xref: /btstack/src/hci.c (revision 1d6b20ae69e08539c0afd1c6ac325f9db54ad1ea)
1 /*
2  * Copyright (C) 2009-2012 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  * 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 MATTHIAS RINGWALD 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 [email protected]
34  *
35  */
36 
37 /*
38  *  hci.c
39  *
40  *  Created by Matthias Ringwald on 4/29/09.
41  *
42  */
43 
44 #include "config.h"
45 
46 #include "hci.h"
47 
48 #include <stdarg.h>
49 #include <string.h>
50 #include <stdio.h>
51 
52 #ifndef EMBEDDED
53 #include <unistd.h> // gethostbyname
54 #include <btstack/version.h>
55 #endif
56 
57 #include "btstack_memory.h"
58 #include "debug.h"
59 #include "hci_dump.h"
60 
61 #include <btstack/hci_cmds.h>
62 
63 #define HCI_CONNECTION_TIMEOUT_MS 10000
64 
65 #define HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP 11
66 
67 #ifdef USE_BLUETOOL
68 #include "bt_control_iphone.h"
69 #endif
70 
71 static void hci_update_scan_enable(void);
72 
73 // the STACK is here
74 static hci_stack_t       hci_stack;
75 
76 /**
77  * get connection for a given handle
78  *
79  * @return connection OR NULL, if not found
80  */
81 hci_connection_t * connection_for_handle(hci_con_handle_t con_handle){
82     linked_item_t *it;
83     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
84         if ( ((hci_connection_t *) it)->con_handle == con_handle){
85             return (hci_connection_t *) it;
86         }
87     }
88     return NULL;
89 }
90 
91 static void hci_connection_timeout_handler(timer_source_t *timer){
92     hci_connection_t * connection = (hci_connection_t *) linked_item_get_user(&timer->item);
93 #ifdef HAVE_TIME
94     struct timeval tv;
95     gettimeofday(&tv, NULL);
96     if (tv.tv_sec >= connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000) {
97         // connections might be timed out
98         hci_emit_l2cap_check_timeout(connection);
99     }
100 #endif
101 #ifdef HAVE_TICK
102     if (embedded_get_ticks() > connection->timestamp + embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
103         // connections might be timed out
104         hci_emit_l2cap_check_timeout(connection);
105     }
106 #endif
107     run_loop_set_timer(timer, HCI_CONNECTION_TIMEOUT_MS);
108     run_loop_add_timer(timer);
109 }
110 
111 static void hci_connection_timestamp(hci_connection_t *connection){
112 #ifdef HAVE_TIME
113     gettimeofday(&connection->timestamp, NULL);
114 #endif
115 #ifdef HAVE_TICK
116     connection->timestamp = embedded_get_ticks();
117 #endif
118 }
119 
120 /**
121  * create connection for given address
122  *
123  * @return connection OR NULL, if no memory left
124  */
125 static hci_connection_t * create_connection_for_addr(bd_addr_t addr){
126     hci_connection_t * conn = (hci_connection_t *) btstack_memory_hci_connection_get();
127     if (!conn) return NULL;
128     BD_ADDR_COPY(conn->address, addr);
129     conn->con_handle = 0xffff;
130     conn->authentication_flags = AUTH_FLAGS_NONE;
131     linked_item_set_user(&conn->timeout.item, conn);
132     conn->timeout.process = hci_connection_timeout_handler;
133     hci_connection_timestamp(conn);
134     conn->acl_recombination_length = 0;
135     conn->acl_recombination_pos = 0;
136     conn->num_acl_packets_sent = 0;
137     linked_list_add(&hci_stack.connections, (linked_item_t *) conn);
138     return conn;
139 }
140 
141 /**
142  * get connection for given address
143  *
144  * @return connection OR NULL, if not found
145  */
146 static hci_connection_t * connection_for_address(bd_addr_t address){
147     linked_item_t *it;
148     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
149         if ( ! BD_ADDR_CMP( ((hci_connection_t *) it)->address, address) ){
150             return (hci_connection_t *) it;
151         }
152     }
153     return NULL;
154 }
155 
156 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
157     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
158 }
159 
160 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
161     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
162 }
163 
164 
165 /**
166  * add authentication flags and reset timer
167  */
168 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
169     bd_addr_t addr;
170     bt_flip_addr(addr, *(bd_addr_t *) bd_addr);
171     hci_connection_t * conn = connection_for_address(addr);
172     if (conn) {
173         connectionSetAuthenticationFlags(conn, flags);
174         hci_connection_timestamp(conn);
175     }
176 }
177 
178 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
179     hci_connection_t * conn = connection_for_handle(handle);
180     if (!conn) return 0;
181     if (!conn->authentication_flags) return 0;
182     if (conn->authentication_flags & SENT_LINK_KEY_REPLY) return 0;
183     if (conn->authentication_flags & RECV_LINK_KEY_NOTIFICATION) return 0;
184     return 1;
185 }
186 
187 void hci_drop_link_key_for_bd_addr(bd_addr_t *addr){
188     if (hci_stack.remote_device_db) {
189         hci_stack.remote_device_db->delete_link_key(addr);
190     }
191 }
192 
193 
194 /**
195  * count connections
196  */
197 static int nr_hci_connections(void){
198     int count = 0;
199     linked_item_t *it;
200     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next, count++);
201     return count;
202 }
203 
204 /**
205  * Dummy handler called by HCI
206  */
207 static void dummy_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
208 }
209 
210 uint8_t hci_number_outgoing_packets(hci_con_handle_t handle){
211     hci_connection_t * connection = connection_for_handle(handle);
212     if (!connection) {
213         log_error("hci_number_outgoing_packets connectino for handle %u does not exist!\n", handle);
214         return 0;
215     }
216     return connection->num_acl_packets_sent;
217 }
218 
219 uint8_t hci_number_free_acl_slots(){
220     uint8_t free_slots = hci_stack.total_num_acl_packets;
221     linked_item_t *it;
222     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
223         hci_connection_t * connection = (hci_connection_t *) it;
224         if (free_slots < connection->num_acl_packets_sent) {
225             log_error("hci_number_free_acl_slots: sum of outgoing packets > total acl packets!\n");
226             return 0;
227         }
228         free_slots -= connection->num_acl_packets_sent;
229     }
230     return free_slots;
231 }
232 
233 int hci_can_send_packet_now(uint8_t packet_type){
234 
235     // check for async hci transport implementations
236     if (hci_stack.hci_transport->can_send_packet_now){
237         if (!hci_stack.hci_transport->can_send_packet_now(packet_type)){
238             return 0;
239         }
240     }
241 
242     // check regular Bluetooth flow control
243     switch (packet_type) {
244         case HCI_ACL_DATA_PACKET:
245             return hci_number_free_acl_slots();
246         case HCI_COMMAND_DATA_PACKET:
247             return hci_stack.num_cmd_packets;
