1 /*
2 * Copyright 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 /*******************************************************************************
18 *
19 * Filename: btif_uid.cc
20 *
21 * Description: Contains data structures and functions for keeping track of
22 * socket usage per app UID.
23 *
24 ******************************************************************************/
25 #include <mutex>
26
27 #include "bt_common.h"
28 #include "btif_uid.h"
29
30 static std::mutex set_lock;
31
32 typedef struct uid_set_node_t {
33 struct uid_set_node_t* next;
34 bt_uid_traffic_t data;
35 } uid_set_node_t;
36
37 typedef struct uid_set_t {
38 uid_set_node_t* head;
39 } uid_set_t;
40
uid_set_create(void)41 uid_set_t* uid_set_create(void) {
42 uid_set_t* set = (uid_set_t*)osi_calloc(sizeof(uid_set_t));
43 return set;
44 }
45
uid_set_destroy(uid_set_t * set)46 void uid_set_destroy(uid_set_t* set) {
47 std::unique_lock<std::mutex> guard(set_lock);
48 uid_set_node_t* node = set->head;
49 while (node) {
50 uid_set_node_t* temp = node;
51 node = node->next;
52 osi_free(temp);
53 }
54 set->head = NULL;
55 osi_free(set);
56 }
57
58 // Lock in uid_set_t must be held.
uid_set_find_or_create_node(uid_set_t * set,int32_t app_uid)59 static uid_set_node_t* uid_set_find_or_create_node(uid_set_t* set,
60 int32_t app_uid) {
61 uid_set_node_t* node = set->head;
62 while (node && node->data.app_uid != app_uid) {
63 node = node->next;
64 }
65
66 if (!node) {
67 node = (uid_set_node_t*)osi_calloc(sizeof(uid_set_node_t));
68 node->data.app_uid = app_uid;
69 node->next = set->head;
70 set->head = node;
71 }
72 return node;
73 }
74
uid_set_add_tx(uid_set_t * set,int32_t app_uid,uint64_t bytes)75 void uid_set_add_tx(uid_set_t* set, int32_t app_uid, uint64_t bytes) {
76 if (app_uid == -1 || bytes == 0) return;
77
78 std::unique_lock<std::mutex> guard(set_lock);
79 uid_set_node_t* node = uid_set_find_or_create_node(set, app_uid);
80 node->data.tx_bytes += bytes;
81 }
82
uid_set_add_rx(uid_set_t * set,int32_t app_uid,uint64_t bytes)83 void uid_set_add_rx(uid_set_t* set, int32_t app_uid, uint64_t bytes) {
84 if (app_uid == -1 || bytes == 0) return;
85
86 std::unique_lock<std::mutex> guard(set_lock);
87 uid_set_node_t* node = uid_set_find_or_create_node(set, app_uid);
88 node->data.rx_bytes += bytes;
89 }
90
uid_set_read_and_clear(uid_set_t * set)91 bt_uid_traffic_t* uid_set_read_and_clear(uid_set_t* set) {
92 std::unique_lock<std::mutex> guard(set_lock);
93
94 // Find the length
95 size_t len = 0;
96 uid_set_node_t* node = set->head;
97 while (node) {
98 len++;
99 node = node->next;
100 }
101
102 // Allocate an array of elements + 1, to signify the end with app_uid set to
103 // -1.
104 bt_uid_traffic_t* result =
105 (bt_uid_traffic_t*)osi_calloc(sizeof(bt_uid_traffic_t) * (len + 1));
106
107 bt_uid_traffic_t* data = result;
108 node = set->head;
109 while (node) {
110 // Copy the data.
111 *data = node->data;
112 data++;
113
114 // Clear the counters.
115 node->data.rx_bytes = 0;
116 node->data.tx_bytes = 0;
117 node = node->next;
118 }
119
120 // Mark the last entry
121 data->app_uid = -1;
122
123 return result;
124 }
125