README: Reorder, add sections and extract stuff into FILEFORMAT file.

1 files changed, 42 insertions, 0 deletions

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+Version 0
+---------
+
+Following sections explain internals of metastore file (.metadata).
+
+
+### Data types
+
+    CSTRING     = NUL-terminated binary string
+    BSTRING(N)  = binary string of length N
+    INT(N)      = N byte integer in big endian byte order
+
+
+### File layout
+
+    HEADER
+    N * ENTRY
+
+
+### HEADER format
+
+    BSTRING(10) - Magic header - "MeTaSt00r3"
+    BSTRING(8)  - Version - "\0\0\0\0\0\0\0\0" (currently)
+
+
+### ENTRY format
+
+    CSTRING     - Path  (absolute or relative)
+    CSTRING     - Owner (owner name, not uid)
+    CSTRING     - Group (group name, not gid)
+
+    INT(8)      - Mtime (seconds)
+    INT(8)      - Mtime (nanoseconds)
+    INT(2)      - Mode  (st_mode from struct stat st_mode AND 0177777,
+                         i.e. unix permissions and type of file)
+
+    INT(4)      - num_xattrs
+    FOR (i = 0; i < num_xattrs; i++) {
+        CSTRING            - xattr name
+        INT(4)             - xattrlen
+        BSTRING(xattrlen)  - xattr value
+    }