1 /******************************************************************************
2  *
3  *  Copyright (C) 2009-2012 Broadcom Corporation
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at:
8  *
9  *  http://www.apache.org/licenses/LICENSE-2.0
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  ******************************************************************************/
18 
19 /*******************************************************************************
20  *
21  *  Filename:      btif_profile_queue.c
22  *
23  *  Description:   Bluetooth remote device connection queuing implementation.
24  *
25  ******************************************************************************/
26 
27 #define LOG_TAG "bt_btif_queue"
28 
29 #include "btif_profile_queue.h"
30 
31 #include <assert.h>
32 #include <string.h>
33 
34 #include "btif_common.h"
35 #include "bt_common.h"
36 #include "osi/include/allocator.h"
37 #include "osi/include/list.h"
38 #include "stack_manager.h"
39 
40 /*******************************************************************************
41 **  Local type definitions
42 *******************************************************************************/
43 
44 typedef enum {
45   BTIF_QUEUE_CONNECT_EVT,
46   BTIF_QUEUE_ADVANCE_EVT,
47 } btif_queue_event_t;
48 
49 typedef struct {
50     bt_bdaddr_t bda;
51     uint16_t uuid;
52     bool busy;
53     btif_connect_cb_t connect_cb;
54 } connect_node_t;
55 
56 /*******************************************************************************
57 **  Static variables
58 *******************************************************************************/
59 
60 static list_t *connect_queue;
61 
62 static const size_t MAX_REASONABLE_REQUESTS = 10;
63 
64 /*******************************************************************************
65 **  Queue helper functions
66 *******************************************************************************/
67 
queue_int_add(connect_node_t * p_param)68 static void queue_int_add(connect_node_t *p_param) {
69     if (!connect_queue) {
70         connect_queue = list_new(osi_free);
71         assert(connect_queue != NULL);
72     }
73 
74     // Sanity check to make sure we're not leaking connection requests
75     assert(list_length(connect_queue) < MAX_REASONABLE_REQUESTS);
76 
77     for (const list_node_t *node = list_begin(connect_queue); node != list_end(connect_queue); node = list_next(node)) {
78         if (((connect_node_t *)list_node(node))->uuid == p_param->uuid) {
79             LOG_INFO(LOG_TAG, "%s dropping duplicate connect request for uuid: %04x", __func__, p_param->uuid);
80             return;
81         }
82     }
83 
84     connect_node_t *p_node = osi_malloc(sizeof(connect_node_t));
85     memcpy(p_node, p_param, sizeof(connect_node_t));
86     list_append(connect_queue, p_node);
87 }
88 
queue_int_advance()89 static void queue_int_advance() {
90     if (connect_queue && !list_is_empty(connect_queue))
91         list_remove(connect_queue, list_front(connect_queue));
92 }
93 
queue_int_handle_evt(UINT16 event,char * p_param)94 static void queue_int_handle_evt(UINT16 event, char *p_param) {
95     switch(event) {
96         case BTIF_QUEUE_CONNECT_EVT:
97             queue_int_add((connect_node_t *)p_param);
98             break;
99 
100         case BTIF_QUEUE_ADVANCE_EVT:
101             queue_int_advance();
102             break;
103     }
104 
105     if (stack_manager_get_interface()->get_stack_is_running())
106         btif_queue_connect_next();
107 }
108 
109 /*******************************************************************************
110 **
111 ** Function         btif_queue_connect
112 **
113 ** Description      Add a new connection to the queue and trigger the next
114 **                  scheduled connection.
115 **
116 ** Returns          BT_STATUS_SUCCESS if successful
117 **
118 *******************************************************************************/
btif_queue_connect(uint16_t uuid,const bt_bdaddr_t * bda,btif_connect_cb_t connect_cb)119 bt_status_t btif_queue_connect(uint16_t uuid, const bt_bdaddr_t *bda, btif_connect_cb_t connect_cb) {
120     connect_node_t node;
121     memset(&node, 0, sizeof(connect_node_t));
122     memcpy(&node.bda, bda, sizeof(bt_bdaddr_t));
123     node.uuid = uuid;
124     node.connect_cb = connect_cb;
125 
126     return btif_transfer_context(queue_int_handle_evt, BTIF_QUEUE_CONNECT_EVT,
127                           (char *)&node, sizeof(connect_node_t), NULL);
128 }
129 
130 /*******************************************************************************
131 **
132 ** Function         btif_queue_advance
133 **
134 ** Description      Clear the queue's busy status and advance to the next
135 **                  scheduled connection.
136 **
137 ** Returns          void
138 **
139 *******************************************************************************/
btif_queue_advance()140 void btif_queue_advance() {
141     btif_transfer_context(queue_int_handle_evt, BTIF_QUEUE_ADVANCE_EVT,
142                           NULL, 0, NULL);
143 }
144 
145 // This function dispatches the next pending connect request. It is called from
146 // stack_manager when the stack comes up.
btif_queue_connect_next(void)147 bt_status_t btif_queue_connect_next(void) {
148     if (!connect_queue || list_is_empty(connect_queue))
149         return BT_STATUS_FAIL;
150 
151     connect_node_t *p_head = list_front(connect_queue);
152 
153     // If the queue is currently busy, we return success anyway,
154     // since the connection has been queued...
155     if (p_head->busy)
156         return BT_STATUS_SUCCESS;
157 
158     p_head->busy = true;
159     return p_head->connect_cb(&p_head->bda, p_head->uuid);
160 }
161 
162 /*******************************************************************************
163 **
164 ** Function         btif_queue_release
165 **
166 ** Description      Free up all the queue nodes and set the queue head to NULL
167 **
168 ** Returns          void
169 **
170 *******************************************************************************/
btif_queue_release()171 void btif_queue_release() {
172     list_free(connect_queue);
173     connect_queue = NULL;
174 }
175