mufs: implement mufs_unlink()

include/fs/mufs.h

@@ -56,3 +56,4 @@ void mufs_close(struct mufs_file *file);
 long mufs_seek(struct mufs_file *file, long offset, int whence);
 size_t mufs_read(struct mufs_file *file, void *data, size_t len);
 size_t mufs_write(struct mufs_file *file, const void *data, size_t len);
+int mufs_unlink(struct mufs *fs, const char *path);

source/fs/mufs/file.c

@@ -116,3 +116,20 @@ size_t mufs_write(struct mufs_file *file, const void *data, size_t len)
 
 	return ret;
 }
+
+int mufs_unlink(struct mufs *fs, const char *path)
+{
+	struct mufs_stat stat;
+	struct mufs_tree *tree;
+
+	if (!(tree = resolve_path(fs, path, &stat)))
+		return -1;
+
+	if (stat.type != MUFS_FILE)
+		return -1;
+
+	if (mufs_shrink_tree(tree, 0) < 0)
+		return -1;
+
+	return mufs_rmpath(fs, path);
+}