From: Junio C Hamano <gitster@pobox•com>
To: Jonas 'Sortie' Termansen <sortie@maxsi•org>
Cc: git@vger•kernel.org
Subject: Re: [PATCH 9/9] Use timer_settime for new platforms
Date: Thu, 28 Aug 2014 12:43:03 -0700 [thread overview]
Message-ID: <xmqq61hc9z94.fsf@gitster.dls.corp.google.com> (raw)
In-Reply-To: <1409187862-21257-10-git-send-email-sortie@maxsi.org> (Jonas Termansen's message of "Thu, 28 Aug 2014 03:04:22 +0200")
Jonas 'Sortie' Termansen <sortie@maxsi•org> writes:
> setitimer() is an obsolescent XSI interface and may be removed in a
> future standard. Applications should use the core POSIX timer_settime()
> instead.
>
> This patch cleans up the progress reporting and changes it to try using
> timer_settime, or if that fails, setitimer. If either function is not
> provided by the system, then git-compat-util.h provides replacements
> that always fail with ENOSYS.
>
> It's important that code doesn't simply check if timer_settime is
> available as it can give false positives. Some systems like contemporary
> OpenBSD provides the function, but it unconditionally fails with ENOSYS
> at runtime.
>
> This approach allows the code using timer_settime() and setitimer() to
> be simple and readable. My first attempt used #ifdef around each use of
> timer_settime(), this quickly turned a into unmaintainable maze of
> preprocessor conditionals.
>
> Signed-off-by: Jonas 'Sortie' Termansen <sortie@maxsi•org>
> ---
> builtin/log.c | 47 ++++++++++++++++++++++++++++++++++++++++-------
> progress.c | 34 +++++++++++++++++++++++++++-------
> 2 files changed, 67 insertions(+), 14 deletions(-)
Yuck. I didn't look at the change very carefully, but are the two
interface so vastly different that you cannot emulate one in terms
of the other, and use a single API at the callsites, isolating the
knowledge of which kind of API is used to interact with the system
timer in one place (perhaps in compat/itimer.c)?
Having to sprinkle "if (is_using_timer_settime)" around means we
need to support two APIs at each and every callsite that wants timer
interrupt actions.
next prev parent reply other threads:[~2014-08-28 19:43 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-28 1:04 [PATCH 0/9] Use timer_settime for new platforms Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 1/9] git-compat-util.h: Add missing semicolon after struct itimerval Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 2/9] autoconf: Check for timer_t Jonas 'Sortie' Termansen
2014-08-28 12:03 ` Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 3/9] autoconf: Check for struct timespec Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 4/9] autoconf: Check for struct sigevent Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 5/9] autoconf: Check for struct itimerval Jonas 'Sortie' Termansen
2014-08-28 19:38 ` Junio C Hamano
2014-08-28 1:04 ` [PATCH 6/9] autoconf: Check for struct itimerspec Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 7/9] autoconf: Check for setitimer Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 8/9] autoconf: Check for timer_settime Jonas 'Sortie' Termansen
2014-08-29 15:23 ` Keller, Jacob E
2014-08-29 16:02 ` Jonas 'Sortie' Termansen
2014-08-28 1:04 ` [PATCH 9/9] Use timer_settime for new platforms Jonas 'Sortie' Termansen
2014-08-28 19:43 ` Junio C Hamano [this message]
2014-08-29 16:11 ` Keller, Jacob E
-- strict thread matches above, loose matches on Subject: below --
2014-08-29 16:42 [PATCH 1/9] git-compat-util.h: Add missing semicolon after struct itimerval Jacob Keller
2014-08-29 16:42 ` [PATCH 9/9] Use timer_settime for new platforms Jacob Keller
2014-08-29 18:02 ` Junio C Hamano
2014-08-29 18:09 ` Keller, Jacob E
2014-08-29 18:12 ` Junio C Hamano
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