/* $NetBSD: strptime.c,v 1.63.6.2 2024/04/16 18:33:47 martin Exp $ */ /*- * Copyright (c) 1997, 1998, 2005, 2008 The NetBSD Foundation, Inc. * All rights reserved. * * This code was contributed to The NetBSD Foundation by Klaus Klein. * Heavily optimised by David Laight * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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 #if defined(LIBC_SCCS) && !defined(lint) __RCSID("$NetBSD: strptime.c,v 1.63.6.2 2024/04/16 18:33:47 martin Exp $"); #endif #include "namespace.h" #include #include #include #include #include #include #include #include "private.h" #include "setlocale_local.h" #ifdef __weak_alias __weak_alias(strptime,_strptime) __weak_alias(strptime_l, _strptime_l) #endif static const u_char *conv_num(const unsigned char *, int *, uint, uint); static const u_char *find_string(const u_char *, int *, const char * const *, const char * const *, int); #define _TIME_LOCALE(loc) \ ((_TimeLocale *)((loc)->part_impl[(size_t)LC_TIME])) /* * We do not implement alternate representations. However, we always * check whether a given modifier is allowed for a certain conversion. */ #define ALT_E 0x01 #define ALT_O 0x02 #define LEGAL_ALT(x) { if (alt_format & ~(x)) return NULL; } #define S_YEAR (1 << 0) #define S_MON (1 << 1) #define S_YDAY (1 << 2) #define S_MDAY (1 << 3) #define S_WDAY (1 << 4) #define S_HOUR (1 << 5) #define HAVE_MDAY(s) (s & S_MDAY) #define HAVE_MON(s) (s & S_MON) #define HAVE_WDAY(s) (s & S_WDAY) #define HAVE_YDAY(s) (s & S_YDAY) #define HAVE_YEAR(s) (s & S_YEAR) #define HAVE_HOUR(s) (s & S_HOUR) static char utc[] = { "UTC" }; /* RFC-822/RFC-2822 */ static const char * const nast[5] = { "EST", "CST", "MST", "PST", "\0\0\0" }; static const char * const nadt[5] = { "EDT", "CDT", "MDT", "PDT", "\0\0\0" }; /* * Table to determine the ordinal date for the start of a month. * Ref: http://en.wikipedia.org/wiki/ISO_week_date */ static const int start_of_month[2][13] = { /* non-leap year */ { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }, /* leap year */ { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 } }; /* * Calculate the week day of the first day of a year. Valid for * the Gregorian calendar, which began Sept 14, 1752 in the UK * and its colonies. Ref: * http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week */ static int first_wday_of(int yr) { return ((2 * (3 - (yr / 100) % 4)) + (yr % 100) + ((yr % 100) / 4) + (isleap(yr) ? 6 : 0) + 1) % 7; } #define delim(p) ((p) == '\0' || isspace((unsigned char)(p))) static int fromzone(const unsigned char **bp, struct tm *tm, int mandatory) { timezone_t tz; char buf[512], *p; const unsigned char *rp; for (p = buf, rp = *bp; !delim(*rp) && p < &buf[sizeof(buf) - 1]; rp++) *p++ = *rp; *p = '\0'; if (mandatory) *bp = rp; if (!isalnum((unsigned char)*buf)) return 0; tz = tzalloc(buf); if (tz == NULL) return 0; *bp = rp; tm->tm_isdst = 0; /* XXX */ #ifdef TM_GMTOFF tm->TM_GMTOFF = tzgetgmtoff(tz, tm->tm_isdst); #endif #ifdef TM_ZONE // Can't use tzgetname() here because we are going to free() tm->TM_ZONE = NULL; /* XXX */ #endif tzfree(tz); return 1; } char * strptime(const char *buf, const char *fmt, struct tm *tm) { return strptime_l(buf, fmt, tm, _current_locale()); } char * strptime_l(const char *buf, const char *fmt, struct tm *tm, locale_t loc) { unsigned char c; const unsigned char *bp, *ep, *zname; int alt_format, i, split_year = 0, neg = 0, state = 0, day_offset = -1, week_offset = 0, offs, mandatory; const char *new_fmt; bp = (const u_char *)buf; while (bp != NULL && (c = *fmt++) != '\0') { /* Clear `alternate' modifier prior to new conversion. */ alt_format = 0; i = 0; /* Eat up white-space. */ if (isspace(c)) { while (isspace(*bp)) bp++; continue; } if (c != '%') goto literal; again: switch (c = *fmt++) { case '%': /* "%%" is converted to "%". */ literal: if (c != *bp++) return NULL; LEGAL_ALT(0); continue; /* * "Alternative" modifiers. Just set the appropriate flag * and start over again. */ case 'E': /* "%E?" alternative conversion modifier. */ LEGAL_ALT(0); alt_format |= ALT_E; goto again; case 'O': /* "%O?" alternative conversion modifier. */ LEGAL_ALT(0); alt_format |= ALT_O; goto again; /* * "Complex" conversion rules, implemented through recursion. */ case 'c': /* Date and time, using the locale's format. */ new_fmt = _TIME_LOCALE(loc)->d_t_fmt; state |= S_WDAY | S_MON | S_MDAY | S_YEAR; goto recurse; case 'D': /* The date as "%m/%d/%y". */ new_fmt = "%m/%d/%y"; LEGAL_ALT(0); state |= S_MON | S_MDAY | S_YEAR; goto recurse; case 'F': /* The date as "%Y-%m-%d". */ new_fmt = "%Y-%m-%d"; LEGAL_ALT(0); state |= S_MON | S_MDAY | S_YEAR; goto recurse; case 'R': /* The time as "%H:%M". */ new_fmt = "%H:%M"; LEGAL_ALT(0); goto recurse; case 'r': /* The time in 12-hour clock representation. */ new_fmt = _TIME_LOCALE(loc)->t_fmt_ampm; LEGAL_ALT(0); goto recurse; case 'T': /* The time as "%H:%M:%S". */ new_fmt = "%H:%M:%S"; LEGAL_ALT(0); goto recurse; case 'X': /* The time, using the locale's format. */ new_fmt = _TIME_LOCALE(loc)->t_fmt; goto recurse; case 'x': /* The date, using the locale's format. */ new_fmt = _TIME_LOCALE(loc)->d_fmt; state |= S_MON | S_MDAY | S_YEAR; recurse: bp = (const u_char *)strptime((const char *)bp, new_fmt, tm); LEGAL_ALT(ALT_E); continue; /* * "Elementary" conversion rules. */ case 'A': /* The day of week, using the locale's form. */ case 'a': bp = find_string(bp, &tm->tm_wday, _TIME_LOCALE(loc)->day, _TIME_LOCALE(loc)->abday, 7); LEGAL_ALT(0); state |= S_WDAY; continue; case 'B': /* The month, using the locale's form. */ case 'b': case 'h': bp = find_string(bp, &tm->tm_mon, _TIME_LOCALE(loc)->mon, _TIME_LOCALE(loc)->abmon, 12); LEGAL_ALT(0); state |= S_MON; continue; case 'C': /* The century number. */ i = 20; bp = conv_num(bp, &i, 0, 99); i = i * 100 - TM_YEAR_BASE; if (split_year) i += tm->tm_year % 100; split_year = 1; tm->tm_year = i; LEGAL_ALT(ALT_E); state |= S_YEAR; continue; case 'd': /* The