text: /* Spa A2DP Sink
   *
   * 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 <unistd.h>
  #include <stddef.h>
  #include <stdio.h>
  #include <arpa/inet.h>
  #include <sys/ioctl.h>
  
  #include <spa/support/plugin.h>
  #include <spa/support/loop.h>
  #include <spa/support/log.h>
  #include <spa/support/system.h>
  #include <spa/utils/list.h>
  #include <spa/utils/keys.h>
  #include <spa/utils/names.h>
  #include <spa/utils/result.h>
  #include <spa/utils/string.h>
  #include <spa/monitor/device.h>
  
  #include <spa/node/node.h>
  #include <spa/node/utils.h>
  #include <spa/node/io.h>
  #include <spa/node/keys.h>
  #include <spa/param/param.h>
  #include <spa/param/latency-utils.h>
  #include <spa/param/audio/format.h>
  #include <spa/param/audio/format-utils.h>
  #include <spa/pod/filter.h>
  
  #include <sbc/sbc.h>
  
  #include "defs.h"
  #include "rtp.h"
  #include "a2dp-codecs.h"
  
  struct codec;
  
  struct props {
  	uint32_t min_latency;
  	uint32_t max_latency;
  	int64_t latency_offset;
  };
  
  #define FILL_FRAMES 2
  #define MAX_BUFFERS 32
  
  struct buffer {
  	uint32_t id;
  #define BUFFER_FLAG_OUT	(1<<0)
  	uint32_t flags;
  	struct spa_buffer *buf;
  	struct spa_meta_header *h;
  	struct spa_list link;
  };
  
  struct port {
  	struct spa_audio_info current_format;
  	uint32_t frame_size;
  	unsigned int have_format:1;
  
  	uint64_t info_all;
  	struct spa_port_info info;
  	struct spa_io_buffers *io;
  	struct spa_latency_info latency;
  #define IDX_EnumFormat	0
  #define IDX_Meta	1
  #define IDX_IO		2
  #define IDX_Format	3
  #define IDX_Buffers	4
  #define IDX_Latency	5
  #define N_PORT_PARAMS	6
  	struct spa_param_info params[N_PORT_PARAMS];
  
  	struct buffer buffers[MAX_BUFFERS];
  	uint32_t n_buffers;
  
  	struct spa_list free;
  	struct spa_list ready;
  
  	size_t ready_offset;
  };
  
  struct impl {
  	struct spa_handle handle;
  	struct spa_node node;
  
  	struct spa_log *log;
  	struct spa_loop *data_loop;
  	struct spa_system *data_system;
  
  	struct spa_hook_list hooks;
  	struct spa_callbacks callbacks;
  
  	uint64_t info_all;
  	struct spa_node_info info;
  #define IDX_PropInfo	0
  #define IDX_Props	1
  #define N_NODE_PARAMS	2
  	struct spa_param_info params[N_NODE_PARAMS];
  	struct props props;
  
  	struct spa_bt_transport *transport;
  	struct spa_hook transport_listener;
  
  	struct port port;
  
  	unsigned int started:1;
  	unsigned int following:1;
  
  	struct spa_source source;
  	int timerfd;
  	struct spa_source flush_source;
  
  	struct spa_io_clock *clock;
  	struct spa_io_position *position;
  
  	uint64_t current_time;
  	uint64_t next_time;
  	uint64_t last_error;
  
  	const struct a2dp_codec *codec;
  	bool codec_props_changed;
  	void *codec_props;
  	void *codec_data;
  	struct spa_audio_info codec_format;
  
  	int need_flush;
  	uint32_t block_size;
  	uint8_t buffer[4096];
  	uint32_t buffer_used;
  	uint32_t header_size;
  	uint32_t frame_count;
  	uint16_t seqnum;
  	uint32_t timestamp;
  	uint64_t sample_count;
  	uint8_t tmp_buffer[4096];
  	uint32_t tmp_buffer_used;
  	uint32_t fd_buffer_size;
  };
  
  #define NAME "a2dp-sink"
  
  #define CHECK_PORT(this,d,p)    ((d) == SPA_DIRECTION_INPUT && (p) == 0)
  
  static void reset_props(struct impl *this, struct props *props)
  {
  	if (this->codec->id == SPA_BLUETOOTH_AUDIO_CODEC_APTX_LL) {
  		props->min_latency = 256;
  	} else {
  		props->min_latency = MIN_LATENCY;
  	}
  	props->max_latency = MAX_LATENCY;
  	props->latency_offset = 0;
  }
  
  static int impl_node_enum_params(void *object, int seq,
  			uint32_t id, uint32_t start, uint32_t num,
  			const struct spa_pod *filter)
  {
  	struct impl *this = object;
  	struct spa_pod *param;
  	struct spa_pod_builder b = { 0 };
  	uint8_t buffer[1024];
  	struct spa_result_node_params result;
  	uint32_t count = 0, index_offset = 0;
  	bool enum_codec = false;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  	spa_return_val_if_fail(num != 0, -EINVAL);
  
  	result.id = id;
  	result.next = start;
        next:
  	result.index = result.next++;
  
  	spa_pod_builder_init(&b, buffer, sizeof(buffer));
  
  	switch (id) {
  	case SPA_PARAM_PropInfo:
  	{
  		struct props *p = &this->props;
  
  		switch (result.index) {
  		case 0:
  			param = spa_pod_builder_add_object(&b,
  				SPA_TYPE_OBJECT_PropInfo, id,
  				SPA_PROP_INFO_id,   SPA_POD_Id(SPA_PROP_minLatency),
  				SPA_PROP_INFO_name, SPA_POD_String("The minimum latency"),
  				SPA_PROP_INFO_type, SPA_POD_CHOICE_RANGE_Int(p->min_latency, 1, INT32_MAX));
  			break;
  		case 1:
  			param = spa_pod_builder_add_object(&b,
  				SPA_TYPE_OBJECT_PropInfo, id,
  				SPA_PROP_INFO_id,   SPA_POD_Id(SPA_PROP_maxLatency),
  				SPA_PROP_INFO_name, SPA_POD_String("The maximum latency"),
  				SPA_PROP_INFO_type, SPA_POD_CHOICE_RANGE_Int(p->max_latency, 1, INT32_MAX));
  			break;
  		case 2:
  			param = spa_pod_builder_add_object(&b,
  				SPA_TYPE_OBJECT_PropInfo, id,
  				SPA_PROP_INFO_id,   SPA_POD_Id(SPA_PROP_latencyOffsetNsec),
  				SPA_PROP_INFO_name, SPA_POD_String("Latency offset (ns)"),
  				SPA_PROP_INFO_type, SPA_POD_CHOICE_RANGE_Long(0, INT64_MIN, INT64_MAX));
  			break;
  		default:
  			enum_codec = true;
  			index_offset = 3;
  		}
  		break;
  	}
  	case SPA_PARAM_Props:
  	{
  		struct props *p = &this->props;
  
