
  	SPA_VERSION_NODE_CALLBACKS,
  	.ready = on_sink_ready,
  	.reuse_buffer = on_sink_reuse_buffer
  };
  
  static int make_nodes(struct data *data, const char *device)
  {
  	int res;
  	struct spa_pod *props;
  	struct spa_pod_builder b = { 0 };
  	uint8_t buffer[512];
  	//uint32_t idx;
  
  	if ((res = make_node(data, &data->sink,
  			     "build/spa/plugins/alsa/libspa-alsa.so",
  			     SPA_NAME_API_ALSA_PCM_SINK)) < 0) {
  		printf("can't create alsa-sink: %d\n", res);
  		return res;
  	}
  	spa_node_set_callbacks(data->sink, &sink_callbacks, data);
  
  	spa_pod_builder_init(&b, buffer, sizeof(buffer));
  	props = spa_pod_builder_add_object(&b,
  		SPA_TYPE_OBJECT_Props, 0,
  		SPA_PROP_device,     SPA_POD_String(device ? device : "hw:0"),
  		SPA_PROP_minLatency, SPA_POD_Int(MIN_LATENCY));
  
  	spa_debug_pod(0, NULL, props);
  
  	if ((res = spa_node_set_param(data->sink, SPA_PARAM_Props, 0, props)) < 0)
  		printf("got set_props error %d\n", res);
  
  	if ((res = make_node(data, &data->source,
  			     "build/spa/plugins/audiotestsrc/libspa-audiotestsrc.so",
  			     "audiotestsrc")) < 0) {
  		printf("can't create audiotestsrc: %d\n", res);
  		return res;
  	}
  
  	spa_pod_builder_init(&b, buffer, sizeof(buffer));
  	props = spa_pod_builder_add_object(&b,
  		SPA_TYPE_OBJECT_Props, 0,
  		SPA_PROP_frequency, SPA_POD_Float(600.0),
  		SPA_PROP_volume,    SPA_POD_Float(0.5),
  		SPA_PROP_live,      SPA_POD_Bool(false));
  
  	if ((res = spa_node_set_param(data->source, SPA_PARAM_Props, 0, props)) < 0)
  		printf("got set_props error %d\n", res);
  
  	if ((res = spa_node_port_set_io(data->source,
  				     SPA_DIRECTION_OUTPUT, 0,
  				     SPA_IO_Control,
  				     &data->ctrl, sizeof(data->ctrl))) < 0) {
  		printf("can't set_io freq: %d\n", res);
  		return res;
  	}
  
  	data->source_sink_io[0] = SPA_IO_BUFFERS_INIT;
  
  	spa_node_port_set_io(data->source,
  			     SPA_DIRECTION_OUTPUT, 0,
  			     SPA_IO_Buffers,
  			     &data->source_sink_io[0], sizeof(data->source_sink_io[0]));
  	spa_node_port_set_io(data->sink,
  			     SPA_DIRECTION_INPUT, 0,
  			     SPA_IO_Buffers,
  			     &data->source_sink_io[0], sizeof(data->source_sink_io[0]));
  
  	spa_graph_node_init(&data->source_node, &data->source_state);
  	spa_graph_node_set_callbacks(&data->source_node, &spa_graph_node_impl_default, data->source);
  	spa_graph_node_add(&data->graph, &data->source_node);
  	spa_graph_port_init(&data->source_out, SPA_DIRECTION_OUTPUT, 0, 0);
  	spa_graph_port_add(&data->source_node, &data->source_out);
  
  	spa_graph_node_init(&data->sink_node, &data->sink_state);
  	spa_graph_node_set_callbacks(&data->sink_node, &spa_graph_node_impl_default, data->sink);
  	spa_graph_node_add(&data->graph, &data->sink_node);
  	spa_graph_port_init(&data->sink_in, SPA_DIRECTION_INPUT, 0, 0);
  	spa_graph_port_add(&data->sink_node, &data->sink_in);
  
  	spa_graph_port_link(&data->source_out, &data->sink_in);
  
  	return res;
  }
  
  static int negotiate_formats(struct data *data)
  {
  	int res;
  	struct spa_pod *format;
  	struct spa_pod_builder b = { 0 };
  	uint8_t buffer[4096];
  
  	spa_pod_builder_init(&b, buffer, sizeof(buffer));
  	format = spa_format_audio_raw_build(&b, 0,
  			&SPA_AUDIO_INFO_RAW_INIT(
  				.format = SPA_AUDIO_FORMAT_S16,
  				.rate = 48000,
  				.channels = 2 ));
  
  	if ((res = spa_node_port_set_param(data->sink,
  					   SPA_DIRECTION_INPUT, 0,
  					   SPA_PARAM_Format, 0, format)) < 0)
  		return res;
  
  	if ((res = spa_node_port_set_param(data->source,
  					   SPA_DIRECTION_OUTPUT, 0,
  					   SPA_PARAM_Format, 0, format)) < 0)
  		return res;
  
  	init_buffer(data, data->source_buffers, data->source_buffer, 1, BUFFER_SIZE);
  	if ((res =
  	     spa_node_port_use_buffers(data->sink,
  		     SPA_DIRECTION_INPUT, 0, 0,
  		     data->source_buffers, 1)) < 0)
  		return res;
  	if ((res =
  	     spa_node_port_use_buffers(data->source,
  		     SPA_DIRECTION_OUTPUT, 0, 0,
  		     data->source_buffers, 1)) < 0)
  		return res;
  
  	return 0;
  }
  
  static void *loop(void *user_data)
  {
  	struct data *data = user_data;
  
  	printf("enter thread\n");
  	spa_loop_control_enter(data->control);
  
