735 lines
23 KiB
Nim
735 lines
23 KiB
Nim
# nimbus-eth1
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# Copyright (c) 2021 Status Research & Development GmbH
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# Licensed under either of
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# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
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# http://www.apache.org/licenses/LICENSE-2.0)
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# * MIT license ([LICENSE-MIT](LICENSE-MIT) or
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# http://opensource.org/licenses/MIT)
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# at your option. This file may not be copied, modified, or distributed
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# except according to those terms.
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import
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std/tables,
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eth/[common, trie/nibbles],
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stew/results,
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../../range_desc,
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"."/[hexary_desc, hexary_error, hexary_paths]
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{.push raises: [Defect].}
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proc hexaryNearbyRight*(path: RPath; db: HexaryTreeDbRef;
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): Result[RPath,HexaryError] {.gcsafe, raises: [Defect,KeyError]}
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proc hexaryNearbyRight*(path: XPath; getFn: HexaryGetFn;
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): Result[XPath,HexaryError] {.gcsafe, raises: [Defect,RlpError]}
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# ------------------------------------------------------------------------------
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# Private helpers
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# ------------------------------------------------------------------------------
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proc toBranchNode(
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rlp: Rlp
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): XNodeObj
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{.gcsafe, raises: [Defect,RlpError]} =
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var rlp = rlp
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XNodeObj(kind: Branch, bLink: rlp.read(array[17,Blob]))
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proc toLeafNode(
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rlp: Rlp;
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pSegm: NibblesSeq
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): XNodeObj
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{.gcsafe, raises: [Defect,RlpError]} =
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XNodeObj(kind: Leaf, lPfx: pSegm, lData: rlp.listElem(1).toBytes)
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proc toExtensionNode(
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rlp: Rlp;
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pSegm: NibblesSeq
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): XNodeObj
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{.gcsafe, raises: [Defect,RlpError]} =
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XNodeObj(kind: Extension, ePfx: pSegm, eLink: rlp.listElem(1).toBytes)
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proc `<=`(a, b: NibblesSeq): bool =
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## Compare nibbles, different lengths are padded to the right with zeros
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let abMin = min(a.len, b.len)
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for n in 0 ..< abMin:
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if a[n] < b[n]:
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return true
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if b[n] < a[n]:
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return false
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# otherwise a[n] == b[n]
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# Assuming zero for missing entries
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if b.len < a.len:
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for n in abMin + 1 ..< a.len:
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if 0 < a[n]:
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return false
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true
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proc `<`(a, b: NibblesSeq): bool =
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not (b <= a)
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template noKeyErrorOops(info: static[string]; code: untyped) =
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try:
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code
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except KeyError as e:
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raiseAssert "Impossible KeyError (" & info & "): " & e.msg
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template noRlpErrorOops(info: static[string]; code: untyped) =
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try:
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code
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except RlpError as e:
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raiseAssert "Impossible RlpError (" & info & "): " & e.msg
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# ------------------------------------------------------------------------------
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# Private functions, wrappers
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# ------------------------------------------------------------------------------
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proc hexaryNearbyRightImpl(
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baseTag: NodeTag; ## Some node
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rootKey: NodeKey; ## State root
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db: HexaryTreeDbRef|HexaryGetFn; ## Database abstraction
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): Result[NodeTag,HexaryError]
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{.gcsafe, raises: [Defect,KeyError,RlpError]} =
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## Wrapper
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let path = block:
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let rc = baseTag.hexaryPath(rootKey, db).hexaryNearbyRight(db)
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if rc.isErr:
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return err(rc.error)
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rc.value
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if 0 < path.path.len and path.path[^1].node.kind == Leaf:
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let nibbles = path.getNibbles
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if nibbles.len == 64:
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return ok(nibbles.getBytes.convertTo(NodeTag))
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err(NearbyLeafExpected)
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proc hexaryNearbyLeftImpl(
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baseTag: NodeTag; ## Some node
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rootKey: NodeKey; ## State root
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db: HexaryTreeDbRef|HexaryGetFn; ## Database abstraction
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): Result[NodeTag,HexaryError]
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{.gcsafe, raises: [Defect,KeyError,RlpError]} =
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## Wrapper
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let path = block:
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let rc = baseTag.hexaryPath(rootKey, db).hexaryNearbyLeft(db)
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if rc.isErr:
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return err(rc.error)
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rc.value
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if 0 < path.path.len and path.path[^1].node.kind == Leaf:
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let nibbles = path.getNibbles
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if nibbles.len == 64:
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return ok(nibbles.getBytes.convertTo(NodeTag))
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err(NearbyLeafExpected)
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# ------------------------------------------------------------------------------
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# Private functions
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# ------------------------------------------------------------------------------
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proc completeLeast(
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path: RPath;
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key: RepairKey;
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db: HexaryTreeDbRef;
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pathLenMax = 64;
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): Result[RPath,HexaryError]
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{.gcsafe, raises: [Defect,KeyError].} =
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## Extend path using least nodes without recursion.