248         default:
249             return 0;
250     }
251 }
252 
253 int hci_send_acl_packet(uint8_t *packet, int size){
254 
255     // check for free places on BT module
256     if (!hci_number_free_acl_slots()) return BTSTACK_ACL_BUFFERS_FULL;
257 
258     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
259     hci_connection_t *connection = connection_for_handle( con_handle);
260     if (!connection) return 0;
261     hci_connection_timestamp(connection);
262 
263     // count packet
264     connection->num_acl_packets_sent++;
265     // log_info("hci_send_acl_packet - handle %u, sent %u\n", connection->con_handle, connection->num_acl_packets_sent);
266 
267     // send packet
268     int err = hci_stack.hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
269 
270     return err;
271 }
272 
273 static void acl_handler(uint8_t *packet, int size){
274 
275     // get info
276     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
277     hci_connection_t *conn      = connection_for_handle(con_handle);
278     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
279     uint16_t acl_length         = READ_ACL_LENGTH(packet);
280 
281     // ignore non-registered handle
282     if (!conn){
283         log_error( "hci.c: acl_handler called with non-registered handle %u!\n" , con_handle);
284         return;
285     }
286 
287     // update idle timestamp
288     hci_connection_timestamp(conn);
289 
290     // handle different packet types
291     switch (acl_flags & 0x03) {
292 
293         case 0x01: // continuation fragment
294 
295             // sanity check
296             if (conn->acl_recombination_pos == 0) {
297                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x\n", con_handle);
298                 return;
299             }
300 
301             // append fragment payload (header already stored)
302             memcpy(&conn->acl_recombination_buffer[conn->acl_recombination_pos], &packet[4], acl_length );
303             conn->acl_recombination_pos += acl_length;
304 
305             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u\n", acl_length,
306             //        conn->acl_recombination_pos, conn->acl_recombination_length);
307 
308             // forward complete L2CAP packet if complete.
309             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
310 
311                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, conn->acl_recombination_buffer, conn->acl_recombination_pos);
312                 // reset recombination buffer
313                 conn->acl_recombination_length = 0;
314                 conn->acl_recombination_pos = 0;
315             }
316             break;
317 
318         case 0x02: { // first fragment
319 
320             // sanity check
321             if (conn->acl_recombination_pos) {
322                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x\n", con_handle);
323                 return;
324             }
325 
326             // peek into L2CAP packet!
327             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
328 
329             // log_error( "ACL First Fragment: acl_len %u, l2cap_len %u\n", acl_length, l2cap_length);
330 
331             // compare fragment size to L2CAP packet size
332             if (acl_length >= l2cap_length + 4){
333 
334                 // forward fragment as L2CAP packet
335                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, packet, acl_length + 4);
336 
337             } else {
338                 // store first fragment and tweak acl length for complete package
339                 memcpy(conn->acl_recombination_buffer, packet, acl_length + 4);
340                 conn->acl_recombination_pos    = acl_length + 4;
341                 conn->acl_recombination_length = l2cap_length;
342                 bt_store_16(conn->acl_recombination_buffer, 2, l2cap_length +4);
343             }
344             break;
345 
346         }
347         default:
348             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u\n", acl_flags & 0x03);
349             return;
350     }
351 
352     // execute main loop
353     hci_run();
354 }
355 
356 static void hci_shutdown_connection(hci_connection_t *conn){
357     log_info("Connection closed: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
358 
359     // cancel all l2cap connections
360     hci_emit_disconnection_complete(conn->con_handle, 0x16);    // terminated by local host
361 
362     run_loop_remove_timer(&conn->timeout);
363 
364     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
365     btstack_memory_hci_connection_free( conn );
366 
367     // now it's gone
368     hci_emit_nr_connections_changed();
369 }
370 
371 static const uint16_t packet_type_sizes[] = {
372     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
373     HCI_ACL_DH1_SIZE, 0, 0, 0,
374     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
375     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
376 };
377 
378 static uint16_t hci_acl_packet_types_for_buffer_size(uint16_t buffer_size){
379     uint16_t packet_types = 0;
380     int i;
381     for (i=0;i<16;i++){
382         if (packet_type_sizes[i] == 0) continue;
383         if (packet_type_sizes[i] <= buffer_size){
384             packet_types |= 1 << i;
385         }
386     }
387     // flip bits for "may not be used"
388     packet_types ^= 0x3306;
389     return packet_types;
390 }
391 
392 uint16_t hci_usable_acl_packet_types(void){
393     return hci_stack.packet_types;
394 }
395 
396 uint8_t* hci_get_outgoing_acl_packet_buffer(void){
397     // hci packet buffer is >= acl data packet length
398     return hci_stack.hci_packet_buffer;
399 }
400 
401 uint16_t hci_max_acl_data_packet_length(){
402     return hci_stack.acl_data_packet_length;
403 }
404 
405 // avoid huge local variables
406 #ifndef EMBEDDED
407 static device_name_t device_name;
408 #endif
409 static void event_handler(uint8_t *packet, int size){
410     bd_addr_t addr;
411     uint8_t link_type;
412     hci_con_handle_t handle;
413     hci_connection_t * conn;
414     int i;
415 
416     // printf("HCI:EVENT:%02x\n", packet[0]);
417 
418     switch (packet[0]) {
419 
420         case HCI_EVENT_COMMAND_COMPLETE:
421             // get num cmd packets
422             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u\n", hci_stack.num_cmd_packets, packet[2]);
423             hci_stack.num_cmd_packets = packet[2];
424 
425             if (COMMAND_COMPLETE_EVENT(packet, hci_read_buffer_size)){
426                 // from offset 5
427                 // status
428                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
429                 hci_stack.acl_data_packet_length = READ_BT_16(packet, 6);
430                 // ignore: SCO data packet len (8)
431                 hci_stack.total_num_acl_packets  = packet[9];
432                 // ignore: total num SCO packets
433                 if (hci_stack.state == HCI_STATE_INITIALIZING){
