nimbus-eth1/nimbus/db/aristo/aristo_desc/desc_structural.nim

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Nim

# nimbus-eth1
# Copyright (c) 2023-2024 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
# http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or
# http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed
# except according to those terms.
## Aristo DB -- Patricia Trie structural data types
## ================================================
##
{.push raises: [].}
import
std/[hashes, tables],
eth/common,
"."/[desc_error, desc_identifiers]
type
LeafTiePayload* = object
## Generalised key-value pair for a sub-trie. The main trie is the
## sub-trie with `root=VertexID(1)`.
leafTie*: LeafTie ## Full `Patricia Trie` path root-to-leaf
payload*: PayloadRef ## Leaf data payload (see below)
VertexType* = enum
## Type of `Aristo Trie` vertex
Leaf
Extension
Branch
AristoAccount* = object
## Application relevant part of an Ethereum account. Note that the storage
## data/tree reference is not part of the account (see `PayloadRef` below.)
nonce*: AccountNonce ## Some `uint64` type
balance*: UInt256
codeHash*: Hash256
PayloadType* = enum
## Type of leaf data.
RawData ## Generic data
AccountData ## `Aristo account` with vertex IDs links
PayloadRef* = ref object of RootRef
## The payload type depends on the sub-tree used. The `VertesID(1)` rooted
## sub-tree only has `AccountData` type payload, while all other sub-trees
## have `RawData` payload.
case pType*: PayloadType
of RawData:
rawBlob*: Blob ## Opaque data, default value
of AccountData:
account*: AristoAccount
stoID*: VertexID ## Storage vertex ID (if any)
VertexRef* = ref object of RootRef
## Vertex for building a hexary Patricia or Merkle Patricia Trie
case vType*: VertexType
of Leaf:
lPfx*: NibblesBuf ## Portion of path segment
lData*: PayloadRef ## Reference to data payload
of Extension:
ePfx*: NibblesBuf ## Portion of path segment
eVid*: VertexID ## Edge to vertex with ID `eVid`
of Branch:
bVid*: array[16,VertexID] ## Edge list with vertex IDs
NodeRef* = ref object of VertexRef
## Combined record for a *traditional* ``Merkle Patricia Tree` node merged
## with a structural `VertexRef` type object.
error*: AristoError ## Used for error signalling in RLP decoder
key*: array[16,HashKey] ## Merkle hash/es for vertices
# ----------------------
VidVtxPair* = object
## Handy helper structure
vid*: VertexID ## Table lookup vertex ID (if any)
vtx*: VertexRef ## Reference to vertex
SavedState* = object
## Last saved state
key*: Hash256 ## Some state hash (if any)
