xref: /btstack/src/ble/gatt_client.h (revision 180cbe7900dfeabef5d64313a6927fe6bf94cb60)
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37 
38 /**
39  * @title GATT Client
40  *
41  */
42 
43 #ifndef btstack_gatt_client_h
44 #define btstack_gatt_client_h
45 
46 #include "hci.h"
47 
48 #if defined __cplusplus
49 extern "C" {
50 #endif
51 
52 typedef enum {
53     P_READY,
54     P_W2_SEND_SERVICE_QUERY,
55     P_W4_SERVICE_QUERY_RESULT,
56     P_W2_SEND_SERVICE_WITH_UUID_QUERY,
57     P_W4_SERVICE_WITH_UUID_RESULT,
58 
59     P_W2_SEND_ALL_CHARACTERISTICS_OF_SERVICE_QUERY,
60     P_W4_ALL_CHARACTERISTICS_OF_SERVICE_QUERY_RESULT,
61     P_W2_SEND_CHARACTERISTIC_WITH_UUID_QUERY,
62     P_W4_CHARACTERISTIC_WITH_UUID_QUERY_RESULT,
63 
64     P_W2_SEND_ALL_CHARACTERISTIC_DESCRIPTORS_QUERY,
65     P_W4_ALL_CHARACTERISTIC_DESCRIPTORS_QUERY_RESULT,
66 
67     P_W2_SEND_INCLUDED_SERVICE_QUERY,
68     P_W4_INCLUDED_SERVICE_QUERY_RESULT,
69     P_W2_SEND_INCLUDED_SERVICE_WITH_UUID_QUERY,
70     P_W4_INCLUDED_SERVICE_UUID_WITH_QUERY_RESULT,
71 
72     P_W2_SEND_READ_CHARACTERISTIC_VALUE_QUERY,
73     P_W4_READ_CHARACTERISTIC_VALUE_RESULT,
74 
75     P_W2_SEND_READ_BLOB_QUERY,
76     P_W4_READ_BLOB_RESULT,
77 
78     P_W2_SEND_READ_BY_TYPE_REQUEST,
79     P_W4_READ_BY_TYPE_RESPONSE,
80 
81     P_W2_SEND_READ_MULTIPLE_REQUEST,
82     P_W4_READ_MULTIPLE_RESPONSE,
83 
84     P_W2_SEND_READ_MULTIPLE_VARIABLE_REQUEST,
85     P_W4_READ_MULTIPLE_VARIABLE_RESPONSE,
86 
87     P_W2_SEND_WRITE_CHARACTERISTIC_VALUE,
88     P_W4_WRITE_CHARACTERISTIC_VALUE_RESULT,
89 
90     P_W2_PREPARE_WRITE,
91     P_W4_PREPARE_WRITE_RESULT,
92     P_W2_PREPARE_RELIABLE_WRITE,
93     P_W4_PREPARE_RELIABLE_WRITE_RESULT,
94 
95     P_W2_EXECUTE_PREPARED_WRITE,
96     P_W4_EXECUTE_PREPARED_WRITE_RESULT,
97     P_W2_CANCEL_PREPARED_WRITE,
98     P_W4_CANCEL_PREPARED_WRITE_RESULT,
99     P_W2_CANCEL_PREPARED_WRITE_DATA_MISMATCH,
100     P_W4_CANCEL_PREPARED_WRITE_DATA_MISMATCH_RESULT,
101 
102 #ifdef ENABLE_GATT_FIND_INFORMATION_FOR_CCC_DISCOVERY
103     P_W2_SEND_FIND_CLIENT_CHARACTERISTIC_CONFIGURATION_QUERY,
104     P_W4_FIND_CLIENT_CHARACTERISTIC_CONFIGURATION_QUERY_RESULT,
105 #else
106     P_W2_SEND_READ_CLIENT_CHARACTERISTIC_CONFIGURATION_QUERY,
107     P_W4_READ_CLIENT_CHARACTERISTIC_CONFIGURATION_QUERY_RESULT,
108 #endif
109     P_W2_WRITE_CLIENT_CHARACTERISTIC_CONFIGURATION,
110     P_W4_CLIENT_CHARACTERISTIC_CONFIGURATION_RESULT,
111 
112     P_W2_SEND_READ_CHARACTERISTIC_DESCRIPTOR_QUERY,
113     P_W4_READ_CHARACTERISTIC_DESCRIPTOR_RESULT,
114 
115     P_W2_SEND_READ_BLOB_CHARACTERISTIC_DESCRIPTOR_QUERY,
116     P_W4_READ_BLOB_CHARACTERISTIC_DESCRIPTOR_RESULT,
117 
118     P_W2_SEND_WRITE_CHARACTERISTIC_DESCRIPTOR,
119     P_W4_WRITE_CHARACTERISTIC_DESCRIPTOR_RESULT,
120 
121     // all long writes use this
122     P_W2_PREPARE_WRITE_CHARACTERISTIC_DESCRIPTOR,
123     P_W4_PREPARE_WRITE_CHARACTERISTIC_DESCRIPTOR_RESULT,
124     P_W2_EXECUTE_PREPARED_WRITE_CHARACTERISTIC_DESCRIPTOR,
125     P_W4_EXECUTE_PREPARED_WRITE_CHARACTERISTIC_DESCRIPTOR_RESULT,
126 
127     // gatt reliable write API use this (manual version of the above)
128     P_W2_PREPARE_WRITE_SINGLE,
129     P_W4_PREPARE_WRITE_SINGLE_RESULT,
130 
131     P_W4_IDENTITY_RESOLVING,
132     P_W4_CMAC_READY,
133     P_W4_CMAC_RESULT,
134     P_W2_SEND_SIGNED_WRITE,
135     P_W4_SEND_SINGED_WRITE_DONE,
136 
137     P_W2_SDP_QUERY,
138     P_W4_SDP_QUERY,
139     P_W2_L2CAP_CONNECT,
140     P_W4_L2CAP_CONNECTION,
141     P_W2_EMIT_CONNECTED,
142 } gatt_client_state_t;
143 
144 
145 typedef enum{
146     SEND_MTU_EXCHANGE,
147     SENT_MTU_EXCHANGE,
148     MTU_EXCHANGED,
149     MTU_AUTO_EXCHANGE_DISABLED
150 } gatt_client_mtu_t;
151 
152 #ifdef ENABLE_GATT_OVER_EATT
153 typedef enum {
154     GATT_CLIENT_EATT_IDLE,
155     GATT_CLIENT_EATT_DISCOVER_GATT_SERVICE_W2_SEND,
156     GATT_CLIENT_EATT_DISCOVER_GATT_SERVICE_W4_DONE,
