xref: /btstack/src/classic/avdtp.c (revision d40c3de009bce6994e726da5a427e08951b353d9)
1 /*
2  * Copyright (C) 2016 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define __BTSTACK_FILE__ "avdtp.c"
39 
40 
41 #include <stdint.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #include "btstack.h"
47 #include "avdtp.h"
48 #include "avdtp_util.h"
49 #include "avdtp_acceptor.h"
50 #include "avdtp_initiator.h"
51 
52 static int record_id = -1;
53 static uint8_t   attribute_value[1000];
54 static const unsigned int attribute_value_buffer_size = sizeof(attribute_value);
55 
56 typedef struct {
57     avdtp_connection_t * connection;
58     btstack_packet_handler_t avdtp_callback;
59     avdtp_sep_type_t query_role;
60     btstack_packet_handler_t packet_handler;
61 } avdtp_sdp_query_context_t;
62 
63 static avdtp_sdp_query_context_t sdp_query_context;
64 static uint16_t avdtp_cid_counter = 0;
65 
66 static void (*handle_media_data)(avdtp_stream_endpoint_t * stream_endpoint, uint8_t *packet, uint16_t size);
67 static void avdtp_handle_sdp_client_query_result(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
68 
69 static uint16_t avdtp_get_next_initiator_transaction_label(avdtp_context_t * context){
70     context->initiator_transaction_id_counter++;
71     if (context->initiator_transaction_id_counter == 0){
72         context->initiator_transaction_id_counter = 1;
73     }
74     return context->initiator_transaction_id_counter;
75 }
76 
77 static uint16_t avdtp_get_next_avdtp_cid(void){
78     avdtp_cid_counter++;
79     if (avdtp_cid_counter == 0){
80         avdtp_cid_counter = 1;
81     }
82     return avdtp_cid_counter;
83 }
84 
85 static uint16_t avdtp_get_next_local_seid(avdtp_context_t * context){
86     context->stream_endpoints_id_counter++;
87     if (context->stream_endpoints_id_counter == 0){
88         context->stream_endpoints_id_counter = 1;
89     }
90     return context->stream_endpoints_id_counter;
91 }
92 
93 uint8_t avdtp_connect(bd_addr_t remote, avdtp_sep_type_t query_role, avdtp_context_t * avdtp_context, uint16_t * avdtp_cid){
94     sdp_query_context.connection = NULL;
95     avdtp_connection_t * connection = avdtp_connection_for_bd_addr(remote, avdtp_context);
96     if (!connection){
97         connection = avdtp_create_connection(remote, avdtp_context);
98     }
99     if (connection->state != AVDTP_SIGNALING_CONNECTION_IDLE){
100         log_error("avdtp_connect: sink in wrong state,");
101         return BTSTACK_MEMORY_ALLOC_FAILED;
102     }
103 
104     if (!avdtp_cid) return L2CAP_LOCAL_CID_DOES_NOT_EXIST;
105 
106     *avdtp_cid = connection->avdtp_cid;
107     connection->state = AVDTP_SIGNALING_W4_SDP_QUERY_COMPLETE;
108     sdp_query_context.connection = connection;
109     sdp_query_context.query_role = query_role;
110     sdp_query_context.avdtp_callback = avdtp_context->avdtp_callback;
111     sdp_query_context.packet_handler = avdtp_context->packet_handler;
112 
113     sdp_client_query_uuid16(&avdtp_handle_sdp_client_query_result, remote, BLUETOOTH_PROTOCOL_AVDTP);
114     return ERROR_CODE_SUCCESS;
115 }
116 
117 void avdtp_register_media_transport_category(avdtp_stream_endpoint_t * stream_endpoint){
118     if (!stream_endpoint){
119         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
120         return;
121     }
122     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_MEDIA_TRANSPORT, 1);
123     stream_endpoint->sep.registered_service_categories = bitmap;
124 }
125 
126 void avdtp_register_reporting_category(avdtp_stream_endpoint_t * stream_endpoint){
127     if (!stream_endpoint){
128         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
129         return;
130     }
131     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_REPORTING, 1);
132     stream_endpoint->sep.registered_service_categories = bitmap;
133 }
134 
135 void avdtp_register_delay_reporting_category(avdtp_stream_endpoint_t * stream_endpoint){
136     if (!stream_endpoint){
137         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
138         return;
139     }
140     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_DELAY_REPORTING, 1);
141     stream_endpoint->sep.registered_service_categories = bitmap;
142 }
143 
144 void avdtp_register_recovery_category(avdtp_stream_endpoint_t * stream_endpoint, uint8_t maximum_recovery_window_size, uint8_t maximum_number_media_packets){
145     if (!stream_endpoint){
146         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
147         return;
148     }
149     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_RECOVERY, 1);
150     stream_endpoint->sep.registered_service_categories = bitmap;
151     stream_endpoint->sep.capabilities.recovery.recovery_type = 0x01; // 0x01 = RFC2733
152     stream_endpoint->sep.capabilities.recovery.maximum_recovery_window_size = maximum_recovery_window_size;
153     stream_endpoint->sep.capabilities.recovery.maximum_number_media_packets = maximum_number_media_packets;
154 }
155 
156 void avdtp_register_content_protection_category(avdtp_stream_endpoint_t * stream_endpoint, uint16_t cp_type, const uint8_t * cp_type_value, uint8_t cp_type_value_len){
157     if (!stream_endpoint){
158         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
159         return;
160     }
161     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_CONTENT_PROTECTION, 1);
162     stream_endpoint->sep.registered_service_categories = bitmap;
163     stream_endpoint->sep.capabilities.content_protection.cp_type = cp_type;
164     stream_endpoint->sep.capabilities.content_protection.cp_type_value = cp_type_value;
165     stream_endpoint->sep.capabilities.content_protection.cp_type_value_len = cp_type_value_len;
166 }
167 
168 void avdtp_register_header_compression_category(avdtp_stream_endpoint_t * stream_endpoint, uint8_t back_ch, uint8_t media, uint8_t recovery){
169     if (!stream_endpoint){
170         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
171         return;
172     }
173     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_HEADER_COMPRESSION, 1);
174     stream_endpoint->sep.registered_service_categories = bitmap;
175     stream_endpoint->sep.capabilities.header_compression.back_ch = back_ch;
176     stream_endpoint->sep.capabilities.header_compression.media = media;
177     stream_endpoint->sep.capabilities.header_compression.recovery = recovery;
178 }
179 
180 void avdtp_register_media_codec_category(avdtp_stream_endpoint_t * stream_endpoint, avdtp_media_type_t media_type, avdtp_media_codec_type_t media_codec_type, uint8_t * media_codec_info, uint16_t media_codec_info_len){
181     if (!stream_endpoint){
182         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
183         return;
184     }
185     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_MEDIA_CODEC, 1);
186     stream_endpoint->sep.registered_service_categories = bitmap;
