| 1 | /* |
| 2 | SDL - Simple DirectMedia Layer |
| 3 | Copyright (C) 1997-2009 Sam Lantinga |
| 4 | |
| 5 | This library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | This library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with this library; if not, write to the Free Software |
| 17 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | |
| 19 | Sam Lantinga |
| 20 | slouken@libsdl.org |
| 21 | */ |
| 22 | #include "SDL_config.h" |
| 23 | |
| 24 | #ifdef SDL_TIMER_UNIX |
| 25 | |
| 26 | #include <stdio.h> |
| 27 | #include <sys/time.h> |
| 28 | #include <signal.h> |
| 29 | #include <unistd.h> |
| 30 | #include <string.h> |
| 31 | #include <errno.h> |
| 32 | |
| 33 | #include "SDL_timer.h" |
| 34 | #include "../SDL_timer_c.h" |
| 35 | |
| 36 | /* The clock_gettime provides monotonous time, so we should use it if |
| 37 | it's available. The clock_gettime function is behind ifdef |
| 38 | for __USE_POSIX199309 |
| 39 | Tommi Kyntola (tommi.kyntola@ray.fi) 27/09/2005 |
| 40 | */ |
| 41 | #if HAVE_NANOSLEEP || HAVE_CLOCK_GETTIME |
| 42 | #include <time.h> |
| 43 | #endif |
| 44 | |
| 45 | #if SDL_THREAD_PTH |
| 46 | #include <pth.h> |
| 47 | #endif |
| 48 | |
| 49 | #if SDL_THREADS_DISABLED |
| 50 | #define USE_ITIMER |
| 51 | #endif |
| 52 | |
| 53 | /* The first ticks value of the application */ |
| 54 | #ifdef HAVE_CLOCK_GETTIME |
| 55 | static struct timespec start; |
| 56 | #else |
| 57 | static struct timeval start; |
| 58 | #endif /* HAVE_CLOCK_GETTIME */ |
| 59 | |
| 60 | |
| 61 | void SDL_StartTicks(void) |
| 62 | { |
| 63 | /* Set first ticks value */ |
| 64 | #if HAVE_CLOCK_GETTIME |
| 65 | clock_gettime(CLOCK_MONOTONIC,&start); |
| 66 | #else |
| 67 | gettimeofday(&start, NULL); |
| 68 | #endif |
| 69 | } |
| 70 | |
| 71 | Uint32 SDL_GetTicks (void) |
| 72 | { |
| 73 | #if HAVE_CLOCK_GETTIME |
| 74 | Uint32 ticks; |
| 75 | struct timespec now; |
| 76 | clock_gettime(CLOCK_MONOTONIC,&now); |
| 77 | ticks=(now.tv_sec-start.tv_sec)*1000+(now.tv_nsec-start.tv_nsec)/1000000; |
| 78 | return(ticks); |
| 79 | #else |
| 80 | Uint32 ticks; |
| 81 | struct timeval now; |
| 82 | gettimeofday(&now, NULL); |
| 83 | ticks=(now.tv_sec-start.tv_sec)*1000+(now.tv_usec-start.tv_usec)/1000; |
| 84 | return(ticks); |
| 85 | #endif |
| 86 | } |
| 87 | |
| 88 | void SDL_Delay (Uint32 ms) |
| 89 | { |
| 90 | #if SDL_THREAD_PTH |
| 91 | pth_time_t tv; |
| 92 | tv.tv_sec = ms/1000; |
| 93 | tv.tv_usec = (ms%1000)*1000; |
| 94 | pth_nap(tv); |
| 95 | #else |
| 96 | int was_error; |
| 97 | |
| 98 | #if HAVE_NANOSLEEP |
| 99 | struct timespec elapsed, tv; |
| 100 | #else |
| 101 | struct timeval tv; |
| 102 | Uint32 then, now, elapsed; |
| 103 | #endif |
| 104 | |
| 105 | /* Set the timeout interval */ |
| 106 | #if HAVE_NANOSLEEP |
| 107 | elapsed.tv_sec = ms/1000; |
| 108 | elapsed.tv_nsec = (ms%1000)*1000000; |
| 109 | #else |
| 110 | then = SDL_GetTicks(); |
| 111 | #endif |
| 112 | do { |
| 113 | errno = 0; |
| 114 | |
| 115 | #if HAVE_NANOSLEEP |
| 116 | tv.tv_sec = elapsed.tv_sec; |
| 117 | tv.tv_nsec = elapsed.tv_nsec; |
| 118 | was_error = nanosleep(&tv, &elapsed); |
| 119 | #else |
| 120 | /* Calculate the time interval left (in case of interrupt) */ |
| 121 | now = SDL_GetTicks(); |
| 122 | elapsed = (now-then); |
