1/* vi: set sw=4 ts=4: */ 2/* 3 * Mini date implementation for busybox 4 * 5 * by Matthew Grant <grantma@anathoth.gen.nz> 6 * 7 * iso-format handling added by Robert Griebl <griebl@gmx.de> 8 * bugfixes and cleanup by Bernhard Reutner-Fischer 9 * 10 * Licensed under GPLv2 or later, see file LICENSE in this source tree. 11 */ 12/* This 'date' command supports only 2 time setting formats, 13 all the GNU strftime stuff (its in libc, lets use it), 14 setting time using UTC and displaying it, as well as 15 an RFC 2822 compliant date output for shell scripting 16 mail commands */ 17 18/* Input parsing code is always bulky - used heavy duty libc stuff as 19 much as possible, missed out a lot of bounds checking */ 20 21//config:config DATE 22//config: bool "date (7.1 kb)" 23//config: default y 24//config: help 25//config: date is used to set the system date or display the 26//config: current time in the given format. 27//config: 28//config:config FEATURE_DATE_ISOFMT 29//config: bool "Enable ISO date format output (-I)" 30//config: default y 31//config: depends on DATE 32//config: help 33//config: Enable option (-I) to output an ISO-8601 compliant 34//config: date/time string. 35//config: 36//config:# defaults to "no": stat's nanosecond field is a bit non-portable 37//config:config FEATURE_DATE_NANO 38//config: bool "Support %[num]N nanosecond format specifier" 39//config: default n # syscall(__NR_clock_gettime) 40//config: depends on DATE 41//config: select PLATFORM_LINUX 42//config: help 43//config: Support %[num]N format specifier. Adds ~250 bytes of code. 44//config: 45//config:config FEATURE_DATE_COMPAT 46//config: bool "Support weird 'date MMDDhhmm[[YY]YY][.ss]' format" 47//config: default y 48//config: depends on DATE 49//config: help 50//config: System time can be set by 'date -s DATE' and simply 'date DATE', 51//config: but formats of DATE string are different. 'date DATE' accepts 52//config: a rather weird MMDDhhmm[[YY]YY][.ss] format with completely 53//config: unnatural placement of year between minutes and seconds. 54//config: date -s (and other commands like touch -d) use more sensible 55//config: formats (for one, ISO format YYYY-MM-DD hh:mm:ss.ssssss). 56//config: 57//config: With this option off, 'date DATE' is 'date -s DATE' support 58//config: the same format. With it on, 'date DATE' additionally supports 59//config: MMDDhhmm[[YY]YY][.ss] format. 60 61//applet:IF_DATE(APPLET_NOEXEC(date, date, BB_DIR_BIN, BB_SUID_DROP, date)) 62/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */ 63 64//kbuild:lib-$(CONFIG_DATE) += date.o 65 66/* GNU coreutils 6.9 man page: 67 * date [OPTION]... [+FORMAT] 68 * date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]] 69 * -d, --date=STRING 70 * display time described by STRING, not 'now' 71 * -f, --file=DATEFILE 72 * like --date once for each line of DATEFILE 73 * -r, --reference=FILE 74 * display the last modification time of FILE 75 * -R, --rfc-2822 76 * output date and time in RFC 2822 format. 77 * Example: Mon, 07 Aug 2006 12:34:56 -0600 78 * --rfc-3339=TIMESPEC 79 * output date and time in RFC 3339 format. 