path: root/library/cpp/regex/glob/glob.cpp

#define FROM_IMPLEMENTATION
#include "glob_compat.h"

#if defined(USE_INTERNAL_GLOB)
/*
 * Copyright (c) 1989, 1993
 *    The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Guido van Rossum.
 *
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by the University of
 *    California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 <library/cpp/charset/ci_string.h>
#include <util/system/compat.h>
#include <util/folder/dirut.h>

/*
 * glob(3) -- a superset of the one defined in POSIX 1003.2.
 *
 * The [!...] convention to negate a range is supported (SysV, Posix, ksh).
 *
 * Optional extra services, controlled by flags not defined by POSIX:
 *
 * GLOB_QUOTE:
 *    Escaping convention: \ inhibits any special meaning the following
 *    character might have (except \ at end of string is retained).
 * GLOB_MAGCHAR:
 *    Set in gl_flags if pattern contained a globbing character.
 * GLOB_NOMAGIC:
 *    Same as GLOB_NOCHECK, but it will only append pattern if it did
 *    not contain any magic characters.  [Used in csh style globbing]
 * GLOB_ALTDIRFUNC:
 *    Use alternately specified directory access functions.
 * GLOB_TILDE:
 *    expand ~user/foo to the /home/dir/of/user/foo
 * GLOB_BRACE:
 *    expand {1,2}{a,b} to 1a 1b 2a 2b
 * gl_matchc:
 *    Number of matches in the current invocation of glob.
 */

/*
 * Some notes on multibyte character support:
 * 1. Patterns with illegal byte sequences match nothing - even if
 *    GLOB_NOCHECK is specified.
 * 2. Illegal byte sequences in filenames are handled by treating them as
 *    single-byte characters with a value of the first byte of the sequence
 *    cast to wchar_t.
 * 3. State-dependent encodings are not currently supported.
 */

//#include <sys/param.h>
#include <sys/stat.h>

#include <ctype.h>
//#include <dirent.h>
#include <errno.h>
#include <limits.h>
//#include <pwd.h>
//#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if defined(_unix_)
#include <unistd.h>
#endif
#include <wchar.h>

#if !defined(_unix_)
// silly replacement for compilation
using uint_fast64_t = ui64;
using u_int = unsigned int;
using u_char = unsigned char;
#define ARG_MAX 256
#define S_ISDIR(x) ((x) & _S_IFDIR)
#define S_ISLNK(x) 0
#define lstat stat
inline bool issetugid() { return false; }
inline char *getlogin() { return 0; }
inline int getuid() { return 0; }
struct passwd {
    char *pw_dir;
};
inline passwd *getpwuid(int) { return 0; }
inline passwd *getpwnam(char *) { return 0; }
#endif

#define __collate_load_error 1
inline int __collate_range_cmp(int, int) { return 0; }
#undef COMMA // was defined in stroka.h
// end silly replacement

//#include "collate.h"

#define    DOLLAR        '$'
#define    DOT        '.'
#define    EOS        '\0'
#define    LBRACKET    '['
#define    NOT        '!'
#define    QUESTION    '?'
#define    QUOTE        '\\'
#define    RANGE        '-'
#define    RBRACKET    ']'
#define    SEP        '/'
#define    STAR        '*'
#define    TILDE        '~'
#define    UNDERSCORE    '_'
#define    LBRACE        '{'
#define    RBRACE        '}'
#define    SLASH        '/'
#define    COMMA        ','

#ifndef DEBUG

#define    M_QUOTE        0x8000000000ULL
#define    M_PROTECT    0x4000000000ULL
#define    M_MASK        0xffffffffffULL
#define    M_CHAR        0x00ffffffffULL

using Char = uint_fast64_t;

#else

#define    M_QUOTE        0x80
#define    M_PROTECT    0x40
#define    M_MASK        0xff
#define    M_CHAR        0x7f

using Char = char;

