xref: /btstack/example/gatt_battery_query.c (revision ddaf35c7579ab4463891f4e60cea40b4398b142c)
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     int status;
144     uint8_t battery_level;
145 
146     switch(state){
147         case TC_W4_SERVICE_RESULT:
148             switch(hci_event_packet_get_type(packet)){
149                 case GATT_EVENT_SERVICE_QUERY_RESULT:
150                     gatt_event_service_query_result_get_service(packet, &battery_service);
151                     dump_service(&battery_service);
152                     break;
153                 case GATT_EVENT_QUERY_COMPLETE:
154                     if (packet[4] != 0){
155                         printf("SERVICE_QUERY_RESULT - Error status %x.\n", packet[4]);
156                         add_to_blacklist(report.address);
157                         gap_disconnect(connection_handle);
158                         break;
159                     }
160                     state = TC_W4_CHARACTERISTIC_RESULT;
161                     printf("\nSearch for battery level characteristic.\n");
162                     gatt_client_discover_characteristics_for_service_by_uuid16(handle_gatt_client_event, connection_handle, &battery_service, battery_level_characteristic_uuid);
163                     break;
164                 default:
165                     break;
166             }
167             break;
168 
169         case TC_W4_CHARACTERISTIC_RESULT:
170             switch(hci_event_packet_get_type(packet)){
171                 case GATT_EVENT_CHARACTERISTIC_QUERY_RESULT:
172                     gatt_event_characteristic_query_result_get_characteristic(packet, &config_characteristic);
173                     dump_characteristic(&config_characteristic);
174                     break;
175                 case GATT_EVENT_QUERY_COMPLETE:
176                     if (packet[4] != 0){
177                         printf("CHARACTERISTIC_QUERY_RESULT - Error status %x.\n", packet[4]);
178                         add_to_blacklist(report.address);
179                         gap_disconnect(connection_handle);
180                         break;
181                     }
182                     state = TC_W4_BATTERY_DATA;
183                     printf("\nConfigure battery level characteristic for notify.\n");
184                     status = gatt_client_write_client_characteristic_configuration(handle_gatt_client_event, connection_handle, &config_characteristic, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION);
185                     if (status != 0){
186                         printf("\nNotification not supported. Query value of characteristic.\n");
187                         gatt_client_read_value_of_characteristic(handle_gatt_client_event, connection_handle, &config_characteristic);
188                     }
189 
190                     break;
191                 default:
192                     break;
193             }
194             break;
195         case TC_W4_BATTERY_DATA:
196             switch(hci_event_packet_get_type(packet)){
197                 case GATT_EVENT_NOTIFICATION:
198                     printf("\nBattery Data:\n");
199                     dump_characteristic_value(&packet[8], little_endian_read_16(packet, 6));
200                     break;
201                 case GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT:
202 
203                         if (gatt_event_characteristic_value_query_result_get_value_length(packet) < 1) break;
204                         battery_level = gatt_event_characteristic_value_query_result_get_value(packet)[0];
205                         printf("Battry level %d \n", battery_level);
206                     break;
207 
208                 case GATT_EVENT_QUERY_COMPLETE:
209                     if (packet[4] != 0){
210                         printf("CHARACTERISTIC_VALUE_QUERY_RESULT - Error status %x.\n", packet[4]);
211                         break;
212                     }
213                     // Use timer if repeated request is needed and notification is not supperted
214                     gap_disconnect(connection_handle);
215                     break;
216                 default:
217                     printf("Unknown packet type %x\n", hci_event_packet_get_type(packet));
218                     break;
219             }
220             break;
221 
222         default:
223             printf("error\n");
224             break;
225     }
226 
227 }
228 
