hfsplus: add on-disk layout declarations related to attributes tree

index 921967e..452ede0 100644
@@ -52,13 +52,23 @@
 typedef __be32 hfsplus_cnid;
 typedef __be16 hfsplus_unichr;
 
+#define HFSPLUS_MAX_STRLEN 255
+#define HFSPLUS_ATTR_MAX_STRLEN 127
+
 /* A "string" as used in filenames, etc. */
 struct hfsplus_unistr {
 	__be16 length;
-	hfsplus_unichr unicode[255];
+	hfsplus_unichr unicode[HFSPLUS_MAX_STRLEN];
 } __packed;
 
-#define HFSPLUS_MAX_STRLEN 255
+/*
+ * A "string" is used in attributes file
+ * for name of extended attribute
+ */
+struct hfsplus_attr_unistr {
+	__be16 length;
+	hfsplus_unichr unicode[HFSPLUS_ATTR_MAX_STRLEN];
+} __packed;
 
 /* POSIX permissions */
 struct hfsplus_perm {

@@ -291,6 +301,8 @@ struct hfsplus_cat_file {
 /* File attribute bits */
 #define HFSPLUS_FILE_LOCKED		0x0001
 #define HFSPLUS_FILE_THREAD_EXISTS	0x0002
+#define HFSPLUS_XATTR_EXISTS		0x0004
+#define HFSPLUS_ACL_EXISTS		0x0008
 
 /* HFS+ catalog thread (part of a cat_entry) */
 struct hfsplus_cat_thread {

@@ -327,11 +339,63 @@ struct hfsplus_ext_key {
 
 #define HFSPLUS_EXT_KEYLEN	sizeof(struct hfsplus_ext_key)
 
+#define HFSPLUS_XATTR_FINDER_INFO_NAME "com.apple.FinderInfo"
+#define HFSPLUS_XATTR_ACL_NAME "com.apple.system.Security"
+
+#define HFSPLUS_ATTR_INLINE_DATA 0x10
+#define HFSPLUS_ATTR_FORK_DATA   0x20
+#define HFSPLUS_ATTR_EXTENTS     0x30
+
+/* HFS+ attributes tree key */
+struct hfsplus_attr_key {
+	__be16 key_len;
+	__be16 pad;
+	hfsplus_cnid cnid;
+	__be32 start_block;
+	struct hfsplus_attr_unistr key_name;
+} __packed;
+
+#define HFSPLUS_ATTR_KEYLEN	sizeof(struct hfsplus_attr_key)
+
+/* HFS+ fork data attribute */
+struct hfsplus_attr_fork_data {
+	__be32 record_type;
+	__be32 reserved;
+	struct hfsplus_fork_raw the_fork;
+} __packed;
+
+/* HFS+ extension attribute */
+struct hfsplus_attr_extents {
+	__be32 record_type;
+	__be32 reserved;
+	struct hfsplus_extent extents;
+} __packed;
+
+#define HFSPLUS_MAX_INLINE_DATA_SIZE 3802
+
+/* HFS+ attribute inline data */
+struct hfsplus_attr_inline_data {
+	__be32 record_type;
+	__be32 reserved1;
+	u8 reserved2[6];
+	__be16 length;
+	u8 raw_bytes[HFSPLUS_MAX_INLINE_DATA_SIZE];
+} __packed;
+
+/* A data record in the attributes tree */
+typedef union {
+	__be32 record_type;
+	struct hfsplus_attr_fork_data fork_data;
+	struct hfsplus_attr_extents extents;
+	struct hfsplus_attr_inline_data inline_data;
+} __packed hfsplus_attr_entry;
+
 /* HFS+ generic BTree key */
 typedef union {
 	__be16 key_len;
 	struct hfsplus_cat_key cat;
 	struct hfsplus_ext_key ext;
+	struct hfsplus_attr_key attr;
 } __packed hfsplus_btree_key;
 
 #endif