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 * 22 * Filename: btif_sm.c 23 * 24 * Description: Generic BTIF state machine API 25 * 26 *****************************************************************************/ 27 #include <hardware/bluetooth.h> 28 29 #define LOG_TAG "BTIF_SM" 30 #include "btif_common.h" 31 #include "btif_sm.h" 32 #include "gki.h" 33 34 /***************************************************************************** 35 ** Constants & Macros 36 ******************************************************************************/ 37 38 39 /***************************************************************************** 40 ** Local type definitions 41 ******************************************************************************/ 42 typedef struct { 43 btif_sm_state_t state; 44 btif_sm_handler_t *p_handlers; 45 } btif_sm_cb_t; 46 47 /***************************************************************************** 48 ** Static variables 49 ******************************************************************************/ 50 51 /***************************************************************************** 52 ** Static functions 53 ******************************************************************************/ 54 55 /***************************************************************************** 56 ** Externs 57 ******************************************************************************/ 58 59 /***************************************************************************** 60 ** Functions 61 ******************************************************************************/ 62 63 /***************************************************************************** 64 ** 65 ** Function btif_sm_init 66 ** 67 ** Description Initializes the state machine with the state handlers 68 ** The caller should ensure that the table and the corresponding 69 ** states match. The location that 'p_handlers' points to shall 70 ** be available until the btif_sm_shutdown API is invoked. 71 ** 72 ** Returns Returns a pointer to the initialized state machine handle. 73 ** 74 ******************************************************************************/ 75 76 btif_sm_handle_t btif_sm_init(const btif_sm_handler_t *p_handlers, btif_sm_state_t initial_state) 77 { 78 btif_sm_cb_t *p_cb; 79 80 if (p_handlers == NULL) 81 { 82 BTIF_TRACE_ERROR1("%s : p_handlers is NULL", __FUNCTION__); 83 return NULL; 84 } 85 86 p_cb = (btif_sm_cb_t*) GKI_os_malloc(sizeof(btif_sm_cb_t)); 87 p_cb->state = initial_state; 88 p_cb->p_handlers = (btif_sm_handler_t*)p_handlers; 89 90 /* Send BTIF_SM_ENTER_EVT to the initial state */ 91 p_cb->p_handlers[initial_state](BTIF_SM_ENTER_EVT, NULL); 92 93 return (btif_sm_handle_t)p_cb; 94 } 95 96 /***************************************************************************** 97 ** 98 ** Function btif_sm_shutdown 99 ** 100 ** Description Tears down the state machine 101 ** 102 ** Returns None 103 ** 104 ******************************************************************************/ 105 void btif_sm_shutdown(btif_sm_handle_t handle) 106 { 107 btif_sm_cb_t *p_cb = (btif_sm_cb_t*)handle; 108 109 if (p_cb == NULL) 110 { 111 BTIF_TRACE_ERROR1("%s : Invalid handle", __FUNCTION__); 112 return; 113 } 114 GKI_os_free((void*)p_cb); 115 } 116 117 /***************************************************************************** 118 ** 119 ** Function btif_sm_get_state 120 ** 121 ** Description Fetches the current state of the state machine 122 ** 123 ** Returns Current state 124 ** 125 ******************************************************************************/ 126 btif_sm_state_t btif_sm_get_state(btif_sm_handle_t handle) 127 { 128 btif_sm_cb_t *p_cb = (btif_sm_cb_t*)handle; 129 130 if (p_cb == NULL) 131 { 132 BTIF_TRACE_ERROR1("%s : Invalid handle", __FUNCTION__); 133 return 0; 134 } 135 136 return p_cb->state; 137 } 138 139 /***************************************************************************** 140 ** 141 ** Function btif_sm_dispatch 142 ** 143 ** Description Dispatches the 'event' along with 'data' to the current state handler 144 ** 145 ** Returns BT_STATUS_SUCCESS on success 146 ** BT_STATUS_UNHANDLED if event was not processed 147 ** BT_STATUS_FAIL otherwise 148 ** 149 ******************************************************************************/ 150 bt_status_t btif_sm_dispatch(btif_sm_handle_t handle, btif_sm_event_t event, 151 void *data) 152 { 153 bt_status_t status = BT_STATUS_SUCCESS; 154 155 btif_sm_cb_t *p_cb = (btif_sm_cb_t*)handle; 156 157 if (p_cb == NULL) 158 { 159 BTIF_TRACE_ERROR1("%s : Invalid handle", __FUNCTION__); 160 return BT_STATUS_FAIL; 161 } 162 163 if (p_cb->p_handlers[p_cb->state](event, data) == FALSE) 164 return BT_STATUS_UNHANDLED; 165 166 return status; 167 } 168 169 /***************************************************************************** 170 ** 171 ** Function btif_sm_change_state 172 ** 173 ** Description Make a transition to the new 'state'. The 'BTIF_SM_EXIT_EVT' 174 ** shall be invoked before exiting the current state. The 175 ** 'BTIF_SM_ENTER_EVT' shall be invoked before entering the new state 176 ** 177 ** Returns BT_STATUS_SUCCESS on success 178 ** BT_STATUS_UNHANDLED if event was not processed 179 ** BT_STATUS_FAIL otherwise 180 ** 181 ******************************************************************************/ 182 bt_status_t btif_sm_change_state(btif_sm_handle_t handle, btif_sm_state_t state) 183 { 184 bt_status_t status = BT_STATUS_SUCCESS; 185 btif_sm_cb_t *p_cb = (btif_sm_cb_t*)handle; 186 187 if (p_cb == NULL) 188 { 189 BTIF_TRACE_ERROR1("%s : Invalid handle", __FUNCTION__); 190 return BT_STATUS_FAIL; 191 } 192 193 /* Send exit event to the current state */ 194 if (p_cb->p_handlers[p_cb->state](BTIF_SM_EXIT_EVT, NULL) == FALSE) 195 status = BT_STATUS_UNHANDLED; 196 197 /* Change to the new state */ 198 p_cb->state = state; 199 200 /* Send enter event to the new state */ 201 if (p_cb->p_handlers[p_cb->state](BTIF_SM_ENTER_EVT, NULL) == FALSE) 202 status = BT_STATUS_UNHANDLED; 203 204 return status; 205 } 206
