Edit
kc3-lang/gnulib/lib/posixtm.c
Jim Meyering
- lib/posixtm.c
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/* Parse dates for touch and date. Copyright (C) 1989, 1990, 1991, 1998, 2000 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Yacc-based version written by Jim Kingdon and David MacKenzie. Rewritten by Jim Meyering. */ #ifdef HAVE_CONFIG_H # include <config.h> #endif #include <stdio.h> #if HAVE_STDLIB_H # include <stdlib.h> #endif #include <sys/types.h> #if HAVE_STRING_H # include <string.h> #else # include <strings.h> #endif #ifdef TM_IN_SYS_TIME # include <sys/time.h> #else # include <time.h> #endif #include "posixtm.h" /* 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 1003.2-1992 section 2.5.2.1 page 50 lines 1556-1558 says that only '0' through '9' are digits. Prefer ISDIGIT to isdigit 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) (c) - '0' <= 9) /* The return value. */ static struct tm t; 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... (obsolescent) 8 or 10 digits (PDS_TRAILING_YEAR) date mmddhhmm[[CC]YY] 8, 10, or 12 digits (PDS_TRAILING_YEAR | PDS_CENTURY) */ static int year (const int *digit_pair, size_t n, int allow_century) { switch (n) { case 1: t.tm_year = *digit_pair; /* Deduce the century based on the year. See POSIX.2 section 4.63.3. */ if (digit_pair[0] <= 68) t.tm_year += 100; break; case 2: if (!allow_century) return 1; t.tm_year = digit_pair[0] * 100 + digit_pair[1]; if (t.tm_year < 1900) return 1; t.tm_year -= 1900; break; case 0: { time_t now; struct tm *tmp; /* Use current year. */ time (&now); tmp = localtime (&now); t.tm_year = tmp->tm_year; } break; default: abort (); } return 0; } static int posix_time_parse (const char *s, unsigned int syntax_bits) { const char *dot = NULL; int pair[6]; int *p; unsigned int i; size_t s_len = strlen (s); size_t len = (((syntax_bits & PDS_SECONDS) && (dot = strchr (s, '.'))) ? 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 (p, len - 4, syntax_bits & PDS_CENTURY)) return 1; p += len - 4; len = 4; } /* Handle 8 digits worth of `MMDDhhmm'. */ if (*p < 1 || *p > 12) return 1; t.tm_mon = *p - 1; ++p; --len; if (*p < 1 || *p > 31) return 1; t.tm_mday = *p; ++p; --len; if (*p < 0 || *p > 23) return 1; t.tm_hour = *p; ++p; --len; if (*p < 0 || *p > 59) return 1; t.tm_min = *p; ++p; --len; /* Handle any trailing year. */ if (syntax_bits & PDS_TRAILING_YEAR) { if (year (p, len, syntax_bits & PDS_CENTURY)) return 1; } /* Handle seconds. */ if (!dot) { t.tm_sec = 0; } else { int seconds; ++dot; if (!ISDIGIT (dot[0]) || !ISDIGIT (dot[1])) return 1; seconds = 10 * (dot[0] - '0') + dot[1] - '0'; if (seconds < 0 || seconds > 61) return 1; t.tm_sec = seconds; } return 0; } /* Parse a POSIX-style date and return it, or (time_t)-1 for an error. */ time_t posixtime (const char *s, unsigned int syntax_bits) { t.tm_isdst = -1; if (posix_time_parse (s, syntax_bits)) return (time_t)-1; else return mktime (&t); } /* Parse a POSIX-style date and return it, or NULL for an error. */ struct tm * posixtm (const char *s, unsigned int syntax_bits) { if (posixtime (s, syntax_bits) == -1) return NULL; return &t; } #ifdef TEST_POSIXTIME /* Test mainly with syntax_bits == 13 (aka: (PDS_LEADING_YEAR | PDS_CENTURY | PDS_SECONDS)) BEGIN-DATA 1112131415 13 1323807300 Tue Dec 13 14:15:00 2011 1112131415.16 13 1323807316 Tue Dec 13 14:15:16 2011 201112131415.16 13 1323807316 Tue Dec 13 14:15:16 2011 191112131415.16 13 -1 *** 203712131415.16 13 2144348116 Sun Dec 13 14:15:16 2037 3712131415.16 13 2144348116 Sun Dec 13 14:15:16 2037 6812131415.16 13 -1 *** 6912131415.16 13 -1 *** 7012131415.16 13 29967316 Sun Dec 13 14:15:16 1970 12131415.16 13 913580116 Sun Dec 13 14:15:16 1998 1213141599 2 945116100 Mon Dec 13 14:15:00 1999 1213141500 2 976738500 Wed Dec 13 14:15:00 2000 END-DATA */ # define MAX_BUFF_LEN 1024 int main () { 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; char *result; sscanf (buff, "%s %u", time_str, &syntax_bits); t = posixtime (time_str, syntax_bits); result = (t == (time_t) -1 ? "***" : ctime (&t)); printf ("%d %s\n", (int) t, result); } exit (0); } #endif