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Diffstat (limited to 'src/thread/pth/SDL_syscond.c')
| -rw-r--r-- | src/thread/pth/SDL_syscond.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/src/thread/pth/SDL_syscond.c b/src/thread/pth/SDL_syscond.c new file mode 100644 index 0000000..8ba3f2d --- /dev/null +++ b/src/thread/pth/SDL_syscond.c @@ -0,0 +1,164 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2009 Sam Lantinga + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + + Sam Lantinga + slouken@libsdl.org +*/ +#include "SDL_config.h" + +/* + * GNU pth conditions variables + * + * Patrice Mandin + */ + +#include <pth.h> + +#include "SDL_thread.h" +#include "SDL_sysmutex_c.h" + +struct SDL_cond +{ + pth_cond_t condpth_p; +}; + +/* Create a condition variable */ +SDL_cond * SDL_CreateCond(void) +{ + SDL_cond *cond; + + cond = (SDL_cond *) SDL_malloc(sizeof(SDL_cond)); + if ( cond ) { + if ( pth_cond_init(&(cond->condpth_p)) < 0 ) { + SDL_SetError("pthread_cond_init() failed"); + SDL_free(cond); + cond = NULL; + } + } else { + SDL_OutOfMemory(); + } + return(cond); +} + +/* Destroy a condition variable */ +void SDL_DestroyCond(SDL_cond *cond) +{ + if ( cond ) { + SDL_free(cond); + } +} + +/* Restart one of the threads that are waiting on the condition variable */ +int SDL_CondSignal(SDL_cond *cond) +{ + int retval; + + if ( ! cond ) { + SDL_SetError("Passed a NULL condition variable"); + return -1; + } + + retval = 0; + if ( pth_cond_notify(&(cond->condpth_p), FALSE) != 0 ) { + SDL_SetError("pth_cond_notify() failed"); + retval = -1; + } + return retval; +} + +/* Restart all threads that are waiting on the condition variable */ +int SDL_CondBroadcast(SDL_cond *cond) +{ + int retval; + + if ( ! cond ) { + SDL_SetError("Passed a NULL condition variable"); + return -1; + } + + retval = 0; + if ( pth_cond_notify(&(cond->condpth_p), TRUE) != 0 ) { + SDL_SetError("pth_cond_notify() failed"); + retval = -1; + } + return retval; +} + +/* Wait on the condition variable for at most 'ms' milliseconds. + The mutex must be locked before entering this function! + The mutex is unlocked during the wait, and locked again after the wait. + +Typical use: + +Thread A: + SDL_LockMutex(lock); + while ( ! condition ) { + SDL_CondWait(cond); + } + SDL_UnlockMutex(lock); + +Thread B: + SDL_LockMutex(lock); + ... + condition = true; + ... + SDL_UnlockMutex(lock); + */ +int SDL_CondWaitTimeout(SDL_cond *cond, SDL_mutex *mutex, Uint32 ms) +{ + int retval; + pth_event_t ev; + int sec; + + if ( ! cond ) { + SDL_SetError("Passed a NULL condition variable"); + return -1; + } + + retval = 0; + + sec = ms/1000; + ev = pth_event(PTH_EVENT_TIME, pth_timeout(sec,(ms-sec*1000)*1000)); + + if ( pth_cond_await(&(cond->condpth_p), &(mutex->mutexpth_p), ev) != 0 ) { + SDL_SetError("pth_cond_await() failed"); + retval = -1; + } + + pth_event_free(ev, PTH_FREE_ALL); + + return retval; +} + +/* Wait on the condition variable forever */ +int SDL_CondWait(SDL_cond *cond, SDL_mutex *mutex) +{ + int retval; + + if ( ! cond ) { + SDL_SetError("Passed a NULL condition variable"); + return -1; + } + + retval = 0; + if ( pth_cond_await(&(cond->condpth_p), &(mutex->mutexpth_p), NULL) != 0 ) { + SDL_SetError("pth_cond_await() failed"); + retval = -1; + } + return retval; +} |