19682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall/* 29682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL - Simple DirectMedia Layer 39682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall Copyright (C) 1997-2012 Sam Lantinga 49682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 59682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall This library is free software; you can redistribute it and/or 69682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall modify it under the terms of the GNU Lesser General Public 79682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall License as published by the Free Software Foundation; either 89682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall version 2.1 of the License, or (at your option) any later version. 99682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 109682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall This library is distributed in the hope that it will be useful, 119682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall but WITHOUT ANY WARRANTY; without even the implied warranty of 129682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 139682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall Lesser General Public License for more details. 149682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 159682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall You should have received a copy of the GNU Lesser General Public 169682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall License along with this library; if not, write to the Free Software 179682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 189682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 199682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall Sam Lantinga 209682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall slouken@libsdl.org 219682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall*/ 229682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 239682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#include <errno.h> 249682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 259682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#include "SDL_config.h" 269682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 279682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall/* An implementation of semaphores using mutexes and condition variables */ 289682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 299682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#include "SDL_timer.h" 309682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#include "SDL_thread.h" 319682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#include "SDL_systhread_c.h" 329682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 339682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 349682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#if SDL_THREADS_DISABLED 359682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 369682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse HallSDL_sem *SDL_CreateSemaphore(Uint32 initial_value) 379682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 389682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("SDL not configured with thread support"); 399682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return (SDL_sem *)0; 409682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 419682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 429682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallvoid SDL_DestroySemaphore(SDL_sem *sem) 439682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 449682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return; 459682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 469682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 479682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemTryWait(SDL_sem *sem) 489682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 499682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("SDL not configured with thread support"); 509682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 519682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 529682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 539682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) 549682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 559682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("SDL not configured with thread support"); 569682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 579682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 589682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 599682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemWait(SDL_sem *sem) 609682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 619682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("SDL not configured with thread support"); 629682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 639682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 649682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 659682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse HallUint32 SDL_SemValue(SDL_sem *sem) 669682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 679682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return 0; 689682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 699682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 709682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemPost(SDL_sem *sem) 719682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 729682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("SDL not configured with thread support"); 739682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 749682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 759682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 769682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#else 779682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 789682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#include <kos/sem.h> 799682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 809682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallstruct SDL_semaphore 819682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 829682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall semaphore_t sem; 839682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall}; 849682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 859682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse HallSDL_sem *SDL_CreateSemaphore(Uint32 initial_value) 869682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 879682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return (SDL_sem *)sem_create(initial_value); 889682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 899682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 909682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall/* WARNING: 919682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall You cannot call this function when another thread is using the semaphore. 929682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall*/ 939682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallvoid SDL_DestroySemaphore(SDL_sem *sem) 949682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 959682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if ( ! sem ) { 969682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("Passed a NULL semaphore"); 979682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return; 989682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall } 999682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1009682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall sem_destroy(&sem->sem); 1019682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 1029682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1039682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemTryWait(SDL_sem *sem) 1049682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 1059682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall int retval; 1069682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1079682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if ( ! sem ) { 1089682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("Passed a NULL semaphore"); 1099682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 1109682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall } 1119682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1129682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall retval = sem_trywait(&sem->sem); 1139682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if (retval==0) return 0; 1149682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall else return SDL_MUTEX_TIMEDOUT; 1159682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1169682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return retval; 1179682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 1189682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1199682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) 1209682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 1219682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall int retval; 1229682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1239682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if ( ! sem ) { 1249682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("Passed a NULL semaphore"); 1259682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 1269682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall } 1279682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1289682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall /* A timeout of 0 is an easy case */ 1299682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if ( timeout == 0 ) { 1309682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return SDL_SemTryWait(sem); 1319682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall } 1329682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1339682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall retval = sem_wait_timed(&sem->sem,timeout); 1349682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if (retval==-1) retval= SDL_MUTEX_TIMEDOUT; 1359682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1369682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return retval; 1379682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 1389682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1399682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemWait(SDL_sem *sem) 1409682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 1419682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall int retval; 1429682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1439682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if ( ! sem ) { 1449682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("Passed a NULL semaphore"); 1459682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 1469682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall } 1479682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1489682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall while ( ((retval = sem_wait(&sem->sem)) == -1) && (errno == EINTR) ) {} 1499682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return retval; 1509682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 1519682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1529682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse HallUint32 SDL_SemValue(SDL_sem *sem) 1539682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 1549682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if ( ! sem ) { 1559682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("Passed a NULL semaphore"); 1569682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 1579682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall } 1589682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1599682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return sem_count(&sem->sem); 1609682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 1619682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1629682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hallint SDL_SemPost(SDL_sem *sem) 1639682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall{ 1649682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall if ( ! sem ) { 1659682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall SDL_SetError("Passed a NULL semaphore"); 1669682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return -1; 1679682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall } 1689682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1699682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall sem_signal(&sem->sem); 1709682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall return 0; 1719682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall} 1729682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall 1739682c8870b8ff5e4ac2e4c70b759f791c6f38c1fJesse Hall#endif /* SDL_THREADS_DISABLED */ 174