decodescript does not parse the correct asm, show it as -123928979 #13505

decodescript/decoderawtransaction does not show the correct asm, parse it as -123928979.

What behavior did you expect? asm should be (asm:"1 62 OP_ADD 63 OP_EQUAL”)

What was the actual behavior (provide screenshots if the issue is GUI-related)? "asm": "1 98 -123928979",

How reliably can you reproduce the issue, what are the steps to do so?

$ decodescript 5101620493016387
{
 "asm": "1 98 -123928979",
 "type": "nonstandard",
 "p2sh": "2MvPLsDfmrW1repgmEdL51ZR4Vhc1LDxRVS",
 "segwit": {
   "asm": "0 389cb2613fb2c5c5b950ef80402abf9ac87e4a6da117bb5d5058489be3f5037c",
   "hex": "0020389cb2613fb2c5c5b950ef80402abf9ac87e4a6da117bb5d5058489be3f5037c",
   "reqSigs": 1,
   "type": "witness_v0_scripthash",
   "addresses": [
     "tb1q8zwtycflktzutw2sa7qyq24lnty8ujnd5ytmkh2stpyfhcl4qd7qqvz4c8"
   ],
   "p2sh-segwit": "2NBfsvWRZLuJhWhJ8TZM89FSwZeT82xCxkR"
 }
}

decoderawtransaction 0100000001e2d4fe69fbfa62beac61da2a07ae84d96e3e1c14cdee348cf3c84efd20eda37d00000000085101620493016387ffffffff0160ceab070000000017a9143f58b4f7b14847a9083694b9b3b52a4cea2569ed8700000000
{
  "txid": "e8a9df4f3b5f5ff454ab96083fca8f8375359df26051ef2831bbc07e93788b27",
  "hash": "e8a9df4f3b5f5ff454ab96083fca8f8375359df26051ef2831bbc07e93788b27",
  "version": 1,
  "size": 91,
  "vsize": 91,
  "weight": 364,
  "locktime": 0,
  "vin": [
    {
      "txid": "7da3ed20fd4ec8f38c34eecd141c3e6ed984ae072ada61acbe62fafb69fed4e2",
      "vout": 0,
      "scriptSig": {
        "asm": "1 98 -123928979",
        "hex": "5101620493016387"
      },
      "sequence": 4294967295
    }
  ],
  "vout": [
    {
      "value": 1.28700000,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_HASH160 3f58b4f7b14847a9083694b9b3b52a4cea2569ed OP_EQUAL",
        "hex": "a9143f58b4f7b14847a9083694b9b3b52a4cea2569ed87",
        "reqSigs": 1,
        "type": "scripthash",
        "addresses": [
          "2My2ApqGcoNXYceZC4d7fipBu4GodkbefHD"
        ]
      }
    }
  ]
}

What version of Bitcoin Core are you using, where did you get it (website, self-compiled, etc)?

$ ./bitcoind --version
Bitcoin Core Daemon version v0.16.99.0-e4082d59f
Copyright (C) 2009-2018 The Bitcoin Core developers

What type of machine are you observing the error on (OS/CPU and disk type)?

$ uname -a
Darwin MacBook-Pro.local 17.5.0 Darwin Kernel Version 17.5.0: Fri Apr 13 19:32:32 PDT 2018; root:xnu-4570.51.2~1/RELEASE_X86_64 x86_64

What you want is 51013e93013f87.

hi @ken2812221

according to https://en.bitcoin.it/wiki/Script below table, I expect it is translated to [ 51 62 OP_ADD 63 87] or something human can understand not just garbage minus integer.

| 1 | OP_CODE | description |:---:|:---------:|:----------------------------------------------------------------| |51 | OP_1 | The number 1 is pushed onto the stack. |01 | 0x01 | The next opcode bytes is data to be pushed onto the stack
|62 | data | 0x62 |04 | OP_4 | The next opcode bytes is data to be pushed onto the stack(4bytes) |93 | OP_ADD | a is added to b. |01 | OP_1 | The number 1 is pushed onto the stack |63 | data | 0x63 is pushed onto the stack. |87 | OP_EQUAL| Returns 1 if the inputs are exactly equal, 0 otherwise.

0x62 is 98 in decimal, the assembly is showing the decimal scriptnum value

OP_4 is going to treat the next 4 bytes (OP_ADD OP_1 0x63 OP_EQUAL) as data which happens to be scriptnum -123928979

perhaps you want 51016293016387 ?

use bx to decode it

$ ./bx script-decode 5101620493016387
1 [62] [93016387]
$ ./bx script-decode 93016387
add [63] equal

I expect it is decode to [93016387] not and decode to [-123928979]

You're confusing hexadecimal with decimal. The numbers outputed by bx are in hex, decodescript outputs in decimal. Hex 93016387 is -123928979 decimal.

hi @sipa thanks you for your answer.

$decodescript 5101620493016387
>>"asm": "1 98 -123928979",
$decodescript -123928979 
>>argument must be hexadecimal string (not '-123928979')

OK because -123928979 mean 93016387

>>"asm": "OP_ADD 99 OP_EQUAL",

why don't directly give user below output

$decodescript 5101620493016387
>>"asm": "1 98 OP_ADD 99 OP_EQUAL",

@passionofvc read my comment. you have an extra 0x04 byte