80 * TIMESPEC='date', 'seconds', or 'ns' 81 * Date and time components are separated by a single space: 82 * 2006-08-07 12:34:56-06:00 83 * -s, --set=STRING 84 * set time described by STRING 85 * -u, --utc, --universal 86 * print or set Coordinated Universal Time 87 * 88 * Busybox: 89 * long options are not supported 90 * -f is not supported 91 * -I seems to roughly match --rfc-3339, but -I has _optional_ param 92 * (thus "-I seconds" doesn't work, only "-Iseconds"), 93 * and does not support -Ins 94 * -D FMT is a bbox extension for _input_ conversion of -d DATE 95 */ 96 97//usage:#define date_trivial_usage 98//usage: "[OPTIONS] [+FMT] [TIME]" 99//usage:#define date_full_usage "\n\n" 100//usage: "Display time (using +FMT), or set time\n" 101//usage: IF_NOT_LONG_OPTS( 102//usage: "\n [-s] TIME Set time to TIME" 103//usage: "\n -u Work in UTC (don't convert to local time)" 104//usage: "\n -R Output RFC-2822 compliant date string" 105//usage: ) IF_LONG_OPTS( 106//usage: "\n [-s,--set] TIME Set time to TIME" 107//usage: "\n -u,--utc Work in UTC (don't convert to local time)" 108//usage: "\n -R,--rfc-2822 Output RFC-2822 compliant date string" 109//usage: ) 110//usage: IF_FEATURE_DATE_ISOFMT( 111//usage: "\n -I[SPEC] Output ISO-8601 compliant date string" 112//usage: "\n SPEC='date' (default) for date only," 113//usage: "\n 'hours', 'minutes', or 'seconds' for date and" 114//usage: "\n time to the indicated precision" 115//usage: ) 116//usage: IF_NOT_LONG_OPTS( 117//usage: "\n -r FILE Display last modification time of FILE" 118//usage: "\n -d TIME Display TIME, not 'now'" 119//usage: ) IF_LONG_OPTS( 120//usage: "\n -r,--reference FILE Display last modification time of FILE" 121//usage: "\n -d,--date TIME Display TIME, not 'now'" 122//usage: ) 123//usage: IF_FEATURE_DATE_ISOFMT( 124//usage: "\n -D FMT Use FMT for -d TIME conversion" 125//usage: ) 126//usage: "\n" 127//usage: "\nRecognized TIME formats:" 128//usage: "\n hh:mm[:ss]" 129//usage: "\n [YYYY.]MM.DD-hh:mm[:ss]" 130//usage: "\n YYYY-MM-DD hh:mm[:ss]" 131//usage: "\n [[[[[YY]YY]MM]DD]hh]mm[.ss]" 132//usage: IF_FEATURE_DATE_COMPAT( 133//usage: "\n 'date TIME' form accepts MMDDhhmm[[YY]YY][.ss] instead" 134//usage: ) 135//usage: 136//usage:#define date_example_usage 137//usage: "$ date\n" 138//usage: "Wed Apr 12 18:52:41 MDT 2000\n" 139 140#include "libbb.h" 141#include "common_bufsiz.h" 142#if ENABLE_FEATURE_DATE_NANO 143# include <sys/syscall.h> 144#endif 145 146enum { 147 OPT_RFC2822 = (1 << 0), /* R */ 148 OPT_SET = (1 << 1), /* s */ 149 OPT_UTC = (1 << 2), /* u */ 150 OPT_DATE = (1 << 3), /* d */ 151 OPT_REFERENCE = (1 << 4), /* r */ 152 OPT_TIMESPEC = (1 << 5) * ENABLE_FEATURE_DATE_ISOFMT, /* I */ 153 OPT_HINT = (1 << 6) * ENABLE_FEATURE_DATE_ISOFMT, /* D */ 154}; 155 156#if ENABLE_LONG_OPTS 157static const char date_longopts[] ALIGN1 = 158 "rfc-822\0" No_argument "R" 159 "rfc-2822\0" No_argument "R" 160 "set\0" Required_argument "s" 161 "utc\0" No_argument "u" 162 /* "universal\0" No_argument "u" */ 163 "date\0" Required_argument "d" 164 "reference\0" Required_argument "r" 165 ; 166#endif 167 168/* We are a NOEXEC applet. 