fnmatch.c: Update to version in OpenBSD HEAD

Upgrade fnmatch.c from OpenBSD version 1.13 to 1.16.
This is needed primarily to address CVE-2011-0419.

This is a straight copy from upstream's version at
http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/gen/fnmatch.c and
incorporates the following changes:

Revision 1.16:
New fnmatch(3) implementation which is not recursive.
Written and provided under BSD licence by William A. Rowe Jr.
Originally released in Apache APR-1.4.5.
Merged class matching code from r1.14 and PATH_MAX check from r1.15.
ok miod millert

Revision 1.15:
Put a limit on recursion during matching, and reject input of size greater
or equal PATH_MAX. Based on similar fix made in NetBSD.
ok miod@ millert@

Revision 1.14:
POSIX character class support for fnmatch(3) and glob(3).  OK deraadt@

Version 1.14 introduced charclasses.h, which we copy unmodified
from upstream version 1.1.
http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/gen/charclass.h

Bug: 3435120
Change-Id: I45133468f0c3d439fd10eb087a1c647799f9d25b

2 files changed, 486 insertions, 182 deletions

diff --git a/libc/unistd/charclass.h b/libc/unistd/charclass.h
new file mode 100644
index 0000000..5edb2c1
--- /dev/null
+++ b/libc/unistd/charclass.h
@@ -0,0 +1,29 @@
+/*
+ * Public domain, 2008, Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * $OpenBSD: charclass.h,v 1.1 2008/10/01 23:04:13 millert Exp $
+ */
+
+/*
+ * POSIX character class support for fnmatch() and glob().
+ */
+static struct cclass {
+	const char *name;
+	int (*isctype)(int);
+} cclasses[] = {
+	{ "alnum",	isalnum },
+	{ "alpha",	isalpha },
+	{ "blank",	isblank },
+	{ "cntrl",	iscntrl },
+	{ "digit",	isdigit },
+	{ "graph",	isgraph },
+	{ "lower",	islower },
+	{ "print",	isprint },
+	{ "punct",	ispunct },
+	{ "space",	isspace },
+	{ "upper",	isupper },
+	{ "xdigit",	isxdigit },
+	{ NULL,		NULL }
+};
+
+#define NCCLASSES	(sizeof(cclasses) / sizeof(cclasses[0]) - 1)
diff --git a/libc/unistd/fnmatch.c b/libc/unistd/fnmatch.c
index ad31c9e..c3d1a3c 100644
--- a/libc/unistd/fnmatch.c
+++ b/libc/unistd/fnmatch.c
@@ -1,205 +1,480 @@
-/*      $OpenBSD: fnmatch.c,v 1.13 2006/03/31 05:34:14 deraadt Exp $        */
+/*	$OpenBSD: fnmatch.c,v 1.16 2011/12/06 11:47:46 stsp Exp $	*/
 
-/*
- * Copyright (c) 1989, 1993, 1994
- *      The Regents of the University of California.  All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Guido van Rossum.
- *
+/* Copyright (c) 2011, VMware, Inc.
+ * All rights reserved.
+ * 
  * 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
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * 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.
+ *     * Neither the name of the VMware, Inc. 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 COPYRIGHT HOLDERS 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.
+ * ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. 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.
  */
 
