Wireshark · Wireshark-dev: Re: [Wireshark-dev] Checking address in WMEM

[Dario Lombardo <dario.lombardo.ml@xxxxxxxxx>]

On Thu, Jan 26, 2017 at 2:11 PM, Evan Huus <eapache@xxxxxxxxx> wrote:

Each block can consist of multiple chunks, so you need a second, inner
loop. You can do this with WMEM_CHUNK_NEXT.

Do note, however, that:
- you'll be iterating over every piece of memory allocated in this
scope, which will probably be quite expensive

I get it.

 

- your code will fail any time wmem chooses a different allocator
(this happens in CI, and occasionally elsewhere as well)

I don't get this. Can you explain it a little bit?

 

What problem specifically are you trying to solve? There may be an easier way.

Evan

The general problem is: a function takes a wmem string as input. This function can do wmem_realloc, then I need the scope the variable lives in. If the caller gives the wrong scope, I have a crash. The question is how can I check that the variable is consistent with the provided scope? Despite very expensive, I could have this check in debug only to reduce the debug time.