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#define _REENTRANT
#define _DIETLIBC_SOURCE
#include <threads.h>
#include <sys/futex.h>
#include <errno.h>
int __mtx_trylock(mtx_t* mutex,int* lockval) {
int i;
thrd_t me=thrd_current();
/* attempt to lock the mutex with an atomic instruction */
if ((i=__sync_val_compare_and_swap(&mutex->lock,0,1))==0) {
mutex->owner=me;
return thrd_success;
}
if ((mutex->type&mtx_recursive) && mutex->owner==me) {
if (__sync_add_and_fetch(&mutex->lock,1)>1000) {
__sync_add_and_fetch(&mutex->lock,-1);
return thrd_error;
}
return thrd_success;
}
if (lockval) *lockval=i;
return thrd_busy;
}
int mtx_trylock(mtx_t* mutex) {
return __mtx_trylock(mutex,NULL);
}
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