434                     // determine usable ACL payload size
435                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack.acl_data_packet_length){
436                         hci_stack.acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
437                     }
438                     // determine usable ACL packet types
439                     hci_stack.packet_types = hci_acl_packet_types_for_buffer_size(hci_stack.acl_data_packet_length);
440 
441                     log_info("hci_read_buffer_size: used size %u, count %u, packet types %04x\n",
442                              hci_stack.acl_data_packet_length, hci_stack.total_num_acl_packets, hci_stack.packet_types);
443                 }
444             }
445             // Dump local address
446             if (COMMAND_COMPLETE_EVENT(packet, hci_read_bd_addr)) {
447                 bt_flip_addr(hci_stack.local_bd_addr, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1]);
448                 log_info("Local Address, Status: 0x%02x: Addr: %s\n",
449                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack.local_bd_addr));
450             }
451             if (COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
452                 hci_emit_discoverable_enabled(hci_stack.discoverable);
453             }
454             if (COMMAND_COMPLETE_EVENT(packet, hci_read_local_supported_features)){
455                 memcpy(hci_stack.local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], 8);
456                 log_info("Local Supported Features: 0x%02x%02x%02x%02x%02x%02x%02x%02x",
457                     hci_stack.local_supported_features[0], hci_stack.local_supported_features[1],
458                     hci_stack.local_supported_features[2], hci_stack.local_supported_features[3],
459                     hci_stack.local_supported_features[4], hci_stack.local_supported_features[5],
460                     hci_stack.local_supported_features[6], hci_stack.local_supported_features[7]);
461             }
462             break;
463 
464         case HCI_EVENT_COMMAND_STATUS:
465             // get num cmd packets
466             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u\n", hci_stack.num_cmd_packets, packet[3]);
467             hci_stack.num_cmd_packets = packet[3];
468             break;
469 
470         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:
471             for (i=0; i<packet[2];i++){
472                 handle = READ_BT_16(packet, 3 + 2*i);
473                 uint16_t num_packets = READ_BT_16(packet, 3 + packet[2]*2 + 2*i);
474                 conn = connection_for_handle(handle);
475                 if (!conn){
476                     log_error("hci_number_completed_packet lists unused con handle %u\n", handle);
477                     continue;
478                 }
479                 conn->num_acl_packets_sent -= num_packets;
480                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u\n", num_packets, handle, conn->num_acl_packets_sent);
481             }
482             break;
483 
484         case HCI_EVENT_CONNECTION_REQUEST:
485             bt_flip_addr(addr, &packet[2]);
486             // TODO: eval COD 8-10
487             link_type = packet[11];
488             log_info("Connection_incoming: %s, type %u\n", bd_addr_to_str(addr), link_type);
489             if (link_type == 1) { // ACL
490                 conn = connection_for_address(addr);
491                 if (!conn) {
492                     conn = create_connection_for_addr(addr);
493                 }
494                 if (!conn) {
495                     // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
496                     hci_stack.decline_reason = 0x0d;
497                     BD_ADDR_COPY(hci_stack.decline_addr, addr);
498                     break;
499                 }
500                 conn->state = RECEIVED_CONNECTION_REQUEST;
501                 hci_run();
502             } else {
503                 // SYNCHRONOUS CONNECTION LIMIT TO A DEVICE EXCEEDED (0X0A)
504                 hci_stack.decline_reason = 0x0a;
505                 BD_ADDR_COPY(hci_stack.decline_addr, addr);
506             }
507             break;
508 
509         case HCI_EVENT_CONNECTION_COMPLETE:
510             // Connection management
511             bt_flip_addr(addr, &packet[5]);
512             log_info("Connection_complete (status=%u) %s\n", packet[2], bd_addr_to_str(addr));
513             conn = connection_for_address(addr);
514             if (conn) {
515                 if (!packet[2]){
516                     conn->state = OPEN;
517                     conn->con_handle = READ_BT_16(packet, 3);
518 
519                     // restart timer
520                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
521                     run_loop_add_timer(&conn->timeout);
522 
523                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
524 
525                     hci_emit_nr_connections_changed();
526                 } else {
527                     // connection failed, remove entry
528                     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
529                     btstack_memory_hci_connection_free( conn );
530 
531                     // if authentication error, also delete link key
532                     if (packet[2] == 0x05) {
533                         hci_drop_link_key_for_bd_addr(&addr);
534                     }
535                 }
536             }
537             break;
538 
539         case HCI_EVENT_LINK_KEY_REQUEST:
540             log_info("HCI_EVENT_LINK_KEY_REQUEST\n");
541             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
542             if (!hci_stack.remote_device_db) break;
543             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
544             hci_run();
545             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
546             return;
547 
548         case HCI_EVENT_LINK_KEY_NOTIFICATION:
549             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_NOTIFICATION);
550             if (!hci_stack.remote_device_db) break;
551             bt_flip_addr(addr, &packet[2]);
552             hci_stack.remote_device_db->put_link_key(&addr, (link_key_t *) &packet[8]);
553             // still forward event to allow dismiss of pairing dialog
554             break;
555 
556         case HCI_EVENT_PIN_CODE_REQUEST:
557             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_PIN_CODE_REQUEST);
558             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
559             if (!hci_stack.remote_device_db) break;
560             bt_flip_addr(addr, &packet[2]);
561             hci_stack.remote_device_db->delete_link_key(&addr);
562             break;
563 
564         case HCI_EVENT_IO_CAPABILITY_REQUEST:
565             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
566             if (hci_stack.ssp_io_capability == SSP_IO_CAPABILITY_UNKNOWN) break;
