1 files changed, 68 insertions, 0 deletions
diff --git a/lib/ext2fs/valid_blk.c b/lib/ext2fs/valid_blk.c
new file mode 100644
index 0000000..db5d90a
--- /dev/null
+++ b/lib/ext2fs/valid_blk.c
@@ -0,0 +1,68 @@
+/*
+ * valid_blk.c --- does the inode have valid blocks?
+ *
+ * Copyright 1997 by Theodore Ts'o
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#include <stdio.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <string.h>
+#include <time.h>
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+
+/*
+ * This function returns 1 if the inode's block entries actually
+ * contain block entries.
+ */
+int ext2fs_inode_has_valid_blocks2(ext2_filsys fs, struct ext2_inode *inode)
+{
+	/*
+	 * Only directories, regular files, and some symbolic links
+	 * have valid block entries.
+	 */
+	if (!LINUX_S_ISDIR(inode->i_mode) && !LINUX_S_ISREG(inode->i_mode) &&
+	    !LINUX_S_ISLNK(inode->i_mode))
+		return 0;
+
+	/*
+	 * If the symbolic link is a "fast symlink", then the symlink
+	 * target is stored in the block entries.
+	 */
+	if (LINUX_S_ISLNK (inode->i_mode)) {
+		if (ext2fs_file_acl_block(fs, inode) == 0) {
+			/* With no EA block, we can rely on i_blocks */
+			if (inode->i_blocks == 0)
+				return 0;
+		} else {
+			/* With an EA block, life gets more tricky */
+			if (inode->i_size >= EXT2_N_BLOCKS*4)
+				return 1; /* definitely using i_block[] */
+			if (inode->i_size > 4 && inode->i_block[1] == 0)
+				return 1; /* definitely using i_block[] */
+			return 0; /* Probably a fast symlink */
+		}
+	}
+
+	/*
+	 * If this inode has inline data, it shouldn't have valid block
+	 * entries.
+	 */
+	if (inode->i_flags & EXT4_INLINE_DATA_FL)
+		return 0;
+	return 1;
+}
+
+int ext2fs_inode_has_valid_blocks(struct ext2_inode *inode)
+{
+	return ext2fs_inode_has_valid_blocks2(NULL, inode);
+}