Mercurial > sdl-ios-xcode
annotate src/thread/linux/SDL_syssem.c @ 1345:7f32b9bede06
Fixes for Visual C++ 6.0
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Tue, 07 Feb 2006 18:36:54 +0000 |
| parents | 604d73db6802 |
| children | c71e05b4dc2e |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
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Updated copyright information and removed rcs id lines (problematic in branch merges)
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parents:
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|
3 Copyright (C) 1997-2006 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
|
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Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
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|
6 modify it under the terms of the GNU Lesser General Public |
| 0 | 7 License as published by the Free Software Foundation; either |
|
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c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
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|
8 version 2.1 of the License, or (at your option) any later version. |
| 0 | 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 | |
|
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c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
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diff
changeset
|
13 Lesser General Public License for more details. |
| 0 | 14 |
|
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
1300
diff
changeset
|
15 You should have received a copy of the GNU Lesser General Public |
|
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
1300
diff
changeset
|
16 License along with this library; if not, write to the Free Software |
|
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
1300
diff
changeset
|
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 0 | 18 |
| 19 Sam Lantinga | |
|
252
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Updated the source with the correct e-mail address
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20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
|
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Removed uses of stdlib.h and string.h
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23 #include "SDL_stdlib.h" |
| 0 | 24 #include "SDL_error.h" |
| 25 #include "SDL_thread.h" | |
| 26 #include "SDL_timer.h" | |
| 27 | |
| 28 #ifdef linux | |
| 29 /* Look to see if glibc is available, and if so, what version */ | |
| 30 #include <features.h> | |
| 31 | |
| 32 #if (__GLIBC__ == 2) && (__GLIBC_MINOR__ == 0) | |
| 33 #warning Working around a bug in glibc 2.0 pthreads | |
| 34 #undef SDL_USE_PTHREADS | |
| 35 /* The bug is actually a problem where threads are suspended, but don't | |
| 36 wake up when the thread manager sends them a signal. This is a problem | |
| 37 with thread creation too, but it happens less often. :-/ | |
| 38 We avoid this by using System V IPC for semaphores. | |
| 39 */ | |
| 40 #endif /* glibc 2.0 */ | |
| 41 #endif /* linux */ | |
| 42 | |
| 43 #ifdef SDL_USE_PTHREADS | |
| 44 | |
| 45 #ifdef SDL_NO_PTHREAD_SEMAPHORES | |
|
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ae6e6b73333f
Cleaned up the OpenBSD port, thanks to Peter Valchev
Sam Lantinga <slouken@lokigames.com>
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46 #include "generic/SDL_syssem.c" |
| 0 | 47 #else |
| 48 | |
|
18
d9e3595b63d5
Added pthread.h - necessary on some configurations
Sam Lantinga <slouken@lokigames.com>
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diff
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49 #include <pthread.h> |
| 0 | 50 #include <semaphore.h> |
| 51 | |
| 52 /* Wrapper around POSIX 1003.1b semaphores */ | |
| 53 | |
| 54 #ifdef MACOSX | |
| 55 #define USE_NAMED_SEMAPHORES | |
| 56 #endif /* MACOSX */ | |
| 57 | |
| 58 struct SDL_semaphore { | |
| 59 sem_t *sem; | |
| 60 #ifndef USE_NAMED_SEMAPHORES | |
| 61 sem_t sem_data; | |
| 62 #endif | |
| 63 }; | |
| 64 | |
| 65 /* Create a semaphore, initialized with value */ | |
| 66 SDL_sem *SDL_CreateSemaphore(Uint32 initial_value) | |
| 67 { | |
|
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Use SDL_ prefixed versions of C library functions.