187     stream_endpoint->sep.capabilities.media_codec.media_type = media_type;
188     stream_endpoint->sep.capabilities.media_codec.media_codec_type = media_codec_type;
189     stream_endpoint->sep.capabilities.media_codec.media_codec_information = media_codec_info;
190     stream_endpoint->sep.capabilities.media_codec.media_codec_information_len = media_codec_info_len;
191 }
192 
193 void avdtp_register_multiplexing_category(avdtp_stream_endpoint_t * stream_endpoint, uint8_t fragmentation){
194     if (!stream_endpoint){
195         log_error("avdtp_register_media_transport_category: stream endpoint with given seid is not registered");
196         return;
197     }
198     uint16_t bitmap = store_bit16(stream_endpoint->sep.registered_service_categories, AVDTP_MULTIPLEXING, 1);
199     stream_endpoint->sep.registered_service_categories = bitmap;
200     stream_endpoint->sep.capabilities.multiplexing_mode.fragmentation = fragmentation;
201 }
202 
203 
204 /* START: tracking can send now requests pro l2cap cid */
205 void avdtp_handle_can_send_now(avdtp_connection_t * connection, uint16_t l2cap_cid, avdtp_context_t * context){
206     if (connection->wait_to_send_acceptor){
207         connection->wait_to_send_acceptor = 0;
208         avdtp_acceptor_stream_config_subsm_run(connection, context);
209     } else if (connection->wait_to_send_initiator){
210         connection->wait_to_send_initiator = 0;
211         avdtp_initiator_stream_config_subsm_run(connection, context);
212     } else if (connection->wait_to_send_self){
213         connection->wait_to_send_self = 0;
214         if (connection->disconnect){
215             btstack_linked_list_iterator_t it;
216             btstack_linked_list_iterator_init(&it, &context->stream_endpoints);
217             while (btstack_linked_list_iterator_has_next(&it)){
218                 avdtp_stream_endpoint_t * stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
219                 if (stream_endpoint->connection == connection){
220                     if (stream_endpoint->state >= AVDTP_STREAM_ENDPOINT_OPENED && stream_endpoint->state != AVDTP_STREAM_ENDPOINT_W4_L2CAP_FOR_MEDIA_DISCONNECTED){
221                         stream_endpoint->state = AVDTP_STREAM_ENDPOINT_W4_L2CAP_FOR_MEDIA_DISCONNECTED;
222                         avdtp_request_can_send_now_self(connection, connection->l2cap_signaling_cid);
223                         l2cap_disconnect(stream_endpoint->l2cap_media_cid, 0);
224                         return;
225                     }
226                 }
227             }
228             connection->disconnect = 0;
229             connection->state = AVDTP_SIGNALING_CONNECTION_W4_L2CAP_DISCONNECTED;
230             l2cap_disconnect(connection->l2cap_signaling_cid, 0);
231             return;
232         }
233     }
234 
235     // re-register
236     int more_to_send = connection->wait_to_send_acceptor || connection->wait_to_send_initiator || connection->wait_to_send_self;
237     if (more_to_send){
238         l2cap_request_can_send_now_event(l2cap_cid);
239     }
240 }
241 /* END: tracking can send now requests pro l2cap cid */
242 
243 avdtp_connection_t * avdtp_create_connection(bd_addr_t remote_addr, avdtp_context_t * context){
244     avdtp_connection_t * connection = btstack_memory_avdtp_connection_get();
245     memset(connection, 0, sizeof(avdtp_connection_t));
246     connection->state = AVDTP_SIGNALING_CONNECTION_IDLE;
247     connection->initiator_transaction_label = avdtp_get_next_initiator_transaction_label(context);
248     connection->avdtp_cid = avdtp_get_next_avdtp_cid();
249     memcpy(connection->remote_addr, remote_addr, 6);
250     btstack_linked_list_add(&context->connections, (btstack_linked_item_t *) connection);
251     return connection;
252 }
253 
254 avdtp_stream_endpoint_t * avdtp_create_stream_endpoint(avdtp_sep_type_t sep_type, avdtp_media_type_t media_type, avdtp_context_t * context){
255     avdtp_stream_endpoint_t * stream_endpoint = btstack_memory_avdtp_stream_endpoint_get();
256     memset(stream_endpoint, 0, sizeof(avdtp_stream_endpoint_t));
257     stream_endpoint->sep.seid = avdtp_get_next_local_seid(context);
258     stream_endpoint->sep.media_type = media_type;
259     stream_endpoint->sep.type = sep_type;
260     btstack_linked_list_add(&context->stream_endpoints, (btstack_linked_item_t *) stream_endpoint);
261     return stream_endpoint;
262 }
263 
264 
265 static void handle_l2cap_data_packet_for_signaling_connection(avdtp_connection_t * connection, uint8_t *packet, uint16_t size, avdtp_context_t * context){
266     int offset = avdtp_read_signaling_header(&connection->signaling_packet, packet, size);
267     switch (connection->signaling_packet.message_type){
268         case AVDTP_CMD_MSG:
269             avdtp_acceptor_stream_config_subsm(connection, packet, size, offset, context);
270             break;
271         default:
272             avdtp_initiator_stream_config_subsm(connection, packet, size, offset, context);
273             break;
274     }
275 }
276 
277 static void stream_endpoint_state_machine(avdtp_connection_t * connection, avdtp_stream_endpoint_t * stream_endpoint, uint8_t packet_type, uint8_t event, uint8_t *packet, uint16_t size, avdtp_context_t * context){
278     uint16_t local_cid;
279     uint8_t  status;
280     switch (packet_type){
281         case L2CAP_DATA_PACKET:{
282             int offset = avdtp_read_signaling_header(&connection->signaling_packet, packet, size);
283             if (connection->signaling_packet.message_type == AVDTP_CMD_MSG){
284                 avdtp_acceptor_stream_config_subsm(connection, packet, size, offset, context);
285             } else {
286                 avdtp_initiator_stream_config_subsm(connection, packet, size, offset, context);
287             }
288             break;
289         }
290         case HCI_EVENT_PACKET:
291             switch (event){
292                 case L2CAP_EVENT_CHANNEL_OPENED:
293                     if (stream_endpoint->l2cap_media_cid == 0){
294                         if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_W4_L2CAP_FOR_MEDIA_CONNECTED){
295                             log_info(" -> AVDTP_STREAM_ENDPOINT_OPENED failed - stream endpoint in wrong state %d, avdtp cid 0x%02x, l2cap_media_cid 0x%02x, local seid %d, remote seid %d", stream_endpoint->state, connection->avdtp_cid, stream_endpoint->l2cap_media_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint));
296                             avdtp_streaming_emit_connection_established(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint), AVDTP_STREAM_ENDPOINT_IN_WRONG_STATE);
297                             break;
298                         }
299                         status = l2cap_event_channel_opened_get_status(packet);
300                         if (status){
