lib/libc/stdtime/time32.c

   1 /*-
   2  * Copyright (c) 2001 FreeBSD Inc.
   3  * All rights reserved.
   4  *
   5  * These routines are for converting time_t to fixed-bit representations
   6  * for use in protocols or storage.  When converting time to a larger
   7  * representation of time_t these routines are expected to assume temporal
   8  * locality and use the 50-year rule to properly set the msb bits.  XXX
   9  *
  10  * Redistribution and use under the terms of the COPYRIGHT file at the
  11  * base of the source tree.
  12  *
  13  * $FreeBSD: head/lib/libc/stdtime/time32.c 98313 2002-06-17 01:42:33Z wollman $
  14  */
  15
  16 #include <sys/types.h>
  17 #include <timeconv.h>
  18
  19 /*
  20  * Convert a 32 bit representation of time_t into time_t.  XXX needs to
  21  * implement the 50-year rule to handle post-2038 conversions.
  22  */
  23 time_t
  24 _time32_to_time(__int32_t t32)
  25 {
  26         return((time_t)t32);
  27 }
  28
  29 /*
  30  * Convert time_t to a 32 bit representation.  If time_t is 64 bits we can
  31  * simply chop it down.   The resulting 32 bit representation can be
  32  * converted back to a temporally local 64 bit time_t using time32_to_time.
  33  */
  34 __int32_t
  35 _time_to_time32(time_t t)
  36 {
  37         return((__int32_t)t);
  38 }
  39
  40 /*
  41  * Convert a 64 bit representation of time_t into time_t.  If time_t is
  42  * represented as 32 bits we can simply chop it and not support times
  43  * past 2038.
  44  */
  45 time_t
  46 _time64_to_time(__int64_t t64)
  47 {
  48         return((time_t)t64);
  49 }
  50
  51 /*
  52  * Convert time_t to a 64 bit representation.  If time_t is represented
  53  * as 32 bits we simply sign-extend and do not support times past 2038.
  54  */
  55 __int64_t
  56 _time_to_time64(time_t t)
  57 {
  58         return((__int64_t)t);
  59 }
  60
  61 /*
  62  * Convert to/from 'long'.  Depending on the sizeof(long) this may or
  63  * may not require using the 50-year rule.
  64  */
  65 long
  66 _time_to_long(time_t t)
  67 {
  68         if (sizeof(long) == sizeof(__int64_t))
  69                 return(_time_to_time64(t));
  70         return((long)t);
  71 }
  72
  73 time_t
  74 _long_to_time(long tlong)
  75 {
  76         if (sizeof(long) == sizeof(__int32_t))
  77                 return(_time32_to_time(tlong));
  78         return((time_t)tlong);
  79 }
  80
  81 /*
  82  * Convert to/from 'int'.  Depending on the sizeof(int) this may or
  83  * may not require using the 50-year rule.
  84  */
  85 int
  86 _time_to_int(time_t t)
  87 {
  88         if (sizeof(int) == sizeof(__int64_t))
  89                 return(_time_to_time64(t));
  90         return((int)t);
  91 }
  92
  93 time_t
  94 _int_to_time(int tint)
  95 {
  96         if (sizeof(int) == sizeof(__int32_t))
  97                 return(_time32_to_time(tint));
  98         return((time_t)tint);
  99 }