git.maemo.org Git - busybox4maemo/blob - coreutils/date.c

   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 Fischer
   9  *
  10  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  11 */
  12
  13 #include "libbb.h"
  14
  15 /* This 'date' command supports only 2 time setting formats,
  16    all the GNU strftime stuff (its in libc, lets use it),
  17    setting time using UTC and displaying it, as well as
  18    an RFC 2822 compliant date output for shell scripting
  19    mail commands */
  20
  21 /* Input parsing code is always bulky - used heavy duty libc stuff as
  22    much as possible, missed out a lot of bounds checking */
  23
  24 /* Default input handling to save surprising some people */
  25
  26
  27 #define DATE_OPT_RFC2822        0x01
  28 #define DATE_OPT_SET            0x02
  29 #define DATE_OPT_UTC            0x04
  30 #define DATE_OPT_DATE           0x08
  31 #define DATE_OPT_REFERENCE      0x10
  32 #define DATE_OPT_TIMESPEC       0x20
  33 #define DATE_OPT_HINT           0x40
  34
  35 static void maybe_set_utc(int opt)
  36 {
  37         if (opt & DATE_OPT_UTC)
  38                 putenv((char*)"TZ=UTC0");
  39 }
  40
  41 int date_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  42 int date_main(int argc, char **argv)
  43 {
  44         time_t tm;
  45         struct tm tm_time;
  46         unsigned opt;
  47         int ifmt = -1;
  48         char *date_str = NULL;
  49         char *date_fmt = NULL;
  50         char *filename = NULL;
  51         char *isofmt_arg;
  52         char *hintfmt_arg;
  53
  54         opt_complementary = "d--s:s--d"
  55                 USE_FEATURE_DATE_ISOFMT(":R--I:I--R");
  56         opt = getopt32(argv, "Rs:ud:r:"
  57                         USE_FEATURE_DATE_ISOFMT("I::D:"),
  58                         &date_str, &date_str, &filename
  59                         USE_FEATURE_DATE_ISOFMT(, &isofmt_arg, &hintfmt_arg));
  60         maybe_set_utc(opt);
  61
  62         if (ENABLE_FEATURE_DATE_ISOFMT && (opt & DATE_OPT_TIMESPEC)) {
  63                 if (!isofmt_arg) {
  64                         ifmt = 0; /* default is date */
  65                 } else {
  66                         static const char *const isoformats[] = {
  67                                 "date", "hours", "minutes", "seconds"
  68                         };
  69
  70                         for (ifmt = 0; ifmt < 4; ifmt++)
  71                                 if (!strcmp(isofmt_arg, isoformats[ifmt]))
  72                                         goto found;
  73                         /* parse error */
  74                         bb_show_usage();
  75  found: ;
  76                 }
  77         }
  78
  79         /* XXX, date_fmt == NULL from this always */
  80         if ((date_fmt == NULL) && (optind < argc) && (argv[optind][0] == '+')) {
  81                 date_fmt = &argv[optind][1];    /* Skip over the '+' */
  82         } else if (date_str == NULL) {
  83                 opt |= DATE_OPT_SET;
  84                 date_str = argv[optind];
  85         }
  86
  87         /* Now we have parsed all the information except the date format
  88            which depends on whether the clock is being set or read */
  89
  90         if (filename) {
  91                 struct stat statbuf;
  92                 xstat(filename, &statbuf);
  93                 tm = statbuf.st_mtime;
  94         } else
  95                 time(&tm);
  96         memcpy(&tm_time, localtime(&tm), sizeof(tm_time));
  97         /* Zero out fields - take her back to midnight! */
  98         if (date_str != NULL) {
  99                 tm_time.tm_sec = 0;
 100                 tm_time.tm_min = 0;
 101                 tm_time.tm_hour = 0;
 102
 103                 /* Process any date input to UNIX time since 1 Jan 1970 */
 104                 if (ENABLE_FEATURE_DATE_ISOFMT && (opt & DATE_OPT_HINT)) {
 105                         strptime(date_str, hintfmt_arg, &tm_time);
 106                 } else if (strchr(date_str, ':') != NULL) {
 107                         /* Parse input and assign appropriately to tm_time */
 108
 109                         if (sscanf(date_str, "%d:%d:%d", &tm_time.tm_hour, &tm_time.tm_min,
 110                                                                  &tm_time.tm_sec) == 3) {
 111                                 /* no adjustments needed */
 112                         } else if (sscanf(date_str, "%d:%d", &tm_time.tm_hour,
 113                                                                                 &tm_time.tm_min) == 2) {
 114                                 /* no adjustments needed */
 115                         } else if (sscanf(date_str, "%d.%d-%d:%d:%d", &tm_time.tm_mon,
 116                                                                 &tm_time.tm_mday, &tm_time.tm_hour,
 117                                                                 &tm_time.tm_min, &tm_time.tm_sec) == 5) {
 118                                 /* Adjust dates from 1-12 to 0-11 */
 119                                 tm_time.tm_mon -= 1;
 120                         } else if (sscanf(date_str, "%d.%d-%d:%d", &tm_time.tm_mon,
 121                                                                 &tm_time.tm_mday,
 122                                                                 &tm_time.tm_hour, &tm_time.tm_min) == 4) {
 123                                 /* Adjust dates from 1-12 to 0-11 */
 124                                 tm_time.tm_mon -= 1;
 125                         } else if (sscanf(date_str, "%d.%d.%d-%d:%d:%d", &tm_time.tm_year,
