File: date.c

package info (click to toggle)
busybox 1:1.17.1-8+deb6u11
  • links: PTS
  • area: main
  • in suites: squeeze-lts
  • size: 15,608 kB
  • ctags: 26,465
  • sloc: ansic: 182,252; sh: 6,047; cpp: 1,428; makefile: 1,031; yacc: 570; lex: 355; perl: 309; python: 251; awk: 29
file content (334 lines) | stat: -rw-r--r-- 9,602 bytes parent folder | download | duplicates (2)
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
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
/* vi: set sw=4 ts=4: */
/*
 * Mini date implementation for busybox
 *
 * by Matthew Grant <grantma@anathoth.gen.nz>
 *
 * iso-format handling added by Robert Griebl <griebl@gmx.de>
 * bugfixes and cleanup by Bernhard Reutner-Fischer
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/

/* This 'date' command supports only 2 time setting formats,
   all the GNU strftime stuff (its in libc, lets use it),
   setting time using UTC and displaying it, as well as
   an RFC 2822 compliant date output for shell scripting
   mail commands */

/* Input parsing code is always bulky - used heavy duty libc stuff as
   much as possible, missed out a lot of bounds checking */

/* Default input handling to save surprising some people */

/* GNU coreutils 6.9 man page:
 * date [OPTION]... [+FORMAT]
 * date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]
 * -d, --date=STRING
 *      display time described by STRING, not `now'
 * -f, --file=DATEFILE
 *      like --date once for each line of DATEFILE
 * -r, --reference=FILE
 *      display the last modification time of FILE
 * -R, --rfc-2822
 *      output date and time in RFC 2822 format.
 *      Example: Mon, 07 Aug 2006 12:34:56 -0600
 * --rfc-3339=TIMESPEC
 *      output date and time in RFC 3339 format.
 *      TIMESPEC='date', 'seconds', or 'ns'
 *      Date and time components are separated by a single space:
 *      2006-08-07 12:34:56-06:00
 * -s, --set=STRING
 *      set time described by STRING
 * -u, --utc, --universal
 *      print or set Coordinated Universal Time
 *
 * Busybox:
 * long options are not supported
 * -f is not supported
 * -I seems to roughly match --rfc-3339, but -I has _optional_ param
 *    (thus "-I seconds" doesn't work, only "-Iseconds"),
 *    and does not support -Ins
 * -D FMT is a bbox extension for _input_ conversion of -d DATE
 */

//kbuild:lib-$(CONFIG_DATE) += date.o

//config:config DATE
//config:	bool "date"
//config:	default y
//config:	help
//config:	  date is used to set the system date or display the
//config:	  current time in the given format.
//config:
//config:config FEATURE_DATE_ISOFMT
//config:	bool "Enable ISO date format output (-I)"
//config:	default y
//config:	depends on DATE
//config:	help
//config:	  Enable option (-I) to output an ISO-8601 compliant
//config:	  date/time string.
//config:
//config:config FEATURE_DATE_NANO
//config:	bool "Support %[num]N nanosecond format specifier"
//config:	default n
//config:	depends on DATE && PLATFORM_LINUX # syscall(__NR_clock_gettime)
//config:	help
//config:	  Support %[num]N format specifier. Adds ~250 bytes of code.
//config:
//config:config FEATURE_DATE_COMPAT
//config:	bool "Support weird 'date MMDDhhmm[[YY]YY][.ss]' format"
//config:	default y
//config:	depends on DATE
//config:	help
//config:	  System time can be set by 'date -s DATE' and simply 'date DATE',
//config:	  but formats of DATE string are different. 'date DATE' accepts
//config:	  a rather weird MMDDhhmm[[YY]YY][.ss] format with completely
//config:	  unnatural placement of year between minutes and seconds.
//config:	  date -s (and other commands like touch -d) use more sensible
//config:	  formats (for one, ISO format YYYY-MM-DD hh:mm:ss.ssssss).
//config:
//config:	  With this option off, 'date DATE' is 'date -s DATE' support
//config:	  the same format. With it on, 'date DATE' additionally supports
//config:	  MMDDhhmm[[YY]YY][.ss] format.