157     GATT_CLIENT_EATT_READ_SERVER_SUPPORTED_FEATURES_W2_SEND,
158     GATT_CLIENT_EATT_READ_SERVER_SUPPORTED_FEATURES_W4_DONE,
159     GATT_CLIENT_EATT_FIND_CLIENT_SUPPORTED_FEATURES_W2_SEND,
160     GATT_CLIENT_EATT_FIND_CLIENT_SUPPORTED_FEATURES_W4_DONE,
161     GATT_CLIENT_EATT_WRITE_ClIENT_SUPPORTED_FEATURES_W2_SEND,
162     GATT_CLIENT_EATT_WRITE_ClIENT_SUPPORTED_FEATURES_W4_DONE,
163     GATT_CLIENT_EATT_L2CAP_SETUP,
164     GATT_CLIENT_EATT_READY,
165 } gatt_client_eatt_state_t;
166 #endif
167 
168 typedef struct gatt_client{
169     btstack_linked_item_t    item;
170     // TODO: rename gatt_client_state -> state
171     gatt_client_state_t state;
172 
173     // user callback
174     btstack_packet_handler_t callback;
175 
176     // can write without response callback
177     btstack_packet_handler_t write_without_response_callback;
178 
179     // can write without response requests
180     btstack_linked_list_t write_without_response_requests;
181 
182     // regular gatt query requests
183     btstack_linked_list_t query_requests;
184 
185     hci_con_handle_t con_handle;
186 
187     att_bearer_type_t bearer_type;
188 
189 #ifdef ENABLE_GATT_OVER_CLASSIC
190     bd_addr_t addr;
191     uint16_t  l2cap_psm;
192     uint16_t  l2cap_cid;
193     btstack_context_callback_registration_t callback_request;
194 #endif
195 
196 #ifdef ENABLE_GATT_OVER_EATT
197     gatt_client_eatt_state_t eatt_state;
198     btstack_linked_list_t eatt_clients;
199     uint8_t * eatt_storage_buffer;
200     uint16_t eatt_storage_size;
201     uint8_t  eatt_num_clients;
202     uint8_t  gatt_server_supported_features;
203     uint16_t gatt_service_start_group_handle;
204     uint16_t gatt_service_end_group_handle;
205     uint16_t gatt_client_supported_features_handle;
206 #endif
207 
208     uint16_t          mtu;
209     gatt_client_mtu_t mtu_state;
210 
211     uint16_t uuid16;
212     uint8_t  uuid128[16];
213 
214     uint16_t start_group_handle;
215     uint16_t end_group_handle;
216 
217     uint16_t query_start_handle;
218     uint16_t query_end_handle;
219 
220     uint8_t  characteristic_properties;
221     uint16_t characteristic_start_handle;
222 
223     uint16_t attribute_handle;
224     uint16_t attribute_offset;
225     uint16_t attribute_length;
226     uint8_t* attribute_value;
227 
228     // read multiple characteristic values
229     uint16_t    read_multiple_handle_count;
230     uint16_t  * read_multiple_handles;
231 
232     uint16_t client_characteristic_configuration_handle;
233     uint8_t  client_characteristic_configuration_value[2];
234 
235     uint8_t  filter_with_uuid;
236     uint8_t  send_confirmation;
237 
238     int      le_device_index;
239     uint8_t  cmac[8];
240 
241     btstack_timer_source_t gc_timeout;
242 
243     uint8_t  security_counter;
244     uint8_t  wait_for_authentication_complete;
245     uint8_t  pending_error_code;
246 
247     bool     reencryption_active;
248     uint8_t  reencryption_result;
249 
250     gap_security_level_t security_level;
251 
252 } gatt_client_t;
253 
254 typedef struct gatt_client_notification {
255     btstack_linked_item_t    item;
256     btstack_packet_handler_t callback;
257     hci_con_handle_t con_handle;
258     uint16_t attribute_handle;
259 } gatt_client_notification_t;
260 
261 /* API_START */
262 
263 typedef struct {
264     uint16_t start_group_handle;
265     uint16_t end_group_handle;
266     uint16_t uuid16;
267     uint8_t  uuid128[16];
268 } gatt_client_service_t;
269 
270 typedef struct {
271     uint16_t start_handle;
272     uint16_t value_handle;
273     uint16_t end_handle;
274     uint16_t properties;
275     uint16_t uuid16;
276     uint8_t  uuid128[16];
277 } gatt_client_characteristic_t;
278 
279 typedef struct {
280     uint16_t handle;
281     uint16_t uuid16;
282     uint8_t  uuid128[16];
283 } gatt_client_characteristic_descriptor_t;
284 
285 /**
286  * @brief Set up GATT client.
