xref: /nrf52832-nimble/rt-thread/components/libc/compilers/minilibc/time.c (revision 042d53a763ad75cb1465103098bb88c245d95138)
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  */
9 #include <time.h>
10 #include <rtthread.h>
11 
12 /* days per month -- nonleap! */
13 const short __spm[13] =
14   { 0,
15     (31),
16     (31+28),
17     (31+28+31),
18     (31+28+31+30),
19     (31+28+31+30+31),
20     (31+28+31+30+31+30),
21     (31+28+31+30+31+30+31),
22     (31+28+31+30+31+30+31+31),
23     (31+28+31+30+31+30+31+31+30),
24     (31+28+31+30+31+30+31+31+30+31),
25     (31+28+31+30+31+30+31+31+30+31+30),
26     (31+28+31+30+31+30+31+31+30+31+30+31),
27   };
28 static long int timezone;
29 static const char days[] = "Sun Mon Tue Wed Thu Fri Sat ";
30 static const char months[] = "Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ";
31 
32 /* seconds per day */
33 #define SPD 24*60*60
34 
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 struct tm *gmtime_r(const time_t *timep, struct tm *r)
44 {
45 	time_t i;
46 	register time_t work = *timep % (SPD);
47 	r->tm_sec = work % 60;
48 	work /= 60;
49 	r->tm_min = work % 60;
50 	r->tm_hour = work / 60;
51 	work = *timep / (SPD);
52 	r->tm_wday = (4 + work) % 7;
53 	for (i = 1970;; ++i)
54 	{
55 		register time_t k = __isleap(i) ? 366 : 365;
56 		if (work >= k)
57 			work -= k;
58 		else
59 			break;
60 	}
61 	r->tm_year = i - 1900;
62 	r->tm_yday = work;
63 
64 	r->tm_mday = 1;
65 	if (__isleap(i) && (work > 58))
66 	{
67 		if (work == 59)
68 			r->tm_mday = 2; /* 29.2. */
69 		work -= 1;
70 	}
71 
72 	for (i = 11; i && (__spm[i] > work); --i)
73 		;
74 	r->tm_mon = i;
75 	r->tm_mday += work - __spm[i];
76 	return r;
77 }
78 
79 struct tm* localtime_r(const time_t* t, struct tm* r)
80 {
81 	time_t tmp;
82 	struct timezone tz = {0};
83 	gettimeofday(0, &tz);
84 	timezone = tz.tz_minuteswest * 60L;
85 	tmp = *t + timezone;
86 	return gmtime_r(&tmp, r);
87 }
88 
89 struct tm* localtime(const time_t* t)
90 {
91 	static struct tm tmp;
92 	return localtime_r(t, &tmp);
93 }
94 
95 time_t mktime(struct tm * const t)
96 {
97 	register time_t day;
98 	register time_t i;
99 	register time_t years = t->tm_year - 70;
100 
101 	if (t->tm_sec > 60)
102 	{
103 		t->tm_min += t->tm_sec / 60;
104 		t->tm_sec %= 60;
105 	}
106 	if (t->tm_min > 60)
107 	{
108 		t->tm_hour += t->tm_min / 60;
109 		t->tm_min %= 60;
110 	}
111 	if (t->tm_hour > 24)
112 	{
113 		t->tm_mday += t->tm_hour / 24;
114 		t->tm_hour %= 24;
115 	}
116 	if (t->tm_mon > 12)
117 	{
118 		t->tm_year += t->tm_mon / 12;
119 		t->tm_mon %= 12;
120 	}
121 	while (t->tm_mday > __spm[1 + t->tm_mon])
122 	{
123 		if (t->tm_mon == 1 && __isleap(t->tm_year + 1900))
124 		{
125 			--t->tm_mday;
126 		}
127 		t->tm_mday -= __spm[t->tm_mon];
128 		++t->tm_mon;
129 		if (t->tm_mon > 11)
130 		{
131 			t->tm_mon = 0;
132 			++t->tm_year;
133 		}
134 	}
135 
136 	if (t->tm_year < 70)
137 		return (time_t) -1;
138 
139 	/* Days since 1970 is 365 * number of years + number of leap years since 1970 */
140 	day = years * 365 + (years + 1) / 4;
141 
142 	/* After 2100 we have to substract 3 leap years for every 400 years
143 	 This is not intuitive. Most mktime implementations do not support
144 	 dates after 2059, anyway, so we might leave this out for it's
145 	 bloat. */
146 	if (years >= 131)
147 	{
148 		years -= 131;
149 		years /= 100;
150 		day -= (years >> 2) * 3 + 1;
151 		if ((years &= 3) == 3)
