From: Junio C Hamano <gitster@pobox.com>
To: "Martin Ågren" <martin.agren@gmail.com>
Cc: git@vger.kernel.org, "Đoàn Trần Công Danh" <congdanhqx@gmail.com>
Subject: Re: [PATCH 3/4] strbuf: introduce `strbuf_attachstr()`
Date: Mon, 20 Apr 2020 12:39:16 -0700 [thread overview]
Message-ID: <xmqqzhb6q74r.fsf@gitster.c.googlers.com> (raw)
In-Reply-To: <c3012f1da361af354a904f821b83d61f2534ccb2.1587297254.git.martin.agren@gmail.com> ("Martin =?utf-8?Q?=C3=85gren=22's?= message of "Sun, 19 Apr 2020 14:32:29 +0200")
Martin Ågren <martin.agren@gmail.com> writes:
> +/**
> + * Attach a string to a buffer similar to `strbuf_attachstr_len()`.
> + * Useful if you do not know the length of the string.
> + */
> +static inline void strbuf_attachstr(struct strbuf *sb, char *str)
> +{
> + size_t len = strlen(str);
> +
> + strbuf_attach(sb, str, len, len + 1);
> +}
This is somewhat worrysome in that the interface is _so_ simple that
people may fail to see that str must be allocated piece of memory,
and it is preferrable if string fully fills the allocation.
We should repeat that (instead of just trusting "similar to ..."
would tell them enough) in the doc, perhaps?
> diff --git a/trailer.c b/trailer.c
> index 0c414f2fed..56c4027943 100644
> --- a/trailer.c
> +++ b/trailer.c
> @@ -1095,7 +1095,7 @@ void trailer_info_get(struct trailer_info *info, const char *str,
> for (ptr = trailer_lines; *ptr; ptr++) {
> if (last && isspace((*ptr)->buf[0])) {
> struct strbuf sb = STRBUF_INIT;
> - strbuf_attach(&sb, *last, strlen(*last), strlen(*last));
> + strbuf_attachstr(&sb, *last);
> strbuf_addbuf(&sb, *ptr);
> *last = strbuf_detach(&sb, NULL);
> continue;
This is not wrong per-se, but it is unclear if use of strbuf_attach*
family to avoid an explicit malloc/copy/free is buying much at this
callsite. Simplifying the code here of course is not within the
scope of this series.
next prev parent reply other threads:[~2020-04-20 19:39 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-18 3:54 [PATCH] mailinfo.c::convert_to_utf8: reuse strlen info Đoàn Trần Công Danh
2020-04-18 19:56 ` Martin Ågren
2020-04-18 20:18 ` [PATCH 0/6] strbuf: simplify `strbuf_attach()` usage Martin Ågren
2020-04-18 20:18 ` [PATCH 1/6] am: use `strbuf_attach()` correctly Martin Ågren
2020-04-18 20:18 ` [PATCH 2/6] strbuf_attach: correctly pass in `strlen() + 1` for `alloc` Martin Ågren
2020-04-18 20:18 ` [PATCH 3/6] strbuf: use `strbuf_attach()` correctly Martin Ågren
2020-04-18 20:18 ` [PATCH 4/6] fast-import: avoid awkward use of `strbuf_attach()` Martin Ågren
2020-04-18 20:18 ` [PATCH 5/6] rerere: " Martin Ågren
2020-04-18 20:18 ` [PATCH 6/6] strbuf: simplify `strbuf_attach()` usage Martin Ågren
2020-04-19 4:44 ` [PATCH 0/6] " Martin Ågren
2020-04-19 12:32 ` [PATCH 0/4] strbuf: fix doc for `strbuf_attach()` and avoid it Martin Ågren
2020-04-19 12:32 ` [PATCH 1/4] strbuf: fix doc for `strbuf_attach()` Martin Ågren
2020-04-20 17:30 ` Junio C Hamano
2020-04-21 18:44 ` Martin Ågren
2020-04-19 12:32 ` [PATCH 2/4] strbuf: introduce `strbuf_attachstr_len()` Martin Ågren
2020-04-19 12:32 ` [PATCH 3/4] strbuf: introduce `strbuf_attachstr()` Martin Ågren
2020-04-20 19:39 ` Junio C Hamano [this message]
2020-04-21 18:47 ` Martin Ågren
2020-04-19 12:32 ` [PATCH 4/4] strbuf_attach: prefer `strbuf_attachstr_len()` Martin Ågren
2020-04-18 23:12 ` [PATCH] mailinfo.c::convert_to_utf8: reuse strlen info Junio C Hamano
2020-04-19 2:48 ` Danh Doan
2020-04-19 4:34 ` Martin Ågren
2020-04-19 5:32 ` Junio C Hamano
2020-04-19 11:00 ` [PATCH v2 0/3] mailinfo: disallow and complains about NUL character Đoàn Trần Công Danh
2020-04-19 11:00 ` [PATCH v2 1/3] t4254: merge 2 steps of a single test Đoàn Trần Công Danh
2020-04-19 12:25 ` Martin Ågren
2020-04-19 14:17 ` Danh Doan
2020-04-19 11:00 ` [PATCH v2 2/3] mailinfo.c::convert_to_utf8: reuse strlen info Đoàn Trần Công Danh
2020-04-19 12:29 ` Martin Ågren
2020-04-19 14:16 ` Danh Doan
2020-04-20 19:59 ` Junio C Hamano
2020-04-20 23:53 ` Danh Doan
2020-04-19 11:00 ` [PATCH v2 3/3] mailinfo: disallow NUL character in mail's header Đoàn Trần Công Danh
2020-04-19 12:30 ` Martin Ågren
2020-04-19 14:24 ` Danh Doan
2020-04-20 23:54 ` [PATCH v3 0/3] Disallow NUL character in mailinfo Đoàn Trần Công Danh
2020-04-20 23:54 ` [PATCH v3 1/3] t4254: merge 2 steps of a single test Đoàn Trần Công Danh
2020-04-20 23:54 ` [PATCH v3 2/3] mailinfo.c: avoid strlen on strings that can contains NUL Đoàn Trần Công Danh
2020-04-20 23:54 ` [PATCH v3 3/3] mailinfo: disallow NUL character in mail's header Đoàn Trần Công Danh
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=xmqqzhb6q74r.fsf@gitster.c.googlers.com \
--to=gitster@pobox.com \
--cc=congdanhqx@gmail.com \
--cc=git@vger.kernel.org \
--cc=martin.agren@gmail.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.