1/****************************************************************************** 2 * 3 * Copyright (C) 2014 Google, Inc. 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#define LOG_TAG "bt_core_module" 20 21#include <assert.h> 22#include <dlfcn.h> 23#include <pthread.h> 24#include <string.h> 25 26#include "btcore/include/module.h" 27#include "osi/include/allocator.h" 28#include "osi/include/hash_functions.h" 29#include "osi/include/hash_map.h" 30#include "osi/include/log.h" 31#include "osi/include/osi.h" 32 33typedef enum { 34 MODULE_STATE_NONE = 0, 35 MODULE_STATE_INITIALIZED = 1, 36 MODULE_STATE_STARTED = 2 37} module_state_t; 38 39static const size_t number_of_metadata_buckets = 42; 40static hash_map_t *metadata; 41// Include this lock for now for correctness, while the startup sequence is being refactored 42static pthread_mutex_t metadata_lock; 43 44static bool call_lifecycle_function(module_lifecycle_fn function); 45static module_state_t get_module_state(const module_t *module); 46static void set_module_state(const module_t *module, module_state_t state); 47 48void module_management_start(void) { 49 metadata = hash_map_new( 50 number_of_metadata_buckets, 51 hash_function_pointer, 52 NULL, 53 osi_free, 54 NULL 55 ); 56 57 pthread_mutex_init(&metadata_lock, NULL); 58} 59 60void module_management_stop(void) { 61 if (!metadata) 62 return; 63 64 hash_map_free(metadata); 65 metadata = NULL; 66 67 pthread_mutex_destroy(&metadata_lock); 68} 69 70const module_t *get_module(const char *name) { 71 module_t* module = (module_t *)dlsym(RTLD_DEFAULT, name); 72 assert(module); 73 return module; 74} 75 76bool module_init(const module_t *module) { 77 assert(metadata != NULL); 78 assert(module != NULL); 79 assert(get_module_state(module) == MODULE_STATE_NONE); 80 81 LOG_INFO(LOG_TAG, "%s Initializing module \"%s\"", __func__, module->name); 82 if (!call_lifecycle_function(module->init)) { 83 LOG_ERROR(LOG_TAG, "%s Failed to initialize module \"%s\"", 84 __func__, module->name); 85 return false; 86 } 87 LOG_INFO(LOG_TAG, "%s Initialized module \"%s\"", __func__, module->name); 88 89 set_module_state(module, MODULE_STATE_INITIALIZED); 90 return true; 91} 92 93bool module_start_up(const module_t *module) { 94 assert(metadata != NULL); 95 assert(module != NULL); 96 // TODO(zachoverflow): remove module->init check once automagic order/call is in place. 97 // This hack is here so modules which don't require init don't have to have useless calls 98 // as we're converting the startup sequence. 99 assert(get_module_state(module) == MODULE_STATE_INITIALIZED || module->init == NULL); 100 101 LOG_INFO(LOG_TAG, "%s Starting module \"%s\"", __func__, module->name); 102 if (!call_lifecycle_function(module->start_up)) { 103 LOG_ERROR(LOG_TAG, "%s Failed to start up module \"%s\"", 104 __func__, module->name); 105 return false; 106 } 107 LOG_INFO(LOG_TAG, "%s Started module \"%s\"", __func__, module->name); 108 109 set_module_state(module, MODULE_STATE_STARTED); 110 return true; 111} 112 113void module_shut_down(const module_t *module) { 114 assert(metadata != NULL); 115 assert(module != NULL); 116 module_state_t state = get_module_state(module); 117 assert(state <= MODULE_STATE_STARTED); 118 119 // Only something to do if the module was actually started 120 if (state < MODULE_STATE_STARTED) 121 return; 122 123 LOG_INFO(LOG_TAG, "%s Shutting down module \"%s\"", __func__, module->name); 124 if (!call_lifecycle_function(module->shut_down)) { 125 LOG_ERROR(LOG_TAG, "%s Failed to shutdown module \"%s\". Continuing anyway.", 126 __func__, module->name); 127 } 128 LOG_INFO(LOG_TAG, "%s Shutdown