[geos-devel] Thread safe error handling

[Sandro Santilli]

On Mon, Sep 09, 2013 at 12:37:02PM +0200, Pepijn Van Eeckhoudt wrote:
> On ma, 2013-09-09 at 10:49 +0200, Sandro Santilli wrote:
> > On Mon, Sep 09, 2013 at 09:43:51AM +0200, Pepijn Van Eeckhoudt wrote:
> > Can't we turn NOTICE_MESSAGE and ERROR_MESSAGE into variadic methods
> > of the GEOSContextHandlerInternal class ? We could print to a string
> > and always pass a single string to the user-provided function, using
> > an hardcoded "%s" format for it.
>
> Not sure if I understand this correctly. Do you mean you would do the
> actual formatting on the geos side and pass the formatted string as
> 'fmt' then? That would work if you're ok with the subtle behavioural
> change. Seems unlikely that anyone would count on the exact contents of
> 'fmt' and the parameter list, but you never know...

I'd pass "%s" as the 'fmt' arg, and a pointer to a geos-owned memory
space as the only argument. No client should be expecting anything
from those calls, except they'd be composed by a printf-like format
and a variable list of arguments which work fine with that format.

> Memory allocation for the formatted string shifts to geos then as well;
> do you think that's an issue?

I don't see any issue there, clients would still need to re-print
the returned string. Only, we'll need a buffer for messages in each
GEOSContextHandlerInternal instance.

--strk;