  		switch (result.index) {
  		case 0:
  			param = spa_pod_builder_add_object(&b,
  				SPA_TYPE_OBJECT_Props, id,
  				SPA_PROP_minLatency, SPA_POD_Int(p->min_latency),
  				SPA_PROP_maxLatency, SPA_POD_Int(p->max_latency),
  				SPA_PROP_latencyOffsetNsec, SPA_POD_Long(p->latency_offset));
  			break;
  		default:
  			enum_codec = true;
  			index_offset = 1;
  		}
  		break;
  	}
  	default:
  		return -ENOENT;
  	}
  
  	if (enum_codec) {
  		int res;
  		if (this->codec->enum_props == NULL || this->codec_props == NULL)
  			return 0;
  		else if ((res = this->codec->enum_props(this->codec_props,
  					this->transport->device->settings,
  					id, result.index - index_offset, &b, &param)) != 1)
  			return res;
  	}
  
  	if (spa_pod_filter(&b, &result.param, param, filter) < 0)
  		goto next;
  
  	spa_node_emit_result(&this->hooks, seq, 0, SPA_RESULT_TYPE_NODE_PARAMS, &result);
  
  	if (++count != num)
  		goto next;
  
  	return 0;
  }
  
  static int set_timeout(struct impl *this, uint64_t time)
  {
  	struct itimerspec ts;
  	ts.it_value.tv_sec = time / SPA_NSEC_PER_SEC;
  	ts.it_value.tv_nsec = time % SPA_NSEC_PER_SEC;
  	ts.it_interval.tv_sec = 0;
  	ts.it_interval.tv_nsec = 0;
  	return spa_system_timerfd_settime(this->data_system,
  			this->timerfd, SPA_FD_TIMER_ABSTIME, &ts, NULL);
  }
  
  static int set_timers(struct impl *this)
  {
  	struct timespec now;
  
  	spa_system_clock_gettime(this->data_system, CLOCK_MONOTONIC, &now);
  	this->next_time = SPA_TIMESPEC_TO_NSEC(&now);
  
  	return set_timeout(this, this->following ? 0 : this->next_time);
  }
  
  static int do_reassign_follower(struct spa_loop *loop,
  			bool async,
  			uint32_t seq,
  			const void *data,
  			size_t size,
  			void *user_data)
  {
  	struct impl *this = user_data;
  	set_timers(this);
  	return 0;
  }
  
  static inline bool is_following(struct impl *this)
  {
  	return this->position && this->clock && this->position->clock.id != this->clock->id;
  }
  
  static int impl_node_set_io(void *object, uint32_t id, void *data, size_t size)
  {
  	struct impl *this = object;
  	bool following;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	switch (id) {
  	case SPA_IO_Clock:
  		this->clock = data;
  		break;
  	case SPA_IO_Position:
  		this->position = data;
  		break;
  	default:
  		return -ENOENT;
  	}
  
  	following = is_following(this);
  	if (this->started && following != this->following) {
  		spa_log_debug(this->log, NAME " %p: reassign follower %d->%d", this, this->following, following);
  		this->following = following;
  		spa_loop_invoke(this->data_loop, do_reassign_follower, 0, NULL, 0, true, this);
  	}
  	return 0;
  }
  
  static void emit_node_info(struct impl *this, bool full);
  
  static void emit_port_info(struct impl *this, struct port *port, bool full);
  
  static void set_latency(struct impl *this, bool emit_latency)
  {
  	struct port *port = &this->port;
  	int64_t delay;
  
  	if (this->transport == NULL)
  		return;
  
  	delay = spa_bt_transport_get_delay_nsec(this->transport);
  	delay += SPA_CLAMP(this->props.latency_offset, -delay, INT64_MAX / 2);
  	port->latency.min_ns = port->latency.max_ns = delay;
  
  	if (emit_latency) {
  		port->info.change_mask |= SPA_PORT_CHANGE_MASK_PARAMS;
  		port->params[IDX_Latency].flags ^= SPA_PARAM_INFO_SERIAL;
  		emit_port_info(this, port, false);
  	}
  }
  
  static int apply_props(struct impl *this, const struct spa_pod *param)
  {
  	struct props new_props = this->props;
  	int changed = 0;
  
  	if (param == NULL) {
  		reset_props(this, &new_props);
  	} else {
  		spa_pod_parse_object(param,
  				SPA_TYPE_OBJECT_Props, NULL,
  				SPA_PROP_minLatency, SPA_POD_OPT_Int(&new_props.min_latency),
  				SPA_PROP_maxLatency, SPA_POD_OPT_Int(&new_props.max_latency),
  				SPA_PROP_latencyOffsetNsec, SPA_POD_OPT_Long(&new_props.latency_offset));
  	}
  
  	changed = (memcmp(&new_props, &this->props, sizeof(struct props)) != 0);
  	this->props = new_props;
  
  	if (changed)
  		set_latency(this, true);
  
  	return changed;
  }
  
  static int impl_node_set_param(void *object, uint32_t id, uint32_t flags,
  			       const struct spa_pod *param)
  {
  	struct impl *this = object;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	switch (id) {
  	case SPA_PARAM_Props:
  	{
  		int res, codec_res = 0;
  		res = apply_props(this, param);
  		if (this->codec_props && this->codec->set_props) {
  			codec_res = this->codec->set_props(this->codec_props, param);
  			if (codec_res > 0)
  				this->codec_props_changed = true;
  		}
  		if (res > 0 || codec_res > 0) {
  			this->info.change_mask |= SPA_NODE_CHANGE_MASK_PARAMS;
  			this->params[IDX_Props].flags ^= SPA_PARAM_INFO_SERIAL;
  			emit_node_info(this, false);
  		}
  		break;
  	}
  	default:
  		return -ENOENT;
  	}
  
  	return 0;
  }
  
  static int reset_buffer(struct impl *this)
  {
  	if (this->codec_props_changed && this->codec_props
  			&& this->codec->update_props) {
  		this->codec->update_props(this->codec_data, this->codec_props);
  		this->codec_props_changed = false;
  	}
  	this->need_flush = 0;
  	this->frame_count = 0;
  	this->buffer_used = this->codec->start_encode(this->codec_data,
  			this->buffer, sizeof(this->buffer),
  			this->seqnum++, this->timestamp);
  	this->header_size = this->buffer_used;
  	this->timestamp = this->sample_count;
  	return 0;
  }
  