287  */
288 void gatt_client_init(void);
289 
290 /**
291  * @brief Set minimum required security level for GATT Client
292  * @note  The Bluetooth specification makes the GATT Server responsible to check for security.
293  *        This allows an attacker to spoof an existing device with a GATT Servers, but skip the authentication part.
294  *        If your application is exchanging sensitive data with a remote device, you would need to manually check
295  *        the security level before sending/receive such data.
296  *        With level > 0, the GATT Client triggers authentication for all GATT Requests and defers any exchange
297  *        until the required security level is established.
298  *        gatt_client_request_can_write_without_response_event does not trigger authentication
299  *        gatt_client_request_to_write_without_response does not trigger authentication
300  *  @pram level, default LEVEL_0 (no encryption required)
301  */
302 void gatt_client_set_required_security_level(gap_security_level_t level);
303 
304 /**
305  * @brief Connect to remote GATT Server over Classic (BR/EDR) Connection
306  *        GATT_EVENT_CONNECTED with status and con_handle for other API functions
307  *        is emitted on connection complete.
308  * @note requires ENABLE_GATT_OVER_CLASSIC.
309  * @param addr
310  * @return status
311  */
312 uint8_t gatt_client_classic_connect(btstack_packet_handler_t callback, bd_addr_t addr);
313 
314 /**
315  * @brief Disconnect o Classic (BR/EDR) connection to a remote GATT Server
316  * @note requires ENABLE_GATT_OVER_CLASSIC
317  * @param con_handle
318  * @return status
319  */
320 uint8_t gatt_client_classic_disconnect(btstack_packet_handler_t callback, hci_con_handle_t con_handle);
321 
322 /**
323  * @brief Setup Enhanced LE Bearer with up to 5 channels on existing LE connection
324  * @param callback for GATT_EVENT_CONNECTED and GATT_EVENT_DISCONNECTED events
325  * @param con_handle
326  * @param num_channels
327  * @param storage_buffer for L2CAP connection
328  * @param storage_size - each channel requires (2 * ATT MTU) + 10 bytes
329  * @return
330  */
331 uint8_t gatt_client_le_enhanced_connect(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint8_t num_channels, uint8_t * storage_buffer, uint16_t storage_size);
332 
333 /**
334  * @brief MTU is available after the first query has completed. If status is equal to ERROR_CODE_SUCCESS, it returns the real value,
335  * otherwise the default value ATT_DEFAULT_MTU (see bluetooth.h).
336  * @param  con_handle
337  * @param  mtu
338  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
339  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
340  *                GATT_CLIENT_IN_WRONG_STATE                                if MTU is not exchanged and MTU auto-exchange is disabled
341  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
342  */
343 uint8_t gatt_client_get_mtu(hci_con_handle_t con_handle, uint16_t * mtu);
344 
345 /**
346  * @brief Sets whether a MTU Exchange Request shall be automatically send before the
347  * first attribute read request is send. Default is enabled.
348  * @param enabled
349  */
350 void gatt_client_mtu_enable_auto_negotiation(uint8_t enabled);
351 
352 /**
353  * @brief Sends a MTU Exchange Request, this allows for the client to exchange MTU
354  * when gatt_client_mtu_enable_auto_negotiation is disabled.
355  * @param  callback
356  * @param  con_handle
357  */
358 void gatt_client_send_mtu_negotiation(btstack_packet_handler_t callback, hci_con_handle_t con_handle);
359 
360 /**
361  * @brief Returns 1 if the GATT client is ready to receive a query. It is used with daemon.
362  * @param  con_handle
363  * @return is_ready_status     0 - if no GATT client for con_handle is found, or is not ready, otherwise 1
364  */
365 int gatt_client_is_ready(hci_con_handle_t con_handle);
366 
367 /**
368  * @brief Discovers all primary services.