567             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SENT_IO_CAPABILITIES_REPLY);
568             break;
569 
570 #ifndef EMBEDDED
571         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
572             if (!hci_stack.remote_device_db) break;
573             if (packet[2]) break; // status not ok
574             bt_flip_addr(addr, &packet[3]);
575             // fix for invalid remote names - terminate on 0xff
576             for (i=0; i<248;i++){
577                 if (packet[9+i] == 0xff){
578                     packet[9+i] = 0;
579                     break;
580                 }
581             }
582             memset(&device_name, 0, sizeof(device_name_t));
583             strncpy((char*) device_name, (char*) &packet[9], 248);
584             hci_stack.remote_device_db->put_name(&addr, &device_name);
585             break;
586 
587         case HCI_EVENT_INQUIRY_RESULT:
588         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
589             if (!hci_stack.remote_device_db) break;
590             // first send inq result packet
591             hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
592             // then send cached remote names
593             for (i=0; i<packet[2];i++){
594                 bt_flip_addr(addr, &packet[3+i*6]);
595                 if (hci_stack.remote_device_db->get_name(&addr, &device_name)){
596                     hci_emit_remote_name_cached(&addr, &device_name);
597                 }
598             }
599             return;
600 #endif
601 
602         case HCI_EVENT_DISCONNECTION_COMPLETE:
603             if (!packet[2]){
604                 handle = READ_BT_16(packet, 3);
605                 hci_connection_t * conn = connection_for_handle(handle);
606                 if (conn) {
607                     hci_shutdown_connection(conn);
608                 }
609             }
610             break;
611 
612         case HCI_EVENT_HARDWARE_ERROR:
613             if(hci_stack.control->hw_error){
614                 (*hci_stack.control->hw_error)();
615             }
616             break;
617 
618 #ifdef HAVE_BLE
619         case HCI_EVENT_LE_META:
620             switch (packet[2]) {
621                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
622                     // Connection management
623                     bt_flip_addr(addr, &packet[8]);
624                     log_info("LE Connection_complete (status=%u) %s\n", packet[3], bd_addr_to_str(addr));
625                     // LE connections are auto-accepted, so just create a connection if there isn't one already
626                     conn = connection_for_address(addr);
627                     if (packet[3]){
628                         if (conn){
629                             // outgoing connection failed, remove entry
630                             linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
631                             btstack_memory_hci_connection_free( conn );
632 
633                         }
634                         // if authentication error, also delete link key
635                         if (packet[3] == 0x05) {
636                             hci_drop_link_key_for_bd_addr(&addr);
637                         }
638                         break;
639                     }
640                     if (!conn){
641                         conn = create_connection_for_addr(addr);
642                     }
643                     if (!conn){
644                         // no memory
645                         break;
646                     }
647 
648                     conn->state = OPEN;
649                     conn->con_handle = READ_BT_16(packet, 4);
650 
651                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
652 
653                     // restart timer
654                     // run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
655                     // run_loop_add_timer(&conn->timeout);
656 
657                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
658 
659                     hci_emit_nr_connections_changed();
660                     break;
661 
662                 default:
663                     break;
664             }
665             break;
666 #endif
667 
668         default:
669             break;
670     }
671 
672     // handle BT initialization
673     if (hci_stack.state == HCI_STATE_INITIALIZING){
674         // handle H4 synchronization loss on restart
675         // if (hci_stack.substate == 1 && packet[0] == HCI_EVENT_HARDWARE_ERROR){
676         //    hci_stack.substate = 0;
677         // }
678         // handle normal init sequence
679         if (hci_stack.substate % 2){
680             // odd: waiting for event
681             if (packet[0] == HCI_EVENT_COMMAND_COMPLETE || packet[0] == HCI_EVENT_COMMAND_STATUS){
682                 hci_stack.substate++;
683             }
684         }
685     }
686 
687     // help with BT sleep
688     if (hci_stack.state == HCI_STATE_FALLING_ASLEEP
689         && hci_stack.substate == 1
690         && COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
691         hci_stack.substate++;
692     }
693 
694     hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
695 
696 	// execute main loop
697 	hci_run();
698 }
699 
700 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
701     switch (packet_type) {
702         case HCI_EVENT_PACKET:
703             event_handler(packet, size);
704             break;
705         case HCI_ACL_DATA_PACKET:
706             acl_handler(packet, size);
707             break;
708         default:
709             break;
710     }
711 }
712 
713 /** Register HCI packet handlers */
714 void hci_register_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
715     hci_stack.packet_handler = handler;
716 }
717 
718 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control, remote_device_db_t const* remote_device_db){
719 
720     // reference to use transport layer implementation
721     hci_stack.hci_transport = transport;
722 
723     // references to used control implementation
724     hci_stack.control = control;
725 
726     // reference to used config
727     hci_stack.config = config;
728 
729     // no connections yet
730     hci_stack.connections = NULL;
731     hci_stack.discoverable = 0;
732     hci_stack.connectable = 0;
733 
734     // no pending cmds
735     hci_stack.decline_reason = 0;
736     hci_stack.new_scan_enable_value = 0xff;
737 
738     // higher level handler
739     hci_stack.packet_handler = dummy_handler;
740 
741     // store and open remote device db
742     hci_stack.remote_device_db = remote_device_db;
743     if (hci_stack.remote_device_db) {
744         hci_stack.remote_device_db->open();
745     }
746 
747     // max acl payload size defined in config.h
748     hci_stack.acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
749 
750     // register packet handlers with transport
751     transport->register_packet_handler(&packet_handler);
752 
753     hci_stack.state = HCI_STATE_OFF;
