1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "btstack_run_loop_posix.c" 39 40 /* 41 * btstack_run_loop.c 42 * 43 * Created by Matthias Ringwald on 6/6/09. 44 */ 45 46 // enable POSIX functions (needed for -std=c99) 47 #define _POSIX_C_SOURCE 200809 48 49 #include "btstack_run_loop_posix.h" 50 51 #include "btstack_run_loop.h" 52 #include "btstack_util.h" 53 #include "btstack_linked_list.h" 54 #include "btstack_debug.h" 55 56 #include <stdio.h> 57 #include <stdlib.h> 58 #include <sys/select.h> 59 #include <sys/time.h> 60 #include <time.h> 61 #include <unistd.h> 62 #include <pthread.h> 63 64 // the run loop 65 static int btstack_run_loop_posix_data_sources_modified; 66 67 static bool btstack_run_loop_posix_exit_requested; 68 69 // to trigger process callbacks other thread 70 static pthread_mutex_t btstack_run_loop_posix_callbacks_mutex = PTHREAD_MUTEX_INITIALIZER; 71 static int btstack_run_loop_posix_process_callbacks_fd; 72 static btstack_data_source_t btstack_run_loop_posix_process_callbacks_ds; 73 74 // to trigger poll data sources from irq 75 static int btstack_run_loop_posix_poll_data_sources_fd; 76 static btstack_data_source_t btstack_run_loop_posix_poll_data_sources_ds; 77 78 // start time. tv_usec/tv_nsec = 0 79 #ifdef _POSIX_MONOTONIC_CLOCK 80 // use monotonic clock if available 81 static struct timespec init_ts; 82 #else 83 // fallback to gettimeofday 84 static struct timeval init_tv; 85 #endif 86 87 /** 88 * Add data_source to run_loop 89 */ 90 static void btstack_run_loop_posix_add_data_source(btstack_data_source_t *ds){ 91 btstack_run_loop_posix_data_sources_modified = 1; 92 btstack_run_loop_base_add_data_source(ds); 93 } 94 95 /** 96 * Remove data_source from run loop 97 */ 98 static bool btstack_run_loop_posix_remove_data_source(btstack_data_source_t *ds){ 99 btstack_run_loop_posix_data_sources_modified = 1; 100 return btstack_run_loop_base_remove_data_source(ds); 101 } 102 103 #ifdef _POSIX_MONOTONIC_CLOCK 104 /** 105 * @brief Returns the timespec which represents the time(stop - start). It might be negative 106 */ 107 static void timespec_diff(struct timespec *start, struct timespec *stop, struct timespec *result){ 108 result->tv_sec = stop->tv_sec - start->tv_sec; 109 if ((stop->tv_nsec - start->tv_nsec) < 0) { 110 result->tv_sec = stop->tv_sec - start->tv_sec - 1; 111 result->tv_nsec = stop->tv_nsec - start->tv_nsec + 1000000000; 112 } else { 113 result->tv_sec = stop->tv_sec - start->tv_sec; 114 result->tv_nsec = stop->tv_nsec - start->tv_nsec; 115 } 116 } 117 118 /** 119 * @brief Convert timespec to miliseconds, might overflow 120 */ 121 static uint64_t timespec_to_milliseconds(struct timespec *a){ 122 uint64_t ret = 0; 123 uint64_t sec_val = (uint64_t)(a->tv_sec); 124 uint64_t nsec_val = (uint64_t)(a->tv_nsec); 125 ret = (sec_val*1000) + (nsec_val/1000000); 126 return ret; 127 } 128 129 /** 130 * @brief Returns the milisecond value of (stop - start). Might overflow 131 */ 132 static uint64_t timespec_diff_milis(struct timespec* start, struct timespec* stop){ 133 struct timespec diff_ts; 134 timespec_diff(start, stop, &diff_ts); 135 return timespec_to_milliseconds(&diff_ts); 136 } 137 #endif 138 139 /** 140 * @brief Queries the current time in ms since start 141 */ 142 static uint32_t btstack_run_loop_posix_get_time_ms(void){ 143 uint32_t time_ms; 144 #ifdef _POSIX_MONOTONIC_CLOCK 145 struct timespec now_ts; 146 clock_gettime(CLOCK_MONOTONIC, &now_ts); 147 time_ms = (uint32_t) timespec_diff_milis(&init_ts, &now_ts); 148 #else 149 struct timeval tv; 150 gettimeofday(&tv, NULL); 151 time_ms = (uint32_t) ((tv.tv_sec - init_tv.tv_sec) * 1000) + (tv.tv_usec / 1000); 152 #endif 153 return time_ms; 154 } 155 156 /** 157 * Execute run_loop 158 */ 159 static void btstack_run_loop_posix_execute(void) { 160 fd_set descriptors_read; 161 fd_set descriptors_write; 162 163 btstack_linked_list_iterator_t it; 164 struct