initial gencache implementation

[Rafal Szczesniak]

On Fri, Sep 06, 2002 at 10:17:19AM +1000, Tim Potter wrote:
> On Thu, Sep 05, 2002 at 12:15:36PM +0200, Rafal Szczesniak wrote:
> 
> > This is first implementation of caching mechanism. It includes
> > both lib/gencache.c code and utils/net_cache.c as command-line
> > control/testing tool.
> > 
> > comments are welcome
> 
> Rafal, that looks pretty good.  Since you ask, I do have a few comments.
> (-:

I'm glad to hear that :)

> You assume that any cached data will be in null terminated string format
> which is not always the case.  

I assume that on gencache base we can implement any higher-level
caching function like namecache. Then, it's up to such implementation
how to 'pack' the structures into string form. Null terminated string
format is much easier to watch with 'net cache list' command. Thus
we have comfortable and easy mean to watch what's in the cache file.

> This is just my personal opinion but I would prefer for gencache_set to
> crash

To avoid mistake, I should ask what exactly do you mean by 'crash' ?

> if you pass it a NULL pointer for the key or value parameter.
> Returning false in this case only hides the error until further along 
> in the execution path by which time it will be more difficult to track 
> down the original error.

Good point. Just explain me this 'crash' thing.

> Some other minor things:
> 
> 	- memleak of cache_fname in gencache_init
> 	- memleak of keybuf.dptr in gencache_set

Thank you. The latter was already fixed - I just forgot to send fixed
version :)

> I don't think you need to strdup the key before passing it to tdb_fetch
> in gencache_set.  You can just use the passed in parameter.

I thought about that but unfortunatelly tdb_store doesn't have const
args, so compiler complains about passing pointers to non-const args.
I think tdb_store should have const-ed args (since it copies them anyway),
but it's quite other topic.



-- 
cheers,
+------------------------------------------------------------+
|Rafal 'Mimir' Szczesniak <mimir at diament.ists.pwr.wroc.pl>   |
|*BSD, GNU/Linux and Samba                                  /
|__________________________________________________________/