# [PATCH] strbuf: avoid redundant reset in strbuf_getwholeline() 3 messages from 2026-07-14 to 2026-07-14. Participants: René Scharfe, Junio C Hamano, Jeff King. Thread: https://gitlist.dev/t/65992 ## René Scharfe, 2026-07-14 08:45 Subject: [PATCH] strbuf: avoid redundant reset in strbuf_getwholeline() Message-ID: ``` The HAVE_GETDELIM variant of strbuf_getwholeline() calls strbuf_reset() on the strbuf before handing it over to getdelim(3). This is unnecessary: - getdelim(3) doesn't care whether the old buffer contents is NUL-terminated and has no access to ->len, - on success getdelim(3) NUL-terminates the buffer and we set ->len, - on error we either call strbuf_init() or strbuf_reset(). Remove the superfluous preparatory call. Signed-off-by: René Scharfe --- strbuf.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/strbuf.c b/strbuf.c index 764b629927..44955669e8 100644 --- a/strbuf.c +++ b/strbuf.c @@ -646,8 +646,6 @@ int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term) if (feof(fp)) return EOF; - strbuf_reset(sb); - /* Translate slopbuf to NULL, as we cannot call realloc on it */ if (!sb->alloc) sb->buf = NULL; -- 2.55.0 ``` ## Junio C Hamano, 2026-07-14 16:40 Subject: Re: [PATCH] strbuf: avoid redundant reset in strbuf_getwholeline() Message-ID: In-Reply-To: ``` René Scharfe writes: > The HAVE_GETDELIM variant of strbuf_getwholeline() calls strbuf_reset() > on the strbuf before handing it over to getdelim(3). This is > unnecessary: > > - getdelim(3) doesn't care whether the old buffer contents is > NUL-terminated and has no access to ->len, > - on success getdelim(3) NUL-terminates the buffer and we set ->len, > - on error we either call strbuf_init() or strbuf_reset(). > > Remove the superfluous preparatory call. > > Signed-off-by: René Scharfe > --- > strbuf.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/strbuf.c b/strbuf.c > index 764b629927..44955669e8 100644 > --- a/strbuf.c > +++ b/strbuf.c > @@ -646,8 +646,6 @@ int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term) > if (feof(fp)) > return EOF; > > - strbuf_reset(sb); > - This is well explained and makes perfect sense. Thanks. Will apply and mark for 'next'. > /* Translate slopbuf to NULL, as we cannot call realloc on it */ > if (!sb->alloc) > sb->buf = NULL; ``` ## Jeff King, 2026-07-14 21:49 Subject: Re: [PATCH] strbuf: avoid redundant reset in strbuf_getwholeline() Message-ID: <20260714214941.GB4095533@coredump.intra.peff.net> In-Reply-To: ``` On Tue, Jul 14, 2026 at 10:45:59AM +0200, René Scharfe wrote: > The HAVE_GETDELIM variant of strbuf_getwholeline() calls strbuf_reset() > on the strbuf before handing it over to getdelim(3). This is > unnecessary: > > - getdelim(3) doesn't care whether the old buffer contents is > NUL-terminated and has no access to ->len, > - on success getdelim(3) NUL-terminates the buffer and we set ->len, > - on error we either call strbuf_init() or strbuf_reset(). > > Remove the superfluous preparatory call. Good catch. In the original version of strbuf_getwholeline() we were missing that reset on error, which is why this was included. I think it became redundant in b70904306f (strbuf_getwholeline: NUL-terminate getdelim buffer on error, 2016-03-05). -Peff ```