  static int get_transport_unused_size(struct impl *this)
  {
  	int res, value;
  	res = ioctl(this->flush_source.fd, TIOCOUTQ, &value);
  	if (res < 0) {
  		spa_log_error(this->log, NAME " %p: ioctl fail: %m", this);
  		return -errno;
  	}
  	spa_log_trace(this->log, NAME " %p: fd unused buffer size:%d/%d", this, value, this->fd_buffer_size);
  	return value;
  }
  
  static int send_buffer(struct impl *this)
  {
  	int written, unsent;
  	unsent = get_transport_unused_size(this);
  	if (unsent >= 0) {
  		unsent = this->fd_buffer_size - unsent;
  		this->codec->abr_process(this->codec_data, unsent);
  	}
  
  	spa_log_trace(this->log, NAME " %p: send %d %u %u %u %u",
  			this, this->frame_count, this->block_size, this->seqnum,
  			this->timestamp, this->buffer_used);
  
  	written = send(this->flush_source.fd, this->buffer,
  			this->buffer_used, MSG_DONTWAIT | MSG_NOSIGNAL);
  
  	spa_log_trace(this->log, NAME " %p: send %d", this, written);
  
  	if (written < 0) {
  		spa_log_debug(this->log, NAME " %p: %m", this);
  		return -errno;
  	}
  
  	return written;
  }
  
  static bool want_flush(struct impl *this)
  {
  	return (this->frame_count * this->block_size / this->port.frame_size >= this->props.min_latency);
  }
  
  static int encode_buffer(struct impl *this, const void *data, uint32_t size)
  {
  	int processed;
  	size_t out_encoded;
  	struct port *port = &this->port;
  	const void *from_data = data;
  	int from_size = size;
  
  	spa_log_trace(this->log, NAME " %p: encode %d used %d, %d %d %d",
  			this, size, this->buffer_used, port->frame_size, this->block_size,
  			this->frame_count);
  
  	if (this->need_flush)
  		return 0;
  
  	if (this->buffer_used >= sizeof(this->buffer))
  		return -ENOSPC;
  
  	if (size < this->block_size - this->tmp_buffer_used) {
  		memcpy(this->tmp_buffer + this->tmp_buffer_used, data, size);
  		this->tmp_buffer_used += size;
  		return size;
  	} else if (this->tmp_buffer_used > 0) {
  		memcpy(this->tmp_buffer + this->tmp_buffer_used, data, this->block_size - this->tmp_buffer_used);
  		from_data = this->tmp_buffer;
  		from_size = this->block_size;
  		this->tmp_buffer_used = this->block_size - this->tmp_buffer_used;
  	}
  
  	processed = this->codec->encode(this->codec_data,
  				from_data, from_size,
  				this->buffer + this->buffer_used,
  				sizeof(this->buffer) - this->buffer_used,
  				&out_encoded, &this->need_flush);
  	if (processed < 0)
  		return processed;
  
  	this->sample_count += processed / port->frame_size;
  	this->frame_count += processed / this->block_size;
  	this->buffer_used += out_encoded;
  
  	spa_log_trace(this->log, NAME " %p: processed %d %zd used %d",
  			this, processed, out_encoded, this->buffer_used);
  
  	if (this->tmp_buffer_used) {
  		processed = this->tmp_buffer_used;
  		this->tmp_buffer_used = 0;
  	}
  	return processed;
  }
  
  static int flush_buffer(struct impl *this)
  {
  	spa_log_trace(this->log, NAME" %p: used:%d block_size:%d", this,
  			this->buffer_used, this->block_size);
  
  	if (this->need_flush || want_flush(this))
  		return send_buffer(this);
  
  	return 0;
  }
  
  static int add_data(struct impl *this, const void *data, uint32_t size)
  {
  	int processed, total = 0;
  
  	while (size > 0) {
  		processed = encode_buffer(this, data, size);
  
  		if (processed <= 0)
  			return total > 0 ? total : processed;
  
  		data = SPA_PTROFF(data, processed, void);
  		size -= processed;
  		total += processed;
  	}
  	return total;
  }
  
  static void enable_flush(struct impl *this, bool enabled)
  {
  	if (SPA_FLAG_IS_SET(this->flush_source.mask, SPA_IO_OUT) != enabled) {
  		SPA_FLAG_UPDATE(this->flush_source.mask, SPA_IO_OUT, enabled);
  		spa_loop_update_source(this->data_loop, &this->flush_source);
  	}
  }
  
  static int flush_data(struct impl *this, uint64_t now_time)
  {
  	int written;
  	uint32_t total_frames;
  	struct port *port = &this->port;
  
  	total_frames = 0;
  again:
  	written = 0;
  	while (!spa_list_is_empty(&port->ready) && !this->need_flush) {
  		uint8_t *src;
  		uint32_t n_bytes, n_frames;
  		struct buffer *b;
  		struct spa_data *d;
  		uint32_t index, offs, avail, l0, l1;
  
  		b = spa_list_first(&port->ready, struct buffer, link);
  		d = b->buf->datas;
  
  		src = d[0].data;
  
  		index = d[0].chunk->offset + port->ready_offset;
  		avail = d[0].chunk->size - port->ready_offset;
  		avail /= port->frame_size;
  
  		offs = index % d[0].maxsize;
  		n_frames = avail;
  		n_bytes = n_frames * port->frame_size;
  
  		l0 = SPA_MIN(n_bytes, d[0].maxsize - offs);
  		l1 = n_bytes - l0;
  
  		written = add_data(this, src + offs, l0);
  		if (written > 0 && l1 > 0)
  			written += add_data(this, src, l1);
  		if (written <= 0) {
  			if (written < 0 && written != -ENOSPC) {
  				spa_list_remove(&b->link);
  				SPA_FLAG_SET(b->flags, BUFFER_FLAG_OUT);
  				this->port.io->buffer_id = b->id;
  				spa_log_warn(this->log, NAME " %p: error %s, reuse buffer %u",
  						this, spa_strerror(written), b->id);
  				spa_node_call_reuse_buffer(&this->callbacks, 0, b->id);
  				port->ready_offset = 0;
  			}
  			break;
  		}
  
  		n_frames = written / port->frame_size;
  
  		port->ready_offset += written;
  
  		if (port->ready_offset >= d[0].chunk->size) {
  			spa_list_remove(&b->link);
  			SPA_FLAG_SET(b->flags, BUFFER_FLAG_OUT);
  			spa_log_trace(this->log, NAME " %p: reuse buffer %u", this, b->id);
  			this->port.io->buffer_id = b->id;
  