301                             log_info(" -> AVDTP_STREAM_ENDPOINT_OPENED failed with status %d, avdtp cid 0x%02x, l2cap_media_cid 0x%02x, local seid %d, remote seid %d", status, connection->avdtp_cid, stream_endpoint->l2cap_media_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint));
302                             avdtp_streaming_emit_connection_established(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint), status);
303                             break;
304                         }
305                         stream_endpoint->state = AVDTP_STREAM_ENDPOINT_OPENED;
306                         stream_endpoint->connection = connection;
307                         stream_endpoint->l2cap_media_cid = l2cap_event_channel_opened_get_local_cid(packet);
308                         stream_endpoint->media_con_handle = l2cap_event_channel_opened_get_handle(packet);
309 
310                         // log_info(" -> AVDTP_STREAM_ENDPOINT_OPENED, avdtp cid 0x%02x, l2cap_media_cid 0x%02x, local seid %d, remote seid %d", connection->avdtp_cid, stream_endpoint->l2cap_media_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint));
311                         avdtp_streaming_emit_connection_established(context->avdtp_callback, connection->avdtp_cid, avdtp_local_seid(stream_endpoint), avdtp_remote_seid(stream_endpoint), 0);
312                         break;
313                     }
314                     break;
315                 case L2CAP_EVENT_CHANNEL_CLOSED:
316                     local_cid = l2cap_event_channel_closed_get_local_cid(packet);
317                     if (stream_endpoint->l2cap_media_cid == local_cid){
318                         avdtp_streaming_emit_connection_released(context->avdtp_callback, stream_endpoint->connection->avdtp_cid, avdtp_local_seid(stream_endpoint));
319                         stream_endpoint->l2cap_media_cid = 0;
320                         stream_endpoint->state = AVDTP_STREAM_ENDPOINT_IDLE;
321                         stream_endpoint->acceptor_config_state = AVDTP_ACCEPTOR_STREAM_CONFIG_IDLE;
322                         stream_endpoint->initiator_config_state = AVDTP_INITIATOR_STREAM_CONFIG_IDLE;
323                         stream_endpoint->remote_sep_index = 0;
324                         break;
325                     }
326                     if (stream_endpoint->l2cap_recovery_cid == local_cid){
327                         log_info(" -> L2CAP_EVENT_CHANNEL_CLOSED recovery cid 0x%0x", local_cid);
328                         stream_endpoint->l2cap_recovery_cid = 0;
329                         break;
330                     }
331 
332                     if (stream_endpoint->l2cap_reporting_cid == local_cid){
333                         log_info("L2CAP_EVENT_CHANNEL_CLOSED reporting cid 0x%0x", local_cid);
334                         stream_endpoint->l2cap_reporting_cid = 0;
335                         break;
336                     }
337                     break;
338                 default:
339                     break;
340             }
341             break;
342         default:
343             break;
344     }
345 }
346 
347 static void avdtp_handle_sdp_client_query_result(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
348     UNUSED(packet_type);
349     UNUSED(channel);
350     UNUSED(size);
351 
352     des_iterator_t des_list_it;
353     des_iterator_t prot_it;
354     uint16_t avdtp_l2cap_psm      = 0;
355     uint16_t avdtp_version        = 0;
356     // uint32_t avdtp_remote_uuid    = 0;
357 
358     if (!sdp_query_context.connection) return;
359 
360     switch (hci_event_packet_get_type(packet)){
361         case SDP_EVENT_QUERY_ATTRIBUTE_VALUE:
362             // Handle new SDP record
363             if (sdp_event_query_attribute_byte_get_record_id(packet) != record_id) {
364                 record_id = sdp_event_query_attribute_byte_get_record_id(packet);
365                 // log_info("SDP Record: Nr: %d", record_id);
366             }
367 
368             if (sdp_event_query_attribute_byte_get_attribute_length(packet) <= attribute_value_buffer_size) {
369                 attribute_value[sdp_event_query_attribute_byte_get_data_offset(packet)] = sdp_event_query_attribute_byte_get_data(packet);
370 
371                 if ((uint16_t)(sdp_event_query_attribute_byte_get_data_offset(packet)+1) == sdp_event_query_attribute_byte_get_attribute_length(packet)) {
372 
373                     switch(sdp_event_query_attribute_byte_get_attribute_id(packet)) {
374                         case BLUETOOTH_ATTRIBUTE_SERVICE_CLASS_ID_LIST:
375                             if (de_get_element_type(attribute_value) != DE_DES) break;
376                             for (des_iterator_init(&des_list_it, attribute_value); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
377                                 uint8_t * element = des_iterator_get_element(&des_list_it);
378                                 if (de_get_element_type(element) != DE_UUID) continue;
379                                 uint32_t uuid = de_get_uuid32(element);
380                                 switch (uuid){
381                                     case BLUETOOTH_SERVICE_CLASS_AUDIO_SOURCE:
382                                         if (sdp_query_context.query_role != AVDTP_SOURCE) {
383                                             sdp_query_context.connection->state = AVDTP_SIGNALING_CONNECTION_IDLE;
384                                             avdtp_signaling_emit_connection_established(sdp_query_context.avdtp_callback, sdp_query_context.connection->avdtp_cid, sdp_query_context.connection->remote_addr, SDP_SERVICE_NOT_FOUND);
385                                             break;
386                                         }
387                                         // log_info("SDP Attribute 0x%04x: AVDTP SOURCE protocol UUID: 0x%04x", sdp_event_query_attribute_byte_get_attribute_id(packet), uuid);
388                                         // avdtp_remote_uuid = uuid;
389                                         break;
390                                     case BLUETOOTH_SERVICE_CLASS_AUDIO_SINK:
391                                         if (sdp_query_context.query_role != AVDTP_SINK) {
392                                             sdp_query_context.connection->state = AVDTP_SIGNALING_CONNECTION_IDLE;
393                                             avdtp_signaling_emit_connection_established(sdp_query_context.avdtp_callback, sdp_query_context.connection->avdtp_cid, sdp_query_context.connection->remote_addr, SDP_SERVICE_NOT_FOUND);
394                                             break;
395                                         }
396                                         // log_info("SDP Attribute 0x%04x: AVDTP SINK protocol UUID: 0x%04x", sdp_event_query_attribute_byte_get_attribute_id(packet), uuid);
397                                         // avdtp_remote_uuid = uuid;
398                                         break;
399                                     default:
