Re: [PATCH v2 1/4] wt-status: read HEAD and ORIG_HEAD via the refdb
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Dec 12, 2023, 20:24 UTC
- Message-ID
- <xmqqle9zqidj.fsf@gitster.g>
- In-Reply-To
- <1db3eb3945432964aabe1c559db4c3ac251e83fd.1702365291.git.ps@pks.im>
Patrick Steinhardt <ps@pks.im> writes:
> The current code only works by chance because we only have a single > reference backend implementation. Refactor it to instead read both refs > via the refdb layer so that we'll also be compatible with alternate > reference backends.
"via the refdb" -> "via the refs API" or something here and on the title, and possibly elsewhere in the proposed log messages and in-code comments in patches in this series, as I've never seen a word "refdb" used in the context of this project.
I agree it is bad manners to be intimate with the implementation details of the how files-backend stores HEAD and ORIG_HEAD.
> Note that we pass `RESOLVE_REF_NO_RECURSE` to `read_ref_full()`. This is > because we didn't resolve symrefs before either, and in practice none of > the refs in "rebase-merge/" would be symbolic. We thus don't want to > resolve symrefs with the new code either to retain the old behaviour.
Good to see a rewrite being careful like this.
Show 27 quoted lines
> Signed-off-by: Patrick Steinhardt <ps@pks.im>
> ---
> wt-status.c | 17 +++++++++--------
> 1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/wt-status.c b/wt-status.c
> index 9f45bf6949..fe9e590b80 100644
> --- a/wt-status.c
> +++ b/wt-status.c
> @@ -1295,26 +1295,27 @@ static char *read_line_from_git_path(const char *filename)
> static int split_commit_in_progress(struct wt_status *s)
> {
> int split_in_progress = 0;
> - char *head, *orig_head, *rebase_amend, *rebase_orig_head;
> + struct object_id head_oid, orig_head_oid;
> + char *rebase_amend, *rebase_orig_head;
>
> if ((!s->amend && !s->nowarn && !s->workdir_dirty) ||
> !s->branch || strcmp(s->branch, "HEAD"))
> return 0;
>
> - head = read_line_from_git_path("HEAD");
> - orig_head = read_line_from_git_path("ORIG_HEAD");
> + if (read_ref_full("HEAD", RESOLVE_REF_NO_RECURSE, &head_oid, NULL) ||
> + read_ref_full("ORIG_HEAD", RESOLVE_REF_NO_RECURSE, &orig_head_oid, NULL))
> + return 0;
> +This made me wonder if we have changed behaviour when on an unborn branch. In such a case, the original most likely would have read "ref: blah" in "head" and compared it with "rebase_amend", which would be a good way to ensure they would not match. I would not know offhand what the updated code would do, but head_oid would be uninitialized in such a case, so ...?
Show 17 quoted lines
> rebase_amend = read_line_from_git_path("rebase-merge/amend");
> rebase_orig_head = read_line_from_git_path("rebase-merge/orig-head");
>
> - if (!head || !orig_head || !rebase_amend || !rebase_orig_head)
> + if (!rebase_amend || !rebase_orig_head)
> ; /* fall through, no split in progress */
> else if (!strcmp(rebase_amend, rebase_orig_head))
> - split_in_progress = !!strcmp(head, rebase_amend);
> - else if (strcmp(orig_head, rebase_orig_head))
> + split_in_progress = !!strcmp(oid_to_hex(&head_oid), rebase_amend);
> + else if (strcmp(oid_to_hex(&orig_head_oid), rebase_orig_head))
> split_in_progress = 1;
>
> - free(head);
> - free(orig_head);
> free(rebase_amend);
> free(rebase_orig_head);