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var rPath = RPath(path: path.path)
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if not db.tab.hasKey(key):
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return err(NearbyDanglingLink)
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var
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key = key
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node = db.tab[key]
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while rPath.path.len < pathLenMax:
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case node.kind:
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of Leaf:
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rPath.path.add RPathStep(key: key, node: node, nibble: -1)
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return ok(rPath) # done
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of Extension:
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block useExtensionLink:
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let newKey = node.eLink
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if not newkey.isZero:
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if db.tab.hasKey(newKey):
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rPath.path.add RPathStep(key: key, node: node, nibble: -1)
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key = newKey
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node = db.tab[key]
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break useExtensionLink
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return err(NearbyExtensionError) # Oops, no way
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of Branch:
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block findBranchLink:
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for inx in 0 .. 15:
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let newKey = node.bLink[inx]
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if not newKey.isZero:
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if db.tab.hasKey(newKey):
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rPath.path.add RPathStep(key: key, node: node, nibble: inx.int8)
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key = newKey
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node = db.tab[key]
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break findBranchLink
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return err(NearbyBranchError) # Oops, no way
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err(NearbyNestingTooDeep)
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proc completeLeast(
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path: XPath;
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key: Blob;
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getFn: HexaryGetFn;
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pathLenMax = 64;
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): Result[XPath,HexaryError]
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{.gcsafe, raises: [Defect,RlpError].} =
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## Variant of `completeLeast()` for persistent database
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var xPath = XPath(path: path.path)
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if key.getFn().len == 0:
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return err(NearbyDanglingLink)
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var
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key = key
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nodeRlp = rlpFromBytes key.getFn()
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while xPath.path.len < pathLenMax:
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case nodeRlp.listLen:
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of 2:
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let (isLeaf,pathSegment) = hexPrefixDecode nodeRlp.listElem(0).toBytes
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if isLeaf:
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let node = nodeRlp.toLeafNode(pathSegment)
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xPath.path.add XPathStep(key: key, node: node, nibble: -1)
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return ok(xPath) # done
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# Extension
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block useExtensionLink:
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let
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node = nodeRlp.toExtensionNode(pathSegment)
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newKey = node.eLink
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if 0 < newKey.len:
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let newNode = newKey.getFn()
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if 0 < newNode.len:
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xPath.path.add XPathStep(key: key, node: node, nibble: -1)
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key = newKey
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nodeRlp = rlpFromBytes newNode
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break useExtensionLink
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return err(NearbyExtensionError) # Oops, no way
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of 17:
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block findBranchLink:
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let node = nodeRlp.toBranchNode()
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for inx in 0 .. 15:
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let newKey = node.bLink[inx]
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if 0 < newKey.len:
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let newNode = newKey.getFn()
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if 0 < newNode.len:
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xPath.path.add XPathStep(key: key, node: node, nibble: inx.int8)
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key = newKey
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nodeRlp = rlpFromBytes newNode
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break findBranchLink
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return err(NearbyBranchError) # Oops, no way
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else:
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return err(NearbyGarbledNode) # Oops, no way
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err(NearbyNestingTooDeep)
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proc completeMost(
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path: RPath;
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key: RepairKey;
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db: HexaryTreeDbRef;
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pathLenMax = 64;
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): Result[RPath,HexaryError]
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{.gcsafe, raises: [Defect,KeyError].} =
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## Extend path using max nodes without recursion.