400                                         break;
401                                 }
402                             }
403                             break;
404 
405                         case BLUETOOTH_ATTRIBUTE_PROTOCOL_DESCRIPTOR_LIST: {
406                                 // log_info("SDP Attribute: 0x%04x", sdp_event_query_attribute_byte_get_attribute_id(packet));
407 
408                                 for (des_iterator_init(&des_list_it, attribute_value); des_iterator_has_more(&des_list_it); des_iterator_next(&des_list_it)) {
409                                     uint8_t       *des_element;
410                                     uint8_t       *element;
411                                     uint32_t       uuid;
412 
413                                     if (des_iterator_get_type(&des_list_it) != DE_DES) continue;
414 
415                                     des_element = des_iterator_get_element(&des_list_it);
416                                     des_iterator_init(&prot_it, des_element);
417                                     element = des_iterator_get_element(&prot_it);
418 
419                                     if (de_get_element_type(element) != DE_UUID) continue;
420 
421                                     uuid = de_get_uuid32(element);
422                                     switch (uuid){
423                                         case BLUETOOTH_PROTOCOL_L2CAP:
424                                             if (!des_iterator_has_more(&prot_it)) continue;
425                                             des_iterator_next(&prot_it);
426                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &avdtp_l2cap_psm);
427                                             break;
428                                         case BLUETOOTH_PROTOCOL_AVDTP:
429                                             if (!des_iterator_has_more(&prot_it)) continue;
430                                             des_iterator_next(&prot_it);
431                                             de_element_get_uint16(des_iterator_get_element(&prot_it), &avdtp_version);
432                                             break;
433                                         default:
434                                             break;
435                                     }
436                                 }
437                                 if (!avdtp_l2cap_psm) {
438                                     sdp_query_context.connection->state = AVDTP_SIGNALING_CONNECTION_IDLE;
439                                     avdtp_signaling_emit_connection_established(sdp_query_context.avdtp_callback, sdp_query_context.connection->avdtp_cid, sdp_query_context.connection->remote_addr, L2CAP_SERVICE_DOES_NOT_EXIST);
440                                     break;
441                                 }
442                                 sdp_query_context.connection->state = AVDTP_SIGNALING_CONNECTION_W4_L2CAP_CONNECTED;
443                                 l2cap_create_channel(sdp_query_context.packet_handler, sdp_query_context.connection->remote_addr, avdtp_l2cap_psm, l2cap_max_mtu(), NULL);
444                             }
445                             break;
446                         default:
447                             break;
448                     }
449                 }
450             } else {
451                 log_error("SDP attribute value buffer size exceeded: available %d, required %d", attribute_value_buffer_size, sdp_event_query_attribute_byte_get_attribute_length(packet));
452             }
453             break;
454 
455         case SDP_EVENT_QUERY_COMPLETE:
456             log_info("General query done with status %d.", sdp_event_query_complete_get_status(packet));
457             break;
458     }
459 }
460 
461 
462 void avdtp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size, avdtp_context_t * context){
463     bd_addr_t event_addr;
464     uint16_t psm;
465     uint16_t local_cid;
466     avdtp_stream_endpoint_t * stream_endpoint = NULL;
467     avdtp_connection_t * connection = NULL;
468     btstack_linked_list_t * avdtp_connections = &context->connections;
469     btstack_linked_list_t * stream_endpoints =  &context->stream_endpoints;
470     handle_media_data = context->handle_media_data;
471     // log_info("avdtp_packet_handler packet type %02x, event %02x ", packet_type, hci_event_packet_get_type(packet));
472     switch (packet_type) {
473         case L2CAP_DATA_PACKET:
474             connection = avdtp_connection_for_l2cap_signaling_cid(channel, context);
475             if (connection){
476                 handle_l2cap_data_packet_for_signaling_connection(connection, packet, size, context);
477                 break;
478             }
479 
480             stream_endpoint = avdtp_stream_endpoint_for_l2cap_cid(channel, context);
481             if (!stream_endpoint){
482                 if (!connection) break;
483                 handle_l2cap_data_packet_for_signaling_connection(connection, packet, size, context);
484                 break;
485             }
486 
487             if (channel == stream_endpoint->connection->l2cap_signaling_cid){
488                 stream_endpoint_state_machine(stream_endpoint->connection, stream_endpoint, L2CAP_DATA_PACKET, 0, packet, size, context);
489                 break;
490             }
491 
492             if (channel == stream_endpoint->l2cap_media_cid){
493                 if (handle_media_data){
494                     (*handle_media_data)(stream_endpoint, packet, size);
495                 }
496                 break;
497             }
498 
499             if (channel == stream_endpoint->l2cap_reporting_cid){
500                 // TODO
501                 log_info("L2CAP_DATA_PACKET for reporting: NOT IMPLEMENTED");
502             } else if (channel == stream_endpoint->l2cap_recovery_cid){
503                 // TODO
504                 log_info("L2CAP_DATA_PACKET for recovery: NOT IMPLEMENTED");
505             } else {
506                 log_error("avdtp packet handler L2CAP_DATA_PACKET: local cid 0x%02x not found", channel);
507             }
508             break;
509 
510         case HCI_EVENT_PACKET:
511             switch (hci_event_packet_get_type(packet)) {
512                 case L2CAP_EVENT_INCOMING_CONNECTION:
513                     l2cap_event_incoming_connection_get_address(packet, event_addr);
514                     local_cid = l2cap_event_incoming_connection_get_local_cid(packet);
515 
516                     connection = avdtp_connection_for_bd_addr(event_addr, context);
517 
518                     if (!connection || connection->state == AVDTP_SIGNALING_CONNECTION_W4_L2CAP_CONNECTED){
519                         connection = avdtp_create_connection(event_addr, context);
520                         connection->state = AVDTP_SIGNALING_CONNECTION_W4_L2CAP_CONNECTED;
