github.com/afumu/libc@v0.0.6/musl/src/select/pselect.c (about)

     1  #include <sys/select.h>
     2  #include <signal.h>
     3  #include <stdint.h>
     4  #include <errno.h>
     5  #include "syscall.h"
     6  
     7  #define IS32BIT(x) !((x)+0x80000000ULL>>32)
     8  #define CLAMP(x) (int)(IS32BIT(x) ? (x) : 0x7fffffffU+((0ULL+(x))>>63))
     9  
    10  int pselect(int n, fd_set *restrict rfds, fd_set *restrict wfds, fd_set *restrict efds, const struct timespec *restrict ts, const sigset_t *restrict mask)
    11  {
    12  	syscall_arg_t data[2] = { (uintptr_t)mask, _NSIG/8 };
    13  	time_t s = ts ? ts->tv_sec : 0;
    14  	long ns = ts ? ts->tv_nsec : 0;
    15  #ifdef SYS_pselect6_time64
    16  	int r = -ENOSYS;
    17  	if (SYS_pselect6 == SYS_pselect6_time64 || !IS32BIT(s))
    18  		r = __syscall_cp(SYS_pselect6_time64, n, rfds, wfds, efds,
    19  			ts ? ((long long[]){s, ns}) : 0, data);
    20  	if (SYS_pselect6 == SYS_pselect6_time64 || r!=-ENOSYS)
    21  		return __syscall_ret(r);
    22  	s = CLAMP(s);
    23  #endif
    24  	return syscall_cp(SYS_pselect6, n, rfds, wfds, efds,
    25  		ts ? ((long[]){s, ns}) : 0, data);
    26  }