svn commit: r245259 - projects/utrace2

[Alfred Perlstein]

On 1/14/13 2:01 PM, John Baldwin wrote:
> On Monday, January 14, 2013 1:44:28 pm Alfred Perlstein wrote:
>> I think we are basically in agreement, however we differ on the following two points, whereas now I think we only differ on a single point.
>>
>> 1) belief that a 4 character string signature is superior to a protocol/version tuple.
>>
>>    After looking at the code and thinking about this quite a bit, I agree with you that string based namespace is nicer, however I think we need the
> following changes:
>>    a) define the system namespace to have "_" preceding the trace name.  so RTLD -> _RTL
>>    b) or maybe we need another few characters? 6 or 8 so that it can still be nice. so "_RTL" -> "_RTLD\0\0\0", "_MALLOC\0"
>>    c) we add a version field after the character string.
>>    d) we create a mechanism for requesting a utrace allocation namespace somewhere (/usr/share/utrace/allocations.txt) where vendors can allocate
> strings.
>> 2) you believe that filtering this all through utrace(2) is OK.  I would prefer that we leave utrace(2) alone and move forward with utrace2(2) to
> leave behind all the unformatted data we used to have.  I would like to leave utrace(2) in the system and add utrace2(2) for new consumers.
>> What do you think?
>>
>> My end goal is to make this something that more users can grab and use for a quick and handy debug tool and to actually build on this somewhat,
> (libutrace) what we have now (unstructured globs of whatever) does not work.
>
> I disagree with this last assertion.  On what basis do you claim that what we
> have now does not work?  Do you have any specific examples besides
> hypothetical cases?  I fail to see how utrace() in its current form is not
> already useful, and I've yet to see a convincing argument from you that it is
> not.
>
#include <stdio.h>
#include <stdlib.h>

int
main(void)
{
         void *ptr = 0x52544c44;

         realloc(ptr, 200);
}





-Alfred