Hi again,
Brandon Williams wrote:
> When working with worktrees the git directory is split into two part,
> the per-worktree gitdir and a commondir which contains things which are
> shared among all worktrees (like the object store). With this notion of
> having a split git directory, 557bd833b (git_path(): be aware of file
> relocation in $GIT_DIR) and c7b3a3d2f ($GIT_COMMON_DIR: a new
> environment variable) changed the way that 'git_path()' functioned so
> that paths would be adjusted if they referred to files or directories
> that are stored in the commondir or have been changed via an environment
> variable.
>
> One interesting problem with this is the index file as it is not shared
> across worktrees yet when asking for a path to a specific worktree's
> index it will be replaced with a path to the current worktree's index.
> In order to prevent this, teach 'adjuct_git_path' to replace the
> path to the index with the path recorded in a repository (which would be
> the current, active worktree) only when not asked to construct a path
> for a specific worktree.
>
> Signed-off-by: Brandon Williams <bmwill@xxxxxxxxxx>
> ---
> path.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
Digging more into it with your help, I ran into v2.5.0-rc0~143^2~34
and v2.11.0-rc0~15^2 (git-svn: "git worktree" awareness, 2016-10-14),
which uses this function:
- my $index = $ENV{GIT_INDEX_FILE} || "$ENV{GIT_DIR}/index";
+ my $index = command_oneline(qw(rev-parse --git-path index));
That rules out my hope of making git_path stop being aware of the index
at all.
That also made it a little clearer to me what is going on with this
function. I had previously misread !wt as meaning that git_dir is
not under worktrees/ (or in other words as !wt->id). Instead, it
means that the caller does not want to use some other work tree in
preference to git_dir.
With that piece in place, the patch starts making more sense to me.
When !wt, repo->index_file is going to have the same value as
getenv("GIT_INDEX_FILE") ?: buf->buf already, since repo->index_file
refers to the current work tree git dir's index file. When wt != NULL,
we don't want to use that file and have requested to grab the index
from a specific work tree git dir instead.
And patch 05/20 (environment: place key repository state in
the_repository) had no effect since no one calls worktree_git_path
with argument "index", nor with a user-specified path.
How about the following? I found it a little easier to understand.
-- >8 --
From: Brandon Williams <bmwill@xxxxxxxxxx>
Subject: worktree_git_path: do not let GIT_INDEX_FILE override path to index
git_path (and variants like strbuf_git_path) is designed to behave
like a convenience function that produces a string $GIT_DIR/<path>.
In the process, callers automatically get support for path relocation
variables like $GIT_OBJECT_DIRECTORY:
- git_path("index") is $GIT_INDEX_FILE when set
- git_path("info/grafts") is $GIT_GRAFTS_FILE when set
- git_path("objects/<foo>") is $GIT_OBJECT_DIRECTORY/<foo> when set
- git_path("hooks/<foo>") is <foo> under core.hookspath when set
- git_path("refs/<foo>") etc (see path.c::common_list) is relative
to $GIT_COMMON_DIR instead of $GIT_DIR
worktree_git_path, by comparison, is designed to resolve files in a
specific worktree's git dir and should not perform such relocation.
Do so by skipping the relocation step in worktree_git_path.
Fortunately no current callers of worktree_git_path pass such
arguments. Noticed due to an interaction between two patches under
review, one of which introduced such a caller:
* One made "git prune" check the index file in each worktree's git dir
(using worktree_git_path(wt, "index")) for objects not to prune,
triggering the unwanted relocation code by mistake and allowing
objects reachable from worktree indices to be pruned if
GIT_INDEX_FILE is set.
* The other simplified the relocation logic for index, info/grafts,
objects, and hooks to happen unconditionally instead of based on
whether environment or configuration variables are set, causing the
relocation to trigger even when GIT_INDEX_FILE is not set.
[jn: rewrote commit message; skipped all relocations instead of just
the index]
Change-Id: I2ba0a48a48b7e9a9c2e3ef97648cf53cb913bdd9
Signed-off-by: Brandon Williams <bmwill@xxxxxxxxxx>
Signed-off-by: Jonathan Nieder <jrnieder@xxxxxxxxx>
---
path.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/path.c b/path.c
index c1cb1cf62..4c3a27a8e 100644
--- a/path.c
+++ b/path.c
@@ -397,7 +397,8 @@ static void do_git_path(const struct worktree *wt, struct strbuf *buf,
strbuf_addch(buf, '/');
gitdir_len = buf->len;
strbuf_vaddf(buf, fmt, args);
- adjust_git_path(buf, gitdir_len);
+ if (!wt)
+ adjust_git_path(buf, gitdir_len);
strbuf_cleanup_path(buf);
}
--
2.13.1.611.g7e3b11ae1
