Refactoring src/ausearch-report.c:output_interpreted_node()

[Burn Alting]

On Wed, 2014-10-01 at 17:24 -0400, Steve Grubb wrote:
> On Wednesday, October 01, 2014 05:19:39 PM Steve Grubb wrote:
> > On Thursday, October 02, 2014 07:08:13 AM Burn Alting wrote:
> > > On Wed, 2014-10-01 at 14:54 -0400, Steve Grubb wrote:
> > > > > I am uncertain what effect of accepting this additional format would
> > > > > have when adding rules to the running audit system - i.e.
> > > > > audit_name_to_msg_type() is called by autrace/auditctl when parsing
> > > > > rules (ie the msgtype field name).
> > > > 
> > > > I think ausearch-report.c might be the place that needs updating.
> > > 
> > > So, could we modify output_interpreted_node() to no longer re-parse the
> > > 
> > >    [node=<node>] type=<type> msg=audit(<epochsecs>.<msecs>:<serial>)
> > > 
> > > header and pass both the lnode and llist->e which has this data already
> > > as the code
> > > 
> > >           if (num == -1) {
> > >           
> > >               // see if we are older and wiser now.
> > >               bptr = strchr(str, '[');
> > >               if (bptr && bptr < ptr) {
> > >                   char *eptr;
> > >                   bptr++;
> > >                   eptr = strchr(bptr, ']');
> > >                   if (eptr) {
> > >                        *eptr = 0;
> > >                        errno = 0;
> > >                        num = strtoul(bptr, NULL, 10);
> > >                        *eptr = ']';
> > >                        if (errno)
> > >                            num = -1;
> > >                   }
> > >                }
> > >          }
> > > 
> > > which parses for
> > > 
> > >     type=.*[n].*
> > > 
> > > is no longer needed as we don't have that format any more?
> > 
> > That is a very loose check for UNKNOWN[####]. If you see a performance
> > improvement by refactoring this function, please send a patch. The output
> > needs to be identical to the old way.
> 
> Note that this section of code is on the "slow path". The value of interest 
> extraction and matching is the performance critical area. Once an event is 
> selected for output, the tty scrolling and buffering probably dominate the 
> speed. So, I would take a patch to optimize this, but I don't expect it to 
> make a big difference.
> 
> -Steve

I'm not really after a performance gain, but rather, positioning
output_interpreted_node() to possibly support multiple formats for
output [see my other posts].


Rgds