xref: /btstack/example/gatt_battery_query.c (revision 0561b2d8d5dba972c7daa57d5e677f7a1327edfd)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "gatt_battery_query.c"
39 
40 // *****************************************************************************
41 //
42 // BLE Client
43 //
44 // *****************************************************************************
45 
46 #include <stdint.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 
51 #include "btstack.h"
52 
53 // gatt_battery_query.gatt contains the declaration of the provided GATT Services + Characteristics
54 // gatt_battery_query.h    contains the binary representation of gatt_battery_query.gatt
55 // it is generated by the build system by calling: $BTSTACK_ROOT/tool/compile_gatt.py gatt_battery_query.gatt gatt_battery_query.h
56 // it needs to be regenerated when the GATT Database declared in gatt_battery_query.gatt file is modified
57 #include "gatt_battery_query.h"
58 
59 typedef struct advertising_report {
60     uint8_t   type;
61     uint8_t   event_type;
62     uint8_t   address_type;
63     bd_addr_t address;
64     uint8_t   rssi;
65     uint8_t   length;
66     const uint8_t * data;
67 } advertising_report_t;
68 
69 
70 typedef enum {
71     TC_IDLE,
72     TC_W4_SCAN_RESULT,
73     TC_W4_CONNECT,
74     TC_W4_SERVICE_RESULT,
75     TC_W4_CHARACTERISTIC_RESULT,
76     TC_W4_BATTERY_DATA
77 } gc_state_t;
78 
79 static int blacklist_index = 0;
80 static bd_addr_t blacklist[20];
81 static advertising_report_t report;
82 
83 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
84 
85 static bd_addr_t cmdline_addr;
86 static int cmdline_addr_found = 0;
87 
88 static hci_con_handle_t connection_handle;
89 static uint16_t battery_service_uuid = 0x180F;
90 static uint16_t battery_level_characteristic_uuid = 0x2a19;
91 static gatt_client_service_t battery_service;
92 static gatt_client_characteristic_t battery_level_characteristic;
93 
94 static gc_state_t state = TC_IDLE;
95 static btstack_packet_callback_registration_t hci_event_callback_registration;
96 
97 static gatt_client_notification_t notification_listener;
98 static int listener_registered;
99 
100 static void printUUID(uint8_t * uuid128, uint16_t uuid16){
101     if (uuid16){
102         printf("%04x",uuid16);
103     } else {
104         printf("%s", uuid128_to_str(uuid128));
105     }
106 }
107 
108 static int blacklist_size(void){
109     return sizeof(blacklist) / sizeof(bd_addr_t);
110 }
111 
112 static int blacklist_contains(bd_addr_t addr){
113     int i;
114     for (i=0; i<blacklist_size(); i++){
115         if (bd_addr_cmp(addr, blacklist[i]) == 0) return 1;
116     }
117     return 0;
118 }
119 
120 static void add_to_blacklist(bd_addr_t addr){
121     printf("%s added to blacklist (no battery service found\n", bd_addr_to_str(addr));
122     bd_addr_copy(blacklist[blacklist_index], addr);
123     blacklist_index = (blacklist_index + 1) % blacklist_size();
124 }
125 
126 static void dump_advertising_report(advertising_report_t * e){
127     printf("    * adv. event: evt-type %u, addr-type %u, addr %s, rssi %u, length adv %u, data: ", e->event_type,
128            e->address_type, bd_addr_to_str(e->address), e->rssi, e->length);
129     printf_hexdump(e->data, e->length);
130 
131 }
132 
133 static void dump_characteristic_value(uint8_t * blob, uint16_t blob_length){
134     printf("    * characteristic value of length %d *** ", blob_length );
135     printf_hexdump(blob , blob_length);
136     printf("\n");
137 }
138 
139 static void dump_characteristic(gatt_client_characteristic_t * characteristic){
140     printf("    * characteristic: [0x%04x-0x%04x-0x%04x], properties 0x%02x, uuid ",
141                             characteristic->start_handle, characteristic->value_handle, characteristic->end_handle, characteristic->properties);
142     printUUID(characteristic->uuid128, characteristic->uuid16);
143     printf("\n");
144 }
145 
146 static void dump_service(gatt_client_service_t * service){
147     printf("    * service: [0x%04x-0x%04x], uuid ", service->start_group_handle, service->end_group_handle);
148     printUUID(service->uuid128, service->uuid16);
149     printf("\n");
150 }
151 
152 
153 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
154     UNUSED(packet_type);
155     UNUSED(channel);
156     UNUSED(size);
157 
158     int status;
159     uint8_t battery_level;
160 
161     switch(state){
162         case TC_W4_SERVICE_RESULT:
163             switch(hci_event_packet_get_type(packet)){
164                 case GATT_EVENT_SERVICE_QUERY_RESULT:
165                     gatt_event_service_query_result_get_service(packet, &battery_service);
166                     dump_service(&battery_service);