169 * Obstacles to NOFORK: 170 * - we change env 171 * - xasprintf result not freed 172 * - after xasprintf we use other xfuncs 173 */ 174 175static void maybe_set_utc(int opt) 176{ 177 if (opt & OPT_UTC) 178 putenv((char*)"TZ=UTC0"); 179} 180 181int date_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; 182int date_main(int argc UNUSED_PARAM, char **argv) 183{ 184 struct timespec ts; 185 struct tm tm_time; 186 char buf_fmt_dt2str[64]; 187 unsigned opt; 188 int ifmt = -1; 189 char *date_str; 190 char *fmt_dt2str; 191 char *fmt_str2dt; 192 char *filename; 193 char *isofmt_arg = NULL; 194 195 opt = getopt32long(argv, "^" 196 "Rs:ud:r:" 197 IF_FEATURE_DATE_ISOFMT("I::D:") 198 "\0" 199 "d--s:s--d" 200 IF_FEATURE_DATE_ISOFMT(":R--I:I--R"), 201 date_longopts, 202 &date_str, &date_str, &filename 203 IF_FEATURE_DATE_ISOFMT(, &isofmt_arg, &fmt_str2dt) 204 ); 205 argv += optind; 206 207 maybe_set_utc(opt); 208 209 if (ENABLE_FEATURE_DATE_ISOFMT && (opt & OPT_TIMESPEC)) { 210 ifmt = 0; /* default is date */ 211 if (isofmt_arg) { 212 static const char isoformats[] ALIGN1 = 213 "date\0""hours\0""minutes\0""seconds\0"; /* ns? */ 214 ifmt = index_in_substrings(isoformats, isofmt_arg); 215 if (ifmt < 0) 216 bb_show_usage(); 217 } 218 } 219 220 fmt_dt2str = NULL; 221 if (argv[0] && argv[0][0] == '+') { 222 fmt_dt2str = &argv[0][1]; /* skip over the '+' */ 223 argv++; 224 } 225 if (!(opt & (OPT_SET | OPT_DATE))) { 226 opt |= OPT_SET; 227 date_str = argv[0]; /* can be NULL */ 228 if (date_str) { 229#if ENABLE_FEATURE_DATE_COMPAT 230 int len = strspn(date_str, "0123456789"); 231 if (date_str[len] == '\0' 232 || (date_str[len] == '.' 233 && isdigit(date_str[len+1]) 234 && isdigit(date_str[len+2]) 235 && date_str[len+3] == '\0' 236 ) 237 ) { 238 /* Dreaded MMDDhhmm[[CC]YY][.ss] format! 239 * It does not match -d or -s format. 240 * Some users actually do use it. 241 */ 242 len -= 8; 243 if (len < 0 || len > 4 || (len & 1)) 244 bb_error_msg_and_die(bb_msg_invalid_date, date_str); 245 if (len != 0) { /* move YY or CCYY to front */ 246 char buf[4]; 247 memcpy(buf, date_str + 8, len); 248 memmove(date_str + len, date_str, 8); 249 memcpy(date_str, buf, len); 250 } 251 } 252#endif 253 argv++; 254 } 255 } 256 if (*argv) 257 bb_show_usage(); 258 259 /* Now we have parsed all the information except the date format 260 * which depends on whether the clock is being set or read */ 261 262 if (opt & OPT_REFERENCE) { 263 struct stat statbuf; 264 xstat(filename, &statbuf); 265 ts.tv_sec = statbuf.st_mtime; 266#if ENABLE_FEATURE_DATE_NANO 267 ts.tv_nsec = statbuf.st_mtim.tv_nsec; 268 /* Some toolchains use .st_mtimensec instead of st_mtim.tv_nsec. 269 * If you need #define _SVID_SOURCE 1 to enable st_mtim.tv_nsec, 270 * drop a mail to project mailing list please 271 */ 272#endif 273 } else { 274#if ENABLE_FEATURE_DATE_NANO 275 /* libc has incredibly messy way of doing this, 276 * typically requiring -lrt. We just skip all this mess */ 277 syscall(__NR_clock_gettime, CLOCK_REALTIME, &ts); 278#else 279 time(&ts.tv_sec); 280#endif 281 } 282 