of module \"%s\" completed", 129 __func__, module->name); 130 131 set_module_state(module, MODULE_STATE_INITIALIZED); 132} 133 134void module_clean_up(const module_t *module) { 135 assert(metadata != NULL); 136 assert(module != NULL); 137 module_state_t state = get_module_state(module); 138 assert(state <= MODULE_STATE_INITIALIZED); 139 140 // Only something to do if the module was actually initialized 141 if (state < MODULE_STATE_INITIALIZED) 142 return; 143 144 LOG_INFO(LOG_TAG, "%s Cleaning up module \"%s\"", __func__, module->name); 145 if (!call_lifecycle_function(module->clean_up)) { 146 LOG_ERROR(LOG_TAG, "%s Failed to cleanup module \"%s\". Continuing anyway.", 147 __func__, module->name); 148 } 149 LOG_INFO(LOG_TAG, "%s Cleanup of module \"%s\" completed", 150 __func__, module->name); 151 152 set_module_state(module, MODULE_STATE_NONE); 153} 154 155static bool call_lifecycle_function(module_lifecycle_fn function) { 156 // A NULL lifecycle function means it isn't needed, so assume success 157 if (!function) 158 return true; 159 160 future_t *future = function(); 161 162 // A NULL future means synchronous success 163 if (!future) 164 return true; 165 166 // Otherwise fall back to the future 167 return future_await(future); 168} 169 170static module_state_t get_module_state(const module_t *module) { 171 pthread_mutex_lock(&metadata_lock); 172 module_state_t *state_ptr = hash_map_get(metadata, module); 173 pthread_mutex_unlock(&metadata_lock); 174 175 return state_ptr ? *state_ptr : MODULE_STATE_NONE; 176} 177 178static void set_module_state(const module_t *module, module_state_t state) { 179 pthread_mutex_lock(&metadata_lock); 180 181 module_state_t *state_ptr = hash_map_get(metadata, module); 182 if (!state_ptr) { 183 state_ptr = osi_malloc(sizeof(module_state_t)); 184 hash_map_set(metadata, module, state_ptr); 185 } 186 187 pthread_mutex_unlock(&metadata_lock); 188 189 *state_ptr = state; 190} 191 192// TODO(zachoverflow): remove when everything modulized 193// Temporary callback-wrapper-related code 194 195typedef struct { 196 const module_t *module; 197 thread_t *lifecycle_thread; 198 thread_t *callback_thread; // we don't own this thread 199 thread_fn callback; 200 bool success; 201} callbacked_wrapper_t; 202 203static void run_wrapped_start_up(void *context); 204static void post_result_to_callback(void *context); 205 206void module_start_up_callbacked_wrapper( 207 const module_t *module, 208 thread_t *callback_thread, 209 thread_fn callback) { 210 callbacked_wrapper_t *wrapper = osi_calloc(sizeof(callbacked_wrapper_t)); 211 212 wrapper->module = module; 213 wrapper->lifecycle_thread = thread_new("module_wrapper"); 214 wrapper->callback_thread = callback_thread; 215 wrapper->callback = callback; 216 217 // Run the actual module start up 218 thread_post(wrapper->lifecycle_thread, run_wrapped_start_up, wrapper); 219} 220 221static void run_wrapped_start_up(void *context) { 222 assert(context); 223 224 callbacked_wrapper_t *wrapper = context; 225 wrapper->success = module_start_up(wrapper->module); 226 227 // Post the result back to the callback 228 thread_post(wrapper->callback_thread, post_result_to_callback, wrapper); 229} 230 231static void post_result_to_callback(void *context) { 232 assert(context); 233 234 callbacked_wrapper_t *wrapper = context; 235 236 // Save the values we need for callback 237 void *result = wrapper->success ? FUTURE_SUCCESS : FUTURE_FAIL; 238 thread_fn callback = wrapper->callback; 239 240 // Clean up the resources we used 241 thread_free(wrapper->lifecycle_thread); 242 osi_free(wrapper); 243 244 callback(result); 245} 246