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Wireshark-dev: Re: [Wireshark-dev] pcapng, must opt_comment string be 0-terminated?

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Sun, 1 Jan 2012 18:53:52 -0800
On Jan 1, 2012, at 3:00 PM, Martin Kaiser wrote:

> In a pcapng file, does the string stored in an opt_comment option have
> to be 0-terminated? I couldn't find anything explicit about this in the
> specification. Pcapng options have a length field, therefore I'd guess
> the 0 termination is not required. What do you think?

The Wireshark code to read pcap-NG files uses g_strndup() to make copies of the various "UTF-8 string[s]", so the strings in the file don't have to be null-terminated, and I would read the *lack* of any mention of null-termination in the spec as an indication that they don't have to be null-terminated.

I'll send the spec maintainers a note asking about this, and suggesting that the spec indicate that all strings are counted (but shouldn't contain a null byte).