  			spa_node_call_reuse_buffer(&this->callbacks, 0, b->id);
  			port->ready_offset = 0;
  		}
  		total_frames += n_frames;
  
  		spa_log_trace(this->log, NAME " %p: written %u frames", this, total_frames);
  	}
  
  	if (written > 0 && this->buffer_used == this->header_size) {
  		enable_flush(this, false);
  		return 0;
  	}
  
  	written = flush_buffer(this);
  	if (written == -EAGAIN) {
  		spa_log_trace(this->log, NAME" %p: delay flush", this);
  		if (now_time - this->last_error > SPA_NSEC_PER_SEC / 2) {
  			this->codec->reduce_bitpool(this->codec_data);
  			this->last_error = now_time;
  		}
  		this->need_flush = true;
  		enable_flush(this, true);
  	}
  	else if (written < 0) {
  		spa_log_trace(this->log, NAME" %p: error flushing %s", this,
  				spa_strerror(written));
  		reset_buffer(this);
  		enable_flush(this, false);
  		return written;
  	}
  	else if (written > 0) {
  		reset_buffer(this);
  		if (now_time - this->last_error > SPA_NSEC_PER_SEC) {
  			this->codec->increase_bitpool(this->codec_data);
  			this->last_error = now_time;
  		}
  		if (!spa_list_is_empty(&port->ready))
  			goto again;
  
  		enable_flush(this, false);
  	}
  	else {
  		/* Don't want to flush yet, or failed to write anything */
  		spa_log_trace(this->log, NAME" %p: skip flush", this);
  		enable_flush(this, false);
  	}
  	return 0;
  }
  
  static void a2dp_on_flush(struct spa_source *source)
  {
  	struct impl *this = source->data;
  
  	spa_log_trace(this->log, NAME" %p: flushing", this);
  
  	if (!SPA_FLAG_IS_SET(source->rmask, SPA_IO_OUT)) {
  		spa_log_warn(this->log, NAME" %p: error %d", this, source->rmask);
  		if (this->flush_source.loop)
  			spa_loop_remove_source(this->data_loop, &this->flush_source);
  		return;
  	}
  	flush_data(this, this->current_time);
  }
  
  static void a2dp_on_timeout(struct spa_source *source)
  {
  	struct impl *this = source->data;
  	struct port *port = &this->port;
  	uint64_t exp, duration;
  	uint32_t rate;
  	struct spa_io_buffers *io = port->io;
  	uint64_t prev_time, now_time;
  
  	if (this->transport == NULL)
  		return;
  
  	if (this->started && spa_system_timerfd_read(this->data_system, this->timerfd, &exp) < 0)
  		spa_log_warn(this->log, "error reading timerfd: %s", strerror(errno));
  
  	prev_time = this->current_time;
  	now_time = this->current_time = this->next_time;
  
  	spa_log_debug(this->log, NAME" %p: timeout %"PRIu64" %"PRIu64"", this,
  			now_time, now_time - prev_time);
  
  	if (SPA_LIKELY(this->position)) {
  		duration = this->position->clock.duration;
  		rate = this->position->clock.rate.denom;
  	} else {
  		duration = 1024;
  		rate = 48000;
  	}
  
  	this->next_time = now_time + duration * SPA_NSEC_PER_SEC / rate;
  
  	if (SPA_LIKELY(this->clock)) {
  		int64_t delay_nsec;
  
  		this->clock->nsec = now_time;
  		this->clock->position += duration;
  		this->clock->duration = duration;
  		this->clock->rate_diff = 1.0f;
  		this->clock->next_nsec = this->next_time;
  
  		delay_nsec = spa_bt_transport_get_delay_nsec(this->transport);
  
  		/* Negative delay doesn't work properly, so disallow it */
  		delay_nsec += SPA_CLAMP(this->props.latency_offset, -delay_nsec, INT64_MAX / 2);
  
  		this->clock->delay = (delay_nsec * this->clock->rate.denom) / SPA_NSEC_PER_SEC;
  	}
  
  
  	spa_log_trace(this->log, NAME " %p: %d", this, io->status);
  	io->status = SPA_STATUS_NEED_DATA;
  	spa_node_call_ready(&this->callbacks, SPA_STATUS_NEED_DATA);
  
  	set_timeout(this, this->next_time);
  }
  
  static int do_start(struct impl *this)
  {
  	int i, res, val, size;
  	struct port *port;
  	socklen_t len;
  	uint8_t *conf;
  
  	if (this->started)
  		return 0;
  
  	spa_return_val_if_fail(this->transport, -EIO);
  
  	this->following = is_following(this);
  
          spa_log_debug(this->log, NAME " %p: start following:%d", this, this->following);
  
  	if ((res = spa_bt_transport_acquire(this->transport, false)) < 0)
  		return res;
  
  	port = &this->port;
  
  	conf = this->transport->configuration;
  	size = this->transport->configuration_len;
  
  	for (i = 0; i < size; i++)
  		spa_log_debug(this->log, "  %d: %02x", i, conf[i]);
  
  	this->codec_data = this->codec->init(this->codec, 0,
  			this->transport->configuration,
  			this->transport->configuration_len,
  			&port->current_format,
  			this->codec_props,
  			this->transport->write_mtu);
  	if (this->codec_data == NULL)
  		return -EIO;
  
          spa_log_info(this->log, NAME " %p: using A2DP codec %s, delay:%"PRIi64" ms", this, this->codec->description,
                       (int64_t)(spa_bt_transport_get_delay_nsec(this->transport) / SPA_NSEC_PER_MSEC));
  
  	this->seqnum = 0;
  
  	this->block_size = this->codec->get_block_size(this->codec_data);
  	if (this->block_size > sizeof(this->tmp_buffer)) {
  		spa_log_error(this->log, "block-size %d > %zu",
  				this->block_size, sizeof(this->tmp_buffer));
  		return -EIO;
  	}
  
          spa_log_debug(this->log, NAME " %p: block_size %d", this,
  			this->block_size);
  
  	val = this->codec->send_buf_size > 0
  			/* The kernel doubles the SO_SNDBUF option value set by setsockopt(). */
  			? this->codec->send_buf_size / 2 + this->codec->send_buf_size % 2
  			: FILL_FRAMES * this->transport->write_mtu;
  	if (setsockopt(this->transport->fd, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)) < 0)
  		spa_log_warn(this->log, NAME " %p: SO_SNDBUF %m", this);
  
