3 files changed, 69 insertions, 1 deletions
diff --git a/lib/Makemodule.am b/lib/Makemodule.am
index 0120347..536cad0 100644
--- a/lib/Makemodule.am
+++ b/lib/Makemodule.am
@@ -1,6 +1,6 @@
 libfstree_a_SOURCES = lib/fstree/fstree.c lib/fstree/fstree_from_file.c
 libfstree_a_SOURCES += lib/fstree/fstree_sort.c lib/fstree/fstree_from_dir.c
-libfstree_a_SOURCES += include/fstree.h
+libfstree_a_SOURCES += lib/fstree/gen_inode_table.c include/fstree.h
 libfstree_a_CFLAGS = $(AM_CFLAGS)
 libfstree_a_CPPFLAGS = $(AM_CPPFLAGS)
 
diff --git a/lib/fstree/fstree.c b/lib/fstree/fstree.c
index 0c3f13d..56ca528 100644
--- a/lib/fstree/fstree.c
+++ b/lib/fstree/fstree.c
@@ -352,5 +352,6 @@ void fstree_cleanup(fstree_t *fs)
 	str_table_cleanup(&fs->xattr_keys);
 	str_table_cleanup(&fs->xattr_values);
 	free_recursive(fs->root);
+	free(fs->inode_table);
 	memset(fs, 0, sizeof(*fs));
 }
diff --git a/lib/fstree/gen_inode_table.c b/lib/fstree/gen_inode_table.c
new file mode 100644
index 0000000..2782c6d
--- /dev/null
+++ b/lib/fstree/gen_inode_table.c
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "fstree.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+
+static size_t count_nodes(tree_node_t *root)
+{
+	tree_node_t *n = root->data.dir->children;
+	size_t count = 1;
+
+	while (n != NULL) {
+		if (S_ISDIR(n->mode)) {
+			count += count_nodes(n);
+		} else {
+			++count;
+		}
+		n = n->next;
+	}
+
+	return count;
+}
+
+static void map_child_nodes(fstree_t *fs, tree_node_t *root, size_t *counter)
+{
+	bool has_subdirs = false;
+	tree_node_t *it;
+
+	for (it = root->data.dir->children; it != NULL; it = it->next) {
+		if (S_ISDIR(it->mode)) {
+			has_subdirs = true;
+			break;
+		}
+	}
+
+	if (has_subdirs) {
+		for (it = root->data.dir->children; it != NULL; it = it->next) {
+			if (S_ISDIR(it->mode))
+				map_child_nodes(fs, it, counter);
+		}
+	}
+
+	for (it = root->data.dir->children; it != NULL; it = it->next) {
+		it->inode_num = *counter;
+		*counter += 1;
+
+		fs->inode_table[it->inode_num] = it;
+	}
+}
+
+int fstree_gen_inode_table(fstree_t *fs)
+{
+	size_t inum = 2;
+
+	fs->inode_tbl_size = count_nodes(fs->root) + 2;
+	fs->inode_table = calloc(sizeof(tree_node_t *), fs->inode_tbl_size);
+
+	if (fs->inode_table == NULL) {
+		perror("allocating inode table");
+		return -1;
+	}
+
+	map_child_nodes(fs, fs->root, &inum);
+	fs->root->inode_num = inum;
+	fs->inode_table[inum] = fs->root;
+	return 0;
+}