Documentation
¶
Overview ¶
Package trie implements Merkle Patricia Tries.
Index ¶
- Variables
- func CacheMisses() int64
- func CacheUnloads() int64
- func VerifyProof(rootHash common.Hash, key []byte, proofDb store.DatabaseReader) (value []byte, err error, nodes int)
- type Iterator
- type LeafCallback
- type MissingNodeError
- type NodeIterator
- type SecureTrie
- func (t *SecureTrie) Commit(onleaf LeafCallback) (root common.Hash, err error)
- func (t *SecureTrie) Copy() *SecureTrie
- func (t *SecureTrie) Delete(key []byte)
- func (t *SecureTrie) Get(key []byte) []byte
- func (t *SecureTrie) GetKey(shaKey []byte) []byte
- func (t *SecureTrie) Hash() common.Hash
- func (t *SecureTrie) NodeIterator(start []byte) NodeIterator
- func (t *SecureTrie) Root() []byte
- func (t *SecureTrie) TryDelete(key []byte) error
- func (t *SecureTrie) TryGet(key []byte) ([]byte, error)
- func (t *SecureTrie) TryUpdate(key, value []byte) error
- func (t *SecureTrie) Update(key, value []byte)
- type SyncResult
- type Trie
- func (t *Trie) Commit(onleaf LeafCallback) (root common.Hash, err error)
- func (t *Trie) Delete(key []byte)
- func (t *Trie) Get(key []byte) []byte
- func (t *Trie) Hash() common.Hash
- func (t *Trie) NodeIterator(start []byte) NodeIterator
- func (t *Trie) Root() []byte
- func (t *Trie) SetCacheLimit(l uint16)
- func (t *Trie) TryDelete(key []byte) error
- func (t *Trie) TryGet(key []byte) ([]byte, error)
- func (t *Trie) TryUpdate(key, value []byte) error
- func (t *Trie) Update(key, value []byte)
- type TrieSync
- func (s *TrieSync) AddRawEntry(hash common.Hash, depth int, parent common.Hash)
- func (s *TrieSync) AddSubTrie(root common.Hash, depth int, parent common.Hash, callback LeafCallback)
- func (s *TrieSync) Missing(max int) []common.Hash
- func (s *TrieSync) Pending() int
- func (s *TrieSync) Process(results []SyncResult) (bool, int, error)
Constants ¶
This section is empty.
Variables ¶
var ErrAlreadyProcessed = errors.New("already processed")
ErrAlreadyProcessed is returned by the trie sync when it's requested to process a node it already processed previously.
var ErrNotRequested = errors.New("not requested")
ErrNotRequested is returned by the trie sync when it's requested to process a node it did not request.
Functions ¶
func CacheMisses ¶
func CacheMisses() int64
CacheMisses retrieves a global counter measuring the number of cache misses the trie had since process startup. This isn't useful for anything apart from trie debugging purposes.
func CacheUnloads ¶
func CacheUnloads() int64
CacheUnloads retrieves a global counter measuring the number of cache unloads the trie did since process startup. This isn't useful for anything apart from trie debugging purposes.
func VerifyProof ¶
func VerifyProof(rootHash common.Hash, key []byte, proofDb store.DatabaseReader) (value []byte, err error, nodes int)
VerifyProof checks merkle proofs. The given proof must contain the value for key in a trie with the given root hash. VerifyProof returns an error if the proof contains invalid trie nodes or the wrong value.
Types ¶
type Iterator ¶
type Iterator struct {
Key []byte // Current data key on which the iterator is positioned on
Value []byte // Current data value on which the iterator is positioned on
Err error
// contains filtered or unexported fields
}
Iterator is a key-value trie iterator that traverses a Trie.
func NewIterator ¶
func NewIterator(it NodeIterator) *Iterator
NewIterator creates a new key-value iterator from a node iterator
type LeafCallback ¶
LeafCallback is a callback type invoked when a trie operation reaches a leaf node. It's used by state sync and commit to allow handling external references between account and storage tries.
type MissingNodeError ¶
type MissingNodeError struct {
NodeHash common.Hash // hash of the missing node
Path []byte // hex-encoded path to the missing node
}
func (*MissingNodeError) Error ¶
func (err *MissingNodeError) Error() string
type NodeIterator ¶
type NodeIterator interface {
// Next moves the iterator to the next node. If the parameter is false, any child
// nodes will be skipped.