localtime_r(&ts.tv_sec, &tm_time); 283 284 /* If date string is given, update tm_time, and maybe set date */ 285 if (date_str != NULL) { 286 /* Zero out fields - take her back to midnight! */ 287 tm_time.tm_sec = 0; 288 tm_time.tm_min = 0; 289 tm_time.tm_hour = 0; 290 291 /* Process any date input to UNIX time since 1 Jan 1970 */ 292 if (ENABLE_FEATURE_DATE_ISOFMT && (opt & OPT_HINT)) { 293 if (strptime(date_str, fmt_str2dt, &tm_time) == NULL) 294 bb_error_msg_and_die(bb_msg_invalid_date, date_str); 295 } else { 296 parse_datestr(date_str, &tm_time); 297 } 298 299 /* Correct any day of week and day of year etc. fields */ 300 /* Be sure to recheck dst (but not if date is time_t format) */ 301 if (date_str[0] != '@') 302 tm_time.tm_isdst = -1; 303 ts.tv_sec = validate_tm_time(date_str, &tm_time); 304 305 /* if setting time, set it */ 306 if ((opt & OPT_SET) && stime(&ts.tv_sec) < 0) { 307 bb_perror_msg("can't set date"); 308 } 309 } 310 311 /* Display output */ 312 313 /* Deal with format string */ 314 if (fmt_dt2str == NULL) { 315 int i; 316 fmt_dt2str = buf_fmt_dt2str; 317 if (ENABLE_FEATURE_DATE_ISOFMT && ifmt >= 0) { 318 /* -I[SPEC]: 0:date 1:hours 2:minutes 3:seconds */ 319 strcpy(fmt_dt2str, "%Y-%m-%dT%H:%M:%S"); 320 i = 8 + 3 * ifmt; 321 if (ifmt != 0) { 322 /* TODO: if (ifmt==4) i += sprintf(&fmt_dt2str[i], ",%09u", nanoseconds); */ 323 format_utc: 324 fmt_dt2str[i++] = '%'; 325 fmt_dt2str[i++] = (opt & OPT_UTC) ? 'Z' : 'z'; 326 } 327 fmt_dt2str[i] = '\0'; 328 } else if (opt & OPT_RFC2822) { 329 /* -R. undo busybox.c setlocale */ 330 if (ENABLE_LOCALE_SUPPORT) 331 setlocale(LC_TIME, "C"); 332 strcpy(fmt_dt2str, "%a, %d %b %Y %H:%M:%S "); 333 i = sizeof("%a, %d %b %Y %H:%M:%S ")-1; 334 goto format_utc; 335 } else { /* default case */ 336 fmt_dt2str = (char*)"%a %b %e %H:%M:%S %Z %Y"; 337 } 338 } 339#if ENABLE_FEATURE_DATE_NANO 340 else { 341 /* User-specified fmt_dt2str */ 342 /* Search for and process "%N" */ 343 char *p = fmt_dt2str; 344 while ((p = strchr(p, '%')) != NULL) { 345 int n, m; 346 unsigned pres, scale; 347 348 p++; 349 if (*p == '%') { 350 p++; 351 continue; 352 } 353 n = strspn(p, "0123456789"); 354 if (p[n] != 'N') { 355 p += n; 356 continue; 357 } 358 /* We have "%[nnn]N" */ 359 p[-1] = '\0'; 360 p[n] = '\0'; 361 scale = 1; 362 pres = 9; 363 if (n) { 364 pres = xatoi_positive(p); 365 if (pres == 0) 366 pres = 9; 367 m = 9 - pres; 368 while (--m >= 0) 369 scale *= 10; 370 } 371 372 m = p - fmt_dt2str; 373 p += n + 1; 374 fmt_dt2str = xasprintf("%s%0*u%s", fmt_dt2str, pres, (unsigned)ts.tv_nsec / scale, p); 375 p = fmt_dt2str + m; 376 } 377 } 378#endif 379 380#define date_buf bb_common_bufsiz1 381 setup_common_bufsiz(); 382 if (*fmt_dt2str == '\0') { 383 /* With no format string, just print a blank line */ 384 date_buf[0] = '\0'; 385 } else { 386 /* Handle special conversions */ 387 if (is_prefixed_with(fmt_dt2str, "%f")) { 388 fmt_dt2str = (char*)"%Y.%m.%d-%H:%M:%S"; 389 } 390 /* Generate output string */ 391 strftime(date_buf, COMMON_BUFSIZE, fmt_dt2str, &tm_time); 392 } 393 puts(date_buf); 394 395 return EXIT_SUCCESS; 396} 397