754 
755     // class of device
756     hci_stack.class_of_device = 0x007a020c; // Smartphone
757 
758     // Secure Simple Pairing
759     hci_stack.ssp_enable = 0;
760     hci_stack.ssp_io_capability = SSP_IO_CAPABILITY_UNKNOWN;
761     hci_stack.ssp_authentication_requirement = 0;
762 }
763 
764 void hci_close(){
765     // close remote device db
766     if (hci_stack.remote_device_db) {
767         hci_stack.remote_device_db->close();
768     }
769     while (hci_stack.connections) {
770         hci_shutdown_connection((hci_connection_t *) hci_stack.connections);
771 }
772     hci_power_control(HCI_POWER_OFF);
773 }
774 
775 // State-Module-Driver overview
776 // state                    module  low-level
777 // HCI_STATE_OFF             off      close
778 // HCI_STATE_INITIALIZING,   on       open
779 // HCI_STATE_WORKING,        on       open
780 // HCI_STATE_HALTING,        on       open
781 // HCI_STATE_SLEEPING,    off/sleep   close
782 // HCI_STATE_FALLING_ASLEEP  on       open
783 
784 static int hci_power_control_on(void){
785 
786     // power on
787     int err = 0;
788     if (hci_stack.control && hci_stack.control->on){
789         err = (*hci_stack.control->on)(hci_stack.config);
790     }
791     if (err){
792         log_error( "POWER_ON failed\n");
793         hci_emit_hci_open_failed();
794         return err;
795     }
796 
797     // open low-level device
798     err = hci_stack.hci_transport->open(hci_stack.config);
799     if (err){
800         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
801         if (hci_stack.control && hci_stack.control->off){
802             (*hci_stack.control->off)(hci_stack.config);
803         }
804         hci_emit_hci_open_failed();
805         return err;
806     }
807     return 0;
808 }
809 
810 static void hci_power_control_off(void){
811 
812     log_info("hci_power_control_off\n");
813 
814     // close low-level device
815     hci_stack.hci_transport->close(hci_stack.config);
816 
817     log_info("hci_power_control_off - hci_transport closed\n");
818 
819     // power off
820     if (hci_stack.control && hci_stack.control->off){
821         (*hci_stack.control->off)(hci_stack.config);
822     }
823 
824     log_info("hci_power_control_off - control closed\n");
825 
826     hci_stack.state = HCI_STATE_OFF;
827 }
828 
829 static void hci_power_control_sleep(void){
830 
831     log_info("hci_power_control_sleep\n");
832 
833 #if 0
834     // don't close serial port during sleep
835 
836     // close low-level device
837     hci_stack.hci_transport->close(hci_stack.config);
838 #endif
839 
840     // sleep mode
841     if (hci_stack.control && hci_stack.control->sleep){
842         (*hci_stack.control->sleep)(hci_stack.config);
843     }
844 
845     hci_stack.state = HCI_STATE_SLEEPING;
846 }
847 
848 static int hci_power_control_wake(void){
849 
850     log_info("hci_power_control_wake\n");
851 
852     // wake on
853     if (hci_stack.control && hci_stack.control->wake){
854         (*hci_stack.control->wake)(hci_stack.config);
855     }
856 
857 #if 0
858     // open low-level device
859     int err = hci_stack.hci_transport->open(hci_stack.config);
860     if (err){
861         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
862         if (hci_stack.control && hci_stack.control->off){
863             (*hci_stack.control->off)(hci_stack.config);
864         }
865         hci_emit_hci_open_failed();
866         return err;
867     }
868 #endif
869 
870     return 0;
871 }
872 
873 
874 int hci_power_control(HCI_POWER_MODE power_mode){
875 
876     log_info("hci_power_control: %u, current mode %u\n", power_mode, hci_stack.state);
877 
878     int err = 0;
879     switch (hci_stack.state){
880 
881         case HCI_STATE_OFF:
882             switch (power_mode){
883                 case HCI_POWER_ON:
884                     err = hci_power_control_on();
885                     if (err) return err;
886                     // set up state machine
887                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
888                     hci_stack.state = HCI_STATE_INITIALIZING;
889                     hci_stack.substate = 0;
890                     break;
891                 case HCI_POWER_OFF:
892                     // do nothing
893                     break;
894                 case HCI_POWER_SLEEP:
895                     // do nothing (with SLEEP == OFF)
896                     break;
897             }
898             break;
899 
900         case HCI_STATE_INITIALIZING:
901             switch (power_mode){
902                 case HCI_POWER_ON:
903                     // do nothing
904                     break;
905                 case HCI_POWER_OFF:
906                     // no connections yet, just turn it off
907                     hci_power_control_off();
908                     break;
909                 case HCI_POWER_SLEEP:
910                     // no connections yet, just turn it off
911                     hci_power_control_sleep();
912                     break;
913             }
914             break;
915 
916         case HCI_STATE_WORKING:
917             switch (power_mode){
918                 case HCI_POWER_ON:
919                     // do nothing
920                     break;
921                 case HCI_POWER_OFF:
922                     // see hci_run
923                     hci_stack.state = HCI_STATE_HALTING;
924                     break;
925                 case HCI_POWER_SLEEP:
926                     // see hci_run
927                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
928                     hci_stack.substate = 0;
929                     break;
930             }
931             break;
932 
933         case HCI_STATE_HALTING:
934             switch (power_mode){
935                 case HCI_POWER_ON:
936                     // set up state machine
937                     hci_stack.state = HCI_STATE_INITIALIZING;
938                     hci_stack.substate = 0;
939                     break;
940                 case HCI_POWER_OFF:
941                     // do nothing
942                     break;
943                 case HCI_POWER_SLEEP:
944                     // see hci_run
945                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
946                     hci_stack.substate = 0;
947                     break;
948             }
949             break;
950 
951         case HCI_STATE_FALLING_ASLEEP:
952             switch (power_mode){
953                 case HCI_POWER_ON:
954 
955 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
956                     // nothing to do, if H4 supports power management
957                     if (bt_control_iphone_power_management_enabled()){
958                         hci_stack.state = HCI_STATE_INITIALIZING;
959                         hci_stack.substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
960                         break;
961                     }
962 #endif
