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Diffstat (limited to '')
| -rw-r--r-- | wsutil/ws_strptime.c | 906 |
1 files changed, 906 insertions, 0 deletions
diff --git a/wsutil/ws_strptime.c b/wsutil/ws_strptime.c new file mode 100644 index 0000000..3c55d93 --- /dev/null +++ b/wsutil/ws_strptime.c @@ -0,0 +1,906 @@ +/*- + * 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. + */ +#define _GNU_SOURCE +#include "config.h" +#include "ws_strptime.h" +#include <time.h> +#include <wsutil/time_util.h> /* For ws_localtime_r() */ +#include <wsutil/strtoi.h> + +#ifdef _WIN32 +#define tzset _tzset +#define tzname _tzname +#define timezone _timezone +#define daylight _daylight +#endif + +static const unsigned char *conv_num(const unsigned char *, int *, unsigned, unsigned); +static const unsigned char *find_string(const unsigned char *, int *, const char * const *, + const char * const *, int); + +#define SECSPERMIN 60 +#define MINSPERHOUR 60 +#define HOURSPERDAY 24 +#define DAYSPERWEEK 7 +#define DAYSPERNYEAR 365 +#define DAYSPERLYEAR 366 +#define SECSPERHOUR (SECSPERMIN * MINSPERHOUR) +#define SECSPERDAY ((int_fast32_t) SECSPERHOUR * HOURSPERDAY) +#define MONSPERYEAR 12 + +#define TM_SUNDAY 0 +#define TM_MONDAY 1 +#define TM_TUESDAY 2 +#define TM_WEDNESDAY 3 +#define TM_THURSDAY 4 +#define TM_FRIDAY 5 +#define TM_SATURDAY 6 + +#define TM_JANUARY 0 +#define TM_FEBRUARY 1 +#define TM_MARCH 2 +#define TM_APRIL 3 +#define TM_MAY 4 +#define TM_JUNE 5 +#define TM_JULY 6 +#define TM_AUGUST 7 +#define TM_SEPTEMBER 8 +#define TM_OCTOBER 9 +#define TM_NOVEMBER 10 +#define TM_DECEMBER 11 + +#define TM_YEAR_BASE 1900 + +#define EPOCH_YEAR 1970 +#define EPOCH_WDAY TM_THURSDAY + +#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0)) + +/* +** Since everything in isleap is modulo 400 (or a factor of 400), we know that +** isleap(y) == isleap(y % 400) +** and so +** isleap(a + b) == isleap((a + b) % 400) +** or +** isleap(a + b) == isleap(a % 400 + b % 400) +** This is true even if % means modulo rather than Fortran remainder +** (which is allowed by C89 but not C99). +** We use this to avoid addition overflow problems. +*/ + +#define isleap_sum(a, b) isleap((a) % 400 + (b) % 400) + +/* + * 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" +}; + +static const char * const cloc_am_pm[] = {"AM", "PM", NULL}; + +static const char * const cloc_abday[] = { + "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", NULL +}; + +static const char * const cloc_day[] = { + "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", + "Saturday", NULL +}; + +static const char * const cloc_abmon[] = { + "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", + "Oct", "Nov", "Dec", NULL +}; + +static const char * const cloc_mon[] = { + "January", "February", "March", "April", "May", "June", "July", + "August", "September", "October", "November", "December", NULL +}; + +/* + * 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' || g_ascii_isspace((unsigned char)(p))) + +#define SET_ZONEP(p, off, zone) \ + do { if (p) { p->tm_gmtoff = off; p->tm_zone = zone; } } while (0) + +/* + * This is spectacularly ugly. + * + * POSIX require that there be a variable named "timezone", which contains + * "the difference, in seconds, between Coordinated Universal Time (UTC) + * and local standard time.". + * + * Most of the platforms on which we run have this. + * + * FreeBSD, however, does not. Instead, it provides a function named + * "timezone", which takes two integer arguments, "zone" and "dst", + * and "returns a pointer to a time zone abbreviation for the specified + * zone and dst values. The zone argument is the number of minutes west + * of GMT and dst is non-zero if daylight savings time is in effect." + * + * So we need a way to get "the difference, in seconds, between Coordinated + * Universal Time (UTC) and local standard