From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
To: Junio C Hamano <gitster@pobox.com>
Cc: Eric Wong <e@80x24.org>,
larsxschneider@gmail.com, git@vger.kernel.org, jnareb@gmail.com
Subject: Re: [PATCH v2 2/2] read-cache: make sure file handles are not inherited by child processes
Date: Tue, 25 Oct 2016 12:33:54 +0200 (CEST) [thread overview]
Message-ID: <alpine.DEB.2.20.1610251230150.3264@virtualbox> (raw)
In-Reply-To: <xmqqwpgx4j89.fsf@gitster.mtv.corp.google.com>
Hi Junio,
On Mon, 24 Oct 2016, Junio C Hamano wrote:
> Eric Wong <e@80x24.org> writes:
>
> > larsxschneider@gmail.com wrote:
> >> +++ b/read-cache.c
> >> @@ -156,7 +156,11 @@ void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
> >> static int ce_compare_data(const struct cache_entry *ce, struct stat *st)
> >> {
> >> int match = -1;
> >> - int fd = open(ce->name, O_RDONLY);
> >> + int fd = open(ce->name, O_RDONLY | O_CLOEXEC);
> >> +
> >> + if (O_CLOEXEC && fd < 0 && errno == EINVAL)
> >> + /* Try again w/o O_CLOEXEC: the kernel might not support it */
> >> + fd = open(ce->name, O_RDONLY);
> >
> > In the case of O_CLOEXEC != 0 and repeated EINVALs,
> > it'd be good to use something like sha1_file_open_flag as in 1/2
> > so we don't repeatedly hit EINVAL. Thanks.
>
> Sounds sane.
>
> It's just only once, so perhaps we do not mind a recursion like
> this?
>
> read-cache.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/read-cache.c b/read-cache.c
> index b594865d89..a6978b9321 100644
> --- a/read-cache.c
> +++ b/read-cache.c
> @@ -156,11 +156,14 @@ void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
> static int ce_compare_data(const struct cache_entry *ce, struct stat *st)
> {
> int match = -1;
> - int fd = open(ce->name, O_RDONLY | O_CLOEXEC);
> + static int cloexec = O_CLOEXEC;
> + int fd = open(ce->name, O_RDONLY | cloexec);
>
> - if (O_CLOEXEC && fd < 0 && errno == EINVAL)
> + if ((cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
> /* Try again w/o O_CLOEXEC: the kernel might not support it */
> - fd = open(ce->name, O_RDONLY);
> + cloexec &= ~O_CLOEXEC;
> + return ce_compare_data(ce, st);
> + }
>
That still looks overly complicated, repeatedly ORing cloexec and
recursing without need. How about this instead?
static int oflags = O_RDONLY | O_CLOEXEC;
int fd = open(ce->name, oflags);
if ((O_CLOEXEC & oflags) && fd < 0 && errno == EINVAL) {
/* Try again w/o O_CLOEXEC: the kernel might not support it */
oflags &= ~O_CLOEXEC;
fd = open(ce->name, oflags);
}
Ciao,
Dscho
next prev parent reply other threads:[~2016-10-25 10:34 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-10-24 18:02 [PATCH v2 0/2] Use CLOEXEC to avoid fd leaks larsxschneider
2016-10-24 18:02 ` [PATCH v2 1/2] sha1_file: open window into packfiles with CLOEXEC larsxschneider
2016-10-25 10:27 ` Johannes Schindelin
2016-10-25 16:58 ` Junio C Hamano
2016-10-24 18:03 ` [PATCH v2 2/2] read-cache: make sure file handles are not inherited by child processes larsxschneider
2016-10-24 18:39 ` Eric Wong
2016-10-24 19:53 ` Junio C Hamano
2016-10-25 10:33 ` Johannes Schindelin [this message]
2016-10-25 17:02 ` Junio C Hamano
2016-10-24 19:22 ` Johannes Sixt
2016-10-24 19:53 ` Lars Schneider
2016-10-25 21:39 ` Johannes Sixt
2016-10-24 18:23 ` [PATCH v2 0/2] Use CLOEXEC to avoid fd leaks Junio C Hamano
2016-10-25 11:27 ` Johannes Schindelin
2016-10-25 18:16 ` [PATCH v3 0/3] quick reroll of Lars's git_open() w/ O_CLOEXEC Junio C Hamano
2016-10-25 18:16 ` [PATCH v3 1/3] sha1_file: rename git_open_noatime() to git_open() Junio C Hamano
2016-10-25 18:16 ` [PATCH v3 2/3] sha1_file: open window into packfiles with O_CLOEXEC Junio C Hamano
2016-10-26 4:25 ` Jeff King
2016-10-26 16:23 ` Junio C Hamano
2016-10-26 16:47 ` Jeff King
2016-10-26 17:52 ` Junio C Hamano
2016-10-26 20:17 ` Jeff King
2016-10-26 21:15 ` Junio C Hamano
2016-10-27 10:24 ` Jeff King
2016-10-27 21:49 ` Junio C Hamano
2016-10-27 22:38 ` Linus Torvalds
2016-10-27 22:56 ` Junio C Hamano
2016-10-27 23:09 ` Linus Torvalds
2016-10-27 23:19 ` Linus Torvalds
2016-10-27 23:36 ` Junio C Hamano
2016-10-27 23:44 ` Linus Torvalds
2016-10-28 1:08 ` Junio C Hamano
2016-10-28 2:37 ` Junio C Hamano
2016-10-28 5:51 ` Eric Wong
2016-10-28 11:11 ` Johannes Schindelin
2016-10-28 16:13 ` Linus Torvalds
2016-10-28 16:48 ` Junio C Hamano
2016-10-28 17:38 ` Linus Torvalds
2016-10-28 17:47 ` Junio C Hamano
2016-10-29 1:26 ` Junio C Hamano
2016-10-29 8:25 ` Johannes Schindelin
2016-10-29 17:06 ` Linus Torvalds
2016-10-31 17:37 ` Junio C Hamano
2016-10-31 13:56 ` Jeff King
2016-10-31 17:55 ` Junio C Hamano
2016-10-31 18:05 ` Jeff King
2016-10-28 13:32 ` Junio C Hamano
2016-10-28 13:33 ` Junio C Hamano
2016-10-28 7:51 ` Jeff King
2016-10-25 18:16 ` [PATCH v3 3/3] read-cache: make sure file handles are not inherited by child processes Junio C Hamano
2016-10-25 21:33 ` Eric Wong
2016-10-25 22:54 ` Junio C Hamano
2016-10-25 21:48 ` [PATCH v3 0/3] quick reroll of Lars's git_open() w/ O_CLOEXEC Lars Schneider
2016-10-25 22:56 ` Junio C Hamano
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