xref: /btstack/example/gatt_battery_query.c (revision f9f2075ceac5e9dc08e9abea437e43d733a3a0ea)
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 // *****************************************************************************
39 //
40 // BLE Client
41 //
42 // *****************************************************************************
43 
44 #include <stdint.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 
49 #include "btstack.h"
50 
51 typedef struct advertising_report {
52     uint8_t   type;
53     uint8_t   event_type;
54     uint8_t   address_type;
55     bd_addr_t address;
56     uint8_t   rssi;
57     uint8_t   length;
58     const uint8_t * data;
59 } advertising_report_t;
60 
61 
62 typedef enum {
63     TC_IDLE,
64     TC_W4_SCAN_RESULT,
65     TC_W4_CONNECT,
66     TC_W4_SERVICE_RESULT,
67     TC_W4_CHARACTERISTIC_RESULT,
68     TC_W4_BATTERY_DATA
69 } gc_state_t;
70 
71 static int blacklist_index = 0;
72 static bd_addr_t blacklist[20];
73 static advertising_report_t report;
74 
75 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
76 
77 static bd_addr_t cmdline_addr = { };
78 static int cmdline_addr_found = 0;
79 
80 static hci_con_handle_t connection_handle;
81 static uint16_t battery_service_uuid = 0x180F;
82 static uint16_t battery_level_characteristic_uuid = 0x2a19;
83 static gatt_client_service_t battery_service;
84 static gatt_client_characteristic_t config_characteristic;
85 
86 static gc_state_t state = TC_IDLE;
87 static btstack_packet_callback_registration_t hci_event_callback_registration;
88 
89 static void printUUID(uint8_t * uuid128, uint16_t uuid16){
90     if (uuid16){
91         printf("%04x",uuid16);
92     } else {
93         printf("%s", uuid128_to_str(uuid128));
94     }
95 }
96 
97 static int blacklist_size(void){
98     return sizeof(blacklist) / sizeof(bd_addr_t);
99 }
100 
101 static int blacklist_contains(bd_addr_t addr){
102     int i;
103     for (i=0; i<blacklist_size(); i++){
104         if (bd_addr_cmp(addr, blacklist[i]) == 0) return 1;
105     }
106     return 0;
107 }
108 
109 static void add_to_blacklist(bd_addr_t addr){
110     printf("%s added to blacklist (no battery service found\n", bd_addr_to_str(addr));
111     bd_addr_copy(blacklist[blacklist_index], addr);
112     blacklist_index = (blacklist_index + 1) % blacklist_size();
113 }
114 
115 static void dump_advertising_report(advertising_report_t * e){
116     printf("    * adv. event: evt-type %u, addr-type %u, addr %s, rssi %u, length adv %u, data: ", e->event_type,
117            e->address_type, bd_addr_to_str(e->address), e->rssi, e->length);
118     printf_hexdump(e->data, e->length);
119 
120 }
121 
122 static void dump_characteristic_value(uint8_t * blob, uint16_t blob_length){
123     printf("    * characteristic value of length %d *** ", blob_length );
124     printf_hexdump(blob , blob_length);
125     printf("\n");
126 }
127 
128 static void dump_characteristic(gatt_client_characteristic_t * characteristic){
129     printf("    * characteristic: [0x%04x-0x%04x-0x%04x], properties 0x%02x, uuid ",
130                             characteristic->start_handle, characteristic->value_handle, characteristic->end_handle, characteristic->properties);
131     printUUID(characteristic->uuid128, characteristic->uuid16);
132     printf("\n");
133 }
134 
135 static void dump_service(gatt_client_service_t * service){
136     printf("    * service: [0x%04x-0x%04x], uuid ", service->start_group_handle, service->end_group_handle);
137     printUUID(service->uuid128, service->uuid16);
138     printf("\n");
139 }
140 
141 
142 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
143     UNUSED(packet_type);
144     UNUSED(channel);
145     UNUSED(size);
146 
147     int status;
148     uint8_t battery_level;
149 
150     switch(state){
151         case TC_W4_SERVICE_RESULT:
152             switch(hci_event_packet_get_type(packet)){
153                 case GATT_EVENT_SERVICE_QUERY_RESULT:
154                     gatt_event_service_query_result_get_service(packet, &battery_service);
155                     dump_service(&battery_service);
156                     break;
157                 case GATT_EVENT_QUERY_COMPLETE:
158                     if (packet[4] != 0){
