nimbus-eth1/nimbus/vm/computation.nim

130 lines
4.0 KiB
Nim

# Nimbus
# Copyright (c) 2018 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed except according to those terms.
import
strformat, strutils, sequtils, macros, terminal, math, tables,
eth_common,
../constants, ../errors, ../validation, ../vm_state, ../logging, ../vm_types,
./interpreter/[opcode_values, gas_meter, gas_costs, vm_forks],
./code_stream, ./memory, ./message, ./stack
proc newBaseComputation*(vmState: BaseVMState, blockNumber: UInt256, message: Message): BaseComputation =
new result
result.vmState = vmState
result.msg = message
result.memory = Memory()
result.stack = newStack()
result.gasMeter.init(message.gas)
result.children = @[]
result.accountsToDelete = initTable[EthAddress, EthAddress]()
result.logEntries = @[]
result.code = newCodeStreamFromUnescaped(message.code) # TODO: what is the best repr
# result.rawOutput = "0x"
result.gasCosts = blockNumber.toFork.forkToSchedule
proc logger*(computation: BaseComputation): Logger =
logging.getLogger("vm.computation.BaseComputation")
proc isOriginComputation*(c: BaseComputation): bool =
# Is this computation the computation initiated by a transaction
c.msg.isOrigin
template isSuccess*(c: BaseComputation): bool =
c.error.isNil
template isError*(c: BaseComputation): bool =
not c.isSuccess
proc shouldBurnGas*(c: BaseComputation): bool =
c.isError and c.error.burnsGas
proc shouldEraseReturnData*(c: BaseComputation): bool =
c.isError and c.error.erasesReturnData
func bytesToHex(x: openarray[byte]): string {.inline.} =
## TODO: use seq[byte] for raw data and delete this proc
foldl(x, a & b.int.toHex(2).toLowerAscii, "0x")
proc prepareChildMessage*(
c: var BaseComputation,
gas: GasInt,
to: EthAddress,
value: UInt256,
data: seq[byte],
code: seq[byte],
options: MessageOptions = newMessageOptions()): Message =
var childOptions = options
childOptions.depth = c.msg.depth + 1
result = newMessage(
gas,
c.msg.gasPrice,
c.msg.origin,
to,
value,
data,
code.bytesToHex, # TODO: use seq[byte] for Message as well
childOptions)
func output*(c: BaseComputation): seq[byte] =
if c.shouldEraseReturnData:
@[]
else:
c.rawOutput
func `output=`*(c: var BaseComputation, value: openarray[byte]) =
c.rawOutput = @value
proc outputHex*(c: BaseComputation): string =
if c.shouldEraseReturnData:
return "0x"
c.rawOutput.bytesToHex
proc registerAccountForDeletion*(c: var BaseComputation, beneficiary: EthAddress) =
if c.msg.storageAddress in c.accountsToDelete:
raise newException(ValueError,
"invariant: should be impossible for an account to be " &
"registered for deletion multiple times")
c.accountsToDelete[c.msg.storageAddress] = beneficiary
proc addLogEntry*(c: var BaseComputation, account: EthAddress, topics: seq[UInt256], data: seq[byte]) =
c.logEntries.add((account, topics, data))
# many methods are basically TODO, but they still return valid values
# in order to test some existing code
proc getAccountsForDeletion*(c: BaseComputation): seq[(string, string)] =
# TODO
if c.isError:
result = @[]
else:
result = @[]
proc getLogEntries*(c: BaseComputation): seq[(string, seq[UInt256], string)] =
# TODO
if c.isError:
result = @[]
else:
result = @[]
proc getGasRefund*(c: BaseComputation): GasInt =
if c.isError:
result = 0
else:
result = c.gasMeter.gasRefunded + c.children.mapIt(it.getGasRefund()).foldl(a + b, 0'i64)
proc getGasUsed*(c: BaseComputation): GasInt =
if c.shouldBurnGas:
result = c.msg.gas
else:
result = max(0, c.msg.gas - c.gasMeter.gasRemaining)
proc getGasRemaining*(c: BaseComputation): GasInt =
if c.shouldBurnGas:
result = 0
else:
result = c.gasMeter.gasRemaining