In this commit, core/types's types learn how to encode and decode
themselves as JSON. The encoding is very similar to what the RPC API
uses. The RPC API is missing some output fields (e.g. transaction
signature values) which will be added to the API in a later commit. Some
fields that the API generates are ignored by the decoder methods here.
This CL makes several refactors:
- Define a Tracer interface, implementing the `CaptureState` method
- Add the VM environment as the first argument of
`Tracer.CaptureState`
- Rename existing functionality `StructLogger` an make it an
implementation of `Tracer`
- Delete `StructLogCollector` and make `StructLogger` collect the logs
directly
- Change all callers to use the new `StructLogger` where necessary and
extract logs from that.
- Deletes the apparently obsolete and likely nonfunctional 'TraceCall'
from the eth API.
Callers that only wish accumulated logs can use the `StructLogger`
implementation straightforwardly. Callers that wish to efficiently
capture VM traces and operate on them without excessive copying can now
implement the `Tracer` interface to receive VM state at each step and
do with it as they wish.
This CL also removes the accumulation of logs from the vm.Environment;
this was necessary as part of the refactor, but also simplifies it by
removing a responsibility that doesn't directly belong to the
Environment.
This implements a generic approach to enabling soft forks by allowing
anyone to put in hashes of contracts that should not be interacted from.
This will help "The DAO" in their endevour to stop any whithdrawals from
any DAO contract by convincing the mining community to accept their code
hash.
Consensus rules dictate that objects can only be removed during the
finalisation of the transaction (i.e. after all calls have finished).
Thus calling a suicided contract twice from the same transaction:
A->B(S)->ret(A)->B(S) results in 2 suicides. Calling the suicided
object twice from two transactions: A->B(S), A->B, results in only one
suicide and a call to an empty object.
Our current debug tracing functionality replays all transaction that
were executed prior to the targetted transaction in order to provide
the user with an accurate trace.
As a side effect to calling StateDB.IntermediateRoot it also deletes any
suicides objects. Our tracing code never calls this function because it
isn't interested in the intermediate root. Becasue of this it caused a
bug in the tracing code where transactions that were send to priviously
deleted objects resulted in two suicides rather than one suicide and a
call to an empty object.
Fixes#2542
We used to have reporting of bad blocks, but it was disabled
before the Frontier release. We need it back because users
are usually unable to provide the full RLP data of a bad
block when it occurs.
A shortcoming of this particular implementation is that the
origin peer is not tracked for blocks received during eth/63
sync. No origin peer info is still better than no report at
all though.
This fixes an issue where it's theoretical possible to cause a consensus
failure when hitting the lower end of the difficulty, though pratically
impossible it's worth a fix.
Shutting down geth prints hundreds of annoying error messages in some
cases. The errors appear because the Stop method of eth.ProtocolManager,
miner.Miner and core.TxPool is asynchronous. Left over peer sessions
generate events which are processed after Stop even though the database
has already been closed.
The fix is to make Stop synchronous using sync.WaitGroup.
For eth.ProtocolManager, in order to make use of WaitGroup safe, we need
a way to stop new peer sessions from being added while waiting on the
WaitGroup. The eth protocol Run function now selects on a signaling
channel and adds to the WaitGroup only if ProtocolManager is not
shutting down.
For miner.worker and core.TxPool the number of goroutines is static,
WaitGroup can be used in the usual way without additional
synchronisation.
This is necessary for external users of the go-ethereum code who want to, for instance, build a custom node that plays back transactions, as core.ApplyTransaction requires a ChainConfig as a parameter.
