[Vm-dev] Re: [Pharo-users] Get "Invalid utf8 input detected" error for a filename

[Igor Stasenko]

On 24 March 2011 22:12, Eliot Miranda <eliot.miranda at gmail.com> wrote:
>
>
>
> On Thu, Mar 24, 2011 at 2:12 PM, stephane ducasse <stephane.ducasse at gmail.com> wrote:
>>
>> >
>> > Clearly we need to do a careful merge of the http://www.squeakvm.org/svn/squeak/branches/Cog/platforms tree with http://squeakvm.org/svn/squeak/trunk/platforms tree.  There are important improvements from Cog:
>> > - time based on 64-bit microseconds
>> > - better crash/logging stack backtrace reporting
>> > - concurrent lock-free external semaphore signalling
>> > - threaded stdio
>> > - vm version info
>> > - others?
>>
>> Elliot do you know if any of these issues include the fix that igor sent long time ago about the semaphore
>> for event input (because it is missing on windows) and with it we will be able to remove the polling behavior for events.
>
> No idea. Sorry.

Here it is:
primSetInputSemaphore: semaIndex
	"Set the input semaphore the VM should use for asynchronously
signaling the availability of events. Primitive. Optional."
	<primitive: 93>
	^nil


On unix (platforms/unix/vm/sqUnixMain.c):
/* set asynchronous input event semaphore  */

sqInt ioSetInputSemaphore(sqInt semaIndex)
{
  if ((semaIndex == 0) || (noEvents == 1))
    success(false);
  else
    inputEventSemaIndex= semaIndex;
  return true;
}

and then you see there is calls to:

static void signalInputEvent(void)
{
#if DEBUG_EVENTS
  printf("signalInputEvent\n");
#endif
  if (inputEventSemaIndex > 0)
    signalSemaphoreWithIndex(inputEventSemaIndex);
}


On win32 (platforms/win32/sqWin32Window.c)

There is a function which sets it up:

int ioSetInputSemaphore(int semaIndex) {
  inputSemaphoreIndex = semaIndex;
  return 1;
}

but there is no any code which signals it.

There's only a code which looks like:

 if(inputSemaphoreIndex) {
      recordMouseEvent(lastMessage, nrClicks);
      break;
 }

The fix is ultimately trivial, as you may guess:


sqInputEvent *sqNextEventPut(void) {
  sqInputEvent *evt;
  evt = eventBuffer + eventBufferPut;
  eventBufferPut = (eventBufferPut + 1) % MAX_EVENT_BUFFER;
  if (eventBufferGet == eventBufferPut) {
    /* buffer overflow; drop the last event */
    printf("WARNING: event buffer overflow\n");
    eventBufferGet = (eventBufferGet + 1) % MAX_EVENT_BUFFER;
  }
	
+++  if(inputSemaphoreIndex)
+++	  signalSemaphoreWithIndex(inputEventSemaIndex);

  return evt;
}




-- 
Best regards,
Igor Stasenko AKA sig.