[libvirt] [PATCHv3 1/4] bitmap: add virBitmapCountBits

[Viktor Mihajlovski]

On 10/25/2012 03:36 AM, Eric Blake wrote:
> Sometimes it's handy to know how many bits are set.
>
> * src/util/bitmap.h (virBitmapCountBits): New prototype.
> (virBitmapNextSetBit): Use correct type.
> * src/util/bitmap.c (virBitmapNextSetBit): Likewise.
> (virBitmapCountBits): New function.
> * src/libvirt_private.syms (bitmap.h): Export it.
> * tests/virbitmaptest.c (test2): Test it.
You might want to add a sign-off.
> +/* Return the number of bits currently set in the map.  */
> +size_t
> +virBitmapCountBits(virBitmapPtr bitmap)
> +{
> +    size_t i;
> +    size_t ret = 0;
> +    int tail = bitmap->max_bit % VIR_BITMAP_BITS_PER_UNIT;
> +
> +    /* Ensure tail bits are clear.  */
> +    if (tail)
> +        bitmap->map[bitmap->map_len - 1] &=
> +            -1UL >> (VIR_BITMAP_BITS_PER_UNIT - tail);
Probably not necessary, as the bitmap is initialized to zero.

Works for me.

-- 

Mit freundlichen Grüßen/Kind Regards
    Viktor Mihajlovski

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