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parents:
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68 SDL_sem *sem = (SDL_sem *) SDL_malloc(sizeof(SDL_sem)); |
| 0 | 69 if ( sem ) { |
| 70 #ifdef USE_NAMED_SEMAPHORES | |
| 71 static int semnum = 0; | |
| 72 char name[32]; | |
| 73 | |
|
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Removed uses of stdlib.h and string.h
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parents:
1336
diff
changeset
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74 SDL_snprintf(name, SDL_arraysize(name), "/SDL_sem-%d-%4.4d", getpid(), semnum++); |
| 0 | 75 sem->sem = sem_open(name, O_CREAT, 0600, initial_value); |
| 76 if ( sem->sem == (sem_t *)SEM_FAILED ) { | |
| 77 SDL_SetError("sem_open(%s) failed", name); | |
|
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Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
78 SDL_free(sem); |
| 0 | 79 sem = NULL; |
| 80 } else { | |
| 81 sem_unlink(name); | |
| 82 } | |
| 83 #else | |
| 84 if ( sem_init(&sem->sem_data, 0, initial_value) < 0 ) { | |
| 85 SDL_SetError("sem_init() failed"); | |
|
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Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
86 SDL_free(sem); |
| 0 | 87 sem = NULL; |
| 88 } else { | |
| 89 sem->sem = &sem->sem_data; | |
| 90 } | |
| 91 #endif /* USE_NAMED_SEMAPHORES */ | |
| 92 } else { | |
| 93 SDL_OutOfMemory(); | |
| 94 } | |
| 95 return sem; | |
| 96 } | |
| 97 | |
| 98 void SDL_DestroySemaphore(SDL_sem *sem) | |
| 99 { | |
| 100 if ( sem ) { | |
| 101 #ifdef USE_NAMED_SEMAPHORES | |
| 102 sem_close(sem->sem); | |
| 103 #else | |
| 104 sem_destroy(sem->sem); | |
| 105 #endif | |
|
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3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
106 SDL_free(sem); |
| 0 | 107 } |
| 108 } | |
| 109 | |
| 110 int SDL_SemTryWait(SDL_sem *sem) | |
| 111 { | |
| 112 int retval; | |
| 113 | |
| 114 if ( ! sem ) { | |
| 115 SDL_SetError("Passed a NULL semaphore"); | |
| 116 return -1; | |
| 117 } | |
| 118 retval = SDL_MUTEX_TIMEDOUT; | |
| 119 if ( sem_trywait(sem->sem) == 0 ) { | |
| 120 retval = 0; | |
| 121 } | |
| 122 return retval; | |
| 123 } | |
| 124 | |
| 125 int SDL_SemWait(SDL_sem *sem) | |
| 126 { | |
| 127 int retval; | |
| 128 | |
| 129 if ( ! sem ) { | |
| 130 SDL_SetError("Passed a NULL semaphore"); | |
| 131 return -1; | |
| 132 } | |
| 133 | |
| 134 retval = sem_wait(sem->sem); | |
| 135 if ( retval < 0 ) { | |
| 136 SDL_SetError("sem_wait() failed"); | |
| 137 } | |
| 138 return retval; | |
| 139 } | |
| 140 | |
| 141 int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) | |
| 142 { | |
| 143 int retval; | |
| 144 | |
| 145 if ( ! sem ) { | |
| 146 SDL_SetError("Passed a NULL semaphore"); | |
| 147 return -1; | |
| 148 } | |
| 149 | |
| 150 /* Try the easy cases first */ | |
| 151 if ( timeout == 0 ) { | |
| 152 return SDL_SemTryWait(sem); | |
| 153 } | |
| 154 if ( timeout == SDL_MUTEX_MAXWAIT ) { | |
| 155 return SDL_SemWait(sem); | |
| 156 } | |
| 157 | |
| 158 /* Ack! We have to busy wait... */ | |
| 159 timeout += SDL_GetTicks(); | |
| 160 do { | |
| 161 retval = SDL_SemTryWait(sem); | |
| 162 if ( retval == 0 ) { | |
| 163 break; | |
| 164 } | |
| 165 SDL_Delay(1); | |
| 166 } while ( SDL_GetTicks() < timeout ); | |
| 167 | |
| 168 return retval; | |
