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authorDeterminant <[email protected]>2020-06-28 14:47:41 -0400
committerDeterminant <[email protected]>2020-06-28 14:47:41 -0400
commitd235e2c6a5788ec4a6cff15a16f56b38a3876a0d (patch)
tree5f2727f7a50ee5840f889c82776d3a30a88dd59b /core/vm/stack.go
parent13ebd8bd9468e9d769d598b0ca2afb72ba78cb97 (diff)
...
Diffstat (limited to 'core/vm/stack.go')
-rw-r--r--core/vm/stack.go95
1 files changed, 95 insertions, 0 deletions
diff --git a/core/vm/stack.go b/core/vm/stack.go
new file mode 100644
index 0000000..4c1b9e8
--- /dev/null
+++ b/core/vm/stack.go
@@ -0,0 +1,95 @@
+// 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 vm
+
+import (
+ "fmt"
+ "math/big"
+)
+
+// 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 []*big.Int
+}
+
+func newstack() *Stack {
+ return &Stack{data: make([]*big.Int, 0, 1024)}
+}
+
+// Data returns the underlying big.Int array.
+func (st *Stack) Data() []*big.Int {
+ return st.data
+}
+
+func (st *Stack) push(d *big.Int) {
+ // NOTE push limit (1024) is checked in baseCheck
+ //stackItem := new(big.Int).Set(d)
+ //st.data = append(st.data, stackItem)
+ st.data = append(st.data, d)
+}
+func (st *Stack) pushN(ds ...*big.Int) {
+ st.data = append(st.data, ds...)
+}
+
+func (st *Stack) pop() (ret *big.Int) {
+ ret = st.data[len(st.data)-1]
+ st.data = st.data[:len(st.data)-1]
+ return
+}
+
+func (st *Stack) len() int {
+ return len(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(pool *intPool, n int) {
+ st.push(pool.get().Set(st.data[st.len()-n]))
+}
+
+func (st *Stack) peek() *big.Int {
+ return st.data[st.len()-1]
+}
+
+// Back returns the n'th item in stack
+func (st *Stack) Back(n int) *big.Int {
+ return st.data[st.len()-n-1]
+}
+
+func (st *Stack) require(n int) error {
+ if st.len() < n {
+ return fmt.Errorf("stack underflow (%d <=> %d)", len(st.data), n)
+ }
+ return nil
+}
+
+// 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("#############")
+}