Wireshark mailing list archives
Re: Best way to handle a variable-length NULL-terminated string in a tvb
From: Stephen Fisher <steve () stephen-fisher com>
Date: Mon, 3 May 2010 11:50:15 -0600
On Mon, May 03, 2010 at 11:14:15AM -0400, Jeremy O'Brien wrote:
Actually, is there a function that will just get the length of said string? I don't need to do anything with the string itself other than add it to the proto_tree and of course increment my offset.
You could use tvb_get_ephemeral_stringz() to both fetch the string (and allocate memory) along with setting the length variable (passing it by reference as the third parameter). Then add the string to the tree using proto_tree_add_string() and pass the string and the length variables starting at the offset variable (set to 0 before starting). Then increment offset by the length This is basically what I did in epan/dissectors/packet-exec.c, but the packet data sounds a bit different from what you're working with. In the (r)exec protocol, there are four null-terminated strings that it looks for. Although, as Guy mentioned, you will have trouble (a thrown exception) with this if the final string really doesn't have a null. Perhaps you could do a search (perhaps by using tvb_find_guint8 with '\0' as your needle [search term]) to see if there is a null coming up before looking for it, otherwise just grab the final string without a null (tvb_get_string). -- Steve ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev () wireshark org> Archives: http://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-request () wireshark org?subject=unsubscribe
Current thread:
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Jeremy O'Brien (May 03)
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Jeremy O'Brien (May 03)
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Maynard, Chris (May 03)
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Jeremy O'Brien (May 08)
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Stephen Fisher (May 03)
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Maynard, Chris (May 03)
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Guy Harris (May 03)
- Re: Best way to handle a variable-length NULL-terminated string in a tvb Jeremy O'Brien (May 03)