xref: /btstack/src/hci.c (revision ed35553486def2c96984eb02aa2be495d8fa962c)
1 /*
2  * Copyright (C) 2009 by Matthias Ringwald
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  *
17  * THIS SOFTWARE IS PROVIDED BY MATTHIAS RINGWALD AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
20  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
21  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
24  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
27  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 /*
33  *  hci.c
34  *
35  *  Created by Matthias Ringwald on 4/29/09.
36  *
37  */
38 
39 #include "hci.h"
40 
41 #include <stdarg.h>
42 #include <string.h>
43 #include <stdio.h>
44 
45 #ifndef EMBEDDED
46 #include <unistd.h> // gethostbyname
47 #endif
48 
49 #include "btstack_memory.h"
50 #include "debug.h"
51 #include "hci_dump.h"
52 
53 #include <btstack/hci_cmds.h>
54 #include <btstack/version.h>
55 
56 // tmpe
57 #include "l2cap.h"
58 
59 #define HCI_CONNECTION_TIMEOUT_MS 10000
60 
61 // the STACK is here
62 static hci_stack_t       hci_stack;
63 
64 /**
65  * get connection for a given handle
66  *
67  * @return connection OR NULL, if not found
68  */
69 hci_connection_t * connection_for_handle(hci_con_handle_t con_handle){
70     linked_item_t *it;
71     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
72         if ( ((hci_connection_t *) it)->con_handle == con_handle){
73             return (hci_connection_t *) it;
74         }
75     }
76     return NULL;
77 }
78 
79 static void hci_connection_timeout_handler(timer_source_t *timer){
80     hci_connection_t * connection = linked_item_get_user(&timer->item);
81 #ifdef HAVE_TIME
82     struct timeval tv;
83     gettimeofday(&tv, NULL);
84     if (tv.tv_sec >= connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000) {
85         // connections might be timed out
86         hci_emit_l2cap_check_timeout(connection);
87     }
88 #endif
89 #ifdef HAVE_TICK
90     if (embedded_get_ticks() > connection->timestamp + embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
91         // connections might be timed out
92         hci_emit_l2cap_check_timeout(connection);
93     }
94 #endif
95     run_loop_set_timer(timer, HCI_CONNECTION_TIMEOUT_MS);
96     run_loop_add_timer(timer);
97 }
98 
99 static void hci_connection_timestamp(hci_connection_t *connection){
100 #ifdef HAVE_TIME
101     gettimeofday(&connection->timestamp, NULL);
102 #endif
103 #ifdef HAVE_TICK
104     connection->timestamp = embedded_get_ticks();
105 #endif
106 }
107 
108 /**
109  * create connection for given address
110  *
111  * @return connection OR NULL, if no memory left
112  */
113 static hci_connection_t * create_connection_for_addr(bd_addr_t addr){
114     hci_connection_t * conn = btstack_memory_hci_connection_get();
115     if (!conn) return NULL;
116     BD_ADDR_COPY(conn->address, addr);
117     conn->con_handle = 0xffff;
118     conn->authentication_flags = AUTH_FLAGS_NONE;
119     linked_item_set_user(&conn->timeout.item, conn);
120     conn->timeout.process = hci_connection_timeout_handler;
121     hci_connection_timestamp(conn);
122     conn->acl_recombination_length = 0;
123     conn->acl_recombination_pos = 0;
124     conn->num_acl_packets_sent = 0;
125     linked_list_add(&hci_stack.connections, (linked_item_t *) conn);
126     return conn;
127 }
128 
129 /**
130  * get connection for given address
131  *
132  * @return connection OR NULL, if not found
133  */
134 static hci_connection_t * connection_for_address(bd_addr_t address){
135     linked_item_t *it;
136     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
137         if ( ! BD_ADDR_CMP( ((hci_connection_t *) it)->address, address) ){
138             return (hci_connection_t *) it;
139         }
140     }
141     return NULL;
142 }
143 
144 /**
145  * add authentication flags and reset timer
146  */
147 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
148     bd_addr_t addr;
149     bt_flip_addr(addr, *(bd_addr_t *) bd_addr);
150     hci_connection_t * conn = connection_for_address(addr);
151     if (conn) {
152         conn->authentication_flags |= flags;
153         hci_connection_timestamp(conn);
154     }
155 }
156 
157 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
158     hci_connection_t * conn = connection_for_handle(handle);
159     if (!conn) return 0;
160     if (!conn->authentication_flags) return 0;
161     if (conn->authentication_flags & SENT_LINK_KEY_REPLY) return 0;
162     if (conn->authentication_flags & RECV_LINK_KEY_NOTIFICATION) return 0;
163     return 1;
164 }
165 
166 void hci_drop_link_key_for_bd_addr(bd_addr_t *addr){
167     if (hci_stack.remote_device_db) {
168         hci_stack.remote_device_db->delete_link_key(addr);
169     }
170 }
171 
172 
173 /**
174  * count connections
175  */
