xref: /dflybsd-src/lib/libc/stdtime/time32.c (revision f422879087c500dba8e04d24e154ef95c1e8f027)
1*f4228790SPeter Avalos /*-
2*f4228790SPeter Avalos  * Copyright (c) 2001 FreeBSD Inc.
3*f4228790SPeter Avalos  * All rights reserved.
4*f4228790SPeter Avalos  *
5*f4228790SPeter Avalos  * These routines are for converting time_t to fixed-bit representations
6*f4228790SPeter Avalos  * for use in protocols or storage.  When converting time to a larger
7*f4228790SPeter Avalos  * representation of time_t these routines are expected to assume temporal
8*f4228790SPeter Avalos  * locality and use the 50-year rule to properly set the msb bits.  XXX
9*f4228790SPeter Avalos  *
10*f4228790SPeter Avalos  * Redistribution and use under the terms of the COPYRIGHT file at the
11*f4228790SPeter Avalos  * base of the source tree.
12*f4228790SPeter Avalos  *
13*f4228790SPeter Avalos  * $FreeBSD: src/lib/libc/stdtime/time32.c,v 1.5 2002/06/17 01:42:29 wollman Exp $
14*f4228790SPeter Avalos  */
15*f4228790SPeter Avalos 
16*f4228790SPeter Avalos #include <sys/types.h>
17*f4228790SPeter Avalos #include <timeconv.h>
18*f4228790SPeter Avalos 
19*f4228790SPeter Avalos /*
20*f4228790SPeter Avalos  * Convert a 32 bit representation of time_t into time_t.  XXX needs to
21*f4228790SPeter Avalos  * implement the 50-year rule to handle post-2038 conversions.
22*f4228790SPeter Avalos  */
23*f4228790SPeter Avalos time_t
24*f4228790SPeter Avalos _time32_to_time(__int32_t t32)
25*f4228790SPeter Avalos {
26*f4228790SPeter Avalos 
27*f4228790SPeter Avalos 	return((time_t)t32);
28*f4228790SPeter Avalos }
29*f4228790SPeter Avalos 
30*f4228790SPeter Avalos /*
31*f4228790SPeter Avalos  * Convert time_t to a 32 bit representation.  If time_t is 64 bits we can
32*f4228790SPeter Avalos  * simply chop it down.   The resulting 32 bit representation can be
33*f4228790SPeter Avalos  * converted back to a temporally local 64 bit time_t using time32_to_time.
34*f4228790SPeter Avalos  */
35*f4228790SPeter Avalos __int32_t
36*f4228790SPeter Avalos _time_to_time32(time_t t)
37*f4228790SPeter Avalos {
38*f4228790SPeter Avalos 
39*f4228790SPeter Avalos 	return((__int32_t)t);
40*f4228790SPeter Avalos }
41*f4228790SPeter Avalos 
42*f4228790SPeter Avalos /*
43*f4228790SPeter Avalos  * Convert a 64 bit representation of time_t into time_t.  If time_t is
44*f4228790SPeter Avalos  * represented as 32 bits we can simply chop it and not support times
45*f4228790SPeter Avalos  * past 2038.
46*f4228790SPeter Avalos  */
47*f4228790SPeter Avalos time_t
48*f4228790SPeter Avalos _time64_to_time(__int64_t t64)
49*f4228790SPeter Avalos {
50*f4228790SPeter Avalos 
51*f4228790SPeter Avalos 	return((time_t)t64);
52*f4228790SPeter Avalos }
53*f4228790SPeter Avalos 
54*f4228790SPeter Avalos /*
55*f4228790SPeter Avalos  * Convert time_t to a 64 bit representation.  If time_t is represented
56*f4228790SPeter Avalos  * as 32 bits we simply sign-extend and do not support times past 2038.
57*f4228790SPeter Avalos  */
58*f4228790SPeter Avalos __int64_t
59*f4228790SPeter Avalos _time_to_time64(time_t t)
60*f4228790SPeter Avalos {
61*f4228790SPeter Avalos 
62*f4228790SPeter Avalos 	return((__int64_t)t);
63*f4228790SPeter Avalos }
64*f4228790SPeter Avalos 
65*f4228790SPeter Avalos /*
66*f4228790SPeter Avalos  * Convert to/from 'long'.  Depending on the sizeof(long) this may or
67*f4228790SPeter Avalos  * may not require using the 50-year rule.
68*f4228790SPeter Avalos  */
69*f4228790SPeter Avalos long
70*f4228790SPeter Avalos _time_to_long(time_t t)
71*f4228790SPeter Avalos {
72*f4228790SPeter Avalos 
73*f4228790SPeter Avalos 	if (sizeof(long) == sizeof(__int64_t))
74*f4228790SPeter Avalos 		return(_time_to_time64(t));
75*f4228790SPeter Avalos 	return((long)t);
76*f4228790SPeter Avalos }
77*f4228790SPeter Avalos 
78*f4228790SPeter Avalos time_t
79*f4228790SPeter Avalos _long_to_time(long tlong)
80*f4228790SPeter Avalos {
81*f4228790SPeter Avalos 
82*f4228790SPeter Avalos 	if (sizeof(long) == sizeof(__int32_t))
83*f4228790SPeter Avalos 		return(_time32_to_time(tlong));
84*f4228790SPeter Avalos 	return((time_t)tlong);
85*f4228790SPeter Avalos }
86*f4228790SPeter Avalos 
87*f4228790SPeter Avalos /*
88*f4228790SPeter Avalos  * Convert to/from 'int'.  Depending on the sizeof(int) this may or
89*f4228790SPeter Avalos  * may not require using the 50-year rule.
90*f4228790SPeter Avalos  */
91*f4228790SPeter Avalos int
92*f4228790SPeter Avalos _time_to_int(time_t t)
93*f4228790SPeter Avalos {
94*f4228790SPeter Avalos 
95*f4228790SPeter Avalos 	if (sizeof(int) == sizeof(__int64_t))
96*f4228790SPeter Avalos 		return(_time_to_time64(t));
97*f4228790SPeter Avalos 	return((int)t);
98*f4228790SPeter Avalos }
99*f4228790SPeter Avalos 
100*f4228790SPeter Avalos time_t
101*f4228790SPeter Avalos _int_to_time(int tint)
102*f4228790SPeter Avalos {
103*f4228790SPeter Avalos 
104*f4228790SPeter Avalos 	if (sizeof(int) == sizeof(__int32_t))
105*f4228790SPeter Avalos 		return(_time32_to_time(tint));
106*f4228790SPeter Avalos 	return((time_t)tint);
107*f4228790SPeter Avalos }
108