Re: libwapcaplet - memory leak?

On 26/02/2013 10:17, Daniel Silverstone wrote:
> On Tue, Feb 26, 2013 at 07:05:05AM +0000, John-Mark Bell wrote:
>> On Mon, 2013-02-25 at 20:10 +0000, Chris Young wrote:
>>> I must be msising something, but libwapcaplet allocates a "bucket" in
>>> lwc__initialise(). As far as I can tell, this is never freed - as
>>> there is no lwc__finalise or equivalent function?
>>
>> Correct -- this is expected. There's no safe way to do this without
>> adding a context to the lwc API. That introduces a significant amount of
>> pain in clients (as they have to pass the context around internally,
>> which is problematic when you have multiple things using it. Thus, the
>> root hash bucket is leaked, instead.
>>
>> I guess we could free the bucket when there are no strings left in it,
>> however. Daniel: any thoughts?
>
> It seems a tad silly to add a check to *every* unref to decide if we can free
> the root bucket. Esp. given that with all the libs in use, that root bucket
> will only ever empty fully immediately before exit.

Or rather actually (hopefully) before unloading the library.

At least on BeOS we can in theory include NetSurf as a replicant, where
the binary is dlopen()ed and dlclosed() when removed, so using atexit()
would cause quite some trouble there.

Instead there are almost-standard hooks for use in libraries, though the
names differ between OSes they are usually always usable.
On ELF-based things it's usually _fini() though the dlopen man on linux
mentions them as deprecated in favor of __attribute__((destructor)).

François.