229 static void fill_advertising_report_from_packet(advertising_report_t * adv_report, uint8_t *packet){
230     gap_event_advertising_report_get_address(packet, adv_report->address);
231     adv_report->event_type = gap_event_advertising_report_get_advertising_event_type(packet);
232     adv_report->address_type = gap_event_advertising_report_get_address_type(packet);
233     adv_report->rssi = gap_event_advertising_report_get_rssi(packet);
234     adv_report->length = gap_event_advertising_report_get_data_length(packet);
235     adv_report->data = gap_event_advertising_report_get_data(packet);
236 }
237 
238 static void hci_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
239     if (packet_type != HCI_EVENT_PACKET) return;
240 
241     uint8_t event = hci_event_packet_get_type(packet);
242     switch (event) {
243         case BTSTACK_EVENT_STATE:
244             // BTstack activated, get started
245             if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) break;
246             if (cmdline_addr_found){
247                 printf("Connect to %s\n", bd_addr_to_str(cmdline_addr));
248                 state = TC_W4_CONNECT;
249                 gap_connect(cmdline_addr, 0);
250                 break;
251             }
252             printf("Start scanning!\n");
253             state = TC_W4_SCAN_RESULT;
254             gap_set_scan_parameters(0,0x0030, 0x0030);
255             gap_start_scan();
256             break;
257         case GAP_EVENT_ADVERTISING_REPORT:
258             if (state != TC_W4_SCAN_RESULT) return;
259             fill_advertising_report_from_packet(&report, packet);
260 
261             if (blacklist_contains(report.address)) {
262                 break;
263             }
264             dump_advertising_report(&report);
265             // stop scanning, and connect to the device
266             state = TC_W4_CONNECT;
267             gap_stop_scan();
268             printf("Stop scan. Connect to device with addr %s.\n", bd_addr_to_str(report.address));
269             gap_connect(report.address,report.address_type);
270 
271             break;
272         case HCI_EVENT_LE_META:
273             // wait for connection complete
274             if (hci_event_le_meta_get_subevent_code(packet) !=  HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break;
275             if (state != TC_W4_CONNECT) return;
276             connection_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
277             // initialize gatt client context with handle, and add it to the list of active clients
278             // query primary services
279             printf("\nSearch for battery service.\n");
280             state = TC_W4_SERVICE_RESULT;
281             gatt_client_discover_primary_services_by_uuid16(handle_gatt_client_event, connection_handle, battery_service_uuid);
282             break;
283         case HCI_EVENT_DISCONNECTION_COMPLETE:
284 
285             if (cmdline_addr_found){
286                 printf("\nDisconnected %s\n", bd_addr_to_str(cmdline_addr));
287                 exit(0);
288             }
289 
290             printf("\nDisconnected %s\n", bd_addr_to_str(report.address));
291             printf("Restart scan.\n");
292             state = TC_W4_SCAN_RESULT;
293             gap_start_scan();
294             break;
295         default:
296             break;
297     }
298 }
299 
300 static void usage(const char *name){
301     fprintf(stderr, "\nUsage: %s [-a|--address aa:bb:cc:dd:ee:ff]\n", name);
302     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");
303 }
304 
305 int btstack_main(int argc, const char * argv[]);
306 int btstack_main(int argc, const char * argv[]){
307 
308     int arg = 1;
309     cmdline_addr_found = 0;
310 
311     while (arg < argc) {
312         if(!strcmp(argv[arg], "-a") || !strcmp(argv[arg], "--address")){
313             arg++;
314             cmdline_addr_found = sscanf_bd_addr(argv[arg], cmdline_addr);
315             arg++;
316             if (!cmdline_addr_found) exit(1);
317             continue;
318         }
319         usage(argv[0]);
320         return 0;
321     }
322 
323     hci_event_callback_registration.callback = &hci_event_handler;
324     hci_add_event_handler(&hci_event_callback_registration);
325 
326     l2cap_init();
327 
328     gatt_client_init();
329 
330     sm_init();
331     sm_set_io_capabilities(IO_CAPABILITY_NO_INPUT_NO_OUTPUT);
332 
333     // turn on!
334     hci_power_control(HCI_POWER_ON);
335 
336     return 0;
337 }
338 
339 
340 
341 
342