xref: /freebsd/lib/libc/stdtime/time32.c (revision 559a218c)
1237c4e3aSMatthew Dillon /*-
2237c4e3aSMatthew Dillon  * Copyright (c) 2001 FreeBSD Inc.
3237c4e3aSMatthew Dillon  * All rights reserved.
4237c4e3aSMatthew Dillon  *
5237c4e3aSMatthew Dillon  * These routines are for converting time_t to fixed-bit representations
6237c4e3aSMatthew Dillon  * for use in protocols or storage.  When converting time to a larger
7237c4e3aSMatthew Dillon  * representation of time_t these routines are expected to assume temporal
8237c4e3aSMatthew Dillon  * locality and use the 50-year rule to properly set the msb bits.  XXX
9237c4e3aSMatthew Dillon  *
10237c4e3aSMatthew Dillon  * Redistribution and use under the terms of the COPYRIGHT file at the
11237c4e3aSMatthew Dillon  * base of the source tree.
12237c4e3aSMatthew Dillon  */
13237c4e3aSMatthew Dillon 
14237c4e3aSMatthew Dillon #include <sys/types.h>
158466ae90SGarrett Wollman #include <timeconv.h>
16237c4e3aSMatthew Dillon 
17237c4e3aSMatthew Dillon /*
18237c4e3aSMatthew Dillon  * Convert a 32 bit representation of time_t into time_t.  XXX needs to
19237c4e3aSMatthew Dillon  * implement the 50-year rule to handle post-2038 conversions.
20237c4e3aSMatthew Dillon  */
21237c4e3aSMatthew Dillon time_t
_time32_to_time(__int32_t t32)22170ac683SMatthew Dillon _time32_to_time(__int32_t t32)
23237c4e3aSMatthew Dillon {
24237c4e3aSMatthew Dillon     return((time_t)t32);
25237c4e3aSMatthew Dillon }
26237c4e3aSMatthew Dillon 
27237c4e3aSMatthew Dillon /*
28237c4e3aSMatthew Dillon  * Convert time_t to a 32 bit representation.  If time_t is 64 bits we can
29237c4e3aSMatthew Dillon  * simply chop it down.   The resulting 32 bit representation can be
30237c4e3aSMatthew Dillon  * converted back to a temporally local 64 bit time_t using time32_to_time.
31237c4e3aSMatthew Dillon  */
32237c4e3aSMatthew Dillon __int32_t
_time_to_time32(time_t t)33170ac683SMatthew Dillon _time_to_time32(time_t t)
34237c4e3aSMatthew Dillon {
35237c4e3aSMatthew Dillon     return((__int32_t)t);
36237c4e3aSMatthew Dillon }
37237c4e3aSMatthew Dillon 
38237c4e3aSMatthew Dillon /*
39237c4e3aSMatthew Dillon  * Convert a 64 bit representation of time_t into time_t.  If time_t is
40237c4e3aSMatthew Dillon  * represented as 32 bits we can simply chop it and not support times
41237c4e3aSMatthew Dillon  * past 2038.
42237c4e3aSMatthew Dillon  */
43237c4e3aSMatthew Dillon time_t
_time64_to_time(__int64_t t64)44170ac683SMatthew Dillon _time64_to_time(__int64_t t64)
45237c4e3aSMatthew Dillon {
46237c4e3aSMatthew Dillon     return((time_t)t64);
47237c4e3aSMatthew Dillon }
48237c4e3aSMatthew Dillon 
49237c4e3aSMatthew Dillon /*
50237c4e3aSMatthew Dillon  * Convert time_t to a 64 bit representation.  If time_t is represented
51237c4e3aSMatthew Dillon  * as 32 bits we simply sign-extend and do not support times past 2038.
52237c4e3aSMatthew Dillon  */
53237c4e3aSMatthew Dillon __int64_t
_time_to_time64(time_t t)54170ac683SMatthew Dillon _time_to_time64(time_t t)
55237c4e3aSMatthew Dillon {
56237c4e3aSMatthew Dillon     return((__int64_t)t);
57237c4e3aSMatthew Dillon }
58237c4e3aSMatthew Dillon 
59e8627df6SMatthew Dillon /*
60e8627df6SMatthew Dillon  * Convert to/from 'long'.  Depending on the sizeof(long) this may or
61e8627df6SMatthew Dillon  * may not require using the 50-year rule.
62e8627df6SMatthew Dillon  */
63e8627df6SMatthew Dillon long
_time_to_long(time_t t)64170ac683SMatthew Dillon _time_to_long(time_t t)
65e8627df6SMatthew Dillon {
66e8627df6SMatthew Dillon     if (sizeof(long) == sizeof(__int64_t))
67170ac683SMatthew Dillon 	return(_time_to_time64(t));
68e8627df6SMatthew Dillon     return((long)t);
69e8627df6SMatthew Dillon }
70e8627df6SMatthew Dillon 
71e8627df6SMatthew Dillon time_t
_long_to_time(long tlong)72170ac683SMatthew Dillon _long_to_time(long tlong)
73e8627df6SMatthew Dillon {
74e8627df6SMatthew Dillon     if (sizeof(long) == sizeof(__int32_t))
75170ac683SMatthew Dillon 	return(_time32_to_time(tlong));
76e8627df6SMatthew Dillon     return((time_t)tlong);
77e8627df6SMatthew Dillon }
78e8627df6SMatthew Dillon 
79e8627df6SMatthew Dillon /*
80e8627df6SMatthew Dillon  * Convert to/from 'int'.  Depending on the sizeof(int) this may or
81e8627df6SMatthew Dillon  * may not require using the 50-year rule.
82e8627df6SMatthew Dillon  */
83e8627df6SMatthew Dillon int
_time_to_int(time_t t)84170ac683SMatthew Dillon _time_to_int(time_t t)
85e8627df6SMatthew Dillon {
86e8627df6SMatthew Dillon     if (sizeof(int) == sizeof(__int64_t))
87170ac683SMatthew Dillon 	return(_time_to_time64(t));
88e8627df6SMatthew Dillon     return((int)t);
89e8627df6SMatthew Dillon }
90e8627df6SMatthew Dillon 
91e8627df6SMatthew Dillon time_t
_int_to_time(int tint)92170ac683SMatthew Dillon _int_to_time(int tint)
93e8627df6SMatthew Dillon {
94e8627df6SMatthew Dillon     if (sizeof(int) == sizeof(__int32_t))
95170ac683SMatthew Dillon 	return(_time32_to_time(tint));
96e8627df6SMatthew Dillon     return((time_t)tint);
97e8627df6SMatthew Dillon }
98