xref: /btstack/src/ble/att_server.h (revision 25d5427a345779b159b63c0d8b197d2dee40cf37)
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 /**
39  * @title ATT Server
40  *
41  */
42 
43 #ifndef ATT_SERVER_H
44 #define ATT_SERVER_H
45 
46 #include <stdint.h>
47 #include "hci.h"
48 #include "ble/att_db.h"
49 #include "btstack_defines.h"
50 #include "btstack_config.h"
51 
52 #if defined __cplusplus
53 extern "C" {
54 #endif
55 
56 #ifdef ENABLE_GATT_OVER_EATT
57 typedef struct {
58     btstack_linked_item_t item;
59     att_server_t     att_server;
60     att_connection_t att_connection;
61     uint8_t * receive_buffer;
62     uint8_t * send_buffer;
63 } att_server_eatt_bearer_t;
64 #endif
65 
66 /* API_START */
67 /*
68  * @brief setup ATT server
69  * @param db attribute database created by compile-gatt.py
70  * @param read_callback, see att_db.h, can be NULL
71  * @param write_callback, see attl.h, can be NULL
72  */
73 void att_server_init(uint8_t const * db, att_read_callback_t read_callback, att_write_callback_t write_callback);
74 
75 /**
76  * @brief Enable support for Enhanced ATT bearer
77  * @note Requires ENABLE_GATT_OVER_EATT
78  * @param num_eatt_bearers
79  * @param storage_buffer
80  * @param storage_size must be >= num_eatt_bearers * sizeof(att_server_eatt_bearer_t)
81  * @return status   ERROR_CODE_SUCCESS
82  *                  ERROR_CODE_MEMORY_CAPACITY_EXCEEDED if buffer too small or no entry in l2cap service pool
83  *                  L2CAP_SERVICE_ALREADY_REGISTERED if called twice
84  */
85 uint8_t att_server_eatt_init(uint8_t num_eatt_bearers, uint8_t * storage_buffer, uint16_t storage_size);
86 
87 /*
88  * @brief register packet handler for ATT server events:
89  *        - ATT_EVENT_CAN_SEND_NOW
90  *        - ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE
91  *        - ATT_EVENT_MTU_EXCHANGE_COMPLETE
92  * @param handler
93  */
94 void att_server_register_packet_handler(btstack_packet_handler_t handler);
95 
96 /**
97  * @brief register read/write callbacks for specific handle range
98  * @param att_service_handler_t
99  */
100 void att_server_register_service_handler(att_service_handler_t * handler);
101 
102 /**
103  * @brief Request callback when sending is possible
104  * @note callback might happend during call to this function
105  * @param callback_registration to point to callback function and context information
106  * @param con_handle
107  * @return 0 if ok, error otherwise
108  */
109 uint8_t att_server_register_can_send_now_callback(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle);
110 
111 /**
112  * @brief Return ATT MTU
113  * @param con_handle
114  * @return mtu if ok, 0 otherwise
115  */
116 uint16_t att_server_get_mtu(hci_con_handle_t con_handle);
117 
118 /**
119  * @brief Request callback when sending notifcation is possible
120  * @note callback might happend during call to this function
121  * @param callback_registration to point to callback function and context information
122  * @param con_handle
123  * @return ERROR_CODE_SUCCESS if ok, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER if handle unknown, and ERROR_CODE_COMMAND_DISALLOWED if callback already registered
124  */
125 uint8_t att_server_request_to_send_notification(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle);
126 
127 /**
128  * @brief Request callback when sending indication is possible
129  * @note callback might happend during call to this function
130  * @param callback_registration to point to callback function and context information
131  * @param con_handle
132  * @return ERROR_CODE_SUCCESS if ok, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER if handle unknown, and ERROR_CODE_COMMAND_DISALLOWED if callback already registered
133  */
134 uint8_t att_server_request_to_send_indication(btstack_context_callback_registration_t * callback_registration, hci_con_handle_t con_handle);
135 
136 /**
137  * @brief notify client about attribute value change
138  * @param con_handle
139  * @param attribute_handle
140  * @param value
141  * @param value_len
142  * @return 0 if ok, error otherwise
143  */
144 uint8_t att_server_notify(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len);
145 
146 /**
147  * @brief notify client about multiple attribute value changes
148  * @param con_handle
149  * @param num_attributes
150  * @param attribute_handles[]
151  * @param values_data[]
152  * @param values_len[]
153  * @return 0 if ok, error otherwise
154  */
155 uint8_t att_server_multiple_notify(hci_con_handle_t con_handle, uint8_t num_attributes,
156                                    const uint16_t * attribute_handles, const uint8_t ** values_data, const uint16_t * values_len);
157 
158 /**
159  * @brief indicate value change to client. client is supposed to reply with an indication_response
160  * @param con_handle
161  * @param attribute_handle
162  * @param value
163  * @param value_len
164  * @return 0 if ok, error otherwise
165  */
166 uint8_t att_server_indicate(hci_con_handle_t con_handle, uint16_t attribute_handle, const uint8_t *value, uint16_t value_len);
167 
168 #ifdef ENABLE_ATT_DELAYED_RESPONSE
169 /**
170  * @brief response ready - called after returning ATT_READ__RESPONSE_PENDING in an att_read_callback or
171  * ATT_ERROR_WRITE_REQUEST_PENDING IN att_write_callback before to trigger callback again and complete the transaction
172  * @nore The ATT Server will retry handling the current ATT request
173  * @param con_handle
174  * @return 0 if ok, error otherwise
175  */
176 uint8_t att_server_response_ready(hci_con_handle_t con_handle);
177 #endif
178 
179 /**
180  * De-Init ATT Server
181  */
182 void att_server_deinit(void);
183 
184 // the following functions will be removed soon
185 
186 /**
187  * @brief tests if a notification or indication can be send right now
188  * @param con_handle
189  * @return 1, if packet can be sent
190  */
191 int  att_server_can_send_packet_now(hci_con_handle_t con_handle);
192 
193 /**
194  * @brief Request emission of ATT_EVENT_CAN_SEND_NOW as soon as possible
195  * @note ATT_EVENT_CAN_SEND_NOW might be emitted during call to this function
196  *       so packet handler should be ready to handle it
197  * @param con_handle
198  */
199 void att_server_request_can_send_now_event(hci_con_handle_t con_handle);
200 // end of deprecated functions
201 
202 /* API_END */
203 
204 #if defined __cplusplus
205 }
206 #endif
207 
208 #endif // ATT_SERVER_H
209