#endif


#define    CHAR(c)        ((Char)((c)&M_CHAR))
#define    META(c)        ((Char)((c)|M_QUOTE))
#define    M_ALL        META('*')
#define    M_END        META(']')
#define    M_NOT        META('!')
#define    M_ONE        META('?')
#define    M_RNG        META('-')
#define    M_SET        META('[')
#define    ismeta(c)    (((c)&M_QUOTE) != 0)


static int     compare(const void *, const void *);
static int     g_Ctoc(const Char *, char *, u_int);
static int     g_lstat(Char *, struct stat *, glob_t *);
static DIR    *g_opendir(Char *, glob_t *);
static Char    *g_strchr(Char *, wchar_t);
#ifdef notdef
static Char    *g_strcat(Char *, const Char *);
#endif
static int     glob0(const Char *, glob_t *, int *);
static int     glob1(Char *, glob_t *, int *);
static int     glob2(Char *, Char *, Char *, Char *, glob_t *, int *);
static int     glob3(Char *, Char *, Char *, Char *, Char *, glob_t *, int *);
static int     globextend(const Char *, glob_t *, int *);
static const Char *
         globtilde(const Char *, Char *, size_t, glob_t *);
static int     globexp1(const Char *, glob_t *, int *);
static int     globexp2(const Char *, const Char *, glob_t *, int *, int *);
static int     match(Char *, Char *, Char *);
#ifdef DEBUG
static void     qprintf(const char *, Char *);
#endif

int
glob(const char *pattern, int flags, int (*errfunc)(const char *, int), glob_t *pglob)
{
    const u_char *patnext;
    int limit;
    Char *bufnext, *bufend, patbuf[MAXPATHLEN], prot;
    mbstate_t mbs;
    wchar_t wc;
    size_t clen;

    patnext = (u_char *) pattern;
    if (!(flags & GLOB_APPEND)) {
        pglob->gl_pathc = 0;
        pglob->gl_pathv = NULL;
        if (!(flags & GLOB_DOOFFS))
            pglob->gl_offs = 0;
    }
    if (flags & GLOB_LIMIT) {
        limit = pglob->gl_matchc;
        if (limit == 0)
            limit = ARG_MAX;
    } else
        limit = 0;
    pglob->gl_flags = flags & ~GLOB_MAGCHAR;
    pglob->gl_errfunc = errfunc;
    pglob->gl_matchc = 0;

    bufnext = patbuf;
    bufend = bufnext + MAXPATHLEN - 1;
    if (flags & GLOB_NOESCAPE) {
        memset(&mbs, 0, sizeof(mbs));
        while (bufend - bufnext >= MB_CUR_MAX) {
            clen = mbrtowc(&wc, (const char*)patnext, MB_LEN_MAX, &mbs);
            if (clen == (size_t)-1 || clen == (size_t)-2)
                return (GLOB_NOMATCH);
            else if (clen == 0)
                break;
            *bufnext++ = wc;
            patnext += clen;
        }
    } else {
        /* Protect the quoted characters. */
        memset(&mbs, 0, sizeof(mbs));
        while (bufend - bufnext >= MB_CUR_MAX) {
            if (*patnext == QUOTE) {
                if (*++patnext == EOS) {
                    *bufnext++ = QUOTE | M_PROTECT;
                    continue;
                }
                prot = M_PROTECT;
            } else
                prot = 0;
            clen = mbrtowc(&wc, (const char*)patnext, MB_LEN_MAX, &mbs);
            if (clen == (size_t)-1 || clen == (size_t)-2)
                return (GLOB_NOMATCH);
            else if (clen == 0)
                break;
            *bufnext++ = wc | prot;
            patnext += clen;
        }
    }
    *bufnext = EOS;

    if (flags & GLOB_BRACE)
        return globexp1(patbuf, pglob, &limit);
    else
        return glob0(patbuf, pglob, &limit);
}

