[PATCH] Change module interface to pass in a TALLOC_CTX pointer.

Jeremy Allison jra at samba.org
Fri Apr 21 03:01:41 UTC 2017

Currently the initialization function of all our modules are called with a
function signature of:

NTSTATUS XXX_init(void)

The following patch changes this to be:


instead. The patch (for 4.7.x naturally) merely changes
the definition of the initialization functions and their
callers, and implements *no* logic changes (all of the changed
callers in this patch pass NULL in as the new TALLOC_CTX *ctx
and the modules ignore it).

As it's a change to the module interfaces, I have also
incremented the version numbers for all loadable modules,
and added text to the WHATSNEW and to the module documentation.

The reason I want this change is that currently many modules
do something like:

NTSTATUS XXX_init(void)

and the called function looks like:

void call_register_function(...params...)
	backend = talloc(talloc_autofree_context(), .... );

Essentially the modules don't get access to a long-lived
talloc context from their caller so end up using the global
talloc_autofree_context() so they look cleaner when run under
valgrind (i.e. at least someone frees this stuff on exit).

This is a nasty, lazy way of memory management and I really
want the calling program to hand them down a long-lived
talloc context (usually initialized in the main() function
of the program) and manage doing the talloc_free() just
before doing the exit itself.

I'd appreciate people looking this over to ensure I've
changed all the relevent version numbers, ABI numbers etc.

It passes a full autobuild make test. Once it gets in I
can start fixing the underlying memory management by
passing in a real talloc context that the modules can
use for their long-term initialization use instead of

Let me know what you think. It looks a bigger change
than it is, most of it is pure boilerplate changes.


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