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var rPath = RPath(path: path.path)
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if not db.tab.hasKey(key):
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return err(NearbyDanglingLink)
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var
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key = key
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node = db.tab[key]
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while rPath.path.len < pathLenMax:
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case node.kind:
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of Leaf:
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rPath.path.add RPathStep(key: key, node: node, nibble: -1)
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return ok(rPath) # done
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of Extension:
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block useExtensionLink:
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let newKey = node.eLink
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if not newkey.isZero:
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if db.tab.hasKey(newKey):
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rPath.path.add RPathStep(key: key, node: node, nibble: -1)
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key = newKey
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node = db.tab[newKey]
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break useExtensionLink
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return err(NearbyExtensionError) # Oops, no way
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of Branch:
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block findBranchLink:
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for inx in 15.countDown(0):
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let newKey = node.bLink[inx]
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if not newKey.isZero:
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if db.tab.hasKey(newKey):
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rPath.path.add RPathStep(key: key, node: node, nibble: inx.int8)
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key = newKey
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node = db.tab[key]
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break findBranchLink
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return err(NearbyBranchError) # Oops, no way
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err(NearbyNestingTooDeep)
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proc completeMost(
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path: XPath;
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key: Blob;
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getFn: HexaryGetFn;
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pathLenMax = 64;
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): Result[XPath,HexaryError]
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{.gcsafe, raises: [Defect,RlpError].} =
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## Variant of `completeLeast()` for persistent database
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var xPath = XPath(path: path.path)
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if key.getFn().len == 0:
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return err(NearbyDanglingLink)
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var
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key = key
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nodeRlp = rlpFromBytes key.getFn()
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while xPath.path.len < pathLenMax:
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case nodeRlp.listLen:
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of 2:
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let (isLeaf,pathSegment) = hexPrefixDecode nodeRlp.listElem(0).toBytes
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if isLeaf:
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let node = nodeRlp.toLeafNode(pathSegment)
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xPath.path.add XPathStep(key: key, node: node, nibble: -1)
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return ok(xPath) # done
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# Extension
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block useExtensionLink:
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let
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node = nodeRlp.toExtensionNode(pathSegment)
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newKey = node.eLink
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if 0 < newKey.len:
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let newNode = newKey.getFn()
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if 0 < newNode.len:
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xPath.path.add XPathStep(key: key, node: node, nibble: -1)
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key = newKey
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nodeRlp = rlpFromBytes newNode
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break useExtensionLink
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return err(NearbyExtensionError) # Oops, no way
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of 17:
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block findBranchLink:
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let node = nodeRlp.toBranchNode()
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for inx in 15.countDown(0):
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let newKey = node.bLink[inx]
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if 0 < newKey.len:
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let newNode = newKey.getFn()
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if 0 < newNode.len:
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xPath.path.add XPathStep(key: key, node: node, nibble: inx.int8)
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key = newKey
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nodeRlp = rlpFromBytes newNode
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break findBranchLink
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return err(NearbyBranchError) # Oops, no way
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else:
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return err(NearbyGarbledNode) # Oops, no way
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err(NearbyNestingTooDeep)
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# ------------------------------------------------------------------------------
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# Public functions, left boundary proofs (moving right)
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# ------------------------------------------------------------------------------
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proc hexaryNearbyRight*(
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path: RPath; ## Partially expanded path
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db: HexaryTreeDbRef; ## Database
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): Result[RPath,HexaryError]
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{.gcsafe, raises: [Defect,KeyError]} =
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## Extends the maximally extended argument nodes `path` to the right (i.e.
