Re: [Libguestfs] [libnbd PATCH 01/20] fuse: Only support defined fallocate modes

On Tue, Jun 08, 2021 at 09:53:42AM +0200, Martin Kletzander wrote: > None of them is defined on FreeBSD, for example, and the only other way to make > the code compile would be to define it ourselves. > > Signed-off-by: Martin Kletzander <mkletzan(a)redhat.com&gt; > --- > fuse/operations.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/fuse/operations.c b/fuse/operations.c > index de04ba7b6d72..098613f66f33 100644 > --- a/fuse/operations.c > +++ b/fuse/operations.c > @@ -440,6 +440,9 @@ nbdfuse_fallocate (const char *path, int mode, off_t offset, off_t len, > if (readonly) > return -EACCES; > > +#if defined(FALLOC_FL_PUNCH_HOLE) || defined(FALLOC_FL_ZERO_RANGE) > +# if defined(FALLOC_FL_PUNCH_HOLE) I like this indentation of preprocessor directives... > + > if (mode & FALLOC_FL_PUNCH_HOLE) { > if (!nbd_can_trim (nbd.ptr[0])) > return -EOPNOTSUPP; /* Trim not supported. */ > @@ -448,6 +451,9 @@ nbdfuse_fallocate (const char *path, int mode, off_t offset, off_t len, > return 0; > } > } > +#endif /*# if defined(FALLOC_FL_PUNCH_HOLE) */ > + > +#if defined(FALLOC_FL_ZERO_RANGE) ...but you forgot it here > /* As of FUSE 35 this is not supported by the kernel module and it > * always returns EOPNOTSUPP. > */ > @@ -470,7 +476,9 @@ nbdfuse_fallocate (const char *path, int mode, off_t offset, off_t len, > return 0; > } > } > +#endif /* defined(FALLOC_FL_ZERO_RANGE) */ ...as well as here. > else > +#endif /* defined(FALLOC_FL_PUNCH_HOLE) || defined(FALLOC_FL_ZERO_RANGE) */ > return -EOPNOTSUPP; > } To some extent, it would also be possible to write: #ifndef FALLOC_FL_PUNCH_HOLE # define FALLOC_FL_PUNCH_HOLE 0 #endif #ifndef FALLOC_FL_ZERO_RANGE # define FALLOC_FL_ZERO_RANGE 0 #endif static int nbdfuse_fallocate(...) { ... if (mode & FALLOC_FL_PUNCH_HOLE) { ... } else if (mode & FALLOC_FL_ZERO_RANGE) { ... } else return -EOPNOTSUPP; } for fewer in-function #ifdefs, but that is a style choice, not a correctness issue, so I won't insist.

-- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org