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-rw-r--r--lib/ext2fs/ext2_ext_attr.h84
1 files changed, 84 insertions, 0 deletions
diff --git a/lib/ext2fs/ext2_ext_attr.h b/lib/ext2fs/ext2_ext_attr.h
new file mode 100644
index 0000000..c6068c4
--- /dev/null
+++ b/lib/ext2fs/ext2_ext_attr.h
@@ -0,0 +1,84 @@
+/*
+ File: linux/ext2_ext_attr.h
+
+ On-disk format of extended attributes for the ext2 filesystem.
+
+ (C) 2000 Andreas Gruenbacher, <a.gruenbacher@computer.org>
+*/
+
+#ifndef _EXT2_EXT_ATTR_H
+#define _EXT2_EXT_ATTR_H
+/* Magic value in attribute blocks */
+#define EXT2_EXT_ATTR_MAGIC_v1 0xEA010000
+#define EXT2_EXT_ATTR_MAGIC 0xEA020000
+
+/* 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_checksum; /* crc32c(uuid+id+xattrs) */
+ /* id = inum if refcount = 1, else blknum */
+ __u32 h_reserved[3]; /* zero right now */
+};
+
+struct ext2_ext_attr_entry {
+ __u8 e_name_len; /* length of name */
+ __u8 e_name_index; /* attribute name index */
+ __u16 e_value_offs; /* offset in disk block of value */
+ __u32 e_value_inum; /* inode in which the value is stored */
+ __u32 e_value_size; /* size of attribute value */
+ __u32 e_hash; /* hash value of name and value */
+#if 0
+ char e_name[0]; /* attribute name */
+#endif
+};
+
+#define EXT2_EXT_ATTR_PAD_BITS 2
+#define EXT2_EXT_ATTR_PAD ((unsigned) 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)
+#define EXT2_EXT_IS_LAST_ENTRY(entry) (*((__u32 *)(entry)) == 0UL)
+#define EXT2_EXT_ATTR_NAME(entry) \
+ (((char *) (entry)) + sizeof(struct ext2_ext_attr_entry))
+#define EXT2_XATTR_LEN(name_len) \
+ (((name_len) + EXT2_EXT_ATTR_ROUND + \
+ sizeof(struct ext2_xattr_entry)) & ~EXT2_EXT_ATTR_ROUND)
+#define EXT2_XATTR_SIZE(size) \
+ (((size) + EXT2_EXT_ATTR_ROUND) & ~EXT2_EXT_ATTR_ROUND)
+
+/*
+ * XATTR_SIZE_MAX is currently 64k, but for the purposes of checking
+ * for file system consistency errors, we use a somewhat bigger value.
+ * This allows XATTR_SIZE_MAX to grow in the future, but by using this
+ * instead of INT_MAX for certain consistency checks, we don't need to
+ * worry about arithmetic overflows. (Actually XATTR_SIZE_MAX is
+ * defined in include/uapi/linux/limits.h, so changing it is going
+ * not going to be trivial....)
+ */
+#define EXT2_XATTR_SIZE_MAX (1 << 24)
+
+#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__ */
+#endif /* _EXT2_EXT_ATTR_H */