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 BLUEKITCHEN
24 * GMBH 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__ "gap_inquiry.c"
39
40 // *****************************************************************************
41 /* EXAMPLE_START(gap_inquiry): GAP Classic Inquiry
42 *
43 * @text The Generic Access Profile (GAP) defines how Bluetooth devices discover
44 * and establish a connection with each other. In this example, the application
45 * discovers surrounding Bluetooth devices and collects their Class of Device
46 * (CoD), page scan mode, clock offset, and RSSI. After that, the remote name of
47 * each device is requested. In the following section we outline the Bluetooth
48 * logic part, i.e., how the packet handler handles the asynchronous events and
49 * data packets.
50 */
51 // *****************************************************************************
52
53 #include <stdint.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57
58 #include "btstack.h"
59
60 #define MAX_DEVICES 20
61 enum DEVICE_STATE { REMOTE_NAME_REQUEST, REMOTE_NAME_INQUIRED, REMOTE_NAME_FETCHED };
62 struct device {
63 bd_addr_t address;
64 uint8_t pageScanRepetitionMode;
65 uint16_t clockOffset;
66 enum DEVICE_STATE state;
67 };
68
69 #define INQUIRY_INTERVAL 5
70 struct device devices[MAX_DEVICES];
71 int deviceCount = 0;
72
73
74 enum STATE {INIT, ACTIVE} ;
75 enum STATE state = INIT;
76
77 static btstack_packet_callback_registration_t hci_event_callback_registration;
78
getDeviceIndexForAddress(bd_addr_t addr)79 static int getDeviceIndexForAddress( bd_addr_t addr){
80 int j;
81 for (j=0; j< deviceCount; j++){
82 if (bd_addr_cmp(addr, devices[j].address) == 0){
83 return j;
84 }
85 }
86 return -1;
87 }
88
start_scan(void)89 static void start_scan(void){
90 printf("Starting inquiry scan..\n");
91 gap_inquiry_start(INQUIRY_INTERVAL);
92 }
93
has_more_remote_name_requests(void)94 static int has_more_remote_name_requests(void){
95 int i;
96 for (i=0;i<deviceCount;i++) {
97 if (devices[i].state == REMOTE_NAME_REQUEST) return 1;
98 }
99 return 0;
100 }
101
do_next_remote_name_request(void)102 static void do_next_remote_name_request(void){
103 int i;
104 for (i=0;i<deviceCount;i++) {
105 // remote name request
106 if (devices[i].state == REMOTE_NAME_REQUEST){
107 devices[i].state = REMOTE_NAME_INQUIRED;
108 printf("Get remote name of %s...\n", bd_addr_to_str(devices[i].address));
109 gap_remote_name_request( devices[i].address, devices[i].pageScanRepetitionMode, devices[i].clockOffset | 0x8000);
110 return;
111 }
112 }
113 }
114
continue_remote_names(void)115 static void continue_remote_names(void){
116 if (has_more_remote_name_requests()){
117 do_next_remote_name_request();
118 return;
119 }
120 start_scan();
121 }
122
123 /* @section Bluetooth Logic
124 *
125 * @text The Bluetooth logic is implemented as a state machine within the packet
126 * handler. In this example, the following states are passed sequentially:
127 * INIT, and ACTIVE.
128 */
129
packet_handler(uint8_t packet_type,uint16_t channel,uint8_t * packet,uint16_t size)130 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
131 UNUSED(channel);
132 UNUSED(size);
133
134 bd_addr_t addr;
135 int i;
136 int index;
137
138 if (packet_type != HCI_EVENT_PACKET) return;
139
140 uint8_t event = hci_event_packet_get_type(packet);
141
142 switch(state){
143 /* @text In INIT, an inquiry scan is started, and the application transits to
144 * ACTIVE state.
145 */
146 case INIT:
147 switch(event){
148 case BTSTACK_EVENT_STATE:
149 if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING){
150 start_scan();
151 state = ACTIVE;
152 }
153 break;
154 default:
155 break;
156 }
157 break;
158
159 /* @text In ACTIVE, the following events are processed:
160 * - GAP Inquiry result event: BTstack provides a unified inquiry result that contain
161 * Class of Device (CoD), page scan mode, clock offset. RSSI and name (from EIR) are optional.