369  * For each found service a GATT_EVENT_SERVICE_QUERY_RESULT event will be emitted.
370  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
371  * @param  callback
372  * @param  con_handle
373  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
374  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
375  *                ERROR_CODE_SUCCESS         , if query is successfully registered
376  */
377 uint8_t gatt_client_discover_primary_services(btstack_packet_handler_t callback, hci_con_handle_t con_handle);
378 
379 /**
380  * @brief Discovers all secondary services.
381  * For each found service a GATT_EVENT_SERVICE_QUERY_RESULT event will be emitted.
382  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
383  * @param  callback
384  * @param  con_handle
385  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
386  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
387  *                ERROR_CODE_SUCCESS         , if query is successfully registered
388  */
389 uint8_t gatt_client_discover_secondary_services(btstack_packet_handler_t callback, hci_con_handle_t con_handle);
390 
391 /**
392  * @brief Discovers a specific primary service given its UUID. This service may exist multiple times.
393  * For each found service a GATT_EVENT_SERVICE_QUERY_RESULT event will be emitted.
394  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
395  * @param callback
396  * @param con_handle
397  * @param uuid16
398  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
399  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
400  *                ERROR_CODE_SUCCESS         , if query is successfully registered
401  */
402 uint8_t gatt_client_discover_primary_services_by_uuid16(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t uuid16);
403 
404 /**
405  * @brief Discovers a specific primary service given its UUID. This service may exist multiple times.
406  * For each found service a GATT_EVENT_SERVICE_QUERY_RESULT event will be emitted.
407  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
408  * @param  callback
409  * @param  con_handle
410  * @param  uuid128
411  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
412  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
413  *                ERROR_CODE_SUCCESS         , if query is successfully registered
414  */
415 uint8_t gatt_client_discover_primary_services_by_uuid128(btstack_packet_handler_t callback, hci_con_handle_t con_handle, const uint8_t * uuid128);
416 
417 /**
418  * @brief Finds included services within the specified service.
419  * For each found included service a GATT_EVENT_INCLUDED_SERVICE_QUERY_RESULT event will be emitted.
420  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
421  * Information about included service type (primary/secondary) can be retrieved either by sending
422  * an ATT find information request for the returned start group handle
423  * (returning the handle and the UUID for primary or secondary service) or by comparing the service
424  * to the list of all primary services.
425  * @param  callback
426  * @param  con_handle
427  * @param  service
428  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
429  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
430  *                ERROR_CODE_SUCCESS         , if query is successfully registered
431  */
432 uint8_t gatt_client_find_included_services_for_service(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_service_t * service);
433 
434 /**
435  * @brief Discovers all characteristics within the specified service.
436  * For each found characteristic a GATT_EVENT_CHARACTERISTIC_QUERY_RESULT event will be emited.
437  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
438  * @param  callback
439  * @param  con_handle
440  * @param  service
441  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
442  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
443  *                ERROR_CODE_SUCCESS         , if query is successfully registered
444  */
445 uint8_t gatt_client_discover_characteristics_for_service(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_service_t * service);
446 
447 /**
448  * @brief The following four functions are used to discover all characteristics within
449  * the specified service or handle range, and return those that match the given UUID.
450  *
451  * For each found characteristic a GATT_EVENT_CHARACTERISTIC_QUERY_RESULT event will emitted.
452  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
453  * @param  callback
454  * @param  con_handle
455  * @param  start_handle
456  * @param  end_handle
457  * @param  uuid16
458  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
459  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
460  *                ERROR_CODE_SUCCESS         , if query is successfully registered
461  */
462 uint8_t gatt_client_discover_characteristics_for_handle_range_by_uuid16(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t start_handle, uint16_t end_handle, uint16_t uuid16);
463 
464 /**
465  * @brief The following four functions are used to discover all characteristics within the
466  * specified service or handle range, and return those that match the given UUID.
467  * For each found characteristic a GATT_EVENT_CHARACTERISTIC_QUERY_RESULT event will emitted.
468  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
469  * @param  callback
470  * @param  con_handle
471  * @param  start_handle
472  * @param  end_handle
473  * @param  uuid128
474  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
475  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
476  *                ERROR_CODE_SUCCESS         , if query is successfully registered
477  */
478 uint8_t gatt_client_discover_characteristics_for_handle_range_by_uuid128(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128);
479 
480 /**
481  * @brief The following four functions are used to discover all characteristics within the
482  * specified service or handle range, and return those that match the given UUID.
483  * For each found characteristic a GATT_EVENT_CHARACTERISTIC_QUERY_RESULT event will emitted.
484  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
485  * @param  callback
486  * @param  con_handle
487  * @param  service
488  * @param  uuid16
489  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
490  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
491  *                ERROR_CODE_SUCCESS         , if query is successfully registered
492  */
493 uint8_t gatt_client_discover_characteristics_for_service_by_uuid16(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_service_t * service, uint16_t uuid16);
494 
495 /**
496  * @brief The following four functions are used to discover all characteristics within the
497  * specified service or handle range, and return those that match the given UUID.