176 static int nr_hci_connections(void){
177     int count = 0;
178     linked_item_t *it;
179     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next, count++);
180     return count;
181 }
182 
183 /**
184  * Dummy handler called by HCI
185  */
186 static void dummy_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
187 }
188 
189 uint8_t hci_number_outgoing_packets(hci_con_handle_t handle){
190     hci_connection_t * connection = connection_for_handle(handle);
191     if (!connection) {
192         log_error("hci_number_outgoing_packets connectino for handle %u does not exist!\n", handle);
193         return 0;
194     }
195     return connection->num_acl_packets_sent;
196 }
197 
198 uint8_t hci_number_free_acl_slots(){
199     uint8_t free_slots = hci_stack.total_num_acl_packets;
200     linked_item_t *it;
201     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
202         hci_connection_t * connection = (hci_connection_t *) it;
203         if (free_slots < connection->num_acl_packets_sent) {
204             log_error("hci_number_free_acl_slots: sum of outgoing packets > total acl packets!\n");
205             return 0;
206         }
207         free_slots -= connection->num_acl_packets_sent;
208     }
209     return free_slots;
210 }
211 
212 int hci_can_send_packet_now(uint8_t packet_type){
213 
214     // check for async hci transport implementations
215     if (hci_stack.hci_transport->can_send_packet_now){
216         if (!hci_stack.hci_transport->can_send_packet_now(packet_type)){
217             return 0;
218         }
219     }
220 
221     // check regular Bluetooth flow control
222     switch (packet_type) {
223         case HCI_ACL_DATA_PACKET:
224             return hci_number_free_acl_slots();
225         case HCI_COMMAND_DATA_PACKET:
226             return hci_stack.num_cmd_packets;
227         default:
228             return 0;
229     }
230 }
231 
232 int hci_send_acl_packet(uint8_t *packet, int size){
233 
234     // check for free places on BT module
235     if (!hci_number_free_acl_slots()) return BTSTACK_ACL_BUFFERS_FULL;
236 
237     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
238     hci_connection_t *connection = connection_for_handle( con_handle);
239     if (!connection) return 0;
240     hci_connection_timestamp(connection);
241 
242     // count packet
243     connection->num_acl_packets_sent++;
244     // log_info("hci_send_acl_packet - handle %u, sent %u\n", connection->con_handle, connection->num_acl_packets_sent);
245 
246     // send packet
247     int err = hci_stack.hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
248 
249     return err;
250 }
251 
252 static void acl_handler(uint8_t *packet, int size){
253 
254     // get info
255     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
256     hci_connection_t *conn      = connection_for_handle(con_handle);
257     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
258     uint16_t acl_length         = READ_ACL_LENGTH(packet);
259 
260     // ignore non-registered handle
261     if (!conn){
262         log_error( "hci.c: acl_handler called with non-registered handle %u!\n" , con_handle);
263         return;
264     }
265 
266     // update idle timestamp
267     hci_connection_timestamp(conn);
268 
269     // handle different packet types
270     switch (acl_flags & 0x03) {
271 
272         case 0x01: // continuation fragment
273 
274             // sanity check
275             if (conn->acl_recombination_pos == 0) {
276                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x\n", con_handle);
277                 return;
278             }
279 
280             // append fragment payload (header already stored)
281             memcpy(&conn->acl_recombination_buffer[conn->acl_recombination_pos], &packet[4], acl_length );
282             conn->acl_recombination_pos += acl_length;
283 
284             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u\n", acl_length,
285             //        conn->acl_recombination_pos, conn->acl_recombination_length);
286 
287             // forward complete L2CAP packet if complete.
288             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
289 
290                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, conn->acl_recombination_buffer, conn->acl_recombination_pos);
291                 // reset recombination buffer
292                 conn->acl_recombination_length = 0;
293                 conn->acl_recombination_pos = 0;
294             }
295             break;
296 
297         case 0x02: { // first fragment
298 
299             // sanity check
300             if (conn->acl_recombination_pos) {
301                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x\n", con_handle);
302                 return;
303             }
304 
305             // peek into L2CAP packet!