/*
 * Expand recursively a glob {} pattern. When there is no more expansion
 * invoke the standard globbing routine to glob the rest of the magic
 * characters
 */
static int
globexp1(const Char *pattern, glob_t *pglob, int *limit)
{
    const Char* ptr = pattern;
    int rv;

    /* Protect a single {}, for find(1), like csh */
    if (pattern[0] == LBRACE && pattern[1] == RBRACE && pattern[2] == EOS)
        return glob0(pattern, pglob, limit);

    while ((ptr = (const Char *) g_strchr((Char *) ptr, LBRACE)) != NULL)
        if (!globexp2(ptr, pattern, pglob, &rv, limit))
            return rv;

    return glob0(pattern, pglob, limit);
}


/*
 * Recursive brace globbing helper. Tries to expand a single brace.
 * If it succeeds then it invokes globexp1 with the new pattern.
 * If it fails then it tries to glob the rest of the pattern and returns.
 */
static int
globexp2(const Char *ptr, const Char *pattern, glob_t *pglob, int *rv, int *limit)
{
    int     i;
    Char   *lm, *ls;
    const Char *pe, *pm, *pm1, *pl;
    Char    patbuf[MAXPATHLEN];

    /* copy part up to the brace */
    for (lm = patbuf, pm = pattern; pm != ptr; *lm++ = *pm++)
        continue;
    *lm = EOS;
    ls = lm;

    /* Find the balanced brace */
    for (i = 0, pe = ++ptr; *pe; pe++)
        if (*pe == LBRACKET) {
            /* Ignore everything between [] */
            for (pm = pe++; *pe != RBRACKET && *pe != EOS; pe++)
                continue;
            if (*pe == EOS) {
                /*
                 * We could not find a matching RBRACKET.
                 * Ignore and just look for RBRACE
                 */
                pe = pm;
            }
        }
        else if (*pe == LBRACE)
            i++;
        else if (*pe == RBRACE) {
            if (i == 0)
                break;
            i--;
        }

    /* Non matching braces; just glob the pattern */
    if (i != 0 || *pe == EOS) {
        *rv = glob0(patbuf, pglob, limit);
        return 0;
    }

    for (i = 0, pl = pm = ptr; pm <= pe; pm++)
        switch (*pm) {
        case LBRACKET:
            /* Ignore everything between [] */
            for (pm1 = pm++; *pm != RBRACKET && *pm != EOS; pm++)
                continue;
            if (*pm == EOS) {
                /*
                 * We could not find a matching RBRACKET.
                 * Ignore and just look for RBRACE
                 */
                pm = pm1;
            }
            break;

        case LBRACE:
            i++;
            break;

        case RBRACE:
            if (i) {
                i--;
                break;
            }
            [[fallthrough]];
        case COMMA:
            if (i && *pm == COMMA)
                break;
            else {
                /* Append the current string */
                for (lm = ls; (pl < pm); *lm++ = *pl++)
                    continue;
                /*
                 * Append the rest of the pattern after the
                 * closing brace
                 */
                for (pl = pe + 1; (*lm++ = *pl++) != EOS;)
                    continue;

                /* Expand the current pattern */
#ifdef DEBUG
                qprintf("globexp2:", patbuf);
#endif
                *rv = globexp1(patbuf, pglob, limit);

                /* move after the comma, to the next string */
                pl = pm + 1;
            }
            break;

        default:
            break;
        }
    *rv = 0;
    return 0;
}



/*
 * expand tilde from the passwd file.
 */
static const Char *
globtilde(const Char *pattern, Char *patbuf, size_t patbuf_len, glob_t *pglob)
{
    struct passwd *pwd;
    char *h;
    const Char *p;
    Char *b, *eb;

    if (*pattern != TILDE || !(pglob->gl_flags & GLOB_TILDE))
        return pattern;

    /*
     * Copy up to the end of the string or /
     */
    eb = &patbuf[patbuf_len - 1];
    for (p = pattern + 1, h = (char *) patbuf;
        h < (char *)eb && *p && *p != SLASH; *h++ = (char)*p++)
        continue;

