erigon-pulse/core/vm/stack/stack.go
2020-06-05 17:45:56 +03:00

96 lines
2.3 KiB
Go

// Copyright 2014 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 stack
import (
"fmt"
"github.com/holiman/uint256"
)
// Stack is an object for basic stack operations. Items popped to the stack are
// expected to be changed and modified. stack does not take care of adding newly
// initialised objects.
type Stack struct {
Data []uint256.Int
}
func New(n ...int) *Stack {
if len(n) > 0 {
return &Stack{make([]uint256.Int, 0, n[0])}
}
return &Stack{}
}
// Data returns the underlying uint256.Int array.
func (st *Stack) GetData() []uint256.Int {
return st.Data
}
func (st *Stack) Push(d *uint256.Int) {
// NOTE push limit (1024) is checked in baseCheck
st.Data = append(st.Data, *d)
}
func (st *Stack) Pop() uint256.Int {
ret := st.Data[len(st.Data)-1]
st.Data = st.Data[:len(st.Data)-1]
return ret
}
func (st *Stack) Len() int {
return len(st.Data)
}
func (st *Stack) Cap() int {
return cap(st.Data)
}
func (st *Stack) Swap(n int) {
st.Data[st.Len()-n], st.Data[st.Len()-1] = st.Data[st.Len()-1], st.Data[st.Len()-n]
}
func (st *Stack) Dup(n int) {
st.Push(&st.Data[st.Len()-n])
}
func (st *Stack) Peek() *uint256.Int {
return &st.Data[st.Len()-1]
}
// Back returns the n'th item in stack
func (st *Stack) Back(n int) *uint256.Int {
return &st.Data[st.Len()-n-1]
}
func (st *Stack) Reset() {
st.Data = st.Data[:0]
}
// Print dumps the content of the stack
func (st *Stack) Print() {
fmt.Println("### stack ###")
if len(st.Data) > 0 {
for i, val := range st.Data {
fmt.Printf("%-3d %v\n", i, val)
}
} else {
fmt.Println("-- empty --")
}
fmt.Println("#############")
}