diff options
Diffstat (limited to 'date.c')
| -rw-r--r-- | date.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/date.c b/date.c new file mode 100644 index 000000000000..2cc533fdd4d2 --- /dev/null +++ b/date.c @@ -0,0 +1,237 @@ +/* Display or set the current time and date. */ + +/* Copyright 1985, 1987, 1988 The Regents of the University of California. + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + 3. Neither the name of the University nor the names of its contributors + may be used to endorse or promote products derived from this software + without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND + ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + SUCH DAMAGE. */ + +#include "private.h" +#include <locale.h> +#include <stdio.h> + +/* +** The two things date knows about time are. . . +*/ + +#ifndef TM_YEAR_BASE +#define TM_YEAR_BASE 1900 +#endif /* !defined TM_YEAR_BASE */ + +#ifndef SECSPERMIN +#define SECSPERMIN 60 +#endif /* !defined SECSPERMIN */ + +#if !HAVE_POSIX_DECLS +extern char * optarg; +extern int optind; +#endif + +static int retval = EXIT_SUCCESS; + +static void display(const char *, time_t); +static void dogmt(void); +static void errensure(void); +static void timeout(FILE *, const char *, const struct tm *); +static _Noreturn void usage(void); + +int +main(const int argc, char *argv[]) +{ + register const char * format; + register const char * cp; + register int ch; + register bool rflag = false; + time_t t; + intmax_t secs; + char * endarg; + +#ifdef LC_ALL + setlocale(LC_ALL, ""); +#endif /* defined(LC_ALL) */ +#if HAVE_GETTEXT +#ifdef TZ_DOMAINDIR + bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR); +#endif /* defined(TEXTDOMAINDIR) */ + textdomain(TZ_DOMAIN); +#endif /* HAVE_GETTEXT */ + t = time(NULL); + format = NULL; + while ((ch = getopt(argc, argv, "ucr:")) != EOF && ch != -1) { + switch (ch) { + default: + usage(); + case 'u': /* do it in UT */ + case 'c': + dogmt(); + break; + case 'r': /* seconds since 1970 */ + if (rflag) { + fprintf(stderr, + _("date: error: multiple -r's used")); + usage(); + } + rflag = true; + errno = 0; + secs = strtoimax (optarg, &endarg, 0); + if (*endarg || optarg == endarg) + errno = EINVAL; + else if (! (TIME_T_MIN <= secs && secs <= TIME_T_MAX)) + errno = ERANGE; + if (errno) { + perror(optarg); + errensure(); + exit(retval); + } + t = secs; + break; + } + } + while (optind < argc) { + cp = argv[optind++]; + if (*cp == '+') + if (format == NULL) + format = cp + 1; + else { + fprintf(stderr, +_("date: error: multiple formats in command line\n")); + usage(); + } + else { + fprintf(stderr, _("date: unknown operand: %s\n"), cp); + usage(); + } + } + + display(format, t); + return retval; +} + +static void +dogmt(void) +{ + static char ** fakeenv; + + if (fakeenv == NULL) { + register int from; + register int to; + register int n; + static char tzegmt0[] = "TZ=GMT0"; + + for (n = 0; environ[n] != NULL; ++n) + continue; + fakeenv = malloc((n + 2) * sizeof *fakeenv); + if (fakeenv == NULL) { + perror(_("Memory exhausted")); + errensure(); + exit(retval); + } + to = 0; + fakeenv[to++] = tzegmt0; + for (from = 1; environ[from] != NULL; ++from) + if (strncmp(environ[from], "TZ=", 3) != 0) + fakeenv[to++] = environ[from]; + fakeenv[to] = NULL; + environ = fakeenv; + } +} + +static void +errensure(void) +{ + if (retval == EXIT_SUCCESS) + retval = EXIT_FAILURE; +} + +static void +usage(void) +{ + fprintf(stderr, + _("date: usage: date [-u] [-c] [-r seconds]" + " [+format]\n")); + errensure(); + exit(retval); +} + +static void +display(char const *format, time_t now) +{ + struct tm *tmp; + + tmp = localtime(&now); + if (!tmp) { + fprintf(stderr, + _("date: error: time out of range\n")); + errensure(); + return; + } + timeout(stdout, format ? format : "%+", tmp); + putchar('\n'); + fflush(stdout); + fflush(stderr); + if (ferror(stdout) || ferror(stderr)) { + fprintf(stderr, + _("date: error: couldn't write results\n")); + errensure(); + } +} + +#define INCR 1024 + +static void +timeout(FILE *fp, char const *format, struct tm const *tmp) +{ + char * cp; + size_t result; + size_t size; + struct tm tm; + + if (*format == '\0') + return; + if (!tmp) { + fprintf(stderr, _("date: error: time out of range\n")); + errensure(); + return; + } + tm = *tmp; + tmp = &tm; + size = INCR; + cp = malloc(size); + for ( ; ; ) { + if (cp == NULL) { + fprintf(stderr, + _("date: error: can't get memory\n")); + errensure(); + exit(retval); + } + cp[0] = '\1'; + result = strftime(cp, size, format, tmp); + if (result != 0 || cp[0] == '\0') + break; + size += INCR; + cp = realloc(cp, size); + } + fwrite(cp, 1, result, fp); + free(cp); +} |