    *h = EOS;

    if (((char *) patbuf)[0] == EOS) {
        /*
         * handle a plain ~ or ~/ by expanding $HOME first (iff
         * we're not running setuid or setgid) and then trying
         * the password file
         */
        if (issetugid() != 0 ||
            (h = ::getenv("HOME")) == NULL) {
            if (((h = getlogin()) != NULL &&
                 (pwd = getpwnam(h)) != NULL) ||
                (pwd = getpwuid(getuid())) != NULL)
                h = pwd->pw_dir;
            else
                return pattern;
        }
    }
    else {
        /*
         * Expand a ~user
         */
        if ((pwd = getpwnam((char*) patbuf)) == NULL)
            return pattern;
        else
            h = pwd->pw_dir;
    }

    /* Copy the home directory */
    for (b = patbuf; b < eb && *h; *b++ = *h++)
        continue;

    /* Append the rest of the pattern */
    while (b < eb && (*b++ = *p++) != EOS)
        continue;
    *b = EOS;

    return patbuf;
}


/*
 * The main glob() routine: compiles the pattern (optionally processing
 * quotes), calls glob1() to do the real pattern matching, and finally
 * sorts the list (unless unsorted operation is requested).  Returns 0
 * if things went well, nonzero if errors occurred.
 */
static int
glob0(const Char *pattern, glob_t *pglob, int *limit)
{
    const Char *qpatnext;
    int c, err, oldpathc;
    Char *bufnext, patbuf[MAXPATHLEN];

    qpatnext = globtilde(pattern, patbuf, MAXPATHLEN, pglob);
    oldpathc = pglob->gl_pathc;
    bufnext = patbuf;

    /* We don't need to check for buffer overflow any more. */
    while ((c = (char)*qpatnext++) != EOS) {
        switch (c) {
        case LBRACKET:
            c = (char)*qpatnext;
            if (c == NOT)
                ++qpatnext;
            if (*qpatnext == EOS ||
                g_strchr((Char *) qpatnext+1, RBRACKET) == NULL) {
                *bufnext++ = LBRACKET;
                if (c == NOT)
                    --qpatnext;
                break;
            }
            *bufnext++ = M_SET;
            if (c == NOT)
                *bufnext++ = M_NOT;
            c = (char)*qpatnext++;
            do {
                *bufnext++ = CHAR(c);
                if (*qpatnext == RANGE &&
                    (c = (char)qpatnext[1]) != RBRACKET) {
                    *bufnext++ = M_RNG;
                    *bufnext++ = CHAR(c);
                    qpatnext += 2;
                }
            } while ((c = (char)*qpatnext++) != RBRACKET);
            pglob->gl_flags |= GLOB_MAGCHAR;
            *bufnext++ = M_END;
            break;
        case QUESTION:
            pglob->gl_flags |= GLOB_MAGCHAR;
            *bufnext++ = M_ONE;
            break;
        case STAR:
            pglob->gl_flags |= GLOB_MAGCHAR;
            /* collapse adjacent stars to one,
             * to avoid exponential behavior
             */
            if (bufnext == patbuf || bufnext[-1] != M_ALL)
                *bufnext++ = M_ALL;
            break;
        default:
            *bufnext++ = CHAR(c);
            break;
        }
    }
    *bufnext = EOS;
#ifdef DEBUG
    qprintf("glob0:", patbuf);
#endif

    if ((err = glob1(patbuf, pglob, limit)) != 0)
        return(err);

