/*  $OpenBSD: glob.c,v 1.49 2020/04/21 08:25:22 dtucker Exp $ */

/*

 * 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. 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.

 */

/* OPENBSD ORIGINAL: lib/libc/gen/glob.c */

/*

 * 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.

 */

#include "includes.h"

#include "glob.h"

#include <sys/types.h>

#include <sys/stat.h>

#include <dirent.h>

#include <ctype.h>

#include <errno.h>

#include <limits.h>

#include <pwd.h>

#include <stdlib.h>

#include <stdint.h>

#include <string.h>

#include <unistd.h>

#if !defined(HAVE_GLOB) || !defined(GLOB_HAS_ALTDIRFUNC) || \

    !defined(GLOB_HAS_GL_MATCHC) || !defined(GLOB_HAS_GL_STATV) || \

    !defined(HAVE_DECL_GLOB_NOMATCH) || HAVE_DECL_GLOB_NOMATCH == 0 || \

    defined(BROKEN_GLOB)

#include "charclass.h"

#ifdef TILDE

# undef TILDE

#endif

#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   0x8000

#define M_PROTECT 0x4000

#define M_MASK    0xffff

#define M_ASCII   0x00ff

typedef u_short Char;

#else

#define M_QUOTE   0x80

#define M_PROTECT 0x40

#define M_MASK    0xff

#define M_ASCII   0x7f

typedef char Char;

#endif

#define CHAR(c)   ((Char)((c)&M_ASCII))

#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 M_CLASS   META(':')

#define ismeta(c) (((c)&M_QUOTE) != 0)

#define GLOB_LIMIT_MALLOC 65536

#define GLOB_LIMIT_STAT   2048

#define GLOB_LIMIT_READDIR  16384

struct glob_lim {

  size_t  glim_malloc;

  size_t  glim_stat;

  size_t  glim_readdir;

};

struct glob_path_stat {

  char    *gps_path;

  struct stat *gps_stat;

};

static int   compare(const void *, const void *);

static int   compare_gps(const void *, const void *);

static int   g_Ctoc(const Char *, char *, size_t);

static int   g_lstat(Char *, struct stat *, glob_t *);

static DIR  *g_opendir(Char *, glob_t *);

static Char *g_strchr(const Char *, int);

static int   g_strncmp(const Char *, const char *, size_t);

static int   g_stat(Char *, struct stat *, glob_t *);

static int   glob0(const Char *, glob_t *, struct glob_lim *);

static int   glob1(Char *, Char *, glob_t *, struct glob_lim *);

static int   glob2(Char *, Char *, Char *, Char *, Char *, Char *,

        glob_t *, struct glob_lim *);

static int   glob3(Char *, Char *, Char *, Char *, Char *,

        Char *, Char *, glob_t *, struct glob_lim *);

static int   globextend(const Char *, glob_t *, struct glob_lim *,

        struct stat *);

static const Char *

     globtilde(const Char *, Char *, size_t, glob_t *);

static int   globexp1(const Char *, glob_t *, struct glob_lim *);

static int   globexp2(const Char *, const Char *, glob_t *,

        struct glob_lim *);

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 c;

  Char *bufnext, *bufend, patbuf[PATH_MAX];

  struct glob_lim limit = { 0, 0, 0 };

  patnext = (u_char *) pattern;

  if (!(flags & GLOB_APPEND)) {

    pglob->gl_pathc = 0;

    pglob->gl_pathv = NULL;

    pglob->gl_statv = NULL;

    if (!(flags & GLOB_DOOFFS))

      pglob->gl_offs = 0;

  }

  pglob->gl_flags = flags & ~GLOB_MAGCHAR;

  pglob->gl_errfunc = errfunc;

  pglob->gl_matchc = 0;

  if (strnlen(pattern, PATH_MAX) == PATH_MAX)

    return(GLOB_NOMATCH);

  if (pglob->gl_offs >= SSIZE_MAX || pglob->gl_pathc >= SSIZE_MAX ||

      pglob->gl_pathc >= SSIZE_MAX - pglob->gl_offs - 1)

    return GLOB_NOSPACE;

  bufnext = patbuf;

  bufend = bufnext + PATH_MAX - 1;

  if (flags & GLOB_NOESCAPE)

    while (bufnext < bufend && (c = *patnext++) != EOS)

