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_browser.c" 39 40 // ***************************************************************************** 41 /* EXAMPLE_START(gatt_browser): GATT Client - Discovering primary services and their characteristics 42 * 43 * @text This example shows how to use the GATT Client 44 * API to discover primary services and their characteristics of the first found 45 * device that is advertising its services. 46 * 47 * The logic is divided between the HCI and GATT client packet handlers. 48 * The HCI packet handler is responsible for finding a remote device, 49 * connecting to it, and for starting the first GATT client query. 50 * Then, the GATT client packet handler receives all primary services and 51 * requests the characteristics of the last one to keep the example short. 52 * 53 */ 54 // ***************************************************************************** 55 56 #include <stdint.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <string.h> 60 61 #include "btstack.h" 62 #include "gatt_browser.h" 63 64 typedef struct advertising_report { 65 uint8_t type; 66 uint8_t event_type; 67 uint8_t address_type; 68 bd_addr_t address; 69 uint8_t rssi; 70 uint8_t length; 71 const uint8_t * data; 72 } advertising_report_t; 73 74 static bd_addr_t cmdline_addr; 75 static int cmdline_addr_found = 0; 76 77 static hci_con_handle_t connection_handler; 78 static gatt_client_service_t services[40]; 79 static int service_count = 0; 80 static int service_index = 0; 81 82 static btstack_packet_callback_registration_t hci_event_callback_registration; 83 84 /* @section GATT client setup 85 * 86 * @text In the setup phase, a GATT client must register the HCI and GATT client 87 * packet handlers, as shown in Listing GATTClientSetup. 88 * Additionally, the security manager can be setup, if signed writes, or 89 * encrypted, or authenticated connection are required, to access the 90 * characteristics, as explained in Section on [SMP](../protocols/#sec:smpProtocols). 91 */ 92 93 /* LISTING_START(GATTClientSetup): Setting up GATT client */ 94 95 // Handles connect, disconnect, and advertising report events, 96 // starts the GATT client, and sends the first query. 97 static void handle_hci_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 98 99 // Handles GATT client query results, sends queries and the 100 // GAP disconnect command when the querying is done. 101 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 102 103 static void gatt_client_setup(void){ 104 105 // Initialize L2CAP and register HCI event handler 106 l2cap_init(); 107 108 // Initialize GATT client 109 gatt_client_init(); 110 111 // Optinoally, Setup security manager 112 sm_init(); 113 sm_set_io_capabilities(IO_CAPABILITY_NO_INPUT_NO_OUTPUT); 114 115 // register for HCI events 116 hci_event_callback_registration.callback = &handle_hci_event; 117 hci_add_event_handler(&hci_event_callback_registration); 118 } 119 /* LISTING_END */ 120 121 static void printUUID(uint8_t * uuid128, uint16_t uuid16){ 122 if (uuid16){ 123 printf("%04x",uuid16); 124 } else { 125 printf("%s", uuid128_to_str(uuid128)); 126 } 127 } 128 129 static void dump_advertising_report(advertising_report_t * e){ 130 printf(" * adv. event: evt-type %u, addr-type %u, addr %s, rssi %u, length adv %u, data: ", e->event_type, 131 e->address_type, bd_addr_to_str(e->address), e->rssi, e->length); 132 printf_hexdump(e->data, e->length); 133 134 } 135 136 static void dump_characteristic(gatt_client_characteristic_t * characteristic){ 137 printf(" * characteristic: [0x%04x-0x%04x-0x%04x], properties 0x%02x, uuid ", 138 characteristic->start_handle, characteristic->value_handle, characteristic->end_handle, characteristic->properties); 139 printUUID(characteristic->uuid128, characteristic->uuid16); 140 printf("\n"); 141 } 142 143 static void dump_service(gatt_client_service_t * service){ 144 printf(" * service: [0x%04x-0x%04x], uuid ", service->start_group_handle, service->end_group_handle); 145 printUUID(service->uuid128, service->uuid16); 146 printf("\n"); 147 } 148 149 static void fill_advertising_report_from_packet(advertising_report_t * report, uint8_t *packet){ 150 gap_event_advertising_report_get_address(packet, report->address); 151 report->event_type = gap_event_advertising_report_get_advertising_event_type(packet); 152 report->address_type = gap_event_advertising_report_get_address_type(packet); 153 report->rssi = gap_event_advertising_report_get_rssi(packet); 154 report->length = gap_event_advertising_report_get_data_length(packet); 155 report->data = gap_event_advertising_report_get_data(packet); 156 } 157 158 /* @section HCI packet handler 159 * 160 * @text The HCI packet handler has to start the scanning, 161 * to find the first advertising device, to stop scanning, to connect 162 * to and later to disconnect from it, to start the GATT client upon 163 * the connection is completed, and to send the first query - in this 164 * case the gatt_client_discover_primary_services() is called, see 165 * Listing GATTBrowserHCIPacketHandler. 