    /*
     * If there was no match we are going to append the pattern
     * if GLOB_NOCHECK was specified or if GLOB_NOMAGIC was specified
     * and the pattern did not contain any magic characters
     * GLOB_NOMAGIC is there just for compatibility with csh.
     */
    if (pglob->gl_pathc == oldpathc) {
        if (((pglob->gl_flags & GLOB_NOCHECK) ||
            ((pglob->gl_flags & GLOB_NOMAGIC) &&
            !(pglob->gl_flags & GLOB_MAGCHAR))))
            return(globextend(pattern, pglob, limit));
        else
            return(GLOB_NOMATCH);
    }
    if (!(pglob->gl_flags & GLOB_NOSORT))
        qsort(pglob->gl_pathv + pglob->gl_offs + oldpathc,
            pglob->gl_pathc - oldpathc, sizeof(char *), compare);
    return(0);
}

static int
compare(const void *p, const void *q)
{
    return(strcmp(*(char **)p, *(char **)q));
}

static int
glob1(Char *pattern, glob_t *pglob, int *limit)
{
    Char pathbuf[MAXPATHLEN];

    /* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */
    if (*pattern == EOS)
        return(0);
    return(glob2(pathbuf, pathbuf, pathbuf + MAXPATHLEN - 1,
        pattern, pglob, limit));
}

/*
 * The functions glob2 and glob3 are mutually recursive; there is one level
 * of recursion for each segment in the pattern that contains one or more
 * meta characters.
 */
static int
glob2(Char *pathbuf, Char *pathend, Char *pathend_last, Char *pattern, glob_t *pglob, int *limit)
{
    struct stat sb;
    Char *p, *q;
    int anymeta;

    /*
     * Loop over pattern segments until end of pattern or until
     * segment with meta character found.
     */
    for (anymeta = 0;;) {
        if (*pattern == EOS) {        /* End of pattern? */
            *pathend = EOS;
            if (g_lstat(pathbuf, &sb, pglob))
                return(0);

            if (((pglob->gl_flags & GLOB_MARK) &&
                pathend[-1] != SEP) && (S_ISDIR(sb.st_mode))) {
                if (pathend + 1 > pathend_last)
                    return (GLOB_ABORTED);
                *pathend++ = SEP;
                *pathend = EOS;
            }
            ++pglob->gl_matchc;
            return(globextend(pathbuf, pglob, limit));
        }

        /* Find end of next segment, copy tentatively to pathend. */
        q = pathend;
        p = pattern;
        while (*p != EOS && *p != SEP) {
            if (ismeta(*p))
                anymeta = 1;
            if (q + 1 > pathend_last)
                return (GLOB_ABORTED);
            *q++ = *p++;
        }

        if (!anymeta) {        /* No expansion, do next segment. */
            pathend = q;
            pattern = p;
            while (*pattern == SEP) {
                if (pathend + 1 > pathend_last)
                    return (GLOB_ABORTED);
                *pathend++ = *pattern++;
            }
        } else            /* Need expansion, recurse. */
            return(glob3(pathbuf, pathend, pathend_last, pattern, p,
                pglob, limit));
    }
    /* NOTREACHED */
}

static int
glob3(Char *pathbuf, Char *pathend, Char *pathend_last, Char *pattern, Char *restpattern, glob_t *pglob, int *limit)
{
    struct dirent *dp;
    DIR *dirp;
    int err;
    char buf[MAXPATHLEN];

    /*
     * The readdirfunc declaration can't be prototyped, because it is
     * assigned, below, to two functions which are prototyped in glob.h
     * and dirent.h as taking pointers to differently typed opaque
     * structures.
     */
    typedef struct dirent *(*readdirfunc_t)(void*);
    readdirfunc_t readdirfunc;

    if (pathend > pathend_last)
        return (GLOB_ABORTED);
    *pathend = EOS;
    errno = 0;

    if ((dirp = g_opendir(pathbuf, pglob)) == NULL) {
        /* TODO: don't call for ENOENT or ENOTDIR? */
        if (pglob->gl_errfunc) {
            if (g_Ctoc(pathbuf, buf, sizeof(buf)))
                return (GLOB_ABORTED);
            if (pglob->gl_errfunc(buf, errno) ||
                pglob->gl_flags & GLOB_ERR)
                return (GLOB_ABORTED);
        }
        return(0);
    }

    err = 0;

