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 MATTHIAS 24 * RINGWALD 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_run_loop_base.h" 53 #include "btstack_util.h" 54 #include "btstack_linked_list.h" 55 #include "btstack_debug.h" 56 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <sys/select.h> 60 #include <sys/time.h> 61 #include <time.h> 62 #include <unistd.h> 63 64 // the run loop 65 static int data_sources_modified; 66 67 // start time. tv_usec/tv_nsec = 0 68 #ifdef _POSIX_MONOTONIC_CLOCK 69 // use monotonic clock if available 70 static struct timespec init_ts; 71 #else 72 // fallback to gettimeofday 73 static struct timeval init_tv; 74 #endif 75 76 /** 77 * Add data_source to run_loop 78 */ 79 static void btstack_run_loop_posix_add_data_source(btstack_data_source_t *ds){ 80 data_sources_modified = 1; 81 btstack_run_loop_base_add_data_source(ds); 82 } 83 84 /** 85 * Remove data_source from run loop 86 */ 87 static bool btstack_run_loop_posix_remove_data_source(btstack_data_source_t *ds){ 88 data_sources_modified = 1; 89 return btstack_run_loop_base_remove_data_source(ds); 90 } 91 92 #ifdef _POSIX_MONOTONIC_CLOCK 93 /** 94 * @brief Returns the timespec which represents the time(stop - start). It might be negative 95 */ 96 static void timespec_diff(struct timespec *start, struct timespec *stop, struct timespec *result){ 97 result->tv_sec = stop->tv_sec - start->tv_sec; 98 if ((stop->tv_nsec - start->tv_nsec) < 0) { 99 result->tv_sec = stop->tv_sec - start->tv_sec - 1; 100 result->tv_nsec = stop->tv_nsec - start->tv_nsec + 1000000000; 101 } else { 102 result->tv_sec = stop->tv_sec - start->tv_sec; 103 result->tv_nsec = stop->tv_nsec - start->tv_nsec; 104 } 105 } 106 107 /** 108 * @brief Convert timespec to miliseconds, might overflow 109 */ 110 static uint64_t timespec_to_milliseconds(struct timespec *a){ 111 uint64_t ret = 0; 112 uint64_t sec_val = (uint64_t)(a->tv_sec); 113 uint64_t nsec_val = (uint64_t)(a->tv_nsec); 114 ret = (sec_val*1000) + (nsec_val/1000000); 115 return ret; 116 } 117 118 /** 119 * @brief Returns the milisecond value of (stop - start). Might overflow 120 */ 121 static uint64_t timespec_diff_milis(struct timespec* start, struct timespec* stop){ 122 struct timespec diff_ts; 123 timespec_diff(start, stop, &diff_ts); 124 return timespec_to_milliseconds(&diff_ts); 125 } 126 #endif 127 128 /** 129 * @brief Queries the current time in ms since start 130 */ 131 static uint32_t btstack_run_loop_posix_get_time_ms(void){ 132 uint32_t time_ms; 133 #ifdef _POSIX_MONOTONIC_CLOCK 134 struct timespec now_ts; 135 clock_gettime(CLOCK_MONOTONIC, &now_ts); 136 time_ms = (uint32_t) timespec_diff_milis(&init_ts, &now_ts); 137 #else 138 struct timeval tv; 139 gettimeofday(&tv, NULL); 140 time_ms = (uint32_t) ((tv.tv_sec - init_tv.tv_sec) * 1000) + (tv.tv_usec / 1000); 141 #endif 142 return time_ms; 143 } 144 145 /** 146 * Execute run_loop 147 */ 148 static void btstack_run_loop_posix_execute(void) { 149 fd_set descriptors_read; 150 fd_set descriptors_write; 151 152 btstack_linked_list_iterator_t it; 153 struct timeval * timeout; 154 struct timeval tv; 155 uint32_t now_ms; 156 157 #ifdef _POSIX_MONOTONIC_CLOCK 158 log_info("POSIX run loop with monotonic clock"); 159 #else 160 log_info("POSIX run loop using ettimeofday fallback."); 161 #endif 162 163 while (true) { 164 // collect FDs 165 FD_ZERO(&descriptors_read); 166 FD_ZERO(&descriptors_write); 167 int highest_fd = -1; 168 btstack_linked_list_iterator_init(&it, &btstack_run_loop_base_data_sources); 169 while (btstack_linked_list_iterator_has_next(&it)){ 170 btstack_data_source_t *ds = (btstack_data_source_t*) btstack_linked_list_iterator_next(&it); 171 if (ds->source.fd < 0) continue; 172 if (ds->flags & DATA_SOURCE_CALLBACK_READ){ 173 FD_SET(ds->source.fd, &descriptors_read); 174 if (ds->source.fd > highest_fd) { 175 highest_fd = ds->source.fd; 176 } 177 log_debug("btstack_run_loop_execute adding fd %u for read", ds->source.fd); 178 } 179 if (ds->flags & DATA_SOURCE_CALLBACK_WRITE){ 180 FD_SET(ds->source.fd, &descriptors_write); 181 if (ds->source.fd > highest_fd) { 182 highest_fd = ds->source.fd; 183 } 184 log_debug("btstack_run_loop_execute adding fd %u for write", ds->source.fd); 185 } 186 } 187 188 // get next timeout 189 timeout = NULL; 190 now_ms = btstack_run_loop_posix_get_time_ms(); 191 int32_t delta_ms = btstack_run_loop_base_get_time_until_timeout(now_ms); 192 if (delta_ms >= 0) { 193 timeout = &tv; 194 tv.tv_sec = delta_ms / 1000; 195 tv.tv_usec = (int) (delta_ms - (tv.tv_sec * 1000)) * 1000; 196 log_debug("btstack_run_loop_execute next timeout in %u ms", delta_ms); 197 } 198 199 // wait for ready FDs 200 select( highest_fd+1 , &descriptors_read, &descriptors_write, NULL, timeout); 201 202 203 data_sources_modified = 0; 204 btstack_linked_list_iterator_init(&it, &btstack_run_loop_base_data_sources); 205 while (btstack_linked_list_iterator_has_next(&it) && !data_sources_modified){ 206 btstack_data_source_t *ds = (btstack_data_source_t*) btstack_linked_list_iterator_next(&it); 207 log_debug("btstack_run_loop_posix_execute: check ds %p with fd %u\n", ds, ds->source.fd); 208 if (FD_ISSET(ds->source.fd, &descriptors_read)) { 209 log_debug("btstack_run_loop_posix_execute: process read ds %p with fd %u\n", ds, ds->source.fd); 210 ds->process(ds, DATA_SOURCE_CALLBACK_READ); 211 } 212 if (data_sources_modified) break; 213 if (FD_ISSET(ds->source.fd, &descriptors_write)) { 214 log_debug("btstack_run_loop_posix_execute: process write ds %p with fd %u\n", ds, ds->source.fd); 215 ds->process(ds, DATA_SOURCE_CALLBACK_WRITE); 216 } 217 } 218 log_debug("btstack_run_loop_posix_execute: after ds check\n"); 219 220 // process timers 221 now_ms = btstack_run_loop_posix_get_time_ms(); 222 btstack_run_loop_base_process_timers(now_ms); 223 } 224 } 225 226 // set timer 227 static void btstack_run_loop_posix_set_timer(btstack_timer_source_t *a, uint32_t timeout_in_ms){ 228 uint32_t time_ms = btstack_run_loop_posix_get_time_ms(); 229 a->timeout = time_ms + timeout_in_ms; 230 log_debug("btstack_run_loop_posix_set_timer to %u ms (now %u, timeout %u)", a->timeout, time_ms, timeout_in_ms); 231 } 232 233 static void btstack_run_loop_posix_init(void){ 234 btstack_run_loop_base_init(); 235 236 #ifdef _POSIX_MONOTONIC_CLOCK 237 clock_gettime(CLOCK_MONOTONIC, &init_ts); 238 init_ts.tv_nsec = 0; 239 #else 240 // just assume that we started at tv_usec == 0 241 gettimeofday(&init_tv, NULL); 242 init_tv.tv_usec = 0; 243 #endif 244 } 245 246 247 static const btstack_run_loop_t btstack_run_loop_posix = { 248 &btstack_run_loop_posix_init, 249 &btstack_run_loop_posix_add_data_source, 250 &btstack_run_loop_posix_remove_data_source, 251 &btstack_run_loop_base_enable_data_source_callbacks, 252 &btstack_run_loop_base_disable_data_source_callbacks, 253 &btstack_run_loop_posix_set_timer, 254 &btstack_run_loop_base_add_timer, 255 &btstack_run_loop_base_remove_timer, 256 &btstack_run_loop_posix_execute, 257 &btstack_run_loop_base_dump_timer, 258 &btstack_run_loop_posix_get_time_ms, 259 }; 260 261 /** 262 * Provide btstack_run_loop_posix instance 263 */ 264 const btstack_run_loop_t * btstack_run_loop_posix_get_instance(void){ 265 return &btstack_run_loop_posix; 266 } 267 268