166 */ 167 168 /* LISTING_START(GATTBrowserHCIPacketHandler): Connecting and disconnecting from the GATT client */ 169 static void handle_hci_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 170 UNUSED(channel); 171 UNUSED(size); 172 173 if (packet_type != HCI_EVENT_PACKET) return; 174 advertising_report_t report; 175 176 uint8_t event = hci_event_packet_get_type(packet); 177 switch (event) { 178 case BTSTACK_EVENT_STATE: 179 // BTstack activated, get started 180 if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) break; 181 if (cmdline_addr_found){ 182 printf("Trying to connect to %s\n", bd_addr_to_str(cmdline_addr)); 183 gap_connect(cmdline_addr, 0); 184 break; 185 } 186 printf("BTstack activated, start scanning!\n"); 187 gap_set_scan_parameters(0,0x0030, 0x0030); 188 gap_start_scan(); 189 break; 190 case GAP_EVENT_ADVERTISING_REPORT: 191 fill_advertising_report_from_packet(&report, packet); 192 dump_advertising_report(&report); 193 194 // stop scanning, and connect to the device 195 gap_stop_scan(); 196 gap_connect(report.address,report.address_type); 197 break; 198 case HCI_EVENT_LE_META: 199 // wait for connection complete 200 if (hci_event_le_meta_get_subevent_code(packet) != HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break; 201 connection_handler = hci_subevent_le_connection_complete_get_connection_handle(packet); 202 // query primary services 203 gatt_client_discover_primary_services(handle_gatt_client_event, connection_handler); 204 break; 205 case HCI_EVENT_DISCONNECTION_COMPLETE: 206 printf("\nGATT browser - DISCONNECTED\n"); 207 break; 208 default: 209 break; 210 } 211 } 212 /* LISTING_END */ 213 214 /* @section GATT Client event handler 215 * 216 * @text Query results and further queries are handled by the GATT client packet 217 * handler, as shown in Listing GATTBrowserQueryHandler. Here, upon 218 * receiving the primary services, the 219 * gatt_client_discover_characteristics_for_service() query for the last 220 * received service is sent. After receiving the characteristics for the service, 221 * gap_disconnect is called to terminate the connection. Upon 222 * disconnect, the HCI packet handler receives the disconnect complete event. 223 */ 224 225 /* LISTING_START(GATTBrowserQueryHandler): Handling of the GATT client queries */ 226 static int search_services = 1; 227 228 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 229 UNUSED(packet_type); 230 UNUSED(channel); 231 UNUSED(size); 232 233 gatt_client_service_t service; 234 gatt_client_characteristic_t characteristic; 235 switch(hci_event_packet_get_type(packet)){ 236 case GATT_EVENT_SERVICE_QUERY_RESULT:\ 237 gatt_event_service_query_result_get_service(packet, &service); 238 dump_service(&service); 239 services[service_count++] = service; 240 break; 241 case GATT_EVENT_CHARACTERISTIC_QUERY_RESULT: 242 gatt_event_characteristic_query_result_get_characteristic(packet, &characteristic); 243 dump_characteristic(&characteristic); 244 break; 245 case GATT_EVENT_QUERY_COMPLETE: 246 if (search_services){ 247 // GATT_EVENT_QUERY_COMPLETE of search services 248 service_index = 0; 249 printf("\nGATT browser - CHARACTERISTIC for SERVICE %s\n", uuid128_to_str(service.uuid128)); 250 search_services = 0; 251 gatt_client_discover_characteristics_for_service(handle_gatt_client_event, connection_handler, &services[service_index]); 252 } else { 253 // GATT_EVENT_QUERY_COMPLETE of search characteristics 254 if (service_index < service_count) { 255 service = services[service_index++]; 256 printf("\nGATT browser - CHARACTERISTIC for SERVICE %s, [0x%04x-0x%04x]\n", 257 uuid128_to_str(service.uuid128), service.start_group_handle, service.end_group_handle); 258 gatt_client_discover_characteristics_for_service(handle_gatt_client_event, connection_handler, &service); 259 break; 260 } 261 service_index = 0; 262 gap_disconnect(connection_handler); 263 } 264 break; 265 default: 266 break; 267 } 268 } 269 /* LISTING_END */ 270 271 #ifdef HAVE_BTSTACK_STDIN 272 static void usage(const char *name){ 273 fprintf(stderr, "\nUsage: %s [-a|--address aa:bb:cc:dd:ee:ff]\n", name); 274 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"); 275 } 276 #endif 277 278 int btstack_main(int argc, const char * argv[]); 279 int btstack_main(int argc, const char * argv[]){ 280 281 #ifdef HAVE_BTSTACK_STDIN 282 int arg = 1; 283 cmdline_addr_found = 0; 284 285 while (arg < argc) { 286 if(!strcmp(argv[arg], "-a") || !strcmp(argv[arg], "--address")){ 287 arg++; 288 cmdline_addr_found = sscanf_bd_addr(argv[arg], cmdline_addr); 289 arg++; 290 continue; 291 } 292 usage(argv[0]); 293 return 0; 294 } 295 #else 296 (void)argc; 297 (void)argv; 298 #endif 299 300 // setup GATT client 301 gatt_client_setup(); 302 303 // setup ATT server - only needed if LE Peripheral does ATT queries on its own, e.g. Android and iOS 304 att_server_init(profile_data, NULL, NULL); 305 306 // turn on! 307 hci_power_control(HCI_POWER_ON); 308 309 return 0; 310 } 311 312 /* EXAMPLE_END */ 313 314 315