 /*
- * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
- * Compares a filename or pathname to a pattern.
+ * Copyright (c) 2008 Todd C. Miller <millert@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* Authored by William A. Rowe Jr. <wrowe; apache.org, vmware.com>, April 2011
+ *
+ * Derived from The Open Group Base Specifications Issue 7, IEEE Std 1003.1-2008
+ * as described in;
+ *   http://pubs.opengroup.org/onlinepubs/9699919799/functions/fnmatch.html
+ *
+ * Filename pattern matches defined in section 2.13, "Pattern Matching Notation"
+ * from chapter 2. "Shell Command Language"
+ *   http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_13
+ * where; 1. A bracket expression starting with an unquoted <circumflex> '^' 
+ * character CONTINUES to specify a non-matching list; 2. an explicit <period> '.' 
+ * in a bracket expression matching list, e.g. "[.abc]" does NOT match a leading 
+ * <period> in a filename; 3. a <left-square-bracket> '[' which does not introduce
+ * a valid bracket expression is treated as an ordinary character; 4. a differing
+ * number of consecutive slashes within pattern and string will NOT match;
+ * 5. a trailing '\' in FNM_ESCAPE mode is treated as an ordinary '\' character.
+ *
+ * Bracket expansion defined in section 9.3.5, "RE Bracket Expression",
+ * from chapter 9, "Regular Expressions"
+ *   http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_03_05
+ * with no support for collating symbols, equivalence class expressions or 
+ * character class expressions.  A partial range expression with a leading 
+ * hyphen following a valid range expression will match only the ordinary
+ * <hyphen> and the ending character (e.g. "[a-m-z]" will match characters 
+ * 'a' through 'm', a <hyphen> '-', or a 'z').
+ *
+ * Supports BSD extensions FNM_LEADING_DIR to match pattern to the end of one
+ * path segment of string, and FNM_CASEFOLD to ignore alpha case.
+ *
+ * NOTE: Only POSIX/C single byte locales are correctly supported at this time.
+ * Notably, non-POSIX locales with FNM_CASEFOLD produce undefined results,
+ * particularly in ranges of mixed case (e.g. "[A-z]") or spanning alpha and
+ * nonalpha characters within a range.
+ *
+ * XXX comments below indicate porting required for multi-byte character sets
+ * and non-POSIX locale collation orders; requires mbr* APIs to track shift
+ * state of pattern and string (rewinding pattern and string repeatedly).
+ *
+ * Certain parts of the code assume 0x00-0x3F are unique with any MBCS (e.g.
+ * UTF-8, SHIFT-JIS, etc).  Any implementation allowing '\' as an alternate
+ * path delimiter must be aware that 0x5C is NOT unique within SHIFT-JIS.
  */
 
-#include <ctype.h>
-#include <stdio.h>
-#include <string.h>
 #include <fnmatch.h>
+#include <string.h>
+#include <ctype.h>
+#include <limits.h>
+
+#include "charclass.h"
+
+#define	RANGE_MATCH	1
+#define	RANGE_NOMATCH	0
+#define	RANGE_ERROR	(-1)
 
-#define EOS        '\0'
+static int
+classmatch(const char *pattern, char test, int foldcase, const char **ep)
+{
+	struct cclass *cc;
+	const char *colon;
+	size_t len;
+	int rval = RANGE_NOMATCH;
+	const char * const mismatch = pattern;
+
+	if (*pattern != '[' || pattern[1] != ':') {
+		*ep = mismatch;
+		return(RANGE_ERROR);
+	}
 
-#define RANGE_MATCH        1
-#define RANGE_NOMATCH        0
-#define RANGE_ERROR        (-1)
+	pattern += 2;
 
-static int rangematch(const char *, char, int, char **);
+	if ((colon = strchr(pattern, ':')) == NULL || colon[1] != ']') {
+		*ep = mismatch;
+		return(RANGE_ERROR);
+	}
+	*ep = colon + 2;
+	len = (size_t)(colon - pattern);
 
