From: Glen Choo <chooglen@google.com>
To: Linus Arver via GitGitGadget <gitgitgadget@gmail.com>,
git@vger.kernel.org
Cc: Linus Arver <linusa@google.com>
Subject: Re: [PATCH 1/5] trailer: separate public from internal portion of trailer_iterator
Date: Mon, 07 Aug 2023 14:16:52 -0700 [thread overview]
Message-ID: <kl6l8rama6yj.fsf@chooglen-macbookpro.roam.corp.google.com> (raw)
In-Reply-To: <0bce4d4b0d5650edf477cbbcc9f4e467b7981426.1691211879.git.gitgitgadget@gmail.com>
As someone who isn't that familiar with trailer code, and will have less
time for the ML soon, this is more of a quick drive-by..
"Linus Arver via GitGitGadget" <gitgitgadget@gmail.com> writes:
> +#define private __private_to_trailer_c__do_not_use
> +
> void trailer_iterator_init(struct trailer_iterator *iter, const char *msg)
> {
> struct process_trailer_options opts = PROCESS_TRAILER_OPTIONS_INIT;
> strbuf_init(&iter->key, 0);
> strbuf_init(&iter->val, 0);
> opts.no_divider = 1;
> - trailer_info_get(&iter->info, msg, &opts);
> - iter->cur = 0;
> + trailer_info_get(&iter->private.info, msg, &opts);
> + iter->private.cur = 0;
> }
> --- a/trailer.h
> +++ b/trailer.h
> @@ -119,8 +119,10 @@ struct trailer_iterator {
> struct strbuf val;
>...
> /* private */
> - struct trailer_info info;
> - size_t cur;
> + struct {
> + struct trailer_info info;
> + size_t cur;
> + } __private_to_trailer_c__do_not_use;
> };
Interesting approach to "private members". I like that it's fairly
lightweight and clear. On the other hand, I think this will fail to
autocomplete on most people's development setups, and I don't think this
is worth the tradeoff.
This is the first instance of this I could find in the codebase. I'm not
really opposed to having a new way of doing things, but it would be nice
for us to be consistent with how we handle private members. Other
approaches I've seen are:
- Using a "larger" struct to hold private members and "downcasting" for
public users (struct dir_iterator and struct dir_iterator_int). I
dislike this because I think this enables 'wrong' memory access too
easily.
(As an aside, if we really wanted to 'strictly' enforce privateness in
this patch, shouldn't we move the "#define private" into the .c file,
the way dir_iterator_int is in the .c file?)
- Prefixing private members with "__" (khash.h and other header-only
libraries use this at least, not sure if we have this in the 'main
tree'). I think this works pretty well most of the time.
- Just marking private members with a comment. IMO this is good enough
the vast majority of the time - if something is private for a good
reason, it's unlikely to get used accidentally anyway. But properly
enforcing "privateness" is worthy goal anyway.
Personally, I think a decent tradeoff between enforcement and ergonomics
would be to use an inner struct like you do here, but name it something
autocomplete-friendly and obviously private, like "private" or
"_private". I suspect self-regulation and code review should be enough
to catch nearly all accidental uses of private members.
next prev parent reply other threads:[~2023-08-07 21:17 UTC|newest]
Thread overview: 72+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-05 5:04 [PATCH 0/5] Trailer readability cleanups Linus Arver via GitGitGadget
2023-08-05 5:04 ` [PATCH 1/5] trailer: separate public from internal portion of trailer_iterator Linus Arver via GitGitGadget
2023-08-07 21:16 ` Glen Choo [this message]
2023-08-08 12:19 ` Phillip Wood
2023-08-10 23:15 ` Linus Arver
2023-08-10 22:50 ` Linus Arver
2023-08-05 5:04 ` [PATCH 2/5] trailer: split process_input_file into separate pieces Linus Arver via GitGitGadget
2023-08-07 22:39 ` Glen Choo
2023-08-11 0:41 ` Linus Arver
2023-08-05 5:04 ` [PATCH 3/5] trailer: split process_command_line_args into separate functions Linus Arver via GitGitGadget
2023-08-07 22:51 ` Glen Choo
2023-08-11 0:59 ` Linus Arver
2023-08-11 1:02 ` Linus Arver
2023-08-11 21:11 ` Glen Choo
2023-08-05 5:04 ` [PATCH 4/5] trailer: teach find_patch_start about --no-divider Linus Arver via GitGitGadget
2023-08-07 23:28 ` Glen Choo
2023-08-11 1:25 ` Linus Arver
2023-08-11 20:51 ` Glen Choo
2023-08-05 5:04 ` [PATCH 5/5] trailer: rename *_DEFAULT enums to *_UNSPECIFIED Linus Arver via GitGitGadget
