Can't determine number of topics of logN in VM

[asinyagin]

Hey,

I'm trying to trace log messages in vm and as I see there's no way to get number of topics of logN(). In vm.onStep() opcode's LOG for all of the numbers and info doesn't contain opcode number.

Can you please add some method to get number of topics? Probably it could be opcode number in info argument of vm.onStep() or different labels (LOG0 .. LOG4) for each logN function.

[wanderer]

the logger now does something like this

 {
  "step": 14,
  "pc": "73",
  "depth": 1,
  "opcode": "LOG1",
  "gas": "3279",
  "memory": "aabbffffffffffffffffffffffffffffffffffffffffffffffffffffffffccdd",
  "storage": [],
  "address": "0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6",
  "stack": ["ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", "0000000000000000000000000000000000000000000000000000000000000020", "0000000000000000000000000000000000000000000000000000000000000000"]
}

let me know if that works for ya @asinyagin !

[asinyagin]

@wanderer maybe I'm doing something wrong but I'm getting this log object with ethereumjs-lib 0.5.0 and nodejs v0.10.39:

{"step":28,"pc":"69","depth":0,"opcode":"LOG","gas":"74628","memory":"0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000606865792100000000000000000000000000000000000000000000000000000000","storage":[],"address":"77045e71a7a2c50903d88e564cd72fab11e82051","stack":["0000000000000000000000000000000000000000000000000000000000000004","0000000000000000000000000000000000000000000000000000000000000003","0000000000000000000000000000000000000000000000000000000000000020","0000000000000000000000000000000000000000000000000000000000000060"]}

for log2('hey!', 3, 4)

[asinyagin]

I'm using ethereumjs-utils with that fix https://github.com/ethereum/ethereumjs-util/pull/3

[wanderer]

ok i merged that PR. But if you can you should upgrade to node version 11 or 12. I think there are other things that could be broken on 10. Also Have you pulled the latest code? I'm defiantly seeing the LOG numbers in my stack trace.

[asinyagin]

Hey, @wanderer!

I've just checked ethereumjs-lib from the repo with nodejs v0.12.0 and it gives me LOG opcode. Contract:

contract Contract {
    function Contract() {
        log0("asdf");
    }
}

Tracing (the full example is here https://github.com/asinyagin/ethereumjs-test/blob/opcode-check/app.js):

function watchLog(cb) {
  vm.logReadStream().on('data', function(data) {
    console.log(data);
  });
  cb(null, vm);
}

Output

{"step":24,"pc":"62","depth":0,"opcode":"LOG","gas":"999975120","memory":"0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000606173646600000000000000000000000000000000000000000000000000000000","storage":[],"address":"77045e71a7a2c50903d88e564cd72fab11e82051","stack":["0000000000000000000000000000000000000000000000000000000000000004","0000000000000000000000000000000000000000000000000000000000000060"]}

[wanderer]

oh yeah! I forget stuff won't work on anything less than node version 0.11 . I should make a note of that in the README

On Mon, Aug 10, 2015 at 9:02 AM, Alexander Sinyagin < notifications@github.com> wrote:

Hey, @wanderer https://github.com/wanderer!

I've just checked ethereumjs-lib from the repo with nodejs v0.12.0 and it gives me LOG opcode. Contract:

contract Contract { function Contract() { log0("asdf"); } }

Tracing (the full example is here https://github.com/asinyagin/ethereumjs-test/blob/opcode-check/app.js):

function watchLog(cb) { vm.logReadStream().on('data', function(data) { console.log(data); }); cb(null, vm); }

Output

{"step":24,"pc":"62","depth":0,"opcode":"LOG","gas":"999975120","memory":"0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000606173646600000000000000000000000000000000000000000000000000000000","storage":[],"address":"77045e71a7a2c50903d88e564cd72fab11e82051","stack":["0000000000000000000000000000000000000000000000000000000000000004","0000000000000000000000000000000000000000000000000000000000000060"]}

— Reply to this email directly or view it on GitHub https://github.com/ethereum/ethereumjs-lib/issues/114#issuecomment-129373221 .

[asinyagin]

There's a problem with LOG opcode. I want to get topics from the stack but I need to know number of them. I could get it from opcode label (LOG0, LOG1, etc), but info.opcode is always LOG without number (see https://github.com/ethereum/ethereumjs-lib/blob/master/lib/vm/opcodes.js#L138). Also, I could get number of topics if I have a hexadecimal opcode (0xa0, 0xa1, etc), but info doesn't have it.

[romanman]

@wanderer , any idea looks like more than version of the nodejs ?

[kumavis]

reopening this...

[asinyagin]

The problem is solved in https://github.com/ethereum/ethereumjs-vm

@wanderer @kumavis I can close the issue, right?

[wanderer]

Yep it should be solved

On Thu, Aug 13, 2015 at 2:09 PM, Alexander Sinyagin < notifications@github.com> wrote:

The problem is solved in https://github.com/ethereum/ethereumjs-vm

@wanderer https://github.com/wanderer @kumavis https://github.com/kumavis I can close the issue, right?

— Reply to this email directly or view it on GitHub https://github.com/ethereum/ethereumjs-lib/issues/114#issuecomment-130688006 .