  	len = sizeof(val);
  	if (getsockopt(this->transport->fd, SOL_SOCKET, SO_SNDBUF, &val, &len) < 0) {
  		spa_log_warn(this->log, NAME " %p: SO_SNDBUF %m", this);
  	}
  	else {
  		spa_log_debug(this->log, NAME " %p: SO_SNDBUF: %d", this, val);
  	}
  	this->fd_buffer_size = val;
  
  	val = FILL_FRAMES * this->transport->read_mtu;
  	if (setsockopt(this->transport->fd, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)) < 0)
  		spa_log_warn(this->log, NAME " %p: SO_RCVBUF %m", this);
  
  	val = 6;
  	if (setsockopt(this->transport->fd, SOL_SOCKET, SO_PRIORITY, &val, sizeof(val)) < 0)
  		spa_log_warn(this->log, "SO_PRIORITY failed: %m");
  
  	reset_buffer(this);
  
  	this->source.data = this;
  	this->source.fd = this->timerfd;
  	this->source.func = a2dp_on_timeout;
  	this->source.mask = SPA_IO_IN;
  	this->source.rmask = 0;
  	spa_loop_add_source(this->data_loop, &this->source);
  
  	this->flush_source.data = this;
  	this->flush_source.fd = this->transport->fd;
  	this->flush_source.func = a2dp_on_flush;
  	this->flush_source.mask = 0;
  	this->flush_source.rmask = 0;
  	spa_loop_add_source(this->data_loop, &this->flush_source);
  
  	set_timers(this);
  	this->started = true;
  
  	return 0;
  }
  
  static int do_remove_source(struct spa_loop *loop,
  			    bool async,
  			    uint32_t seq,
  			    const void *data,
  			    size_t size,
  			    void *user_data)
  {
  	struct impl *this = user_data;
  	struct itimerspec ts;
  
  	if (this->source.loop)
  		spa_loop_remove_source(this->data_loop, &this->source);
  	ts.it_value.tv_sec = 0;
  	ts.it_value.tv_nsec = 0;
  	ts.it_interval.tv_sec = 0;
  	ts.it_interval.tv_nsec = 0;
  	spa_system_timerfd_settime(this->data_system, this->timerfd, 0, &ts, NULL);
  	if (this->flush_source.loop)
  		spa_loop_remove_source(this->data_loop, &this->flush_source);
  
  	return 0;
  }
  
  static int do_stop(struct impl *this)
  {
  	int res = 0;
  
  	if (!this->started)
  		return 0;
  
          spa_log_trace(this->log, NAME " %p: stop", this);
  
  	spa_loop_invoke(this->data_loop, do_remove_source, 0, NULL, 0, true, this);
  
  	this->started = false;
  
  	if (this->transport)
  		res = spa_bt_transport_release(this->transport);
  
  	if (this->codec_data)
  		this->codec->deinit(this->codec_data);
  	this->codec_data = NULL;
  
  	return res;
  }
  
  static int impl_node_send_command(void *object, const struct spa_command *command)
  {
  	struct impl *this = object;
  	struct port *port;
  	int res;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  	spa_return_val_if_fail(command != NULL, -EINVAL);
  
  	port = &this->port;
  
  	switch (SPA_NODE_COMMAND_ID(command)) {
  	case SPA_NODE_COMMAND_Start:
  		if (!port->have_format)
  			return -EIO;
  		if (port->n_buffers == 0)
  			return -EIO;
  
  		if ((res = do_start(this)) < 0)
  			return res;
  		break;
  	case SPA_NODE_COMMAND_Suspend:
  	case SPA_NODE_COMMAND_Pause:
  		if ((res = do_stop(this)) < 0)
  			return res;
  		break;
  	default:
  		return -ENOTSUP;
  	}
  	return 0;
  }
  
  static void emit_node_info(struct impl *this, bool full)
  {
  	char latency[64] = SPA_STRINGIFY(MIN_LATENCY)"/48000";
  	struct spa_dict_item node_info_items[] = {
  		{ SPA_KEY_DEVICE_API, "bluez5" },
  		{ SPA_KEY_MEDIA_CLASS, "Audio/Sink" },
  		{ SPA_KEY_NODE_DRIVER, "true" },
  		{ SPA_KEY_NODE_LATENCY, latency },
  	};
  	uint64_t old = full ? this->info.change_mask : 0;
  	if (full)
  		this->info.change_mask = this->info_all;
  	if (this->info.change_mask) {
  		if (this->transport && this->port.have_format)
  			snprintf(latency, sizeof(latency), "%d/%d", (int)this->props.min_latency,
  					(int)this->port.current_format.info.raw.rate);
  		else
  			snprintf(latency, sizeof(latency), "%d/48000", (int)this->props.min_latency);
  		this->info.props = &SPA_DICT_INIT_ARRAY(node_info_items);
  		spa_node_emit_info(&this->hooks, &this->info);
  		this->info.change_mask = old;
  	}
  }
  
  static void emit_port_info(struct impl *this, struct port *port, bool full)
  {
  	uint64_t old = full ? port->info.change_mask : 0;
  	if (full)
  		port->info.change_mask = port->info_all;
  	if (port->info.change_mask) {
  		spa_node_emit_port_info(&this->hooks,
  				SPA_DIRECTION_INPUT, 0, &port->info);
  		port->info.change_mask = old;
  	}
  }
  
  static int
  impl_node_add_listener(void *object,
  		struct spa_hook *listener,
  		const struct spa_node_events *events,
  		void *data)
  {
  	struct impl *this = object;
  	struct spa_hook_list save;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	spa_hook_list_isolate(&this->hooks, &save, listener, events, data);
  
  	emit_node_info(this, true);
  	emit_port_info(this, &this->port, true);
  
  	spa_hook_list_join(&this->hooks, &save);
  
  	return 0;
  }
  
  static int
  impl_node_set_callbacks(void *object,
  			const struct spa_node_callbacks *callbacks,
  			void *data)
  {
  	struct impl *this = object;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	this->callbacks = SPA_CALLBACKS_INIT(callbacks, data);
  
  	return 0;
  }
  
  static int impl_node_sync(void *object, int seq)
  {
  	struct impl *this = object;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	spa_node_emit_result(&this->hooks, seq, 0, 0, NULL);
  
  	return 0;
  }
  
  static int impl_node_add_port(void *object, enum spa_direction direction, uint32_t port_id,
  		const struct spa_dict *props)
  {
  	return -ENOTSUP;
  }
  
  static int impl_node_remove_port(void *object, enum spa_direction direction, uint32_t port_id)
  {
  	return -ENOTSUP;
  }
  
