ports/80274: GDB console problem (ddd-3.3.10 with FreeBSD 5.4-STABLE)

Sat Apr 23 09:10:14 UTC 2005

>Number:         80274
>Category:       ports
>Synopsis:       GDB console problem (ddd-3.3.10 with FreeBSD 5.4-STABLE)
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Apr 23 09:10:13 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Uranus <uranus at it.muds.net>
>Release:        FreeBSD 5.4-STABLE i386
>Organization:
>Environment:
System: FreeBSD it.muds.net 5.4-STABLE FreeBSD 5.4-STABLE #0: Wed Apr 20 01:23:46 CST 2005 root at it.muds.net:/usr/obj/usr/src/sys/ED i386

>Description:
The `GDB console' is a box, which is in the bottom of the DDD GUI.
It was broken since FreeBSD 5.2-CURRENT with any xorg lib versions.
While I input any two characters after the (gdb) prompt without hit `enter' key,
I will get the following error messages after my input characters:
	Undefined command: "".  Try "help".

I tried to find out the problem,
but I don't have enough knowledge about the Xwindow event system.

The following steps are my simply worked about:

1. compile the ddd without optimization flags and append `-ggdb'
2. load ddd by gdb, set a breakpoint at LiterateA.C:142
3. start the ddd
4. input `continue' until the program be blocked.
   We can see some messages:
--------------------------------------------------------------------------
Starting program: /usr/ports/devel/ddd/work/ddd-3.3.10/ddd/ddd

Breakpoint 1, LiterateAgent::write (this=0x833ec00,
    data=0x84a530c "GNU DDD 3.3.10 (i386-portbld-freebsd5.4), by Dorothea L?keh
142     {
(gdb) cont
Continuing.

Breakpoint 1, LiterateAgent::write (this=0x833ec00,
    data=0x84a530c "Copyright ?1995-1999 Technische Universität Braunschweig, Germany.\n", length=68) at LiterateA.C:142
142     {
(gdb)
Continuing.

Breakpoint 1, LiterateAgent::write (this=0x833ec00,
    data=0x84a530c "Copyright ?1999-2001 Universität Passau, Germany.\n",
    length=51) at LiterateA.C:142
142     {
(gdb)
Continuing.

<omitted>

Breakpoint 1, LiterateAgent::write (this=0x833ec00,
    data=0x856ab0c "info files\n", length=11) at LiterateA.C:142
142     {
(gdb)
Continuing.

Breakpoint 1, LiterateAgent::write (this=0x833ec00,
    data=0x85e388c "info program\n", length=13) at LiterateA.C:142
142     {
(gdb)

--------------------------------------------------------------------------
   We can see some intial commands which were auto sent by ddd.
   The LiterateAgent::write() got the correct command strings.

5. input any two characters without hit the `enter' key.

   We can see the follow messages in the gdb:
-------------------------------------------------------------------------- 
Breakpoint 1, LiterateAgent::write (this=0x833ec00, data=0x856a9cc ".\n",
    length=2) at LiterateA.C:142
142     {
(gdb)
-------------------------------------------------------------------------- 
   Obviously, the LiterateAgent::write() didn't get the two characters.
   It got ".\n".

6. input the `backtrace' command in the gdb.

   We can see the following stack frame information:
--------------------------------------------------------------------------
#0  LiterateAgent::write (this=0x833ec00, data=0x856bbec ".\n", length=2)
    at LiterateA.C:142
#1  0x081b6082 in GDBAgent::write (this=0x833ec00, data=0x856bbec ".\n",
    length=2) at GDBAgent.C:1684
#2  0x081bc25f in GDBAgent::write (this=0x833ec00, data=@0xbfbfe100)
    at GDBAgent.h:784
#3  0x081b626b in GDBAgent::write_cmd (this=0x833ec00, cmd=@0xbfbfe100)
    at GDBAgent.C:1701
#4  0x081b2fe3 in GDBAgent::send_user_cmd_plus (this=0x833ec00,
    cmds=@0xbfbfe080, qu_datas=@0xbfbfe070, qu_count=1,
    on_qu_array_completion=0x80e7bd8 <extra_completed>, qa_data=0x85e0180,
    qa_data_registered=@0xbfbfe06f, user_cmd={rep = 0x856bbe0},
    user_data=0x8713c00) at GDBAgent.C:597
#5  0x080e3849 in send_gdb_command (cmd={rep = 0x856b880}, origin=0x849ea00,
    callback=0, extra_callback=0, data=0x0, echo=true, verbose=true,
    prompt=true, check=true, start_undo=true) at comm-manag.C:1832
#6  0x0817d6c8 in _do_gdb_command (c=@0xbfbfe280, is_command=true)
    at Command.C:325
#7  0x0817dade in do_gdb_command (given_c=@0xbfbfe2e0, is_command=true)
    at Command.C:446
#8  0x0817e161 in gdb_command (c0=@0xbfbfe330) at Command.C:665
#9  0x080d3204 in gdb_command (command=@0xbfbfe3b0, origin=0x849ea00)
    at Command.h:199
#10 0x080f52bf in gdbChangeCB (w=0x849ea00) at editing.C:764
#11 0x2859ceed in XtCallCallbackList () from /usr/X11R6/lib/libXt.so.6
#12 0x283a7944 in _XmTextValueChanged (initiator=0x849ea00, event=0xbfbfe8e0)
    at TextStrSo.c:1489
#13 0x2838ce27 in SelfInsert (w=0x849ea00, event=0xbfbfe8e0, params=0x0,
    num_params=0x285d8cb8) at TextIn.c:1446
#14 0x285ca220 in HandleActions () from /usr/X11R6/lib/libXt.so.6
#15 0x285ca6b3 in HandleSimpleState () from /usr/X11R6/lib/libXt.so.6
#16 0x285cabc4 in _XtTranslateEvent () from /usr/X11R6/lib/libXt.so.6
#17 0x285a825a in XtDispatchEventToWidget () from /usr/X11R6/lib/libXt.so.6
#18 0x285a8bea in _XtDefaultDispatcher () from /usr/X11R6/lib/libXt.so.6
#19 0x285a8dbd in XtDispatchEvent () from /usr/X11R6/lib/libXt.so.6
#20 0x08054fba in process_next_event () at ddd.C:3239
#21 0x0811f4cb in ddd_main_loop () at mainloop.C:102
#22 0x08054ee9 in main (argc=1, argv=0xbfbfe9ec) at ddd.C:3167
--------------------------------------------------------------------------

I tried to switch the stack frames between 0 and 13 and ensure them got the incorrect input strings.
I had some curious about the frame 20.
What kind of event the process_next_event() got?
I tried to print it but I have enough knowledge to understand it and had no time to study it.
It seems to get incorrect event because I never hit the `enter' key.
I only hit two english characters.

Would anyone like to solve this problem?

>How-To-Repeat:
1. install any 5.3 or higher versions of FreeBSD OS
2. install the ports `ddd-3.3.10' (with xorg-libraries version 6.8.2 or others)
3. run the ddd program on the console's Xwindow or any other Xservers on any remote machines
4. input any two characters without hit the `enter' key
5. the problem will be happended after you input the second character immediately

Even if you installed a `clean' and `new' FreeBSD OS,
and you only installed the `ddd' ports without any shell/system settings,
the problem is also appeared.

This problem isn't appeared in FreeBSD 4.x with XFree86.
Don't try to repeat it on that environment.

>Fix:
don't know how to fix it.

>Release-Note:
>Audit-Trail:
>Unformatted: