1. Adding Additional Functionality to the Wireshark GUI with GTK+
June 18, 2009
Stephen Fisher
Wireshark Core Developer
Network Engineer
SHARKFEST '09
Stanford University
June 15-18, 2009

2. What is GTK+
GTK+ is short for the GIMP Toolkit. It was originally created for use by the GNU Image Manipulation Program(GIMP).
GTK+ is available for Unix (X), Microsoft Windows and MacOS X .
GTK+ is written in C and comes with a C based API. APIs for other languages are available.

3. How Wireshark uses GTK+
Almost all GUI presentations in Wireshark are done through GTK+. A notable exception is the native Microsoft Windows File Save dialogs. 3

4. The Export Objects feature
In the GUI, go to:
Find
Export
Objects
We will be studying how the the HTTP Export Object’s GUI was created. 4

5. Main Menu To Export Object
gtk/main_menu.c
The underline in front of a letter means that letter is the shortcut key in the menu.
gtk/export_object_http.c
We use _U_ to tell
gcc that the parameter is unused in the function.
gtk/export_object.c 5

6. Creating the Window
gtk/export_object.c: export_object_window() continued
gtk/export_object.h:
epan/prefs.h:
(pixels) 6

7. Creating the Window(cont.)
gtk/export_object.c: export_object_window() continued 7

8. Creating the Window(cont.)
gtk/export_object.c: export_object_window() continued 8

9. Creating the Window(cont.)
gtk/export_object.c: export_object_window() continued 9

10. Creating the Window(cont.)
gtk/export_object.c: export_object_window() continued
(Repeated for each column…) 10

11. Creating the Window(cont.)
gtk/export_object.c: export_object_window() continued 11

12. Creating the Window(cont.)
gtk/export_object.c: export_object_window() continued
(repeated for each button …) 12

13. Creating the Window(cont.)
gtk/export_object.c: export_object_window() continued 13

14. The Finished Window 14

15. Window Filled With Tap Data15

16. Further reading GTK+ Reference Manual:
GTK+ Index of All Symbols (functions and such):
GTK+ 2.0 Tree View Tutorial:
Wireshark Developer’s Guide:
Wireshark Developer README:
or doc/README.developer in source code tree 16

17. Questions ?
I’m happy to answer any of your questions now, after this session or any time you see me during the conference.
Ask other core and non-core developers; a number of which are proficient at GTK programming.
Ask them on the mailing list (subscription required to get the responses to your question). I am subscribed to this mailing list.
Review existing code in the gtk/ directory in the source code tree 17