| 123 | then = now; |
| 124 | if ( elapsed >= ms ) { |
| 125 | break; |
| 126 | } |
| 127 | ms -= elapsed; |
| 128 | tv.tv_sec = ms/1000; |
| 129 | tv.tv_usec = (ms%1000)*1000; |
| 130 | |
| 131 | was_error = select(0, NULL, NULL, NULL, &tv); |
| 132 | #endif /* HAVE_NANOSLEEP */ |
| 133 | } while ( was_error && (errno == EINTR) ); |
| 134 | #endif /* SDL_THREAD_PTH */ |
| 135 | } |
| 136 | |
| 137 | #ifdef USE_ITIMER |
| 138 | |
| 139 | static void HandleAlarm(int sig) |
| 140 | { |
| 141 | Uint32 ms; |
| 142 | |
| 143 | if ( SDL_alarm_callback ) { |
| 144 | ms = (*SDL_alarm_callback)(SDL_alarm_interval); |
| 145 | if ( ms != SDL_alarm_interval ) { |
| 146 | SDL_SetTimer(ms, SDL_alarm_callback); |
| 147 | } |
| 148 | } |
| 149 | } |
| 150 | |
| 151 | int SDL_SYS_TimerInit(void) |
| 152 | { |
| 153 | struct sigaction action; |
| 154 | |
| 155 | /* Set the alarm handler (Linux specific) */ |
| 156 | SDL_memset(&action, 0, sizeof(action)); |
| 157 | action.sa_handler = HandleAlarm; |
| 158 | action.sa_flags = SA_RESTART; |
| 159 | sigemptyset(&action.sa_mask); |
| 160 | sigaction(SIGALRM, &action, NULL); |
| 161 | return(0); |
| 162 | } |
| 163 | |
| 164 | void SDL_SYS_TimerQuit(void) |
| 165 | { |
| 166 | SDL_SetTimer(0, NULL); |
| 167 | } |
| 168 | |
| 169 | int SDL_SYS_StartTimer(void) |
| 170 | { |
| 171 | struct itimerval timer; |
| 172 | |
| 173 | timer.it_value.tv_sec = (SDL_alarm_interval/1000); |
| 174 | timer.it_value.tv_usec = (SDL_alarm_interval%1000)*1000; |
| 175 | timer.it_interval.tv_sec = (SDL_alarm_interval/1000); |
| 176 | timer.it_interval.tv_usec = (SDL_alarm_interval%1000)*1000; |
| 177 | setitimer(ITIMER_REAL, &timer, NULL); |
| 178 | return(0); |
| 179 | } |
| 180 | |
| 181 | void SDL_SYS_StopTimer(void) |
| 182 | { |
| 183 | struct itimerval timer; |
| 184 | |
| 185 | SDL_memset(&timer, 0, (sizeof timer)); |
| 186 | setitimer(ITIMER_REAL, &timer, NULL); |
| 187 | } |
| 188 | |
| 189 | #else /* USE_ITIMER */ |
| 190 | |
| 191 | #include "SDL_thread.h" |
| 192 | |
| 193 | /* Data to handle a single periodic alarm */ |
| 194 | static int timer_alive = 0; |
| 195 | static SDL_Thread *timer = NULL; |
| 196 | |
| 197 | static int RunTimer(void *unused) |
| 198 | { |
| 199 | while ( timer_alive ) { |
| 200 | if ( SDL_timer_running ) { |
| 201 | SDL_ThreadedTimerCheck(); |
| 202 | } |
| 203 | SDL_Delay(1); |
| 204 | } |
| 205 | return(0); |
| 206 | } |
| 207 | |
| 208 | /* This is only called if the event thread is not running */ |
| 209 | int SDL_SYS_TimerInit(void) |
| 210 | { |
| 211 | timer_alive = 1; |
| 212 | timer = SDL_CreateThread(RunTimer, NULL); |
| 213 | if ( timer == NULL ) |
| 214 | return(-1); |
| 215 | return(SDL_SetTimerThreaded(1)); |
| 216 | } |
| 217 | |
| 218 | void SDL_SYS_TimerQuit(void) |
| 219 | { |
| 220 | timer_alive = 0; |
| 221 | if ( timer ) { |
| 222 | SDL_WaitThread(timer, NULL); |
| 223 | timer = NULL; |
| 224 | } |
| 225 | } |
| 226 | |
| 227 | int SDL_SYS_StartTimer(void) |
| 228 | { |
| 229 | SDL_SetError("Internal logic error: Linux uses threaded timer"); |
| 230 | return(-1); |
| 231 | } |
| 232 | |
| 233 | void SDL_SYS_StopTimer(void) |
| 234 | { |
| 235 | return; |
| 236 | } |
| 237 | |
| 238 | #endif /* USE_ITIMER */ |
| 239 | |
| 240 | #endif /* SDL_TIMER_UNIX */ |