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
}