-int
-fnmatch(const char *pattern, const char *string, int flags)
+	if (foldcase && strncmp(pattern, "upper:]", 7) == 0)
+		pattern = "lower:]";
+	for (cc = cclasses; cc->name != NULL; cc++) {
+		if (!strncmp(pattern, cc->name, len) && cc->name[len] == '\0') {
+			if (cc->isctype((unsigned char)test))
+				rval = RANGE_MATCH;
+			break;
+		}
+	}
+	if (cc->name == NULL) {
+		/* invalid character class, treat as normal text */
+		*ep = mismatch;
+		rval = RANGE_ERROR;
+	}
+	return(rval);
+}
+
+/* Most MBCS/collation/case issues handled here.  Wildcard '*' is not handled.
+ * EOS '\0' and the FNM_PATHNAME '/' delimiters are not advanced over, 
+ * however the "\/" sequence is advanced to '/'.
+ *
+ * Both pattern and string are **char to support pointer increment of arbitrary
+ * multibyte characters for the given locale, in a later iteration of this code
+ */
+static int fnmatch_ch(const char **pattern, const char **string, int flags)
 {
-        const char *stringstart;
-        char *newp;
-        char c, test;
-
-        for (stringstart = string;;)
-                switch (c = *pattern++) {
-                case EOS:
-                        if ((flags & FNM_LEADING_DIR) && *string == '/')
-                                return (0);
-                        return (*string == EOS ? 0 : FNM_NOMATCH);
-                case '?':
-                        if (*string == EOS)
-                                return (FNM_NOMATCH);
-                        if (*string == '/' && (flags & FNM_PATHNAME))
-                                return (FNM_NOMATCH);
-                        if (*string == '.' && (flags & FNM_PERIOD) &&
-                            (string == stringstart ||
-                            ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
-                                return (FNM_NOMATCH);
-                        ++string;
-                        break;
-                case '*':
-                        c = *pattern;
-                        /* Collapse multiple stars. */
-                        while (c == '*')
-                                c = *++pattern;
-
-                        if (*string == '.' && (flags & FNM_PERIOD) &&
-                            (string == stringstart ||
-                            ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
-                                return (FNM_NOMATCH);
-
-                        /* Optimize for pattern with * at end or before /. */
-                        if (c == EOS) {
-                                if (flags & FNM_PATHNAME)
-                                        return ((flags & FNM_LEADING_DIR) ||
-                                            strchr(string, '/') == NULL ?
-                                            0 : FNM_NOMATCH);
-                                else
-                                        return (0);
-                        } else if (c == '/' && (flags & FNM_PATHNAME)) {
-                                if ((string = strchr(string, '/')) == NULL)
-                                        return (FNM_NOMATCH);
-                                break;
-                        }
-
-                        /* General case, use recursion. */
-                        while ((test = *string) != EOS) {
-                                if (!fnmatch(pattern, string, flags & ~FNM_PERIOD))
-                                        return (0);
-                                if (test == '/' && (flags & FNM_PATHNAME))
-                                        break;
-                                ++string;
-                        }
-                        return (FNM_NOMATCH);
-                case '[':
-                        if (*string == EOS)
-                                return (FNM_NOMATCH);
-                        if (*string == '/' && (flags & FNM_PATHNAME))
-                                return (FNM_NOMATCH);
-                        if (*string == '.' && (flags & FNM_PERIOD) &&
-                            (string == stringstart ||
-                            ((flags & FNM_PATHNAME) && *(string - 1) == '/')))
-                                return (FNM_NOMATCH);
-
-                        switch (rangematch(pattern, *string, flags, &newp)) {
-                        case RANGE_ERROR:
-                                /* not a good range, treat as normal text */
-                                goto normal;
-                        case RANGE_MATCH:
-                                pattern = newp;
-                                break;
-                        case RANGE_NOMATCH:
-                                return (FNM_NOMATCH);
-                        }
-                        ++string;
-                        break;
-                case '\\':
-                        if (!(flags & FNM_NOESCAPE)) {
-                                if ((c = *pattern++) == EOS) {
