xref: /btstack/src/ble/att_dispatch.c (revision ca7f8243b0d02a799100889530c5b9f4dbde3709)
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  * Dispatcher for independent implementation of ATT client and server
41  */
42 
43 #include "l2cap.h"
44 
45 #include "att_dispatch.h"
46 #include "btstack_debug.h"
47 
48 static void dummy_packet_handler(uint8_t packet_type, uint16_t handle, uint8_t *packet, uint16_t size);
49 
50 static btstack_packet_handler_t att_client_handler = &dummy_packet_handler;
51 static btstack_packet_handler_t att_server_handler = &dummy_packet_handler;
52 
53 static btstack_packet_callback_registration_t hci_event_callback_registration;
54 
55 static int registered_for_hci_events = 0;
56 
57 static void dummy_packet_handler(uint8_t packet_type, uint16_t handle, uint8_t *packet, uint16_t size){
58 }
59 
60 static void att_hci_event_handler(uint8_t packet_type, uint8_t * packet, uint16_t size){
61 	att_client_handler(packet_type, 0, packet, size);
62 	att_server_handler(packet_type, 0, packet, size);
63 }
64 
65 static void att_dispatch_register_for_hci_events(void){
66 	if (registered_for_hci_events) return;
67 	registered_for_hci_events = 1;
68     hci_event_callback_registration.callback = &att_hci_event_handler;
69     hci_add_event_handler(&hci_event_callback_registration);
70 }
71 
72 static void att_packet_handler(uint8_t packet_type, uint16_t handle, uint8_t *packet, uint16_t size){
73 	if (packet_type != ATT_DATA_PACKET) return;
74 
75 	// log_info("att_data_packet with opcode 0x%x", packet[0]);
76 	uint8_t att_pdu_odd = packet[0] & 1;
77 	if (att_pdu_odd){
78 		// odd PDUs are sent from server to client
79 		att_client_handler(packet_type, handle, packet, size);
80 	} else {
81 		// even PDUs are sent from client to server
82 		att_server_handler(packet_type, handle, packet, size);
83 	}
84 }
85 
86 /**
87  * @brief reset att dispatchter
88  * @param packet_hander for ATT client packets
89  */
90 void att_dispatch_register_client(btstack_packet_handler_t packet_handler){
91 	att_dispatch_register_for_hci_events();
92 	if (packet_handler == NULL){
93 		packet_handler = dummy_packet_handler;
94 	}
95 	att_client_handler = packet_handler;
96 	l2cap_register_fixed_channel(att_packet_handler, L2CAP_CID_ATTRIBUTE_PROTOCOL);
97 }
98 
99 /**
100  * @brief reset att dispatchter
101  * @param packet_hander for ATT server packets
102  */
103 void att_dispatch_register_server(btstack_packet_handler_t packet_handler){
104 	att_dispatch_register_for_hci_events();
105 	if (packet_handler == NULL){
106 		packet_handler = dummy_packet_handler;
107 	}
108 	att_server_handler = packet_handler;
109 	l2cap_register_fixed_channel(att_packet_handler, L2CAP_CID_ATTRIBUTE_PROTOCOL);
110 }
111