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## with non-decreasing path value). This is similar to the
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## `hexary_path.next()` function, only that this algorithm does not
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## backtrack if there are dangling links in between and rather returns
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## a error.
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##
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## This code is intended be used for verifying a left-bound proof to verify
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## that there is no leaf node.
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# Some easy cases
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if path.path.len == 0:
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return err(NearbyEmptyPath) # error
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if path.path[^1].node.kind == Leaf:
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return ok(path)
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var rPath = path
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while 0 < rPath.path.len:
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let top = rPath.path[^1]
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if top.node.kind != Branch or
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top.nibble < 0 or
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rPath.tail.len == 0:
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return err(NearbyUnexpectedNode) # error
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let topLink = top.node.bLink[top.nibble]
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if topLink.isZero or not db.tab.hasKey(topLink):
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return err(NearbyDanglingLink) # error
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let nextNibble = rPath.tail[0].int8
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if nextNibble < 15:
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let
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nextNode = db.tab[topLink]
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rPathLen = rPath.path.len # in case of backtracking
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rPathTail = rPath.tail
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case nextNode.kind
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of Leaf:
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if rPath.tail <= nextNode.lPfx:
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return rPath.completeLeast(topLink, db)
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of Extension:
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if rPath.tail <= nextNode.ePfx:
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return rPath.completeLeast(topLink, db)
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of Branch:
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# Step down and complete with a branch link on the child node
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rPath.path = rPath.path & RPathStep(
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key: topLink,
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node: nextNode,
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nibble: nextNibble)
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# Find the next item to the right of the new top entry
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let step = rPath.path[^1]
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for inx in (step.nibble + 1) .. 15:
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let link = step.node.bLink[inx]
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if not link.isZero:
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rPath.path[^1].nibble = inx.int8
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return rPath.completeLeast(link, db)
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# Restore `rPath` and backtrack
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rPath.path.setLen(rPathLen)
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rPath.tail = rPathTail
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# Pop `Branch` node on top and append nibble to `tail`
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rPath.tail = @[top.nibble.byte].initNibbleRange.slice(1) & rPath.tail
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rPath.path.setLen(rPath.path.len - 1)
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# Pathological case: nfffff.. for n < f
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var step = path.path[0]
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for inx in (step.nibble + 1) .. 15:
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let link = step.node.bLink[inx]
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if not link.isZero:
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step.nibble = inx.int8
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rPath.path = @[step]
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return rPath.completeLeast(link, db)
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err(NearbyFailed) # error
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proc hexaryNearbyRight*(
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path: XPath; ## Partially expanded path
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getFn: HexaryGetFn; ## Database abstraction
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): Result[XPath,HexaryError]
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{.gcsafe, raises: [Defect,RlpError]} =
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## Variant of `hexaryNearbyRight()` for persistant database
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# Some easy cases
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if path.path.len == 0:
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return err(NearbyEmptyPath) # error