167                     break;
168                 case GATT_EVENT_QUERY_COMPLETE:
169                     if (packet[4] != 0){
170                         printf("SERVICE_QUERY_RESULT - Error status %x.\n", packet[4]);
171                         add_to_blacklist(report.address);
172                         gap_disconnect(connection_handle);
173                         break;
174                     }
175                     state = TC_W4_CHARACTERISTIC_RESULT;
176                     printf("\nSearch for battery level characteristic.\n");
177                     gatt_client_discover_characteristics_for_service_by_uuid16(handle_gatt_client_event, connection_handle, &battery_service, battery_level_characteristic_uuid);
178                     break;
179                 default:
180                     break;
181             }
182             break;
183 
184         case TC_W4_CHARACTERISTIC_RESULT:
185             switch(hci_event_packet_get_type(packet)){
186                 case GATT_EVENT_CHARACTERISTIC_QUERY_RESULT:
187                     gatt_event_characteristic_query_result_get_characteristic(packet, &battery_level_characteristic);
188                     dump_characteristic(&battery_level_characteristic);
189                     break;
190                 case GATT_EVENT_QUERY_COMPLETE:
191                     if (packet[4] != 0){
192                         printf("CHARACTERISTIC_QUERY_RESULT - Error status %x.\n", packet[4]);
193                         add_to_blacklist(report.address);
194                         gap_disconnect(connection_handle);
195                         break;
196                     }
197 
198                     // register handler for notifications
199                     listener_registered = 1;
200                     gatt_client_listen_for_characteristic_value_updates(&notification_listener, handle_gatt_client_event, connection_handle, &battery_level_characteristic);
201 
202                     state = TC_W4_BATTERY_DATA;
203                     printf("\nConfigure battery level characteristic for notify.\n");
204                     status = gatt_client_write_client_characteristic_configuration(handle_gatt_client_event, connection_handle, &battery_level_characteristic, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION);
205                     if (status != 0){
206                         printf("\nNotification not supported. Query value of characteristic.\n");
207                         gatt_client_read_value_of_characteristic(handle_gatt_client_event, connection_handle, &battery_level_characteristic);
208                     }
209 
210                     break;
211                 default:
212                     break;
213             }
214             break;
215         case TC_W4_BATTERY_DATA:
216             switch(hci_event_packet_get_type(packet)){
217                 case GATT_EVENT_NOTIFICATION:
218                     printf("\nBattery Data:\n");
219                     dump_characteristic_value(&packet[8], little_endian_read_16(packet, 6));
220                     break;
221                 case GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT:
222 
223                         if (gatt_event_characteristic_value_query_result_get_value_length(packet) < 1) break;
224                         battery_level = gatt_event_characteristic_value_query_result_get_value(packet)[0];
225                         printf("Battery level %d \n", battery_level);
226                     break;
227 
228                 case GATT_EVENT_QUERY_COMPLETE:
229                     if (packet[4] != 0){
230                         printf("CHARACTERISTIC_VALUE_QUERY_RESULT - Error status %x.\n", packet[4]);
231                         break;
232                     }
233                     break;
234                 default:
235                     printf("Unknown packet type %x\n", hci_event_packet_get_type(packet));
236                     break;
237             }
238             break;
239 
240         default:
241             printf("error\n");
242             break;
243     }
244 
245 }
246 
247 static void fill_advertising_report_from_packet(advertising_report_t * adv_report, uint8_t *packet){
248     gap_event_advertising_report_get_address(packet, adv_report->address);
249     adv_report->event_type = gap_event_advertising_report_get_advertising_event_type(packet);
250     adv_report->address_type = gap_event_advertising_report_get_address_type(packet);
251     adv_report->rssi = gap_event_advertising_report_get_rssi(packet);
252     adv_report->length = gap_event_advertising_report_get_data_length(packet);
253     adv_report->data = gap_event_advertising_report_get_data(packet);
254 }
255 
