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

[Pedro Alves]

Pedro Alves wrote:
> What do you think of just suspending of thread, and setting a breakpoint
> at the current PC, and resuming?
>

Errrh, don't even bother to answer this question.  This method is of 
course very
fallible. The thread may be blocked on IO or on a synchronization 
object, which is
common in windows code (waiting for events).  If the thread doesn't get 
scheduled,
the breakpoint won't be hit.  There may not be any thread that is a got 
candidate
for the breakpoint - like if you have all your threads either deadlock 
or blocked.
The beauty of injecting a remote thread, is that it stops all the 
inferior threads atomically,
with minimum interference.  That leaves:

- ctrl-c event, which in some cases doesn't get through.
- DebugBreakProcess, on XP and 2003 Server and emulating it on NT < 5 / 
Win9x/ME / CE
  using code injection. One case where it could disturb the inferior 
would be
  when you can't debug a DllMain because of the CREATE_THREAD_EVENT that
  this generates, or is there a way to inhibit its propagation?
- 'suspend all threads manually, but no breakpoint' method.

> What about using the version you sent (if approved), and then work on
> this new version on top?  IMHO, it is better to have something working
> first.  (I don't believe the extra thread makes a difference 
> 99.999999999%
> of the times.)
This is still my opinion.

Cheers,
Pedro Alves