day of month. */ case 'e': bp = conv_num(bp, &tm->tm_mday, 1, 31); LEGAL_ALT(ALT_O); state |= S_MDAY; continue; case 'k': /* The hour (24-hour clock representation). */ LEGAL_ALT(0); /* FALLTHROUGH */ case 'H': bp = conv_num(bp, &tm->tm_hour, 0, 23); LEGAL_ALT(ALT_O); state |= S_HOUR; continue; case 'l': /* The hour (12-hour clock representation). */ LEGAL_ALT(0); /* FALLTHROUGH */ case 'I': bp = conv_num(bp, &tm->tm_hour, 1, 12); if (tm->tm_hour == 12) tm->tm_hour = 0; LEGAL_ALT(ALT_O); state |= S_HOUR; continue; case 'j': /* The day of year. */ i = 1; bp = conv_num(bp, &i, 1, 366); tm->tm_yday = i - 1; LEGAL_ALT(0); state |= S_YDAY; continue; case 'M': /* The minute. */ bp = conv_num(bp, &tm->tm_min, 0, 59); LEGAL_ALT(ALT_O); continue; case 'm': /* The month. */ i = 1; bp = conv_num(bp, &i, 1, 12); tm->tm_mon = i - 1; LEGAL_ALT(ALT_O); state |= S_MON; continue; case 'p': /* The locale's equivalent of AM/PM. */ bp = find_string(bp, &i, _TIME_LOCALE(loc)->am_pm, NULL, 2); if (HAVE_HOUR(state) && tm->tm_hour > 11) return NULL; tm->tm_hour += i * 12; LEGAL_ALT(0); continue; case 'S': /* The seconds. */ bp = conv_num(bp, &tm->tm_sec, 0, 61); LEGAL_ALT(ALT_O); continue; case 's': { /* seconds since the epoch */ const time_t TIME_MAX = __type_max(time_t); time_t sse, d; if (*bp < '0' || *bp > '9') { bp = NULL; continue; } sse = *bp++ - '0'; while (*bp >= '0' && *bp <= '9') { d = *bp++ - '0'; if (sse > TIME_MAX/10) { bp = NULL; break; } sse *= 10; if (sse > TIME_MAX - d) { bp = NULL; break; } sse += d; } if (bp == NULL) continue; if (localtime_r(&sse, tm) == NULL) bp = NULL; else state |= S_YDAY | S_WDAY | S_MON | S_MDAY | S_YEAR; continue; } case 'U': /* The week of year, beginning on sunday. */ case 'W': /* The week of year, beginning on monday. */ /* * This is bogus, as we can not assume any valid * information present in the tm structure at this * point to calculate a real value, so save the * week for now in case it can be used later. */ bp = conv_num(bp, &i, 0, 53); LEGAL_ALT(ALT_O); if (c == 'U') day_offset = TM_SUNDAY; else day_offset = TM_MONDAY; week_offset = i; continue; case 'w': /* The day of week, beginning on sunday. */ bp = conv_num(bp, &tm->tm_wday, 0, 6); LEGAL_ALT(ALT_O); state |= S_WDAY; continue; case 'u': /* The day of week, monday = 1. */ bp = conv_num(bp, &i, 1, 7); tm->tm_wday = i % 7; LEGAL_ALT(ALT_O); state |= S_WDAY; continue; case 'g': /* The year corresponding to the ISO week * number but without the century. */ bp = conv_num(bp, &i, 0, 99); continue; case 'G': /* The year corresponding to the ISO week * number with century. */ do bp++; while (isdigit(*bp)); continue; case 'V': /* The ISO 8601:1988 week number as decimal */ bp = conv_num(bp, &i, 1, 53); continue; case 'Y': /* The year. */ i = TM_YEAR_BASE; /* just for data sanity... */ bp = conv_num(bp, &i, 0, 9999); tm->tm_year = i - TM_YEAR_BASE; LEGAL_ALT(ALT_E); state |= S_YEAR; continue; case 'y': /* The year within 100 years of the epoch. */ /* LEGAL_ALT(ALT_E | ALT_O); */ bp = conv_num(bp, &i, 0, 99); if (split_year) /* preserve century */ i += (tm->tm_year / 100) * 100; else { split_year = 1; if (i <= 68) i = i + 2000 - TM_YEAR_BASE; else i = i + 1900 - TM_YEAR_BASE; } tm->tm_year = i; state |= S_YEAR; continue; case 'Z': case 'z': tzset(); mandatory = c == 'z'; /* * We recognize all ISO 8601 formats: * Z = Zulu time/UTC * [+-]hhmm * [+-]hh:mm * [+-]hh * We recognize all RFC-822/RFC-2822 formats: * UT|GMT * North American : UTC offsets * E[DS]T = Eastern : -4 | -5 * C[DS]T = Central : -5 | -6 * M[DS]T = Mountain: -6 | -7 * P[DS]T = Pacific : -7 | -8 * Nautical/Military * [A-IL-M] = -1 ... -9 (J not used) * [N-Y] = +1 ... +12 * Note: J maybe used to denote non-nautical * local time */ if (mandatory) while (isspace(*bp)) bp++; zname = bp; switch (*bp++) { case 'G': if (*bp++ != 'M') goto namedzone; /*FALLTHROUGH*/ case 'U': if (*bp++ != 'T') goto namedzone; else if (!delim(*bp) && *bp++ != 'C') goto namedzone; /*FALLTHROUGH*/ case 'Z': if (!delim(*bp)) goto namedzone; tm->tm_isdst = 0; #ifdef TM_GMTOFF tm->TM_GMTOFF = 0; #endif #ifdef TM_ZONE tm->TM_ZONE = utc; #endif continue; case '+': neg = 0; break; case '-': neg = 1; break; default: namedzone: bp = zname; /* Nautical / Military style */ if (delim(bp[1]) && ((*bp >= 'A' && *bp <= 'I') || (*bp >= 'L' && *bp <= 'Y'))) { #ifdef TM_GMTOFF /* Argh! No 'J'! */ if (*bp >= 'A' && *bp <= 'I') tm->TM_GMTOFF = (int)*bp - ('A' - 1); else if (*bp >= 'L' && *bp <= 'M') tm->TM_GMTOFF = (int)*bp - 'A'; else if (*bp >= 'N' && *bp <= 'Y') tm->TM_GMTOFF = 'M' - (int)*bp; tm->TM_GMTOFF *= SECSPERHOUR; #endif #ifdef TM_ZONE tm->TM_ZONE = NULL; /* XXX */ #endif bp++; continue; } /* 'J' is local time */ if (delim(bp[1]) && *bp == 'J') { #ifdef TM_GMTOFF tm->TM_GMTOFF = -timezone; #endif #ifdef TM_ZONE tm->TM_ZONE = NULL; /* XXX */ #endif bp++; continue; } /* * From our 3 letter hard-coded table * XXX: Can be removed, handled by tzload() */ if (delim(bp[0]) || delim(bp[1]) || delim(bp[2]) || !delim(bp[3])) goto loadzone; ep = find_string(bp, &i, nast, NULL, 4); if (ep != NULL) { #ifdef TM_GMTOFF tm->TM_GMTOFF = (-5 - i) * SECSPERHOUR; #endif #ifdef TM_ZONE tm->TM_ZONE = __UNCONST(nast[i]); #endif bp = ep; continue; } ep = find_string(bp, &i, nadt, NULL, 4); if (ep != NULL) { tm->tm_isdst = 1; #ifdef TM_GMTOFF tm->TM_GMTOFF = (-4 - i) * SECSPERHOUR; #endif #ifdef TM_ZONE tm->TM_ZONE = __UNCONST(nadt[i]); #endif bp = ep; continue; } /* * Our current timezone */ ep = find_string(bp, &i, (const char * const *)tzname, NULL, 2); if (ep != NULL) { tm->tm_isdst = i; #ifdef TM_GMTOFF tm->TM_GMTOFF = -timezone; #endif #ifdef TM_ZONE tm->TM_ZONE = tzname[i]; #endif bp = ep; continue; } loadzone: /* * The hard way, load the zone! */ if (fromzone(&bp, tm, mandatory)) continue; goto out; } offs = 0; for (i = 0; i < 4; ) { if (isdigit(*bp)) { offs = offs * 10 + (*bp++ - '0'); i++; continue; } if (i == 2 && *bp == ':') { bp++; continue; } break; } if (isdigit(*bp)) goto out; switch (i) { case 2: offs *= SECSPERHOUR; break; case 4: i = offs % 100; offs /= 100; if (i >= SECSPERMIN) goto out; /* Convert minutes into decimal */ offs = offs * SECSPERHOUR + i * SECSPERMIN; break; default: out: if (mandatory) return NULL; bp = zname; continue; } /* ISO 8601 & RFC 3339 limit to 23:59 max */ if (offs >= (HOURSPERDAY * SECSPERHOUR)) goto out; if (neg) offs = -offs; tm->tm_isdst = 0; /* XXX */ #ifdef TM_GMTOFF tm->TM_GMTOFF = offs; #endif #ifdef TM_ZONE tm->TM_ZONE = NULL; /* XXX */ #endif continue; /* * Miscellaneous conversions. */ case 'n': /* Any kind of white-space. */ case 't': while (isspace(*bp)) bp++; LEGAL_ALT(0); continue; default: /* Unknown/unsupported conversion. */ return NULL; } } if (!HAVE_YDAY(state) && HAVE_YEAR(state)) { if (HAVE_MON(state) && HAVE_MDAY(state)) { /* calculate day of year (ordinal date) */ tm->tm_yday = start_of_month[isleap_sum(tm->tm_year, TM_YEAR_BASE)][tm->tm_mon] + (tm->tm_mday - 1); state |= S_YDAY; } else if (day_offset != -1) { /* * Set the date to the first Sunday (or Monday) * of the specified week of the year. */ if (!HAVE_WDAY(state)) { tm->tm_wday = day_offset; state |= S_WDAY; } tm->tm_yday = (7 - first_wday_of(tm->tm_year + TM_YEAR_BASE) + day_offset) % 7 + (week_offset - 1) * 7 + tm->tm_wday - day_offset; state |= S_YDAY; } } if (HAVE_YDAY(state) && HAVE_YEAR(state)) { int isleap; if (!HAVE_MON(state)) { /* calculate month of day of year */ i = 0; isleap = isleap_sum(tm->tm_year, TM_YEAR_BASE); while (tm->tm_yday >= start_of_month[isleap][i]) i++; if (i > 12) { i = 1; tm->tm_yday -= start_of_month[isleap][12]; tm->tm_year++; } tm->tm_mon = i - 1; state |= S_MON; } if (!HAVE_MDAY(state)) { /* calculate day of month */ isleap = isleap_sum(tm->tm_year, TM_YEAR_BASE); tm->tm_mday = tm->tm_yday - start_of_month[isleap][tm->tm_mon] + 1; state |= S_MDAY; } if (!HAVE_WDAY(state)) { /* calculate day of week */ i = 0; week_offset = first_wday_of(tm->tm_year); while (i++ <= tm->tm_yday) { if (week_offset++ >= 6) week_offset = 0; } tm->tm_wday = week_offset; state |= S_WDAY; } } return __UNCONST(bp); } static const u_char * conv_num(const unsigned char *buf, int *dest, uint llim, uint ulim) { uint result = 0; unsigned char ch; /* The limit also determines the number of valid digits. */ uint rulim = ulim; ch = *buf; if (ch < '0' || ch > '9') return NULL; do { result *= 10; result += ch - '0'; rulim /= 10; ch = *++buf; } while ((result * 10 <= ulim) && rulim && ch >= '0' && ch <= '9'); if (result < llim || result > ulim) return NULL; *dest = result; return buf; } static const u_char * find_string(const u_char *bp, int *tgt, const char * const *n1, const char * const *n2, int c) { int i; size_t len; /* check full name - then abbreviated ones */ for (; n1 != NULL; n1 = n2, n2 = NULL) { for (i = 0; i < c; i++, n1++) { len = strlen(*n1); if (strncasecmp(*n1, (const char *)bp, len) == 0) { *tgt = i; return bp + len; } } } /* Nothing matched */ return NULL; }