From: Stefan Beller <sbeller@google.com>
To: Michael Haggerty <mhagger@alum.mit.edu>
Cc: "Junio C Hamano" <gitster@pobox.com>, "Jeff King" <peff@peff.net>,
"Ævar Arnfjörð Bjarmason" <avarab@gmail.com>,
"Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>,
"David Turner" <novalis@novalis.org>,
"git@vger.kernel.org" <git@vger.kernel.org>
Subject: Re: [PATCH v2 01/20] get_ref_dir(): don't call read_loose_refs() for "refs/bisect"
Date: Fri, 31 Mar 2017 10:18:26 -0700 [thread overview]
Message-ID: <CAGZ79kZ9uGjhN5n8YAdUh2xqDMxTmmfsa7rCEWMk-Bsp5uxncg@mail.gmail.com> (raw)
In-Reply-To: <53e0eed5e13a04f502dcaeda83b2cbb3035f1396.1490966385.git.mhagger@alum.mit.edu>
On Fri, Mar 31, 2017 at 7:10 AM, Michael Haggerty <mhagger@alum.mit.edu> wrote:
> Since references under "refs/bisect/" are per-worktree, they have to
> be sought in the worktree rather than in the main repository. But
> since loose references are found by traversing directories, the
> reference iterator won't even get the idea to look for a
> "refs/bisect/" directory in the worktree if there is not a directory
> with that name in the main repository. Thus `get_ref_dir()` manually
> inserts a dir_entry for "refs/bisect/" whenever it reads the entry for
> "refs/".
>
> The current code then immediately calls `read_loose_refs()` on that
> directory. But since the dir_entry is created with its `incomplete`
> flag set, any traversal that gets to this point will read the
> directory automatically. So there is no need to call
> `read_loose_refs()` explicitly; the lazy mechanism suffices.
>
> And in fact, the attempt to `read_loose_refs()` was broken anyway.
> That function needs its `dirname` argument to have a trailing `/`
> character, but the invocation here was passing it "refs/bisect"
> without a trailing slash. So `read_loose_refs()` would read
> `$GIT_DIR/refs/bisect" correctly, but if it found an entry "foo" in
> that directory, it would try to read "$GIT_DIR/refs/bisectfoo".
> Normally it wouldn't find anything at that path, but the failure was
> canceled out because `get_ref_dir()` *also* forgot to reset the
> `REF_INCOMPLETE` bit on the dir_entry. So the read was attempted again
> when it was accessed, via the lazy mechanism, and this time the read
> was done correctly.
With all this retry logic going on, it is hard to add a test demonstrating
this is correct now. The description makes sense though.
Thanks,
Stefan
next prev parent reply other threads:[~2017-03-31 17:18 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-31 14:10 [PATCH v2 00/20] Separate `ref_cache` into a separate module Michael Haggerty
2017-03-31 14:10 ` [PATCH v2 01/20] get_ref_dir(): don't call read_loose_refs() for "refs/bisect" Michael Haggerty
2017-03-31 17:18 ` Stefan Beller [this message]
2017-03-31 14:11 ` [PATCH v2 02/20] refs_read_raw_ref(): new function Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 03/20] refs_ref_iterator_begin(): " Michael Haggerty
2017-04-07 10:57 ` Duy Nguyen
2017-04-16 4:39 ` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 04/20] refs_verify_refname_available(): implement once for all backends Michael Haggerty
2017-04-07 11:20 ` Duy Nguyen
2017-04-16 4:44 ` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 05/20] refs_verify_refname_available(): use function in more places Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 06/20] ref-cache: rename `add_ref()` to `add_ref_entry()` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 07/20] ref-cache: rename `find_ref()` to `find_ref_entry()` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 08/20] ref-cache: rename `remove_entry()` to `remove_entry_from_dir()` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 09/20] refs: split `ref_cache` code into separate files Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 10/20] ref-cache: introduce a new type, ref_cache Michael Haggerty
2017-04-07 11:32 ` Duy Nguyen
2017-04-16 4:52 ` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 11/20] refs: record the ref_store in ref_cache, not ref_dir Michael Haggerty
2017-04-07 11:38 ` Duy Nguyen
2017-04-16 5:49 ` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 12/20] ref-cache: use a callback function to fill the cache Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 13/20] refs: handle "refs/bisect/" in `loose_fill_ref_dir()` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 14/20] do_for_each_entry_in_dir(): eliminate `offset` argument Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 15/20] get_loose_ref_dir(): function renamed from get_loose_refs() Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 16/20] get_loose_ref_cache(): new function Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 17/20] cache_ref_iterator_begin(): make function smarter Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 18/20] commit_packed_refs(): use reference iteration Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 19/20] files_pack_refs(): " Michael Haggerty
2017-04-07 11:51 ` Duy Nguyen
2017-04-16 6:13 ` Michael Haggerty
2017-03-31 14:11 ` [PATCH v2 20/20] do_for_each_entry_in_dir(): delete function Michael Haggerty
2017-03-31 16:01 ` [PATCH v2 00/20] Separate `ref_cache` into a separate module Junio C Hamano
2017-04-01 5:16 ` Michael Haggerty
2017-04-05 14:03 ` Duy Nguyen
2017-04-07 11:53 ` Duy Nguyen
2017-04-16 6:15 ` Michael Haggerty
2017-04-01 21:26 ` Ramsay Jones
2017-04-02 3:38 ` Junio C Hamano
2017-04-02 14:48 ` Ramsay Jones
2017-04-02 16:44 ` Junio C Hamano
2017-04-01 6:20 ` Jeff King
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAGZ79kZ9uGjhN5n8YAdUh2xqDMxTmmfsa7rCEWMk-Bsp5uxncg@mail.gmail.com \
--to=sbeller@google.com \
--cc=avarab@gmail.com \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=mhagger@alum.mit.edu \
--cc=novalis@novalis.org \
--cc=pclouds@gmail.com \
--cc=peff@peff.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).