Documentation
¶
Overview ¶
Package trie implements Merkle Patricia Tries.
Index ¶
- Variables
- func GenPossibleShortNodePreimage(preimages map[common.Hash][]byte)
- type Database
- type Iterator
- type LeafCallback
- type MissingNodeError
- type NodeIterator
- type SecureTrie
- func (t *SecureTrie) Commit(onleaf LeafCallback) (common.Hash, int, error)
- func (t *SecureTrie) Copy() *SecureTrie
- func (t *SecureTrie) Delete(key []byte)
- func (t *SecureTrie) Get(key []byte) []byte
- func (t *SecureTrie) Hash() common.Hash
- func (t *SecureTrie) NodeIterator(start []byte) NodeIterator
- func (t *SecureTrie) TryDelete(key []byte) error
- func (t *SecureTrie) TryGet(key []byte) ([]byte, error)
- func (t *SecureTrie) TryGetNode(path []byte) ([]byte, int, error)
- func (t *SecureTrie) TryUpdate(key, value []byte) error
- func (t *SecureTrie) TryUpdateAccount(key []byte, acc *types.StateAccount) error
- func (t *SecureTrie) Update(key, value []byte)
- type StackTrie
- func (st *StackTrie) Commit() (h common.Hash, err error)
- func (st *StackTrie) Hash() (h common.Hash)
- func (st *StackTrie) MarshalBinary() (data []byte, err error)
- func (st *StackTrie) Reset()
- func (st *StackTrie) TryUpdate(key, value []byte) error
- func (st *StackTrie) UnmarshalBinary(data []byte) error
- func (st *StackTrie) Update(key, value []byte)
- type Trie
- func (t *Trie) Commit(onleaf LeafCallback) (common.Hash, int, error)
- func (t *Trie) Copy() *Trie
- 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) Reset()
- func (t *Trie) TryDelete(key []byte) error
- func (t *Trie) TryGet(key []byte) ([]byte, error)
- func (t *Trie) TryGetNode(path []byte) ([]byte, int, error)
- func (t *Trie) TryUpdate(key, value []byte) error
- func (t *Trie) TryUpdateAccount(key []byte, acc *types.StateAccount) error
- func (t *Trie) Update(key, value []byte)
Constants ¶
This section is empty.
Variables ¶
var ErrCommitDisabled = errors.New("no database for committing")
Functions ¶
Types ¶
type Database ¶
type Database struct {
BlockNumber *big.Int
Root common.Hash
// contains filtered or unexported fields
}
func NewDatabase ¶
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. Note that the value returned by the iterator is raw. If the content is encoded (e.g. storage value is RLP-encoded), it's caller's duty to decode it.
type LeafCallback ¶
LeafCallback is a callback type invoked when a trie operation reaches a leaf node.
The paths is a path tuple identifying a particular trie node either in a single trie (account) or a layered trie (account -> storage). Each path in the tuple is in the raw format(32 bytes).
The hexpath is a composite hexary path identifying the trie node. All the key bytes are converted to the hexary nibbles and composited with the parent path if the trie node is in a layered trie.
It's used by state sync and commit to allow handling external references between account and storage tries. And also it's used in the state healing for extracting the raw states(leaf nodes) with corresponding paths.
type MissingNodeError ¶
type MissingNodeError struct {
NodeHash common.Hash // hash of the missing node
Path []byte // hex-encoded path to the missing node
}
MissingNodeError is returned by the trie functions (TryGet, TryUpdate, TryDelete) in the case where a trie node is not present in the local database. It contains information necessary for retrieving 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
// NodeBlob returns the rlp-encoded value of the current iterated node.
// If the node is an embedded node in its parent, nil is returned then.
NodeBlob() []byte
// Leaf returns true iff the current node is a leaf node.
Leaf() bool
// LeafKey returns the key of the leaf. The method panics if the iterator is not
// positioned at a leaf. Callers must not retain references to the value after
// calling Next.
LeafKey() []byte
// LeafBlob returns the content of the leaf. The method panics if the iterator
// is not positioned at a leaf. Callers must not retain references to the value
// after calling Next.
LeafBlob() []byte
// LeafProof returns the Merkle proof of the leaf. The method panics if the
// iterator is not positioned at a leaf. Callers must not retain references
// to the value after calling Next.
LeafProof() [][]byte
// AddResolver sets an intermediate database to use for looking up trie nodes
// before reaching into the real persistent layer.
//
// This is not required for normal operation, rather is an optimization for
// cases where trie nodes can be recovered from some external mechanism without
// reading from disk. In those cases, this resolver allows short circuiting
// accesses and returning them from memory.
//
// Before adding a similar mechanism to any other place in Geth, consider
// making trie.Database an interface and wrapping at that level. It's a huge
// refactor, but it could be worth it if another occurrence arises.
AddResolver(ethdb.KeyValueReader)
}
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 *Database) (*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) (common.Hash, int, 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
Copy returns a copy of 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) Hash ¶
func (t *SecureTrie) Hash() common.Hash
Hash returns the root hash of SecureTrie. It does not write to the database and can be used even if the trie doesn't have one.
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) 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) TryGetNode ¶
func (t *SecureTrie) TryGetNode(path []byte) ([]byte, int, error)
TryGetNode attempts to retrieve a trie node by compact-encoded path. It is not possible to use keybyte-encoding as the path might contain odd nibbles.
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) TryUpdateAccount ¶
func (t *SecureTrie) TryUpdateAccount(key []byte, acc *types.StateAccount) error
TryUpdateAccount account will abstract the write of an account to the secure trie.
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 StackTrie ¶
type StackTrie struct {
// contains filtered or unexported fields
}
StackTrie is a trie implementation that expects keys to be inserted in order. Once it determines that a subtree will no longer be inserted into, it will hash it and free up the memory it uses.
func NewFromBinary ¶
func NewFromBinary(data []byte, db ethdb.KeyValueWriter) (*StackTrie, error)
NewFromBinary initialises a serialized stacktrie with the given db.
func NewStackTrie ¶
func NewStackTrie(db ethdb.KeyValueWriter) *StackTrie
NewStackTrie allocates and initializes an empty trie.
func (*StackTrie) Commit ¶
Commit will firstly hash the entrie trie if it's still not hashed and then commit all nodes to the associated database. Actually most of the trie nodes MAY have been committed already. The main purpose here is to commit the root node.
The associated database is expected, otherwise the whole commit functionality should be disabled.
func (*StackTrie) MarshalBinary ¶
MarshalBinary implements encoding.BinaryMarshaler
func (*StackTrie) UnmarshalBinary ¶
UnmarshalBinary implements encoding.BinaryUnmarshaler
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 ¶
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) Reset ¶
func (t *Trie) Reset()
Reset drops the referenced root node and cleans all internal state.
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) TryGetNode ¶
TryGetNode attempts to retrieve a trie node by compact-encoded path. It is not possible to use keybyte-encoding as the path might contain odd nibbles.
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) TryUpdateAccount ¶
func (t *Trie) TryUpdateAccount(key []byte, acc *types.StateAccount) error
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.
Source Files