    /* Search directory for matching names. */
    if (pglob->gl_flags & GLOB_ALTDIRFUNC)
        readdirfunc = pglob->gl_readdir;
    else
        readdirfunc = (readdirfunc_t)readdir;
    while ((dp = (*readdirfunc)(dirp))) {
        u_char *sc;
        Char *dc;
        wchar_t wc;
        size_t clen;
        mbstate_t mbs;

        /* Initial DOT must be matched literally. */
        if (dp->d_name[0] == DOT && *pattern != DOT)
            continue;
        memset(&mbs, 0, sizeof(mbs));
        dc = pathend;
        sc = (u_char *) dp->d_name;
        while (dc < pathend_last) {
            clen = mbrtowc(&wc, (const char*)sc, MB_LEN_MAX, &mbs);
            if (clen == (size_t)-1 || clen == (size_t)-2) {
                wc = *sc;
                clen = 1;
                memset(&mbs, 0, sizeof(mbs));
            }
            if ((*dc++ = wc) == EOS)
                break;
            sc += clen;
        }
        if (!match(pathend, pattern, restpattern)) {
            *pathend = EOS;
            continue;
        }
        err = glob2(pathbuf, --dc, pathend_last, restpattern,
            pglob, limit);
        if (err)
            break;
    }

    if (pglob->gl_flags & GLOB_ALTDIRFUNC)
        (*pglob->gl_closedir)(dirp);
    else
        closedir(dirp);
    return(err);
}


/*
 * Extend the gl_pathv member of a glob_t structure to accomodate a new item,
 * add the new item, and update gl_pathc.
 *
 * This assumes the BSD realloc, which only copies the block when its size
 * crosses a power-of-two boundary; for v7 realloc, this would cause quadratic
 * behavior.
 *
 * Return 0 if new item added, error code if memory couldn't be allocated.
 *
 * Invariant of the glob_t structure:
 *    Either gl_pathc is zero and gl_pathv is NULL; or gl_pathc > 0 and
 *    gl_pathv points to (gl_offs + gl_pathc + 1) items.
 */
static int
globextend(const Char *path, glob_t *pglob, int *limit)
{
    char **pathv;
    int i;
    size_t newsize, len;
    char *copy;
    const Char *p;

    if (*limit && pglob->gl_pathc > *limit) {
        errno = 0;
        return (GLOB_NOSPACE);
    }

    newsize = sizeof(*pathv) * (2 + pglob->gl_pathc + pglob->gl_offs);
    pathv = pglob->gl_pathv ?
            (char**)realloc((char *)pglob->gl_pathv, newsize) :
            (char**)malloc(newsize);
    if (pathv == NULL) {
        if (pglob->gl_pathv) {
            free(pglob->gl_pathv);
            pglob->gl_pathv = NULL;
        }
        return(GLOB_NOSPACE);
    }

    if (pglob->gl_pathv == NULL && pglob->gl_offs > 0) {
        /* first time around -- clear initial gl_offs items */
        pathv += pglob->gl_offs;
        for (i = pglob->gl_offs; --i >= 0; )
            *--pathv = NULL;
    }
    pglob->gl_pathv = pathv;

    for (p = path; *p++;)
        continue;
    len = MB_CUR_MAX * (size_t)(p - path);    /* XXX overallocation */
    if ((copy = (char*)malloc(len)) != NULL) {
        if (g_Ctoc(path, copy, (u_int)len)) {
            free(copy);
            return (GLOB_NOSPACE);
        }
        pathv[pglob->gl_offs + pglob->gl_pathc++] = copy;
    }
    pathv[pglob->gl_offs + pglob->gl_pathc] = NULL;
    return(copy == NULL ? GLOB_NOSPACE : 0);
}

