/* * Copyright (C) 2016 BlueKitchen GmbH * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the copyright holders nor the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * 4. Any redistribution, use, or modification is done solely for * personal benefit and not for any commercial purpose or for * monetary gain. * * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * Please inquire about commercial licensing options at * contact@bluekitchen-gmbh.com * */ #define __BTSTACK_FILE__ "a2dp_source.c" #include #include #include #include #include #include "btstack.h" #include "avdtp.h" #include "avdtp_util.h" #include "avdtp_source.h" #include "a2dp_source.h" #include "sbc_encoder.h" static const char * default_a2dp_source_service_name = "BTstack A2DP Source Service"; static const char * default_a2dp_source_service_provider_name = "BTstack A2DP Source Service Provider"; static avdtp_context_t a2dp_source_context; typedef struct { // to app uint32_t fill_audio_ring_buffer_timeout_ms; uint32_t time_audio_data_sent; // ms uint32_t acc_num_missed_samples; uint32_t samples_ready; btstack_timer_source_t fill_audio_ring_buffer_timer; btstack_ring_buffer_t sbc_ring_buffer; btstack_sbc_encoder_state_t sbc_encoder_state; int reconfigure; int num_channels; int sampling_frequency; int channel_mode; int block_length; int subbands; int allocation_method; int min_bitpool_value; int max_bitpool_value; avdtp_stream_endpoint_t * local_stream_endpoint; avdtp_sep_t * active_remote_sep; } avdtp_stream_endpoint_context_t; static a2dp_state_t app_state = A2DP_IDLE; static avdtp_stream_endpoint_context_t sc; static uint16_t avdtp_cid = 0; static int next_remote_sep_index_to_query = 0; static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); void a2dp_source_create_sdp_record(uint8_t * service, uint32_t service_record_handle, uint16_t supported_features, const char * service_name, const char * service_provider_name){ uint8_t* attribute; de_create_sequence(service); // 0x0000 "Service Record Handle" de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_RECORD_HANDLE); de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle); // 0x0001 "Service Class ID List" de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST); attribute = de_push_sequence(service); { de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_AUDIO_SOURCE); } de_pop_sequence(service, attribute); // 0x0004 "Protocol Descriptor List" de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST); attribute = de_push_sequence(service); { uint8_t* l2cpProtocol = de_push_sequence(attribute); { de_add_number(l2cpProtocol, DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_L2CAP); de_add_number(l2cpProtocol, DE_UINT, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP); } de_pop_sequence(attribute, l2cpProtocol); uint8_t* avProtocol = de_push_sequence(attribute); { de_add_number(avProtocol, DE_UUID, DE_SIZE_16, BLUETOOTH_PROTOCOL_AVDTP); // avProtocol_service de_add_number(avProtocol, DE_UINT, DE_SIZE_16, 0x0103); // version } de_pop_sequence(attribute, avProtocol); } de_pop_sequence(service, attribute); // 0x0005 "Public Browse Group" de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BROWSE_GROUP_LIST); // public browse group attribute = de_push_sequence(service); { de_add_number(attribute, DE_UUID, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_PUBLIC_BROWSE_ROOT); } de_pop_sequence(service, attribute); // 0x0009 "Bluetooth Profile Descriptor List" de_add_number(service, DE_UINT, DE_SIZE_16, BLUETOOTH_ATTRIBUTE_BLUETOOTH_PROFILE_DESCRIPTOR_LIST); attribute = de_push_sequence(service); { uint8_t *a2dProfile = de_push_sequence(attribute); { de_add_number(a2dProfile, DE_UUID, DE_SIZE_16, BLUETOOTH_SERVICE_CLASS_ADVANCED_AUDIO_DISTRIBUTION); de_add_number(a2dProfile, DE_UINT, DE_SIZE_16, 0x0103); } de_pop_sequence(attribute, a2dProfile); } de_pop_sequence(service, attribute); // 0x0100 "Service Name" de_add_number(service, DE_UINT, DE_SIZE_16, 0x0100); if (service_name){ de_add_data(service, DE_STRING, strlen(service_name), (uint8_t *) service_name); } else { de_add_data(service, DE_STRING, strlen(default_a2dp_source_service_name), (uint8_t *) default_a2dp_source_service_name); } // 0x0100 "Provider Name" de_add_number(service, DE_UINT, DE_SIZE_16, 0x0102); if (service_provider_name){ de_add_data(service, DE_STRING, strlen(service_provider_name), (uint8_t *) service_provider_name); } else { de_add_data(service, DE_STRING, strlen(default_a2dp_source_service_provider_name), (uint8_t *) default_a2dp_source_service_provider_name); } // 0x0311 "Supported Features" de_add_number(service, DE_UINT, DE_SIZE_16, 0x0311); de_add_number(service, DE_UINT, DE_SIZE_16, supported_features); } static void a2dp_streaming_emit_connection_established(btstack_packet_handler_t callback, uint16_t cid, uint8_t local_seid, uint8_t remote_seid, uint8_t status){ if (!callback) return; uint8_t event[8]; int pos = 0; event[pos++] = HCI_EVENT_A2DP_META; event[pos++] = sizeof(event) - 2; event[pos++] = A2DP_SUBEVENT_STREAM_ESTABLISHED; little_endian_store_16(event, pos, cid); pos += 2; event[pos++] = local_seid; event[pos++] = remote_seid; event[pos++] = status; (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event)); } static void a2dp_streaming_emit_can_send_media_packet_now(btstack_packet_handler_t callback, uint16_t cid, uint8_t seid){ if (!callback) return; uint8_t event[8]; int pos = 0; event[pos++] = HCI_EVENT_A2DP_META; event[pos++] = sizeof(event) - 2; event[pos++] = A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW; little_endian_store_16(event, pos, cid); pos += 2; event[pos++] = seid; (*callback)(HCI_EVENT_PACKET, 0, event, sizeof(event)); } static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ UNUSED(channel); UNUSED(size); bd_addr_t event_addr; uint8_t signal_identifier; uint8_t status; avdtp_sep_t sep; uint8_t int_seid; uint8_t acp_seid; switch (packet_type) { case HCI_EVENT_PACKET: switch (hci_event_packet_get_type(packet)) { case HCI_EVENT_PIN_CODE_REQUEST: // inform about pin code request printf("Pin code request - using '0000'\n"); hci_event_pin_code_request_get_bd_addr(packet, event_addr); hci_send_cmd(&hci_pin_code_request_reply, &event_addr, 4, "0000"); break; case HCI_EVENT_DISCONNECTION_COMPLETE: // connection closed -> quit test app printf("\n --- a2dp source --- HCI_EVENT_DISCONNECTION_COMPLETE ---\n"); break; case HCI_EVENT_AVDTP_META: switch (packet[2]){ case AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED: avdtp_cid = avdtp_subevent_signaling_connection_established_get_avdtp_cid(packet); status = avdtp_subevent_signaling_connection_established_get_status(packet); if (status != 0){ printf(" --- a2dp source --- AVDTP_SUBEVENT_SIGNALING_CONNECTION could not be established, status %d ---\n", status); break; } sc.active_remote_sep = NULL; next_remote_sep_index_to_query = 0; app_state = A2DP_W2_DISCOVER_SEPS; printf(" --- a2dp source --- AVDTP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED, avdtp cid 0x%02x ---\n", avdtp_cid); avdtp_source_discover_stream_endpoints(avdtp_cid); break; case AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED: status = avdtp_subevent_streaming_connection_established_get_status(packet); avdtp_cid = avdtp_subevent_streaming_connection_established_get_avdtp_cid(packet); int_seid = avdtp_subevent_streaming_connection_established_get_int_seid(packet); acp_seid = avdtp_subevent_streaming_connection_established_get_acp_seid(packet); if (status != 0){ printf(" --- a2dp source --- AVDTP_SUBEVENT_STREAMING_CONNECTION could not be established, status %d ---\n", status); break; } app_state = A2DP_STREAMING_OPENED; a2dp_streaming_emit_connection_established(a2dp_source_context.a2dp_callback, avdtp_cid, int_seid, acp_seid, 0); printf(" --- a2dp source --- AVDTP_SUBEVENT_STREAMING_CONNECTION_ESTABLISHED --- avdtp_cid 0x%02x, local seid %d, remote seid %d\n", avdtp_cid, int_seid, acp_seid); break; case AVDTP_SUBEVENT_SIGNALING_SEP_FOUND: if (app_state != A2DP_W2_DISCOVER_SEPS) return; sep.seid = avdtp_subevent_signaling_sep_found_get_seid(packet); sep.in_use = avdtp_subevent_signaling_sep_found_get_in_use(packet); sep.media_type = avdtp_subevent_signaling_sep_found_get_media_type(packet); sep.type = avdtp_subevent_signaling_sep_found_get_sep_type(packet); printf(" --- a2dp source --- Found sep: seid %u, in_use %d, media type %d, sep type %d (1-SNK)\n", sep.seid, sep.in_use, sep.media_type, sep.type); break; case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY:{ printf(" AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY 0\n"); if (!sc.local_stream_endpoint) return; printf(" AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CAPABILITY 1\n"); uint8_t sampling_frequency = avdtp_choose_sbc_sampling_frequency(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_sampling_frequency_bitmap(packet)); uint8_t channel_mode = avdtp_choose_sbc_channel_mode(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_channel_mode_bitmap(packet)); uint8_t block_length = avdtp_choose_sbc_block_length(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_block_length_bitmap(packet)); uint8_t subbands = avdtp_choose_sbc_subbands(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_subbands_bitmap(packet)); uint8_t allocation_method = avdtp_choose_sbc_allocation_method(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_allocation_method_bitmap(packet)); uint8_t max_bitpool_value = avdtp_choose_sbc_max_bitpool_value(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_max_bitpool_value(packet)); uint8_t min_bitpool_value = avdtp_choose_sbc_min_bitpool_value(sc.local_stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_min_bitpool_value(packet)); sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[0] = (sampling_frequency << 4) | channel_mode; sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[1] = (block_length << 4) | (subbands << 2) | allocation_method; sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[2] = min_bitpool_value; sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_information[3] = max_bitpool_value; sc.local_stream_endpoint->remote_configuration_bitmap = store_bit16(sc.local_stream_endpoint->remote_configuration_bitmap, AVDTP_MEDIA_CODEC, 1); sc.local_stream_endpoint->remote_configuration.media_codec.media_type = AVDTP_AUDIO; sc.local_stream_endpoint->remote_configuration.media_codec.media_codec_type = AVDTP_CODEC_SBC; app_state = A2DP_W2_SET_CONFIGURATION; break; } case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CAPABILITY: printf(" --- a2dp source --- received non SBC codec. not implemented\n"); break; case AVDTP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{ sc.sampling_frequency = avdtp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet); sc.block_length = avdtp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet); sc.subbands = avdtp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet); switch (avdtp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet)){ case AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS: sc.allocation_method = SBC_LOUDNESS; break; case AVDTP_SBC_ALLOCATION_METHOD_SNR: sc.allocation_method = SBC_SNR; break; } sc.max_bitpool_value = avdtp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet); // TODO: deal with reconfigure: avdtp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet); break; } case AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW: a2dp_streaming_emit_can_send_media_packet_now(a2dp_source_context.a2dp_callback, avdtp_cid, 0); break; case AVDTP_SUBEVENT_SIGNALING_ACCEPT: signal_identifier = avdtp_subevent_signaling_accept_get_signal_identifier(packet); status = avdtp_subevent_signaling_accept_get_status(packet); printf(" --- a2dp source --- Accepted %d\n", signal_identifier); switch (app_state){ case A2DP_W2_DISCOVER_SEPS: app_state = A2DP_W2_GET_ALL_CAPABILITIES; sc.active_remote_sep = avdtp_source_remote_sep(avdtp_cid, next_remote_sep_index_to_query++); printf(" --- a2dp source --- Query get caps for seid %d\n", sc.active_remote_sep->seid); avdtp_source_get_capabilities(avdtp_cid, sc.active_remote_sep->seid); break; case A2DP_W2_GET_CAPABILITIES: case A2DP_W2_GET_ALL_CAPABILITIES: if (next_remote_sep_index_to_query < avdtp_source_remote_seps_num(avdtp_cid)){ sc.active_remote_sep = avdtp_source_remote_sep(avdtp_cid, next_remote_sep_index_to_query++); printf(" --- a2dp source --- Query get caps for seid %d\n", sc.active_remote_sep->seid); avdtp_source_get_capabilities(avdtp_cid, sc.active_remote_sep->seid); } else { printf(" --- a2dp source --- No more remote seps found\n"); app_state = A2DP_IDLE; } break; case A2DP_W2_SET_CONFIGURATION:{ if (!sc.local_stream_endpoint) return; app_state = A2DP_W2_GET_CONFIGURATION; avdtp_source_set_configuration(avdtp_cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.active_remote_sep->seid, sc.local_stream_endpoint->remote_configuration_bitmap, sc.local_stream_endpoint->remote_configuration); break; } case A2DP_W2_GET_CONFIGURATION: app_state = A2DP_W2_OPEN_STREAM_WITH_SEID; avdtp_source_get_configuration(avdtp_cid, sc.active_remote_sep->seid); break; case A2DP_W2_OPEN_STREAM_WITH_SEID:{ app_state = A2DP_W4_OPEN_STREAM_WITH_SEID; btstack_sbc_encoder_init(&sc.sbc_encoder_state, SBC_MODE_STANDARD, sc.block_length, sc.subbands, sc.allocation_method, sc.sampling_frequency, sc.max_bitpool_value); avdtp_source_open_stream(avdtp_cid, avdtp_stream_endpoint_seid(sc.local_stream_endpoint), sc.active_remote_sep->seid); break; } case A2DP_STREAMING_OPENED: if (!a2dp_source_context.a2dp_callback) return; switch (signal_identifier){ case AVDTP_SI_START:{ uint8_t event[6]; int pos = 0; event[pos++] = HCI_EVENT_A2DP_META; event[pos++] = sizeof(event) - 2; event[pos++] = A2DP_SUBEVENT_STREAM_START_ACCEPTED; little_endian_store_16(event, pos, avdtp_cid); pos += 2; event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint); (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event)); break; } case AVDTP_SI_CLOSE:{ uint8_t event[6]; int pos = 0; event[pos++] = HCI_EVENT_A2DP_META; event[pos++] = sizeof(event) - 2; event[pos++] = A2DP_SUBEVENT_STREAM_RELEASED; little_endian_store_16(event, pos, avdtp_cid); pos += 2; printf("send A2DP_SUBEVENT_STREAM_RELEASED to app\n"); event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint); (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event)); break; } case AVDTP_SI_SUSPEND:{ uint8_t event[6]; int pos = 0; event[pos++] = HCI_EVENT_A2DP_META; event[pos++] = sizeof(event) - 