306             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
307 
308             // log_error( "ACL First Fragment: acl_len %u, l2cap_len %u\n", acl_length, l2cap_length);
309 
310             // compare fragment size to L2CAP packet size
311             if (acl_length >= l2cap_length + 4){
312 
313                 // forward fragment as L2CAP packet
314                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, packet, acl_length + 4);
315 
316             } else {
317                 // store first fragment and tweak acl length for complete package
318                 memcpy(conn->acl_recombination_buffer, packet, acl_length + 4);
319                 conn->acl_recombination_pos    = acl_length + 4;
320                 conn->acl_recombination_length = l2cap_length;
321                 bt_store_16(conn->acl_recombination_buffer, 2, l2cap_length +4);
322             }
323             break;
324 
325         }
326         default:
327             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u\n", acl_flags & 0x03);
328             return;
329     }
330 
331     // execute main loop
332     hci_run();
333 }
334 
335 static void hci_shutdown_connection(hci_connection_t *conn){
336     log_info("Connection closed: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
337 
338     // cancel all l2cap connections
339     hci_emit_disconnection_complete(conn->con_handle, 0x16);    // terminated by local host
340 
341     run_loop_remove_timer(&conn->timeout);
342 
343     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
344     btstack_memory_hci_connection_free( conn );
345 
346     // now it's gone
347     hci_emit_nr_connections_changed();
348 }
349 
350 static const uint16_t packet_type_sizes[] = {
351     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
352     HCI_ACL_DH1_SIZE, 0, 0, 0,
353     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
354     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
355 };
356 
357 static uint16_t hci_acl_packet_types_for_buffer_size(uint16_t buffer_size){
358     uint16_t packet_types = 0;
359     int i;
360     for (i=0;i<16;i++){
361         if (packet_type_sizes[i] == 0) continue;
362         if (packet_type_sizes[i] <= buffer_size){
363             packet_types |= 1 << i;
364         }
365     }
366     // flip bits for "may not be used"
367     packet_types ^= 0x3306;
368     return packet_types;
369 }
370 
371 uint16_t hci_usable_acl_packet_types(void){
372     return hci_stack.packet_types;
373 }
374 
375 uint8_t* hci_get_outgoing_acl_packet_buffer(void){
376     // hci packet buffer is >= acl data packet length
377     return hci_stack.hci_packet_buffer;
378 }
379 
380 uint16_t hci_max_acl_data_packet_length(){
381     return hci_stack.acl_data_packet_length;
382 }
383 
384 // avoid huge local variables
385 #ifndef EMBEDDED
386 static device_name_t device_name;
387 #endif
388 static void event_handler(uint8_t *packet, int size){
389     bd_addr_t addr;
390     uint8_t link_type;
391     hci_con_handle_t handle;
392     hci_connection_t * conn;
393     int i;
394 
395     switch (packet[0]) {
396 
397         case HCI_EVENT_COMMAND_COMPLETE:
398             // get num cmd packets
399             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u\n", hci_stack.num_cmd_packets, packet[2]);
400             hci_stack.num_cmd_packets = packet[2];
401 
402             if (COMMAND_COMPLETE_EVENT(packet, hci_read_buffer_size)){
403                 // from offset 5
404                 // status
405                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
406                 hci_stack.acl_data_packet_length = READ_BT_16(packet, 6);
407                 // ignore: SCO data packet len (8)
408                 hci_stack.total_num_acl_packets  = packet[9];
409                 // ignore: total num SCO packets
410                 if (hci_stack.state == HCI_STATE_INITIALIZING){
411                     // determine usable ACL payload size
412                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack.acl_data_packet_length){
413                         hci_stack.acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
414                     }
415                     // determine usable ACL packet types
416                     hci_stack.packet_types = hci_acl_packet_types_for_buffer_size(hci_stack.acl_data_packet_length);
417 
418                     log_error("hci_read_buffer_size: used size %u, count %u, packet types %04x\n",
419                              hci_stack.acl_data_packet_length, hci_stack.total_num_acl_packets, hci_stack.packet_types);
420                 }
421             }
422             if (COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
423                 hci_emit_discoverable_enabled(hci_stack.discoverable);
424             }
425             break;
426 
427         case HCI_EVENT_COMMAND_STATUS:
428             // get num cmd packets
429             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u\n", hci_stack.num_cmd_packets, packet[3]);
430             hci_stack.num_cmd_packets = packet[3];
431             break;
432 
433         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:
434             for (i=0; i<packet[2];i++){
435                 handle = READ_BT_16(packet, 3 + 2*i);
436                 uint16_t num_packets = READ_BT_16(packet, 3 + packet[2]*2 + 2*i);
437                 conn = connection_for_handle(handle);
438                 if (!conn){
439                     log_error("hci_number_completed_packet lists unused con handle %u\n", handle);
440                     continue;
441                 }
442                 conn->num_acl_packets_sent -= num_packets;
443                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u\n", num_packets, handle, conn->num_acl_packets_sent);
444             }
445             break;
446 
447         case HCI_EVENT_CONNECTION_REQUEST:
448             bt_flip_addr(addr, &packet[2]);
449             // TODO: eval COD 8-10
450             link_type = packet[11];
451             log_info("Connection_incoming: %s, type %u\n", bd_addr_to_str(addr), link_type);
452             if (link_type == 1) { // ACL
