src/mq/mq_timedreceive.c

   1 #include <mqueue.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 ssize_t mq_timedreceive(mqd_t mqd, char *restrict msg, size_t len, unsigned *restrict prio, const struct timespec *restrict at)
   9 {
  10 #ifdef SYS_mq_timedreceive_time64
  11         time_t s = at ? at->tv_sec : 0;
  12         long ns = at ? at->tv_nsec : 0;
  13         long r = -ENOSYS;
  14         if (SYS_mq_timedreceive == SYS_mq_timedreceive_time64 || !IS32BIT(s))
  15                 r = __syscall_cp(SYS_mq_timedreceive_time64, mqd, msg, len, prio,
  16                         at ? ((long long []){at->tv_sec, at->tv_nsec}) : 0);
  17         if (SYS_mq_timedreceive == SYS_mq_timedreceive_time64 || r != -ENOSYS)
  18                 return __syscall_ret(r);
  19         return syscall_cp(SYS_mq_timedreceive, mqd, msg, len, prio,
  20                 at ? ((long[]){CLAMP(s), ns}) : 0);
  21 #else
  22         return syscall_cp(SYS_mq_timedreceive, mqd, msg, len, prio, at);
  23 #endif
  24 }