RFR: 8038296 sun/tools/jinfo/Basic.sh: java.io.IOException: Command failed in target VM

[Staffan Larsen]

On 25 mar 2014, at 13:46, Dmitry Samersoff <dmitry.samersoff at oracle.com> wrote:

> Staffan,
> 
> strtol() sets errno in two cases -
> 
> ERANGE if supplied value is less then LONG_MIN or greater than LONG_MAX
> EINVAL if supplied base is not supported.
> 
> if you pass probe == 'bla', strtol just return 0 and errno will not be
> set. So I'm not sure that check for errno has any value here.
> 
> One of possible way to check that supplied value is convertible to long is
> 
> char *eptr = probe;
> strtol(probe, (char **)&eptr, 10);
> if (eptr == probe) {
>  // we can't convert supplied value
>  return JNI_ERR;
> }

Yes, that will find problems when trying to convert something like ‘bla’. It will not capture the case where the input string is a too large (or small) value (value < LONG_MIN or > LONG_MAX). To capture both cases it looks like we need something like:

  errno = 0;
  char* end;
  int probe_typess = (int) strtol(probe, &end, 10);
  if (end == probe || errno) {
    return JNI_ERR;
  }


/Staffan

> 
> -Dmitry
> 
> 
> On 2014-03-25 11:31, Staffan Larsen wrote:
>> attachListener_solaris.cpp calls atoi() and then checks errno to see if any errors occurred. The problem is that atoi() does not set errno, so some old value of errno is checked which sometimes causes the function to fail.
>> 
>> The fix is to replace atoi() with strtol() which does set errno. But errno is only set if an error occurred and not set to 0 in case of success. Thus, I set errno to 0 before calling strtol() and check the value afterwards.
>> 
>> Verified with a JPRT run.
>> 
>> webrev: http://cr.openjdk.java.net/~sla/8038296/webrev.00/
>> bug: https://bugs.openjdk.java.net/browse/JDK-8038296
>> 
>> Thanks,
>> /Staffan
>> 
> 
> 
> -- 
> Dmitry Samersoff
> Oracle Java development team, Saint Petersburg, Russia
> * I would love to change the world, but they won't give me the sources.