Re: [PATCH 10/20] sparse-checkout: hold pattern list in index

>
> From: Derrick Stolee <dstolee@microsoft.com>
>
> As we modify the sparse-checkout definition, we perform index operations
> on a pattern_list that only exists in-memory. This allows easy backing
> out in case the index update fails.
>
> However, if the index write itself cares about the sparse-checkout
> pattern set, we need access to that in-memory copy. Place a pointer to
> a 'struct pattern_list' in the index so we can access this on-demand.
> This will be used in the next change which uses the sparse-checkout
> definition to filter out directories that are outsie the sparse cone.

>
> Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
> ---
>  builtin/sparse-checkout.c | 17 ++++++++++-------
>  cache.h                   |  2 ++
>  2 files changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/builtin/sparse-checkout.c b/builtin/sparse-checkout.c
> index 2306a9ad98e0..e00b82af727b 100644
> --- a/builtin/sparse-checkout.c
> +++ b/builtin/sparse-checkout.c
> @@ -110,6 +110,8 @@ static int update_working_directory(struct pattern_list *pl)
>         if (is_index_unborn(r->index))
>                 return UPDATE_SPARSITY_SUCCESS;
>
> +       r->index->sparse_checkout_patterns = pl;
> +
>         memset(&o, 0, sizeof(o));
>         o.verbose_update = isatty(2);
>         o.update = 1;
> @@ -138,6 +140,7 @@ static int update_working_directory(struct pattern_list *pl)
>         else
>                 rollback_lock_file(&lock_file);
>
> +       r->index->sparse_checkout_patterns = NULL;
>         return result;
>  }
>
> @@ -517,19 +520,18 @@ static int modify_pattern_list(int argc, const char **argv, enum modify_type m)
>  {
>         int result;
>         int changed_config = 0;
> -       struct pattern_list pl;
> -       memset(&pl, 0, sizeof(pl));
> +       struct pattern_list *pl = xcalloc(1, sizeof(*pl));
>
>         switch (m) {
>         case ADD:
>                 if (core_sparse_checkout_cone)
> -                       add_patterns_cone_mode(argc, argv, &pl);
> +                       add_patterns_cone_mode(argc, argv, pl);
>                 else
> -                       add_patterns_literal(argc, argv, &pl);
> +                       add_patterns_literal(argc, argv, pl);
>                 break;
>
>         case REPLACE:
> -               add_patterns_from_input(&pl, argc, argv);
> +               add_patterns_from_input(pl, argc, argv);
>                 break;
>         }
>
> @@ -539,12 +541,13 @@ static int modify_pattern_list(int argc, const char **argv, enum modify_type m)
>                 changed_config = 1;
>         }
>
> -       result = write_patterns_and_update(&pl);
> +       result = write_patterns_and_update(pl);
>
>         if (result && changed_config)
>                 set_config(MODE_NO_PATTERNS);
>
> -       clear_pattern_list(&pl);
> +       clear_pattern_list(pl);
> +       free(pl);
>         return result;
>  }
>
> diff --git a/cache.h b/cache.h
> index 1336c8d7435e..d75b352f38d3 100644
> --- a/cache.h
> +++ b/cache.h
> @@ -307,6 +307,7 @@ static inline unsigned int canon_mode(unsigned int mode)
>  struct split_index;
>  struct untracked_cache;
>  struct progress;
> +struct pattern_list;
>
>  struct index_state {
>         struct cache_entry **cache;
> @@ -332,6 +333,7 @@ struct index_state {
>         struct mem_pool *ce_mem_pool;
>         struct progress *progress;
>         struct repository *repo;
> +       struct pattern_list *sparse_checkout_patterns;
>  };
>
>  /* Name hashing */
> --
> gitgitgadget
>