2; event[pos++] = A2DP_SUBEVENT_STREAM_SUSPENDED; little_endian_store_16(event, pos, avdtp_cid); pos += 2; event[pos++] = avdtp_stream_endpoint_seid(sc.local_stream_endpoint); (*a2dp_source_context.a2dp_callback)(HCI_EVENT_PACKET, 0, event, sizeof(event)); break; } default: break; } break; default: app_state = A2DP_IDLE; break; } break; case AVDTP_SUBEVENT_SIGNALING_REJECT: app_state = A2DP_IDLE; signal_identifier = avdtp_subevent_signaling_reject_get_signal_identifier(packet); printf(" --- a2dp source --- Rejected %d\n", signal_identifier); break; case AVDTP_SUBEVENT_SIGNALING_GENERAL_REJECT: app_state = A2DP_IDLE; signal_identifier = avdtp_subevent_signaling_general_reject_get_signal_identifier(packet); printf(" --- a2dp source --- Rejected %d\n", signal_identifier); break; default: app_state = A2DP_IDLE; printf(" --- a2dp source --- not implemented\n"); break; } break; default: break; } break; default: // other packet type break; } } void a2dp_source_register_packet_handler(btstack_packet_handler_t callback){ if (callback == NULL){ log_error("a2dp_source_register_packet_handler called with NULL callback"); return; } avdtp_source_register_packet_handler(&packet_handler); a2dp_source_context.a2dp_callback = callback; } void a2dp_source_init(void){ avdtp_source_init(&a2dp_source_context); l2cap_register_service(&packet_handler, BLUETOOTH_PROTOCOL_AVDTP, 0xffff, LEVEL_0); } uint8_t a2dp_source_create_stream_endpoint(avdtp_media_type_t media_type, avdtp_media_codec_type_t media_codec_type, uint8_t * codec_capabilities, uint16_t codec_capabilities_len, uint8_t * media_codec_info, uint16_t media_codec_info_len){ avdtp_stream_endpoint_t * local_stream_endpoint = avdtp_source_create_stream_endpoint(AVDTP_SOURCE, media_type); avdtp_source_register_media_transport_category(avdtp_stream_endpoint_seid(local_stream_endpoint)); avdtp_source_register_media_codec_category(avdtp_stream_endpoint_seid(local_stream_endpoint), media_type, media_codec_type, codec_capabilities, codec_capabilities_len); local_stream_endpoint->remote_configuration.media_codec.media_codec_information = media_codec_info; local_stream_endpoint->remote_configuration.media_codec.media_codec_information_len = media_codec_info_len; return local_stream_endpoint->sep.seid; } void a2dp_source_establish_stream(bd_addr_t bd_addr, uint8_t local_seid){ sc.local_stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context); if (!sc.local_stream_endpoint){ printf(" no local_stream_endpoint for seid %d\n", local_seid); } avdtp_source_connect(bd_addr); } void a2dp_source_disconnect(uint16_t con_handle){ avdtp_disconnect(con_handle, &a2dp_source_context); } void a2dp_source_start_stream(uint8_t int_seid){ avdtp_start_stream(int_seid, &a2dp_source_context); } void a2dp_source_release_stream(uint8_t int_seid){ avdtp_stop_stream(int_seid, &a2dp_source_context); } void a2dp_source_pause_stream(uint8_t int_seid){ avdtp_suspend_stream(int_seid, &a2dp_source_context); } uint8_t a2dp_source_stream_endpoint_ready(uint8_t local_seid){ avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context); if (!stream_endpoint) { printf("no stream_endpoint"); return 0; } return (stream_endpoint->state == AVDTP_STREAM_ENDPOINT_STREAMING); } static void a2dp_source_setup_media_header(uint8_t * media_packet, int size, int *offset, uint8_t marker, uint16_t sequence_number){ if (size < 12){ printf("small outgoing buffer\n"); return; } uint8_t rtp_version = 2; uint8_t padding = 0; uint8_t extension = 0; uint8_t csrc_count = 0; uint8_t payload_type = 0x60; // uint16_t sequence_number = stream_endpoint->sequence_number; uint32_t