Re: [PATCH v2 4/5] config: add git_configset_alloc() and git_configset_clear_and_free()

[phillip.wood123@gmail.com]

Hi Josh

On 12/08/2024 22:39, Josh Steadmon wrote:
> On 2024.08.12 10:10, Phillip Wood wrote:
>> Hi Josh
>>
>> Do we really need to add this code to config.c rather than handling it in
>> the wrapper layer in the next patch?
>>
>> Looking ahead I wonder how useful it is to users of the library to separate
>> out allocation from initialization. A function that allocates and
>> initializes a configset would be more convenient and harder to misuse.
>> Calling release functions *_free() rather than *_clear_and_free() would be
>> more convenient as well. I also noticed that the data types are not
>> namespaced when they are exported. So perhaps we could drop this patch and
>> add the following to the next patch.
>>
>> /*
>>   * Namespace data types as well as functions and ensure consistent
>>   * naming of data types and the functions that operate on them.
>>   */
>> struct libgit_configset {
>> 	struct config_set set;
>> };
>>
>> struct libgit_configset *libgit_configset_new() {
>> 	struct libgit_configset *set = xmalloc(sizeof(*set));
>>
>> 	git_configset_init(&set->set);
>> 	return set;
>> }
>>
>> void libgit_configset_free(struct libgit_configset *set) {
>> 	git_configset_clear(&set->set);
>> 	free(set);
>> }
> 
> Hmmm I see your point, but I am also hoping to keep the symbol export
> shim as small as possible, so that we can try to autogenerate it rather
> than add entries by hand.

That's a nice aim - how do you plan to address namespacing data types 
with that approach? The autogenerator would need to know "struct 
config_set" wants to be wrapped as "struct libgit_configset" to ensure 
we end up with consistent naming for the data type and its functions. 
We'd also still want to make sure we end up with an ergonomic api which 
means one function to allocate and initialize each data type, not 
separate functions for allocation and initialization.

> However, if people feel strongly that we don't
> want to add helper functions like *_alloc() or *_free() for types that don't
> already have them upstream, perhaps we can just put them in a separate
> rust-helpers.c file or something.

If we're not using them upstream they're just clutter as far as git is 
concerned. Having said that if you get the autogeneration working well 
so the output is usable without a lot of manual tweaking I can see an 
argument for having these functions upstream.

Best Wishes

Phillip