  static int
  impl_node_port_enum_params(void *object, int seq,
  			enum spa_direction direction, uint32_t port_id,
  			uint32_t id, uint32_t start, uint32_t num,
  			const struct spa_pod *filter)
  {
  
  	struct impl *this = object;
  	struct port *port;
  	struct spa_pod *param;
  	struct spa_pod_builder b = { 0 };
  	uint8_t buffer[1024];
  	struct spa_result_node_params result;
  	uint32_t count = 0;
  	int res;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  	spa_return_val_if_fail(num != 0, -EINVAL);
  
  	spa_return_val_if_fail(CHECK_PORT(this, direction, port_id), -EINVAL);
  	port = &this->port;
  
  	result.id = id;
  	result.next = start;
        next:
  	result.index = result.next++;
  
  	spa_pod_builder_init(&b, buffer, sizeof(buffer));
  
  	switch (id) {
  	case SPA_PARAM_EnumFormat:
  		if (this->codec == NULL)
  			return -EIO;
  		if (this->transport == NULL)
  			return -EIO;
  
  		if ((res = this->codec->enum_config(this->codec,
  					this->transport->configuration,
  					this->transport->configuration_len,
  					id, result.index, &b, &param)) != 1)
  			return res;
  		break;
  
  	case SPA_PARAM_Format:
  		if (!port->have_format)
  			return -EIO;
  		if (result.index > 0)
  			return 0;
  
  		param = spa_format_audio_raw_build(&b, id, &port->current_format.info.raw);
  		break;
  
  	case SPA_PARAM_Buffers:
  		if (!port->have_format)
  			return -EIO;
  		if (result.index > 0)
  			return 0;
  
  		param = spa_pod_builder_add_object(&b,
  			SPA_TYPE_OBJECT_ParamBuffers, id,
  			SPA_PARAM_BUFFERS_buffers, SPA_POD_CHOICE_RANGE_Int(2, 2, MAX_BUFFERS),
  			SPA_PARAM_BUFFERS_blocks,  SPA_POD_Int(1),
  			SPA_PARAM_BUFFERS_size,    SPA_POD_CHOICE_RANGE_Int(
  							this->props.min_latency * port->frame_size,
  							this->props.min_latency * port->frame_size,
  							INT32_MAX),
  			SPA_PARAM_BUFFERS_stride,  SPA_POD_Int(port->frame_size),
  			SPA_PARAM_BUFFERS_align,   SPA_POD_Int(16));
  		break;
  
  	case SPA_PARAM_Meta:
  		switch (result.index) {
  		case 0:
  			param = spa_pod_builder_add_object(&b,
  				SPA_TYPE_OBJECT_ParamMeta, id,
  				SPA_PARAM_META_type, SPA_POD_Id(SPA_META_Header),
  				SPA_PARAM_META_size, SPA_POD_Int(sizeof(struct spa_meta_header)));
  			break;
  		default:
  			return 0;
  		}
  		break;
  
  	case SPA_PARAM_IO:
  		switch (result.index) {
  		case 0:
  			param = spa_pod_builder_add_object(&b,
  				SPA_TYPE_OBJECT_ParamIO, id,
  				SPA_PARAM_IO_id,   SPA_POD_Id(SPA_IO_Buffers),
  				SPA_PARAM_IO_size, SPA_POD_Int(sizeof(struct spa_io_buffers)));
  			break;
  		default:
  			return 0;
  		}
  		break;
  
  	case SPA_PARAM_Latency:
  		switch (result.index) {
  		case 0:
  			param = spa_latency_build(&b, id, &port->latency);
  			break;
  		default:
  			return 0;
  		}
  		break;
  
  	default:
  		return -ENOENT;
  	}
  
  	if (spa_pod_filter(&b, &result.param, param, filter) < 0)
  		goto next;
  
  	spa_node_emit_result(&this->hooks, seq, 0, SPA_RESULT_TYPE_NODE_PARAMS, &result);
  
  	if (++count != num)
  		goto next;
  
  	return 0;
  }
  
  static int clear_buffers(struct impl *this, struct port *port)
  {
  	do_stop(this);
  	if (port->n_buffers > 0) {
  		spa_list_init(&port->ready);
  		port->n_buffers = 0;
  	}
  	return 0;
  }
  
  static int port_set_format(struct impl *this, struct port *port,
  			   uint32_t flags,
  			   const struct spa_pod *format)
  {
  	int err;
  
  	if (format == NULL) {
  		spa_log_debug(this->log, "clear format");
  		clear_buffers(this, port);
  		port->have_format = false;
  	} else {
  		struct spa_audio_info info = { 0 };
  
  		if ((err = spa_format_parse(format, &info.media_type, &info.media_subtype)) < 0)
  			return err;
  
  		if (info.media_type != SPA_MEDIA_TYPE_audio ||
  		    info.media_subtype != SPA_MEDIA_SUBTYPE_raw)
  			return -EINVAL;
  
  		if (spa_format_audio_raw_parse(format, &info.info.raw) < 0)
  			return -EINVAL;
  
  		port->frame_size = info.info.raw.channels;
  		switch (info.info.raw.format) {
  		case SPA_AUDIO_FORMAT_S16:
  			port->frame_size *= 2;
  			break;
  		case SPA_AUDIO_FORMAT_S24:
  			port->frame_size *= 3;
  			break;
  		case SPA_AUDIO_FORMAT_S24_32:
  		case SPA_AUDIO_FORMAT_S32:
  		case SPA_AUDIO_FORMAT_F32:
  			port->frame_size *= 4;
  			break;
  		default:
  			return -EINVAL;
  		}
  
  		port->current_format = info;
  		port->have_format = true;
  	}
  
  	port->info.change_mask |= SPA_PORT_CHANGE_MASK_PARAMS;
  	if (port->have_format) {
  		port->info.change_mask |= SPA_PORT_CHANGE_MASK_FLAGS;
  		port->info.flags = SPA_PORT_FLAG_LIVE;
  		port->info.change_mask |= SPA_PORT_CHANGE_MASK_RATE;
  		port->info.rate = SPA_FRACTION(1, port->current_format.info.raw.rate);
  		port->params[IDX_Format] = SPA_PARAM_INFO(SPA_PARAM_Format, SPA_PARAM_INFO_READWRITE);
  		port->params[IDX_Buffers] = SPA_PARAM_INFO(SPA_PARAM_Buffers, SPA_PARAM_INFO_READ);
  		port->params[IDX_Latency].flags ^= SPA_PARAM_INFO_SERIAL;
  	} else {
  		port->params[IDX_Format] = SPA_PARAM_INFO(SPA_PARAM_Format, SPA_PARAM_INFO_WRITE);
  		port->params[IDX_Buffers] = SPA_PARAM_INFO(SPA_PARAM_Buffers, 0);
  	}
  	emit_port_info(this, port, false);
  
