[PATCH 4/4] exclude/attr: share full pathname matching code

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

match_pathname's declaration in dir.h does not have any description to
discourage the use of this function elsewhere as this function is
highly tied to how excluded_from_list and path_matches work.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 attr.c | 35 +++------------------------
 dir.c  | 85 +++++++++++++++++++++++++++++++++++++++++-------------------------
 dir.h  |  3 +++
 3 files changed, 59 insertions(+), 64 deletions(-)

diff --git a/attr.c b/attr.c
index a28ce0d..2fc6353 100644
--- a/attr.c
+++ b/attr.c
@@ -659,8 +659,6 @@ static int path_matches(const char *pathname, int pathlen,
 {
 	const char *pattern = pat->pattern;
 	int prefix = pat->nowildcardlen;
-	const char *name;
-	int namelen;
 
 	if (pat->flags & EXC_FLAG_NODIR) {
 		return match_basename(basename,
@@ -668,36 +666,9 @@ static int path_matches(const char *pathname, int pathlen,
 				      pattern, prefix,
 				      pat->patternlen, pat->flags);
 	}
-	/*
-	 * match with FNM_PATHNAME; the pattern has base implicitly
-	 * in front of it.
-	 */
-	if (*pattern == '/') {
-		pattern++;
-		prefix--;
-	}
-
-	/*
-	 * note: unlike excluded_from_list, baselen here does not
-	 * count the trailing slash, and base[] does not end with
-	 * a trailing slash, either.
-	 */
-	if (pathlen < baselen + 1 ||
-	    (baselen && pathname[baselen] != '/') ||
-	    strncmp_icase(pathname, base, baselen))
-		return 0;
-
-	namelen = baselen ? pathlen - baselen - 1 : pathlen;
-	name = pathname + pathlen - namelen;
-
-	/*
-	 * if the non-wildcard part is longer than the remaining
-	 * pathname, surely it cannot match.
-	 */
-	if (!namelen || prefix > namelen)
-		return 0;
-
-	return fnmatch_icase(pattern, name, FNM_PATHNAME) == 0;
+	return match_pathname(pathname, pathlen,
+			      base, baselen,
+			      pattern, prefix, pat->patternlen, pat->flags);
 }
 
 static int macroexpand_one(int attr_nr, int rem);
diff --git a/dir.c b/dir.c
index 42c42cd..ee8e711 100644
--- a/dir.c
+++ b/dir.c
@@ -549,6 +549,53 @@ int match_basename(const char *basename, int basenamelen,
 	return 0;
 }
 
+int match_pathname(const char *pathname, int pathlen,
+		   const char *base, int baselen,
+		   const char *pattern, int prefix, int patternlen,
+		   int flags)
+{
+	const char *name;
+	int namelen;
+
+	/*
+	 * match with FNM_PATHNAME; the pattern has base implicitly
+	 * in front of it.
+	 */
+	if (*pattern == '/') {
+		pattern++;
+		prefix--;
+	}
+
+	/*
+	 * baselen does not count the trailing slash. base[] may or
+	 * may not end with a trailing slash though.
+	 */
+	if (pathlen < baselen + 1 ||
+	    (baselen && pathname[baselen] != '/') ||
+	    strncmp_icase(pathname, base, baselen))
+		return 0;
+
+	namelen = baselen ? pathlen - baselen - 1 : pathlen;
+	name = pathname + pathlen - namelen;
+
+	if (prefix) {
+		/*
+		 * if the non-wildcard part is longer than the
+		 * remaining pathname, surely it cannot match.
+		 */
+		if (prefix > namelen)
+			return 0;
+
+		if (strncmp_icase(pattern, name, prefix))
+			return 0;
+		pattern += prefix;
+		name    += prefix;
+		namelen -= prefix;
+	}
+
+	return fnmatch_icase(pattern, name, FNM_PATHNAME) == 0;
+}
+
 /* Scan the list and let the last match determine the fate.
  * Return 1 for exclude, 0 for include and -1 for undecided.
  */
@@ -563,9 +610,9 @@ int excluded_from_list(const char *pathname,
 
 	for (i = el->nr - 1; 0 <= i; i--) {
 		struct exclude *x = el->excludes[i];
-		const char *name, *exclude = x->pattern;
+		const char *exclude = x->pattern;
 		int to_exclude = x->flags & EXC_FLAG_NEGATIVE ? 0 : 1;
-		int namelen, prefix = x->nowildcardlen;
+		int prefix = x->nowildcardlen;
 
 		if (x->flags & EXC_FLAG_MUSTBEDIR) {
 			if (*dtype == DT_UNKNOWN)
@@ -583,36 +630,10 @@ int excluded_from_list(const char *pathname,
 			continue;
 		}
 
-		/* match with FNM_PATHNAME:
-		 * exclude has base (baselen long) implicitly in front of it.
-		 */
-		if (*exclude == '/') {
-			exclude++;
-			prefix--;
-		}
-
-		if (pathlen < x->baselen ||
-		    (x->baselen && pathname[x->baselen-1] != '/') ||
-		    strncmp_icase(pathname, x->base, x->baselen))
-			continue;
-
-		namelen = x->baselen ? pathlen - x->baselen : pathlen;
-		name = pathname + pathlen  - namelen;
-
-		/* if the non-wildcard part is longer than the
-		   remaining pathname, surely it cannot match */
-		if (prefix > namelen)
-			continue;
-
-		if (prefix) {
-			if (strncmp_icase(exclude, name, prefix))
-				continue;
-			exclude += prefix;
-			name    += prefix;
-			namelen -= prefix;
-		}
-
-		if (!fnmatch_icase(exclude, name, FNM_PATHNAME))
+		assert(x->baselen == 0 || x->base[x->baselen - 1] == '/');
+		if (match_pathname(pathname, pathlen,
+				   x->base, x->baselen ? x->baselen - 1 : 0,
+				   exclude, prefix, x->patternlen, x->flags))
 			return to_exclude;
 	}
 	return -1; /* undecided */
diff --git a/dir.h b/dir.h
index d416c5a..11d054a 100644
--- a/dir.h
+++ b/dir.h
@@ -80,6 +80,9 @@ extern int excluded_from_list(const char *pathname, int pathlen, const char *bas
 			      int *dtype, struct exclude_list *el);
 extern int match_basename(const char *, int,
 			  const char *, int, int, int);
+extern int match_pathname(const char *, int,
+			  const char *, int,
+			  const char *, int, int, int);
 struct dir_entry *dir_add_ignored(struct dir_struct *dir, const char *pathname, int len);
 
 /*
-- 
1.8.0.rc2.11.g2b79d01