Introduce remove_dir_recursively()

There was a function called remove_empty_dir_recursive() buried
in refs.c.  Expose a slightly enhanced version in dir.h: it can now
optionally remove a non-empty directory.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

dir.c

@@ -685,3 +685,44 @@ int is_inside_dir(const char *dir)
 	char buffer[PATH_MAX];
 	return get_relative_cwd(buffer, sizeof(buffer), dir) != NULL;
 }
+
+int remove_dir_recursively(struct strbuf *path, int only_empty)
+{
+	DIR *dir = opendir(path->buf);
+	struct dirent *e;
+	int ret = 0, original_len = path->len, len;
+
+	if (!dir)
+		return -1;
+	if (path->buf[original_len - 1] != '/')
+		strbuf_addch(path, '/');
+
+	len = path->len;
+	while ((e = readdir(dir)) != NULL) {
+		struct stat st;
+		if ((e->d_name[0] == '.') &&
+		    ((e->d_name[1] == 0) ||
+		     ((e->d_name[1] == '.') && e->d_name[2] == 0)))
+			continue; /* "." and ".." */
+
+		strbuf_setlen(path, len);
+		strbuf_addstr(path, e->d_name);
+		if (lstat(path->buf, &st))
+			; /* fall thru */
+		else if (S_ISDIR(st.st_mode)) {
+			if (!remove_dir_recursively(path, only_empty))
+				continue; /* happy */
+		} else if (!only_empty && !unlink(path->buf))
+			continue; /* happy, too */
+
+		/* path too long, stat fails, or non-directory still exists */
+		ret = -1;
+		break;
+	}
+	closedir(dir);
+
+	strbuf_setlen(path, original_len);
+	if (!ret)
+		ret = rmdir(path->buf);
+	return ret;
+}

dir.h

@@ -64,4 +64,6 @@ extern struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathna
 extern char *get_relative_cwd(char *buffer, int size, const char *dir);
 extern int is_inside_dir(const char *dir);
 
+extern int remove_dir_recursively(struct strbuf *path, int only_empty);
+
 #endif

refs.c

@@ -2,6 +2,7 @@
 #include "refs.h"
 #include "object.h"
 #include "tag.h"
+#include "dir.h"
 
 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
 #define REF_KNOWS_PEELED 04
@@ -671,57 +672,23 @@ static struct ref_lock *verify_lock(struct ref_lock *lock,
 	return lock;
 }
 
-static int remove_empty_dir_recursive(char *path, int len)
-{
-	DIR *dir = opendir(path);
-	struct dirent *e;
-	int ret = 0;
-
-	if (!dir)
-		return -1;
-	if (path[len-1] != '/')
-		path[len++] = '/';
-	while ((e = readdir(dir)) != NULL) {
-		struct stat st;
-		int namlen;
-		if ((e->d_name[0] == '.') &&
-		    ((e->d_name[1] == 0) ||
-		     ((e->d_name[1] == '.') && e->d_name[2] == 0)))
-			continue; /* "." and ".." */
-
-		namlen = strlen(e->d_name);
-		if ((len + namlen < PATH_MAX) &&
-		    strcpy(path + len, e->d_name) &&
-		    !lstat(path, &st) &&
-		    S_ISDIR(st.st_mode) &&
-		    !remove_empty_dir_recursive(path, len + namlen))
-			continue; /* happy */
-
-		/* path too long, stat fails, or non-directory still exists */
-		ret = -1;
-		break;
-	}
-	closedir(dir);
-	if (!ret) {
-		path[len] = 0;
-		ret = rmdir(path);
-	}
-	return ret;
-}
-
-static int remove_empty_directories(char *file)
+static int remove_empty_directories(const char *file)
 {
 	/* we want to create a file but there is a directory there;
 	 * if that is an empty directory (or a directory that contains
 	 * only empty directories), remove them.
 	 */
-	char path[PATH_MAX];
-	int len = strlen(file);
+	struct strbuf path;
+	int result;
 
-	if (len >= PATH_MAX) /* path too long ;-) */
-		return -1;
-	strcpy(path, file);
-	return remove_empty_dir_recursive(path, len);
+	strbuf_init(&path, 20);
+	strbuf_addstr(&path, file);
+
+	result = remove_dir_recursively(&path, 1);
+
+	strbuf_release(&path);
+
+	return result;
 }
 
 static int is_refname_available(const char *ref, const char *oldref,