453                 conn = connection_for_address(addr);
454                 if (!conn) {
455                     conn = create_connection_for_addr(addr);
456                 }
457                 if (!conn) {
458                     // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
459                     hci_stack.decline_reason = 0x0d;
460                     BD_ADDR_COPY(hci_stack.decline_addr, addr);
461                     break;
462                 }
463                 conn->state = RECEIVED_CONNECTION_REQUEST;
464                 hci_run();
465             } else {
466                 // SYNCHRONOUS CONNECTION LIMIT TO A DEVICE EXCEEDED (0X0A)
467                 hci_stack.decline_reason = 0x0a;
468                 BD_ADDR_COPY(hci_stack.decline_addr, addr);
469             }
470             break;
471 
472         case HCI_EVENT_CONNECTION_COMPLETE:
473             // Connection management
474             bt_flip_addr(addr, &packet[5]);
475             log_info("Connection_complete (status=%u) %s\n", packet[2], bd_addr_to_str(addr));
476             conn = connection_for_address(addr);
477             if (conn) {
478                 if (!packet[2]){
479                     conn->state = OPEN;
480                     conn->con_handle = READ_BT_16(packet, 3);
481 
482                     // restart timer
483                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
484                     run_loop_add_timer(&conn->timeout);
485 
486                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
487 
488                     hci_emit_nr_connections_changed();
489                 } else {
490                     // connection failed, remove entry
491                     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
492                     btstack_memory_hci_connection_free( conn );
493 
494                     // if authentication error, also delete link key
495                     if (packet[2] == 0x05) {
496                         hci_drop_link_key_for_bd_addr(&addr);
497                     }
498                 }
499             }
500             break;
501 
502         case HCI_EVENT_LINK_KEY_REQUEST:
503             log_info("HCI_EVENT_LINK_KEY_REQUEST\n");
504             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
505             if (!hci_stack.remote_device_db) break;
506             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
507             hci_run();
508             // request already answered
509             return;
510 
511         case HCI_EVENT_LINK_KEY_NOTIFICATION:
512             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_NOTIFICATION);
513             if (!hci_stack.remote_device_db) break;
514             bt_flip_addr(addr, &packet[2]);
515             hci_stack.remote_device_db->put_link_key(&addr, (link_key_t *) &packet[8]);
516             // still forward event to allow dismiss of pairing dialog
517             break;
518 
519         case HCI_EVENT_PIN_CODE_REQUEST:
520             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_PIN_CODE_REQUEST);
521             break;
522 
523 #ifndef EMBEDDED
524         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
525             if (!hci_stack.remote_device_db) break;
526             if (packet[2]) break; // status not ok
527             bt_flip_addr(addr, &packet[3]);
528             // fix for invalid remote names - terminate on 0xff
529             for (i=0; i<248;i++){
530                 if (packet[9+i] == 0xff){
531                     packet[9+i] = 0;
532                     break;
533                 }
534             }
535             memset(&device_name, 0, sizeof(device_name_t));
536             strncpy((char*) device_name, (char*) &packet[9], 248);
537             hci_stack.remote_device_db->put_name(&addr, &device_name);
538             break;
539 
540         case HCI_EVENT_INQUIRY_RESULT:
541         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
542             if (!hci_stack.remote_device_db) break;
543             // first send inq result packet
544             hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
545             // then send cached remote names
546             for (i=0; i<packet[2];i++){
547                 bt_flip_addr(addr, &packet[3+i*6]);
548                 if (hci_stack.remote_device_db->get_name(&addr, &device_name)){
549                     hci_emit_remote_name_cached(&addr, &device_name);
550                 }
551             }
552             return;
553 #endif
554 
555         case HCI_EVENT_DISCONNECTION_COMPLETE:
556             if (!packet[2]){
557                 handle = READ_BT_16(packet, 3);
558                 hci_connection_t * conn = connection_for_handle(handle);
559                 if (conn) {
560                     hci_shutdown_connection(conn);
561                 }
562             }
563             break;
564 
565         case HCI_EVENT_HARDWARE_ERROR:
566             if(hci_stack.control->hw_error){
567                 (*hci_stack.control->hw_error)();
568             }
569             break;
570 
571         default:
572             break;
573     }
574 
575     // handle BT initialization
576     if (hci_stack.state == HCI_STATE_INITIALIZING){
577         // handle H4 synchronization loss on restart
578         // if (hci_stack.substate == 1 && packet[0] == HCI_EVENT_HARDWARE_ERROR){
579         //    hci_stack.substate = 0;
580         // }
581         // handle normal init sequence
582         if (hci_stack.substate % 2){
583             // odd: waiting for event
584             if (packet[0] == HCI_EVENT_COMMAND_COMPLETE){
585                 hci_stack.substate++;
586             }
587         }
588     }
589 
590     // help with BT sleep
591     if (hci_stack.state == HCI_STATE_FALLING_ASLEEP
592         && hci_stack.substate == 1
593         && COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
594         hci_stack.substate++;
595     }
596 
597     hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
598 
599 	// execute main loop
600 	hci_run();
601 }
602 
603 void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
604     switch (packet_type) {
