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 <base/logging.h>
32 #include <string.h>
33 
34 #include "bt_common.h"
35 #include "btif_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     CHECK(connect_queue != NULL);
72   }
73 
74   // Sanity check to make sure we're not leaking connection requests
75   CHECK(list_length(connect_queue) < MAX_REASONABLE_REQUESTS);
76 
77   for (const list_node_t* node = list_begin(connect_queue);
78        node != list_end(connect_queue); node = list_next(node)) {
79     if (((connect_node_t*)list_node(node))->uuid == p_param->uuid) {
80       LOG_INFO(LOG_TAG, "%s dropping duplicate connect request for uuid: %04x",
81                __func__, p_param->uuid);
82       return;
83     }
84   }
85 
86   connect_node_t* p_node = (connect_node_t*)osi_malloc(sizeof(connect_node_t));
87   memcpy(p_node, p_param, sizeof(connect_node_t));
88   list_append(connect_queue, p_node);
89 }
90 
queue_int_advance()91 static void queue_int_advance() {
92   if (connect_queue && !list_is_empty(connect_queue))
93     list_remove(connect_queue, list_front(connect_queue));
94 }
95 
queue_int_handle_evt(uint16_t event,char * p_param)96 static void queue_int_handle_evt(uint16_t event, char* p_param) {
97   switch (event) {
98     case BTIF_QUEUE_CONNECT_EVT:
99       queue_int_add((connect_node_t*)p_param);
100       break;
101 
102     case BTIF_QUEUE_ADVANCE_EVT:
103       queue_int_advance();
104       break;
105   }
106 
107   if (stack_manager_get_interface()->get_stack_is_running())
108     btif_queue_connect_next();
109 }
110 
111 /*******************************************************************************
112  *
113  * Function         btif_queue_connect
114  *
115  * Description      Add a new connection to the queue and trigger the next
116  *                  scheduled connection.
117  *
118  * Returns          BT_STATUS_SUCCESS if successful
119  *
120  ******************************************************************************/
btif_queue_connect(uint16_t uuid,const bt_bdaddr_t * bda,btif_connect_cb_t connect_cb)121 bt_status_t btif_queue_connect(uint16_t uuid, const bt_bdaddr_t* bda,
122                                btif_connect_cb_t connect_cb) {
123   connect_node_t node;
124   memset(&node, 0, sizeof(connect_node_t));
125   memcpy(&node.bda, bda, sizeof(bt_bdaddr_t));
126   node.uuid = uuid;
127   node.connect_cb = connect_cb;
128 
129   return btif_transfer_context(queue_int_handle_evt, BTIF_QUEUE_CONNECT_EVT,
130                                (char*)&node, sizeof(connect_node_t), NULL);
131 }
132 
133 /*******************************************************************************
134  *
135  * Function         btif_queue_advance
136  *
137  * Description      Clear the queue's busy status and advance to the next
138  *                  scheduled connection.
139  *
140  * Returns          void
141  *
142  ******************************************************************************/
btif_queue_advance()143 void btif_queue_advance() {
144   btif_transfer_context(queue_int_handle_evt, BTIF_QUEUE_ADVANCE_EVT, NULL, 0,
145                         NULL);
146 }
147 
148 // This function dispatches the next pending connect request. It is called from
149 // stack_manager when the stack comes up.
btif_queue_connect_next(void)150 bt_status_t btif_queue_connect_next(void) {
151   if (!connect_queue || list_is_empty(connect_queue)) return BT_STATUS_FAIL;
152 
153   connect_node_t* p_head = (connect_node_t*)list_front(connect_queue);
154 
155   // If the queue is currently busy, we return success anyway,
156   // since the connection has been queued...
157   if (p_head->busy) return BT_STATUS_SUCCESS;
158 
159   p_head->busy = true;
160   return p_head->connect_cb(&p_head->bda, p_head->uuid);
161 }
162 
163 /*******************************************************************************
164  *
165  * Function         btif_queue_release
166  *
167  * Description      Free up all the queue nodes and set the queue head to NULL
168  *
169  * Returns          void
170  *
171  ******************************************************************************/
btif_queue_release()172 void btif_queue_release() {
173   list_free(connect_queue);
174   connect_queue = NULL;
175 }
176