2023-08-07 23:45 ` Glen Choo
2023-08-11 18:00 ` Linus Arver
2023-09-09 6:16 ` [PATCH v2 0/6] Trailer readability cleanups Linus Arver via GitGitGadget
2023-09-09 6:16 ` [PATCH v2 1/6] trailer: separate public from internal portion of trailer_iterator Linus Arver via GitGitGadget
2023-09-11 17:10 ` Junio C Hamano
2023-09-09 6:16 ` [PATCH v2 2/6] trailer: split process_input_file into separate pieces Linus Arver via GitGitGadget
2023-09-11 17:10 ` Junio C Hamano
2023-09-09 6:16 ` [PATCH v2 3/6] trailer: split process_command_line_args into separate functions Linus Arver via GitGitGadget
2023-09-09 6:16 ` [PATCH v2 4/6] trailer: teach find_patch_start about --no-divider Linus Arver via GitGitGadget
2023-09-11 17:25 ` Junio C Hamano
2023-09-14 2:19 ` Linus Arver
2023-09-14 3:12 ` Junio C Hamano
2023-09-14 5:31 ` Linus Arver
2023-09-09 6:16 ` [PATCH v2 5/6] trailer: rename *_DEFAULT enums to *_UNSPECIFIED Linus Arver via GitGitGadget
2023-09-11 18:54 ` Junio C Hamano
2023-09-14 2:41 ` Linus Arver
2023-09-14 3:16 ` Junio C Hamano
2023-09-22 18:23 ` Linus Arver
2023-09-22 19:48 ` Junio C Hamano
2023-09-26 5:30 ` Linus Arver
2023-09-09 6:16 ` [PATCH v2 6/6] trailer: use offsets for trailer_start/trailer_end Linus Arver via GitGitGadget
2023-09-11 19:01 ` Junio C Hamano
2023-09-14 1:21 ` Linus Arver
2023-09-14 3:18 ` Linus Arver
2023-09-22 19:50 ` [PATCH v3 0/9] Trailer readability cleanups Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 1/9] trailer: separate public from internal portion of trailer_iterator Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 2/9] trailer: split process_input_file into separate pieces Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 3/9] trailer: split process_command_line_args into separate functions Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 4/9] trailer: rename *_DEFAULT enums to *_UNSPECIFIED Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 5/9] commit: ignore_non_trailer computes number of bytes to ignore Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 6/9] trailer: find the end of the log message Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 7/9] trailer: use offsets for trailer_start/trailer_end Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 8/9] trailer: only use trailer_block_* variables if trailers were found Linus Arver via GitGitGadget
2023-09-22 19:50 ` [PATCH v3 9/9] trailer: make stack variable names match field names Linus Arver via GitGitGadget
2023-09-22 22:47 ` [PATCH v3 0/9] Trailer readability cleanups Junio C Hamano
2023-09-22 23:13 ` Linus Arver
2023-09-23 0:48 ` Junio C Hamano
2023-09-26 5:40 ` Linus Arver
2023-09-26 6:22 ` [PATCH v4 0/4] " Linus Arver via GitGitGadget
2023-09-26 6:22 ` [PATCH v4 1/4] commit: ignore_non_trailer computes number of bytes to ignore Linus Arver via GitGitGadget
2023-09-26 6:22 ` [PATCH v4 2/4] trailer: find the end of the log message Linus Arver via GitGitGadget
2023-09-28 23:16 ` Jonathan Tan
2023-10-20 0:24 ` Linus Arver
2023-10-20 0:36 ` Junio C Hamano
2023-09-26 6:22 ` [PATCH v4 3/4] trailer: use offsets for trailer_start/trailer_end Linus Arver via GitGitGadget
2023-09-26 6:22 ` [PATCH v4 4/4] trailer: only use trailer_block_* variables if trailers were found Linus Arver via GitGitGadget
2023-10-20 19:01 ` [PATCH v5 0/3] Trailer readability cleanups Linus Arver via GitGitGadget
2023-10-20 19:01 ` [PATCH v5 1/3] commit: ignore_non_trailer computes number of bytes to ignore Linus Arver via GitGitGadget
2023-10-20 19:01 ` [PATCH v5 2/3] trailer: find the end of the log message Linus Arver via GitGitGadget
2023-10-20 21:29 ` Junio C Hamano
2023-12-29 6:42 ` Linus Arver
2023-12-29 21:03 ` Linus Arver
2023-10-20 19:01 ` [PATCH v5 3/3] trailer: use offsets for trailer_start/trailer_end Linus Arver via GitGitGadget
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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=kl6l8rama6yj.fsf@chooglen-macbookpro.roam.corp.google.com \
--to=chooglen@google.com \
--cc=git@vger.kernel.org \
--cc=gitgitgadget@gmail.com \
--cc=linusa@google.com \
/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.
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).