RE: Problems: Remote debugging over UDP.

RE: Problems: Remote debugging over UDP.

[Arun Vishwanathan]

So how is it that gdb supports the UDP protocol when the server itself
doesn't support it?  

-----Original Message-----
From: gdb-owner@sources.redhat.com [mailto:gdb-owner@sources.redhat.com]
On Behalf Of Daniel Jacobowitz
Sent: Tuesday, February 24, 2004 8:03 PM
To: Atul Talesara
Cc: gdb@sources.redhat.com
Subject: Re: Problems: Remote debugging over UDP.


On Tue, Feb 24, 2004 at 06:31:39PM +0530, Atul Talesara wrote:
> Is it that "gdbserver" doesn't talk over UDP???

That's correct.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

Re: Problems: Remote debugging over UDP.

[Daniel Jacobowitz]

On Tue, Feb 24, 2004 at 08:25:09PM +0530, Arun Vishwanathan wrote:
> So how is it that gdb supports the UDP protocol when the server itself
> doesn't support it?  

There are many other remote target implementations besides gdbserver. 
I implemented UDP support for a MontaVista-local KGDB stub which spoke
UDP; I don't know what ever happened to that code.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

Re: Problems: Remote debugging over UDP.

[Daniel Jacobowitz]

On Tue, Feb 24, 2004 at 06:31:39PM +0530, Atul Talesara wrote:
> Is it that "gdbserver" doesn't talk over UDP???

That's correct.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

RE: Problems: Remote debugging over UDP.

[Atul Talesara]

Is it that "gdbserver" doesn't talk over UDP???
Because when I do the following:

gdbserver udp:my_system:9000 test_program

I don't see the port "9000" (with netstat -elp)to be occupied
by any of the processes! Whereas I can see the port used when
I do the same over TCP.

Also, "strace" revealed that gdbserver NEVER opens a SOCK_DGRAM
(UDP) socket!!! Here are the last few lines that actually opens
the socket:

-------------------------------------------------------
                        .
                        .
                        .

socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 3
               ^^^^^^^^^^^^^^
setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
bind(3, {sin_family=AF_INET, sin_port=htons(0),
sin_addr=inet_addr("0.0.0.0")}}, 16) = 0
listen(3, 1)                            = 0
accept(3,  <unfinished ...>
            ^^^^^^^^^^^^^^^  <-- I kill strace here
-------------------------------------------------------

At this point when I again do netstat, I see gdbserver running
on some ephemeral TCP port and not UDP port 9000 :-(
since port '0' is passed to "bind()" call.


This is the GDB that I'm using and gdbserver coupled with it.
-------------------------------------------------------
bash-2.05b$ ~/local/bin/gdb -v
GNU gdb 20040223
Copyright 2004 Free Software Foundation, Inc.
-------------------------------------------------------

	Thanks in advance.


Atul P Talesara
------------------------------------------------------------------
When "Winning" and "Losing" don't have any meaning, that is when
    the real game happens, play happens.  Otherwise it is war.
          War has a significance for Winning or Losing.
                                                         -Sri Sri
------------------------------------------------------------------


> -----Original Message-----
> From: gdb-owner@sources.redhat.com
[mailto:gdb-owner@sources.redhat.com]
> On Behalf Of Atul Talesara
> Sent: Monday, February 23, 2004 6:41 PM
> To: gdb@sources.redhat.com
> Subject: Problems: Remote debugging over UDP.
> 
> Hello Everybody,
> I have had problems while attempting remote debugging over UDP.
> For ease, I used same system as target and host.  Also, I'm
> logged in as "root" on both the consoles.
> 
> On Target I do the following:
> ------------------------------
> gdbserver udp:localhost:9090 ./hello
>           ^^^
> 
> I get the following output:
> Process ./hello created; pid=2135
> 
> 
> On Host I do:
> --------------
> gdb ./hello
> 
> gdb> target remote udp:localhost:9090
>                    ^^^
> 
> and get the following o/p:
> Remote debugging using udp:localhost:9090
> Couldn't establish connection to remote target
> putpkt: write failed: connection refused.
> 
> 
> When I omit the "UDP" part, i.e. use TCP, everything
> works smoothly w same steps!  Am I missing something important
> here because of which GDB over UDP is not working?  Can anyone
> pl provide some inputs?
> 
> 
> Thanks and Regards,
> Atul P Talesara
> ------------------------------------------------------------------
>  When "Winning" and "Losing" don't have any meaning, that is when
>     the real game happens, play happens.  Otherwise it is war.
>           War has a significance for Winning or Losing.
>                                                          -Sri Sri
> ------------------------------------------------------------------

Problems: Remote debugging over UDP.

[Atul Talesara]

Hello Everybody,
I have had problems while attempting remote debugging over UDP.
For ease, I used same system as target and host.  Also, I'm
logged in as "root" on both the consoles.

On Target I do the following:
------------------------------
gdbserver udp:localhost:9090 ./hello
          ^^^

I get the following output:
Process ./hello created; pid=2135


On Host I do:
--------------
gdb ./hello

gdb> target remote udp:localhost:9090
                   ^^^

and get the following o/p:
Remote debugging using udp:localhost:9090
Couldn't establish connection to remote target
putpkt: write failed: connection refused.


When I omit the "UDP" part, i.e. use TCP, everything
works smoothly w same steps!  Am I missing something important
here because of which GDB over UDP is not working?  Can anyone
pl provide some inputs?


Thanks and Regards,
Atul P Talesara
------------------------------------------------------------------
 When "Winning" and "Losing" don't have any meaning, that is when
    the real game happens, play happens.  Otherwise it is war.
          War has a significance for Winning or Losing.
                                                         -Sri Sri
------------------------------------------------------------------