There is a bit of redundancy here, as we already know the weights of
btree's inner-branches from their parents. But in theory sharing the
same encoding for both the top level btree reference and inner-branches
should offer more chance for deduplication and hopefully less code.
This also moves some members around in the btree encoding so that the
redund blocks are at the beginning. This _might_ simplify decoding of
the variable-length redund blocks at some point.
Current btree encoding:
.----+----+----+----.
| blocks ... redund leb128s (1-20 bytes)
: :
|----+----+----+----|
| trunk ... 1 leb128 (1-5 bytes)
|----+----+----+----|
| weight ... 1 leb128 (1-5 bytes)
|----+----+----+----|
| cksum | 1 le32 (4 bytes)
'----+----+----+----'
This also partially reverts some tag name changes:
- BNAME -> BRANCH
- DMARK -> BOOKMARK
Christopher Haster
256430213d