256 static void hci_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
257     UNUSED(channel);
258     UNUSED(size);
259 
260     if (packet_type != HCI_EVENT_PACKET) return;
261 
262     uint8_t event = hci_event_packet_get_type(packet);
263     switch (event) {
264         case BTSTACK_EVENT_STATE:
265             // BTstack activated, get started
266             if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) break;
267             if (cmdline_addr_found){
268                 printf("Connect to %s\n", bd_addr_to_str(cmdline_addr));
269                 state = TC_W4_CONNECT;
270                 gap_connect(cmdline_addr, 0);
271                 break;
272             }
273             printf("Start scanning!\n");
274             state = TC_W4_SCAN_RESULT;
275             gap_set_scan_parameters(0,0x0030, 0x0030);
276             gap_start_scan();
277             break;
278         case GAP_EVENT_ADVERTISING_REPORT:
279             if (state != TC_W4_SCAN_RESULT) return;
280             fill_advertising_report_from_packet(&report, packet);
281 
282             if (blacklist_contains(report.address)) {
283                 break;
284             }
285             dump_advertising_report(&report);
286             // stop scanning, and connect to the device
287             state = TC_W4_CONNECT;
288             gap_stop_scan();
289             printf("Stop scan. Connect to device with addr %s.\n", bd_addr_to_str(report.address));
290             gap_connect(report.address,report.address_type);
291 
292             break;
293         case HCI_EVENT_LE_META:
294             // wait for connection complete
295             if (hci_event_le_meta_get_subevent_code(packet) !=  HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break;
296             if (state != TC_W4_CONNECT) return;
297             connection_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
298             // initialize gatt client context with handle, and add it to the list of active clients
299             // query primary services
300             printf("\nSearch for battery service.\n");
301             state = TC_W4_SERVICE_RESULT;
302             gatt_client_discover_primary_services_by_uuid16(handle_gatt_client_event, connection_handle, battery_service_uuid);
303             break;
304         case HCI_EVENT_DISCONNECTION_COMPLETE:
305             // unregister listener
306             connection_handle = HCI_CON_HANDLE_INVALID;
307             if (listener_registered){
308                 listener_registered = 0;
309                 gatt_client_stop_listening_for_characteristic_value_updates(&notification_listener);
310             }
311 
312             if (cmdline_addr_found){
313                 printf("\nDisconnected %s\n", bd_addr_to_str(cmdline_addr));
314                 return;
315             }
316 
317             printf("\nDisconnected %s\n", bd_addr_to_str(report.address));
318             printf("Restart scan.\n");
319             state = TC_W4_SCAN_RESULT;
320             gap_start_scan();
321             break;
322         default:
323             break;
324     }
325 }
326 
327 #ifdef HAVE_BTSTACK_STDIN
328 static void usage(const char *name){
329     fprintf(stderr, "\nUsage: %s [-a|--address aa:bb:cc:dd:ee:ff]\n", name);
330     fprintf(stderr, "If no argument is provided, GATT browser will start scanning and connect to the first found device.\nTo connect to a specific device use argument [-a].\n\n");
331 }
332 #endif
333 
334 int btstack_main(int argc, const char * argv[]);
335 int btstack_main(int argc, const char * argv[]){
336 
337 #ifdef HAVE_BTSTACK_STDIN
338     int arg = 1;
339     cmdline_addr_found = 0;
340 
341     while (arg < argc) {
342         if(!strcmp(argv[arg], "-a") || !strcmp(argv[arg], "--address")){
343             arg++;
344             cmdline_addr_found = sscanf_bd_addr(argv[arg], cmdline_addr);
345             arg++;
346             if (!cmdline_addr_found) exit(1);
347             continue;
348         }
349         usage(argv[0]);
350         return 0;
351     }
352 #else
353     (void)argc;
354     (void)argv;
355 #endif
356     l2cap_init();
357 
358     // setup ATT server - only needed if LE Peripheral does ATT queries on its own, e.g. Android phones
359     att_server_init(profile_data, NULL, NULL);
360 
361     // GATT Client setup
362     gatt_client_init();
363 
364     sm_init();
365     sm_set_io_capabilities(IO_CAPABILITY_NO_INPUT_NO_OUTPUT);
366 
367     hci_event_callback_registration.callback = &hci_event_handler;
368     hci_add_event_handler(&hci_event_callback_registration);
369 
370 
371     // turn on!
372     hci_power_control(HCI_POWER_ON);
373 
374     return 0;
375 }
376 
377 
378 
379 
380