      *bufnext++ = c;

  else {

    /* Protect the quoted characters. */

    while (bufnext < bufend && (c = *patnext++) != EOS)

      if (c == QUOTE) {

        if ((c = *patnext++) == EOS) {

          c = QUOTE;

          --patnext;

        }

        *bufnext++ = c | M_PROTECT;

      } else

        *bufnext++ = c;

  }

  *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, struct glob_lim *limitp)

{

  const Char* ptr = pattern;

  /* Protect a single {}, for find(1), like csh */

  if (pattern[0] == LBRACE && pattern[1] == RBRACE && pattern[2] == EOS)

    return glob0(pattern, pglob, limitp);

  if ((ptr = (const Char *) g_strchr(ptr, LBRACE)) != NULL)

    return globexp2(ptr, pattern, pglob, limitp);

  return glob0(pattern, pglob, limitp);

}

/*

 * 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,

    struct glob_lim *limitp)

{

  int     i, rv;

  Char   *lm, *ls;

  const Char *pe, *pm, *pl;

  Char    patbuf[PATH_MAX];

  /* copy part up to the brace */

  for (lm = patbuf, pm = pattern; pm != ptr; *lm++ = *pm++)

    ;

  *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++)

        ;

      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)

    return glob0(patbuf, pglob, limitp);

  for (i = 0, pl = pm = ptr; pm <= pe; pm++) {

    switch (*pm) {

    case LBRACKET:

      /* Ignore everything between [] */

      for (pl = pm++; *pm != RBRACKET && *pm != EOS; pm++)

        ;

      if (*pm == EOS) {

        /*

         * We could not find a matching RBRACKET.

         * Ignore and just look for RBRACE

         */

        pm = pl;

      }

      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++)

          ;

        /*

         * Append the rest of the pattern after the

         * closing brace

         */

        for (pl = pe + 1; (*lm++ = *pl++) != EOS; )

          ;

        /* Expand the current pattern */

#ifdef DEBUG

        qprintf("globexp2:", patbuf);

#endif

        rv = globexp1(patbuf, pglob, limitp);

        if (rv && rv != GLOB_NOMATCH)

          return rv;

        /* move after the comma, to the next string */

        pl = pm + 1;

      }

      break;

    default:

      break;

    }

  }

  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++ = *p++)

    ;

  *h = EOS;

#if 0

  if (h == (char *)eb)

    return what;

#endif

  if (((char *) patbuf)[0] == EOS) {

    /*

     * handle a plain ~ or ~/ by expanding $HOME

     * first and then trying the password file

     */

#if 0

    if (issetugid() != 0 || (h = getenv("HOME")) == NULL) {

#endif

    if ((getuid() != geteuid()) || (h = getenv("HOME")) == NULL) {

      if ((pwd = getpwuid(getuid())) == NULL)

        return pattern;

      else

        h = pwd->pw_dir;

    }

  } 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++)

    ;

  /* Append the rest of the pattern */

  while (b < eb && (*b++ = *p++) != EOS)

    ;

  *b = EOS;

  return patbuf;

}

static int

g_strncmp(const Char *s1, const char *s2, size_t n)

{

  int rv = 0;

  while (n--) {

    rv = *(Char *)s1 - *(const unsigned char *)s2++;

    if (rv)

      break;

    if (*s1++ == '\0')

      break;

  }

  return rv;

}

static int

g_charclass(const Char **patternp, Char **bufnextp)

{

  const Char *pattern = *patternp + 1;

  Char *bufnext = *bufnextp;

  const Char *colon;

  struct cclass *cc;

  size_t len;

  if ((colon = g_strchr(pattern, ':')) == NULL || colon[1] != ']')

    return 1;  /* not a character class */

  len = (size_t)(colon - pattern);

  for (cc = cclasses; cc->name != NULL; cc++) {

    if (!g_strncmp(pattern, cc->name, len) && cc->name[len] == '\0')

      break;

  }

  if (cc->name == NULL)

    return -1;  /* invalid character class */

  *bufnext++ = M_CLASS;

  *bufnext++ = (Char)(cc - &cclasses[0]);

  *bufnextp = bufnext;

  *patternp += len + 3;

  return 0;

}

/*

 * 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.  It is not an error

 * to find no matches.

