sysdeps/unix/sysv/linux/adjtime.c

   1 /* Copyright (C) 1995-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <limits.h>
  20 #include <sys/time.h>
  21 #include <sys/timex.h>
  22
  23 #define MAX_SEC (INT_MAX / 1000000L - 2)
  24 #define MIN_SEC (INT_MIN / 1000000L + 2)
  25
  26 #ifndef MOD_OFFSET
  27 #define modes mode
  28 #endif
  29
  30 #ifndef TIMEVAL
  31 #define TIMEVAL timeval
  32 #endif
  33
  34 #ifndef TIMEX
  35 #define TIMEX timex
  36 #endif
  37
  38 #ifndef ADJTIME
  39 #define ADJTIME __adjtime
  40 #endif
  41
  42 #ifndef ADJTIMEX
  43 #define NO_LOCAL_ADJTIME
  44 #define ADJTIMEX(x) __adjtimex (x)
  45 #endif
  46
  47 #ifndef LINKAGE
  48 #define LINKAGE
  49 #endif
  50
  51 LINKAGE int
  52 ADJTIME (const struct TIMEVAL *itv, struct TIMEVAL *otv)
  53 {
  54   struct TIMEX tntx;
  55
  56   if (itv)
  57     {
  58       struct TIMEVAL tmp;
  59
  60       /* We will do some check here. */
  61       tmp.tv_sec = itv->tv_sec + itv->tv_usec / 1000000L;
  62       tmp.tv_usec = itv->tv_usec % 1000000L;
  63       if (tmp.tv_sec > MAX_SEC || tmp.tv_sec < MIN_SEC)
  64         {
  65           __set_errno (EINVAL);
  66           return -1;
  67         }
  68       tntx.offset = tmp.tv_usec + tmp.tv_sec * 1000000L;
  69       tntx.modes = ADJ_OFFSET_SINGLESHOT;
  70     }
  71   else
  72     tntx.modes = ADJ_OFFSET_SS_READ;
  73
  74   if (__glibc_unlikely (ADJTIMEX (&tntx) < 0))
  75     return -1;
  76
  77   if (otv)
  78     {
  79       if (tntx.offset < 0)
  80         {
  81           otv->tv_usec = -(-tntx.offset % 1000000);
  82           otv->tv_sec  = -(-tntx.offset / 1000000);
  83         }
  84       else
  85         {
  86           otv->tv_usec = tntx.offset % 1000000;
  87           otv->tv_sec  = tntx.offset / 1000000;
  88         }
  89     }
  90   return 0;
  91 }
  92
  93 #ifdef NO_LOCAL_ADJTIME
  94 weak_alias (__adjtime, adjtime)
  95 #endif