go-ethereum/core/vm/contracts.libevm.go
Arran Schlosberg 04543ea837
chore: golangci-lint CI workflow (#16)
* chore: `golangci-lint` CI workflow

* fix: make `golangci-lint` happy

* chore: bump `actions/{checkout,setup-go}` versions

* chore: overhaul `.golanci.yml` config

* fix: all linter issues

* chore: exclude non-libevm linters + change deprecated option

* fix: add overflow check in example

* fix: try again; different local version?

* chore: this is trying my patience

* chore: enable `gci` and fix ordering

* chore: mark `ethclient/gethclient` test as flaky

* chore: mark `eth/catalyst` test as flaky
2024-09-12 20:31:04 +01:00

84 lines
2.8 KiB
Go

package vm
import (
"fmt"
"github.com/holiman/uint256"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/params"
)
// evmCallArgs mirrors the parameters of the [EVM] methods Call(), CallCode(),
// DelegateCall() and StaticCall(). Its fields are identical to those of the
// parameters, prepended with the receiver name. As {Delegate,Static}Call don't
// accept a value, they MUST set the respective field to nil.
//
// Instantiation can be achieved by merely copying the parameter names, in
// order, which is trivially achieved with AST manipulation:
//
// func (evm *EVM) Call(caller ContractRef, addr common.Address, input []byte, gas uint64, value *uint256.Int) ... {
// ...
// args := &evmCallArgs{evm, caller, addr, input, gas, value}
type evmCallArgs struct {
evm *EVM
caller ContractRef
addr common.Address
input []byte
gas uint64
value *uint256.Int
}
// run runs the [PrecompiledContract], differentiating between stateful and
// regular types.
func (args *evmCallArgs) run(p PrecompiledContract, input []byte) (ret []byte, err error) {
if p, ok := p.(statefulPrecompile); ok {
return p.run(args.evm.StateDB, &args.evm.chainRules, args.caller.Address(), args.addr, input)
}
return p.Run(input)
}
// PrecompiledStatefulRun is the stateful equivalent of the Run() method of a
// [PrecompiledContract].
type PrecompiledStatefulRun func(_ StateDB, _ *params.Rules, caller, self common.Address, input []byte) ([]byte, error)
// NewStatefulPrecompile constructs a new PrecompiledContract that can be used
// via an [EVM] instance but MUST NOT be called directly; a direct call to Run()
// reserves the right to panic. See other requirements defined in the comments
// on [PrecompiledContract].
func NewStatefulPrecompile(run PrecompiledStatefulRun, requiredGas func([]byte) uint64) PrecompiledContract {
return statefulPrecompile{
gas: requiredGas,
run: run,
}
}
type statefulPrecompile struct {
gas func([]byte) uint64
run PrecompiledStatefulRun
}
func (p statefulPrecompile) RequiredGas(input []byte) uint64 {
return p.gas(input)
}
func (p statefulPrecompile) Run([]byte) ([]byte, error) {
// https://google.github.io/styleguide/go/best-practices.html#when-to-panic
// This would indicate an API misuse and would occur in tests, not in
// production.
panic(fmt.Sprintf("BUG: call to %T.Run(); MUST call %T", p, p.run))
}
var (
// These lock in the assumptions made when implementing [evmCallArgs]. If
// these break then the struct fields SHOULD be changed to match these
// signatures.
_ = [](func(ContractRef, common.Address, []byte, uint64, *uint256.Int) ([]byte, uint64, error)){
(*EVM)(nil).Call,
(*EVM)(nil).CallCode,
}
_ = [](func(ContractRef, common.Address, []byte, uint64) ([]byte, uint64, error)){
(*EVM)(nil).DelegateCall,
(*EVM)(nil).StaticCall,
}
)