Re: [PATCH v3 1/5] [GSOC] ref-filter: add obj-type check in grab contents

[Jacob Keller <jacob.keller@gmail.com>]

On Sat, Jul 24, 2021 at 7:14 AM ZheNing Hu via GitGitGadget
<gitgitgadget@gmail.com> wrote:
>
> From: ZheNing Hu <adlternative@gmail.com>
>
> Only tag and commit objects use `grab_sub_body_contents()` to grab
> object contents in the current codebase.  We want to teach the
> function to also handle blobs and trees to get their raw data,
> without parsing a blob (whose contents looks like a commit or a tag)
> incorrectly as a commit or a tag. So it's needed to pass a
> `struct expand_data *data` instread of only `void *buf` to both
> `grab_sub_body_contents()` and `grab_values()` to be able to check
> the object type.
>
> Skip the block of code that is specific to handling commits and tags
> early when the given object is of a wrong type to help later
> addition to handle other types of objects in this function.
>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Hariom Verma <hariom18599@gmail.com>
> Helped-by: Junio C Hamano <gitster@pobox.com>
> Signed-off-by: ZheNing Hu <adlternative@gmail.com>
> ---

Nice. The addition of changing the type made sense and is spelled out nicely.

Reviewed-by: Jacob Keller <jacob.keller@gmail.com>

>  ref-filter.c | 24 +++++++++++++++---------
>  1 file changed, 15 insertions(+), 9 deletions(-)
>
> diff --git a/ref-filter.c b/ref-filter.c
> index 4db0e40ff4c..5cee6512fba 100644
> --- a/ref-filter.c
> +++ b/ref-filter.c
> @@ -1356,11 +1356,12 @@ static void append_lines(struct strbuf *out, const char *buf, unsigned long size
>  }
>
>  /* See grab_values */
> -static void grab_sub_body_contents(struct atom_value *val, int deref, void *buf)
> +static void grab_sub_body_contents(struct atom_value *val, int deref, struct expand_data *data)
>  {
>         int i;
>         const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;
>         size_t sublen = 0, bodylen = 0, nonsiglen = 0, siglen = 0;
> +       void *buf = data->content;
>
>         for (i = 0; i < used_atom_cnt; i++) {
>                 struct used_atom *atom = &used_atom[i];
> @@ -1371,10 +1372,13 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, void *buf)
>                         continue;
>                 if (deref)
>                         name++;
> -               if (strcmp(name, "body") &&
> -                   !starts_with(name, "subject") &&
> -                   !starts_with(name, "trailers") &&
> -                   !starts_with(name, "contents"))
> +
> +               if ((data->type != OBJ_TAG &&
> +                    data->type != OBJ_COMMIT) ||
> +                   (strcmp(name, "body") &&
> +                    !starts_with(name, "subject") &&
> +                    !starts_with(name, "trailers") &&
> +                    !starts_with(name, "contents")))
>                         continue;
>                 if (!subpos)
>                         find_subpos(buf,
> @@ -1438,17 +1442,19 @@ static void fill_missing_values(struct atom_value *val)
>   * pointed at by the ref itself; otherwise it is the object the
>   * ref (which is a tag) refers to.
>   */
> -static void grab_values(struct atom_value *val, int deref, struct object *obj, void *buf)
> +static void grab_values(struct atom_value *val, int deref, struct object *obj, struct expand_data *data)
>  {
> +       void *buf = data->content;
> +
>         switch (obj->type) {
>         case OBJ_TAG:
>                 grab_tag_values(val, deref, obj);
> -               grab_sub_body_contents(val, deref, buf);
> +               grab_sub_body_contents(val, deref, data);
>                 grab_person("tagger", val, deref, buf);
>                 break;
>         case OBJ_COMMIT:
>                 grab_commit_values(val, deref, obj);
> -               grab_sub_body_contents(val, deref, buf);
> +               grab_sub_body_contents(val, deref, data);
>                 grab_person("author", val, deref, buf);
>                 grab_person("committer", val, deref, buf);
>                 break;
> @@ -1678,7 +1684,7 @@ static int get_object(struct ref_array_item *ref, int deref, struct object **obj
>                         return strbuf_addf_ret(err, -1, _("parse_object_buffer failed on %s for %s"),
>                                                oid_to_hex(&oi->oid), ref->refname);
>                 }
> -               grab_values(ref->value, deref, *obj, oi->content);
> +               grab_values(ref->value, deref, *obj, oi);
>         }
>
>         grab_common_values(ref->value, deref, oi);
> --
> gitgitgadget
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