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
  14 #include <sys/cdefs.h>
  15 __FBSDID("$FreeBSD$");
  16
  17 #include <sys/types.h>
  18 #include <timeconv.h>
  19
  20 /*
  21  * Convert a 32 bit representation of time_t into time_t.  XXX needs to
  22  * implement the 50-year rule to handle post-2038 conversions.
  23  */
  24 time_t
  25 _time32_to_time(__int32_t t32)
  26 {
  27     return((time_t)t32);
  28 }
  29
  30 /*
  31  * Convert time_t to a 32 bit representation.  If time_t is 64 bits we can
  32  * simply chop it down.   The resulting 32 bit representation can be
  33  * converted back to a temporally local 64 bit time_t using time32_to_time.
  34  */
  35 __int32_t
  36 _time_to_time32(time_t t)
  37 {
  38     return((__int32_t)t);
  39 }
  40
  41 /*
  42  * Convert a 64 bit representation of time_t into time_t.  If time_t is
  43  * represented as 32 bits we can simply chop it and not support times
  44  * past 2038.
  45  */
  46 time_t
  47 _time64_to_time(__int64_t t64)
  48 {
  49     return((time_t)t64);
  50 }
  51
  52 /*
  53  * Convert time_t to a 64 bit representation.  If time_t is represented
  54  * as 32 bits we simply sign-extend and do not support times past 2038.
  55  */
  56 __int64_t
  57 _time_to_time64(time_t t)
  58 {
  59     return((__int64_t)t);
  60 }
  61
  62 /*
  63  * Convert to/from 'long'.  Depending on the sizeof(long) this may or
  64  * may not require using the 50-year rule.
  65  */
  66 long
  67 _time_to_long(time_t t)
  68 {
  69     if (sizeof(long) == sizeof(__int64_t))
  70         return(_time_to_time64(t));
  71     return((long)t);
  72 }
  73
  74 time_t
  75 _long_to_time(long tlong)
  76 {
  77     if (sizeof(long) == sizeof(__int32_t))
  78         return(_time32_to_time(tlong));
  79     return((time_t)tlong);
  80 }
  81
  82 /*
  83  * Convert to/from 'int'.  Depending on the sizeof(int) this may or
  84  * may not require using the 50-year rule.
  85  */
  86 int
  87 _time_to_int(time_t t)
  88 {
  89     if (sizeof(int) == sizeof(__int64_t))
  90         return(_time_to_time64(t));
  91     return((int)t);
  92 }
  93
  94 time_t
  95 _int_to_time(int tint)
  96 {
  97     if (sizeof(int) == sizeof(__int32_t))
  98         return(_time32_to_time(tint));
  99     return((time_t)tint);
 100 }