1 files changed, 63 insertions, 0 deletions
diff --git a/src/daemon/bitmap.c b/src/daemon/bitmap.c
new file mode 100644
index 0000000..c7a6330
--- /dev/null
+++ b/src/daemon/bitmap.c
@@ -0,0 +1,63 @@
+/* -*- mode: c; c-file-style: "openbsd" -*- */
+/*
+ * Copyright (c) 2020 Vincent Bernat <bernat@luffy.cx>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* Helpers around bitmaps */
+
+#include "lldpd.h"
+
+/*
+ * Set vlan id in the bitmap
+ */
+void
+bitmap_set(uint32_t *bmap, uint16_t vlan_id)
+{
+	if (vlan_id < MAX_VLAN) bmap[vlan_id / 32] |= (((uint32_t)1) << (vlan_id % 32));
+}
+
+/*
+ * Checks if the bitmap is empty
+ */
+int
+bitmap_isempty(uint32_t *bmap)
+{
+	int i;
+
+	for (i = 0; i < VLAN_BITMAP_LEN; i++) {
+		if (bmap[i] != 0) return 0;
+	}
+
+	return 1;
+}
+
+/*
+ * Calculate the number of bits set in the bitmap to get total
+ * number of VLANs
+ */
+unsigned int
+bitmap_numbits(uint32_t *bmap)
+{
+	unsigned int num = 0;
+
+	for (int i = 0; (i < VLAN_BITMAP_LEN); i++) {
+		uint32_t v = bmap[i];
+		v = v - ((v >> 1) & 0x55555555);
+		v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
+		num += (((v + (v >> 4)) & 0x0F0F0F0F) * 0x01010101) >> 24;
+	}
+
+	return num;
+}