498  * For each found characteristic a GATT_EVENT_CHARACTERISTIC_QUERY_RESULT event will emitted.
499  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
500  * @param  callback
501  * @param  con_handle
502  * @param  service
503  * @param  uuid128
504  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
505  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
506  *                ERROR_CODE_SUCCESS         , if query is successfully registered
507  */
508 uint8_t gatt_client_discover_characteristics_for_service_by_uuid128(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_service_t * service, const uint8_t * uuid128);
509 
510 /**
511  * @brief Discovers attribute handle and UUID of a characteristic descriptor within the specified characteristic.
512  * For each found descriptor a GATT_EVENT_ALL_CHARACTERISTIC_DESCRIPTORS_QUERY_RESULT event will be emitted.
513  *
514  * The GATT_EVENT_QUERY_COMPLETE event marks the end of discovery.
515  * @param  callback
516  * @param  con_handle
517  * @param  characteristic
518  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
519  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
520  *                ERROR_CODE_SUCCESS         , if query is successfully registered
521  */
522 uint8_t gatt_client_discover_characteristic_descriptors(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_t * characteristic);
523 
524 /**
525  * @brief Reads the characteristic value using the characteristic's value handle.
526  * If the characteristic value is found a GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT event will be emitted.
527  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
528  * @param  callback
529  * @param  con_handle
530  * @param  characteristic
531  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
532  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
533  *                ERROR_CODE_SUCCESS         , if query is successfully registered
534  */
535 uint8_t gatt_client_read_value_of_characteristic(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_t * characteristic);
536 
537 /**
538  * @brief Reads the characteristic value using the characteristic's value handle.
539  * If the characteristic value is found a GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT event will be emitted.
540  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
541  * @param  callback
542  * @param  con_handle
543  * @param  value_handle
544  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
545  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
546  *                ERROR_CODE_SUCCESS         , if query is successfully registered
547  */
548 uint8_t gatt_client_read_value_of_characteristic_using_value_handle(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle);
549 
550 /**
551  * @brief Reads the characteric value of all characteristics with the uuid.
552  * For each characteristic value found a GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT event will be emitted.
553  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
554  * @param  callback
555  * @param  con_handle
556  * @param  start_handle
557  * @param  end_handle
558  * @param  uuid16
559  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
560  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
561  *                ERROR_CODE_SUCCESS         , if query is successfully registered
562  */
563 uint8_t gatt_client_read_value_of_characteristics_by_uuid16(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t start_handle, uint16_t end_handle, uint16_t uuid16);
564 
565 /**
566  * @brief Reads the characteric value of all characteristics with the uuid.
567  * For each characteristic value found a GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT event will be emitted.
568  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
569  * @param  callback
570  * @param  con_handle
571  * @param  start_handle
572  * @param  end_handle
573  * @param  uuid128
574  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
575  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
576  *                ERROR_CODE_SUCCESS         , if query is successfully registered
577  */
578 uint8_t gatt_client_read_value_of_characteristics_by_uuid128(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128);
579 
580 /**
581  * @brief Reads the long characteristic value using the characteristic's value handle.
582  * The value will be returned in several blobs.
583  * For each blob, a GATT_EVENT_LONG_CHARACTERISTIC_VALUE_QUERY_RESULT event with updated value offset will be emitted.
584  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
585  * @param  callback
586  * @param  con_handle
587  * @param  characteristic
588  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
589  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
590  *                ERROR_CODE_SUCCESS         , if query is successfully registered
591  */
592 uint8_t gatt_client_read_long_value_of_characteristic(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_t * characteristic);
593 
594 /**
595  * @brief Reads the long characteristic value using the characteristic's value handle.
596  * The value will be returned in several blobs.
597  * For each blob, a GATT_EVENT_LONG_CHARACTERISTIC_VALUE_QUERY_RESULT event with updated value offset will be emitted.
598  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
599  * @param  callback
600  * @param  con_handle
601  * @param  value_handle
602  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
603  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
604  *                ERROR_CODE_SUCCESS         , if query is successfully registered
605  */
606 uint8_t gatt_client_read_long_value_of_characteristic_using_value_handle(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle);
607 
608 /**
609  * @brief Reads the long characteristic value using the characteristic's value handle.
610  * The value will be returned in several blobs.
611  * For each blob, a GATT_EVENT_LONG_CHARACTERISTIC_VALUE_QUERY_RESULT event with updated value offset will be emitted.
612  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
613  * @param  callback
614  * @param  con_handle
615  * @param  value_handle
616  * @param  offset
617  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
618  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
619  *                ERROR_CODE_SUCCESS         , if query is successfully registered
620  */
621 uint8_t gatt_client_read_long_value_of_characteristic_using_value_handle_with_offset(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle, uint16_t offset);
622 
623 /*
624  * @brief Read multiple characteristic values.
625  * The all results are emitted via single GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT event,
626  * followed by the GATT_EVENT_QUERY_COMPLETE event, which marks the end of read.
