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#include <pthread.h>
#include <time.h>
#include <errno.h>
#include "futex.h"
#include "syscall.h"
#include "pthread_impl.h"
#define IS32BIT(x) !((x)+0x80000000ULL>>32)
#define CLAMP(x) (int)(IS32BIT(x) ? (x) : 0x7fffffffU+((0ULL+(x))>>63))
static int __futex4_cp(volatile void *addr, int op, int val, const struct timespec *to)
{
int r;
#ifdef SYS_futex_time64
time_t s = to ? to->tv_sec : 0;
long ns = to ? to->tv_nsec : 0;
r = -ENOSYS;
if (SYS_futex == SYS_futex_time64 || !IS32BIT(s))
r = __syscall_cp(SYS_futex_time64, addr, op, val,
to ? ((long long[]){s, ns}) : 0);
if (SYS_futex == SYS_futex_time64 || r!=-ENOSYS) return r;
to = to ? (void *)(long[]){CLAMP(s), ns} : 0;
#endif
r = __syscall_cp(SYS_futex, addr, op, val, to);
if (r != -ENOSYS) return r;
return __syscall_cp(SYS_futex, addr, op & ~FUTEX_PRIVATE, val, to);
}
static volatile int dummy = 0;
weak_alias(dummy, __eintr_valid_flag);
int __timedwait_cp(volatile int *addr, int val,
clockid_t clk, const struct timespec *at, int priv)
{
int r;
struct timespec to, *top=0;
if (priv) priv = FUTEX_PRIVATE;
if (at) {
if (at->tv_nsec >= 1000000000UL) return EINVAL;
if (__clock_gettime(clk, &to)) return EINVAL;
to.tv_sec = at->tv_sec - to.tv_sec;
if ((to.tv_nsec = at->tv_nsec - to.tv_nsec) < 0) {
to.tv_sec--;
to.tv_nsec += 1000000000;
}
if (to.tv_sec < 0) return ETIMEDOUT;
top = &to;
}
r = -__futex4_cp(addr, FUTEX_WAIT|priv, val, top);
if (r != EINTR && r != ETIMEDOUT && r != ECANCELED) r = 0;
/* Mitigate bug in old kernels wrongly reporting EINTR for non-
* interrupting (SA_RESTART) signal handlers. This is only practical
* when NO interrupting signal handlers have been installed, and
* works by sigaction tracking whether that's the case. */
if (r == EINTR && !__eintr_valid_flag) r = 0;
return r;
}
int __timedwait(volatile int *addr, int val,
clockid_t clk, const struct timespec *at, int priv)
{
int cs, r;
__pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
r = __timedwait_cp(addr, val, clk, at, priv);
__pthread_setcancelstate(cs, 0);
return r;
}
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