  	return 0;
  }
  
  static int
  impl_node_port_set_param(void *object,
  			 enum spa_direction direction, uint32_t port_id,
  			 uint32_t id, uint32_t flags,
  			 const struct spa_pod *param)
  {
  	struct impl *this = object;
  	struct port *port;
  	int res;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  	spa_return_val_if_fail(CHECK_PORT(node, direction, port_id), -EINVAL);
  	port = &this->port;
  
  	switch (id) {
  	case SPA_PARAM_Format:
  		res = port_set_format(this, port, flags, param);
  		break;
  	case SPA_PARAM_Latency:
  		res = 0;
  		break;
  	default:
  		res = -ENOENT;
  		break;
  	}
  	return res;
  }
  
  static int
  impl_node_port_use_buffers(void *object,
  		enum spa_direction direction, uint32_t port_id,
  		uint32_t flags,
  		struct spa_buffer **buffers, uint32_t n_buffers)
  {
  	struct impl *this = object;
  	struct port *port;
  	uint32_t i;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  	spa_return_val_if_fail(CHECK_PORT(this, direction, port_id), -EINVAL);
  	port = &this->port;
  
  	spa_log_debug(this->log, "use buffers %d", n_buffers);
  
  	if (!port->have_format)
  		return -EIO;
  
  	clear_buffers(this, port);
  
  	for (i = 0; i < n_buffers; i++) {
  		struct buffer *b = &port->buffers[i];
  
  		b->buf = buffers[i];
  		b->id = i;
  		SPA_FLAG_SET(b->flags, BUFFER_FLAG_OUT);
  
  		b->h = spa_buffer_find_meta_data(buffers[i], SPA_META_Header, sizeof(*b->h));
  
  		if (buffers[i]->datas[0].data == NULL) {
  			spa_log_error(this->log, NAME " %p: need mapped memory", this);
  			return -EINVAL;
  		}
  	}
  	port->n_buffers = n_buffers;
  
  	return 0;
  }
  
  static int
  impl_node_port_set_io(void *object,
  		      enum spa_direction direction,
  		      uint32_t port_id,
  		      uint32_t id,
  		      void *data, size_t size)
  {
  	struct impl *this = object;
  	struct port *port;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	spa_return_val_if_fail(CHECK_PORT(this, direction, port_id), -EINVAL);
  	port = &this->port;
  
  	switch (id) {
  	case SPA_IO_Buffers:
  		port->io = data;
  		break;
  	default:
  		return -ENOENT;
  	}
  	return 0;
  }
  
  static int impl_node_port_reuse_buffer(void *object, uint32_t port_id, uint32_t buffer_id)
  {
  	return -ENOTSUP;
  }
  
  static int impl_node_process(void *object)
  {
  	struct impl *this = object;
  	struct port *port;
  	struct spa_io_buffers *io;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	port = &this->port;
  	io = port->io;
  	spa_return_val_if_fail(io != NULL, -EIO);
  
  	if (io->status == SPA_STATUS_HAVE_DATA && io->buffer_id < port->n_buffers) {
  		struct buffer *b = &port->buffers[io->buffer_id];
  
  		if (!SPA_FLAG_IS_SET(b->flags, BUFFER_FLAG_OUT)) {
  			spa_log_warn(this->log, NAME " %p: buffer %u in use", this, io->buffer_id);
  			io->status = -EINVAL;
  			return -EINVAL;
  		}
  
  		spa_log_trace(this->log, NAME " %p: queue buffer %u", this, io->buffer_id);
  
  		spa_list_append(&port->ready, &b->link);
  		SPA_FLAG_CLEAR(b->flags, BUFFER_FLAG_OUT);
  
  		io->buffer_id = SPA_ID_INVALID;
  		io->status = SPA_STATUS_OK;
  	}
  	if (!spa_list_is_empty(&port->ready)) {
  		if (this->need_flush)
  			reset_buffer(this);
  		flush_data(this, this->current_time);
  	}
  
  	return SPA_STATUS_HAVE_DATA;
  }
  
  static const struct spa_node_methods impl_node = {
  	SPA_VERSION_NODE_METHODS,
  	.add_listener = impl_node_add_listener,
  	.set_callbacks = impl_node_set_callbacks,
  	.sync = impl_node_sync,
  	.enum_params = impl_node_enum_params,
  	.set_param = impl_node_set_param,
  	.set_io = impl_node_set_io,
  	.send_command = impl_node_send_command,
  	.add_port = impl_node_add_port,
  	.remove_port = impl_node_remove_port,
  	.port_enum_params = impl_node_port_enum_params,
  	.port_set_param = impl_node_port_set_param,
  	.port_use_buffers = impl_node_port_use_buffers,
  	.port_set_io = impl_node_port_set_io,
  	.port_reuse_buffer = impl_node_port_reuse_buffer,
  	.process = impl_node_process,
  };
  
  static void transport_delay_changed(void *data)
  {
  	struct impl *this = data;
  	spa_log_debug(this->log, "transport %p delay changed", this->transport);
  	set_latency(this, true);
  }
  
  static int do_transport_destroy(struct spa_loop *loop,
  				bool async,
  				uint32_t seq,
  				const void *data,
  				size_t size,
  				void *user_data)
  {
  	struct impl *this = user_data;
  	this->transport = NULL;
  	return 0;
  }
  
  static void transport_destroy(void *data)
  {
  	struct impl *this = data;
  	spa_log_debug(this->log, "transport %p destroy", this->transport);
  	spa_loop_invoke(this->data_loop, do_transport_destroy, 0, NULL, 0, true, this);
  }
  
  static const struct spa_bt_transport_events transport_events = {
  	SPA_VERSION_BT_TRANSPORT_EVENTS,
  	.delay_changed = transport_delay_changed,
  	.destroy = transport_destroy,
  };
  
  static int impl_get_interface(struct spa_handle *handle, const char *type, void **interface)
  {
  	struct impl *this;
  
  	spa_return_val_if_fail(handle != NULL, -EINVAL);
  	spa_return_val_if_fail(interface != NULL, -EINVAL);
  
  	this = (struct impl *) handle;
  
  	if (spa_streq(type, SPA_TYPE_INTERFACE_Node))
  		*interface = &this->node;
  	else
  		return -ENOENT;
  
  	return 0;
  }
  
  static int impl_clear(struct spa_handle *handle)
  {
  	struct impl *this = (struct impl *) handle;
  
