[PATCH 0/3] stop storing trailing slash in dir-hash

@@ -890,7 +890,7 @@ enum exist_status {
  */
 static enum exist_status directory_exists_in_index_icase(const char *dirname, int len)
 {
-	const struct cache_entry *ce = cache_dir_exists(dirname, len + 1);
+	const struct cache_entry *ce = cache_dir_exists(dirname, len);
 	unsigned char endchar;
 
 	if (!ce)

@@ -58,9 +58,9 @@ static struct dir_entry *hash_dir_entry(struct index_state *istate,
 {
 	/*
 	 * Throw each directory component in the hash for quick lookup
-	 * during a git status. Directory components are stored with their
+	 * during a git status. Directory components are stored without their
 	 * closing slash.  Despite submodules being a directory, they never
-	 * reach this point, because they are stored without a closing slash
+	 * reach this point, because they are stored
 	 * in index_state.name_hash (as ordinary cache_entries).
 	 *
 	 * Note that the cache_entry stored with the dir_entry merely

@@ -78,6 +78,7 @@ static struct dir_entry *hash_dir_entry(struct index_state *istate,
 		namelen--;
 	if (namelen <= 0)
 		return NULL;
+	namelen--;
 
 	/* lookup existing entry for that directory */
 	dir = find_dir_entry(istate, ce->name, namelen);

@@ -97,7 +98,7 @@ static struct dir_entry *hash_dir_entry(struct index_state *istate,
 		}
 
 		/* recursively add missing parent directories */
-		dir->parent = hash_dir_entry(istate, ce, namelen - 1);
+		dir->parent = hash_dir_entry(istate, ce, namelen);
 	}
 	return dir;
 }

@@ -237,7 +238,7 @@ struct cache_entry *index_dir_exists(struct index_state *istate, const char *nam
 	 * in the dir-hash, submodules are stored in the name-hash, so check
 	 * there, as well.
 	 */
-	ce = index_name_exists(istate, name, namelen - 1, 1);
+	ce = index_name_exists(istate, name, namelen, 1);
 	if (ce && S_ISGITLINK(ce->ce_mode))
 		return ce;
 

@@ -643,7 +643,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 			if (*ptr == '/') {
 				struct cache_entry *foundce;
 				++ptr;
-				foundce = index_dir_exists(istate, ce->name, ptr - ce->name);
+				foundce = index_dir_exists(istate, ce->name, ptr - ce->name - 1);
 				if (foundce) {
 					memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr);
 					startPtr = ptr;

@@ -314,6 +314,7 @@ extern void free_name_hash(struct index_state *istate);
 #define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL, NULL)
 #define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
 #define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
+#define cache_dir_exists(name, namelen) index_dir_exists(&the_index, (name), (namelen))
 #define cache_name_exists(name, namelen, igncase) index_name_exists(&the_index, (name), (namelen), (igncase))
 #define cache_name_is_other(name, namelen) index_name_is_other(&the_index, (name), (namelen))
 #define resolve_undo_clear() resolve_undo_clear_index(&the_index)

@@ -463,6 +464,7 @@ extern int write_index(struct index_state *, int newfd);
 extern int discard_index(struct index_state *);
 extern int unmerged_index(const struct index_state *);
 extern int verify_path(const char *path);
+extern struct cache_entry *index_dir_exists(struct index_state *istate, const char *name, int namelen);
 extern struct cache_entry *index_name_exists(struct index_state *istate, const char *name, int namelen, int igncase);
 extern int index_name_pos(const struct index_state *, const char *name, int namelen);
 #define ADD_CACHE_OK_TO_ADD 1		/* Ok to add */

@@ -860,7 +860,8 @@ static struct dir_entry *dir_entry_new(const char *pathname, int len)
 
 static struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathname, int len)
 {
-	if (cache_name_exists(pathname, len, ignore_case))
+	if ((len == 0 || pathname[len - 1] != '/') &&
+	    cache_name_exists(pathname, len, ignore_case))
 		return NULL;
 
 	ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);