#include "libbb.h"
#if ENABLE_FEATURE_DATE_NANO
# include <sys/syscall.h>
#endif

enum {
	OPT_RFC2822   = (1 << 0), /* R */
	OPT_SET       = (1 << 1), /* s */
	OPT_UTC       = (1 << 2), /* u */
	OPT_DATE      = (1 << 3), /* d */
	OPT_REFERENCE = (1 << 4), /* r */
	OPT_TIMESPEC  = (1 << 5) * ENABLE_FEATURE_DATE_ISOFMT, /* I */
	OPT_HINT      = (1 << 6) * ENABLE_FEATURE_DATE_ISOFMT, /* D */
};

static void maybe_set_utc(int opt)
{
	if (opt & OPT_UTC)
		putenv((char*)"TZ=UTC0");
}

#if ENABLE_LONG_OPTS
static const char date_longopts[] ALIGN1 =
		"rfc-822\0"   No_argument       "R"
		"rfc-2822\0"  No_argument       "R"
		"set\0"       Required_argument "s"
		"utc\0"       No_argument       "u"
	/*	"universal\0" No_argument       "u" */
		"date\0"      Required_argument "d"
		"reference\0" Required_argument "r"
		;
#endif

int date_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int date_main(int argc UNUSED_PARAM, char **argv)
{
	struct timespec ts;
	struct tm tm_time;
	char buf_fmt_dt2str[64];
	unsigned opt;
	int ifmt = -1;
	char *date_str;
	char *fmt_dt2str;
	char *fmt_str2dt;
	char *filename;
	char *isofmt_arg = NULL;

	opt_complementary = "d--s:s--d"
		IF_FEATURE_DATE_ISOFMT(":R--I:I--R");
	IF_LONG_OPTS(applet_long_options = date_longopts;)
	opt = getopt32(argv, "Rs:ud:r:"
			IF_FEATURE_DATE_ISOFMT("I::D:"),
			&date_str, &date_str, &filename
			IF_FEATURE_DATE_ISOFMT(, &isofmt_arg, &fmt_str2dt));
	argv += optind;
	maybe_set_utc(opt);

	if (ENABLE_FEATURE_DATE_ISOFMT && (opt & OPT_TIMESPEC)) {
		ifmt = 0; /* default is date */
		if (isofmt_arg) {
			static const char isoformats[] ALIGN1 =
				"date\0""hours\0""minutes\0""seconds\0"; /* ns? */
			ifmt = index_in_substrings(isoformats, isofmt_arg);
			if (ifmt < 0)
				bb_show_usage();
		}
	}

	fmt_dt2str = NULL;
	if (argv[0] && argv[0][0] == '+') {
		fmt_dt2str = &argv[0][1]; /* skip over the '+' */
		argv++;
	}
	if (!(opt & (OPT_SET | OPT_DATE))) {
		opt |= OPT_SET;
		date_str = argv[0]; /* can be NULL */
		if (date_str) {
#if ENABLE_FEATURE_DATE_COMPAT
			int len = strspn(date_str, "0123456789");
			if (date_str[len] == '\0'
			 || (date_str[len] == '.'
			    && isdigit(date_str[len+1])
			    && isdigit(date_str[len+2])
			    && date_str[len+3] == '\0'
			    )
			) {
				/* Dreaded MMDDhhmm[[CC]YY][.ss] format!
				 * It does not match -d or -s format.
				 * Some users actually do use it.
				 */
				len -= 8;
				if (len < 0 || len > 4 || (len & 1))
					bb_error_msg_and_die(bb_msg_invalid_date, date_str);
				if (len != 0) { /* move YY or CCYY to front */
					char buf[4];
					memcpy(buf, date_str + 8, len);
					memmove(date_str + len, date_str, 8);
					memcpy(date_str, buf, len);
				}
			}
#endif
			argv++;
		}
	}
	if (*argv)
		bb_show_usage();

	/* Now we have parsed all the information except the date format
	 * which depends on whether the clock is being set or read */

	if (opt & OPT_REFERENCE) {
		struct stat statbuf;
		xstat(filename, &statbuf);
		ts.tv_sec = statbuf.st_mtime;
#if ENABLE_FEATURE_DATE_NANO
		ts.tv_nsec = statbuf.st_mtim.tv_nsec;
#endif
	} else {
#if ENABLE_FEATURE_DATE_NANO
		/* libc has incredibly messy way of doing this,
		 * typically requiring -lrt. We just skip all this mess */
		syscall(__NR_clock_gettime, CLOCK_REALTIME, &ts);
#else
		time(&ts.tv_sec);
#endif
	}
	localtime_r(&ts.tv_sec, &tm_time);

