1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
|
/*
* This routine converts time as follows.
* The epoch is 0000 Jan 1 1970 GMT.
* The argument time is in seconds since then.
* The localtime(t) entry returns a pointer to an array
* containing
*
* seconds (0-59)
* minutes (0-59)
* hours (0-23)
* day of month (1-31)
* month (0-11)
* year-1970
* weekday (0-6, Sun is 0)
* day of the year
* daylight savings flag
*
* The routine gets the daylight savings time from the environment.
*
* asctime(tvec))
* where tvec is produced by localtime
* returns a ptr to a character string
* that has the ascii time in the form
*
* \\
* Thu Jan 01 00:00:00 GMT 1970n0
* 012345678901234567890123456789
* 0 1 2
*
* ctime(t) just calls localtime, then asctime.
*/
#include <u.h>
#include <libc.h>
#include "zoneinfo.h"
static char dmsize[12] =
{
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
#define dysize ctimedysize
static int dysize(int);
static void ct_numb(char*, int);
char*
ctime(long t)
{
return asctime(localtime(t));
}
Tm*
localtime(long tim)
{
Tinfo ti;
Tm *ct;
if (zonelookuptinfo(&ti, tim)!=-1) {
ct = gmtime(tim+ti.tzoff);
strncpy(ct->zone, ti.zone, sizeof ct->zone);
ct->zone[sizeof ct->zone-1] = 0;
ct->tzoff = ti.tzoff;
return ct;
}
return gmtime(tim);
}
Tm*
gmtime(long tim)
{
int d0, d1;
long hms, day;
static Tm xtime;
/*
* break initial number into days
*/
hms = tim % 86400L;
day = tim / 86400L;
if(hms < 0) {
hms += 86400L;
day -= 1;
}
/*
* generate hours:minutes:seconds
*/
xtime.sec = hms % 60;
d1 = hms / 60;
xtime.min = d1 % 60;
d1 /= 60;
xtime.hour = d1;
/*
* day is the day number.
* generate day of the week.
* The addend is 4 mod 7 (1/1/1970 was Thursday)
*/
xtime.wday = (day + 7340036L) % 7;
/*
* year number
*/
if(day >= 0)
for(d1 = 1970; day >= dysize(d1); d1++)
day -= dysize(d1);
else
for (d1 = 1970; day < 0; d1--)
day += dysize(d1-1);
xtime.year = d1-1900;
xtime.yday = d0 = day;
/*
* generate month
*/
if(dysize(d1) == 366)
dmsize[1] = 29;
for(d1 = 0; d0 >= dmsize[d1]; d1++)
d0 -= dmsize[d1];
dmsize[1] = 28;
xtime.mday = d0 + 1;
xtime.mon = d1;
strcpy(xtime.zone, "GMT");
return &xtime;
}
char*
asctime(Tm *t)
{
char *ncp;
static char cbuf[30];
strcpy(cbuf, "Thu Jan 01 00:00:00 GMT 1970\n");
ncp = &"SunMonTueWedThuFriSat"[t->wday*3];
cbuf[0] = *ncp++;
cbuf[1] = *ncp++;
cbuf[2] = *ncp;
ncp = &"JanFebMarAprMayJunJulAugSepOctNovDec"[t->mon*3];
cbuf[4] = *ncp++;
cbuf[5] = *ncp++;
cbuf[6] = *ncp;
ct_numb(cbuf+8, t->mday);
ct_numb(cbuf+11, t->hour+100);
ct_numb(cbuf+14, t->min+100);
ct_numb(cbuf+17, t->sec+100);
ncp = t->zone;
cbuf[20] = *ncp++;
cbuf[21] = *ncp++;
cbuf[22] = *ncp;
if(t->year >= 100) {
cbuf[24] = '2';
cbuf[25] = '0';
}
ct_numb(cbuf+26, t->year+100);
return cbuf;
}
static
int
dysize(int y)
{
if(y%4 == 0 && (y%100 != 0 || y%400 == 0))
return 366;
return 365;
}
static
void
ct_numb(char *cp, int n)
{
cp[0] = ' ';
if(n >= 10)
cp[0] = (n/10)%10 + '0';
cp[1] = n%10 + '0';
}
|
