On 08/14/2012 05:13 AM, Daniel P. Berrange wrote:
From: "Daniel P. Berrange" <berrange@redhat.com>
The current virRandomBits() API is only usable if the caller wants a random number in the range [0, (n-1)] where n is a power of two. This adds a virRandom() API which generates a double in the range [0.0,1.0] with 48 bits of entropy. It then also adds a virRandomInt(uint32_t max) API which generates an unsigned in the range [0,@max]
+uint32_t virRandomInt(uint32_t max) +{ + double val = virRandom(); + return val * max;
I just realized this always goes through the slower path of using a double; it might be worth doing a quick filter for a power of 2, and forward that directly through virRandomBits(); I'll propose a followup patch. I find it easier to write virRandomInt(256) than virRandomBits(8), for example. -- Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org