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

1 files changed, 435 insertions, 232 deletions

diff --git a/lib/libc/gen/fnmatch.c b/lib/libc/gen/fnmatch.c
index a005013aab6..c3d1a3ccf5e 100644
--- a/lib/libc/gen/fnmatch.c
+++ b/lib/libc/gen/fnmatch.c
@@ -1,249 +1,101 @@
-/*	$OpenBSD: fnmatch.c,v 1.15 2011/02/10 21:31:59 stsp 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	EOS	'\0'
-
 #define	RANGE_MATCH	1
 #define	RANGE_NOMATCH	0
 #define	RANGE_ERROR	(-1)
 
-/* Limit of recursion during matching attempts. */
-#define __FNM_MAX_RECUR	64
-
-static int rangematch(const char *, char, int, char **);
-static int classmatch(const char *, char, int, const char **);
-static int __fnmatch(const char *, const char *, int, int);
-
-int
-fnmatch(const char *pattern, const char *string, int flags)
-{
-	int e;
-
-	if (strnlen(pattern, PATH_MAX) == PATH_MAX ||
-	    strnlen(string, PATH_MAX) == PATH_MAX)
-		return (FNM_NOMATCH);
-		
-	e = __fnmatch(pattern, string, flags, __FNM_MAX_RECUR);
-	if (e == -1)
-		e = FNM_NOMATCH;
-	return (e);
-}
-
-static int
-__fnmatch(const char *pattern, const char *string, int flags, int recur)
-{
-	const char *stringstart;
-	char *newp;
-	char c, test;
-	int e;
-
-	if (recur-- == 0)
-		return (-1);
-
-	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) {
-				e = __fnmatch(pattern, string,
-				    flags & ~FNM_PERIOD, recur);
-				if (e != FNM_NOMATCH)
-					return (e);
-				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 */
-}
-
-static int
-rangematch(const char *pattern, char test, int flags, char **newp)
-{
-	int negate, ok, rv;
-	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)
-	 */
-	if ((negate = (*pattern == '!' || *pattern == '^')))
-		++pattern;
-
-	if (flags & FNM_CASEFOLD)
-		test = (char)tolower((unsigned char)test);
-
-	/*
-	 * 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
-	 */
-	ok = 0;
-	c = *pattern++;
-	do {
-		if (c == '[' && *pattern == ':') {
-			do {
-				rv = classmatch(pattern + 1, test,
-				    (flags & FNM_CASEFOLD), &pattern);
-				if (rv == RANGE_MATCH)
-					ok = 1;
-				c = *pattern++;
-			} while (rv != RANGE_ERROR && c == '[' && *pattern == ':');
-			if (c == ']')
-				break;
-		}
-		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);
-}
-
 static int
 classmatch(const char *pattern, char test, int foldcase, const char **ep)
 {
@@ -251,9 +103,17 @@ classmatch(const char *pattern, char test, int foldcase, const char **ep)
 	const char *colon;
 	size_t len;
 	int rval = RANGE_NOMATCH;
+	const char * const mismatch = pattern;
+
+	if (*pattern != '[' || pattern[1] != ':') {
+		*ep = mismatch;
+		return(RANGE_ERROR);
+	}
+
+	pattern += 2;
 
 	if ((colon = strchr(pattern, ':')) == NULL || colon[1] != ']') {
-		*ep = pattern - 2;
+		*ep = mismatch;
 		return(RANGE_ERROR);
 	}
 	*ep = colon + 2;
@@ -269,9 +129,352 @@ classmatch(const char *pattern, char test, int foldcase, const char **ep)
 		}
 	}
 	if (cc->name == NULL) {
-		/* invalid character class, return EOS */
-		*ep = colon + strlen(colon);
+		/* 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 * 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;
+}
+
+
+int fnmatch(const char *pattern, const char *string, int flags)
+{
+    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 ((flags & FNM_PERIOD) && (*string == '.'))
+        {
+            if (*pattern == '.')
+                ++pattern;
+            else if (escape && (*pattern == '\\') && (pattern[1] == '.'))
+                pattern += 2;
+            else
+                return FNM_NOMATCH;
+            ++string;
+        }
+
+        /* 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');
+        }
+
+        /* Allow pattern '*' to be consumed even with no remaining string to 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;
+}