timeval * timeout; 165 struct timeval tv; 166 uint32_t now_ms; 167 168 #ifdef _POSIX_MONOTONIC_CLOCK 169 log_info("POSIX run loop with monotonic clock"); 170 #else 171 log_info("POSIX run loop using ettimeofday fallback."); 172 #endif 173 174 while (btstack_run_loop_posix_exit_requested == false) { 175 // collect FDs 176 FD_ZERO(&descriptors_read); 177 FD_ZERO(&descriptors_write); 178 int highest_fd = -1; 179 btstack_linked_list_iterator_init(&it, &btstack_run_loop_base_data_sources); 180 while (btstack_linked_list_iterator_has_next(&it)){ 181 btstack_data_source_t *ds = (btstack_data_source_t*) btstack_linked_list_iterator_next(&it); 182 if (ds->source.fd < 0) continue; 183 if (ds->flags & DATA_SOURCE_CALLBACK_READ){ 184 FD_SET(ds->source.fd, &descriptors_read); 185 if (ds->source.fd > highest_fd) { 186 highest_fd = ds->source.fd; 187 } 188 log_debug("btstack_run_loop_execute adding fd %u for read", ds->source.fd); 189 } 190 if (ds->flags & DATA_SOURCE_CALLBACK_WRITE){ 191 FD_SET(ds->source.fd, &descriptors_write); 192 if (ds->source.fd > highest_fd) { 193 highest_fd = ds->source.fd; 194 } 195 log_debug("btstack_run_loop_execute adding fd %u for write", ds->source.fd); 196 } 197 } 198 199 // get next timeout 200 timeout = NULL; 201 now_ms = btstack_run_loop_posix_get_time_ms(); 202 int32_t delta_ms = btstack_run_loop_base_get_time_until_timeout(now_ms); 203 if (delta_ms >= 0) { 204 timeout = &tv; 205 tv.tv_sec = delta_ms / 1000; 206 tv.tv_usec = (int) (delta_ms - (tv.tv_sec * 1000)) * 1000; 207 log_debug("btstack_run_loop_execute next timeout in %u ms", delta_ms); 208 } 209 210 // wait for ready FDs 211 select( highest_fd+1 , &descriptors_read, &descriptors_write, NULL, timeout); 212 213 btstack_run_loop_posix_data_sources_modified = 0; 214 btstack_linked_list_iterator_init(&it, &btstack_run_loop_base_data_sources); 215 while (btstack_linked_list_iterator_has_next(&it) && !btstack_run_loop_posix_data_sources_modified){ 216 btstack_data_source_t *ds = (btstack_data_source_t*) btstack_linked_list_iterator_next(&it); 217 log_debug("btstack_run_loop_posix_execute: check ds %p with fd %u\n", ds, ds->source.fd); 218 if (FD_ISSET(ds->source.fd, &descriptors_read)) { 219 log_debug("btstack_run_loop_posix_execute: process read ds %p with fd %u\n", ds, ds->source.fd); 220 ds->process(ds, DATA_SOURCE_CALLBACK_READ); 221 } 222 if (btstack_run_loop_posix_data_sources_modified) break; 223 if (FD_ISSET(ds->source.fd, &descriptors_write)) { 224 log_debug("btstack_run_loop_posix_execute: process write ds %p with fd %u\n", ds, ds->source.fd); 225 ds->process(ds, DATA_SOURCE_CALLBACK_WRITE); 226 } 227 } 228 log_debug("btstack_run_loop_posix_execute: after ds check\n"); 229 230 // process timers 231 now_ms = btstack_run_loop_posix_get_time_ms(); 232 btstack_run_loop_base_process_timers(now_ms); 233 } 234 } 235 236 static void btstack_run_loop_posix_trigger_exit(void){ 237 btstack_run_loop_posix_exit_requested = true; 238 } 239 240 // set timer 241 static void btstack_run_loop_posix_set_timer(btstack_timer_source_t *a, uint32_t timeout_in_ms){ 242 uint32_t time_ms = btstack_run_loop_posix_get_time_ms(); 243 a->timeout = time_ms + timeout_in_ms; 244 log_debug("btstack_run_loop_posix_set_timer to %u ms (now %u, timeout %u)", a->timeout, time_ms, timeout_in_ms); 245 } 246 247 // trigger pipe 248 static void btstack_run_loop_posix_trigger_pipe(int fd){ 249 if (fd < 0) return; 250 const uint8_t x = (uint8_t) 'x'; 251 ssize_t bytes_written = write(fd, &x, 1); 252 UNUSED(bytes_written); 253 } 254 255 // poll data sources from irq 256 257 static void btstack_run_loop_posix_poll_data_sources_handler(btstack_data_source_t * ds, btstack_data_source_callback_type_t callback_type){ 258 UNUSED(callback_type); 259 uint8_t buffer[1]; 260 ssize_t bytes_read = read(ds->source.fd, buffer, 1); 261 UNUSED(bytes_read); 262 // poll data sources 263 btstack_run_loop_base_poll_data_sources(); 