 126                                                                 &tm_time.tm_mon, &tm_time.tm_mday,
 127                                                                 &tm_time.tm_hour, &tm_time.tm_min,
 128                                                                         &tm_time.tm_sec) == 6) {
 129                                 tm_time.tm_year -= 1900;        /* Adjust years */
 130                                 tm_time.tm_mon -= 1;    /* Adjust dates from 1-12 to 0-11 */
 131                         } else if (sscanf(date_str, "%d.%d.%d-%d:%d", &tm_time.tm_year,
 132                                                                 &tm_time.tm_mon, &tm_time.tm_mday,
 133                                                                 &tm_time.tm_hour, &tm_time.tm_min) == 5) {
 134                                 tm_time.tm_year -= 1900;        /* Adjust years */
 135                                 tm_time.tm_mon -= 1;    /* Adjust dates from 1-12 to 0-11 */
 136                         } else {
 137                                 bb_error_msg_and_die(bb_msg_invalid_date, date_str);
 138                         }
 139                 } else {
 140                         int nr;
 141                         char *cp;
 142
 143                         nr = sscanf(date_str, "%2d%2d%2d%2d%d", &tm_time.tm_mon,
 144                                                 &tm_time.tm_mday, &tm_time.tm_hour, &tm_time.tm_min,
 145                                                 &tm_time.tm_year);
 146
 147                         if (nr < 4 || nr > 5) {
 148                                 bb_error_msg_and_die(bb_msg_invalid_date, date_str);
 149                         }
 150
 151                         cp = strchr(date_str, '.');
 152                         if (cp) {
 153                                 nr = sscanf(cp + 1, "%2d", &tm_time.tm_sec);
 154                                 if (nr != 1) {
 155                                         bb_error_msg_and_die(bb_msg_invalid_date, date_str);
 156                                 }
 157                         }
 158
 159                         /* correct for century  - minor Y2K problem here? */
 160                         if (tm_time.tm_year >= 1900) {
 161                                 tm_time.tm_year -= 1900;
 162                         }
 163                         /* adjust date */
 164                         tm_time.tm_mon -= 1;
 165                 }
 166
 167                 /* Correct any day of week and day of year etc. fields */
 168                 tm_time.tm_isdst = -1;  /* Be sure to recheck dst. */
 169                 tm = mktime(&tm_time);
 170                 if (tm < 0) {
 171                         bb_error_msg_and_die(bb_msg_invalid_date, date_str);
 172                 }
 173                 maybe_set_utc(opt);
 174
 175                 /* if setting time, set it */
 176                 if ((opt & DATE_OPT_SET) && stime(&tm) < 0) {
 177                         bb_perror_msg("cannot set date");
 178                 }
 179         }
 180
 181         /* Display output */
 182
 183         /* Deal with format string */
 184
 185         if (date_fmt == NULL) {
 186                 int i;
 187                 date_fmt = xzalloc(32);
 188                 if (ENABLE_FEATURE_DATE_ISOFMT && ifmt >= 0) {
 189                         strcpy(date_fmt, "%Y-%m-%d");
 190                         if (ifmt > 0) {
 191                                 i = 8;
 192                                 date_fmt[i++] = 'T';
 193                                 date_fmt[i++] = '%';
 194                                 date_fmt[i++] = 'H';
 195                                 if (ifmt > 1) {
 196                                         date_fmt[i++] = ':';
 197                                         date_fmt[i++] = '%';
 198                                         date_fmt[i++] = 'M';
 199                                 }
 200                                 if (ifmt > 2) {
 201                                         date_fmt[i++] = ':';
 202                                         date_fmt[i++] = '%';
 203                                         date_fmt[i++] = 'S';
 204                                 }
 205  format_utc:
 206                                 date_fmt[i++] = '%';
 207                                 date_fmt[i] = (opt & DATE_OPT_UTC) ? 'Z' : 'z';
 208                         }
 209                 } else if (opt & DATE_OPT_RFC2822) {
 210                         /* Undo busybox.c for date -R */
 211                         if (ENABLE_LOCALE_SUPPORT)
 212                                 setlocale(LC_TIME, "C");
 213                         strcpy(date_fmt, "%a, %d %b %Y %H:%M:%S ");
 214                         i = 22;
 215                         goto format_utc;
 216                 } else /* default case */
 217                         date_fmt = (char*)"%a %b %e %H:%M:%S %Z %Y";
 218         }
 219
 220 #define date_buf bb_common_bufsiz1
 221         if (*date_fmt == '\0') {
 222                 /* With no format string, just print a blank line */
 223                 date_buf[0] = '\0';
 224         } else {
 225                 /* Handle special conversions */
 226
 227                 if (strncmp(date_fmt, "%f", 2) == 0) {
 228                         date_fmt = (char*)"%Y.%m.%d-%H:%M:%S";
 229                 }
 230
 231                 /* Generate output string */
 232                 strftime(date_buf, sizeof(date_buf), date_fmt, &tm_time);
 233         }
 234         puts(date_buf);
 235
 236         return EXIT_SUCCESS;
 237 }