1 files changed, 57 insertions, 0 deletions

diff --git a/e2fsprogs/ext2fs/valid_blk.c b/e2fsprogs/ext2fs/valid_blk.c
new file mode 100644
index 000000000..8ed77ae2a
--- /dev/null
+++ b/e2fsprogs/ext2fs/valid_blk.c
@@ -0,0 +1,57 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * 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 Public
+ * License.
+ * %End-Header%
+ *
+ */
+
+#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_blocks(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 (inode->i_file_acl == 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 */
+                }
+        }
+        return 1;
+}