 */

static int

glob0(const Char *pattern, glob_t *pglob, struct glob_lim *limitp)

{

  const Char *qpatnext;

  int c, err;

  size_t oldpathc;

  Char *bufnext, patbuf[PATH_MAX];

  qpatnext = globtilde(pattern, patbuf, PATH_MAX, pglob);

  oldpathc = pglob->gl_pathc;

  bufnext = patbuf;

  /* We don't need to check for buffer overflow any more. */

  while ((c = *qpatnext++) != EOS) {

    switch (c) {

    case LBRACKET:

      c = *qpatnext;

      if (c == NOT)

        ++qpatnext;

      if (*qpatnext == EOS ||

          g_strchr(qpatnext+1, RBRACKET) == NULL) {

        *bufnext++ = LBRACKET;

        if (c == NOT)

          --qpatnext;

        break;

      }

      *bufnext++ = M_SET;

      if (c == NOT)

        *bufnext++ = M_NOT;

      c = *qpatnext++;

      do {

        if (c == LBRACKET && *qpatnext == ':') {

          do {

            err = g_charclass(&qpatnext,

                &bufnext);

            if (err)

              break;

            c = *qpatnext++;

          } while (c == LBRACKET && *qpatnext == ':');

          if (err == -1 &&

              !(pglob->gl_flags & GLOB_NOCHECK))

            return GLOB_NOMATCH;

          if (c == RBRACKET)

            break;

        }

        *bufnext++ = CHAR(c);

        if (*qpatnext == RANGE &&

            (c = qpatnext[1]) != RBRACKET) {

          *bufnext++ = M_RNG;

          *bufnext++ = CHAR(c);

          qpatnext += 2;

        }

      } while ((c = *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, patbuf+PATH_MAX-1, pglob, limitp)) != 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, limitp, NULL));

    else

      return(GLOB_NOMATCH);

  }

  if (!(pglob->gl_flags & GLOB_NOSORT)) {

    if ((pglob->gl_flags & GLOB_KEEPSTAT)) {

      /* Keep the paths and stat info synced during sort */

      struct glob_path_stat *path_stat;

      size_t i;

      size_t n = pglob->gl_pathc - oldpathc;

      size_t o = pglob->gl_offs + oldpathc;

      if ((path_stat = calloc(n, sizeof(*path_stat))) == NULL)

        return GLOB_NOSPACE;

      for (i = 0; i < n; i++) {

        path_stat[i].gps_path = pglob->gl_pathv[o + i];

        path_stat[i].gps_stat = pglob->gl_statv[o + i];

      }

      qsort(path_stat, n, sizeof(*path_stat), compare_gps);

      for (i = 0; i < n; i++) {

        pglob->gl_pathv[o + i] = path_stat[i].gps_path;

        pglob->gl_statv[o + i] = path_stat[i].gps_stat;

      }

      free(path_stat);

    } else {

      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

compare_gps(const void *_p, const void *_q)

{

  const struct glob_path_stat *p = (const struct glob_path_stat *)_p;

  const struct glob_path_stat *q = (const struct glob_path_stat *)_q;

  return(strcmp(p->gps_path, q->gps_path));

}

static int

glob1(Char *pattern, Char *pattern_last, glob_t *pglob, struct glob_lim *limitp)

{

  Char pathbuf[PATH_MAX];

  /* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */

  if (*pattern == EOS)

    return(0);

  return(glob2(pathbuf, pathbuf+PATH_MAX-1,

      pathbuf, pathbuf+PATH_MAX-1,

      pattern, pattern_last, pglob, limitp));

}

/*

 * 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 *pathbuf_last, Char *pathend, Char *pathend_last,

    Char *pattern, Char *pattern_last, glob_t *pglob, struct glob_lim *limitp)