963                     // set up state machine
964                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
965                     hci_stack.state = HCI_STATE_INITIALIZING;
966                     hci_stack.substate = 0;
967                     break;
968                 case HCI_POWER_OFF:
969                     // see hci_run
970                     hci_stack.state = HCI_STATE_HALTING;
971                     break;
972                 case HCI_POWER_SLEEP:
973                     // do nothing
974                     break;
975             }
976             break;
977 
978         case HCI_STATE_SLEEPING:
979             switch (power_mode){
980                 case HCI_POWER_ON:
981 
982 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
983                     // nothing to do, if H4 supports power management
984                     if (bt_control_iphone_power_management_enabled()){
985                         hci_stack.state = HCI_STATE_INITIALIZING;
986                         hci_stack.substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
987                         hci_update_scan_enable();
988                         break;
989                     }
990 #endif
991                     err = hci_power_control_wake();
992                     if (err) return err;
993                     // set up state machine
994                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
995                     hci_stack.state = HCI_STATE_INITIALIZING;
996                     hci_stack.substate = 0;
997                     break;
998                 case HCI_POWER_OFF:
999                     hci_stack.state = HCI_STATE_HALTING;
1000                     break;
1001                 case HCI_POWER_SLEEP:
1002                     // do nothing
1003                     break;
1004             }
1005             break;
1006     }
1007 
1008     // create internal event
1009 	hci_emit_state();
1010 
1011 	// trigger next/first action
1012 	hci_run();
1013 
1014     return 0;
1015 }
1016 
1017 static void hci_update_scan_enable(void){
1018     // 2 = page scan, 1 = inq scan
1019     hci_stack.new_scan_enable_value  = hci_stack.connectable << 1 | hci_stack.discoverable;
1020     hci_run();
1021 }
1022 
1023 void hci_discoverable_control(uint8_t enable){
1024     if (enable) enable = 1; // normalize argument
1025 
1026     if (hci_stack.discoverable == enable){
1027         hci_emit_discoverable_enabled(hci_stack.discoverable);
1028         return;
1029     }
1030 
1031     hci_stack.discoverable = enable;
1032     hci_update_scan_enable();
1033 }
1034 
1035 void hci_connectable_control(uint8_t enable){
1036     if (enable) enable = 1; // normalize argument
1037 
1038     // don't emit event
1039     if (hci_stack.connectable == enable) return;
1040 
1041     hci_stack.connectable = enable;
1042     hci_update_scan_enable();
1043 }
1044 
1045 void hci_run(){
1046 
1047     hci_connection_t * connection;
1048     linked_item_t * it;
1049 
1050     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1051 
1052     // global/non-connection oriented commands
1053 
1054     // decline incoming connections
1055     if (hci_stack.decline_reason){
1056         uint8_t reason = hci_stack.decline_reason;
1057         hci_stack.decline_reason = 0;
1058         hci_send_cmd(&hci_reject_connection_request, hci_stack.decline_addr, reason);
1059     }
1060 
1061     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1062 
1063     // send scan enable
1064     if (hci_stack.state == HCI_STATE_WORKING && hci_stack.new_scan_enable_value != 0xff){
1065         hci_send_cmd(&hci_write_scan_enable, hci_stack.new_scan_enable_value);
1066         hci_stack.new_scan_enable_value = 0xff;
1067     }
1068 
1069     // send pending HCI commands
1070     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
1071 
1072         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1073 
1074         connection = (hci_connection_t *) it;
1075 
1076         if (connection->state == RECEIVED_CONNECTION_REQUEST){
1077             log_info("sending hci_accept_connection_request\n");
1078             hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
1079             connection->state = ACCEPTED_CONNECTION_REQUEST;
1080         }
1081 
1082         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1083 
1084         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
1085             link_key_t link_key;
1086             log_info("responding to link key request\n");
1087             if ( hci_stack.remote_device_db->get_link_key( &connection->address, &link_key)){
1088                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
1089             } else {
1090                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
1091             }
1092             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
1093         }
1094 
1095         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1096 
1097         if (connection->authentication_flags & SENT_IO_CAPABILITIES_REPLY){
1098             hci_send_cmd(&hci_io_capability_request_reply, hci_stack.ssp_io_capability, NULL, hci_stack.ssp_authentication_requirement);
1099             connectionClearAuthenticationFlags(connection, SENT_IO_CAPABILITIES_REPLY);
1100         }
1101     }
1102 
1103     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1104 
1105     switch (hci_stack.state){
1106         case HCI_STATE_INITIALIZING:
1107             // log_info("hci_init: substate %u\n", hci_stack.substate);
1108             if (hci_stack.substate % 2) {
1109                 // odd: waiting for command completion
1110                 return;
1111             }
1112             switch (hci_stack.substate >> 1){
1113                 case 0: // RESET
1114                     hci_send_cmd(&hci_reset);
1115                     if (hci_stack.config == 0 || ((hci_uart_config_t *)hci_stack.config)->baudrate_main == 0){
1116                         // skip baud change
1117                         hci_stack.substate = 4; // >> 1 = 2
1118                     }
1119                     break;
1120                 case 1: // SEND BAUD CHANGE
1121                     hci_stack.control->baudrate_cmd(hci_stack.config, ((hci_uart_config_t *)hci_stack.config)->baudrate_main, hci_stack.hci_packet_buffer);
1122                     hci_send_cmd_packet(hci_stack.hci_packet_buffer, 3 + hci_stack.hci_packet_buffer[2]);
1123                     break;
1124                 case 2: // LOCAL BAUD CHANGE
1125                     hci_stack.hci_transport->set_baudrate(((hci_uart_config_t *)hci_stack.config)->baudrate_main);
1126                     hci_stack.substate += 2;
1127                     // break missing here for fall through
1128 
1129                 case 3:
1130                     // custom initialization
1131                     if (hci_stack.control && hci_stack.control->next_cmd){
1132                         int valid_cmd = (*hci_stack.control->next_cmd)(hci_stack.config, hci_stack.hci_packet_buffer);