162 * - Inquiry complete event: the remote name is requested for devices without a fetched
163 * name. The state of a remote name can be one of the following:
164 * REMOTE_NAME_REQUEST, REMOTE_NAME_INQUIRED, or REMOTE_NAME_FETCHED.
165 * - Remote name request complete event: the remote name is stored in the table and the
166 * state is updated to REMOTE_NAME_FETCHED. The query of remote names is continued.
167 */
168 case ACTIVE:
169 switch(event){
170
171 case GAP_EVENT_INQUIRY_RESULT:
172 if (deviceCount >= MAX_DEVICES) break; // already full
173 gap_event_inquiry_result_get_bd_addr(packet, addr);
174 index = getDeviceIndexForAddress(addr);
175 if (index >= 0) break; // already in our list
176
177 memcpy(devices[deviceCount].address, addr, 6);
178 devices[deviceCount].pageScanRepetitionMode = gap_event_inquiry_result_get_page_scan_repetition_mode(packet);
179 devices[deviceCount].clockOffset = gap_event_inquiry_result_get_clock_offset(packet);
180 // print info
181 printf("Device found: %s ", bd_addr_to_str(addr));
182 printf("with COD: 0x%06x, ", (unsigned int) gap_event_inquiry_result_get_class_of_device(packet));
183 printf("pageScan %d, ", devices[deviceCount].pageScanRepetitionMode);
184 printf("clock offset 0x%04x",devices[deviceCount].clockOffset);
185 if (gap_event_inquiry_result_get_rssi_available(packet)){
186 printf(", rssi %d dBm", (int8_t) gap_event_inquiry_result_get_rssi(packet));
187 }
188 if (gap_event_inquiry_result_get_name_available(packet)){
189 char name_buffer[240];
190 int name_len = gap_event_inquiry_result_get_name_len(packet);
191 memcpy(name_buffer, gap_event_inquiry_result_get_name(packet), name_len);
192 name_buffer[name_len] = 0;
193 printf(", name '%s'", name_buffer);
194 devices[deviceCount].state = REMOTE_NAME_FETCHED;;
195 } else {
196 devices[deviceCount].state = REMOTE_NAME_REQUEST;
197 }
198 printf("\n");
199 deviceCount++;
200 break;
201
202 case GAP_EVENT_INQUIRY_COMPLETE:
203 for (i=0;i<deviceCount;i++) {
204 // retry remote name request
205 if (devices[i].state == REMOTE_NAME_INQUIRED)
206 devices[i].state = REMOTE_NAME_REQUEST;
207 }
208 continue_remote_names();
209 break;
210
211 case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
212 reverse_bd_addr(&packet[3], addr);
213 index = getDeviceIndexForAddress(addr);
214 if (index >= 0) {
215 if (packet[2] == 0) {
216 printf("Name: '%s'\n", &packet[9]);
217 devices[index].state = REMOTE_NAME_FETCHED;
218 } else {
219 printf("Failed to get name: page timeout\n");
220 }
221 }
222 continue_remote_names();
223 break;
224
225 default:
226 break;
227 }
228 break;
229
230 default:
231 break;
232 }
233 }
234
235 /* @text For more details on discovering remote devices, please see
236 * Section on [GAP](../profiles/#sec:GAPdiscoverRemoteDevices).
237 */
238
239
240 /* @section Main Application Setup
241 *
242 * @text Listing MainConfiguration shows main application code.
243 * It registers the HCI packet handler and starts the Bluetooth stack.
244 */
245
246 /* LISTING_START(MainConfiguration): Setup packet handler for GAP inquiry */
247 int btstack_main(int argc, const char * argv[]);
btstack_main(int argc,const char * argv[])248 int btstack_main(int argc, const char * argv[]) {
249 (void)argc;
250 (void)argv;
251
252 // enabled EIR
253 hci_set_inquiry_mode(INQUIRY_MODE_RSSI_AND_EIR);
254
255 hci_event_callback_registration.callback = &packet_handler;
256 hci_add_event_handler(&hci_event_callback_registration);
257
258 // turn on!
259 hci_power_control(HCI_POWER_ON);
260
261 return 0;
262 }
263 /* LISTING_END */
264 /* EXAMPLE_END */
265