1 files changed, 109 insertions, 0 deletions
diff --git a/usr.sbin/nsd/bitset.c b/usr.sbin/nsd/bitset.c
new file mode 100644
index 00000000000..f1f850e4db6
--- /dev/null
+++ b/usr.sbin/nsd/bitset.c
@@ -0,0 +1,109 @@
+/*
+ * bitset.h -- Dynamic bitset.
+ *
+ * Copyright (c) 2001-2020, NLnet Labs. All rights reserved.
+ *
+ * See LICENSE for the license.
+ *
+ */
+#include "config.h"
+#include "bitset.h"
+
+#include <assert.h>
+#include <limits.h>
+#include <string.h>
+
+size_t nsd_bitset_size(size_t bits)
+{
+	if(bits == 0)
+		bits++;
+
+	return (bits / CHAR_BIT) + ((bits % CHAR_BIT) != 0) + sizeof(size_t);
+}
+
+void nsd_bitset_zero(struct nsd_bitset *bset)
+{
+	size_t sz;
+
+	assert(bset != NULL);
+
+	sz = nsd_bitset_size(bset->size) - sizeof(bset->size);
+	assert(sz > 0);
+	memset(bset->bits, 0, sz);
+}
+
+void nsd_bitset_init(struct nsd_bitset *bset, size_t bits)
+{
+	assert(bset != NULL);
+	if (bits == 0)
+		bits++;
+
+	bset->size = bits;
+	nsd_bitset_zero(bset);
+}
+
+int nsd_bitset_isset(struct nsd_bitset *bset, size_t bit)
+{
+	assert(bset != NULL);
+	if(bit >= bset->size)
+		return 0;
+
+	return (bset->bits[ (bit / CHAR_BIT) ] & (1 << (bit % CHAR_BIT))) != 0;
+}
+
+void nsd_bitset_set(struct nsd_bitset *bset, size_t bit)
+{
+	assert(bset != NULL);
+	assert(bset->size > bit);
+	bset->bits[ (bit / CHAR_BIT) ] |= (1 << (bit % CHAR_BIT));
+}
+
+void nsd_bitset_unset(struct nsd_bitset *bset, size_t bit)
+{
+	assert(bset != NULL);
+	assert(bset->size > bit);
+	bset->bits[ (bit / CHAR_BIT) ] &= ~(1 << (bit % CHAR_BIT));
+}
+
+void nsd_bitset_or(
+	struct nsd_bitset *destset,
+	struct nsd_bitset *srcset1,
+	struct nsd_bitset *srcset2)
+{
+	size_t i, n, size, bytes;
+	unsigned char bits;
+	unsigned int mask;
+
+	assert(destset != NULL);
+	assert(srcset1 != NULL);
+	assert(srcset2 != NULL);
+
+	size = destset->size;
+	bytes = (size / CHAR_BIT) + ((size % CHAR_BIT) != 0);
+
+	for(i = 0; i < bytes; i++) {
+		bits = 0;
+
+		n = (srcset1->size / CHAR_BIT);
+		if (n > i) {
+			bits |= srcset1->bits[i];
+		} else {
+			n += ((srcset1->size % CHAR_BIT) != 0);
+			mask = (1 << ((srcset1->size % CHAR_BIT) + 1)) - 1;
+			if (n > i) {
+				bits |= (srcset1->bits[i] & mask);
+			}
+		}
+		n = (srcset2->size / CHAR_BIT);
+		if (n > i) {
+			bits |= srcset2->bits[i];
+		} else {
+			n += ((srcset2->size % CHAR_BIT) != 0);
+			mask = (1 << ((srcset2->size % CHAR_BIT) + 1)) - 1;
+			if (n > i) {
+				bits |= (srcset2->bits[i] & mask);
+			}
+		}
+		destset->bits[i] = bits;
+	}
+}