152 			years--;
153 		day -= years;
154 	}
155 
156 	day += t->tm_yday = __spm[t->tm_mon] + t->tm_mday - 1 +
157 			(__isleap(t->tm_year + 1900) & (t->tm_mon > 1));
158 
159 	/* day is now the number of days since 'Jan 1 1970' */
160 	i = 7;
161 	t->tm_wday = (day + 4) % i; /* Sunday=0, Monday=1, ..., Saturday=6 */
162 
163 	i = 24;
164 	day *= i;
165 	i = 60;
166 	return ((day + t->tm_hour) * i + t->tm_min) * i + t->tm_sec;
167 }
168 
169 static void num2str(char *c, int i)
170 {
171 	c[0] = i / 10 + '0';
172 	c[1] = i % 10 + '0';
173 }
174 
175 char *asctime_r(const struct tm *t, char *buf)
176 {
177 	/* "Wed Jun 30 21:49:08 1993\n" */
178 	*(int*) buf = *(int*) (days + (t->tm_wday << 2));
179 	*(int*) (buf + 4) = *(int*) (months + (t->tm_mon << 2));
180 	num2str(buf + 8, t->tm_mday);
181 	if (buf[8] == '0')
182 		buf[8] = ' ';
183 	buf[10] = ' ';
184 	num2str(buf + 11, t->tm_hour);
185 	buf[13] = ':';
186 	num2str(buf + 14, t->tm_min);
187 	buf[16] = ':';
188 	num2str(buf + 17, t->tm_sec);
189 	buf[19] = ' ';
190 	num2str(buf + 20, (t->tm_year + 1900) / 100);
191 	num2str(buf + 22, (t->tm_year + 1900) % 100);
192 	buf[24] = '\n';
193 	return buf;
194 }
195 
196 char *asctime(const struct tm *timeptr)
197 {
198 	static char buf[25];
199 	return asctime_r(timeptr, buf);
200 }
201 
202 char *ctime(const time_t *timep)
203 {
204 	return asctime(localtime(timep));
205 }
206 
207 #ifdef RT_USING_DEVICE
208 int gettimeofday(struct timeval *tp, void *ignore)
209 {
210 	time_t time;
211 	rt_device_t device;
212 
213 	device = rt_device_find("rtc");
214 	if (device != RT_NULL)
215 	{
216 		rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time);
217 		if (tp != RT_NULL)
218 		{
219 			tp->tv_sec = time;
220 			tp->tv_usec = 0;
221 		}
222 
223 		return time;
224 	}
225 
226 	return 0;
227 }
228 #endif
229 
230 #ifndef _gettimeofday
231 /* Dummy function when hardware do not have RTC */
232 int _gettimeofday( struct timeval *tv, void *ignore)
233 {
234     tv->tv_sec = 0;  // convert to seconds
235     tv->tv_usec = 0;  // get remaining microseconds
236     return 0;  // return non-zero for error
237 }
238 #endif
239 
240 /**
241  * Returns the current time.
242  *
243  * @param time_t * t the timestamp pointer, if not used, keep NULL.
244  *
245  * @return time_t return timestamp current.
246  *
247  */
248 /* for IAR 6.2 later Compiler */
249 #if defined (__IAR_SYSTEMS_ICC__) &&  (__VER__) >= 6020000
250 #pragma module_name = "?time"
251 time_t (__time32)(time_t *t) /* Only supports 32-bit timestamp */
252 #else
253 time_t time(time_t *t)
254 #endif
255 {
256     time_t time_now = 0;
257 
258 #ifdef RT_USING_RTC
259     static rt_device_t device = RT_NULL;
260 
261     /* optimization: find rtc device only first. */
262     if (device == RT_NULL)
263     {
264         device = rt_device_find("rtc");
265     }
266 
267     /* read timestamp from RTC device. */
268     if (device != RT_NULL)
269     {
270         if (rt_device_open(device, 0) == RT_EOK)
271         {
272             rt_device_control(device, RT_DEVICE_CTRL_RTC_GET_TIME, &time_now);
273             rt_device_close(device);
274         }
275     }
276 #endif /* RT_USING_RTC */
277 
278     /* if t is not NULL, write timestamp to *t */
279     if (t != RT_NULL)
280     {
281         *t = time_now;
282     }
283 
284     return time_now;
285 }
286 
287 RT_WEAK clock_t clock(void)
288 {
289     return rt_tick_get();
290 }
291