serial*: uint64 ## Generic identifier from application
LayerDeltaRef* = ref object
## Delta layers are stacked implying a tables hierarchy. Table entries on
## a higher level take precedence over lower layer table entries. So an
## existing key-value table entry of a layer on top supersedes same key
## entries on all lower layers. A missing entry on a higher layer indicates
## that the key-value pair might be fond on some lower layer.
##
## A zero value (`nil`, empty hash etc.) is considered am missing key-value
## pair. Tables on the `LayerDelta` may have stray zero key-value pairs for
## missing entries due to repeated transactions while adding and deleting
## entries. There is no need to purge redundant zero entries.
##
## As for `kMap[]` entries, there might be a zero value entriy relating
## (i.e. indexed by the same vertex ID) to an `sMap[]` non-zero value entry
## (of the same layer or a lower layer whatever comes first.) This entry
## is kept as a reminder that the hash value of the `kMap[]` entry needs
## to be re-compiled.
##
## The reasoning behind the above scenario is that every vertex held on the
## `sTab[]` tables must correspond to a hash entry held on the `kMap[]`
## tables. So a corresponding zero value or missing entry produces an
## inconsistent state that must be resolved.
##
sTab*: Table[VertexID,VertexRef] ## Structural vertex table
kMap*: Table[VertexID,HashKey] ## Merkle hash key mapping
vTop*: VertexID ## Last used vertex ID
accSids*: Table[Hash256, VertexID] ## Account path -> stoID
LayerRef* = ref LayerObj
LayerObj* = object
## Hexary trie database layer structures. Any layer holds the full
## change relative to the backend.
delta*: LayerDeltaRef ## Most structural tables held as deltas
txUid*: uint ## Transaction identifier if positive
# ------------------------------------------------------------------------------
# Public helpers (misc)
# ------------------------------------------------------------------------------
func init*(T: type LayerRef): T =
## Constructor, returns empty layer
T(delta: LayerDeltaRef())
func hash*(node: NodeRef): Hash =
## Table/KeyedQueue/HashSet mixin
cast[pointer](node).hash
# ------------------------------------------------------------------------------
# Public helpers: `NodeRef` and `PayloadRef`
# ------------------------------------------------------------------------------
proc `==`*(a, b: PayloadRef): bool =
## Beware, potential deep comparison
if a.isNil:
return b.isNil
if b.isNil:
return false
if unsafeAddr(a) != unsafeAddr(b):
if a.pType != b.pType:
return false
case a.pType:
of RawData:
if a.rawBlob != b.rawBlob:
return false
of AccountData:
if a.account != b.account or
a.stoID != b.stoID:
return false
true
proc `==`*(a, b: VertexRef): bool =
## Beware, potential deep comparison
if a.isNil:
return b.isNil
if b.isNil:
return false
if unsafeAddr(a[]) != unsafeAddr(b[]):
if a.vType != b.vType:
return false
case a.vType:
of Leaf:
if a.lPfx != b.lPfx or a.lData != b.lData:
return false
of Extension:
if a.ePfx != b.ePfx or a.eVid != b.eVid:
return false
of Branch:
for n in 0..15:
if a.bVid[n] != b.bVid[n]:
return false
true
proc `==`*(a, b: NodeRef): bool =
## Beware, potential deep comparison
if a.VertexRef != b.VertexRef:
return false
case a.vType:
of Extension:
if a.key[0] != b.key[0]:
return false
of Branch:
for n in 0..15:
if a.bVid[n] != 0.VertexID and a.key[n] != b.key[n]:
return false
else:
discard
true
# ------------------------------------------------------------------------------
# Public helpers, miscellaneous functions
# ------------------------------------------------------------------------------
func dup*(pld: PayloadRef): PayloadRef =
## Duplicate payload.
case pld.pType:
of RawData:
PayloadRef(
pType: RawData,
rawBlob: pld.rawBlob)
of AccountData:
PayloadRef(
pType: AccountData,
account: pld.account,
stoID: pld.stoID)
func dup*(vtx: VertexRef): VertexRef =
## Duplicate vertex.
# Not using `deepCopy()` here (some `gc` needs `--deepcopy:on`.)
if vtx.isNil:
VertexRef(nil)
else:
case vtx.vType:
of Leaf:
VertexRef(
vType: Leaf,
lPfx: vtx.lPfx,
lData: vtx.lData.dup)
of Extension:
VertexRef(
vType: Extension,
ePfx: vtx.ePfx,
eVid: vtx.eVid)
of Branch:
VertexRef(
vType: Branch,
bVid: vtx.bVid)
func dup*(node: NodeRef): NodeRef =
## Duplicate node.
# Not using `deepCopy()` here (some `gc` needs `--deepcopy:on`.)
if node.isNil:
NodeRef(nil)
else:
case node.vType:
of Leaf:
NodeRef(
vType: Leaf,
lPfx: node.lPfx,
lData: node.lData.dup,
key: node.key)
of Extension:
NodeRef(
vType: Extension,
ePfx: node.ePfx,
eVid: node.eVid,
key: node.key)
of Branch:
NodeRef(
vType: Branch,
bVid: node.bVid,
key: node.key)
func dup*(wp: VidVtxPair): VidVtxPair =
## Safe copy of `wp` argument
VidVtxPair(
vid: wp.vid,
vtx: wp.vtx.dup)
# ---------------
func to*(node: NodeRef; T: type VertexRef): T =
## Extract a copy of the `VertexRef` part from a `NodeRef`.
node.VertexRef.dup
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------