521                         log_info("L2CAP_EVENT_INCOMING_CONNECTION, connection %p, state connection %d", connection, connection->state);
522                         l2cap_accept_connection(local_cid);
523                         break;
524                     }
525 
526                     stream_endpoint = avdtp_stream_endpoint_for_seid(connection->local_seid, context);
527                     if (!stream_endpoint) {
528                         log_info("L2CAP_EVENT_INCOMING_CONNECTION no streamendpoint found for seid %d", connection->local_seid);
529                         break;
530                     }
531 
532                     if (stream_endpoint->l2cap_media_cid == 0){
533                         if (stream_endpoint->state != AVDTP_STREAM_ENDPOINT_W4_L2CAP_FOR_MEDIA_CONNECTED) break;
534                         l2cap_accept_connection(local_cid);
535                         break;
536                     }
537                     break;
538 
539                 case L2CAP_EVENT_CHANNEL_OPENED:
540                     // inform about new l2cap connection
541                     l2cap_event_channel_opened_get_address(packet, event_addr);
542                     local_cid = l2cap_event_channel_opened_get_local_cid(packet);
543                     if (l2cap_event_channel_opened_get_status(packet)){
544                         avdtp_signaling_emit_connection_established(context->avdtp_callback, connection->avdtp_cid, event_addr, l2cap_event_channel_opened_get_status(packet));
545                         log_error("L2CAP connection to connection %s failed. status code 0x%02x",
546                             bd_addr_to_str(event_addr), l2cap_event_channel_opened_get_status(packet));
547                         break;
548                     }
549                     psm = l2cap_event_channel_opened_get_psm(packet);
550                     if (psm != BLUETOOTH_PROTOCOL_AVDTP){
551                         log_error("unexpected PSM - Not implemented yet, avdtp sink: L2CAP_EVENT_CHANNEL_OPENED");
552                         return;
553                     }
554 
555                     // log_info("L2CAP_EVENT_CHANNEL_OPENED: Channel successfully opened: %s, handle 0x%02x, psm 0x%02x, local cid 0x%02x, remote cid 0x%02x",
556                            // bd_addr_to_str(event_addr), l2cap_event_channel_opened_get_handle(packet), psm, local_cid, l2cap_event_channel_opened_get_remote_cid(packet));
557 
558                     if (psm != BLUETOOTH_PROTOCOL_AVDTP) break;
559 
560                     connection = avdtp_connection_for_bd_addr(event_addr, context);
561                     if (!connection) break;
562 
563                     if (connection->l2cap_signaling_cid == 0) {
564                         if (connection->state != AVDTP_SIGNALING_CONNECTION_W4_L2CAP_CONNECTED) break;
565                         connection->l2cap_signaling_cid = local_cid;
566                         connection->local_seid = 0;
567                         connection->state = AVDTP_SIGNALING_CONNECTION_OPENED;
568                         log_info(" -> AVDTP_SIGNALING_CONNECTION_OPENED, connection %p, avdtp_cid 0x%02x", connection, connection->avdtp_cid);
569                         avdtp_signaling_emit_connection_established(context->avdtp_callback, connection->avdtp_cid, event_addr, 0);
570                         break;
571                     }
572 
573                     stream_endpoint = avdtp_stream_endpoint_for_seid(connection->local_seid, context);
574                     if (!stream_endpoint){
575                         log_info("L2CAP_EVENT_CHANNEL_OPENED: stream_endpoint not found");
576                         return;
577                     }
578                     stream_endpoint_state_machine(connection, stream_endpoint, HCI_EVENT_PACKET, L2CAP_EVENT_CHANNEL_OPENED, packet, size, context);
579                     break;
580 
581                 case L2CAP_EVENT_CHANNEL_CLOSED:
582                     local_cid = l2cap_event_channel_closed_get_local_cid(packet);
583                     connection = avdtp_connection_for_l2cap_signaling_cid(local_cid, context);
584                     stream_endpoint = avdtp_stream_endpoint_for_l2cap_cid(local_cid, context);
585 
586                     if (stream_endpoint){
587                         stream_endpoint_state_machine(connection, stream_endpoint, HCI_EVENT_PACKET, L2CAP_EVENT_CHANNEL_CLOSED, packet, size, context);
588                         break;
589                     }
590 
591                     if (connection){
592                         avdtp_signaling_emit_connection_released(context->avdtp_callback, connection->avdtp_cid);
593                         btstack_linked_list_remove(avdtp_connections, (btstack_linked_item_t*) connection);
594                         btstack_linked_list_iterator_t it;
595                         btstack_linked_list_iterator_init(&it, stream_endpoints);
596                         while (btstack_linked_list_iterator_has_next(&it)){
597                             avdtp_stream_endpoint_t * _stream_endpoint = (avdtp_stream_endpoint_t *)btstack_linked_list_iterator_next(&it);
598 
599                             if (_stream_endpoint->connection == connection){
600                                 avdtp_initialize_stream_endpoint(_stream_endpoint);
601                             }
602                         }
603                         btstack_memory_avdtp_connection_free(connection);
604                         break;
605                     }
606                     break;
607 
608                 case HCI_EVENT_DISCONNECTION_COMPLETE:
609                     break;
610 
611                 case L2CAP_EVENT_CAN_SEND_NOW:
612                     connection = avdtp_connection_for_l2cap_signaling_cid(channel, context);
613                     if (!connection) {
614                         stream_endpoint = avdtp_stream_endpoint_for_l2cap_cid(channel, context);
615                         if (!stream_endpoint->connection) break;
616                         connection = stream_endpoint->connection;
617                     }
618                     avdtp_handle_can_send_now(connection, channel, context);
619                     break;
620                 default:
621                     log_info("unknown HCI event type %02x", hci_event_packet_get_type(packet));
622                     break;
623             }
624             break;
625 
626         default:
627             // other packet type
628             break;
629     }
630 }
631 
632 uint8_t avdtp_disconnect(uint16_t avdtp_cid, avdtp_context_t * context){
633     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
634     if (!connection) return BTSTACK_MEMORY_ALLOC_FAILED;
635     if (connection->state == AVDTP_SIGNALING_CONNECTION_IDLE) return AVDTP_CONNECTION_IN_WRONG_STATE;
636     if (connection->state == AVDTP_SIGNALING_CONNECTION_W4_L2CAP_DISCONNECTED) return AVDTP_CONNECTION_IN_WRONG_STATE;
637 
638     connection->disconnect = 1;