627  * @param  callback
628  * @param  con_handle
629  * @param  num_value_handles
630  * @param  value_handles list of handles
631  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
632  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
633  *                ERROR_CODE_SUCCESS         , if query is successfully registered
634  */
635 uint8_t gatt_client_read_multiple_characteristic_values(btstack_packet_handler_t callback, hci_con_handle_t con_handle, int num_value_handles, uint16_t * value_handles);
636 
637 /*
638  * @brief Read multiple varaible characteristic values. Only supported over LE Enhanced Bearer
639  * The all results are emitted via single GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT event,
640  * followed by the GATT_EVENT_QUERY_COMPLETE event, which marks the end of read.
641  * @param  callback
642  * @param  con_handle
643  * @param  num_value_handles
644  * @param  value_handles list of handles
645  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
646  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
647  *                ERROR_CODE_SUCCESS         , if query is successfully registered
648  */
649 uint8_t gatt_client_read_multiple_variable_characteristic_values(btstack_packet_handler_t callback, hci_con_handle_t con_handle, int num_value_handles, uint16_t * value_handles);
650 
651 /**
652  * @brief Writes the characteristic value using the characteristic's value handle without
653  * an acknowledgment that the write was successfully performed.
654  * @param  con_handle
655  * @param  value_handle
656  * @param  value_length
657  * @param  value is copied on success and does not need to be retained
658  * @return status BTSTACK_MEMORY_ALLOC_FAILED, if no GATT client for con_handle is found
659  *                GATT_CLIENT_IN_WRONG_STATE , if GATT client is not ready
660  *                BTSTACK_ACL_BUFFERS_FULL   , if L2CAP cannot send, there are no free ACL slots
661  *                ERROR_CODE_SUCCESS         , if query is successfully registered
662  */
663 uint8_t gatt_client_write_value_of_characteristic_without_response(hci_con_handle_t con_handle, uint16_t value_handle, uint16_t value_length, uint8_t * value);
664 
665 /**
666  * @brief Writes the authenticated characteristic value using the characteristic's value handle
667  * without an acknowledgment that the write was successfully performed.
668  * @note GATT_EVENT_QUERY_COMPLETE is emitted with ATT_ERROR_SUCCESS for success,
669  * or ATT_ERROR_BONDING_INFORMATION_MISSING if there is no bonding information stored.
670  * @param  callback
671  * @param  con_handle
672  * @param  value_handle
673  * @param  message_len
674  * @param  message is not copied, make sure memory is accessible until write is done
675  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
676  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
677  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
678  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
679  */
680 uint8_t gatt_client_signed_write_without_response(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle, uint16_t message_len, uint8_t * message);
681 
682 /**
683  * @brief Writes the characteristic value using the characteristic's value handle.
684  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
685  * The write is successfully performed, if the event's att_status field is set to
686  * ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
687  * @param  callback
688  * @param  con_handle
689  * @param  value_handle
690  * @param  value_length
691  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
692  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
693  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
694  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
695  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
696  */
697 uint8_t gatt_client_write_value_of_characteristic(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle, uint16_t value_length, uint8_t * value);
698 
699 /**
700  * @brief Writes the characteristic value using the characteristic's value handle.
701  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
702  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
703  * @param  callback
704  * @param  con_handle
705  * @param  value_handle
706  * @param  value_length
707  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
708  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
709  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
710  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
711  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
712  */
713 uint8_t gatt_client_write_long_value_of_characteristic(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle, uint16_t value_length, uint8_t * value);
714 
715 /**
716  * @brief Writes the characteristic value using the characteristic's value handle.
717  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
718  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
719  * @param  callback
720  * @param  con_handle
721  * @param  value_handle
722  * @param  offset of value
723  * @param  value_length
724  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
725  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
726  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
727  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
728  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
729  */
730 uint8_t gatt_client_write_long_value_of_characteristic_with_offset(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle, uint16_t offset, uint16_t value_length, uint8_t * value);
731 
732 /**
733  * @brief Writes of the long characteristic value using the characteristic's value handle.
734  * It uses server response to validate that the write was correctly received.
735  * The GATT_EVENT_QUERY_COMPLETE EVENT marks the end of write.
736  * The write is successfully performed, if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
737  * @param  callback
738  * @param  con_handle
739  * @param  value_handle
740  * @param  value_length
741  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
742  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
743  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
744  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
745  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
746  */
747 uint8_t gatt_client_reliable_write_long_value_of_characteristic(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t value_handle, uint16_t value_length, uint8_t * value);
748 
749 /**
750  * @brief Reads the characteristic descriptor using its handle.
751  * If the characteristic descriptor is found, a GATT_EVENT_CHARACTERISTIC_DESCRIPTOR_QUERY_RESULT event will be emitted.
752  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
753  * @param  callback
754  * @param  con_handle
755  * @param  descriptor
756  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
757  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
758  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
759  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
760  */
761 uint8_t gatt_client_read_characteristic_descriptor(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_descriptor_t * descriptor);
762 
763 /**
764  * @brief Reads the characteristic descriptor using its handle.
765  * If the characteristic descriptor is found, a GATT_EVENT_CHARACTERISTIC_DESCRIPTOR_QUERY_RESULT event will be emitted.
