On 04/02/2013 01:42 AM, Osier Yang wrote:
--- src/libvirt_private.syms | 1 + src/util/virbitmap.c | 30 ++++++++++++++++++++++++++++++ src/util/virbitmap.h | 3 +++ 3 files changed, 34 insertions(+)
Since there already is a "virBitmapIsAllSet()" - why isn't it used? I see callers which do "if (virBitmapIsAllSet(...)" and "if (!virBitmapIsAllSet(...)". If you're going to have a AllClear(), then why not change those ! callers to use AllClear()... I only wonder about the last comparison - it's the "-1" logic that throws me off especially since the IsAllSet() code is doing a comparison. It also stands to reason that tests/virbitmaptest.c could add new tests to ensure you did get the logic right. John
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 96eea0a..35ac957 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -1048,6 +1048,7 @@ virBitmapEqual; virBitmapFormat; virBitmapFree; virBitmapGetBit; +virBitmapIsAllClear; virBitmapIsAllSet; virBitmapNew; virBitmapNewCopy; diff --git a/src/util/virbitmap.c b/src/util/virbitmap.c index 21509ac..99a8572 100644 --- a/src/util/virbitmap.c +++ b/src/util/virbitmap.c @@ -591,6 +591,36 @@ bool virBitmapIsAllSet(virBitmapPtr bitmap) }
/** + * virBitmapIsAllClear: + * @bitmap: the bitmap to check + * + * check if all bits in @bitmap are clear + */ +bool virBitmapIsAllClear(virBitmapPtr bitmap) +{ + int i; + int unusedBits; + size_t sz; + + unusedBits = bitmap->map_len * VIR_BITMAP_BITS_PER_UNIT - bitmap->max_bit; + + sz = bitmap->map_len; + if (unusedBits > 0) + sz--; + + for (i = 0; i < sz; i++) + if (bitmap->map[i] != 0) + return false; + + if (unusedBits > 0) { + if ((bitmap->map[sz] & ((1UL << (VIR_BITMAP_BITS_PER_UNIT - unusedBits)) - 1))) + return false; + } + + return true; +} + +/** * virBitmapNextSetBit: * @bitmap: the bitmap * @pos: the position after which to search for a set bit diff --git a/src/util/virbitmap.h b/src/util/virbitmap.h index 044c7a6..b682523 100644 --- a/src/util/virbitmap.h +++ b/src/util/virbitmap.h @@ -100,6 +100,9 @@ void virBitmapClearAll(virBitmapPtr bitmap) bool virBitmapIsAllSet(virBitmapPtr bitmap) ATTRIBUTE_NONNULL(1);
+bool virBitmapIsAllClear(virBitmapPtr bitmap) + ATTRIBUTE_NONNULL(1); + ssize_t virBitmapNextSetBit(virBitmapPtr bitmap, ssize_t pos) ATTRIBUTE_NONNULL(1);