timestamp = btstack_run_loop_get_time_ms(); uint32_t ssrc = 0x11223344; // rtp header (min size 12B) int pos = 0; // int mtu = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid); media_packet[pos++] = (rtp_version << 6) | (padding << 5) | (extension << 4) | csrc_count; media_packet[pos++] = (marker << 1) | payload_type; big_endian_store_16(media_packet, pos, sequence_number); pos += 2; big_endian_store_32(media_packet, pos, timestamp); pos += 4; big_endian_store_32(media_packet, pos, ssrc); // only used for multicast pos += 4; *offset = pos; } static void a2dp_source_copy_media_payload(uint8_t * media_packet, int size, int * offset, btstack_ring_buffer_t * sbc_ring_buffer){ if (size < 18){ printf("small outgoing buffer\n"); return; } int pos = *offset; // media payload // sbc_header (size 1B) uint8_t sbc_header_index = pos; pos++; uint8_t fragmentation = 0; uint8_t starting_packet = 0; // set to 1 for the first packet of a fragmented SBC frame uint8_t last_packet = 0; // set to 1 for the last packet of a fragmented SBC frame uint8_t num_frames = 0; uint32_t total_sbc_bytes_read = 0; uint8_t sbc_frame_size = 0; // payload uint16_t sbc_frame_bytes = btstack_sbc_encoder_sbc_buffer_length(); while (size - 13 - total_sbc_bytes_read >= sbc_frame_bytes && btstack_ring_buffer_bytes_available(sbc_ring_buffer)){ uint32_t number_of_bytes_read = 0; btstack_ring_buffer_read(sbc_ring_buffer, &sbc_frame_size, 1, &number_of_bytes_read); btstack_ring_buffer_read(sbc_ring_buffer, media_packet + pos, sbc_frame_size, &number_of_bytes_read); pos += sbc_frame_size; total_sbc_bytes_read += sbc_frame_size; num_frames++; // printf("send sbc frame: timestamp %d, seq. nr %d\n", timestamp, stream_endpoint->sequence_number); } media_packet[sbc_header_index] = (fragmentation << 7) | (starting_packet << 6) | (last_packet << 5) | num_frames; *offset = pos; } void a2dp_source_stream_endpoint_request_can_send_now(uint8_t local_seid){ avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, &a2dp_source_context); if (!stream_endpoint) { printf("no stream_endpoint"); return; } stream_endpoint->send_stream = 1; avdtp_request_can_send_now_initiator(stream_endpoint->connection, stream_endpoint->l2cap_media_cid); } int a2dp_max_media_payload_size(uint8_t int_seid){ avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(int_seid, &a2dp_source_context); if (!stream_endpoint) { printf("no stream_endpoint found for seid %d", int_seid); return 0; } if (stream_endpoint->l2cap_media_cid == 0){ printf("no media cid found for seid %d", int_seid); return 0; } int sbc_header_size = 12; return l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid) - sbc_header_size; } int a2dp_source_stream_send_media_payload(uint8_t int_seid, btstack_ring_buffer_t * sbc_ring_buffer, uint8_t marker){ avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(int_seid, &a2dp_source_context); if (!stream_endpoint) { printf("no stream_endpoint found for seid %d", int_seid); return 0; } if (stream_endpoint->l2cap_media_cid == 0){ printf("no media cid found for seid %d", int_seid); return 0; } int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid); int offset = 0; l2cap_reserve_packet_buffer(); uint8_t * media_packet = l2cap_get_outgoing_buffer(); //int size = l2cap_get_remote_mtu_for_local_cid(stream_endpoint->l2cap_media_cid); a2dp_source_setup_media_header(media_packet, size, &offset, marker, stream_endpoint->sequence_number); a2dp_source_copy_media_payload(media_packet, size, &offset, sbc_ring_buffer); stream_endpoint->sequence_number++; l2cap_send_prepared(stream_endpoint->l2cap_media_cid, offset); return size; }