{

  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 ((pglob->gl_flags & GLOB_LIMIT) &&

          limitp->glim_stat++ >= GLOB_LIMIT_STAT) {

        errno = 0;

        *pathend++ = SEP;

        *pathend = EOS;

        return(GLOB_NOSPACE);

      }

      if (g_lstat(pathbuf, &sb, pglob))

        return(0);

      if (((pglob->gl_flags & GLOB_MARK) &&

          pathend[-1] != SEP) && (S_ISDIR(sb.st_mode) ||

          (S_ISLNK(sb.st_mode) &&

          (g_stat(pathbuf, &sb, pglob) == 0) &&

          S_ISDIR(sb.st_mode)))) {

        if (pathend+1 > pathend_last)

          return (1);

        *pathend++ = SEP;

        *pathend = EOS;

      }

      ++pglob->gl_matchc;

      return(globextend(pathbuf, pglob, limitp, &sb));

    }

    /* 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 (1);

      *q++ = *p++;

    }

    if (!anymeta) {   /* No expansion, do next segment. */

      pathend = q;

      pattern = p;

      while (*pattern == SEP) {

        if (pathend+1 > pathend_last)

          return (1);

        *pathend++ = *pattern++;

      }

    } else

      /* Need expansion, recurse. */

      return(glob3(pathbuf, pathbuf_last, pathend,

          pathend_last, pattern, p, pattern_last,

          pglob, limitp));

  }

  /* NOTREACHED */

}

static int

glob3(Char *pathbuf, Char *pathbuf_last, Char *pathend, Char *pathend_last,

    Char *pattern, Char *restpattern, Char *restpattern_last, glob_t *pglob,

    struct glob_lim *limitp)

{

  struct dirent *dp;

  DIR *dirp;

  int err;

  char buf[PATH_MAX];

  /*

   * 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.

   */

  struct dirent *(*readdirfunc)(void *);

  if (pathend > pathend_last)

    return (1);

  *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 = (struct dirent *(*)(void *))readdir;

  while ((dp = (*readdirfunc)(dirp))) {

    u_char *sc;

    Char *dc;

    if ((pglob->gl_flags & GLOB_LIMIT) &&

        limitp->glim_readdir++ >= GLOB_LIMIT_READDIR) {

      errno = 0;

      *pathend++ = SEP;

      *pathend = EOS;

      err = GLOB_NOSPACE;

      break;

    }

    /* Initial DOT must be matched literally. */

    if (dp->d_name[0] == DOT && *pattern != DOT)

      continue;

    dc = pathend;

    sc = (u_char *) dp->d_name;

    while (dc < pathend_last && (*dc++ = *sc++) != EOS)

      ;

    if (dc >= pathend_last) {

      *dc = EOS;

      err = 1;

      break;

    }

    if (!match(pathend, pattern, restpattern)) {

      *pathend = EOS;

      continue;

    }

    err = glob2(pathbuf, pathbuf_last, --dc, pathend_last,

        restpattern, restpattern_last, pglob, limitp);

    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 accommodate 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, struct glob_lim *limitp,

    struct stat *sb)

{

  char **pathv;

  size_t i, newn, len;

  char *copy = NULL;

  const Char *p;

  struct stat **statv;

  newn = 2 + pglob->gl_pathc + pglob->gl_offs;

  if (pglob->gl_offs >= SSIZE_MAX ||

      pglob->gl_pathc >= SSIZE_MAX ||

      newn >= SSIZE_MAX ||

      SIZE_MAX / sizeof(*pathv) <= newn ||

      SIZE_MAX / sizeof(*statv) <= newn) {

 nospace:

    for (i = pglob->gl_offs; i < newn - 2; i++) {

      if (pglob->gl_pathv && pglob->gl_pathv[i])

        free(pglob->gl_pathv[i]);

      if ((pglob->gl_flags & GLOB_KEEPSTAT) != 0 &&

          pglob->gl_pathv && pglob->gl_pathv[i])

        free(pglob->gl_statv[i]);

    }

    free(pglob->gl_pathv);

    pglob->gl_pathv = NULL;

    free(pglob->gl_statv);

    pglob->gl_statv = NULL;

    return(GLOB_NOSPACE);

