Re: [Qemu-block] [PATCH v6 06/22] osdep: Introduce qemu_dup

[Kevin Wolf]

Am 17.06.2016 um 14:32 hat Kevin Wolf geschrieben:
> Am 03.06.2016 um 10:49 hat Fam Zheng geschrieben:
> > This takes care of both the CLOEXEC flag and fd-path mapping for image
> > locking.
> > 
> > Signed-off-by: Fam Zheng <address@hidden>
> > ---
> >  include/qemu/osdep.h | 3 +++
> >  util/osdep.c         | 9 +++++++++
> >  2 files changed, 12 insertions(+)
> > 
> > diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
> > index 749214a..89c63c7 100644
> > --- a/include/qemu/osdep.h
> > +++ b/include/qemu/osdep.h
> > @@ -281,6 +281,9 @@ int qemu_madvise(void *addr, size_t len, int advice);
> >  int qemu_open(const char *name, int flags, ...);
> >  int qemu_close(int fd);
> >  int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive);
> > +#ifndef _WIN32
> > +int qemu_dup(int fd);
> > +#endif
> >  int qemu_unlock_fd(int fd, int64_t start, int64_t len);
> >  
> >  #if defined(__HAIKU__) && defined(__i386__)
> > diff --git a/util/osdep.c b/util/osdep.c
> > index 085ed52..1c87c1e 100644
> > --- a/util/osdep.c
> > +++ b/util/osdep.c
> > @@ -133,6 +133,15 @@ fail:
> >      return -1;
> >  }
> >  
> > +int qemu_dup(int fd)
> > +{
> > +    int r = qemu_dup_flags(fd, 0);
> 
> This clears all file status flags that might be set. I don't think we
> use any of them (on Linux at least, raw-posix still seems to use it for
> platform without O_DIRECT), but isn't this still surprising?

Maybe this means that qemu_dup_flags() should call qemu_dup() instead of
the other way round.

Kevin