605         case HCI_EVENT_PACKET:
606             event_handler(packet, size);
607             break;
608         case HCI_ACL_DATA_PACKET:
609             acl_handler(packet, size);
610             break;
611         default:
612             break;
613     }
614 }
615 
616 /** Register HCI packet handlers */
617 void hci_register_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
618     hci_stack.packet_handler = handler;
619 }
620 
621 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control, remote_device_db_t * remote_device_db){
622 
623     // reference to use transport layer implementation
624     hci_stack.hci_transport = transport;
625 
626     // references to used control implementation
627     hci_stack.control = control;
628 
629     // reference to used config
630     hci_stack.config = config;
631 
632     // no connections yet
633     hci_stack.connections = NULL;
634     hci_stack.discoverable = 0;
635 
636     // no pending cmds
637     hci_stack.decline_reason = 0;
638     hci_stack.new_scan_enable_value = 0xff;
639 
640     // higher level handler
641     hci_stack.packet_handler = dummy_handler;
642 
643     // store and open remote device db
644     hci_stack.remote_device_db = remote_device_db;
645     if (hci_stack.remote_device_db) {
646         hci_stack.remote_device_db->open();
647     }
648 
649     // max acl payload size defined in config.h
650     hci_stack.acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
651 
652     // register packet handlers with transport
653     transport->register_packet_handler(&packet_handler);
654 }
655 
656 void hci_close(){
657     // close remote device db
658     if (hci_stack.remote_device_db) {
659         hci_stack.remote_device_db->close();
660     }
661 }
662 
663 // State-Module-Driver overview
664 // state                    module  low-level
665 // HCI_STATE_OFF             off      close
666 // HCI_STATE_INITIALIZING,   on       open
667 // HCI_STATE_WORKING,        on       open
668 // HCI_STATE_HALTING,        on       open
669 // HCI_STATE_SLEEPING,    off/sleep   close
670 // HCI_STATE_FALLING_ASLEEP  on       open
671 
672 static int hci_power_control_on(void){
673 
674     // power on
675     int err = 0;
676     if (hci_stack.control && hci_stack.control->on){
677         err = (*hci_stack.control->on)(hci_stack.config);
678     }
679     if (err){
680         log_error( "POWER_ON failed\n");
681         hci_emit_hci_open_failed();
682         return err;
683     }
684 
685     // open low-level device
686     err = hci_stack.hci_transport->open(hci_stack.config);
687     if (err){
688         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
689         if (hci_stack.control && hci_stack.control->off){
690             (*hci_stack.control->off)(hci_stack.config);
691         }
692         hci_emit_hci_open_failed();
693         return err;
694     }
695     return 0;
696 }
697 
698 static void hci_power_control_off(void){
699 
700     log_info("hci_power_control_off\n");
701 
702     // close low-level device
703     hci_stack.hci_transport->close(hci_stack.config);
704 
705     log_info("hci_power_control_off - hci_transport closed\n");
706 
707     // power off
708     if (hci_stack.control && hci_stack.control->off){
709         (*hci_stack.control->off)(hci_stack.config);
710     }
711 
712     log_info("hci_power_control_off - control closed\n");
713 
714     hci_stack.state = HCI_STATE_OFF;
715 }
716 
717 static void hci_power_control_sleep(void){
718 
719     log_info("hci_power_control_sleep\n");
720 
721 #if 0
722     // don't close serial port during sleep
723 
724     // close low-level device
725     hci_stack.hci_transport->close(hci_stack.config);
726 #endif
727 
728     // sleep mode
729     if (hci_stack.control && hci_stack.control->sleep){
730         (*hci_stack.control->sleep)(hci_stack.config);
731     }
732 
733     hci_stack.state = HCI_STATE_SLEEPING;
734 }
735 
736 static int hci_power_control_wake(void){
737 
738     log_info("hci_power_control_wake\n");
739 
740     // wake on
741     if (hci_stack.control && hci_stack.control->wake){
742         (*hci_stack.control->wake)(hci_stack.config);
743     }
744 
745 #if 0
746     // open low-level device
747     int err = hci_stack.hci_transport->open(hci_stack.config);
748     if (err){
749         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
750         if (hci_stack.control && hci_stack.control->off){
751             (*hci_stack.control->off)(hci_stack.config);
752         }
753         hci_emit_hci_open_failed();
754         return err;
755     }
756 #endif
757 
758     return 0;
759 }
760 
761 
762 int hci_power_control(HCI_POWER_MODE power_mode){
763 
764     log_info("hci_power_control: %u, current mode %u\n", power_mode, hci_stack.state);
765 
766     int err = 0;
767     switch (hci_stack.state){
768 
769         case HCI_STATE_OFF:
770             switch (power_mode){
771                 case HCI_POWER_ON:
772                     err = hci_power_control_on();
773                     if (err) return err;
774                     // set up state machine
775                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
776                     hci_stack.state = HCI_STATE_INITIALIZING;
777                     hci_stack.substate = 0;
778                     break;
779                 case HCI_POWER_OFF:
780                     // do nothing
781                     break;
782                 case HCI_POWER_SLEEP:
783                     // do nothing (with SLEEP == OFF)
784                     break;
785             }
786             break;
787 
788         case HCI_STATE_INITIALIZING:
789             switch (power_mode){
790                 case HCI_POWER_ON:
791                     // do nothing
792                     break;
793                 case HCI_POWER_OFF:
794                     // no connections yet, just turn it off
795                     hci_power_control_off();
796                     break;
797                 case HCI_POWER_SLEEP:
798                     // no connections yet, just turn it off
799                     hci_power_control_sleep();
800                     break;