| 169 } | |
| 170 | |
| 171 Uint32 SDL_SemValue(SDL_sem *sem) | |
| 172 { | |
| 173 int ret = 0; | |
| 174 if ( sem ) { | |
| 175 sem_getvalue(sem->sem, &ret); | |
| 176 if ( ret < 0 ) { | |
| 177 ret = 0; | |
| 178 } | |
| 179 } | |
| 180 return (Uint32)ret; | |
| 181 } | |
| 182 | |
| 183 int SDL_SemPost(SDL_sem *sem) | |
| 184 { | |
| 185 int retval; | |
| 186 | |
| 187 if ( ! sem ) { | |
| 188 SDL_SetError("Passed a NULL semaphore"); | |
| 189 return -1; | |
| 190 } | |
| 191 | |
| 192 retval = sem_post(sem->sem); | |
| 193 if ( retval < 0 ) { | |
| 194 SDL_SetError("sem_post() failed"); | |
| 195 } | |
| 196 return retval; | |
| 197 } | |
| 198 | |
| 199 #endif /* NO_PTHREAD_SEMAPHORES */ | |
| 200 | |
| 201 #else /* System V IPC implementation */ | |
| 202 | |
| 203 #include <stdio.h> | |
| 204 #include <stdlib.h> | |
| 205 #include <sys/types.h> | |
| 206 #include <sys/ipc.h> | |
| 207 #include <sys/sem.h> | |
| 208 #include <errno.h> | |
| 209 | |
| 210 #include "SDL_error.h" | |
| 211 #include "SDL_thread.h" | |
| 212 | |
| 213 | |
| 214 struct SDL_semaphore { | |
| 215 int id; | |
| 216 }; | |
| 217 | |
| 218 /* Not defined by many operating systems, use configure to detect */ | |
| 219 #if !defined(HAVE_SEMUN) | |
| 220 union semun { | |
| 221 int val; | |
| 222 struct semid_ds *buf; | |
| 223 ushort *array; | |
| 224 }; | |
| 225 #endif | |
| 226 | |
| 227 static struct sembuf op_trywait[2] = { | |
| 228 { 0, -1, (IPC_NOWAIT|SEM_UNDO) } /* Decrement semaphore, no block */ | |
| 229 }; | |
| 230 static struct sembuf op_wait[2] = { | |
| 231 { 0, -1, SEM_UNDO } /* Decrement semaphore */ | |
| 232 }; | |
| 233 static struct sembuf op_post[1] = { | |
| 234 { 0, 1, (IPC_NOWAIT|SEM_UNDO) } /* Increment semaphore */ | |
| 235 }; | |
| 236 | |
| 237 /* Create a blockable semaphore */ | |
| 238 SDL_sem *SDL_CreateSemaphore(Uint32 initial_value) | |
| 239 { | |
| 240 extern int _creating_thread_lock; /* SDL_threads.c */ | |
| 241 SDL_sem *sem; | |
| 242 union semun init; | |
| 243 key_t key; | |
| 244 | |
|
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3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
245 sem = (SDL_sem *)SDL_malloc(sizeof(*sem)); |
| 0 | 246 if ( sem == NULL ) { |
| 247 SDL_OutOfMemory(); | |
| 248 return(NULL); | |
| 249 } | |
| 250 /* This flag is true if we are creating the thread manager sem, | |
| 251 which is never freed. This allows us to reuse the same sem. | |
| 252 */ | |
| 253 if ( _creating_thread_lock ) { | |
| 254 key = 'S'+'D'+'L'; | |
| 255 } else { | |
| 256 key = IPC_PRIVATE; | |
| 257 } | |
| 258 /* Keep trying to create sem while we don't own the requested key */ | |
| 259 do { | |
| 260 if ( key != IPC_PRIVATE ) { | |
| 261 ++key; | |
| 262 } | |
| 263 sem->id = semget(key, 1, (0600|IPC_CREAT)); | |
| 264 } while ((sem->id < 0) && (key != IPC_PRIVATE) && (errno == EACCES)); | |
| 265 | |
| 266 /* Report the error if we eventually failed */ | |
| 267 if ( sem->id < 0 ) { | |
| 268 SDL_SetError("Couldn't create semaphore"); | |
|
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3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
269 SDL_free(sem); |
| 0 | 270 return(NULL); |
| 271 } | |
| 272 init.val = initial_value; /* Initialize semaphore */ | |
| 273 semctl(sem->id, 0, SETVAL, init); | |
| 274 return(sem); | |
| 275 } | |
| 276 | |
