From: "Daniel P. Berrangé" <berrange@redhat.com>
To: Markus Armbruster <armbru@redhat.com>
Cc: "Kevin Wolf" <kwolf@redhat.com>,
"Philippe Mathieu-Daudé" <f4bug@amsat.org>,
qemu-devel@nongnu.org, qemu-block@nongnu.org,
"Max Reitz" <mreitz@redhat.com>
Subject: Re: [PATCH v4 2/6] util: refactor qemu_open_old to split off variadic args handling
Date: Tue, 25 Aug 2020 16:03:49 +0100 [thread overview]
Message-ID: <20200825150349.GV107278@redhat.com> (raw)
In-Reply-To: <874koqdb9z.fsf@dusky.pond.sub.org>
On Tue, Aug 25, 2020 at 04:56:40PM +0200, Markus Armbruster wrote:
> Daniel P. Berrangé <berrange@redhat.com> writes:
>
> > This simple refactoring prepares for future patches. The variadic args
> > handling is split from the main bulk of the open logic. The duplicated
> > calls to open() are removed in favour of updating the "flags" variable
> > to have O_CLOEXEC.
> >
> > Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
> > ---
> > util/osdep.c | 40 +++++++++++++++++++++++++++-------------
> > 1 file changed, 27 insertions(+), 13 deletions(-)
> >
> > diff --git a/util/osdep.c b/util/osdep.c
> > index 9df1b6adec..9ff92551e7 100644
> > --- a/util/osdep.c
> > +++ b/util/osdep.c
> > @@ -22,6 +22,7 @@
> > * THE SOFTWARE.
> > */
> > #include "qemu/osdep.h"
> > +#include "qapi/error.h"
> >
> > /* Needed early for CONFIG_BSD etc. */
> >
> > @@ -282,10 +283,10 @@ int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive)
> > /*
> > * Opens a file with FD_CLOEXEC set
> > */
> > -int qemu_open_old(const char *name, int flags, ...)
> > +static int
> > +qemu_open_internal(const char *name, int flags, mode_t mode)
> > {
> > int ret;
> > - int mode = 0;
> >
> > #ifndef _WIN32
> > const char *fdset_id_str;
> > @@ -323,22 +324,35 @@ int qemu_open_old(const char *name, int flags, ...)
> > }
> > #endif
> >
> > - if (flags & O_CREAT) {
> > - va_list ap;
> > -
> > - va_start(ap, flags);
> > - mode = va_arg(ap, int);
> > - va_end(ap);
> > - }
> > -
> > #ifdef O_CLOEXEC
> > - ret = open(name, flags | O_CLOEXEC, mode);
> > -#else
> > + flags |= O_CLOEXEC;
> > +#endif /* O_CLOEXEC */
> > +
> > ret = open(name, flags, mode);
> > +
> > +#ifndef O_CLOEXEC
> > if (ret >= 0) {
> > qemu_set_cloexec(ret);
> > }
> > -#endif
> > +#endif /* ! O_CLOEXEC */
>
> I dislike this part, to be honest. I find
>
> #ifdef O_CLOEXEC
> flags |= O_CLOEXEC;
> #endif /* O_CLOEXEC */
>
> ret = open(name, flags, mode);
>
> #ifndef O_CLOEXEC
> if (ret >= 0) {
> qemu_set_cloexec(ret);
> }
> #endif /* ! O_CLOEXEC */
>
> harder to read than
>
> #ifdef O_CLOEXEC
> ret = open(name, flags | O_CLOEXEC, mode);
> #else
> ret = open(name, flags, mode);
> if (ret >= 0) {
> qemu_set_cloexec(ret);
> }
> #endif
We're re-using 'flags' variable again in a later patch and want to
have O_CLOEXEC present in it then too.
Regards,
Daniel
--
|: https://berrange.com -o- https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org -o- https://fstop138.berrange.com :|
|: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
next prev parent reply other threads:[~2020-08-25 15:04 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-21 17:20 [PATCH v4 0/6] block: improve error reporting for unsupported O_DIRECT Daniel P. Berrangé
2020-08-21 17:21 ` [PATCH v4 1/6] util: rename qemu_open() to qemu_open_old() Daniel P. Berrangé
2020-08-21 17:21 ` [PATCH v4 2/6] util: refactor qemu_open_old to split off variadic args handling Daniel P. Berrangé
2020-08-25 14:56 ` Markus Armbruster
2020-08-25 15:03 ` Daniel P. Berrangé [this message]
2020-08-26 11:19 ` Markus Armbruster
2020-08-21 17:21 ` [PATCH v4 3/6] util: add Error object for qemu_open_internal error reporting Daniel P. Berrangé
2020-08-25 15:14 ` Markus Armbruster
2020-08-25 15:36 ` Daniel P. Berrangé
2020-08-26 11:03 ` Markus Armbruster
2020-08-27 13:27 ` Daniel P. Berrangé
2020-08-21 17:21 ` [PATCH v4 4/6] util: introduce qemu_open and qemu_create with " Daniel P. Berrangé
2020-08-25 15:16 ` Markus Armbruster
2020-08-21 17:21 ` [PATCH v4 5/6] util: give a specific error message when O_DIRECT doesn't work Daniel P. Berrangé
2020-08-25 15:19 ` Markus Armbruster
2020-08-25 15:23 ` Daniel P. Berrangé
2020-08-26 11:19 ` Markus Armbruster
2020-09-02 17:10 ` Daniel P. Berrangé
2020-08-21 17:21 ` [PATCH v4 6/6] block/fileb: switch to use qemu_open/qemu_create for improved errors Daniel P. Berrangé
2020-08-25 15:28 ` Markus Armbruster
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=20200825150349.GV107278@redhat.com \
--to=berrange@redhat.com \
--cc=armbru@redhat.com \
--cc=f4bug@amsat.org \
--cc=kwolf@redhat.com \
--cc=mreitz@redhat.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
/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 NNTP newsgroup(s).