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-rw-r--r--e2fslib/ext2_ext_attr.h58
1 files changed, 58 insertions, 0 deletions
diff --git a/e2fslib/ext2_ext_attr.h b/e2fslib/ext2_ext_attr.h
new file mode 100644
index 0000000..504f747
--- /dev/null
+++ b/e2fslib/ext2_ext_attr.h
@@ -0,0 +1,58 @@
+/*
+ File: linux/ext2_ext_attr.h
+
+ On-disk format of extended attributes for the ext2 filesystem.
+
+ (C) 2000 Andreas Gruenbacher, <a.gruenbacher@computer.org>
+*/
+
+/* Magic value in attribute blocks */
+#define EXT2_EXT_ATTR_MAGIC 0xEA010000
+
+/* Maximum number of references to one attribute block */
+#define EXT2_EXT_ATTR_REFCOUNT_MAX 1024
+
+struct ext2_ext_attr_header {
+ __u32 h_magic; /* magic number for identification */
+ __u32 h_refcount; /* reference count */
+ __u32 h_blocks; /* number of disk blocks used */
+ __u32 h_hash; /* hash value of all attributes */
+ __u32 h_reserved[4]; /* zero right now */
+};
+
+struct ext2_ext_attr_entry {
+ __u8 e_name_len; /* length of name */
+ __u8 e_name_index; /* index into table of names (n/i) */
+ __u16 e_value_offs; /* offset in disk block of value */
+ __u32 e_value_block; /* disk block attribute is stored on (n/i) */
+ __u32 e_value_size; /* size of attribute value */
+ __u32 e_hash; /* hash value of name and value */
+ char e_name[0]; /* attribute name */
+};
+
+#define EXT2_EXT_ATTR_PAD_BITS 2
+#define EXT2_EXT_ATTR_PAD (1<<EXT2_EXT_ATTR_PAD_BITS)
+#define EXT2_EXT_ATTR_ROUND (EXT2_EXT_ATTR_PAD-1)
+#define EXT2_EXT_ATTR_LEN(name_len) \
+ (((name_len) + EXT2_EXT_ATTR_ROUND + \
+ sizeof(struct ext2_ext_attr_entry)) & ~EXT2_EXT_ATTR_ROUND)
+#define EXT2_EXT_ATTR_NEXT(entry) \
+ ( (struct ext2_ext_attr_entry *)( \
+ (char *)(entry) + EXT2_EXT_ATTR_LEN((entry)->e_name_len)) )
+#define EXT2_EXT_ATTR_SIZE(size) \
+ (((size) + EXT2_EXT_ATTR_ROUND) & ~EXT2_EXT_ATTR_ROUND)
+
+#ifdef __KERNEL__
+# ifdef CONFIG_EXT2_FS_EXT_ATTR
+extern int ext2_get_ext_attr(struct inode *, const char *, char *, size_t, int);
+extern int ext2_set_ext_attr(struct inode *, const char *, char *, size_t, int);
+extern void ext2_ext_attr_free_inode(struct inode *inode);
+extern void ext2_ext_attr_put_super(struct super_block *sb);
+extern int ext2_ext_attr_init(void);
+extern void ext2_ext_attr_done(void);
+# else
+# define ext2_get_ext_attr NULL
+# define ext2_set_ext_attr NULL
+# endif
+#endif /* __KERNEL__ */
+