Re: [PATCH 1/4] wt-status: read HEAD and ORIG_HEAD via the refdb
From: Taylor Blau <hidden>
Date: 2023-11-29 21:45:02
On Wed, Nov 29, 2023 at 09:14:12AM +0100, Patrick Steinhardt wrote:
quoted hunk ↗ jump to hunk
We read both the HEAD and ORIG_HEAD references directly from the filesystem in order to figure out whether we're currently splitting a commit. If both of the following are true: - HEAD points to the same object as "rebase-merge/amend". - ORIG_HEAD points to the same object as "rebase-merge/orig-head". Then we are currently splitting commits. 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. 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. Signed-off-by: Patrick Steinhardt <redacted> --- 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))
Switching to read_ref_full() here is going to have some slightly different behavior than just reading out the contents of "$GIT_DIR/HEAD", but I think that it should be OK. Before we would not have complained, if, for example, the contents of "$GIT_DIR/HEAD" were malformed, but now we will. I think that's OK, especially given that if that file is bogus, we'll have other problems before we get here ;-). Are there any other gotchas that we should be thinking about?
+ return 0;
+
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))I did a double take at these strcmp(oid_to_hex(...)) calls, but I think that they are the best that we can do given that we're still reading the contents of "rebase-merge/amend" and "rebase-merge/orig-head" directly. I suppose we could go the other way and turn their contents into object_ids and then use oidcmp(), but it doesn't seem worth it IMHO. Thanks, Taylor