-                                        c = '\\';
-                                        --pattern;
-                                }
-                        }
-                        /* FALLTHROUGH */
-                default:
-                normal:
-                        if (c != *string && !((flags & FNM_CASEFOLD) &&
-                                 (tolower((unsigned char)c) ==
-                                 tolower((unsigned char)*string))))
-                                return (FNM_NOMATCH);
-                        ++string;
-                        break;
-                }
-        /* NOTREACHED */
+    const char * const mismatch = *pattern;
+    const int nocase = !!(flags & FNM_CASEFOLD);
+    const int escape = !(flags & FNM_NOESCAPE);
+    const int slash = !!(flags & FNM_PATHNAME);
+    int result = FNM_NOMATCH;
+    const char *startch;
+    int negate;
+
+    if (**pattern == '[')
+    {
+        ++*pattern;
+
+        /* Handle negation, either leading ! or ^ operators (never both) */
+        negate = ((**pattern == '!') || (**pattern == '^'));
+        if (negate)
+            ++*pattern;
+
+        /* ']' is an ordinary character at the start of the range pattern */
+        if (**pattern == ']')
+            goto leadingclosebrace;
+
+        while (**pattern)
+        {
+            if (**pattern == ']') {
+                ++*pattern;
+                /* XXX: Fix for MBCS character width */
+                ++*string;
+                return (result ^ negate);
+            }
+
+            if (escape && (**pattern == '\\')) {
+                ++*pattern;
+
+                /* Patterns must be terminated with ']', not EOS */
+                if (!**pattern)
+                    break;
+            }
+
+            /* Patterns must be terminated with ']' not '/' */
+            if (slash && (**pattern == '/'))
+                break;
+
+            /* Match character classes. */
+            if (classmatch(*pattern, **string, nocase, pattern)
+                == RANGE_MATCH) {
+                result = 0;
+                continue;
+            }
+
+leadingclosebrace:
+            /* Look at only well-formed range patterns; 
+             * "x-]" is not allowed unless escaped ("x-\]")
+             * XXX: Fix for locale/MBCS character width
+             */
+            if (((*pattern)[1] == '-') && ((*pattern)[2] != ']'))
+            {
+                startch = *pattern;
+                *pattern += (escape && ((*pattern)[2] == '\\')) ? 3 : 2;
+
+                /* NOT a properly balanced [expr] pattern, EOS terminated 
+                 * or ranges containing a slash in FNM_PATHNAME mode pattern
+                 * fall out to to the rewind and test '[' literal code path
+                 */
+                if (!**pattern || (slash && (**pattern == '/')))
+                    break;
+
+                /* XXX: handle locale/MBCS comparison, advance by MBCS char width */
+                if ((**string >= *startch) && (**string <= **pattern))
+                    result = 0;
+                else if (nocase && (isupper(**string) || isupper(*startch)
+                                                      || isupper(**pattern))
+                            && (tolower(**string) >= tolower(*startch)) 
+                            && (tolower(**string) <= tolower(**pattern)))
+                    result = 0;
+
+                ++*pattern;
+                continue;
+            }
+
+            /* XXX: handle locale/MBCS comparison, advance by MBCS char width */
+            if ((**string == **pattern))
+                result = 0;
+            else if (nocase && (isupper(**string) || isupper(**pattern))
+                            && (tolower(**string) == tolower(**pattern)))
+                result = 0;
+
+            ++*pattern;
+        }
+
+        /* NOT a properly balanced [expr] pattern; Rewind
+         * and reset result to test '[' literal
+         */
+        *pattern = mismatch;
+        result = FNM_NOMATCH;
+    }
+    else if (**pattern == '?') {
+        /* Optimize '?' match before unescaping **pattern */
+        if (!**string || (slash && (**string == '/')))
+            return FNM_NOMATCH;
+        result = 0;
+        goto fnmatch_ch_success;
+    }
+    else if (escape && (**pattern == '\\') && (*pattern)[1]) {
+        ++*pattern;
+    }
+
+    /* XXX: handle locale/MBCS comparison, advance by the MBCS char width */
+    if (**string == **pattern)
+        result = 0;
+    else if (nocase && (isupper(**string) || isupper(**pattern))
+                    && (tolower(**string) == tolower(**pattern)))
+        result = 0;
+
+    /* Refuse to advance over trailing slash or nulls
+     */
+    if (!**string || !**pattern || (slash && ((**string == '/') || (**pattern == '/'))))
+        return result;
+
+fnmatch_ch_success:
+    ++*pattern;
+    ++*string;
+    return result;
 }
 
