contrib/bind-9.5.2/lib/isc/unix/stdtime.c

   1 /*
   2  * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1999-2001  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and/or distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: stdtime.c,v 1.19 2007/06/19 23:47:18 tbox Exp $ */
  19
  20 /*! \file */
  21
  22 #include <config.h>
  23
  24 #include <stddef.h>     /* NULL */
  25 #include <stdlib.h>     /* NULL */
  26 #include <syslog.h>
  27
  28 #include <sys/time.h>
  29
  30 #include <isc/stdtime.h>
  31 #include <isc/util.h>
  32
  33 #ifndef ISC_FIX_TV_USEC
  34 #define ISC_FIX_TV_USEC 1
  35 #endif
  36
  37 #define US_PER_S 1000000
  38
  39 #if ISC_FIX_TV_USEC
  40 static inline void
  41 fix_tv_usec(struct timeval *tv) {
  42         isc_boolean_t fixed = ISC_FALSE;
  43
  44         if (tv->tv_usec < 0) {
  45                 fixed = ISC_TRUE;
  46                 do {
  47                         tv->tv_sec -= 1;
  48                         tv->tv_usec += US_PER_S;
  49                 } while (tv->tv_usec < 0);
  50         } else if (tv->tv_usec >= US_PER_S) {
  51                 fixed = ISC_TRUE;
  52                 do {
  53                         tv->tv_sec += 1;
  54                         tv->tv_usec -= US_PER_S;
  55                 } while (tv->tv_usec >=US_PER_S);
  56         }
  57         /*
  58          * Call syslog directly as we are called from the logging functions.
  59          */
  60         if (fixed)
  61                 (void)syslog(LOG_ERR, "gettimeofday returned bad tv_usec: corrected");
  62 }
  63 #endif
  64
  65 void
  66 isc_stdtime_get(isc_stdtime_t *t) {
  67         struct timeval tv;
  68
  69         /*
  70          * Set 't' to the number of seconds since 00:00:00 UTC, January 1,
  71          * 1970.
  72          */
  73
  74         REQUIRE(t != NULL);
  75
  76         RUNTIME_CHECK(gettimeofday(&tv, NULL) != -1);
  77
  78 #if ISC_FIX_TV_USEC
  79         fix_tv_usec(&tv);
  80         INSIST(tv.tv_usec >= 0);
  81 #else
  82         INSIST(tv.tv_usec >= 0 && tv.tv_usec < US_PER_S);
  83 #endif
  84
  85         *t = (unsigned int)tv.tv_sec;
  86 }