/*      $NetBSD: strptime.c,v 1.68 2026/06/22 14:37:29 wiz 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 <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: strptime.c,v 1.68 2026/06/22 14:37:29 wiz Exp $");
#endif

#include "namespace.h"
#include <sys/localedef.h>
#include <sys/types.h>
#include <ctype.h>
#include <locale.h>
#include <string.h>
#include <time.h>
#include <tzfile.h>
#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[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 (1 +
                5 * ((yr - 1) % 4) +
                4 * ((yr - 1) % 100) +
                6 * ((yr - 1) % 400)) % 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 */
                        week_offset = first_wday_of(tm->tm_year +
                                                    TM_YEAR_BASE);
                        tm->tm_wday = (week_offset + tm->tm_yday) % 7;
                        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;
}