159                         printf("SERVICE_QUERY_RESULT - Error status %x.\n", packet[4]);
160                         add_to_blacklist(report.address);
161                         gap_disconnect(connection_handle);
162                         break;
163                     }
164                     state = TC_W4_CHARACTERISTIC_RESULT;
165                     printf("\nSearch for battery level characteristic.\n");
166                     gatt_client_discover_characteristics_for_service_by_uuid16(handle_gatt_client_event, connection_handle, &battery_service, battery_level_characteristic_uuid);
167                     break;
168                 default:
169                     break;
170             }
171             break;
172 
173         case TC_W4_CHARACTERISTIC_RESULT:
174             switch(hci_event_packet_get_type(packet)){
175                 case GATT_EVENT_CHARACTERISTIC_QUERY_RESULT:
176                     gatt_event_characteristic_query_result_get_characteristic(packet, &config_characteristic);
177                     dump_characteristic(&config_characteristic);
178                     break;
179                 case GATT_EVENT_QUERY_COMPLETE:
180                     if (packet[4] != 0){
181                         printf("CHARACTERISTIC_QUERY_RESULT - Error status %x.\n", packet[4]);
182                         add_to_blacklist(report.address);
183                         gap_disconnect(connection_handle);
184                         break;
185                     }
186                     state = TC_W4_BATTERY_DATA;
187                     printf("\nConfigure battery level characteristic for notify.\n");
188                     status = gatt_client_write_client_characteristic_configuration(handle_gatt_client_event, connection_handle, &config_characteristic, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION);
189                     if (status != 0){
190                         printf("\nNotification not supported. Query value of characteristic.\n");
191                         gatt_client_read_value_of_characteristic(handle_gatt_client_event, connection_handle, &config_characteristic);
192                     }
193 
194                     break;
195                 default:
196                     break;
197             }
198             break;
199         case TC_W4_BATTERY_DATA:
200             switch(hci_event_packet_get_type(packet)){
201                 case GATT_EVENT_NOTIFICATION:
202                     printf("\nBattery Data:\n");
203                     dump_characteristic_value(&packet[8], little_endian_read_16(packet, 6));
204                     break;
205                 case GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT:
206 
207                         if (gatt_event_characteristic_value_query_result_get_value_length(packet) < 1) break;
208                         battery_level = gatt_event_characteristic_value_query_result_get_value(packet)[0];
209                         printf("Battry level %d \n", battery_level);
210                     break;
211 
212                 case GATT_EVENT_QUERY_COMPLETE:
213                     if (packet[4] != 0){
214                         printf("CHARACTERISTIC_VALUE_QUERY_RESULT - Error status %x.\n", packet[4]);
215                         break;
216                     }
217                     // Use timer if repeated request is needed and notification is not supperted
218                     gap_disconnect(connection_handle);
219                     break;
220                 default:
221                     printf("Unknown packet type %x\n", hci_event_packet_get_type(packet));
222                     break;
223             }
224             break;
225 
226         default:
227             printf("error\n");
228             break;
229     }
230 
231 }
232 
233 static void fill_advertising_report_from_packet(advertising_report_t * adv_report, uint8_t *packet){
234     gap_event_advertising_report_get_address(packet, adv_report->address);
235     adv_report->event_type = gap_event_advertising_report_get_advertising_event_type(packet);
236     adv_report->address_type = gap_event_advertising_report_get_address_type(packet);
237     adv_report->rssi = gap_event_advertising_report_get_rssi(packet);