1133                         if (valid_cmd){
1134                             int size = 3 + hci_stack.hci_packet_buffer[2];
1135                             hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack.hci_packet_buffer, size);
1136                             hci_stack.substate = 4; // more init commands
1137                             break;
1138                         }
1139                         log_info("hci_run: init script done\n\r");
1140                     }
1141                     // otherwise continue
1142 					hci_send_cmd(&hci_read_bd_addr);
1143 					break;
1144 				case 4:
1145 					hci_send_cmd(&hci_read_buffer_size);
1146 					break;
1147                 case 5:
1148                     // ca. 15 sec
1149                     hci_send_cmd(&hci_write_page_timeout, 0x6000);
1150                     break;
1151                 case 6:
1152                     hci_send_cmd(&hci_read_local_supported_features);
1153                     break;
1154                 case 7:
1155                     hci_send_cmd(&hci_write_class_of_device, hci_stack.class_of_device);
1156                     break;
1157                 case 8:
1158                     if (hci_stack.local_name){
1159                         hci_send_cmd(&hci_write_local_name, hci_stack.local_name);
1160                     } else {
1161                         char hostname[30];
1162 #ifdef EMBEDDED
1163                         // BTstack-11:22:33:44:55:66
1164                         strcpy(hostname, "BTstack ");
1165                         strcat(hostname, bd_addr_to_str(hci_stack.local_bd_addr));
1166                         printf("---> Name %s\n", hostname);
1167 #else
1168                         // hostname for POSIX systems
1169                         gethostname(hostname, 30);
1170                         hostname[29] = '\0';
1171 #endif
1172                         hci_send_cmd(&hci_write_local_name, hostname);
1173                     }
1174                     break;
1175                 case 9:
1176                     hci_send_cmd(&hci_set_event_mask,0xffffffff, 0xFFFFFFFF); ///0x1DFFFFFF
1177                     break;
1178                 case 10:
1179                     hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack.ssp_enable);
1180                     break;
1181                 case 11:
1182 					hci_send_cmd(&hci_write_scan_enable, (hci_stack.connectable << 1) | hci_stack.discoverable); // page scan
1183 					break;
1184                 case 12:
1185                     // done.
1186                     hci_stack.state = HCI_STATE_WORKING;
1187                     hci_emit_state();
1188                     break;
1189                 default:
1190                     break;
1191             }
1192             hci_stack.substate++;
1193             break;
1194 
1195         case HCI_STATE_HALTING:
1196 
1197             log_info("HCI_STATE_HALTING\n");
1198             // close all open connections
1199             connection =  (hci_connection_t *) hci_stack.connections;
1200             if (connection){
1201 
1202                 // send disconnect
1203                 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1204 
1205                 log_info("HCI_STATE_HALTING, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1206                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1207 
1208                 // send disconnected event right away - causes higher layer connections to get closed, too.
1209                 hci_shutdown_connection(connection);
1210                 return;
1211             }
1212             log_info("HCI_STATE_HALTING, calling off\n");
1213 
1214             // switch mode
1215             hci_power_control_off();
1216 
1217             log_info("HCI_STATE_HALTING, emitting state\n");
1218             hci_emit_state();
1219             log_info("HCI_STATE_HALTING, done\n");
1220             break;
1221 
1222         case HCI_STATE_FALLING_ASLEEP:
1223             switch(hci_stack.substate) {
1224                 case 0:
1225                     log_info("HCI_STATE_FALLING_ASLEEP\n");
1226                     // close all open connections
1227                     connection =  (hci_connection_t *) hci_stack.connections;
1228 
1229 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1230                     // don't close connections, if H4 supports power management
1231                     if (bt_control_iphone_power_management_enabled()){
1232                         connection = NULL;
1233                     }
1234 #endif
1235                     if (connection){
1236 
1237                         // send disconnect
1238                         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1239 
1240                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1241                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1242 
1243                         // send disconnected event right away - causes higher layer connections to get closed, too.
1244                         hci_shutdown_connection(connection);
1245                         return;
1246                     }
1247 
1248                     // disable page and inquiry scan
1249                     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1250 
1251                     log_info("HCI_STATE_HALTING, disabling inq cans\n");
1252                     hci_send_cmd(&hci_write_scan_enable, hci_stack.connectable << 1); // drop inquiry scan but keep page scan
1253 
1254                     // continue in next sub state
1255                     hci_stack.substate++;
1256                     break;
1257                 case 1:
1258                     // wait for command complete "hci_write_scan_enable" in event_handler();
1259                     break;
1260                 case 2:
1261                     log_info("HCI_STATE_HALTING, calling sleep\n");
1262 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1263                     // don't actually go to sleep, if H4 supports power management
1264                     if (bt_control_iphone_power_management_enabled()){
1265                         // SLEEP MODE reached
1266                         hci_stack.state = HCI_STATE_SLEEPING;
1267                         hci_emit_state();
1268                         break;
1269                     }
1270 #endif
1271                     // switch mode
1272                     hci_power_control_sleep();  // changes hci_stack.state to SLEEP
1273                     hci_emit_state();
1274                     break;
1275 
1276                 default:
1277                     break;
1278             }
1279             break;
1280 
1281         default:
1282             break;
1283     }
1284 }
1285 
1286 int hci_send_cmd_packet(uint8_t *packet, int size){
1287     bd_addr_t addr;
1288     hci_connection_t * conn;
1289     // house-keeping
1290 
1291     // create_connection?