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if path.path[^1].node.kind == Leaf:
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return ok(path)
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var xPath = path
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while 0 < xPath.path.len:
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let top = xPath.path[^1]
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if top.node.kind != Branch or
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top.nibble < 0 or
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xPath.tail.len == 0:
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return err(NearbyUnexpectedNode) # error
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let topLink = top.node.bLink[top.nibble]
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if topLink.len == 0 or topLink.getFn().len == 0:
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return err(NearbyDanglingLink) # error
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let nextNibble = xPath.tail[0].int8
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if nextNibble < 15:
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let
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nextNodeRlp = rlpFromBytes topLink.getFn()
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xPathLen = xPath.path.len # in case of backtracking
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xPathTail = xPath.tail
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case nextNodeRlp.listLen:
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of 2:
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if xPath.tail <= nextNodeRlp.listElem(0).toBytes.hexPrefixDecode[1]:
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return xPath.completeLeast(topLink, getFn)
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of 17:
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# Step down and complete with a branch link on the child node
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xPath.path = xPath.path & XPathStep(
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key: topLink,
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node: nextNodeRlp.toBranchNode,
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nibble: nextNibble)
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else:
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return err(NearbyGarbledNode) # error
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# Find the next item to the right of the new top entry
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let step = xPath.path[^1]
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for inx in (step.nibble + 1) .. 15:
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let link = step.node.bLink[inx]
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if 0 < link.len:
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xPath.path[^1].nibble = inx.int8
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return xPath.completeLeast(link, getFn)
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# Restore `xPath` and backtrack
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xPath.path.setLen(xPathLen)
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xPath.tail = xPathTail
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# Pop `Branch` node on top and append nibble to `tail`
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xPath.tail = @[top.nibble.byte].initNibbleRange.slice(1) & xPath.tail
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xPath.path.setLen(xPath.path.len - 1)
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# Pathological case: nfffff.. for n < f
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var step = path.path[0]
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for inx in (step.nibble + 1) .. 15:
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let link = step.node.bLink[inx]
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if 0 < link.len:
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step.nibble = inx.int8
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xPath.path = @[step]
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return xPath.completeLeast(link, getFn)
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err(NearbyFailed) # error
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proc hexaryNearbyRightMissing*(
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path: RPath;
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db: HexaryTreeDbRef;
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): bool
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{.gcsafe, raises: [Defect,KeyError]} =
|
|
## Returns `true` if the maximally extended argument nodes `path` is the
|
|
## rightmost on the hexary trie database. It verifies that there is no more
|
|
## leaf entry to the right of the argument `path`.
|
|
##
|
|
## This code is intended be used for verifying a left-bound proof.
|
|
if 0 < path.path.len and 0 < path.tail.len:
|
|
let top = path.path[^1]
|
|
if top.node.kind == Branch and 0 <= top.nibble:
|
|
|
|
let topLink = top.node.bLink[top.nibble]
|
|
if not topLink.isZero and db.tab.hasKey(topLink):
|
|
let
|
|
nextNibble = path.tail[0]
|
|
nextNode = db.tab[topLink]
|
|
|
|
case nextNode.kind
|
|
of Leaf:
|
|
return nextNode.lPfx < path.tail
|
|
|
|
of Extension:
|
|
return nextNode.ePfx < path.tail
|
|
|
|
of Branch:
|
|
# Step down and verify that there is no branch link
|
|
for inx in nextNibble .. 15:
|
|
if not nextNode.bLink[inx].isZero:
|
|
return false
|
|
return true
|
|
|
|
# ------------------------------------------------------------------------------
|
|
# Public functions, right boundary proofs (moving left)
|
|
# ------------------------------------------------------------------------------
|
|
|
|
proc hexaryNearbyLeft*(
|
|
path: RPath; ## Partially expanded path
|
|
db: HexaryTreeDbRef; ## Database
|
|
): Result[RPath,HexaryError]
