Re: [Libguestfs] [PATCH v3 3/4] common: Add isaligned helper module

On Sun, Aug 19, 2018 at 01:13:07AM +0300, Nir Soffer wrote: > is_aligned (size, align) returns true if size is aligned to align, > assuming that align is power of 2. > > Suggested by Eric Blake in > https://www.redhat.com/archives/libguestfs/2018-August/msg00036.html > --- > common/include/isaligned.h | 51 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 51 insertions(+) > create mode 100644 common/include/isaligned.h > > diff --git a/common/include/isaligned.h b/common/include/isaligned.h You have to add this file to common/include/Makefile.am otherwise it will never be distributed.

Rich. > new file mode 100644 > index 0000000..e693820 > --- /dev/null > +++ b/common/include/isaligned.h > @@ -0,0 +1,51 @@ > +/* nbdkit > + * Copyright (C) 2018 Red Hat Inc. > + * All rights reserved. > + * > + * Redistribution and use in source and binary forms, with or without > + * modification, are permitted provided that the following conditions are > + * met: > + * > + * * Redistributions of source code must retain the above copyright > + * notice, this list of conditions and the following disclaimer. > + * > + * * Redistributions in binary form must reproduce the above copyright > + * notice, this list of conditions and the following disclaimer in the > + * documentation and/or other materials provided with the distribution. > + * > + * * Neither the name of Red Hat nor the names of its contributors may be > + * used to endorse or promote products derived from this software without > + * specific prior written permission. > + * > + * THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND > + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, > + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A > + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR > + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, > + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT > + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF > + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND > + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, > + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT > + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF > + * SUCH DAMAGE. > + */ > + > +#ifndef NBDKIT_ISALIGNED_H > +#define NBDKIT_ISALIGNED_H > + > +#include <assert.h> > +#include <stdbool.h> > + > +#include "ispowerof2.h" > + > +/* Return true if size is a multiple of align. align must be power of 2. > + */ > +static inline bool > +is_aligned (unsigned int size, unsigned int align) > +{ > + assert (is_power_of_2 (align)); > + return !(size & (align - 1)); > +} > + > +#endif /* NBDKIT_ISALIGNED_H */ > -- > 2.17.1 -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org