Re: [Libguestfs] [PATCH v2 3/4] common: Add isaligned helper module
On 08/03/2018 02:28 PM, 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 in
https://www.redhat.com/archives/libguestfs/2018-August/msg00036.html
---
common/include/isaligned.h | 50 ++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)
create mode 100644 common/include/isaligned.h
+/* Return true if size is a multiple of align. align must be power
of 2.
+ *
+ * Suggested by Eric Blake. See:
+ * https://www.redhat.com/archives/libguestfs/2018-August/msg00036.html
Do we need this comment in the code? I'm fine if it is just in the
commit message.
+ */
+static inline bool
+is_aligned (unsigned int size, unsigned int align)
+{
+ return !(size & (align - 1));
+}
Should we assert() that align is indeed a power of 2, to make it harder
for callers to misuse this function? Otherwise, looks okay to me.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org