Re: [PATCH 1/2] [GDBserver] Check input interrupt after reading in a packet

[Pedro Alves <palves at redhat dot com>]

On 01/26/2016 09:58 AM, Yao Qi wrote:

> +  /* The '\003' may appear after some packet, and check it in the buffer,
> +     so that we can process the interrupt in time.  */

I can't parse seem to parse this correctly.

I think we should expand the explanation, like:

  /* The readchar above may have already read a '\003' out of the socket and
   moved it to the local buffer.  For example, when GDB sends vCont;c immediately
   followed by interrupt (see gdb.base/interrupt-noterm.exp).  As soon as we see
   the vCont;c, we'll resume the inferior and wait.  Since we've already moved
   the '\003' to the local buffer, SIGIO won't help.  In that case, if we don't
   check for interrupt after the vCont;c packet, the interrupt character would
   stay in the buffer unattended until after the next (unrelated) stop.  */

> +  if (readchar_bufcnt > 0 && *readchar_bufp == '\003')

This should be a "while" instead of a single "if".

> +    {
> +      /* Consume the interrupt character in the buffer.  */
> +      readchar ();
> +      (*the_target->request_interrupt) ();
> +    }
> +
>    return bp - buf;
>  }

Otherwise LGTM.

Thanks,
Pedro Alves