Add a helper utility to compare filesystem trees

The intended use case is to compare two mounted or unpacke squashfs
images, so a repacked test image can be compared against its original
or an image unpacked with unsquashfs can be compared with an image
unpacked by rdsquashfs or sqfs2tar.

Since the tool is only intended to aid development (specifically
automated testing), it is not installed by `make install`.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 41 insertions, 0 deletions

diff --git a/difftool/difftool.h b/difftool/difftool.h
new file mode 100644
index 0000000..0dea6d5
--- /dev/null
+++ b/difftool/difftool.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * difftool.h
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#ifndef DIFFTOOL_H
+#define DIFFTOOL_H
+
+#include "config.h"
+#include "fstree.h"
+#include "util.h"
+
+#include <sys/mman.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#define MAX_WINDOW_SIZE (1024 * 1024 * 4)
+
+extern const char *first_path;
+extern const char *second_path;
+extern int compare_flags;
+
+enum {
+	COMPARE_NO_PERM = 0x01,
+	COMPARE_NO_OWNER = 0x02,
+};
+
+int compare_dir_entries(tree_node_t *a, tree_node_t *b);
+
+char *node_path(tree_node_t *n);
+
+int compare_files(file_info_t *a, file_info_t *b, const char *path);
+
+int node_compare(tree_node_t *a, tree_node_t *b);
+
+#endif /* DIFFTOOL_H */