	/* If date string is given, update tm_time, and maybe set date */
	if (date_str != NULL) {
		/* Zero out fields - take her back to midnight! */
		tm_time.tm_sec = 0;
		tm_time.tm_min = 0;
		tm_time.tm_hour = 0;

		/* Process any date input to UNIX time since 1 Jan 1970 */
		if (ENABLE_FEATURE_DATE_ISOFMT && (opt & OPT_HINT)) {
			if (strptime(date_str, fmt_str2dt, &tm_time) == NULL)
				bb_error_msg_and_die(bb_msg_invalid_date, date_str);
		} else {
			parse_datestr(date_str, &tm_time);
		}

		/* Correct any day of week and day of year etc. fields */
		tm_time.tm_isdst = -1;	/* Be sure to recheck dst */
		ts.tv_sec = validate_tm_time(date_str, &tm_time);

		maybe_set_utc(opt);

		/* if setting time, set it */
		if ((opt & OPT_SET) && stime(&ts.tv_sec) < 0) {
			bb_perror_msg("can't set date");
		}
	}

	/* Display output */

	/* Deal with format string */
	if (fmt_dt2str == NULL) {
		int i;
		fmt_dt2str = buf_fmt_dt2str;
		if (ENABLE_FEATURE_DATE_ISOFMT && ifmt >= 0) {
			/* -I[SPEC]: 0:date 1:hours 2:minutes 3:seconds */
			strcpy(fmt_dt2str, "%Y-%m-%dT%H:%M:%S");
			i = 8 + 3 * ifmt;
			if (ifmt != 0) {
				/* TODO: if (ifmt==4) i += sprintf(&fmt_dt2str[i], ",%09u", nanoseconds); */
 format_utc:
				fmt_dt2str[i++] = '%';
				fmt_dt2str[i++] = (opt & OPT_UTC) ? 'Z' : 'z';
			}
			fmt_dt2str[i] = '\0';
		} else if (opt & OPT_RFC2822) {
			/* -R. undo busybox.c setlocale */
			if (ENABLE_LOCALE_SUPPORT)
				setlocale(LC_TIME, "C");
			strcpy(fmt_dt2str, "%a, %d %b %Y %H:%M:%S ");
			i = sizeof("%a, %d %b %Y %H:%M:%S ")-1;
			goto format_utc;
		} else { /* default case */
			fmt_dt2str = (char*)"%a %b %e %H:%M:%S %Z %Y";
		}
	}
#if ENABLE_FEATURE_DATE_NANO
	else {
		/* User-specified fmt_dt2str */
		/* Search for and process "%N" */
		char *p = fmt_dt2str;
		while ((p = strchr(p, '%')) != NULL) {
			int n, m;
			unsigned pres, scale;

			p++;
			if (*p == '%') {
				p++;
				continue;
			}
			n = strspn(p, "0123456789");
			if (p[n] != 'N') {
				p += n;
				continue;
			}
			/* We have "%[nnn]N" */
			p[-1] = '\0';
			p[n] = '\0';
			scale = 1;
			pres = 9;
			if (n) {
				pres = xatoi_u(p);
				if (pres == 0)
					pres = 9;
				m = 9 - pres;
				while (--m >= 0)
					scale *= 10;
			}

			m = p - fmt_dt2str;
			p += n + 1;
			fmt_dt2str = xasprintf("%s%0*u%s", fmt_dt2str, pres, (unsigned)ts.tv_nsec / scale, p);
			p = fmt_dt2str + m;
		}
	}
#endif

#define date_buf bb_common_bufsiz1
	if (*fmt_dt2str == '\0') {
		/* With no format string, just print a blank line */
		date_buf[0] = '\0';
	} else {
		/* Handle special conversions */
		if (strncmp(fmt_dt2str, "%f", 2) == 0) {
			fmt_dt2str = (char*)"%Y.%m.%d-%H:%M:%S";
		}
		/* Generate output string */
		strftime(date_buf, sizeof(date_buf), fmt_dt2str, &tm_time);
	}
	puts(date_buf);

	return EXIT_SUCCESS;
}