[PATCH v10 5/5] remove_subtree(): reimplement using iterators

[Daniel Ferreira <bnmvco@gmail.com>]

Use dir_iterator to traverse through remove_subtree()'s directory tree,
avoiding the need for recursive calls to readdir(). Simplify
remove_subtree()'s code.

A conversion similar in purpose was previously done at 46d092a
("for_each_reflog(): reimplement using iterators", 2016-05-21).

Signed-off-by: Daniel Ferreira <bnmvco@gmail.com>
---
 entry.c | 42 ++++++++++++++++--------------------------
 1 file changed, 16 insertions(+), 26 deletions(-)

diff --git a/entry.c b/entry.c
index d2b512d..a939432 100644
--- a/entry.c
+++ b/entry.c
@@ -3,6 +3,8 @@
 #include "dir.h"
 #include "streaming.h"
 #include "submodule.h"
+#include "iterator.h"
+#include "dir-iterator.h"
 
 static void create_directories(const char *path, int path_len,
 			       const struct checkout *state)
@@ -45,33 +47,21 @@ static void create_directories(const char *path, int path_len,
 	free(buf);
 }
 
-static void remove_subtree(struct strbuf *path)
+static void remove_subtree(const char *path)
 {
-	DIR *dir = opendir(path->buf);
-	struct dirent *de;
-	int origlen = path->len;
-
-	if (!dir)
-		die_errno("cannot opendir '%s'", path->buf);
-	while ((de = readdir(dir)) != NULL) {
-		struct stat st;
-
-		if (is_dot_or_dotdot(de->d_name))
-			continue;
-
-		strbuf_addch(path, '/');
-		strbuf_addstr(path, de->d_name);
-		if (lstat(path->buf, &st))
-			die_errno("cannot lstat '%s'", path->buf);
-		if (S_ISDIR(st.st_mode))
-			remove_subtree(path);
-		else if (unlink(path->buf))
-			die_errno("cannot unlink '%s'", path->buf);
-		strbuf_setlen(path, origlen);
+	struct dir_iterator *diter = dir_iterator_begin(path,
+		DIR_ITERATOR_POST_ORDER_TRAVERSAL | DIR_ITERATOR_LIST_ROOT_DIR);
+	if (!diter) {
+		die_errno("cannot remove path '%s'", path);
+	}
+
+	while (dir_iterator_advance(diter) == ITER_OK) {
+		if (S_ISDIR(diter->st.st_mode)) {
+			if (rmdir(diter->path.buf))
+				die_errno("cannot rmdir '%s'", diter->path.buf);
+		} else if (unlink(diter->path.buf))
+			die_errno("cannot unlink '%s'", diter->path.buf);
 	}
-	closedir(dir);
-	if (rmdir(path->buf))
-		die_errno("cannot rmdir '%s'", path->buf);
 }
 
 static int create_file(const char *path, unsigned int mode)
@@ -312,7 +302,7 @@ int checkout_entry(struct cache_entry *ce,
 				return 0;
 			if (!state->force)
 				return error("%s is a directory", path.buf);
-			remove_subtree(&path);
+			remove_subtree(path.buf);
 		} else if (unlink(path.buf))
 			return error_errno("unable to unlink old '%s'", path.buf);
 	} else if (state->not_new)
-- 
2.7.4 (Apple Git-66)