  	if (this->codec_data)
  		this->codec->deinit(this->codec_data);
  	if (this->codec_props && this->codec->clear_props)
  		this->codec->clear_props(this->codec_props);
  	if (this->transport)
  		spa_hook_remove(&this->transport_listener);
  	spa_system_close(this->data_system, this->timerfd);
  	return 0;
  }
  
  static size_t
  impl_get_size(const struct spa_handle_factory *factory,
  	      const struct spa_dict *params)
  {
  	return sizeof(struct impl);
  }
  
  static int
  impl_init(const struct spa_handle_factory *factory,
  	  struct spa_handle *handle,
  	  const struct spa_dict *info,
  	  const struct spa_support *support,
  	  uint32_t n_support)
  {
  	struct impl *this;
  	struct port *port;
  	const char *str;
  
  	spa_return_val_if_fail(factory != NULL, -EINVAL);
  	spa_return_val_if_fail(handle != NULL, -EINVAL);
  
  	handle->get_interface = impl_get_interface;
  	handle->clear = impl_clear;
  
  	this = (struct impl *) handle;
  
  	this->log = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_Log);
  	this->data_loop = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_DataLoop);
  	this->data_system = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_DataSystem);
  
  	if (this->data_loop == NULL) {
  		spa_log_error(this->log, "a data loop is needed");
  		return -EINVAL;
  	}
  	if (this->data_system == NULL) {
  		spa_log_error(this->log, "a data system is needed");
  		return -EINVAL;
  	}
  
  	this->node.iface = SPA_INTERFACE_INIT(
  			SPA_TYPE_INTERFACE_Node,
  			SPA_VERSION_NODE,
  			&impl_node, this);
  	spa_hook_list_init(&this->hooks);
  
  	this->info_all = SPA_NODE_CHANGE_MASK_FLAGS |
  			SPA_NODE_CHANGE_MASK_PARAMS |
  			SPA_NODE_CHANGE_MASK_PROPS;
  	this->info = SPA_NODE_INFO_INIT();
  	this->info.max_input_ports = 1;
  	this->info.max_output_ports = 0;
  	this->info.flags = SPA_NODE_FLAG_RT;
  	this->params[IDX_PropInfo] = SPA_PARAM_INFO(SPA_PARAM_PropInfo, SPA_PARAM_INFO_READ);
  	this->params[IDX_Props] = SPA_PARAM_INFO(SPA_PARAM_Props, SPA_PARAM_INFO_READWRITE);
  	this->info.params = this->params;
  	this->info.n_params = N_NODE_PARAMS;
  
  	port = &this->port;
  	port->info_all = SPA_PORT_CHANGE_MASK_FLAGS |
  			SPA_PORT_CHANGE_MASK_PARAMS;
  	port->info = SPA_PORT_INFO_INIT();
  	port->info.flags = 0;
  	port->params[IDX_EnumFormat] = SPA_PARAM_INFO(SPA_PARAM_EnumFormat, SPA_PARAM_INFO_READ);
  	port->params[IDX_Meta] = SPA_PARAM_INFO(SPA_PARAM_Meta, SPA_PARAM_INFO_READ);
  	port->params[IDX_IO] = SPA_PARAM_INFO(SPA_PARAM_IO, SPA_PARAM_INFO_READ);
  	port->params[IDX_Format] = SPA_PARAM_INFO(SPA_PARAM_Format, SPA_PARAM_INFO_WRITE);
  	port->params[IDX_Buffers] = SPA_PARAM_INFO(SPA_PARAM_Buffers, 0);
  	port->params[IDX_Latency] = SPA_PARAM_INFO(SPA_PARAM_Latency, SPA_PARAM_INFO_READWRITE);
  	port->info.params = port->params;
  	port->info.n_params = N_PORT_PARAMS;
  
  	port->latency = SPA_LATENCY_INFO(SPA_DIRECTION_INPUT);
  	port->latency.min_quantum = 1.0f;
  	port->latency.max_quantum = 1.0f;
  	set_latency(this, false);
  
  	spa_list_init(&port->ready);
  
  	if (info && (str = spa_dict_lookup(info, SPA_KEY_API_BLUEZ5_TRANSPORT)))
  		sscanf(str, "pointer:%p", &this->transport);
  
  	if (this->transport == NULL) {
  		spa_log_error(this->log, "a transport is needed");
  		return -EINVAL;
  	}
  	if (this->transport->a2dp_codec == NULL) {
  		spa_log_error(this->log, "a transport codec is needed");
  		return -EINVAL;
  	}
  	this->codec = this->transport->a2dp_codec;
  	if (this->codec->init_props != NULL)
  		this->codec_props = this->codec->init_props(this->codec,
  					this->transport->device->settings);
  
  	reset_props(this, &this->props);
  
  	spa_bt_transport_add_listener(this->transport,
  			&this->transport_listener, &transport_events, this);
  
  	this->timerfd = spa_system_timerfd_create(this->data_system,
  			CLOCK_MONOTONIC, SPA_FD_CLOEXEC | SPA_FD_NONBLOCK);
  
  	return 0;
  }
  
  static const struct spa_interface_info impl_interfaces[] = {
  	{SPA_TYPE_INTERFACE_Node,},
  };
  
  static int
  impl_enum_interface_info(const struct spa_handle_factory *factory,
  			 const struct spa_interface_info **info, uint32_t *index)
  {
  	spa_return_val_if_fail(factory != NULL, -EINVAL);
  	spa_return_val_if_fail(info != NULL, -EINVAL);
  	spa_return_val_if_fail(index != NULL, -EINVAL);
  
  	switch (*index) {
  	case 0:
  		*info = &impl_interfaces[*index];
  		break;
  	default:
  		return 0;
  	}
  	(*index)++;
  	return 1;
  }
  
  static const struct spa_dict_item info_items[] = {
  	{ SPA_KEY_FACTORY_AUTHOR, "Wim Taymans <wim.taymans@gmail.com>" },
  	{ SPA_KEY_FACTORY_DESCRIPTION, "Play audio with the a2dp" },
  	{ SPA_KEY_FACTORY_USAGE, SPA_KEY_API_BLUEZ5_TRANSPORT"=<transport>" },
  };
  
  static const struct spa_dict info = SPA_DICT_INIT_ARRAY(info_items);
  
  const struct spa_handle_factory spa_a2dp_sink_factory = {
  	SPA_VERSION_HANDLE_FACTORY,
  	SPA_NAME_API_BLUEZ5_A2DP_SINK,
  	&info,
  	impl_get_size,
  	impl_init,
  	impl_enum_interface_info,
  };
  