1292     if (IS_COMMAND(packet, hci_create_connection)){
1293         bt_flip_addr(addr, &packet[3]);
1294         log_info("Create_connection to %s\n", bd_addr_to_str(addr));
1295         conn = connection_for_address(addr);
1296         if (conn) {
1297             // if connection exists
1298             if (conn->state == OPEN) {
1299                 // and OPEN, emit connection complete command
1300                 hci_emit_connection_complete(conn, 0);
1301             }
1302             //    otherwise, just ignore as it is already in the open process
1303             return 0; // don't sent packet to controller
1304 
1305         }
1306         // create connection struct and register, state = SENT_CREATE_CONNECTION
1307         conn = create_connection_for_addr(addr);
1308         if (!conn){
1309             // notify client that alloc failed
1310             hci_emit_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
1311             return 0; // don't sent packet to controller
1312         }
1313         conn->state = SENT_CREATE_CONNECTION;
1314     }
1315 
1316     if (IS_COMMAND(packet, hci_link_key_request_reply)){
1317         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
1318     }
1319     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
1320         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
1321     }
1322     if (IS_COMMAND(packet, hci_pin_code_request_reply)){
1323         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_REPLY);
1324     }
1325     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)){
1326         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_NEGATIVE_REPLY);
1327     }
1328 
1329     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
1330         if (hci_stack.remote_device_db){
1331             bt_flip_addr(addr, &packet[3]);
1332             hci_stack.remote_device_db->delete_link_key(&addr);
1333         }
1334     }
1335 
1336     hci_stack.num_cmd_packets--;
1337     return hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
1338 }
1339 
1340 /**
1341  * pre: numcmds >= 0 - it's allowed to send a command to the controller
1342  */
1343 int hci_send_cmd(const hci_cmd_t *cmd, ...){
1344     va_list argptr;
1345     va_start(argptr, cmd);
1346     uint16_t size = hci_create_cmd_internal(hci_stack.hci_packet_buffer, cmd, argptr);
1347     va_end(argptr);
1348     return hci_send_cmd_packet(hci_stack.hci_packet_buffer, size);
1349 }
1350 
1351 // Create various non-HCI events.
1352 // TODO: generalize, use table similar to hci_create_command
1353 
1354 void hci_emit_state(){
1355     log_info("BTSTACK_EVENT_STATE %u", hci_stack.state);
1356     uint8_t event[3];
1357     event[0] = BTSTACK_EVENT_STATE;
1358     event[1] = sizeof(event) - 2;
1359     event[2] = hci_stack.state;
1360     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1361     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1362 }
1363 
1364 void hci_emit_connection_complete(hci_connection_t *conn, uint8_t status){
1365     uint8_t event[13];
1366     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
1367     event[1] = sizeof(event) - 2;
1368     event[2] = status;
1369     bt_store_16(event, 3, conn->con_handle);
1370     bt_flip_addr(&event[5], conn->address);
1371     event[11] = 1; // ACL connection
1372     event[12] = 0; // encryption disabled
1373     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1374     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1375 }
1376 
1377 void hci_emit_disconnection_complete(uint16_t handle, uint8_t reason){
1378     uint8_t event[6];
1379     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
1380     event[1] = sizeof(event) - 2;
1381     event[2] = 0; // status = OK
1382     bt_store_16(event, 3, handle);
1383     event[5] = reason;
1384     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1385     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1386 }
1387 
1388 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
1389     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
1390     uint8_t event[4];
1391     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
1392     event[1] = sizeof(event) - 2;
1393     bt_store_16(event, 2, conn->con_handle);
1394     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1395     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1396 }
1397 
1398 void hci_emit_nr_connections_changed(){
1399     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
1400     uint8_t event[3];
1401     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
1402     event[1] = sizeof(event) - 2;
1403     event[2] = nr_hci_connections();
1404     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1405     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1406 }
1407 
1408 void hci_emit_hci_open_failed(){
1409     log_info("BTSTACK_EVENT_POWERON_FAILED");
1410     uint8_t event[2];
1411     event[0] = BTSTACK_EVENT_POWERON_FAILED;
1412     event[1] = sizeof(event) - 2;
1413     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1414     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1415 }
1416 
1417 #ifndef EMBEDDED
1418 void hci_emit_btstack_version() {
1419     log_info("BTSTACK_EVENT_VERSION %u.%u", BTSTACK_MAJOR, BTSTACK_MINOR);
1420     uint8_t event[6];
1421     event[0] = BTSTACK_EVENT_VERSION;
1422     event[1] = sizeof(event) - 2;
1423     event[2] = BTSTACK_MAJOR;
1424     event[3] = BTSTACK_MINOR;
1425     bt_store_16(event, 4, BTSTACK_REVISION);
1426     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1427     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1428 }
1429 #endif
1430 
1431 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
1432     log_info("BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED %u", enabled);
1433     uint8_t event[3];
1434     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
1435     event[1] = sizeof(event) - 2;
1436     event[2] = enabled;
1437     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1438     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1439 }
1440 
1441 void hci_emit_remote_name_cached(bd_addr_t *addr, device_name_t *name){
1442     uint8_t event[2+1+6+248+1]; // +1 for \0 in log_info
1443     event[0] = BTSTACK_EVENT_REMOTE_NAME_CACHED;
1444     event[1] = sizeof(event) - 2 - 1;
1445     event[2] = 0;   // just to be compatible with HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
1446     bt_flip_addr(&event[3], *addr);
1447     memcpy(&event[9], name, 248);
1448 
1449     event[9+248] = 0;   // assert \0 for log_info
1450     log_info("BTSTACK_EVENT_REMOTE_NAME_CACHED %s = '%s'", bd_addr_to_str(*addr), &event[9]);
1451 
1452     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)-1);
1453     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event)-1);
1454 }
1455 
1456 void hci_emit_discoverable_enabled(uint8_t enabled){
1457     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
1458     uint8_t event[3];
1459     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
1460     event[1] = sizeof(event) - 2;
1461     event[2] = enabled;
1462     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1463     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1464 }
1465