  	while (data->running) {
  		spa_loop_control_iterate(data->control, -1);
  	}
  
  	printf("leave thread\n");
  	spa_loop_control_leave(data->control);
  
  	return NULL;
  }
  
  static void run_async_sink(struct data *data)
  {
  	int res, err;
  	struct spa_command cmd;
  
  	cmd = SPA_NODE_COMMAND_INIT(SPA_NODE_COMMAND_Start);
  	if ((res = spa_node_send_command(data->sink, &cmd)) < 0)
  		printf("got error %d\n", res);
  
  	spa_loop_control_leave(data->control);
  
  	data->running = true;
  	if ((err = pthread_create(&data->thread, NULL, loop, data)) != 0) {
  		printf("can't create thread: %d %s", err, strerror(err));
  		data->running = false;
  	}
  
  	printf("sleeping for 1000 seconds\n");
  	sleep(1000);
  
  	if (data->running) {
  		data->running = false;
  		pthread_join(data->thread, NULL);
  	}
  
  	spa_loop_control_enter(data->control);
  
  	cmd = SPA_NODE_COMMAND_INIT(SPA_NODE_COMMAND_Pause);
  	if ((res = spa_node_send_command(data->sink, &cmd)) < 0)
  		printf("got error %d\n", res);
  }
  
  static int load_handle(struct data *data, struct spa_handle **handle, const char *lib, const char *name)
  {
  	int res;
  	void *hnd;
  	spa_handle_factory_enum_func_t enum_func;
  	uint32_t i;
  
  	if ((hnd = dlopen(lib, RTLD_NOW)) == NULL) {
  		printf("can't load %s: %s\n", lib, dlerror());
  		return -errno;
  	}
  	if ((enum_func = dlsym(hnd, SPA_HANDLE_FACTORY_ENUM_FUNC_NAME)) == NULL) {
  		printf("can't find enum function\n");
  		return -errno;
  	}
  
  	for (i = 0;;) {
  		const struct spa_handle_factory *factory;
  
  		if ((res = enum_func(&factory, &i)) <= 0) {
  			if (res != 0)
  				printf("can't enumerate factories: %s\n", spa_strerror(res));
  			break;
  		}
  		if (strcmp(factory->name, name))
  			continue;
  
  		*handle = calloc(1, spa_handle_factory_get_size(factory, NULL));
  		if ((res = spa_handle_factory_init(factory, *handle,
  						NULL, data->support,
  						data->n_support)) < 0) {
  			printf("can't make factory instance: %d\n", res);
  			return res;
  		}
  		return 0;
  	}
  	return -EBADF;
  }
  
  int init_data(struct data *data)
  {
  	int res;
  	const char *str;
  	struct spa_handle *handle = NULL;
  	void *iface;
  
  	/* init the graph */
  	spa_graph_init(&data->graph, &data->graph_state);
  
  	/* set the default log */
  	data->log = &default_log.log;
  	data->support[data->n_support++] = SPA_SUPPORT_INIT(SPA_TYPE_INTERFACE_Log, data->log);
  
  	/* load and set support system */
  	if ((res = load_handle(data, &handle,
  					"build/spa/plugins/support/libspa-support.so",
  					SPA_NAME_SUPPORT_SYSTEM)) < 0)
  		return res;
  	if ((res = spa_handle_get_interface(handle, SPA_TYPE_INTERFACE_System, &iface)) < 0) {
  		printf("can't get System interface %d\n", res);
  		return res;
  	}
  	data->system = iface;
  	data->support[data->n_support++] = SPA_SUPPORT_INIT(SPA_TYPE_INTERFACE_System, data->system);
  	data->support[data->n_support++] = SPA_SUPPORT_INIT(SPA_TYPE_INTERFACE_DataSystem, data->system);
  
  	/* load and set support loop and loop control */
  	if ((res = load_handle(data, &handle,
  					"build/spa/plugins/support/libspa-support.so",
  					SPA_NAME_SUPPORT_LOOP)) < 0)
  		return res;
  
  	if ((res = spa_handle_get_interface(handle, SPA_TYPE_INTERFACE_Loop, &iface)) < 0) {
  		printf("can't get interface %d\n", res);
  		return res;
  	}
  	data->loop = iface;
  	data->support[data->n_support++] = SPA_SUPPORT_INIT(SPA_TYPE_INTERFACE_Loop, data->loop);
  	data->support[data->n_support++] = SPA_SUPPORT_INIT(SPA_TYPE_INTERFACE_DataLoop, data->loop);
  	if ((res = spa_handle_get_interface(handle, SPA_TYPE_INTERFACE_LoopControl, &iface)) < 0) {
  		printf("can't get interface %d\n", res);
  		return res;
  	}
  	data->control = iface;
  
  	if ((str = getenv("SPA_DEBUG")))
  		data->log->level = atoi(str);
  
  	return 0;
  }
  
  int main(int argc, char *argv[])
  {
  	struct data data = { NULL };
  	int res;
  
  	if ((res = init_data(&data)) < 0) {
  		printf("can't init data: %d (%s)\n", res, spa_strerror(res));
  		return -1;
  	}
  
  	if ((res = make_nodes(&data, argc > 1 ? argv[1] : NULL)) < 0) {
  		printf("can't make nodes: %d (%s)\n", res, spa_strerror(res));
  		return -1;
  	}
  	if ((res = negotiate_formats(&data)) < 0) {
  		printf("can't negotiate nodes: %d (%s)\n", res, spa_strerror(res));
  		return -1;
  	}
  
  	spa_loop_control_enter(data.control);
  	run_async_sink(&data);
  	spa_loop_control_leave(data.control);
  
  	return 0;
  }
  