766  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
767  * @param  callback
768  * @param  con_handle
769  * @param  descriptor
770  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
771  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
772  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
773  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
774  */
775 uint8_t gatt_client_read_characteristic_descriptor_using_descriptor_handle(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t descriptor_handle);
776 
777 /**
778  * @brief Reads the long characteristic descriptor using its handle. It will be returned in several blobs.
779  * For each blob, a GATT_EVENT_CHARACTERISTIC_DESCRIPTOR_QUERY_RESULT event will be emitted.
780  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
781  * @param  callback
782  * @param  con_handle
783  * @param  descriptor
784  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
785  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
786  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
787  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
788  */
789 uint8_t gatt_client_read_long_characteristic_descriptor(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_descriptor_t * descriptor);
790 
791 /**
792  * @brief Reads the long characteristic descriptor using its handle. It will be returned in several blobs.
793  * For each blob, a GATT_EVENT_CHARACTERISTIC_DESCRIPTOR_QUERY_RESULT event will be emitted.
794  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
795  * @param  callback
796  * @param  con_handle
797  * @param  descriptor_handle
798  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
799  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
800  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
801  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
802  */
803 uint8_t gatt_client_read_long_characteristic_descriptor_using_descriptor_handle(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t descriptor_handle);
804 
805 /**
806  * @brief Reads the long characteristic descriptor using its handle. It will be returned in several blobs.
807  * For each blob, a GATT_EVENT_CHARACTERISTIC_DESCRIPTOR_QUERY_RESULT event will be emitted.
808  * The GATT_EVENT_QUERY_COMPLETE event marks the end of read.
809  * @param  callback
810  * @param  con_handle
811  * @param  descriptor_handle
812  * @param  offset
813  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
814  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
815  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
816  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
817  */
818 uint8_t gatt_client_read_long_characteristic_descriptor_using_descriptor_handle_with_offset(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t descriptor_handle, uint16_t offset);
819 
820 /**
821  * @brief Writes the characteristic descriptor using its handle.
822  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
823  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
824  * @param  callback
825  * @param  con_handle
826  * @param  descriptor
827  * @param  value_length
828  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
829  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
830  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
831  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
832  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
833  */
834 uint8_t gatt_client_write_characteristic_descriptor(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_descriptor_t * descriptor, uint16_t value_length, uint8_t * value);
835 
836 /**
837  * @brief Writes the characteristic descriptor using its handle.
838  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
839  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
840  * @param  callback
841  * @param  con_handle
842  * @param  descriptor_handle
843  * @param  value_length
844  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
845  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
846  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
847  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
848  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
849  */
850 uint8_t gatt_client_write_characteristic_descriptor_using_descriptor_handle(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t descriptor_handle, uint16_t value_length, uint8_t * value);
851 
852 /**
853  * @brief Writes the characteristic descriptor using its handle.
854  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
855  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
856  * @param  callback
857  * @param  con_handle
858  * @param  descriptor
859  * @param  value_length
860  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
861  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
862  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
863  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
864  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
865  */
866 uint8_t gatt_client_write_long_characteristic_descriptor(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_descriptor_t * descriptor, uint16_t value_length, uint8_t * value);
867 
868 /**
869  * @brief Writes the characteristic descriptor using its handle.
870  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
871  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
872  * @param  callback
873  * @param  con_handle
874  * @param  descriptor_handle
875  * @param  value_length
876  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
877  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
878  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
879  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
880  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
881  */
882 uint8_t gatt_client_write_long_characteristic_descriptor_using_descriptor_handle(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t descriptor_handle, uint16_t value_length, uint8_t * value);
883 
884 /**
885  * @brief Writes the characteristic descriptor using its handle.
886  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
887  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
888  * @param  callback
889  * @param  con_handle
890  * @param  descriptor_handle
891  * @param  offset of value
892  * @param  value_length
893  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
894  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
895  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
896  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
897  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
898  */
899 uint8_t gatt_client_write_long_characteristic_descriptor_using_descriptor_handle_with_offset(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t descriptor_handle, uint16_t offset, uint16_t value_length, uint8_t * value);
900 
901 /**
902  * @brief Writes the client characteristic configuration of the specified characteristic.
903  * It is used to subscribe for notifications or indications of the characteristic value.
904  * For notifications or indications specify: GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION
905  * resp. GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_INDICATION as configuration value.
906  * The GATT_EVENT_QUERY_COMPLETE event marks the end of write.
907  * The write is successfully performed if the event's att_status field is set to ATT_ERROR_SUCCESS (see bluetooth.h for ATT_ERROR codes).
