github.com/afumu/libc@v0.0.6/musl/src/time/clock_nanosleep.c (about)

     1  #include <time.h>
     2  #include <errno.h>
     3  #include "syscall.h"
     4  
     5  #define IS32BIT(x) !((x)+0x80000000ULL>>32)
     6  #define CLAMP(x) (int)(IS32BIT(x) ? (x) : 0x7fffffffU+((0ULL+(x))>>63))
     7  
     8  int __clock_nanosleep(clockid_t clk, int flags, const struct timespec *req, struct timespec *rem)
     9  {
    10  	if (clk == CLOCK_THREAD_CPUTIME_ID) return EINVAL;
    11  #ifdef SYS_clock_nanosleep_time64
    12  	time_t s = req->tv_sec;
    13  	long ns = req->tv_nsec;
    14  	int r = -ENOSYS;
    15  	if (SYS_clock_nanosleep == SYS_clock_nanosleep_time64 || !IS32BIT(s))
    16  		r = __syscall_cp(SYS_clock_nanosleep_time64, clk, flags,
    17  			((long long[]){s, ns}), rem);
    18  	if (SYS_clock_nanosleep == SYS_clock_nanosleep_time64 || r!=-ENOSYS)
    19  		return -r;
    20  	long long extra = s - CLAMP(s);
    21  	long ts32[2] = { CLAMP(s), ns };
    22  	if (clk == CLOCK_REALTIME && !flags)
    23  		r = __syscall_cp(SYS_nanosleep, &ts32, &ts32);
    24  	else
    25  		r = __syscall_cp(SYS_clock_nanosleep, clk, flags, &ts32, &ts32);
    26  	if (r==-EINTR && rem && !(flags & TIMER_ABSTIME)) {
    27  		rem->tv_sec = ts32[0] + extra;
    28  		rem->tv_nsec = ts32[1];
    29  	}
    30  	return -r;
    31  #else
    32  	if (clk == CLOCK_REALTIME && !flags)
    33  		return -__syscall_cp(SYS_nanosleep, req, rem);
    34  	return -__syscall_cp(SYS_clock_nanosleep, clk, flags, req, rem);
    35  #endif
    36  }
    37  
    38  weak_alias(__clock_nanosleep, clock_nanosleep);