639     avdtp_request_can_send_now_self(connection, connection->l2cap_signaling_cid);
640     return ERROR_CODE_SUCCESS;
641 }
642 
643 uint8_t avdtp_open_stream(uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, avdtp_context_t * context){
644     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
645     if (!connection){
646         log_error("avdtp_media_connect: no connection for signaling cid 0x%02x found", avdtp_cid);
647         return AVDTP_CONNECTION_DOES_NOT_EXIST;
648     }
649     if (avdtp_find_remote_sep(connection, remote_seid) == 0xFF){
650         log_error("avdtp_media_connect: no remote sep for seid %d found", remote_seid);
651         return AVDTP_SEID_DOES_NOT_EXIST;
652     }
653 
654     if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) {
655         log_error("avdtp_media_connect: wrong connection state %d", connection->state);
656         return AVDTP_CONNECTION_IN_WRONG_STATE;
657     }
658 
659     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_with_seid(local_seid, context);
660     if (!stream_endpoint) {
661         log_error("avdtp_media_connect: no stream_endpoint with seid %d found", local_seid);
662         return AVDTP_SEID_DOES_NOT_EXIST;
663     }
664 
665     if (stream_endpoint->state < AVDTP_STREAM_ENDPOINT_CONFIGURED) return AVDTP_STREAM_ENDPOINT_IN_WRONG_STATE;
666     if (stream_endpoint->remote_sep_index == AVDTP_INVALID_SEP_INDEX) return AVDTP_SEID_DOES_NOT_EXIST;
667 
668     connection->initiator_transaction_label++;
669     connection->remote_seid = remote_seid;
670     connection->local_seid = local_seid;
671     stream_endpoint->initiator_config_state = AVDTP_INITIATOR_W2_OPEN_STREAM;
672     stream_endpoint->state = AVDTP_STREAM_ENDPOINT_W2_REQUEST_OPEN_STREAM;
673     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
674     return ERROR_CODE_SUCCESS;
675 }
676 
677 uint8_t avdtp_start_stream(uint16_t avdtp_cid, uint8_t local_seid, avdtp_context_t * context){
678     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
679     if (!connection){
680         log_error("avdtp_start_stream: no connection for signaling cid 0x%02x found", avdtp_cid);
681         return AVDTP_CONNECTION_DOES_NOT_EXIST;
682     }
683 
684     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_with_seid(local_seid, context);
685     if (!stream_endpoint) {
686         log_error("avdtp_start_stream: no stream_endpoint with seid %d found", local_seid);
687         return AVDTP_SEID_DOES_NOT_EXIST;
688     }
689 
690     if (stream_endpoint->l2cap_media_cid == 0){
691         log_error("avdtp_start_stream: no media connection for stream_endpoint with seid %d found", local_seid);
692         return AVDTP_MEDIA_CONNECTION_DOES_NOT_EXIST;
693     }
694 
695     if (stream_endpoint->remote_sep_index == AVDTP_INVALID_SEP_INDEX || stream_endpoint->start_stream){
696         return AVDTP_STREAM_ENDPOINT_IN_WRONG_STATE;
697     }
698 
699     stream_endpoint->start_stream = 1;
700     connection->local_seid = local_seid;
701     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
702     return ERROR_CODE_SUCCESS;
703 }
704 
705 uint8_t avdtp_stop_stream(uint16_t avdtp_cid, uint8_t local_seid, avdtp_context_t * context){
706     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
707     if (!connection){
708         log_error("avdtp_stop_stream: no connection for signaling cid 0x%02x found", avdtp_cid);
709         return AVDTP_CONNECTION_DOES_NOT_EXIST;
710     }
711 
712     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_with_seid(local_seid, context);
713     if (!stream_endpoint) {
714         log_error("avdtp_stop_stream: no stream_endpoint with seid %d found", local_seid);
715         return AVDTP_SEID_DOES_NOT_EXIST;
716     }
717 
718     if (stream_endpoint->l2cap_media_cid == 0){
719         log_error("avdtp_stop_stream: no media connection for stream_endpoint with seid %d found", local_seid);
720         return AVDTP_MEDIA_CONNECTION_DOES_NOT_EXIST;
721     }
722     if (stream_endpoint->remote_sep_index == 0xFF || stream_endpoint->stop_stream) return ERROR_CODE_SUCCESS;
723 
724     stream_endpoint->stop_stream = 1;
725     connection->local_seid = local_seid;
726     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
727     return ERROR_CODE_SUCCESS;
728 }
729 
730 uint8_t avdtp_abort_stream(uint16_t avdtp_cid, uint8_t local_seid, avdtp_context_t * context){
731     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
732     if (!connection){
733         log_error("avdtp_abort_stream: no connection for signaling cid 0x%02x found", avdtp_cid);
734         return AVDTP_CONNECTION_DOES_NOT_EXIST;
735     }
736 
737     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_with_seid(local_seid, context);
738     if (!stream_endpoint) {
739         log_error("avdtp_abort_stream: no stream_endpoint with seid %d found", local_seid);
740         return AVDTP_SEID_DOES_NOT_EXIST;
741     }
742 
743     if (stream_endpoint->l2cap_media_cid == 0){
744         log_error("avdtp_abort_stream: no media connection for stream_endpoint with seid %d found", local_seid);
745         return AVDTP_MEDIA_CONNECTION_DOES_NOT_EXIST;
746     }
747     if (stream_endpoint->remote_sep_index == 0xFF || stream_endpoint->abort_stream) return ERROR_CODE_SUCCESS;
748 
749     stream_endpoint->abort_stream = 1;
750     connection->local_seid = local_seid;
751     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
752     return ERROR_CODE_SUCCESS;
753 }
754 
755 uint8_t avdtp_suspend_stream(uint16_t avdtp_cid, uint8_t local_seid, avdtp_context_t * context){
756     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
757     if (!connection){
758         log_error("avdtp_suspend_stream: no connection for signaling cid 0x%02x found", avdtp_cid);
759         return AVDTP_CONNECTION_DOES_NOT_EXIST;
760     }
761 
762     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_with_seid(local_seid, context);
763     if (!stream_endpoint) {
764         log_error("avdtp_suspend_stream: no stream_endpoint with seid %d found", local_seid);
765         return AVDTP_SEID_DOES_NOT_EXIST;
766     }
767 
768     if (stream_endpoint->l2cap_media_cid == 0){
769         log_error("avdtp_suspend_stream: no media connection for stream_endpoint with seid %d found", local_seid);
770         return AVDTP_MEDIA_CONNECTION_DOES_NOT_EXIST;
771     }
772     if (stream_endpoint->remote_sep_index == 0xFF || stream_endpoint->suspend_stream) return ERROR_CODE_SUCCESS;
773 
774     stream_endpoint->suspend_stream = 1;
775     connection->local_seid = local_seid;
776     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
777     return ERROR_CODE_SUCCESS;
778 }
779 
780 void avdtp_discover_stream_endpoints(uint16_t avdtp_cid, avdtp_context_t * context){
781     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
782     if (!connection){
