Re: [Patch] Win32 gdbserver new interrupt support, and attach to process fix.

[Pedro Alves <pedro_alves@portugalmail.pt>]

Pedro Alves escreveu:
> Lerele wrote:
>
>> It seems after all the solution proposed may be the best resort, 
>> instead of the last: more compatible, less interfereable with child, 
>> however a bit more difficult to write.
>> In fact, the first version of interrupt code I wrote several months 
>> ago worked like that (I still keep a copy somewhere). It worked, but 
>> it was buggy, so I dropped it and wrote that other simpler new version.
>> This other solution may be the one-for-all solution, because it uses 
>> rather more standard Win32 calls.
>
> The more I search for a *clean* way to do it in WinCE, the more I'm
> inclined to drop the create_a_remote_thread idea.  A bit of
> googling and reading old MSFT docs indicates that older debuggers either
> suspend all threads with SuspendThread (like you suggest, or get the
> main thread's PC (EIP) and set a breakpoint there, which should be
> simpler.  (I would still have to do a little more work for WinCE
> because the address might not be physically writable.)  I think I
> read somewhere that recent MSVC uses DebugBreakProcess, and hides the 
> fact
> that the break was inside ntdll.dll, or wherever, by switching threads...
>
> What do you think of just suspending of thread, and setting a breakpoint
> at the current PC, and resuming?
>

The GoVest debugger (*) uses something even simpler:
- Suspend main thread,
- Set single-step / trace flag (i386)
- Resume thread

(*) http://www.geocities.com/GoVest/

Cheers,
Pedro Alves