go-ethereum/ethchain/asm.go

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package ethchain
import (
"fmt"
"github.com/ethereum/eth-go/ethutil"
"math/big"
)
func Disassemble(script []byte) (asm []string) {
pc := new(big.Int)
for {
if pc.Cmp(big.NewInt(int64(len(script)))) >= 0 {
return
}
// Get the memory location of pc
val := script[pc.Int64()]
// Get the opcode (it must be an opcode!)
op := OpCode(val)
asm = append(asm, fmt.Sprintf("%v", op))
switch op {
case oPUSH: // Push PC+1 on to the stack
pc.Add(pc, ethutil.Big1)
data := script[pc.Int64() : pc.Int64()+32]
val := ethutil.BigD(data)
var b []byte
if val.Int64() == 0 {
b = []byte{0}
} else {
b = val.Bytes()
}
asm = append(asm, fmt.Sprintf("0x%x", b))
pc.Add(pc, big.NewInt(31))
case oPUSH20:
pc.Add(pc, ethutil.Big1)
data := script[pc.Int64() : pc.Int64()+20]
val := ethutil.BigD(data)
var b []byte
if val.Int64() == 0 {
b = []byte{0}
} else {
b = val.Bytes()
}
asm = append(asm, fmt.Sprintf("0x%x", b))
pc.Add(pc, big.NewInt(19))
}
pc.Add(pc, ethutil.Big1)
}
return
}