801             }
802             break;
803 
804         case HCI_STATE_WORKING:
805             switch (power_mode){
806                 case HCI_POWER_ON:
807                     // do nothing
808                     break;
809                 case HCI_POWER_OFF:
810                     // see hci_run
811                     hci_stack.state = HCI_STATE_HALTING;
812                     break;
813                 case HCI_POWER_SLEEP:
814                     // see hci_run
815                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
816                     hci_stack.substate = 0;
817                     break;
818             }
819             break;
820 
821         case HCI_STATE_HALTING:
822             switch (power_mode){
823                 case HCI_POWER_ON:
824                     // set up state machine
825                     hci_stack.state = HCI_STATE_INITIALIZING;
826                     hci_stack.substate = 0;
827                     break;
828                 case HCI_POWER_OFF:
829                     // do nothing
830                     break;
831                 case HCI_POWER_SLEEP:
832                     // see hci_run
833                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
834                     hci_stack.substate = 0;
835                     break;
836             }
837             break;
838 
839         case HCI_STATE_FALLING_ASLEEP:
840             switch (power_mode){
841                 case HCI_POWER_ON:
842                     // set up state machine
843                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
844                     hci_stack.state = HCI_STATE_INITIALIZING;
845                     hci_stack.substate = 0;
846                     break;
847                 case HCI_POWER_OFF:
848                     // see hci_run
849                     hci_stack.state = HCI_STATE_HALTING;
850                     break;
851                 case HCI_POWER_SLEEP:
852                     // do nothing
853                     break;
854             }
855             break;
856 
857         case HCI_STATE_SLEEPING:
858             switch (power_mode){
859                 case HCI_POWER_ON:
860                     err = hci_power_control_wake();
861                     if (err) return err;
862                     // set up state machine
863                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
864                     hci_stack.state = HCI_STATE_INITIALIZING;
865                     hci_stack.substate = 0;
866                     break;
867                 case HCI_POWER_OFF:
868                     hci_stack.state = HCI_STATE_HALTING;
869                     break;
870                 case HCI_POWER_SLEEP:
871                     // do nothing
872                     break;
873             }
874             break;
875     }
876 
877     // create internal event
878 	hci_emit_state();
879 
880 	// trigger next/first action
881 	hci_run();
882 
883     return 0;
884 }
885 
886 void hci_discoverable_control(uint8_t enable){
887     if (enable) enable = 1; // normalize argument
888 
889     if (hci_stack.discoverable == enable){
890         hci_emit_discoverable_enabled(hci_stack.discoverable);
891         return;
892     }
893 
894     // store request to send command but accept in higher layer view
895     hci_stack.new_scan_enable_value = 2 | enable; // 1 = inq scan, 2 = page scan
896     hci_stack.discoverable = enable;
897 
898     hci_run();
899 }
900 
901 void hci_run(){
902 
903     hci_connection_t * connection;
904     linked_item_t * it;
905 
906     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
907 
908     // global/non-connection oriented commands
909 
910     // decline incoming connections
911     if (hci_stack.decline_reason){
912         uint8_t reason = hci_stack.decline_reason;
913         hci_stack.decline_reason = 0;
914         hci_send_cmd(&hci_reject_connection_request, hci_stack.decline_addr, reason);
915     }
916 
917     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
918 
919     // send scan enable
920     if (hci_stack.new_scan_enable_value != 0xff){
921         hci_send_cmd(&hci_write_scan_enable, hci_stack.new_scan_enable_value);
922         hci_stack.new_scan_enable_value = 0xff;
923     }
924 
925     // send pending HCI commands
926     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
927 
928         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
929 
930         connection = (hci_connection_t *) it;
931 
932         if (connection->state == RECEIVED_CONNECTION_REQUEST){
933             log_info("sending hci_accept_connection_request\n");
934             hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
935             connection->state = ACCEPTED_CONNECTION_REQUEST;
936         }
937 
938         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
939 
940         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
941             link_key_t link_key;
942             log_info("responding to link key request\n");
943             if ( hci_stack.remote_device_db->get_link_key( &connection->address, &link_key)){
944                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
945             } else {
946                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
947             }
948             connection->authentication_flags &= ~HANDLE_LINK_KEY_REQUEST;
949         }
950     }
951 
952     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
953 
954     switch (hci_stack.state){
955         case HCI_STATE_INITIALIZING:
956             // log_info("hci_init: substate %u\n", hci_stack.substate);
957             if (hci_stack.substate % 2) {
958                 // odd: waiting for command completion
959                 return;
960             }
961             switch (hci_stack.substate >> 1){
962                 case 0: // RESET
963                     hci_send_cmd(&hci_reset);
964                     if (hci_stack.config == 0 || ((hci_uart_config_t *)hci_stack.config)->baudrate_main == 0){
965                         // skip baud change
966                         hci_stack.substate = 4; // >> 1 = 2
