src/time/clock_nanosleep.c

   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);