Next(bool) bool
// Error returns the error status of the iterator.
Error() error
// Hash returns the hash of the current node.
Hash() common.Hash
// Parent returns the hash of the parent of the current node. The hash may be the one
// grandparent if the immediate parent is an internal node with no hash.
Parent() common.Hash
// Path returns the hex-encoded path to the current node.
// Callers must not retain references to the return value after calling Next.
// For leaf nodes, the last element of the path is the 'terminator symbol' 0x10.
Path() []byte
// Leaf returns true iff the current node is a leaf node.
// LeafBlob, LeafKey return the contents and key of the leaf node. These
// method panic if the iterator is not positioned at a leaf.
// Callers must not retain references to their return value after calling Next
Leaf() bool
LeafBlob() []byte
LeafKey() []byte
}
NodeIterator is an iterator to traverse the trie pre-order.
func NewDifferenceIterator ¶
func NewDifferenceIterator(a, b NodeIterator) (NodeIterator, *int)
NewDifferenceIterator constructs a NodeIterator that iterates over elements in b that are not in a. Returns the iterator, and a pointer to an integer recording the number of nodes seen.
func NewUnionIterator ¶
func NewUnionIterator(iters []NodeIterator) (NodeIterator, *int)
NewUnionIterator constructs a NodeIterator that iterates over elements in the union of the provided NodeIterators. Returns the iterator, and a pointer to an integer recording the number of nodes visited.
type SecureTrie ¶
type SecureTrie struct {
// contains filtered or unexported fields
}
SecureTrie wraps a trie with key hashing. In a secure trie, all access operations hash the key using keccak256. This prevents calling code from creating long chains of nodes that increase the access time.
Contrary to a regular trie, a SecureTrie can only be created with New and must have an attached database. The database also stores the preimage of each key.
SecureTrie is not safe for concurrent use.
func NewSecure ¶
func NewSecure(root common.Hash, db *store.TrieDatabase, cachelimit uint16) (*SecureTrie, error)
NewSecure creates a trie with an existing root node from a backing database and optional intermediate in-memory node pool.
If root is the zero hash or the sha3 hash of an empty string, the trie is initially empty. Otherwise, New will panic if db is nil and returns MissingNodeError if the root node cannot be found.
Accessing the trie loads nodes from the database or node pool on demand. Loaded nodes are kept around until their 'cache generation' expires. A new cache generation is created by each call to Commit. cachelimit sets the number of past cache generations to keep.
func (*SecureTrie) Commit ¶
func (t *SecureTrie) Commit(onleaf LeafCallback) (root common.Hash, err error)
Commit writes all nodes and the secure hash pre-images to the trie's database. Nodes are stored with their sha3 hash as the key.
Committing flushes nodes from memory. Subsequent Get calls will load nodes from the database.
func (*SecureTrie) Copy ¶
func (t *SecureTrie) Copy() *SecureTrie
func (*SecureTrie) Delete ¶
func (t *SecureTrie) Delete(key []byte)
Delete removes any existing value for key from the trie.
func (*SecureTrie) Get ¶
func (t *SecureTrie) Get(key []byte) []byte
Get returns the value for key stored in the trie. The value bytes must not be modified by the caller.
func (*SecureTrie) GetKey ¶
func (t *SecureTrie) GetKey(shaKey []byte) []byte
GetKey returns the sha3 preimage of a hashed key that was previously used to store a value.
func (*SecureTrie) Hash ¶
func (t *SecureTrie) Hash() common.Hash
func (*SecureTrie) NodeIterator ¶
func (t *SecureTrie) NodeIterator(start []byte) NodeIterator
NodeIterator returns an iterator that returns nodes of the underlying trie. Iteration starts at the key after the given start key.
func (*SecureTrie) Root ¶
func (t *SecureTrie) Root() []byte
func (*SecureTrie) TryDelete ¶
func (t *SecureTrie) TryDelete(key []byte) error
TryDelete removes any existing value for key from the trie. If a node was not found in the database, a MissingNodeError is returned.
func (*SecureTrie) TryGet ¶
func (t *SecureTrie) TryGet(key []byte) ([]byte, error)
TryGet returns the value for key stored in the trie. The value bytes must not be modified by the caller. If a node was not found in the database, a MissingNodeError is returned.
func (*SecureTrie) TryUpdate ¶
func (t *SecureTrie) TryUpdate(key, value []byte) error
TryUpdate associates key with value in the trie. Subsequent calls to Get will return value. If value has length zero, any existing value is deleted from the trie and calls to Get will return nil.