|
|
{.gcsafe, raises: [Defect,KeyError]} =
|
|
## Similar to `hexaryNearbyRight()`.
|
|
##
|
|
## This code is intended be used for verifying a right-bound proof to verify
|
|
## that there is no leaf node.
|
|
|
|
# Some easy cases
|
|
if path.path.len == 0:
|
|
return err(NearbyEmptyPath) # error
|
|
if path.path[^1].node.kind == Leaf:
|
|
return ok(path)
|
|
|
|
var rPath = path
|
|
while 0 < rPath.path.len:
|
|
let top = rPath.path[^1]
|
|
if top.node.kind != Branch or
|
|
top.nibble < 0 or
|
|
rPath.tail.len == 0:
|
|
return err(NearbyUnexpectedNode) # error
|
|
|
|
let topLink = top.node.bLink[top.nibble]
|
|
if topLink.isZero or not db.tab.hasKey(topLink):
|
|
return err(NearbyDanglingLink) # error
|
|
|
|
let nextNibble = rPath.tail[0].int8
|
|
if 0 < nextNibble:
|
|
let
|
|
nextNode = db.tab[topLink]
|
|
rPathLen = rPath.path.len # in case of backtracking
|
|
rPathTail = rPath.tail
|
|
case nextNode.kind
|
|
of Leaf:
|
|
if nextNode.lPfx <= rPath.tail:
|
|
return rPath.completeMost(topLink, db)
|
|
of Extension:
|
|
if nextNode.ePfx <= rPath.tail:
|
|
return rPath.completeMost(topLink, db)
|
|
of Branch:
|
|
# Step down and complete with a branch link on the child node
|
|
rPath.path = rPath.path & RPathStep(
|
|
key: topLink,
|
|
node: nextNode,
|
|
nibble: nextNibble)
|
|
|
|
# Find the next item to the right of the new top entry
|
|
let step = rPath.path[^1]
|
|
for inx in (step.nibble - 1).countDown(0):
|
|
let link = step.node.bLink[inx]
|
|
if not link.isZero:
|
|
rPath.path[^1].nibble = inx.int8
|
|
return rPath.completeMost(link, db)
|
|
|
|
# Restore `rPath` and backtrack
|
|
rPath.path.setLen(rPathLen)
|
|
rPath.tail = rPathTail
|
|
|
|
# Pop `Branch` node on top and append nibble to `tail`
|
|
rPath.tail = @[top.nibble.byte].initNibbleRange.slice(1) & rPath.tail
|
|
rPath.path.setLen(rPath.path.len - 1)
|
|
|
|
# Pathological case: n0000.. for 0 < n
|
|
var step = path.path[0]
|
|
for inx in (step.nibble - 1).countDown(0):
|
|
let link = step.node.bLink[inx]
|
|
if not link.isZero:
|
|
step.nibble = inx.int8
|
|
rPath.path = @[step]
|
|
return rPath.completeMost(link, db)
|
|
|
|
err(NearbyFailed) # error
|
|
|
|
|
|
proc hexaryNearbyLeft*(
|
|
path: XPath; ## Partially expanded path
|
|
getFn: HexaryGetFn; ## Database abstraction
|
|
): Result[XPath,HexaryError]
|
|
{.gcsafe, raises: [Defect,RlpError]} =
|
|
## Variant of `hexaryNearbyLeft()` for persistant database
|
|
|
|
# Some easy cases
|
|
if path.path.len == 0:
|
|
return err(NearbyEmptyPath) # error
|
|
if path.path[^1].node.kind == Leaf:
|
|
return ok(path)
|
|
|
|
var xPath = path
|
|
while 0 < xPath.path.len:
|
|
let top = xPath.path[^1]
|
|
if top.node.kind != Branch or
|
|
top.nibble < 0 or
|
|
xPath.tail.len == 0:
|
|
return err(NearbyUnexpectedNode) # error
|
|
|
|
let topLink = top.node.bLink[top.nibble]
|
|
if topLink.len == 0 or topLink.getFn().len == 0:
|
|
return err(NearbyDanglingLink) # error
|
|
|
|
let nextNibble = xPath.tail[0].int8
|
|
if 0 < nextNibble:
|
|
let
|
|
nextNodeRlp = rlpFromBytes topLink.getFn()
|
|
xPathLen = xPath.path.len # in case of backtracking
|
|
xPathTail = xPath.tail
|
|
case nextNodeRlp.listLen:
|
|
of 2:
|
|
