Re: [patch] gdbserver: Add support for Z0/Z1 packets

[Aleksandar Ristovski <aristovski@qnx.com>]

Pedro Alves wrote:
> On Wednesday 24 June 2009 19:50:44, Aleksandar Ristovski wrote:
>> Pedro Alves wrote:
>>> On Tuesday 23 June 2009 16:17:58, Aleksandar Ristovski wrote:
>>>> Pedro Alves wrote:
>>>>> On Monday 22 June 2009 20:38:50, Aleksandar Ristovski wrote:
>>>>>
>>>>>>> Z0 and Z1 breakpoints also take a 'len' argument, just
>>>>>>> like Z2-Z4.  You should also pass those down.
>>>>>>>
>>>>>>> But, Let's take a step back --- why not just rename the
>>>>>>> insert_watchpoint|remove_watchpoint functions to insert_point,remove_point,
>>>>>>> and relax the type checks in server.c:
>>>>>> But either way is fine with me - just let me know.
>>>>> I'd prefer the approach I suggested, and worry about splitting
>>>>> the breakpoints from watchpoints API if/when we actually need it.
>>>>>
>>>> Ok, then that version is committed.
>>> Well, we had never seen "that" version
>> Ok, to rectify this I am attaching two versions: one if I 
>> revert the changes I committed and the other is diff to what 
>> is in now.
>>
>>  > ... and you bypassed the "rename" suggestion...
>>
>> I did not do any renaming - I think it is not terribly 
>> confusing since both in target.h comment and server.c 'Z' 
>> case it is made very clear that it handles both breakpoints 
>> and watchpoints (i.e. I don't find it any clearer if it was 
>> called "insert_point"... it would still require reading the 
>> comment in target.h)
> 
> 
> Urgh, I was just about to press the send button when I saw
> this message of yours.  This version corrects a few troubles
> with the previous commit (see ChangeLog) (one of them I still
> see in your new patch) and I've tested it on x86_64-linux.
> Aleksandar, please, please, do run the testsuite (and state
> that you have) when posting patches.  E.g., we could have caught
> the vKill issue that Pierre fixed when we made only linux
> report multi-process (the testsuite runs in "target remote"
> mode, hence with multi-process off most of the way).
> 

And just another small note:

+	    require_running (own_buf);
+	    if (insert && the_target->insert_point != NULL)
+	      res = (*the_target->insert_point) (type, addr, len);
+	    else if (!insert && the_target->remove_point != NULL)
+	      res = (*the_target->remove_point) (type, addr, len);
+	    break;

They should either both be present or none. In the gdb 
document, there is implementation note that reads:

Implementation notes: A remote target shall return an empty 
string for an un-recognized breakpoint or watchpoint packet 
type. A remote target shall support either both or neither 
of a given `Ztype...' and `ztype...' packet pair. To
avoid potential problems with duplicate packets, the 
operations should be imple-mented in an idempotent way.

So, I would make it something like I proposed (if either is 
NULL, it's unsupported - also makes a clear statement to new 
target implementors).


Thanks
-- 
Aleksandar Ristovski
QNX Software Systems