967                     }
968                     break;
969                 case 1: // SEND BAUD CHANGE
970                     hci_stack.control->baudrate_cmd(hci_stack.config, ((hci_uart_config_t *)hci_stack.config)->baudrate_main, hci_stack.hci_packet_buffer);
971                     hci_send_cmd_packet(hci_stack.hci_packet_buffer, 3 + hci_stack.hci_packet_buffer[2]);
972                     break;
973                 case 2: // LOCAL BAUD CHANGE
974                     hci_stack.hci_transport->set_baudrate(((hci_uart_config_t *)hci_stack.config)->baudrate_main);
975                     hci_stack.substate += 2;
976                     // break missing here for fall through
977 
978                 case 3:
979                     // custom initialization
980                     if (hci_stack.control && hci_stack.control->next_cmd){
981                         int valid_cmd = (*hci_stack.control->next_cmd)(hci_stack.config, hci_stack.hci_packet_buffer);
982                         if (valid_cmd){
983                             int size = 3 + hci_stack.hci_packet_buffer[2];
984                             hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack.hci_packet_buffer, size);
985                             hci_stack.substate = 4; // more init commands
986                             break;
987                         }
988                         log_info("hci_run: init script done\n\r");
989                     }
990                     // otherwise continue
991 					hci_send_cmd(&hci_read_bd_addr);
992 					break;
993 				case 4:
994 					hci_send_cmd(&hci_read_buffer_size);
995 					break;
996                 case 5:
997                     // ca. 15 sec
998                     hci_send_cmd(&hci_write_page_timeout, 0x6000);
999                     break;
1000 				case 6:
1001 					hci_send_cmd(&hci_write_scan_enable, 2 | hci_stack.discoverable); // page scan
1002 					break;
1003                 case 7:
1004 #ifndef EMBEDDED
1005                 {
1006                     char hostname[30];
1007                     gethostname(hostname, 30);
1008                     hostname[29] = '\0';
1009                     hci_send_cmd(&hci_write_local_name, hostname);
1010                     break;
1011                 }
1012                 case 8:
1013 #ifdef USE_BLUETOOL
1014                     hci_send_cmd(&hci_write_class_of_device, 0x007a020c); // Smartphone
1015                     break;
1016 
1017                 case 9:
1018 #endif
1019 #endif
1020                     // done.
1021                     hci_stack.state = HCI_STATE_WORKING;
1022                     hci_emit_state();
1023                     break;
1024                 default:
1025                     break;
1026             }
1027             hci_stack.substate++;
1028             break;
1029 
1030         case HCI_STATE_HALTING:
1031 
1032             log_info("HCI_STATE_HALTING\n");
1033             // close all open connections
1034             connection =  (hci_connection_t *) hci_stack.connections;
1035             if (connection){
1036 
1037                 // send disconnect
1038                 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1039 
1040                 log_info("HCI_STATE_HALTING, connection %lu, handle %u\n", (uintptr_t) connection, (uint16_t)connection->con_handle);
1041                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1042 
1043                 // send disconnected event right away - causes higher layer connections to get closed, too.
1044                 hci_shutdown_connection(connection);
1045                 return;
1046             }
1047             log_info("HCI_STATE_HALTING, calling off\n");
1048 
1049             // switch mode
1050             hci_power_control_off();
1051 
1052             log_info("HCI_STATE_HALTING, emitting state\n");
1053             hci_emit_state();
1054             log_info("HCI_STATE_HALTING, done\n");
1055             break;
1056 
1057         case HCI_STATE_FALLING_ASLEEP:
1058             switch(hci_stack.substate) {
1059                 case 0:
1060                     log_info("HCI_STATE_FALLING_ASLEEP\n");
1061                     // close all open connections
1062                     connection =  (hci_connection_t *) hci_stack.connections;
1063                     if (connection){
1064 
1065                         // send disconnect
1066                         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1067 
1068                         log_info("HCI_STATE_FALLING_ASLEEP, connection %lu, handle %u\n", (uintptr_t) connection, (uint16_t)connection->con_handle);
1069                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1070 
1071                         // send disconnected event right away - causes higher layer connections to get closed, too.
1072                         hci_shutdown_connection(connection);
1073                         return;
1074                     }
1075 
1076                     // disable page and inquiry scan
1077                     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1078 
1079                     log_info("HCI_STATE_HALTING, disabling inq & page scans\n");
1080                     hci_send_cmd(&hci_write_scan_enable, 0); // none
1081 
1082                     // continue in next sub state
1083                     hci_stack.substate++;
1084                     break;
1085                 case 1:
1086                     // wait for command complete "hci_write_scan_enable" in event_handler();
1087                     break;
1088                 case 2:
1089                     log_info("HCI_STATE_HALTING, calling sleep\n");
1090                     // switch mode
1091                     hci_power_control_sleep();  // changes hci_stack.state to SLEEP
1092                     hci_emit_state();
1093                 default:
1094                     break;
1095             }
1096             break;
1097 
1098         default:
1099             break;
1100     }
1101 }
1102 
1103 int hci_send_cmd_packet(uint8_t *packet, int size){
1104     bd_addr_t addr;
1105     hci_connection_t * conn;
1106     // house-keeping
1107 
1108     // create_connection?