-static int
-rangematch(const char *pattern, char test, int flags, char **newp)
+
+int fnmatch(const char *pattern, const char *string, int flags)
 {
-        int negate, ok;
-        char c, c2;
-
-        /*
-         * A bracket expression starting with an unquoted circumflex
-         * character produces unspecified results (IEEE 1003.2-1992,
-         * 3.13.2).  This implementation treats it like '!', for
-         * consistency with the regular expression syntax.
-         * J.T. Conklin (conklin@ngai.kaleida.com)
+    static const char dummystring[2] = {' ', 0};
+    const int escape = !(flags & FNM_NOESCAPE);
+    const int slash = !!(flags & FNM_PATHNAME);
+    const int leading_dir = !!(flags & FNM_LEADING_DIR);
+    const char *strendseg;
+    const char *dummyptr;
+    const char *matchptr;
+    int wild;
+    /* For '*' wild processing only; surpress 'used before initialization'
+     * warnings with dummy initialization values;
+     */
+    const char *strstartseg = NULL;
+    const char *mismatch = NULL;
+    int matchlen = 0;
+
+    if (strnlen(pattern, PATH_MAX) == PATH_MAX ||
+        strnlen(string, PATH_MAX) == PATH_MAX)
+            return (FNM_NOMATCH);
+
+    if (*pattern == '*')
+        goto firstsegment;
+
+    while (*pattern && *string)
+    {
+        /* Pre-decode "\/" which has no special significance, and
+         * match balanced slashes, starting a new segment pattern
+         */
+        if (slash && escape && (*pattern == '\\') && (pattern[1] == '/'))
+            ++pattern;
+        if (slash && (*pattern == '/') && (*string == '/')) {
+            ++pattern;
+            ++string;
+        }            
+
+firstsegment:
+        /* At the beginning of each segment, validate leading period behavior.
          */
-        if ((negate = (*pattern == '!' || *pattern == '^')))
+        if ((flags & FNM_PERIOD) && (*string == '.'))
+        {
+            if (*pattern == '.')
                 ++pattern;
+            else if (escape && (*pattern == '\\') && (pattern[1] == '.'))
+                pattern += 2;
+            else
+                return FNM_NOMATCH;
+            ++string;
+        }
 
