coreutils/lib/posixtm.c
Jim Meyering 035abbb7c6 (posixtime) [lint]: Initialize *all* of tm0, not just
the .tm_year member, since otherwise gcc-4.0 would now warn about
tm_zone, tm_gmtoff, tm_isdst, tm_yday, tm_wday.
2005-07-03 21:10:31 +00:00

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/* Parse dates for touch and date.
Copyright (C) 1989, 1990, 1991, 1998, 2000, 2001, 2002, 2003, 2004, 2005
Free Software Foundation Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
/* Yacc-based version written by Jim Kingdon and David MacKenzie.
Rewritten by Jim Meyering. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <string.h>
#ifdef TM_IN_SYS_TIME
# include <sys/time.h>
#else
# include <time.h>
#endif
#include "posixtm.h"
#if USE_UNLOCKED_IO
# include "unlocked-io.h"
#endif
/* Use this to suppress gcc's `...may be used before initialized' warnings. */
#ifdef lint
# define IF_LINT(Code) Code
#else
# define IF_LINT(Code) /* empty */
#endif
/* ISDIGIT differs from isdigit, as follows:
- Its arg may be any int or unsigned int; it need not be an unsigned char.
- It's guaranteed to evaluate its argument exactly once.
- It's typically faster.
POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to
ISDIGIT_LOCALE unless it's important to use the locale's definition
of `digit' even when the host does not conform to POSIX. */
#define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9)
time_t mktime ();
/*
POSIX requires:
touch -t [[CC]YY]mmddhhmm[.ss] FILE...
8, 10, or 12 digits, followed by optional .ss
(PDS_LEADING_YEAR | PDS_CENTURY | PDS_SECONDS)
touch mmddhhmm[YY] FILE... (obsoleted by POSIX 1003.1-2001)
8 or 10 digits
(PDS_TRAILING_YEAR)
date mmddhhmm[[CC]YY]
8, 10, or 12 digits
(PDS_TRAILING_YEAR | PDS_CENTURY)
*/
static int
year (struct tm *tm, const int *digit_pair, size_t n, int allow_century)
{
switch (n)
{
case 1:
tm->tm_year = *digit_pair;
/* Deduce the century based on the year.
POSIX requires that 00-68 be interpreted as 2000-2068,
and that 69-99 be interpreted as 1969-1999. */
if (digit_pair[0] <= 68)
tm->tm_year += 100;
break;
case 2:
if (!allow_century)
return 1;
tm->tm_year = digit_pair[0] * 100 + digit_pair[1] - 1900;
break;
case 0:
{
time_t now;
struct tm *tmp;
/* Use current year. */
time (&now);
tmp = localtime (&now);
if (! tmp)
return 1;
tm->tm_year = tmp->tm_year;
}
break;
default:
abort ();
}
return 0;
}
static int
posix_time_parse (struct tm *tm, const char *s, unsigned int syntax_bits)
{
const char *dot = NULL;
int pair[6];
int *p;
size_t i;
size_t s_len = strlen (s);
size_t len = (((syntax_bits & PDS_SECONDS) && (dot = strchr (s, '.')))
? (size_t) (dot - s)
: s_len);
if (len != 8 && len != 10 && len != 12)
return 1;
if (dot)
{
if (!(syntax_bits & PDS_SECONDS))
return 1;
if (s_len - len != 3)
return 1;
}
for (i = 0; i < len; i++)
if (!ISDIGIT (s[i]))
return 1;
len /= 2;
for (i = 0; i < len; i++)
pair[i] = 10 * (s[2*i] - '0') + s[2*i + 1] - '0';
p = pair;
if (syntax_bits & PDS_LEADING_YEAR)
{
if (year (tm, p, len - 4, syntax_bits & PDS_CENTURY))
return 1;
p += len - 4;
len = 4;
}
/* Handle 8 digits worth of `MMDDhhmm'. */
tm->tm_mon = *p++ - 1;
tm->tm_mday = *p++;
tm->tm_hour = *p++;
tm->tm_min = *p++;
len -= 4;
/* Handle any trailing year. */
if (syntax_bits & PDS_TRAILING_YEAR)
{
if (year (tm, p, len, syntax_bits & PDS_CENTURY))
return 1;
}
/* Handle seconds. */
if (!dot)
{
tm->tm_sec = 0;
}
else
{
int seconds;
++dot;
if (!ISDIGIT (dot[0]) || !ISDIGIT (dot[1]))
return 1;
seconds = 10 * (dot[0] - '0') + dot[1] - '0';
tm->tm_sec = seconds;
}
return 0;
}
/* Parse a POSIX-style date, returning true if successful. */
bool
posixtime (time_t *p, const char *s, unsigned int syntax_bits)
{
struct tm tm0
#ifdef lint
/* Placate gcc-4's -Wuninitialized.