if nextNodeRlp.listElem(0).toBytes.hexPrefixDecode[1] <= xPath.tail:
|
|
return xPath.completeMost(topLink, getFn)
|
|
of 17:
|
|
# Step down and complete with a branch link on the child node
|
|
xPath.path = xPath.path & XPathStep(
|
|
key: topLink,
|
|
node: nextNodeRlp.toBranchNode,
|
|
nibble: nextNibble)
|
|
else:
|
|
return err(NearbyGarbledNode) # error
|
|
|
|
# Find the next item to the right of the new top entry
|
|
let step = xPath.path[^1]
|
|
for inx in (step.nibble - 1).countDown(0):
|
|
let link = step.node.bLink[inx]
|
|
if 0 < link.len:
|
|
xPath.path[^1].nibble = inx.int8
|
|
return xPath.completeMost(link, getFn)
|
|
|
|
# Restore `xPath` and backtrack
|
|
xPath.path.setLen(xPathLen)
|
|
xPath.tail = xPathTail
|
|
|
|
# Pop `Branch` node on top and append nibble to `tail`
|
|
xPath.tail = @[top.nibble.byte].initNibbleRange.slice(1) & xPath.tail
|
|
xPath.path.setLen(xPath.path.len - 1)
|
|
|
|
# Pathological case: n00000.. for 0 < n
|
|
var step = path.path[0]
|
|
for inx in (step.nibble - 1).countDown(0):
|
|
let link = step.node.bLink[inx]
|
|
if 0 < link.len:
|
|
step.nibble = inx.int8
|
|
xPath.path = @[step]
|
|
return xPath.completeMost(link, getFn)
|
|
|
|
err(NearbyFailed) # error
|
|
|
|
# ------------------------------------------------------------------------------
|
|
# Public functions, convenience wrappers
|
|
# ------------------------------------------------------------------------------
|
|
|
|
proc hexaryNearbyRight*(
|
|
baseTag: NodeTag; ## Some node
|
|
rootKey: NodeKey; ## State root
|
|
db: HexaryTreeDbRef; ## Database
|
|
): Result[NodeTag,HexaryError]
|
|
{.gcsafe, raises: [Defect,KeyError]} =
|
|
## Variant of `hexaryNearbyRight()` working with `NodeTag` arguments rather
|
|
## than `RPath()` ones.
|
|
noRlpErrorOops("hexaryNearbyRight"):
|
|
return baseTag.hexaryNearbyRightImpl(rootKey, db)
|
|
|
|
proc hexaryNearbyRight*(
|
|
baseTag: NodeTag; ## Some node
|
|
rootKey: NodeKey; ## State root
|
|
getFn: HexaryGetFn; ## Database abstraction
|
|
): Result[NodeTag,HexaryError]
|
|
{.gcsafe, raises: [Defect,RlpError]} =
|
|
## Variant of `hexaryNearbyRight()` for persistant database
|
|
noKeyErrorOops("hexaryNearbyRight"):
|
|
return baseTag.hexaryNearbyRightImpl(rootKey, getFn)
|
|
|
|
|
|
proc hexaryNearbyLeft*(
|
|
baseTag: NodeTag; ## Some node
|
|
rootKey: NodeKey; ## State root
|
|
db: HexaryTreeDbRef; ## Database
|
|
): Result[NodeTag,HexaryError]
|
|
{.gcsafe, raises: [Defect,KeyError]} =
|
|
## Similar to `hexaryNearbyRight()` for `NodeKey` arguments.
|
|
noRlpErrorOops("hexaryNearbyLeft"):
|
|
return baseTag.hexaryNearbyLeftImpl(rootKey, db)
|
|
|
|
proc hexaryNearbyLeft*(
|
|
baseTag: NodeTag; ## Some node
|
|
rootKey: NodeKey; ## State root
|
|
getFn: HexaryGetFn; ## Database abstraction
|
|
): Result[NodeTag,HexaryError]
|
|
{.gcsafe, raises: [Defect,RlpError]} =
|
|
## Variant of `hexaryNearbyLeft()` for persistant database
|
|
noKeyErrorOops("hexaryNearbyLeft"):
|
|
return baseTag.hexaryNearbyLeftImpl(rootKey, getFn)
|
|
|
|
# ------------------------------------------------------------------------------
|
|
# End
|
|
# ------------------------------------------------------------------------------
|