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 "osi/include/allocator.h" 27 #include "osi/include/hash_map.h" 28 #include "btcore/include/module.h" 29 #include "osi/include/osi.h" 30 #include "osi/include/hash_functions.h" 31 #include "osi/include/log.h" 32 33 typedef enum { 34 MODULE_STATE_NONE = 0, 35 MODULE_STATE_INITIALIZED = 1, 36 MODULE_STATE_STARTED = 2 37 } module_state_t; 38 39 static const size_t number_of_metadata_buckets = 42; 40 static hash_map_t *metadata; 41 // Include this lock for now for correctness, while the startup sequence is being refactored 42 static pthread_mutex_t metadata_lock; 43 44 static bool call_lifecycle_function(module_lifecycle_fn function); 45 static module_state_t get_module_state(const module_t *module); 46 static void set_module_state(const module_t *module, module_state_t state); 47 48 void 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 60 void 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 70 const 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 76 bool 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 if (!call_lifecycle_function(module->init)) { 82 LOG_ERROR("%s failed to initialize \"%s\"", __func__, module->name); 83 return false; 84 } 85 86 set_module_state(module, MODULE_STATE_INITIALIZED); 87 return true; 88 } 89 90 bool module_start_up(const module_t *module) { 91 assert(metadata != NULL); 92 assert(module != NULL); 93 // TODO(zachoverflow): remove module->init check once automagic order/call is in place. 94 // This hack is here so modules which don't require init don't have to have useless calls 95 // as we're converting the startup sequence. 96 assert(get_module_state(module) == MODULE_STATE_INITIALIZED || module->init == NULL); 97 98 if (!call_lifecycle_function(module->start_up)) { 99 LOG_ERROR("%s failed to start up \"%s\"", __func__, module->name); 100 return false; 101 } 102 103 set_module_state(module, MODULE_STATE_STARTED); 104 return true; 105 } 106 107 void module_shut_down(const module_t *module) { 108 assert(metadata != NULL); 109 assert(module != NULL); 110 module_state_t state = get_module_state(module); 111 assert(state <= MODULE_STATE_STARTED); 112 113 // Only something to do if the module was actually started 114 if (state < MODULE_STATE_STARTED) 115 return; 116 117 if (!call_lifecycle_function(module->shut_down)) 118 LOG_ERROR("%s found \"%s\" reported failure during shutdown. Continuing anyway.", __func__, module->name); 119 120 set_module_state(module, MODULE_STATE_INITIALIZED); 121 } 122 123 void module_clean_up(const module_t *module) { 124 assert(metadata != NULL); 125 assert(module != NULL); 126 module_state_t state = get_module_state(module); 127 assert(state <= MODULE_STATE_INITIALIZED); 128 129 // Only something to do if the module was actually initialized 130 if (state < MODULE_STATE_INITIALIZED) 131 return; 132 133 if (!call_lifecycle_function(module->clean_up)) 134 LOG_ERROR("%s found \"%s\" reported failure during cleanup. Continuing anyway.", __func__, module->name); 135 136 set_module_state(module, MODULE_STATE_NONE); 137 } 138 139 static bool call_lifecycle_function(module_lifecycle_fn function) { 140 // A NULL lifecycle function means it isn't needed, so assume success 141 if (!function) 142 return true; 143 144 future_t *future = function(); 145 146 // A NULL future means synchronous success 147 if (!future) 148 return true; 149 150 // Otherwise fall back to the future 151 return future_await(future); 152 } 153 154 static module_state_t get_module_state(const module_t *module) { 155 pthread_mutex_lock(&metadata_lock); 156 module_state_t *state_ptr = hash_map_get(metadata, module); 157 pthread_mutex_unlock(&metadata_lock); 158 159 return state_ptr ? *state_ptr : MODULE_STATE_NONE; 160 } 161 162 static void set_module_state(const module_t *module, module_state_t state) { 163 pthread_mutex_lock(&metadata_lock); 164 165 module_state_t *state_ptr = hash_map_get(metadata, module); 166 if (!state_ptr) { 167 state_ptr = osi_malloc(sizeof(module_state_t)); 168 hash_map_set(metadata, module, state_ptr); 169 } 170 171 pthread_mutex_unlock(&metadata_lock); 172 173 *state_ptr = state; 174 } 175 176 // TODO(zachoverflow): remove when everything modulized 177 // Temporary callback-wrapper-related code 178 179 typedef struct { 180 const module_t *module; 181 thread_t *lifecycle_thread; 182 thread_t *callback_thread; // we don't own this thread 183 thread_fn callback; 184 bool success; 185 } callbacked_wrapper_t; 186 187 static void run_wrapped_start_up(void *context); 188 static void post_result_to_callback(void *context); 189 190 void module_start_up_callbacked_wrapper( 191 const module_t *module, 192 thread_t *callback_thread, 193 thread_fn callback) { 194 callbacked_wrapper_t *wrapper = osi_calloc(sizeof(callbacked_wrapper_t)); 195 196 wrapper->module = module; 197 wrapper->lifecycle_thread = thread_new("module_wrapper"); 198 wrapper->callback_thread = callback_thread; 199 wrapper->callback = callback; 200 201 // Run the actual module start up 202 thread_post(wrapper->lifecycle_thread, run_wrapped_start_up, wrapper); 203 } 204 205 static void run_wrapped_start_up(void *context) { 206 assert(context); 207 208 callbacked_wrapper_t *wrapper = context; 209 wrapper->success = module_start_up(wrapper->module); 210 211 // Post the result back to the callback 212 thread_post(wrapper->callback_thread, post_result_to_callback, wrapper); 213 } 214 215 static void post_result_to_callback(void *context) { 216 assert(context); 217 218 callbacked_wrapper_t *wrapper = context; 219 220 // Save the values we need for callback 221 void *result = wrapper->success ? FUTURE_SUCCESS : FUTURE_FAIL; 222 thread_fn callback = wrapper->callback; 223 224 // Clean up the resources we used 225 thread_stop(wrapper->lifecycle_thread); 226 osi_free(wrapper); 227 228 callback(result); 229 } 230