/*
 * pattern matching function for filenames.  Each occurrence of the *
 * pattern causes a recursion level.
 */
static int
match(Char *name, Char *pat, Char *patend)
{
    int ok, negate_range;
    Char c, k;

    while (pat < patend) {
        c = *pat++;
        switch (c & M_MASK) {
        case M_ALL:
            if (pat == patend)
                return(1);
            do
                if (match(name, pat, patend))
                    return(1);
            while (*name++ != EOS);
            return(0);
        case M_ONE:
            if (*name++ == EOS)
                return(0);
            break;
        case M_SET:
            ok = 0;
            if ((k = *name++) == EOS)
                return(0);
            if ((negate_range = ((*pat & M_MASK) == M_NOT)) != EOS)
                ++pat;
            while (((c = *pat++) & M_MASK) != M_END)
                if ((*pat & M_MASK) == M_RNG) {
                    if (__collate_load_error ?
                        CHAR(c) <= CHAR(k) && CHAR(k) <= CHAR(pat[1]) :
                           __collate_range_cmp((int)CHAR(c), (int)CHAR(k)) <= 0
                        && __collate_range_cmp((int)CHAR(k), (int)CHAR(pat[1])) <= 0
                       )
                        ok = 1;
                    pat += 2;
                } else if (c == k)
                    ok = 1;
            if (ok == negate_range)
                return(0);
            break;
        default:
            if (*name++ != c)
                return(0);
            break;
        }
    }
    return(*name == EOS);
}

/* Free allocated data belonging to a glob_t structure. */
void
globfree(glob_t *pglob)
{
    int i;
    char **pp;

    if (pglob->gl_pathv != NULL) {
        pp = pglob->gl_pathv + pglob->gl_offs;
        for (i = pglob->gl_pathc; i--; ++pp)
            if (*pp)
                free(*pp);
        free(pglob->gl_pathv);
        pglob->gl_pathv = NULL;
    }
}

static DIR *
g_opendir(Char *str, glob_t *pglob)
{
    char buf[MAXPATHLEN];

    if (!*str)
        strcpy(buf, ".");
    else {
        if (g_Ctoc(str, buf, sizeof(buf)))
            return (NULL);
    }

    if (pglob->gl_flags & GLOB_ALTDIRFUNC)
        return (DIR*)((*pglob->gl_opendir)(buf));

    return(opendir(buf));
}

static int
g_lstat(Char *fn, struct stat *sb, glob_t *pglob)
{
    char buf[MAXPATHLEN];

    if (g_Ctoc(fn, buf, sizeof(buf))) {
        errno = ENAMETOOLONG;
        return (-1);
    }
    if (pglob->gl_flags & GLOB_ALTDIRFUNC)
        return((*pglob->gl_lstat)(buf, sb));
    return(lstat(buf, sb));
}

static Char *
g_strchr(Char *str, wchar_t ch)
{
    do {
        if (*str == ch)
            return (str);
    } while (*str++);
    return (NULL);
}

static int
g_Ctoc(const Char *str, char *buf, u_int len)
{
    mbstate_t mbs;
    size_t clen;

    memset(&mbs, 0, sizeof(mbs));
    while ((int)len >= MB_CUR_MAX) {
        clen = wcrtomb(buf, (wchar_t)*str, &mbs);
        if (clen == (size_t)-1)
            return (1);
        if (*str == L'\0')
            return (0);
        str++;
        buf += clen;
        len -= (u_int)clen;
    }
    return (1);
}

#ifdef DEBUG
static void
qprintf(const char *str, Char *s)
{
    Char *p;

    (void)printf("%s:\n", str);
    for (p = s; *p; p++)
        (void)printf("%c", CHAR(*p));
    (void)printf("\n");
    for (p = s; *p; p++)
        (void)printf("%c", *p & M_PROTECT ? '"' : ' ');
    (void)printf("\n");
    for (p = s; *p; p++)
        (void)printf("%c", ismeta(*p) ? '_' : ' ');
    (void)printf("\n");
}
#endif
#endif