freebsd-dev/contrib/tzcode/date.c
Dag-Erling Smørgrav 75411d1572 Update tzcode to 2023c.
MFC after:      3 weeks
Sponsored by:   Klara, Inc.
Reviewed by:    philip
Differential Revision:  https://reviews.freebsd.org/D39712
2023-04-26 11:46:21 +02:00

218 lines
5.4 KiB
C

/* 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>
#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 *);
ATTRIBUTE_NORETURN static void usage(void);
int
main(const int argc, char *argv[])
{
register const char * format = "+%+";
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);
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) {
char const *e = strerror(errno);
fprintf(stderr, _("date: %s: %s\n"),
optarg, e);
errensure();
exit(retval);
}
t = secs;
break;
}
}
if (optind < argc) {
if (argc - optind != 1) {
fprintf(stderr,
_("date: error: multiple operands in command line\n"));
usage();
}
format = argv[optind];
if (*format != '+') {
fprintf(stderr, _("date: unknown operand: %s\n"), format);
usage();
}
}
display(format, t);
return retval;
}
static void
dogmt(void)
{
static char ** fakeenv;
if (fakeenv == NULL) {
static char tzeutc0[] = "TZ=UTC0";
ptrdiff_t from, to, n;
for (n = 0; environ[n] != NULL; ++n)
continue;
#if defined ckd_add && defined ckd_mul
if (!ckd_add(&n, n, 2) && !ckd_mul(&n, n, sizeof *fakeenv)
&& n <= INDEX_MAX)
fakeenv = malloc(n);
#else
if (n <= INDEX_MAX / sizeof *fakeenv - 2)
fakeenv = malloc((n + 2) * sizeof *fakeenv);
#endif
if (fakeenv == NULL) {
fprintf(stderr, _("date: Memory exhausted\n"));
errensure();
exit(retval);
}
to = 0;
fakeenv[to++] = tzeutc0;
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, tmp);
putchar('\n');
fflush(stdout);
fflush(stderr);
if (ferror(stdout) || ferror(stderr)) {
fprintf(stderr,
_("date: error: couldn't write results\n"));
errensure();
}
}
static void
timeout(FILE *fp, char const *format, struct tm const *tmp)
{
char *cp = NULL;
ptrdiff_t result;
ptrdiff_t size = 1024 / 2;
for ( ; ; ) {
#ifdef ckd_mul
bool bigger = !ckd_mul(&size, size, 2) && size <= INDEX_MAX;
#else
bool bigger = size <= INDEX_MAX / 2 && (size *= 2, true);
#endif
char *newcp = bigger ? realloc(cp, size) : NULL;
if (!newcp) {
fprintf(stderr,
_("date: error: can't get memory\n"));
errensure();
exit(retval);
}
cp = newcp;
result = strftime(cp, size, format, tmp);
if (result != 0)
break;
}
fwrite(cp + 1, 1, result - 1, fp);
free(cp);
}