This change makes the StateDB track the state key value diff of a block transition.
We already tracked current account and storage values for the purpose of updating
the state snapshot. With this PR, we now also track the original (pre-transition) values
of accounts and storage slots.
The state availability is checked during the creation of a state reader.
- In hash-based database, if the specified root node does not exist on disk disk, then
the state reader won't be created and an error will be returned.
- In path-based database, if the specified state layer is not available, then the
state reader won't be created and an error will be returned.
This change also contains a stricter semantics regarding the `Commit` operation: once it has been performed, the trie is no longer usable, and certain operations will return an error.
This change ports some changes from the main PBSS PR:
- get rid of callback function in `trie.Database.Commit` which is not required anymore
- rework the `nodeResolver` in `trie.Iterator` to make it compatible with multiple state scheme
- some other shallow changes in tests and typo-fixes
This change introduces garbage collection for the light client. Historical
chain data is deleted periodically. If you want to disable the GC, use
the --light.nopruning flag.
This finally adds the error check that the documentation of StateDB.dbErr
promises to do. dbErr was added in 9e5f03b6c (June 2017), and the check was
already missing in that commit. We somehow survived without it for three years.
With this commit, core/state's access to the underlying key/value database is
mediated through an interface. Database errors are tracked in StateDB and
returned by CommitTo or the new Error method.
Motivation for this change: We can remove the light client's duplicated copy of
core/state. The light client now supports node iteration, so tracing and storage
enumeration can work with the light client (not implemented in this commit).
In `touch` operation, only `touched` filed has been changed. Therefore
in the related undo function, only `touched` field should be reverted.
In addition, whether remove this obj from dirty map should depend on
prevDirty flag.
This significantly reduces the dependency closure of ethclient, which no
longer depends on core/vm as of this change.
All uses of vm.Logs are replaced by []*types.Log. NewLog is gone too,
the constructor simply returned a literal.
This commit implements EIP158 part 1, 2, 3 & 4
1. If an account is empty it's no longer written to the trie. An empty
account is defined as (balance=0, nonce=0, storage=0, code=0).
2. Delete an empty account if it's touched
3. An empty account is redefined as either non-existent or empty.
4. Zero value calls and zero value suicides no longer consume the 25k
reation costs.
params: moved core/config to params
Signed-off-by: Jeffrey Wilcke <jeffrey@ethereum.org>
This commit replaces the deep-copy based state revert mechanism with a
linear complexity journal. This commit also hides several internal
StateDB methods to limit the number of ways in which calling code can
use the journal incorrectly.
As usual consultation and bug fixes to the initial implementation were
provided by @karalabe, @obscuren and @Arachnid. Thank you!
