Re: [PATCH 07/10] unpack-trees API: rename clear_unpack_trees_porcelain()

[Phillip Wood <phillip.wood123@xxxxxxxxx>]

Hi Ævar

On 04/10/2021 01:46, Ævar Arnfjörð Bjarmason wrote:
> Since a preceding commit we've been using
> clear_unpack_trees_porcelain() to call dir_clear(). So it's no longer
> a function that corresponds to setup_unpack_trees_porcelain(), as it
> was when it was added in 1c41d2805e4 (unpack_trees_options: free
> messages when done, 2018-05-21).
>
> Instead it's similar to strbuf_release() and other similar generic
> "free" functions. Let's rename it to avoid any future confusion on the
> topic.
>
> Let's also update the API documentation for it to note this, and to
> cover e.g. the code added around update_sparsity() in
> 4ee5d50fc39 (sparse-checkout: use improved unpack_trees porcelain
> messages, 2020-03-27).
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>
> ---
>   builtin/checkout.c        | 2 +-
>   builtin/sparse-checkout.c | 2 +-
>   merge-ort.c               | 2 +-
>   merge-recursive.c         | 2 +-
>   merge.c                   | 4 ++--
>   reset.c                   | 2 +-

I was expecting to see sequencer.c here, but it appears it does not call 
clear_unpack_trees_porcelain() to free the memory allocated with 
setup_unpack_trees_porcelain(). If you're interested in fixing memory 
leaks from unpack trees it might be worth checking that all the calls to 
setup_unpack_trees_porcelain() have a matching call to 
clear_unpack_trees_porcelain().

Best Wishes

Phillip

>   unpack-trees.c            | 2 +-
>   unpack-trees.h            | 8 +++++---
>   8 files changed, 13 insertions(+), 11 deletions(-)
>
> diff --git a/builtin/checkout.c b/builtin/checkout.c
> index d4b88affba7..482d17676a0 100644
> --- a/builtin/checkout.c
> +++ b/builtin/checkout.c
> @@ -757,7 +757,7 @@ static int merge_working_tree(const struct checkout_opts *opts,
>   		init_tree_desc(&trees[1], tree->buffer, tree->size);
>   
>   		ret = unpack_trees(2, trees, &topts);
> -		clear_unpack_trees_porcelain(&topts);
> +		unpack_trees_options_release(&topts);
>   		if (ret == -1) {
>   			/*
>   			 * Unpack couldn't do a trivial merge; either
> diff --git a/builtin/sparse-checkout.c b/builtin/sparse-checkout.c
> index 4c3c29fb580..b1221fd01d3 100644
> --- a/builtin/sparse-checkout.c
> +++ b/builtin/sparse-checkout.c
> @@ -219,7 +219,7 @@ static int update_working_directory(struct pattern_list *pl)
>   
>   	setup_unpack_trees_porcelain(&o, "sparse-checkout");
>   	result = update_sparsity(&o);
> -	clear_unpack_trees_porcelain(&o);
> +	unpack_trees_options_release(&o);
>   
>   	if (result == UPDATE_SPARSITY_WARNINGS)
>   		/*
> diff --git a/merge-ort.c b/merge-ort.c
> index e526b78b88d..0a5937364c9 100644
> --- a/merge-ort.c
> +++ b/merge-ort.c
> @@ -4054,7 +4054,7 @@ static int checkout(struct merge_options *opt,
>   	init_tree_desc(&trees[1], next->buffer, next->size);
>   
>   	ret = unpack_trees(2, trees, &unpack_opts);
> -	clear_unpack_trees_porcelain(&unpack_opts);
> +	unpack_trees_options_release(&unpack_opts);
>   	return ret;
>   }
>   
> diff --git a/merge-recursive.c b/merge-recursive.c
> index a77f66b006c..316cb2ca907 100644
> --- a/merge-recursive.c
> +++ b/merge-recursive.c
> @@ -441,7 +441,7 @@ static int unpack_trees_start(struct merge_options *opt,
>   static void unpack_trees_finish(struct merge_options *opt)
>   {
>   	discard_index(&opt->priv->orig_index);
> -	clear_unpack_trees_porcelain(&opt->priv->unpack_opts);
> +	unpack_trees_options_release(&opt->priv->unpack_opts);
>   	unpack_trees_options_init(&opt->priv->unpack_opts);
>   }
>   
> diff --git a/merge.c b/merge.c
> index 9cb32990dd9..2f618425aff 100644
> --- a/merge.c
> +++ b/merge.c
> @@ -95,10 +95,10 @@ int checkout_fast_forward(struct repository *r,
>   
>   	if (unpack_trees(nr_trees, t, &opts)) {
>   		rollback_lock_file(&lock_file);
> -		clear_unpack_trees_porcelain(&opts);
> +		unpack_trees_options_release(&opts);
>   		return -1;
>   	}
> -	clear_unpack_trees_porcelain(&opts);
> +	unpack_trees_options_release(&opts);
>   
>   	if (write_locked_index(r->index, &lock_file, COMMIT_LOCK))
>   		return error(_("unable to write new index file"));
> diff --git a/reset.c b/reset.c
> index d13984ab781..f4bf3fbfac0 100644
> --- a/reset.c
> +++ b/reset.c
> @@ -133,7 +133,7 @@ int reset_head(struct repository *r, struct object_id *oid, const char *action,
>   leave_reset_head:
>   	strbuf_release(&msg);
>   	rollback_lock_file(&lock);
> -	clear_unpack_trees_porcelain(&unpack_tree_opts);
> +	unpack_trees_options_release(&unpack_tree_opts);
>   	while (nr)
>   		free((void *)desc[--nr].buffer);
>   	return ret;
> diff --git a/unpack-trees.c b/unpack-trees.c
> index e7365322e82..bea598c9ece 100644
> --- a/unpack-trees.c
> +++ b/unpack-trees.c
> @@ -193,7 +193,7 @@ void unpack_trees_options_init(struct unpack_trees_options *o)
>   	memcpy(o, &blank, sizeof(*o));
>   }
>   
> -void clear_unpack_trees_porcelain(struct unpack_trees_options *opts)
> +void unpack_trees_options_release(struct unpack_trees_options *opts)
>   {
>   	strvec_clear(&opts->msgs_to_free);
>   	dir_clear(&opts->dir);
> diff --git a/unpack-trees.h b/unpack-trees.h
> index 40c4841748d..a8d1f083b33 100644
> --- a/unpack-trees.h
> +++ b/unpack-trees.h
> @@ -41,10 +41,12 @@ enum unpack_trees_error_types {
>   void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
>   				  const char *cmd);
>   
> -/*
> - * Frees resources allocated by setup_unpack_trees_porcelain().
> +/**
> + * Frees resources allocated by function that take the "struct
> + * unpack_trees_options". Always call this after using unpack_trees(),
> + * update_sparsity() etc.
>    */
> -void clear_unpack_trees_porcelain(struct unpack_trees_options *opts);
> +void unpack_trees_options_release(struct unpack_trees_options *opts);
>   
>   struct unpack_trees_options {
>   	unsigned int reset,