[libvirt] [PATCH V2 1/3] Add function to find and set next available bit
Add function to find the next available bit in the bitmap and set it.
Signed-off-by: Stefan Berger <stefanb(a)linux.vnet.ibm.com>
---
src/libvirt_private.syms | 1 +
src/util/virbitmap.c | 34 ++++++++++++++++++++++++++++++++++
src/util/virbitmap.h | 3 +++
3 files changed, 38 insertions(+)
Index: libvirt/src/util/virbitmap.c
===================================================================
--- libvirt.orig/src/util/virbitmap.c
+++ libvirt/src/util/virbitmap.c
@@ -642,3 +642,37 @@ virBitmapCountBits(virBitmapPtr bitmap)
return ret;
}
+
+
+/**
+ * virBitmapSetNextBit:
+ * @bitmap: the bitmap
+ * @pos: the position after which to search for a clear bit and set it
+ *
+ * search the first clear bit after position @pos in bitmap @bitmap
+ * and set it. @pos can be -1 to search for the first set bit.
+ * Position starts at 0.
+ *
+ * returns the position of the set bit, or -1 if no bit could be set
+ */
+size_t
+virBitmapSetNextBit(virBitmapPtr bitmap, ssize_t pos)
+{
+ if (pos < 0)
+ pos = -1;
+
+ pos++;
+
+ if (pos >= bitmap->max_bit)
+ return -1;
+
+ while (pos < bitmap->max_bit) {
+ if (!virBitmapIsSet(bitmap, pos)) {
+ ignore_value(virBitmapSetBit(bitmap, pos));
+ return pos;
+ }
+ pos++;
+ }
+
+ return -1;
+}
Index: libvirt/src/util/virbitmap.h
===================================================================
--- libvirt.orig/src/util/virbitmap.h
+++ libvirt/src/util/virbitmap.h
@@ -106,4 +106,7 @@ ssize_t virBitmapNextSetBit(virBitmapPtr
size_t virBitmapCountBits(virBitmapPtr bitmap)
ATTRIBUTE_NONNULL(1);
+size_t virBitmapSetNextBit(virBitmapPtr bitmap, ssize_t pos)
+ ATTRIBUTE_NONNULL(1);
+
#endif
Index: libvirt/src/libvirt_private.syms
===================================================================
--- libvirt.orig/src/libvirt_private.syms
+++ libvirt/src/libvirt_private.syms
@@ -22,6 +22,7 @@ virBitmapNextSetBit;
virBitmapParse;
virBitmapSetAll;
virBitmapSetBit;
+virBitmapSetNextBit;
virBitmapSize;
virBitmapString;
virBitmapToData;