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/* 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"
/*
** 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 ** environ;
extern char * optarg;
extern int optind;
extern char * tzname[];
#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 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);
}
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