264 } 265 266 static void btstack_run_loop_posix_poll_data_sources_from_irq(void){ 267 // trigger run loop 268 btstack_run_loop_posix_trigger_pipe(btstack_run_loop_posix_poll_data_sources_fd); 269 } 270 271 // execute on main thread from same or different thread 272 273 static void btstack_run_loop_posix_process_callbacks_handler(btstack_data_source_t * ds, btstack_data_source_callback_type_t callback_type){ 274 UNUSED(callback_type); 275 uint8_t buffer[1]; 276 ssize_t bytes_read = read(ds->source.fd, buffer, 1); 277 UNUSED(bytes_read); 278 // execute callbacks - protect list with mutex 279 while (1){ 280 pthread_mutex_lock(&btstack_run_loop_posix_callbacks_mutex); 281 btstack_context_callback_registration_t * callback_registration = (btstack_context_callback_registration_t *) btstack_linked_list_pop(&btstack_run_loop_base_callbacks); 282 pthread_mutex_unlock(&btstack_run_loop_posix_callbacks_mutex); 283 if (callback_registration == NULL){ 284 break; 285 } 286 (*callback_registration->callback)(callback_registration->context); 287 } 288 } 289 290 static void btstack_run_loop_posix_execute_on_main_thread(btstack_context_callback_registration_t * callback_registration){ 291 // protect list with mutex 292 pthread_mutex_lock(&btstack_run_loop_posix_callbacks_mutex); 293 btstack_run_loop_base_add_callback(callback_registration); 294 pthread_mutex_unlock(&btstack_run_loop_posix_callbacks_mutex); 295 // trigger run loop 296 btstack_run_loop_posix_trigger_pipe(btstack_run_loop_posix_process_callbacks_fd); 297 } 298 299 //init 300 301 // @return fd >= 0 on success 302 static int btstack_run_loop_posix_register_pipe_datasource(btstack_data_source_t * data_source){ 303 int fildes[2]; // 0 = read, 1 = write 304 int status = pipe(fildes); 305 if (status != 0){ 306 log_error("pipe() failed"); 307 return -1; 308 } 309 data_source->source.fd = fildes[0]; 310 data_source->flags = DATA_SOURCE_CALLBACK_READ; 311 btstack_run_loop_base_add_data_source(data_source); 312 log_info("Pipe: in %u, out %u", fildes[1], fildes[0]); 313 return fildes[1]; 314 } 315 316 static void btstack_run_loop_posix_init(void){ 317 btstack_run_loop_base_init(); 318 319 #ifdef _POSIX_MONOTONIC_CLOCK 320 clock_gettime(CLOCK_MONOTONIC, &init_ts); 321 init_ts.tv_nsec = 0; 322 #else 323 // just assume that we started at tv_usec == 0 324 gettimeofday(&init_tv, NULL); 325 init_tv.tv_usec = 0; 326 #endif 327 328 // setup pipe to trigger process callbacks 329 btstack_run_loop_posix_process_callbacks_ds.process = &btstack_run_loop_posix_process_callbacks_handler; 330 btstack_run_loop_posix_process_callbacks_fd = btstack_run_loop_posix_register_pipe_datasource(&btstack_run_loop_posix_process_callbacks_ds); 331 332 // setup pipe to poll data sources 333 btstack_run_loop_posix_poll_data_sources_ds.process = &btstack_run_loop_posix_poll_data_sources_handler; 334 btstack_run_loop_posix_poll_data_sources_fd = btstack_run_loop_posix_register_pipe_datasource(&btstack_run_loop_posix_poll_data_sources_ds); 335 } 336 337 static const btstack_run_loop_t btstack_run_loop_posix = { 338 &btstack_run_loop_posix_init, 339 &btstack_run_loop_posix_add_data_source, 340 &btstack_run_loop_posix_remove_data_source, 341 &btstack_run_loop_base_enable_data_source_callbacks, 342 &btstack_run_loop_base_disable_data_source_callbacks, 343 &btstack_run_loop_posix_set_timer, 344 &btstack_run_loop_base_add_timer, 345 &btstack_run_loop_base_remove_timer, 346 &btstack_run_loop_posix_execute, 347 &btstack_run_loop_base_dump_timer, 348 &btstack_run_loop_posix_get_time_ms, 349 &btstack_run_loop_posix_poll_data_sources_from_irq, 350 &btstack_run_loop_posix_execute_on_main_thread, 351 &btstack_run_loop_posix_trigger_exit, 352 }; 353 354 /** 355 * Provide btstack_run_loop_posix instance 356 */ 357 const btstack_run_loop_t * btstack_run_loop_posix_get_instance(void){ 358 return &btstack_run_loop_posix; 359 } 360 361