1109     if (IS_COMMAND(packet, hci_create_connection)){
1110         bt_flip_addr(addr, &packet[3]);
1111         log_info("Create_connection to %s\n", bd_addr_to_str(addr));
1112         conn = connection_for_address(addr);
1113         if (conn) {
1114             // if connection exists
1115             if (conn->state == OPEN) {
1116                 // and OPEN, emit connection complete command
1117                 hci_emit_connection_complete(conn, 0);
1118             }
1119             //    otherwise, just ignore as it is already in the open process
1120             return 0; // don't sent packet to controller
1121 
1122         }
1123         // create connection struct and register, state = SENT_CREATE_CONNECTION
1124         conn = create_connection_for_addr(addr);
1125         if (!conn){
1126             // notify client that alloc failed
1127             hci_emit_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
1128             return 0; // don't sent packet to controller
1129         }
1130         conn->state = SENT_CREATE_CONNECTION;
1131     }
1132 
1133     if (IS_COMMAND(packet, hci_link_key_request_reply)){
1134         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
1135     }
1136     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
1137         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
1138     }
1139     if (IS_COMMAND(packet, hci_pin_code_request_reply)){
1140         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_REPLY);
1141     }
1142     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)){
1143         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_NEGATIVE_REPLY);
1144     }
1145 
1146     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
1147         if (hci_stack.remote_device_db){
1148             bt_flip_addr(addr, &packet[3]);
1149             hci_stack.remote_device_db->delete_link_key(&addr);
1150         }
1151     }
1152 
1153     hci_stack.num_cmd_packets--;
1154     return hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
1155 }
1156 
1157 /**
1158  * pre: numcmds >= 0 - it's allowed to send a command to the controller
1159  */
1160 int hci_send_cmd(const hci_cmd_t *cmd, ...){
1161     va_list argptr;
1162     va_start(argptr, cmd);
1163     uint16_t size = hci_create_cmd_internal(hci_stack.hci_packet_buffer, cmd, argptr);
1164     va_end(argptr);
1165     return hci_send_cmd_packet(hci_stack.hci_packet_buffer, size);
1166 }
1167 
1168 // Create various non-HCI events.
1169 // TODO: generalize, use table similar to hci_create_command
1170 
1171 void hci_emit_state(){
1172     uint8_t event[3];
1173     event[0] = BTSTACK_EVENT_STATE;
1174     event[1] = sizeof(event) - 2;
1175     event[2] = hci_stack.state;
1176     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1177     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1178 }
1179 
1180 void hci_emit_connection_complete(hci_connection_t *conn, uint8_t status){
1181     uint8_t event[13];
1182     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
1183     event[1] = sizeof(event) - 2;
1184     event[2] = status;
1185     bt_store_16(event, 3, conn->con_handle);
1186     bt_flip_addr(&event[5], conn->address);
1187     event[11] = 1; // ACL connection
1188     event[12] = 0; // encryption disabled
1189     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1190     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1191 }
1192 
1193 void hci_emit_disconnection_complete(uint16_t handle, uint8_t reason){
1194     uint8_t event[6];
1195     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
1196     event[1] = sizeof(event) - 2;
1197     event[2] = 0; // status = OK
1198     bt_store_16(event, 3, handle);
1199     event[5] = reason;
1200     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1201     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1202 }
1203 
1204 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
1205     uint8_t event[4];
1206     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
1207     event[1] = sizeof(event) - 2;
1208     bt_store_16(event, 2, conn->con_handle);
1209     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1210     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1211 }
1212 
1213 void hci_emit_nr_connections_changed(){
1214     uint8_t event[3];
1215     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
1216     event[1] = sizeof(event) - 2;
1217     event[2] = nr_hci_connections();
1218     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1219     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1220 }
1221 
1222 void hci_emit_hci_open_failed(){
1223     uint8_t event[2];
1224     event[0] = BTSTACK_EVENT_POWERON_FAILED;
1225     event[1] = sizeof(event) - 2;
1226     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1227     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1228 }
1229 
1230 
1231 void hci_emit_btstack_version() {
1232     uint8_t event[6];
1233     event[0] = BTSTACK_EVENT_VERSION;
1234     event[1] = sizeof(event) - 2;
1235     event[2] = BTSTACK_MAJOR;
1236     event[3] = BTSTACK_MINOR;
1237     bt_store_16(event, 4, BTSTACK_REVISION);
1238     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1239     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1240 }
1241 
1242 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
1243     uint8_t event[3];
1244     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
1245     event[1] = sizeof(event) - 2;
1246     event[2] = enabled;
1247     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1248     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1249 }
1250 
1251 void hci_emit_remote_name_cached(bd_addr_t *addr, device_name_t *name){
1252     uint8_t event[2+1+6+248];
1253     event[0] = BTSTACK_EVENT_REMOTE_NAME_CACHED;
1254     event[1] = sizeof(event) - 2;
1255     event[2] = 0;   // just to be compatible with HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
1256     bt_flip_addr(&event[3], *addr);
1257     memcpy(&event[9], name, 248);
1258     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1259     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1260 }
1261 
1262 void hci_emit_discoverable_enabled(uint8_t enabled){
1263     uint8_t event[3];
1264     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
1265     event[1] = sizeof(event) - 2;
1266     event[2] = enabled;
1267     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1268     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1269 }
1270