The value bytes must not be modified by the caller while they are stored in the trie.
If a node was not found in the database, a MissingNodeError is returned.
func (*SecureTrie) Update ¶
func (t *SecureTrie) Update(key, value []byte)
Update associates key with value in the trie. Subsequent calls to Get will return value. If value has length zero, any existing value is deleted from the trie and calls to Get will return nil.
The value bytes must not be modified by the caller while they are stored in the trie.
type SyncResult ¶
type SyncResult struct {
Hash common.Hash // Hash of the originally unknown trie node
Data []byte // Data content of the retrieved node
}
SyncResult is a simple list to return missing nodes along with their request hashes.
type Trie ¶
type Trie struct {
// contains filtered or unexported fields
}
Trie is a Merkle Patricia Trie. The zero value is an empty trie with no database. Use New to create a trie that sits on top of a database.
Trie is not safe for concurrent use.
func New ¶
New creates a trie with an existing root node from db.
If root is the zero hash or the sha3 hash of an empty string, the trie is initially empty and does not require a database. Otherwise, New will panic if db is nil and returns a MissingNodeError if root does not exist in the database. Accessing the trie loads nodes from db on demand.
func (*Trie) Commit ¶
func (t *Trie) Commit(onleaf LeafCallback) (root common.Hash, err error)
Commit writes all nodes to the trie's memory database, tracking the internal and external (for account tries) references.
func (*Trie) Get ¶
Get returns the value for key stored in the trie. The value bytes must not be modified by the caller.
func (*Trie) Hash ¶
Hash returns the root hash of the trie. It does not write to the database and can be used even if the trie doesn't have one.
func (*Trie) NodeIterator ¶
func (t *Trie) NodeIterator(start []byte) NodeIterator
NodeIterator returns an iterator that returns nodes of the trie. Iteration starts at the key after the given start key.
func (*Trie) SetCacheLimit ¶
SetCacheLimit sets the number of 'cache generations' to keep. A cache generation is created by a call to Commit.
func (*Trie) TryDelete ¶
TryDelete removes any existing value for key from the trie. If a node was not found in the database, a MissingNodeError is returned.
func (*Trie) TryGet ¶
TryGet returns the value for key stored in the trie. The value bytes must not be modified by the caller. If a node was not found in the database, a MissingNodeError is returned.
func (*Trie) TryUpdate ¶
TryUpdate associates key with value in the trie. Subsequent calls to Get will return value. If value has length zero, any existing value is deleted from the trie and calls to Get will return nil.
The value bytes must not be modified by the caller while they are stored in the trie.
If a node was not found in the database, a MissingNodeError is returned.
func (*Trie) Update ¶
Update associates key with value in the trie. Subsequent calls to Get will return value. If value has length zero, any existing value is deleted from the trie and calls to Get will return nil.
The value bytes must not be modified by the caller while they are stored in the trie.
type TrieSync ¶
type TrieSync struct {
// contains filtered or unexported fields
}
TrieSync is the main state trie synchronisation scheduler, which provides yet unknown trie hashes to retrieve, accepts node data associated with said hashes and reconstructs the trie step by step until all is done.
func NewTrieSync ¶
func NewTrieSync(root common.Hash, database store.DatabaseReader, callback LeafCallback) *TrieSync
NewTrieSync creates a new trie data download scheduler.
func (*TrieSync) AddRawEntry ¶
AddRawEntry schedules the direct retrieval of a state entry that should not be interpreted as a trie node, but rather accepted and stored into the database as is. This method's goal is to support misc state metadata retrievals (e.g. contract code).
func (*TrieSync) AddSubTrie ¶
func (s *TrieSync) AddSubTrie(root common.Hash, depth int, parent common.Hash, callback LeafCallback)
AddSubTrie registers a new trie to the sync code, rooted at the designated parent.
Source Files