On 21-10-16 19:47, Guy Harris wrote: > On Oct 21, 2016, at 9:57 AM, Thomas Wiens <th.wi...@gmx.de> wrote: > >> This happens only when calling val_to_str inside the callback function. >> When outside, then all is Ok (getting formatted result string on failure). >> When I'm calling try_val_to_str_idx with a non existing value, then I >> get -1 as index and NULL as result as expected, so I guess the problem is: >> >> wmem_strdup_printf(wmem_packet_scope(), fmt, val); >> >> Is there a limitation when I'm using format callbacks, > > Yes. You're limited to using wmem scopes that are active even if you're *not* > in the middle of dissecting a packet; the callback is called when the result > of a dissection is being displayed or used for a custom column, and that's > not in the middle of dissecting a packet. > > Unfortunately, I don't think there's a scope for this, so you'd either have > to use NULL as the scope and explicitly free the string when you're done with > it, or use try_val_to_str() and deal with a NULL return (nothing matches) > yourself.
For my understanding, would this be covered by using val_to_str_wmem(wmem_file_scope(), val, vs, fmt); Thanks, Jaap ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev@wireshark.org> Archives: https://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://www.wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-requ...@wireshark.org?subject=unsubscribe