| 277 void SDL_DestroySemaphore(SDL_sem *sem) | |
| 278 { | |
| 279 if ( sem ) { | |
| 280 #ifdef _SGI_SOURCE | |
| 281 semctl(sem->id, 0, IPC_RMID); | |
| 282 #else | |
| 283 union semun dummy; | |
| 284 dummy.val = 0; | |
| 285 semctl(sem->id, 0, IPC_RMID, dummy); | |
| 286 #endif | |
|
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3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
287 SDL_free(sem); |
| 0 | 288 } |
| 289 } | |
| 290 | |
| 291 int SDL_SemTryWait(SDL_sem *sem) | |
| 292 { | |
| 293 int retval; | |
| 294 | |
| 295 if ( ! sem ) { | |
| 296 SDL_SetError("Passed a NULL semaphore"); | |
| 297 return -1; | |
| 298 } | |
| 299 | |
| 300 retval = 0; | |
| 301 tryagain: | |
| 302 if ( semop(sem->id, op_trywait, 1) < 0 ) { | |
| 303 if ( errno == EINTR ) { | |
| 304 goto tryagain; | |
| 305 } | |
| 306 retval = SDL_MUTEX_TIMEDOUT; | |
| 307 } | |
| 308 return retval; | |
| 309 } | |
| 310 | |
| 311 int SDL_SemWait(SDL_sem *sem) | |
| 312 { | |
| 313 int retval; | |
| 314 | |
| 315 if ( ! sem ) { | |
| 316 SDL_SetError("Passed a NULL semaphore"); | |
| 317 return -1; | |
| 318 } | |
| 319 | |
| 320 retval = 0; | |
| 321 tryagain: | |
| 322 if ( semop(sem->id, op_wait, 1) < 0 ) { | |
| 323 if ( errno == EINTR ) { | |
| 324 goto tryagain; | |
| 325 } | |
| 326 SDL_SetError("Semaphore operation error"); | |
| 327 retval = -1; | |
| 328 } | |
| 329 return retval; | |
| 330 } | |
| 331 | |
| 332 int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) | |
| 333 { | |
| 334 int retval; | |
| 335 | |
| 336 if ( ! sem ) { | |
| 337 SDL_SetError("Passed a NULL semaphore"); | |
| 338 return -1; | |
| 339 } | |
| 340 | |
| 341 /* Try the easy cases first */ | |
| 342 if ( timeout == 0 ) { | |
| 343 return SDL_SemTryWait(sem); | |
| 344 } | |
| 345 if ( timeout == SDL_MUTEX_MAXWAIT ) { | |
| 346 return SDL_SemWait(sem); | |
| 347 } | |
| 348 | |
| 349 /* Ack! We have to busy wait... */ | |
| 350 timeout += SDL_GetTicks(); | |
| 351 do { | |
| 352 retval = SDL_SemTryWait(sem); | |
| 353 if ( retval == 0 ) { | |
| 354 break; | |
| 355 } | |
| 356 SDL_Delay(1); | |
| 357 } while ( SDL_GetTicks() < timeout ); | |
| 358 | |
| 359 return retval; | |
| 360 } | |
| 361 | |
| 362 Uint32 SDL_SemValue(SDL_sem *sem) | |
| 363 { | |
| 364 int semval; | |
| 365 Uint32 value; | |
| 366 | |
| 367 value = 0; | |
| 368 if ( sem ) { | |
| 369 tryagain: | |
| 370 #ifdef _SGI_SOURCE | |
| 371 semval = semctl(sem->id, 0, GETVAL); | |
| 372 #else | |
| 373 { | |
| 374 union semun arg; | |
| 375 arg.val = 0; | |
| 376 semval = semctl(sem->id, 0, GETVAL, arg); | |
| 377 } | |
| 378 #endif | |
| 379 if ( semval < 0 ) { | |
| 380 if ( errno == EINTR ) { | |
| 381 goto tryagain; | |
| 382 } | |
| 383 } else { | |
| 384 value = (Uint32)semval; | |
| 385 } | |
| 386 } | |
| 387 return value; | |
| 388 } | |
| 389 | |
| 390 int SDL_SemPost(SDL_sem *sem) | |
| 391 { | |
| 392 int retval; | |
| 393 | |
| 394 if ( ! sem ) { | |
| 395 SDL_SetError("Passed a NULL semaphore"); | |
| 396 return -1; | |
| 397 } | |
| 398 | |
| 399 retval = 0; | |
| 400 tryagain: | |
| 401 if ( semop(sem->id, op_post, 1) < 0 ) { | |
| 402 if ( errno == EINTR ) { | |
| 403 goto tryagain; | |
| 404 } | |
| 405 SDL_SetError("Semaphore operation error"); | |
| 406 retval = -1; | |
| 407 } | |
| 408 return retval; | |
| 409 } | |
| 410 | |
| 411 #endif /* SDL_USE_PTHREADS */ |