usr/src/lib/libast/common/tm/tvsleep.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23
  24 #include <tv.h>
  25 #include <tm.h>
  26
  27 #include "FEATURE/tvlib"
  28
  29 #if !_lib_nanosleep
  30 # if _lib_select
  31 #  if _sys_select
  32 #   include <sys/select.h>
  33 #  else
  34 #   include <sys/socket.h>
  35 #  endif
  36 # else
  37 #  if !_lib_usleep
  38 #   if _lib_poll_notimer
  39 #    undef _lib_poll
  40 #   endif
  41 #   if _lib_poll
  42 #    include <poll.h>
  43 #   endif
  44 #  endif
  45 # endif
  46 #endif
  47
  48 /*
  49  * sleep for tv
  50  * non-zero exit if sleep did not complete
  51  * with remaining time in rv
  52  */
  53
  54 int
  55 tvsleep(register const Tv_t* tv, register Tv_t* rv)
  56 {
  57
  58 #if _lib_nanosleep
  59
  60         struct timespec stv;
  61         struct timespec srv;
  62         int             r;
  63
  64         stv.tv_sec = tv->tv_sec;
  65         stv.tv_nsec = tv->tv_nsec;
  66         if ((r = nanosleep(&stv, &srv)) && rv)
  67         {
  68                 rv->tv_sec = srv.tv_sec;
  69                 rv->tv_nsec = srv.tv_nsec;
  70         }
  71         return r;
  72
  73 #else
  74
  75 #if _lib_select
  76
  77         struct timeval  stv;
  78
  79         stv.tv_sec = tv->tv_sec;
  80         stv.tv_usec = tv->tv_nsec / 1000;
  81         if (select(0, NiL, NiL, NiL, &stv) < 0)
  82         {
  83                 if (rv)
  84                         *rv = *tv;
  85                 return -1;
  86         }
  87         if (rv)
  88         {
  89                 rv->tv_sec = stv.tv_sec;
  90                 rv->tv_nsec = stv.tv_usec * 1000;
  91         }
  92         return 0;
  93
  94 #else
  95
  96         unsigned int            s = tv->tv_sec;
  97         uint32_t                n = tv->tv_nsec;
  98
  99 #if _lib_usleep
 100
 101
 102         unsigned long           t;
 103
 104         if (t = (n + 999L) / 1000L)
 105         {
 106                 usleep(t);
 107                 s -= t / 1000000L;
 108                 n = 0;
 109         }
 110
 111 #else
 112
 113 #if _lib_poll
 114
 115         struct pollfd           pfd;
 116         int                     t;
 117
 118         if ((t = (n + 999999L) / 1000000L) > 0)
 119         {
 120                 poll(&pfd, 0, t);
 121                 s -= t / 1000L;
 122                 n = 0;
 123         }
 124
 125 #endif
 126
 127 #endif
 128
 129         if ((s += (n + 999999999L) / 1000000000L) && (s = sleep(s)))
 130         {
 131                 if (rv)
 132                 {
 133                         rv->tv_sec = s;
 134                         rv->tv_nsec = 0;
 135                 }
 136                 return -1;
 137         }
 138         return 0;
 139
 140 #endif
 141
 142 #endif
 143
 144 }