posix_time_parse fails to set all of tm0 only when it returns
nonzero (due to year() returning nonzero), and in that case,
this code doesn't use the tm0 at all. */
= { 0, }
#endif
;
struct tm tm1;
struct tm const *tm;
time_t t;
if (posix_time_parse (&tm0, s, syntax_bits))
return false;
tm1 = tm0;
tm1.tm_isdst = -1;
t = mktime (&tm1);
if (t != (time_t) -1)
tm = &tm1;
else
{
/* mktime returns -1 for errors, but -1 is also a valid time_t
value. Check whether an error really occurred. */
tm = localtime (&t);
if (! tm)
return false;
}
/* Reject dates like "September 31" and times like "25:61". */
if ((tm0.tm_year ^ tm->tm_year)
| (tm0.tm_mon ^ tm->tm_mon)
| (tm0.tm_mday ^ tm->tm_mday)
| (tm0.tm_hour ^ tm->tm_hour)
| (tm0.tm_min ^ tm->tm_min)
| (tm0.tm_sec ^ tm->tm_sec))
return false;
*p = t;
return true;
}
#ifdef TEST_POSIXTIME
/*
Test mainly with syntax_bits == 13
(aka: (PDS_LEADING_YEAR | PDS_CENTURY | PDS_SECONDS))
This test data assumes Universal Time, e.g., TZ="UTC0".
This test data also assumes that time_t is signed and is at least
39 bits wide, so that it can represent all years from 0000 through
9999. A host with 32-bit signed time_t can represent only time
stamps in the range 1901-12-13 20:45:52 through 2038-01-18
03:14:07 UTC, assuming POSIX time_t with no leap seconds, so test
cases outside this range will not work on such a host.
Also, the first two lines of test data assume that the current
year is 2002.
BEGIN-DATA
12131415.16 13 1039788916 Fri Dec 13 14:15:16 2002
12131415.16 13 1039788916 Fri Dec 13 14:15:16 2002
000001010000.00 13 -62167132800 Sun Jan 1 00:00:00 0000
190112132045.52 13 -2147483648 Fri Dec 13 20:45:52 1901
190112132045.53 13 -2147483647 Fri Dec 13 20:45:53 1901
190112132046.52 13 -2147483588 Fri Dec 13 20:46:52 1901
190112132145.52 13 -2147480048 Fri Dec 13 21:45:52 1901
190112142045.52 13 -2147397248 Sat Dec 14 20:45:52 1901
190201132045.52 13 -2144805248 Mon Jan 13 20:45:52 1902
196912312359.59 13 -1 Wed Dec 31 23:59:59 1969
197001010000.00 13 0 Thu Jan 1 00:00:00 1970
197001010000.01 13 1 Thu Jan 1 00:00:01 1970
197001010001.00 13 60 Thu Jan 1 00:01:00 1970
197001010100.00 13 3600 Thu Jan 1 01:00:00 1970
197001020000.00 13 86400 Fri Jan 2 00:00:00 1970
197002010000.00 13 2678400 Sun Feb 1 00:00:00 1970
197101010000.00 13 31536000 Fri Jan 1 00:00:00 1971
197001000000.00 13 * *
197000010000.00 13 * *
197001010000.60 13 * *
197001010060.00 13 * *
197001012400.00 13 * *
197001320000.00 13 * *
197013010000.00 13 * *
203801190314.06 13 2147483646 Tue Jan 19 03:14:06 2038
203801190314.07 13 2147483647 Tue Jan 19 03:14:07 2038
203801190314.08 13 2147483648 Tue Jan 19 03:14:08 2038
999912312359.59 13 253402300799 Fri Dec 31 23:59:59 9999
1112131415 13 1323785700 Tue Dec 13 14:15:00 2011
1112131415.16 13 1323785716 Tue Dec 13 14:15:16 2011
201112131415.16 13 1323785716 Tue Dec 13 14:15:16 2011
191112131415.16 13 -1831974284 Wed Dec 13 14:15:16 1911
203712131415.16 13 2144326516 Sun Dec 13 14:15:16 2037
3712131415.16 13 2144326516 Sun Dec 13 14:15:16 2037
6812131415.16 13 3122633716 Thu Dec 13 14:15:16 2068
6912131415.16 13 -1590284 Sat Dec 13 14:15:16 1969
7012131415.16 13 29945716 Sun Dec 13 14:15:16 1970
1213141599 2 945094500 Mon Dec 13 14:15:00 1999
1213141500 2 976716900 Wed Dec 13 14:15:00 2000
END-DATA
*/
# define MAX_BUFF_LEN 1024
int
main (void)
{
char buff[MAX_BUFF_LEN + 1];
buff[MAX_BUFF_LEN] = 0;
while (fgets (buff, MAX_BUFF_LEN, stdin) && buff[0])
{
char time_str[MAX_BUFF_LEN];
unsigned int syntax_bits;
time_t t;
if (sscanf (buff, "%s %u", time_str, &syntax_bits) != 2)
printf ("*\n");
else
{
printf ("%-15s %2u ", time_str, syntax_bits);
if (posixtime (&t, time_str, syntax_bits))
printf ("%12ld %s", (long int) t, ctime (&t));
else
printf ("%12s %s", "*", "*\n");
}
}
exit (0);
}
#endif
/*
Local Variables:
compile-command: "gcc -DTEST_POSIXTIME -DHAVE_CONFIG_H -I.. -g -O -Wall -W posixtm.c"
End:
*/