go-ethereum/eth/tracers/directory/util.go
Matthieu Vachon 7f8926e716 Backporting extended-tracer branch
We backported branch `extended-tracer` at commit 3078dfe80b back to v1.13.5 of Geth.

To achieve the backport, we did:
- git checkout -b extended-tracer-squashed
- git reset --hard 3078dfe80b
- git reset --mixed fc380f52ef # This was the latest merged commit not from `extended-tracer` branch
- git commit -A -m "<This message>"
- git checkout v1.13.5
- git checkout -b extended-tracer-backport-v1.13.5
- git cherry-pick extended-tracer-squashed
2024-02-06 13:06:08 -05:00

47 lines
1.6 KiB
Go

// Copyright 2023 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package directory
import (
"errors"
"fmt"
"github.com/ethereum/go-ethereum/core/vm"
)
const (
memoryPadLimit = 1024 * 1024
)
// GetMemoryCopyPadded returns offset + size as a new slice.
// It zero-pads the slice if it extends beyond memory bounds.
func GetMemoryCopyPadded(m *vm.Memory, offset, size int64) ([]byte, error) {
if offset < 0 || size < 0 {
return nil, errors.New("offset or size must not be negative")
}
if int(offset+size) < m.Len() { // slice fully inside memory
return m.GetCopy(offset, size), nil
}
paddingNeeded := int(offset+size) - m.Len()
if paddingNeeded > memoryPadLimit {
return nil, fmt.Errorf("reached limit for padding memory slice: %d", paddingNeeded)
}
cpy := make([]byte, size)
if overlap := int64(m.Len()) - offset; overlap > 0 {
copy(cpy, m.GetPtr(offset, overlap))
}
return cpy, nil
}