Patch format

2014-01-06 23:10:17 +00:00 · 2014-01-06 23:10:17 +00:00 · d891ecbf1d
parent 310547b6b8
commit d891ecbf1d
1 changed files with 7 additions and 0 deletions
--- a/patch_io.c
+++ b/patch_io.c
@ -2,6 +2,13 @@
 * patch_io.c --- This is the "patch" io manager that writes the new data into
 * a separate sparse file to apply it later.
 *
+ * Patch file format:
+ * 1) sparse data blocks - same size as the filesystem image, but only changed blocks are written
+ * 2) updated block bitmap - fs_size/block_size/8
+ * 3) 4 byte FS block size
+ * 4) 4 byte FS size in blocks
+ *    FIXME: should be 8 bytes! 4 bytes = sizeof(blk_t), from ext2fs_get_device_size()
+ *
 * Copyright (c) Vitaliy Filippov <vitalif@mail.ru> 2014
 * License: GNU GPLv2 or later
 *