783         log_error("avdtp_discover_stream_endpoints: no connection for signaling cid 0x%02x found", avdtp_cid);
784         return;
785     }
786     if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) return;
787 
788     switch (connection->initiator_connection_state){
789         case AVDTP_SIGNALING_CONNECTION_INITIATOR_IDLE:
790             connection->initiator_transaction_label++;
791             connection->initiator_connection_state = AVDTP_SIGNALING_CONNECTION_INITIATOR_W2_DISCOVER_SEPS;
792             avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
793             break;
794         default:
795             log_error("avdtp_discover_stream_endpoints: wrong state");
796             break;
797     }
798 }
799 
800 
801 void avdtp_get_capabilities(uint16_t avdtp_cid, uint8_t remote_seid, avdtp_context_t * context){
802     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
803     if (!connection){
804         log_error("avdtp_get_capabilities: no connection for AVDTP cid 0x%02x found", avdtp_cid);
805         return;
806     }
807     if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) return;
808     if (connection->initiator_connection_state != AVDTP_SIGNALING_CONNECTION_INITIATOR_IDLE) return;
809     connection->initiator_transaction_label++;
810     connection->initiator_connection_state = AVDTP_SIGNALING_CONNECTION_INITIATOR_W2_GET_CAPABILITIES;
811     connection->remote_seid = remote_seid;
812     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
813 }
814 
815 
816 void avdtp_get_all_capabilities(uint16_t avdtp_cid, uint8_t remote_seid, avdtp_context_t * context){
817     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
818     if (!connection){
819         log_error("avdtp_get_all_capabilities: no connection for AVDTP cid 0x%02x found", avdtp_cid);
820         return;
821     }
822     if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) return;
823     if (connection->initiator_connection_state != AVDTP_SIGNALING_CONNECTION_INITIATOR_IDLE) return;
824     connection->initiator_transaction_label++;
825     connection->initiator_connection_state = AVDTP_SIGNALING_CONNECTION_INITIATOR_W2_GET_ALL_CAPABILITIES;
826     connection->remote_seid = remote_seid;
827     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
828 }
829 
830 void avdtp_get_configuration(uint16_t avdtp_cid, uint8_t remote_seid, avdtp_context_t * context){
831     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
832     if (!connection){
833         log_error("avdtp_get_configuration: no connection for AVDTP cid 0x%02x found", avdtp_cid);
834         return;
835     }
836     if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) return;
837     if (connection->initiator_connection_state != AVDTP_SIGNALING_CONNECTION_INITIATOR_IDLE) return;
838     connection->initiator_transaction_label++;
839     connection->initiator_connection_state = AVDTP_SIGNALING_CONNECTION_INITIATOR_W2_GET_CONFIGURATION;
840     connection->remote_seid = remote_seid;
841     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
842 }
843 
844 void avdtp_set_configuration(uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, uint16_t configured_services_bitmap, avdtp_capabilities_t configuration, avdtp_context_t * context){
845     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
846     if (!connection){
847         log_error("avdtp_set_configuration: no connection for AVDTP cid 0x%02x found", avdtp_cid);
848         return;
849     }
850     if (connection->state != AVDTP_SIGNALING_CONNECTION_OPENED) return;
851     if (connection->initiator_connection_state != AVDTP_SIGNALING_CONNECTION_INITIATOR_IDLE) return;
852 
853     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, context);
854     if (!stream_endpoint) {
855         log_error("avdtp_set_configuration: no initiator stream endpoint for seid %d", local_seid);
856         return;
857     }
858 
859     connection->initiator_transaction_label++;
860     connection->remote_seid = remote_seid;
861     connection->local_seid = local_seid;
862     stream_endpoint->remote_configuration_bitmap = configured_services_bitmap;
863     stream_endpoint->remote_configuration = configuration;
864     stream_endpoint->initiator_config_state = AVDTP_INITIATOR_W2_SET_CONFIGURATION;
865     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
866 }
867 
868 void avdtp_reconfigure(uint16_t avdtp_cid, uint8_t local_seid, uint8_t remote_seid, uint16_t configured_services_bitmap, avdtp_capabilities_t configuration, avdtp_context_t * context){
869     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
870     if (!connection){
871         log_error("avdtp_reconfigure: no connection for AVDTP cid 0x%02x found", avdtp_cid);
872         return;
873     }
874     //TODO: if opened only app capabilities, enable reconfigure for not opened
875     if (connection->state < AVDTP_SIGNALING_CONNECTION_OPENED) return;
876     if (connection->initiator_connection_state != AVDTP_SIGNALING_CONNECTION_INITIATOR_IDLE) return;
877 
878     avdtp_stream_endpoint_t * stream_endpoint = avdtp_stream_endpoint_for_seid(local_seid, context);
879     if (!stream_endpoint) {
880         log_error("avdtp_reconfigure: no initiator stream endpoint for seid %d", local_seid);
881         return;
882     }
883 
884     if (stream_endpoint->remote_sep_index == 0xFF){
885         log_error("avdtp_reconfigure: no associated remote sep");
886         return;
887     }
888 
889     connection->initiator_transaction_label++;
890     connection->remote_seid = remote_seid;
891     connection->local_seid = local_seid;
892     stream_endpoint->remote_configuration_bitmap = configured_services_bitmap;
893     stream_endpoint->remote_configuration = configuration;
894     stream_endpoint->initiator_config_state = AVDTP_INITIATOR_W2_RECONFIGURE_STREAM_WITH_SEID;
895     printf("AVDTP_INITIATOR_W2_RECONFIGURE_STREAM_WITH_SEID \n");
896     avdtp_request_can_send_now_initiator(connection, connection->l2cap_signaling_cid);
897 }
898 
899 uint8_t avdtp_remote_seps_num(uint16_t avdtp_cid, avdtp_context_t * context){
900     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
901     if (!connection){
902         log_error("avdtp_suspend: no connection for AVDTP cid 0x%02x found", avdtp_cid);
903         return 0;
904     }
905     return connection->remote_seps_num;
906 }
907 
908 avdtp_sep_t * avdtp_remote_sep(uint16_t avdtp_cid, uint8_t index, avdtp_context_t * context){
909     avdtp_connection_t * connection = avdtp_connection_for_avdtp_cid(avdtp_cid, context);
910     if (!connection){
911         log_error("avdtp_suspend: no connection for AVDTP cid 0x%02x found", avdtp_cid);
912         return NULL;
913     }
914     return &connection->remote_seps[index];
915 }
916 
917 void avdtp_initialize_sbc_configuration_storage(avdtp_stream_endpoint_t * stream_endpoint, uint8_t * config_storage, uint16_t storage_size, uint8_t * packet, uint16_t packet_size){