238     adv_report->length = gap_event_advertising_report_get_data_length(packet);
239     adv_report->data = gap_event_advertising_report_get_data(packet);
240 }
241 
242 static void hci_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
243     UNUSED(channel);
244     UNUSED(size);
245 
246     if (packet_type != HCI_EVENT_PACKET) return;
247 
248     uint8_t event = hci_event_packet_get_type(packet);
249     switch (event) {
250         case BTSTACK_EVENT_STATE:
251             // BTstack activated, get started
252             if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) break;
253             if (cmdline_addr_found){
254                 printf("Connect to %s\n", bd_addr_to_str(cmdline_addr));
255                 state = TC_W4_CONNECT;
256                 gap_connect(cmdline_addr, 0);
257                 break;
258             }
259             printf("Start scanning!\n");
260             state = TC_W4_SCAN_RESULT;
261             gap_set_scan_parameters(0,0x0030, 0x0030);
262             gap_start_scan();
263             break;
264         case GAP_EVENT_ADVERTISING_REPORT:
265             if (state != TC_W4_SCAN_RESULT) return;
266             fill_advertising_report_from_packet(&report, packet);
267 
268             if (blacklist_contains(report.address)) {
269                 break;
270             }
271             dump_advertising_report(&report);
272             // stop scanning, and connect to the device
273             state = TC_W4_CONNECT;
274             gap_stop_scan();
275             printf("Stop scan. Connect to device with addr %s.\n", bd_addr_to_str(report.address));
276             gap_connect(report.address,report.address_type);
277 
278             break;
279         case HCI_EVENT_LE_META:
280             // wait for connection complete
281             if (hci_event_le_meta_get_subevent_code(packet) !=  HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break;
282             if (state != TC_W4_CONNECT) return;
283             connection_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
284             // initialize gatt client context with handle, and add it to the list of active clients
285             // query primary services
286             printf("\nSearch for battery service.\n");
287             state = TC_W4_SERVICE_RESULT;
288             gatt_client_discover_primary_services_by_uuid16(handle_gatt_client_event, connection_handle, battery_service_uuid);
289             break;
290         case HCI_EVENT_DISCONNECTION_COMPLETE:
291 
292             if (cmdline_addr_found){
293                 printf("\nDisconnected %s\n", bd_addr_to_str(cmdline_addr));
294                 return;
295             }
296 
297             printf("\nDisconnected %s\n", bd_addr_to_str(report.address));
298             printf("Restart scan.\n");
299             state = TC_W4_SCAN_RESULT;
300             gap_start_scan();
301             break;
302         default:
303             break;
304     }
305 }
306 
307 #ifdef HAVE_POSIX_STDIN
308 static void usage(const char *name){
309     fprintf(stderr, "\nUsage: %s [-a|--address aa:bb:cc:dd:ee:ff]\n", name);
310     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");
311 }
312 #endif
313 
314 int btstack_main(int argc, const char * argv[]);
315 int btstack_main(int argc, const char * argv[]){
316 
317 #ifdef HAVE_POSIX_STDIN
318     int arg = 1;
319     cmdline_addr_found = 0;
320 
321     while (arg < argc) {
322         if(!strcmp(argv[arg], "-a") || !strcmp(argv[arg], "--address")){
323             arg++;
324             cmdline_addr_found = sscanf_bd_addr(argv[arg], cmdline_addr);
325             arg++;
326             if (!cmdline_addr_found) exit(1);
327             continue;
328         }
329         usage(argv[0]);
330         return 0;
331     }
332 #else
333     UNUSED(argc);
334     UNUSED(argv);
335 #endif
336 
337     hci_event_callback_registration.callback = &hci_event_handler;
338     hci_add_event_handler(&hci_event_callback_registration);
339 
340     l2cap_init();
341 
342     gatt_client_init();
343 
344     sm_init();
345     sm_set_io_capabilities(IO_CAPABILITY_NO_INPUT_NO_OUTPUT);
346 
347     // turn on!
348     hci_power_control(HCI_POWER_ON);
349 
350     return 0;
351 }
352 
353 
354 
355 
356