  }

  pathv = reallocarray(pglob->gl_pathv, newn, sizeof(*pathv));

  if (pathv == NULL)

    goto 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; i--)

      *--pathv = NULL;

  }

  pglob->gl_pathv = pathv;

  if ((pglob->gl_flags & GLOB_KEEPSTAT) != 0) {

    statv = reallocarray(pglob->gl_statv, newn, sizeof(*statv));

    if (statv == NULL)

      goto nospace;

    if (pglob->gl_statv == NULL && pglob->gl_offs > 0) {

      /* first time around -- clear initial gl_offs items */

      statv += pglob->gl_offs;

      for (i = pglob->gl_offs; i > 0; i--)

        *--statv = NULL;

    }

    pglob->gl_statv = statv;

    if (sb == NULL)

      statv[pglob->gl_offs + pglob->gl_pathc] = NULL;

    else {

      limitp->glim_malloc += sizeof(**statv);

      if ((pglob->gl_flags & GLOB_LIMIT) &&

          limitp->glim_malloc >= GLOB_LIMIT_MALLOC) {

        errno = 0;

        return(GLOB_NOSPACE);

      }

      if ((statv[pglob->gl_offs + pglob->gl_pathc] =

          malloc(sizeof(**statv))) == NULL)

        goto copy_error;

      memcpy(statv[pglob->gl_offs + pglob->gl_pathc], sb,

          sizeof(*sb));

    }

    statv[pglob->gl_offs + pglob->gl_pathc + 1] = NULL;

  }

  for (p = path; *p++;)

    ;

  len = (size_t)(p - path);

  limitp->glim_malloc += len;

  if ((copy = malloc(len)) != NULL) {

    if (g_Ctoc(path, copy, len)) {

      free(copy);

      return(GLOB_NOSPACE);

    }

    pathv[pglob->gl_offs + pglob->gl_pathc++] = copy;

  }

  pathv[pglob->gl_offs + pglob->gl_pathc] = NULL;

  if ((pglob->gl_flags & GLOB_LIMIT) &&

      (newn * sizeof(*pathv)) + limitp->glim_malloc >

      GLOB_LIMIT_MALLOC) {

    errno = 0;

    return(GLOB_NOSPACE);

  }

 copy_error:

  return(copy == NULL ? GLOB_NOSPACE : 0);

}

/*

 * pattern matching function for filenames.  Each occurrence of the *

 * pattern causes an iteration.

 *

 * Note, this function differs from the original as per the discussion

 * here: https://research.swtch.com/glob

 *

 * Basically we removed the recursion and made it use the algorithm

 * from Russ Cox to not go quadratic on cases like a file called

 * ("a" x 100) . "x" matched against a pattern like "a*a*a*a*a*a*a*y".

 */

static int

match(Char *name, Char *pat, Char *patend)

{

  int ok, negate_range;

  Char c, k;

  Char *nextp = NULL;

  Char *nextn = NULL;

loop:

  while (pat < patend) {

    c = *pat++;

    switch (c & M_MASK) {

    case M_ALL:

      while (pat < patend && (*pat & M_MASK) == M_ALL)

        pat++; /* eat consecutive '*' */

      if (pat == patend)

        return(1);

      if (*name == EOS)

        return(0);

      nextn = name + 1;

      nextp = pat - 1;

      break;

    case M_ONE:

      if (*name++ == EOS)

        goto fail;

      break;

    case M_SET:

      ok = 0;

      if ((k = *name++) == EOS)

        goto fail;

      if ((negate_range = ((*pat & M_MASK) == M_NOT)) != EOS)

        ++pat;

      while (((c = *pat++) & M_MASK) != M_END) {

        if ((c & M_MASK) == M_CLASS) {

          Char idx = *pat & M_MASK;

          if (idx < NCCLASSES &&

              cclasses[idx].isctype(k))

            ok = 1;

          ++pat;

        }

        if ((*pat & M_MASK) == M_RNG) {

          if (c <= k && k <= pat[1])

            ok = 1;

          pat += 2;

        } else if (c == k)

          ok = 1;