918     UNUSED(packet_size);
919     if (storage_size < 4) {
920         log_error("storage must have 4 bytes");
921         return;
922     }
923     uint8_t sampling_frequency = avdtp_choose_sbc_sampling_frequency(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_sampling_frequency_bitmap(packet));
924     uint8_t channel_mode = avdtp_choose_sbc_channel_mode(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_channel_mode_bitmap(packet));
925     uint8_t block_length = avdtp_choose_sbc_block_length(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_block_length_bitmap(packet));
926     uint8_t subbands = avdtp_choose_sbc_subbands(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_subbands_bitmap(packet));
927 
928     uint8_t allocation_method = avdtp_choose_sbc_allocation_method(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_allocation_method_bitmap(packet));
929     uint8_t max_bitpool_value = avdtp_choose_sbc_max_bitpool_value(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_max_bitpool_value(packet));
930     uint8_t min_bitpool_value = avdtp_choose_sbc_min_bitpool_value(stream_endpoint, avdtp_subevent_signaling_media_codec_sbc_capability_get_min_bitpool_value(packet));
931 
932     config_storage[0] = (sampling_frequency << 4) | channel_mode;
933     config_storage[1] = (block_length << 4) | (subbands << 2) | allocation_method;
934     config_storage[2] = min_bitpool_value;
935     config_storage[3] = max_bitpool_value;
936 
937     stream_endpoint->remote_configuration_bitmap = store_bit16(stream_endpoint->remote_configuration_bitmap, AVDTP_MEDIA_CODEC, 1);
938     stream_endpoint->remote_configuration.media_codec.media_type = AVDTP_AUDIO;
939     stream_endpoint->remote_configuration.media_codec.media_codec_type = AVDTP_CODEC_SBC;
940     stream_endpoint->remote_configuration.media_codec.media_codec_information_len = storage_size;
941     stream_endpoint->remote_configuration.media_codec.media_codec_information = config_storage;
942 }
943 
944 uint8_t avdtp_choose_sbc_channel_mode(avdtp_stream_endpoint_t * stream_endpoint, uint8_t remote_channel_mode_bitmap){
945     uint8_t * media_codec = stream_endpoint->sep.capabilities.media_codec.media_codec_information;
946     uint8_t channel_mode_bitmap = (media_codec[0] & 0x0F) & remote_channel_mode_bitmap;
947 
948     uint8_t channel_mode = AVDTP_SBC_STEREO;
949     if (channel_mode_bitmap & AVDTP_SBC_JOINT_STEREO){
950         channel_mode = AVDTP_SBC_JOINT_STEREO;
951     } else if (channel_mode_bitmap & AVDTP_SBC_STEREO){
952         channel_mode = AVDTP_SBC_STEREO;
953     } else if (channel_mode_bitmap & AVDTP_SBC_DUAL_CHANNEL){
954         channel_mode = AVDTP_SBC_DUAL_CHANNEL;
955     } else if (channel_mode_bitmap & AVDTP_SBC_MONO){
956         channel_mode = AVDTP_SBC_MONO;
957     }
958     return channel_mode;
959 }
960 
961 uint8_t avdtp_choose_sbc_allocation_method(avdtp_stream_endpoint_t * stream_endpoint, uint8_t remote_allocation_method_bitmap){
962     uint8_t * media_codec = stream_endpoint->sep.capabilities.media_codec.media_codec_information;
963     uint8_t allocation_method_bitmap = (media_codec[1] & 0x03) & remote_allocation_method_bitmap;
964 
965     uint8_t allocation_method = AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS;
966     if (allocation_method_bitmap & AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS){
967         allocation_method = AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS;
968     } else if (allocation_method_bitmap & AVDTP_SBC_ALLOCATION_METHOD_SNR){
969         allocation_method = AVDTP_SBC_ALLOCATION_METHOD_SNR;
970     }
971     return allocation_method;
972 }
973 
974 uint8_t avdtp_stream_endpoint_seid(avdtp_stream_endpoint_t * stream_endpoint){
975     if (!stream_endpoint) return 0;
976     return stream_endpoint->sep.seid;
977 }
978 uint8_t avdtp_choose_sbc_subbands(avdtp_stream_endpoint_t * stream_endpoint, uint8_t remote_subbands_bitmap){
979     uint8_t * media_codec = stream_endpoint->sep.capabilities.media_codec.media_codec_information;
980     uint8_t subbands_bitmap = ((media_codec[1] >> 2) & 0x03) & remote_subbands_bitmap;
981 
982     uint8_t subbands = AVDTP_SBC_SUBBANDS_8;
983     if (subbands_bitmap & AVDTP_SBC_SUBBANDS_8){
984         subbands = AVDTP_SBC_SUBBANDS_8;
985     } else if (subbands_bitmap & AVDTP_SBC_SUBBANDS_4){
986         subbands = AVDTP_SBC_SUBBANDS_4;
987     }
988     return subbands;
989 }
990 
991 uint8_t avdtp_choose_sbc_block_length(avdtp_stream_endpoint_t * stream_endpoint, uint8_t remote_block_length_bitmap){
992     uint8_t * media_codec = stream_endpoint->sep.capabilities.media_codec.media_codec_information;
993     uint8_t block_length_bitmap = (media_codec[1] >> 4) & remote_block_length_bitmap;
994 
995     uint8_t block_length = AVDTP_SBC_BLOCK_LENGTH_16;
996     if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_16){
997         block_length = AVDTP_SBC_BLOCK_LENGTH_16;
998     } else if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_12){
999         block_length = AVDTP_SBC_BLOCK_LENGTH_12;
1000     } else if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_8){
1001         block_length = AVDTP_SBC_BLOCK_LENGTH_8;
1002     } else if (block_length_bitmap & AVDTP_SBC_BLOCK_LENGTH_4){
1003         block_length = AVDTP_SBC_BLOCK_LENGTH_4;
1004     }
1005     return block_length;
1006 }
1007 
1008 uint8_t avdtp_choose_sbc_sampling_frequency(avdtp_stream_endpoint_t * stream_endpoint, uint8_t remote_sampling_frequency_bitmap){
1009     uint8_t * media_codec = stream_endpoint->sep.capabilities.media_codec.media_codec_information;
1010     uint8_t sampling_frequency_bitmap = (media_codec[0] >> 4) & remote_sampling_frequency_bitmap;
1011 
1012     uint8_t sampling_frequency = AVDTP_SBC_44100;
1013     if (sampling_frequency_bitmap & AVDTP_SBC_48000){
1014         sampling_frequency = AVDTP_SBC_48000;
1015     } else if (sampling_frequency_bitmap & AVDTP_SBC_44100){
1016         sampling_frequency = AVDTP_SBC_44100;
1017     } else if (sampling_frequency_bitmap & AVDTP_SBC_32000){
1018         sampling_frequency = AVDTP_SBC_32000;
1019     } else if (sampling_frequency_bitmap & AVDTP_SBC_16000){
1020         sampling_frequency = AVDTP_SBC_16000;
1021     }
1022     return sampling_frequency;
1023 }
1024 
1025 uint8_t avdtp_choose_sbc_max_bitpool_value(avdtp_stream_endpoint_t * stream_endpoint, uint8_t remote_max_bitpool_value){
1026     uint8_t * media_codec = stream_endpoint->sep.capabilities.media_codec.media_codec_information;
1027     return btstack_min(media_codec[3], remote_max_bitpool_value);
1028 }
1029 
1030 uint8_t avdtp_choose_sbc_min_bitpool_value(avdtp_stream_endpoint_t * stream_endpoint, uint8_t remote_min_bitpool_value){
1031     uint8_t * media_codec = stream_endpoint->sep.capabilities.media_codec.media_codec_information;
1032     return btstack_max(media_codec[2], remote_min_bitpool_value);
1033 }
1034