/* Copyright (C) 1991, 92, 93, 94, 95, 96 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library 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 Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <stddef.h> #include <stdlib.h> #include <string.h> #include <stdio.h> #include <sys/types.h> /* Some systems define `time_t' here. */ #include <sys/time.h> #include <time.h> #include <ctype.h> #include <limits.h> static unsigned int week (const struct tm *const, int, int); #define add(n, f) \ do \ { \ i += (n); \ if (i >= maxsize) \ return 0; \ else \ if (p) \ { \ f; \ p += (n); \ } \ } while (0) #define cpy(n, s) add((n), memcpy((void *) p, (void *) (s), (n))) #ifdef _LIBC #define fmt(n, args) add((n), if (sprintf args != (n)) return 0) #else #define fmt(n, args) add((n), sprintf args; if (strlen (p) != (n)) return 0) #endif /* Return the week in the year specified by TP, with weeks starting on STARTING_DAY. */ static unsigned int week(const struct tm *const tp , int starting_day , int max_preceding ) { int wday, dl, base; wday = tp->tm_wday - starting_day; if (wday < 0) wday += 7; /* Set DL to the day in the year of the first day of the week containing the day specified in TP. */ dl = tp->tm_yday - wday; /* For the computation following ISO 8601:1988 we set the number of the week containing January 1st to 1 if this week has more than MAX_PRECEDING days in the new year. For ISO 8601 this number is 3, for the other representation it is 7 (i.e., not to be fulfilled). */ base = ((dl + 7) % 7) > max_preceding ? 1 : 0; /* If DL is negative we compute the result as 0 unless we have to compute it according ISO 8601. In this case we have to return 53 or 1 if the week containing January 1st has less than 4 days in the new year or not. If DL is not negative we calculate the number of complete weeks for our week (DL / 7) plus 1 (because only for DL < 0 we are in week 0/53 and plus the number of the first week computed in the last step. */ return dl < 0 ? (dl < -max_preceding ? 53 : base) : base + 1 + dl / 7; } #ifndef _NL_CURRENT static char const weekday_name[][10] = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" }; static char const month_name[][10] = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" }; #endif /* Write information from TP into S according to the format string FORMAT, writing no more that MAXSIZE characters (including the terminating '\0') and returning number of characters written. If S is NULL, nothing will be written anywhere, so to determine how many characters would be written, use NULL for S and (size_t) UINT_MAX for MAXSIZE. */ size_t strftime( char *s , size_t maxsize , const char *format , register const struct tm *tp) { int hour12 = tp->tm_hour; #ifdef _NL_CURRENT const char *const a_wkday = _NL_CURRENT (LC_TIME, ABDAY_1 + tp->tm_wday); const char *const f_wkday = _NL_CURRENT (LC_TIME, DAY_1 + tp->tm_wday); const char *const a_month = _NL_CURRENT (LC_TIME, ABMON_1 + tp->tm_mon); const char *const f_month = _NL_CURRENT (LC_TIME, MON_1 + tp->tm_mon); const char *const ampm = _NL_CURRENT (LC_TIME, hour12 > 11 ? PM_STR : AM_STR); size_t aw_len = strlen(a_wkday); size_t am_len = strlen(a_month); size_t ap_len = strlen (ampm); #else const char *const f_wkday = weekday_name[tp->tm_wday]; const char *const f_month = month_name[tp->tm_mon]; const char *const a_wkday = f_wkday; const char *const a_month = f_month; const char *const ampm = "AMPM" + 2 * (hour12 > 11); size_t aw_len = 3; size_t am_len = 3; size_t ap_len = 2; #endif size_t wkday_len = strlen(f_wkday); size_t month_len = strlen(f_month); const unsigned int y_week0 = week (tp, 0, 7); const unsigned int y_week1 = week (tp, 1, 7); const unsigned int y_week2 = week (tp, 1, 3); const char *zone; size_t zonelen; register size_t i = 0; register char *p = s; register const char *f; char number_fmt[5]; /* Initialize the buffer we will use for the sprintf format for numbers. */ number_fmt[0] = '%'; zone = 0; #if HAVE_TM_ZONE zone = (const char *) tp->tm_zone; #endif if (!