-        if (flags & FNM_CASEFOLD)
-                test = (char)tolower((unsigned char)test);
+        /* Determine the end of string segment
+         *
+         * Presumes '/' character is unique, not composite in any MBCS encoding
+         */
+        if (slash) {
+            strendseg = strchr(string, '/');
+            if (!strendseg)
+                strendseg = strchr(string, '\0');
+        }
+        else {
+            strendseg = strchr(string, '\0');
+        }
 
-        /*
-         * A right bracket shall lose its special meaning and represent
-         * itself in a bracket expression if it occurs first in the list.
-         * -- POSIX.2 2.8.3.2
+        /* Allow pattern '*' to be consumed even with no remaining string to match
          */
-        ok = 0;
-        c = *pattern++;
-        do {
-                if (c == '\\' && !(flags & FNM_NOESCAPE))
-                        c = *pattern++;
-                if (c == EOS)
-                        return (RANGE_ERROR);
-                if (c == '/' && (flags & FNM_PATHNAME))
-                        return (RANGE_NOMATCH);
-                if ((flags & FNM_CASEFOLD))
-                        c = (char)tolower((unsigned char)c);
-                if (*pattern == '-'
-                    && (c2 = *(pattern+1)) != EOS && c2 != ']') {
-                        pattern += 2;
-                        if (c2 == '\\' && !(flags & FNM_NOESCAPE))
-                                c2 = *pattern++;
-                        if (c2 == EOS)
-                                return (RANGE_ERROR);
-                        if (flags & FNM_CASEFOLD)
-                                c2 = (char)tolower((unsigned char)c2);
-                        if (c <= test && test <= c2)
-                                ok = 1;
-                } else if (c == test)
-                        ok = 1;
-        } while ((c = *pattern++) != ']');
-
-        *newp = (char *)pattern;
-        return (ok == negate ? RANGE_NOMATCH : RANGE_MATCH);
+        while (*pattern)
+        {
+            if ((string > strendseg)
+                || ((string == strendseg) && (*pattern != '*')))
+                break;
+
+            if (slash && ((*pattern == '/')
+                           || (escape && (*pattern == '\\')
+                                      && (pattern[1] == '/'))))
+                break;
+
+            /* Reduce groups of '*' and '?' to n '?' matches
+             * followed by one '*' test for simplicity
+             */
+            for (wild = 0; ((*pattern == '*') || (*pattern == '?')); ++pattern)
+            {
+                if (*pattern == '*') {
+                    wild = 1;
+                }
+                else if (string < strendseg) {  /* && (*pattern == '?') */
+                    /* XXX: Advance 1 char for MBCS locale */
+                    ++string;
+                }
+                else {  /* (string >= strendseg) && (*pattern == '?') */
+                    return FNM_NOMATCH;
+                }
+            }
+
+            if (wild)
+            {
+                strstartseg = string;
+                mismatch = pattern;
+
+                /* Count fixed (non '*') char matches remaining in pattern
+                 * excluding '/' (or "\/") and '*'
+                 */
+                for (matchptr = pattern, matchlen = 0; 1; ++matchlen)
+                {
+                    if ((*matchptr == '\0') 
+                        || (slash && ((*matchptr == '/')
+                                      || (escape && (*matchptr == '\\')
+                                                 && (matchptr[1] == '/')))))
+                    {
+                        /* Compare precisely this many trailing string chars,
+                         * the resulting match needs no wildcard loop
+                         */
+                        /* XXX: Adjust for MBCS */
+                        if (string + matchlen > strendseg)
+                            return FNM_NOMATCH;
+
+                        string = strendseg - matchlen;
+                        wild = 0;
+                        break;
+                    }
+
+                    if (*matchptr == '*')
+                    {
+                        /* Ensure at least this many trailing string chars remain
+                         * for the first comparison
+                         */
+                        /* XXX: Adjust for MBCS */
+                        if (string + matchlen > strendseg)
+                            return FNM_NOMATCH;
+
+                        /* Begin first wild comparison at the current position */
+                        break;
+                    }
+
+                    /* Skip forward in pattern by a single character match
+                     * Use a dummy fnmatch_ch() test to count one "[range]" escape
+                     */ 
+                    /* XXX: Adjust for MBCS */
+                    if (escape && (*matchptr == '\\') && matchptr[1]) {
+                        matchptr += 2;
+                    }
+                    else if (*matchptr == '[') {
+                        dummyptr = dummystring;
+                        fnmatch_ch(&matchptr, &dummyptr, flags);
+                    }
+                    else {
+                        ++matchptr;
+                    }
+                }
+            }
+
+            /* Incrementally match string against the pattern
+             */
+            while (*pattern && (string < strendseg))
+            {
+                /* Success; begin a new wild pattern search
+                 */
+                if (*pattern == '*')
+                    break;
+
+                if (slash && ((*string == '/')
+                              || (*pattern == '/')
+                              || (escape && (*pattern == '\\')
+                                         && (pattern[1] == '/'))))
+                    break;
+
+                /* Compare ch's (the pattern is advanced over "\/" to the '/',
+                 * but slashes will mismatch, and are not consumed)
+                 */
+                if (!fnmatch_ch(&pattern, &string, flags))
+                    continue;
+
+                /* Failed to match, loop against next char offset of string segment 
+                 * until not enough string chars remain to match the fixed pattern
+                 */
+                if (wild) {
+                    /* XXX: Advance 1 char for MBCS locale */
+                    string = ++strstartseg;
+                    if (string + matchlen > strendseg)
+                        return FNM_NOMATCH;
+
+                    pattern = mismatch;
+                    continue;
+                }
+                else
+                    return FNM_NOMATCH;
+            }
+        }
+
+        if (*string && !((slash || leading_dir) && (*string == '/')))
+            return FNM_NOMATCH;
+
+        if (*pattern && !(slash && ((*pattern == '/')
+                                    || (escape && (*pattern == '\\')
+                                               && (pattern[1] == '/')))))
+            return FNM_NOMATCH;
+
+        if (leading_dir && !*pattern && *string == '/')
+            return 0;
+    }
+
+    /* Where both pattern and string are at EOS, declare success
+     */
+    if (!*string && !*pattern)
+        return 0;
+
+    /* pattern didn't match to the end of string */
+    return FNM_NOMATCH;
 }