@@ -885,11 +886,11 @@ enum exist_status {
 /*
  * Do not use the alphabetically sorted index to look up
  * the directory name; instead, use the case insensitive
- * name hash.
+ * directory hash.
  */
 static enum exist_status directory_exists_in_index_icase(const char *dirname, int len)
 {
-	const struct cache_entry *ce = cache_name_exists(dirname, len + 1, ignore_case);
+	const struct cache_entry *ce = cache_dir_exists(dirname, len + 1);
 	unsigned char endchar;
 
 	if (!ce)

@@ -222,11 +222,35 @@ static int same_name(const struct cache_entry *ce, const char *name, int namelen
 	return slow_same_name(name, namelen, ce->name, len);
 }
 
+struct cache_entry *index_dir_exists(struct index_state *istate, const char *name, int namelen)
+{
+	struct cache_entry *ce;
+	struct dir_entry *dir;
+
+	lazy_init_name_hash(istate);
+	dir = find_dir_entry(istate, name, namelen);
+	if (dir && dir->nr)
+		return dir->ce;
+
+	/*
+	 * It might be a submodule. Unlike plain directories, which are stored
+	 * in the dir-hash, submodules are stored in the name-hash, so check
+	 * there, as well.
+	 */
+	ce = index_name_exists(istate, name, namelen - 1, 1);
+	if (ce && S_ISGITLINK(ce->ce_mode))
+		return ce;
+
+	return NULL;
+}
+
 struct cache_entry *index_name_exists(struct index_state *istate, const char *name, int namelen, int icase)
 {
 	unsigned int hash = hash_name(name, namelen);
 	struct cache_entry *ce;
 
+	assert(namelen == 0 || name[namelen - 1] != '/');
+
 	lazy_init_name_hash(istate);
 	ce = lookup_hash(hash, &istate->name_hash);
 

@@ -237,29 +261,6 @@ struct cache_entry *index_name_exists(struct index_state *istate, const char *na
 		}
 		ce = ce->next;
 	}
-
-	/*
-	 * When looking for a directory (trailing '/'), it might be a
-	 * submodule or a directory. Despite submodules being directories,
-	 * they are stored in the name hash without a closing slash.
-	 * When ignore_case is 1, directories are stored in a separate hash
-	 * table *with* their closing slash.
-	 *
-	 * The side effect of this storage technique is we have need to
-	 * lookup the directory in a separate hash table, and if not found
-	 * remove the slash from name and perform the lookup again without
-	 * the slash.  If a match is made, S_ISGITLINK(ce->mode) will be
-	 * true.
-	 */
-	if (icase && name[namelen - 1] == '/') {
-		struct dir_entry *dir = find_dir_entry(istate, name, namelen);
-		if (dir && dir->nr)
-			return dir->ce;
-
-		ce = index_name_exists(istate, name, namelen - 1, icase);
-		if (ce && S_ISGITLINK(ce->ce_mode))
-			return ce;
-	}
 	return NULL;
 }
 

@@ -643,7 +643,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 			if (*ptr == '/') {
 				struct cache_entry *foundce;
 				++ptr;
-				foundce = index_name_exists(istate, ce->name, ptr - ce->name, ignore_case);
+				foundce = index_dir_exists(istate, ce->name, ptr - ce->name);
 				if (foundce) {
 					memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr);
 					startPtr = ptr;

@@ -1161,21 +1161,9 @@ static enum path_treatment treat_one_path(struct dir_struct *dir,
 	 */
 	if ((dir->flags & DIR_COLLECT_KILLED_ONLY) &&
 	    (dtype == DT_DIR) &&
-	    !has_path_in_index) {
-		/*
-		 * NEEDSWORK: directory_exists_in_index_icase()
-		 * assumes that one byte past the given path is
-		 * readable and has '/', which needs to be fixed, but
-		 * until then, work it around in the caller.
-		 */
-		strbuf_addch(path, '/');
-		if (directory_exists_in_index(path->buf, path->len - 1) ==
-		    index_nonexistent) {
-			strbuf_setlen(path, path->len - 1);
-			return path_none;
-		}
-		strbuf_setlen(path, path->len - 1);
-	}
+	    !has_path_in_index &&
+	    (directory_exists_in_index(path->buf, path->len) == index_nonexistent))
+		return path_none;
 
 	exclude = is_excluded(dir, path->buf, &dtype);