Wireshark-dev: Re: [Wireshark-dev] Qt: Convert ProtoTree from QTreeWidget to Model/View
On Mon, Mar 09, 2015 at 05:25:10PM -0700, Gerald Combs wrote:
> On 3/9/15 4:14 PM, Peter Wu wrote:
> > On Mon, Mar 09, 2015 at 02:19:20PM -0700, Gerald Combs wrote:
> >> On 3/9/15 1:32 PM, Peter Wu wrote:
> >>> On Mon, Mar 09, 2015 at 11:44:21AM -0700, Gerald Combs wrote:
> >>>> On 3/9/15 7:56 AM, Peter Wu wrote:
> >>>>> Hi,
> >>>>>
> >>>>> I have recently discovered that the Qt UI gets in an inconsistent state
> >>>>> (leading to crashes) whenever a packet dialog is open and packets are
> >>>>> re-dissected. This is reported at
> >>>>> https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=11044
> >>>>>
> >>>>> Before proceeding to a reimplementation attempt using Model/View, I
> >>>>> would like to solicit for some feedback. Was the QTreeWidget choice done
> >>>>> consciously? Do you foresee issues with sharing field items via the same
> >>>>> model? Is someone already working on this?
> >>>>
> >>>> A QTreeWidget was chosen lazily, i.e. it did the job at the time. A custom
> >>>> model might make more sense given that we have a large limit on the number
> >>>> of tree items (MAX_TREE_ITEMS = 1e6).
> >>>>
> >>>> Having independent models lets each packet dialog persist across files.
> >>>> Would a shared model still allow that?
> >>>
> >>> As far as I know, you can only have one open capture file. Correct me if
> >>> I am wrong.
> >>
> >> That's correct. That's also *exactly* why many of the Qt dialogs catch
> >> captureFileClosing and disconnect themselves from the current capture file.
> >> If a user wants packet dialogs from multiple capture files spread across
> >> multiple monitors I'm not going to question her motives.
> >
> > So was your comment more like a wishlist feature or did you mean
> > persistence across packet selections?
>
> I mean persistence across files. In the Qt UI I can do the following today:
>
> - Open a.pcap.
> - Double-click packet 12, which opens packet 12 in a separate window.
> - Close a.pcap.
> - Open b.pcap
> - Select packet 15.
> - Compare packet 12 from a.pcap with packet 15 from b.pcap.
>
> The I/O graph, capture file properties, conversations, endpoints, and other
> dialogs behave in a similar fashion, e.g. I can compare the TCP
> conversations across files from the same application instance.
Oh, this is a new feature in the Qt UI. I thought it was something that
already exists in GTK+ and since Qt crashed, I limited testing to GTK+.
> >>> Both File sets and opening files manually result in all packet dialogs
> >>> getting closed after opening a new capture (v1.99.4rc0-34-g6bc138c).
> >>> This is the current GTK+ implementation,
> >>
> >> This is annoying behavior, IMHO.
> >>
> >>> Qt crashes for the reasons mentioned in bug 11044.
> >>
> >> ...as is this. :)
> >
> > Well, "closing" a capture file should also close other dialogs right? Or
> > are you pointing at the File sets feature?
>
> Why should it? Why yank away useful information just because the user
> closes the capture file?
"Closing" suggests that you stop working with the file. This allows
resources to be released. If you now accidentally "close" that packet
dialog, you have to reopen the capture file. Then wouldn't it be more
convenient if you can work with multiple capture files and switch
between them? The implementation could use tabs (as is done for sites in
a web browser) or a dropdown select menu, or whatever).
--
Kind regards,
Peter Wu
https://lekensteyn.nl