time." + * + * The FreeBSD Wireshark port, as of 2023-12-05, does so by handing + * a time_t value of 0, meaning 1970-01-01 00:00:00 UTC (the Unix Epoch), + * to localtime() and using the tm_gmtoff value from the resulting + * struct tm. That works in countries that were in standard time + * then, but doesn't work in countries that were not in standard time + * then, meaning it doesn't work correctly in countries in the Southern + * Hemisphere that were in Daylight Saving Tie at that point, and may or + * may not work correctly in Ireland, depending on how "standard time" + * is defined (don't ask). + * + * For now, we use a similar mechanism to the one above, but we check + * whether tm_isdst is greater than 0 in the resulting struct tm and, + * if it is, use a time_t value of 86400*(365/2), in the hopes that, + * halfway through 1970, the location in question was in standard + * time. + * + * Also, for now, we test for FreeBSD rather than doing a configure- + * time check; checking whether the symbol "timezone" is defined + * won't work, as it's defined in FreeBSD as a function, so we'd + * have to check *how* it's defined. + * + * So we have a function to return the difference in question. It + * returns a long because timezone is defined to be a long in POSIX + * and because the tm_gmtoff member of a struct tm, if such a member + * is present, is also a long. + */ +static long +utc_offset(void) +{ +#if defined(__FreeBSD__) + /* + * We only calculate the standard time UTC offset once, under the + * assumption that we won't change what time zone we're in. + * + * XXX - that assumption is violated if: + * + * you're running on an OS where you can set the current + * time zone and that will affect all running programs, + * or where the OS tries to determine where you're located + * and changes the time zone to match (for example, macOS, + * in which both of those are the case); + * + * you're in a location that has moved between time zones + * since 1970-01-01 00:00:00 UTC (there are some, and the + * IANA time zone database, at least, takes that into + * account); + * + * we add support for the if_iana_tzname Interface + * Description Block option, so that, when looking + * at a file with that option for one or more + * interfaces, and using the timezone from that + * option rather than the local timezone, the + * offset from UTC may change from file to file. + * + * This *probably* won't make much of a difference, as + * we have to do this sort of hackery only when parsing + * a date that doesn't use the "Obsolete Date and Time", + * as it's called in RFC 2822. + */ + static bool got_utcoffset = false; + static struct tm *gtm; + time_t then = 0; + + if (got_utcoffset) { + if (gtm != NULL) + return gtm->tm_gmtoff; + else + return 0; /* localtime() failed on us */ + } + + gtm = localtime(&then); + got_utcoffset = true; + if (gtm == NULL) { + /* + * Oh, heck, it can't convert the Epoch. Just + * return 0 and say to hell with it. + */ + return 0; + } + if (gtm->tm_isdst > 0) { + /* + * Sorry, we were in Daylight Saving Time on + * 1970-01-01 at 00:00:00 UTC. Try the middle + * of the year. (We don't bother making sure + * we weren't in DST then.) + */ + then = 86400*(365/2); + gtm = localtime(&then); + if (gtm == NULL) { + /* See above. */ + return 0; + } + } + return gtm->tm_gmtoff; +#else + return timezone; +#endif +} + +char * +ws_strptime_p(const char *buf, const char *format, struct tm *tm) +{ +#ifdef HAVE_STRPTIME + return strptime(buf, format, tm); +#else + return ws_strptime(buf, format, tm, NULL); +#endif +} + +char * +ws_strptime(const char *buf, const char *fmt, struct tm *tm, struct ws_timezone *zonep) +{ + 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; + long tm_gmtoff; + const char *tm_zone; + + bp = (const unsigned 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 (g_ascii_isspace(c)) { + while (g_ascii_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 = "%a %b %e %H:%M:%S %Y"; + 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 = "%I:%M:%S %p"; + 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 = "%H:%M:%S"; + goto recurse; + + case 'x': /* The date, using the locale's format. */ + new_fmt = "%m/%d/%y"; + state |= S_MON | S_MDAY | S_YEAR; + recurse: + bp = (const unsigned char *)ws_strptime((const char *)bp, + new_fmt, tm, zonep); + 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, cloc_day, cloc_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, cloc_mon, cloc_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, cloc_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 */ + { + int64_t secs; + const char *endptr; + time_t sse; + + /* Extract the seconds as a 64-bit signed number. */ + if (!ws_strtoi64(bp, &endptr, &secs)) { + bp = NULL; + continue; + } + bp = endptr; + + /* For now, reject times before the Epoch. */ + if (secs < 0) { + bp = NULL; + continue; + } + + /* Make sure it fits. */ + sse = (time_t)secs; + if (sse != secs) { + bp = NULL; + continue; + } + + if (ws_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 (g_ascii_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 (g_ascii_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; + tm_gmtoff = 0; + tm_zone = utc; + SET_ZONEP(zonep, tm_gmtoff, tm_zone); + 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'))) { + /* Argh! No 'J'! */ + if (*bp >= 'A' && *bp <= 'I') + tm_gmtoff = + (int)*bp - ('A' - 1); + else if (*bp >= 'L' && *bp <= 'M') + tm_gmtoff = (int)*bp - 'A'; + else if (*bp >= 'N' && *bp <= 'Y') + tm_gmtoff = 'M' - (int)*bp; + else { + /* Not reached. */ + ws_critical("Not reached!"); + goto out; + } + tm_gmtoff *= SECSPERHOUR; + tm_zone = NULL; /* XXX */ + SET_ZONEP(zonep, tm_gmtoff, tm_zone); + bp++; + continue; + } + /* 'J' is local time */ + if (delim(bp[1]) && *bp == 'J') { + tm_gmtoff = -utc_offset(); + tm_zone = NULL; /* XXX */ + SET_ZONEP(zonep, tm_gmtoff, tm_zone); + bp++; + continue; + } + + /* + * From our 3 letter hard-coded table + */ + ep = find_string(bp, &i, nast, NULL, 4); + if (ep != NULL) { + tm_gmtoff = (-5 - i) * SECSPERHOUR; + tm_zone = nast[i]; + SET_ZONEP(zonep, tm_gmtoff, tm_zone); + bp = ep; + continue; + } + ep = find_string(bp, &i, nadt, NULL, 4); + if (ep != NULL) { + tm->tm_isdst = 1; + tm_gmtoff = (-4 - i) * SECSPERHOUR; + tm_zone = nadt[i]; + SET_ZONEP(zonep, tm_gmtoff, tm_zone); + bp = ep; + continue; + } + /* + * Our current timezone + */ + ep = find_string(bp, &i, + (const char * const *)tzname, + NULL, 2); + if (ep != NULL) { + tm->tm_isdst = i; + tm_gmtoff = -utc_offset(); + tm_zone = tzname[i]; + SET_ZONEP(zonep, tm_gmtoff, tm_zone); + bp = ep; + continue; + } + goto out; + } + offs = 0; + for (i = 0; i < 4; ) { + if (g_ascii_isdigit(*bp)) { + offs = offs * 10 + (*bp++ - '0'); + i++; + continue; + } + if (i == 2 && *bp == ':') { + bp++; + continue; + } + break; + } + if (g_ascii_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 */ + tm_gmtoff = offs; + tm_zone = NULL; /* XXX */ + SET_ZONEP(zonep, tm_gmtoff, tm_zone); + continue; + + /* + * Miscellaneous conversions. + */ + case 'n': /* Any kind of white-space. */ + case 't': + while (g_ascii_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; + } + } + + return (char *)bp; +} + + +static const unsigned char * +conv_num(const unsigned char *buf, int *dest, unsigned llim, unsigned ulim) +{ + unsigned result = 0; + unsigned char ch; + + /* The limit also determines the number of valid digits. */ + unsigned 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 unsigned char * +find_string(const unsigned 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 (g_ascii_strncasecmp(*n1, (const char *)bp, len) == 0) { + *tgt = i; + return bp + len; + } + } + } + + /* Nothing matched */ + return NULL; +} |