(zone && *zone) && tp->tm_isdst >= 0) zone = tzname[tp->tm_isdst]; if (!(zone && *zone)) zone = "???"; zonelen = strlen (zone); if (hour12 > 12) hour12 -= 12; else if (hour12 == 0) hour12 = 12; for (f = format; *f != '\0'; ++f) { enum { pad_zero, pad_space, pad_none } pad; /* Padding for number. */ unsigned int maxdigits; /* Max digits for numeric format. */ unsigned int number_value; /* Numeric value to be printed. */ const char *subfmt; #if HAVE_MBLEN if (!isascii(*f)) { /* Non-ASCII, may be a multibyte. */ int len = mblen(f, strlen(f)); if (len > 0) { cpy(len, f); continue; } } #endif if (*f != '%') { add(1, *p = *f); continue; } /* Check for flags that can modify a number format. */ ++f; switch (*f) { case '_': pad = pad_space; ++f; break; case '-': pad = pad_none; ++f; break; default: pad = pad_zero; break; } /* Now do the specified format. */ switch (*f) { case '\0': case '%': add(1, *p = *f); break; case 'a': cpy(aw_len, a_wkday); break; case 'A': cpy(wkday_len, f_wkday); break; case 'b': case 'h': /* GNU extension. */ cpy(am_len, a_month); break; case 'B': cpy(month_len, f_month); break; case 'c': #ifdef _NL_CURRENT subfmt = _NL_CURRENT (LC_TIME, D_T_FMT); #else subfmt = "%a %b %d %H:%M:%S %Z %Y"; #endif subformat: { size_t len = strftime (p, maxsize - i, subfmt, tp); if (len == 0 && *subfmt) return 0; add(len, ); } break; #define DO_NUMBER(digits, value) \ maxdigits = digits; number_value = value; goto do_number #define DO_NUMBER_NOPAD(digits, value) \ maxdigits = digits; number_value = value; goto do_number_nopad case 'C': DO_NUMBER (2, (1900 + tp->tm_year) / 100); case 'x': #ifdef _NL_CURRENT subfmt = _NL_CURRENT (LC_TIME, D_FMT); goto subformat; #endif /* Fall through. */ case 'D': /* GNU extension. */ subfmt = "%m/%d/%y"; goto subformat; case 'd': DO_NUMBER (2, tp->tm_mday); case 'e': /* GNU extension: %d, but blank-padded. */ #if 0 DO_NUMBER_NOPAD (2, tp->tm_mday); #else DO_NUMBER (2, tp->tm_mday); #endif /* All numeric formats set MAXDIGITS and NUMBER_VALUE and then jump to one of these two labels. */ do_number_nopad: /* Force `-' flag. */ pad = pad_none; do_number: { /* Format the number according to the PAD flag. */ register char *nf = &number_fmt[1]; int printed; switch (pad) { case pad_zero: *nf++ = '0'; case pad_space: *nf++ = '0' + maxdigits; case pad_none: *nf++ = 'u'; *nf = '\0'; } #ifdef _LIBC if (i + maxdigits >= maxsize) return 0; printed = sprintf (p, number_fmt, number_value); i += printed; p += printed; #else add (maxdigits, sprintf (p, number_fmt, number_value); printed = strlen (p)); #endif break; } case 'H': DO_NUMBER (2, tp->tm_hour); case 'I': DO_NUMBER (2, hour12); case 'k': /* GNU extension. */ DO_NUMBER_NOPAD (2, tp->tm_hour); case 'l': /* GNU extension. */ DO_NUMBER_NOPAD (2, hour12); case 'j': DO_NUMBER (3, 1 + tp->tm_yday); case 'M': DO_NUMBER (2, tp->tm_min); case 'm': DO_NUMBER (2, tp->tm_mon + 1); case 'n': /* GNU extension. */ add (1, *p = '\n'); break; case 'p': cpy(ap_len, ampm); break; case 'R': /* GNU extension. */ subfmt = "%H:%M"; goto subformat; case 'r': /* GNU extension. */ subfmt = "%I:%M:%S %p"; goto subformat; case 'S': DO_NUMBER (2, tp->tm_sec); case 'X': #ifdef _NL_CURRENT subfmt = _NL_CURRENT (LC_TIME, T_FMT); goto subformat; #endif /* Fall through. */ case 'T': /* GNU extenstion. */ subfmt = "%H:%M:%S"; goto subformat; case 't': /* GNU extenstion. */ add (1, *p = '\t'); break; case 'U': DO_NUMBER (2, y_week0); case 'V': DO_NUMBER (2, y_week2); case 'W': DO_NUMBER (2, y_week1); case 'w': DO_NUMBER (1, tp->tm_wday); case 'Y': DO_NUMBER (4, 1900 + tp->tm_year); case 'y': DO_NUMBER (2, tp->tm_year % 100); case 'Z': cpy(zonelen, zone); break; default: /* Bad format. */ break; } } if (p) *p = '\0'; return i; }