908  * @param  callback
909  * @param  con_handle
910  * @param  characteristic
911  * @param  configuration                                                    GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_INDICATION
912  * @return status ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER                  if no HCI connection for con_handle is found
913  *                BTSTACK_MEMORY_ALLOC_FAILED                               if no GATT client for con_handle could be allocated
914  *                GATT_CLIENT_IN_WRONG_STATE                                if GATT client is not ready
915  *                GATT_CLIENT_CHARACTERISTIC_NOTIFICATION_NOT_SUPPORTED     if configuring notification, but characteristic has no notification property set
916  *                GATT_CLIENT_CHARACTERISTIC_INDICATION_NOT_SUPPORTED       if configuring indication, but characteristic has no indication property set
917  *                ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE         if configuration is invalid
918  *                ERROR_CODE_SUCCESS                                        if query is successfully registered
919  */
920 uint8_t gatt_client_write_client_characteristic_configuration(btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_t * characteristic, uint16_t configuration);
921 
922 /**
923  * @brief Register for notifications and indications of a characteristic enabled by
924  * the gatt_client_write_client_characteristic_configuration function.
925  * @param notification struct used to store registration
926  * @param callback
927  * @param con_handle or GATT_CLIENT_ANY_CONNECTION to receive updates from all connected devices
928  * @param characteristic or NULL to receive updates for all characteristics
929  */
930 void gatt_client_listen_for_characteristic_value_updates(gatt_client_notification_t * notification, btstack_packet_handler_t callback, hci_con_handle_t con_handle, gatt_client_characteristic_t * characteristic);
931 
932 /**
933  * @brief Stop listening to characteristic value updates registered with
934  * the gatt_client_listen_for_characteristic_value_updates function.
935  * @param notification struct used in gatt_client_listen_for_characteristic_value_updates
936  */
937 void gatt_client_stop_listening_for_characteristic_value_updates(gatt_client_notification_t * notification);
938 
939 /**
940  * @brief Transactional write. It can be called as many times as it is needed to write the characteristics within the same transaction.
941  * Call the gatt_client_execute_write function to commit the transaction.
942  * @param  callback
943  * @param  con_handle
944  * @param  attribute_handle
945  * @param  offset of value
946  * @param  value_length
947  * @param  value is not copied, make sure memory is accessible until write is done, i.e. GATT_EVENT_QUERY_COMPLETE is received
948  */
949 uint8_t gatt_client_prepare_write(btstack_packet_handler_t callback, hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t offset, uint16_t value_length, uint8_t * value);
950 
951 /**
952  * @brief Commit transactional write. GATT_EVENT_QUERY_COMPLETE is received.
953  * @param  callback
954  * @param  con_handle
955  * @return status
956  */
957 uint8_t gatt_client_execute_write(btstack_packet_handler_t callback, hci_con_handle_t con_handle);
958 
959 /**
960  * @brief Abort transactional write. GATT_EVENT_QUERY_COMPLETE is received.
961  * @param  callback
962  * @param  con_handle
963  * @return status
964  */
965 uint8_t gatt_client_cancel_write(btstack_packet_handler_t callback, hci_con_handle_t con_handle);
966 
967 /**
968  * @brief Request callback when regular gatt query can be sent
969  * @note callback might happen during call to this function
970  * @param callback_registration to point to callback function and context information
971  * @param con_handle
972  * @return ERROR_CODE_SUCCESS if ok, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER if handle unknown, and ERROR_CODE_COMMAND_DISALLOWED if callback already registered
973  */
974 uint8_t gatt_client_request_to_send_gatt_query(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle);
975 
976 /**
977  * @brief Request callback when writing characteristic value without response is possible
978  * @note callback might happen during call to this function
979  * @param callback_registration to point to callback function and context information
980  * @param con_handle
981  * @return ERROR_CODE_SUCCESS if ok, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER if handle unknown, and ERROR_CODE_COMMAND_DISALLOWED if callback already registered
982  */
983 uint8_t gatt_client_request_to_write_without_response(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle);
984 
985 
986 // the following functions are marked as deprecated and will be removed eventually
987 /**
988  * @brief Requests GATT_EVENT_CAN_WRITE_WITHOUT_RESPONSE that guarantees
989  * a single successful gatt_client_write_value_of_characteristic_without_response call.
990  * @deprecated please use gatt_client_request_to_write_without_response instead
991  * @param  callback
992  * @param  con_handle
993  * @return status
994  */
995 uint8_t gatt_client_request_can_write_without_response_event(btstack_packet_handler_t callback, hci_con_handle_t con_handle);
996 
997 
998 /* API_END */
999 
1000 // used by generated btstack_event.c
1001 
1002 void gatt_client_deserialize_service(const uint8_t *packet, int offset, gatt_client_service_t * service);
1003 void gatt_client_deserialize_characteristic(const uint8_t * packet, int offset, gatt_client_characteristic_t * characteristic);
1004 void gatt_client_deserialize_characteristic_descriptor(const uint8_t * packet, int offset, gatt_client_characteristic_descriptor_t * descriptor);
1005 
1006 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
1007 void gatt_client_att_packet_handler_fuzz(uint8_t packet_type, uint16_t handle, uint8_t *packet, uint16_t size);
1008 uint8_t gatt_client_get_client(hci_con_handle_t con_handle, gatt_client_t ** gatt_client);
1009 #endif
1010 
1011 #if defined __cplusplus
1012 }
1013 #endif
1014 
1015 #endif
1016