Re: [PATCH 04/12] environment: move access to "core.bigFileThreshold" into repo settings

> The "core.bigFileThreshold" setting is stored in a global variable and
> populated via `git_default_core_config()`. This may cause issues in
> the case where one is handling multiple different repositories in a
> single process with different values for that config key, as we may or
> may not see the correct value in that case. Furthermore, global state
> blocks our path towards libification.
> 
> Refactor the code so that we instead store the value in `struct
> repo_settings`, where the value is computed as-needed and cached.
> 
> Signed-off-by: Patrick Steinhardt <ps@pks.im>
> ---

> diff --git a/repo-settings.c b/repo-settings.c
> index 67e9cfd2e63..4129f8fb2b4 100644
> --- a/repo-settings.c
> +++ b/repo-settings.c
> @@ -20,6 +20,13 @@ static void repo_cfg_int(struct repository *r, const char *key, int *dest,
>  		*dest = def;
>  }
>  
> +static void repo_cfg_ulong(struct repository *r, const char *key, unsigned long *dest,
> +			   unsigned long def)
> +{
> +	if (repo_config_get_ulong(r, key, dest))
> +		*dest = def;
> +}
> +
>  void prepare_repo_settings(struct repository *r)
>  {
>  	int experimental;
> @@ -151,6 +158,19 @@ void repo_settings_clear(struct repository *r)
>  	r->settings = empty;
>  }
>  
> +unsigned long repo_settings_get_big_file_threshold(struct repository *repo)
> +{
> +	if (!repo->settings.big_file_threshold)
> +		repo_cfg_ulong(repo, "core.bigfilethreshold",
> +			       &repo->settings.big_file_threshold, 512 * 1024 * 1024);
> +	return repo->settings.big_file_threshold;
> +}

> +
> +void repo_settings_set_big_file_threshold(struct repository *repo, unsigned long value)
> +{
> +	repo->settings.big_file_threshold = value;
> +}
> +
>  enum log_refs_config repo_settings_get_log_all_ref_updates(struct repository *repo)
>  {
>  	const char *value;
> diff --git a/repo-settings.h b/repo-settings.h
> index ddc11967e01..2bf24b25973 100644
> --- a/repo-settings.h
> +++ b/repo-settings.h
> @@ -64,6 +64,7 @@ struct repo_settings {
>  	size_t delta_base_cache_limit;
>  	size_t packed_git_window_size;
>  	size_t packed_git_limit;
> +	unsigned long big_file_threshold;
>  
>  	char *hooks_path;
>  };
> @@ -88,6 +89,10 @@ int repo_settings_get_warn_ambiguous_refs(struct repository *repo);
>  /* Read the value for "core.hooksPath". */
>  const char *repo_settings_get_hooks_path(struct repository *repo);
>  
> +/* Read and set the value for "core.bigFileThreshold". */
> +unsigned long repo_settings_get_big_file_threshold(struct repository *repo);
> +void repo_settings_set_big_file_threshold(struct repository *repo, unsigned long value);
> +
>  /* Read, set or reset the value for "core.sharedRepository". */
>  int repo_settings_get_shared_repository(struct repository *repo);
>  void repo_settings_set_shared_repository(struct repository *repo, int value);
> diff --git a/streaming.c b/streaming.c
> index 38839511afc..018b794d252 100644
> --- a/streaming.c
> +++ b/streaming.c
> @@ -431,7 +431,8 @@ static int istream_source(struct git_istream *st,
>  		st->open = open_istream_loose;
>  		return 0;
>  	case OI_PACKED:
> -		if (!oi.u.packed.is_delta && big_file_threshold < size) {
> +		if (!oi.u.packed.is_delta &&
> +		    repo_settings_get_big_file_threshold(the_repository) < size) {
>  			st->u.in_pack.pack = oi.u.packed.pack;
>  			st->u.in_pack.pos = oi.u.packed.offset;
>  			st->open = open_istream_pack_non_delta;
> diff --git a/t/t1050-large.sh b/t/t1050-large.sh
> index c71932b0242..5be273611ad 100755
> --- a/t/t1050-large.sh
> +++ b/t/t1050-large.sh
> @@ -6,7 +6,8 @@ test_description='adding and checking out large blobs'
>  . ./test-lib.sh
>  
>  test_expect_success 'core.bigFileThreshold must be non-negative' '
> -	test_must_fail git -c core.bigFileThreshold=-1 rev-parse >out 2>err &&
> +	: >input &&
> +	test_must_fail git -c core.bigFileThreshold=-1 hash-object input >out 2>err &&
>  	grep "bad numeric config value" err &&
>  	test_must_be_empty out
>  '