:py:mod:`dissect.volume.dm.c_dm`
================================

.. py:module:: dissect.volume.dm.c_dm


Module Contents
---------------

.. py:data:: dm_def
   :value: Multiline-String

    .. raw:: html

        <details><summary>Show Value</summary>

    .. code-block:: python

        """
        /* DM BTree */
        enum node_flags {
            INTERNAL_NODE = 1,
            LEAF_NODE = 1 << 1
        };
        
        /*
         * Every btree node begins with this structure.  Make sure it's a multiple
         * of 8-bytes in size, otherwise the 64bit keys will be mis-aligned.
         */
        struct node_header {
            uint32  csum;
            uint32  flags;
            uint64  blocknr;                /* Block this node is supposed to live in. */
        
            uint32  nr_entries;
            uint32  max_entries;
            uint32  value_size;
            uint32  padding;
        };
        
        struct btree_node {
            struct node_header header;
            // uint64 keys[];
        };
        
        /* Thin */
        #define THIN_SUPERBLOCK_MAGIC 27022010
        #define THIN_SUPERBLOCK_LOCATION 0
        #define THIN_VERSION 2
        #define SECTOR_TO_BLOCK_SHIFT 3
        
        /* This should be plenty */
        #define SPACE_MAP_ROOT_SIZE 128
        
        /*
         * Little endian on-disk superblock and device details.
         */
        struct thin_disk_superblock {
            uint32  csum;                   /* Checksum of superblock except for this field. */
            uint32  flags;
            uint64  blocknr;                /* This block number, dm_block_t. */
        
            uint8   uuid[16];
            uint64  magic;
            uint32  version;
            uint32  time;
        
            uint64  trans_id;
        
            /*
             * Root held by userspace transactions.
             */
            uint64  held_root;
        
            uint8   data_space_map_root[SPACE_MAP_ROOT_SIZE];
            uint8   metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
        
            /*
             * 2-level btree mapping (dev_id, (dev block, time)) -> data block
             */
            uint64  data_mapping_root;
        
            /*
             * Device detail root mapping dev_id -> device_details
             */
            uint64  device_details_root;
        
            uint32  data_block_size;        /* In 512-byte sectors. */
        
            uint32  metadata_block_size;    /* In 512-byte sectors. */
            uint64  metadata_nr_blocks;
        
            uint32  compat_flags;
            uint32  compat_ro_flags;
            uint32  incompat_flags;
        };
        
        struct disk_device_details {
            uint64 mapped_blocks;
            uint64 transaction_id;          /* When created. */
            uint32 creation_time;
            uint32 snapshotted_time;
        };
        """

    .. raw:: html

        </details>

   

.. py:data:: c_dm

   

.. py:data:: SECTOR_SIZE
   :value: 512