1 /*
2 * Copyright (c) 2006-2018, RT-Thread Development Team
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 *
6 * Change Logs:
7 * Date Author Notes
8 * 2018-10-26 zylx first version
9 */
10
11 #if defined(__CC_ARM) || defined(__CLANG_ARM) || defined (__IAR_SYSTEMS_ICC__)
12 #include <sys/time.h>
13
14 /* seconds per day */
15 #define SPD 24*60*60
16
17 /* days per month -- nonleap! */
18 const short __spm[13] =
19 {
20 0,
21 (31),
22 (31 + 28),
23 (31 + 28 + 31),
24 (31 + 28 + 31 + 30),
25 (31 + 28 + 31 + 30 + 31),
26 (31 + 28 + 31 + 30 + 31 + 30),
27 (31 + 28 + 31 + 30 + 31 + 30 + 31),
28 (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31),
29 (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30),
30 (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31),
31 (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30),
32 (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30 + 31),
33 };
34
__isleap(int year)35 int __isleap(int year)
36 {
37 /* every fourth year is a leap year except for century years that are
38 * not divisible by 400. */
39 /* return (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)); */
40 return (!(year % 4) && ((year % 100) || !(year % 400)));
41 }
42
43 /**
44 * This function will convert Time (Restartable)
45 *
46 * @param timep the timestamp
47 * @param the structure to stores information
48 *
49 * @return the structure to stores information
50 *
51 */
gmtime_r(const time_t * timep,struct tm * r)52 struct tm *gmtime_r(const time_t *timep, struct tm *r)
53 {
54 time_t i;
55 register time_t work = *timep % (SPD);
56 r->tm_sec = work % 60;
57 work /= 60;
58 r->tm_min = work % 60;
59 r->tm_hour = work / 60;
60 work = *timep / (SPD);
61 r->tm_wday = (4 + work) % 7;
62 for (i = 1970;; ++i)
63 {
64 register time_t k = __isleap(i) ? 366 : 365;
65 if (work >= k)
66 work -= k;
67 else
68 break;
69 }
70 r->tm_year = i - 1900;
71 r->tm_yday = work;
72
73 r->tm_mday = 1;
74 if (__isleap(i) && (work > 58))
75 {
76 if (work == 59)
77 r->tm_mday = 2; /* 29.2. */
78 work -= 1;
79 }
80
81 for (i = 11; i && (__spm[i] > work); --i)
82 ;
83 r->tm_mon = i;
84 r->tm_mday += work - __spm[i];
85 return r;
86 }
87 #endif /* end of __CC_ARM or __CLANG_ARM or __IAR_SYSTEMS_ICC__ */
88
89