1 /* date.c - set/get the date
2 *
3 * Copyright 2012 Andre Renaud <andre@bluewatersys.com>
4 *
5 * See http://opengroup.org/onlinepubs/9699919799/utilities/date.html
6 *
7 * Note: setting a 2 year date is 50 years back/forward from today,
8 * not posix's hardwired magic dates.
9
10 USE_DATE(NEWTOY(date, "d:s:r:u[!dr]", TOYFLAG_BIN))
11
12 config DATE
13 bool "date"
14 default y
15 help
16 usage: date [-u] [-r FILE] [-d DATE] [+DISPLAY_FORMAT] [-s SET_FORMAT] [SET]
17
18 Set/get the current date/time. With no SET shows the current date.
19
20 Default SET format is "MMDDhhmm[[CC]YY][.ss]", that's (2 digits each)
21 month, day, hour (0-23), and minute. Optionally century, year, and second.
22
23 -d Show DATE instead of current time (convert date format)
24 -r Use modification time of FILE instead of current date
25 -s +FORMAT for SET or -d (instead of MMDDhhmm[[CC]YY][.ss])
26 -u Use UTC instead of current timezone
27
28 +FORMAT specifies display format string using these escapes:
29
30 %% literal % %n newline %t tab
31 %S seconds (00-60) %M minute (00-59) %m month (01-12)
32 %H hour (0-23) %I hour (01-12) %p AM/PM
33 %y short year (00-99) %Y year %C century
34 %a short weekday name %A weekday name %u day of week (1-7, 1=mon)
35 %b short month name %B month name %Z timezone name
36 %j day of year (001-366) %d day of month (01-31) %e day of month ( 1-31)
37
38 %U Week of year (0-53 start sunday) %W Week of year (0-53 start monday)
39 %V Week of year (1-53 start monday, week < 4 days not part of this year)
40
41 %D = "%m/%d/%y" %r = "%I : %M : %S %p" %T = "%H:%M:%S" %h = "%b"
42 %x locale date %X locale time %c locale date/time
43 */
44
45 #define FOR_date
46 #include "toys.h"
47
GLOBALS(char * file;char * setfmt;char * showdate;)48 GLOBALS(
49 char *file;
50 char *setfmt;
51 char *showdate;
52 )
53
54 // Handle default posix date format: mmddhhmm[[cc]yy]
55 // returns 0 success, nonzero for error
56 int parse_posixdate(char *str, struct tm *tm)
57 {
58 int len;
59
60 len = 0;
61 sscanf(str, "%2u%2u%2u%2u%n", &tm->tm_mon, &tm->tm_mday, &tm->tm_hour,
62 &tm->tm_min, &len);
63 if (len != 8) return 1;
64 str += len;
65 tm->tm_mon--;
66
67 // If year specified, overwrite one we fetched earlier
68 if (*str && *str != '.') {
69 unsigned year, r1 = tm->tm_year % 100, r2 = (tm->tm_year + 50) % 100,
70 century = tm->tm_year - r1;
71
72 len = 0;
73 sscanf(str, "%u%n", &year, &len);
74 if (len == 4) year -= 1900;
75 else if (len != 2) return 1;
76 str += len;
77
78 // 2 digit years, next 50 years are "future", last 50 years are "past".
79 // A "future" date in past is a century ahead.
80 // A non-future date in the future is a century behind.
81 if ((r1 < r2) ? (r1 < year && year < r2) : (year < r1 || year > r2)) {
82 if (year < r1) year += 100;
83 } else if (year > r1) year -= 100;
84 tm->tm_year = year + century;
85 }
86 if (*str == '.') {
87 len = 0;
88 sscanf(str, ".%u%n", &tm->tm_sec, &len);
89 str += len;
90 }
91
92 return *str;
93 }
94
date_main(void)95 void date_main(void)
96 {
97 char *setdate = *toys.optargs, *format_string = "%a %b %e %H:%M:%S %Z %Y",
98 *tz = 0;
99 struct tm tm;
100
101 // We can't just pass a timezone to mktime because posix.
102 if (toys.optflags & FLAG_u) {
103 if (CFG_TOYBOX_FREE) tz = getenv("TZ");
104 setenv("TZ", "UTC", 1);
105 tzset();
106 }
107
108 if (TT.showdate) {
109 setdate = TT.showdate;
110 if (TT.setfmt) {
111 char *s = strptime(TT.showdate, TT.setfmt+(*TT.setfmt=='+'), &tm);
112
113 if (!s || *s) goto bad_date;
114 } else if (parse_posixdate(TT.showdate, &tm)) goto bad_date;
115 } else {
116 time_t now;
117
118 if (TT.file) {
119 struct stat st;
120
121 xstat(TT.file, &st);
122 now = st.st_mtim.tv_sec;
123 } else now = time(0);
124
125 ((toys.optflags & FLAG_u) ? gmtime_r : localtime_r)(&now, &tm);
126 }
127
128 setdate = *toys.optargs;
129 // Fall through if no arguments
130 if (!setdate);
131 // Display the date?
132 else if (*setdate == '+') {
133 format_string = toys.optargs[0]+1;
134 setdate = toys.optargs[1];
135
136 // Set the date
137 } else if (setdate) {
138 struct timeval tv;
139
140 if (parse_posixdate(setdate, &tm)) goto bad_date;
141
142 if (toys.optflags & FLAG_u) {
143 char *tz = CFG_TOYBOX_FREE ? getenv("TZ") : 0;
144
145 // We can't just pass a timezone to mktime because posix.
146 setenv("TZ", "UTC", 1);
147 tzset();
148 tv.tv_sec = mktime(&tm);
149 if (CFG_TOYBOX_FREE) {
150 if (tz) setenv("TZ", tz, 1);
151 else unsetenv("TZ");
152 tzset();
153 }
154 } else tv.tv_sec = mktime(&tm);
155 if (tv.tv_sec == (time_t)-1) goto bad_date;
156
157 tv.tv_usec = 0;
158 if (settimeofday(&tv, NULL) < 0) perror_msg("cannot set date");
159 }
160
161 if (toys.optflags & FLAG_u) {
162 if (tz) setenv("TZ", tz, 1);
163 else unsetenv("TZ");
164 tzset();
165 }
166
167 if (!strftime(toybuf, sizeof(toybuf), format_string, &tm))
168 perror_exit("bad format '%s'", format_string);
169 puts(toybuf);
170
171 return;
172
173 bad_date:
174 error_exit("bad date '%s'", setdate);
175 }
176