1 files changed, 99 insertions, 0 deletions
diff --git a/bitmap.c b/bitmap.c
new file mode 100644
index 0000000..b3b204b
--- /dev/null
+++ b/bitmap.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/* PASST - Plug A Simple Socket Transport
+ *  for qemu/UNIX domain socket mode
+ *
+ * PASTA - Pack A Subtle Tap Abstraction
+ *  for network namespace/tap device mode
+ *
+ * bitmap.c - bitmap handling
+ *
+ * Copyright Red Hat
+ * Author: Stefano Brivio <sbrivio@redhat.com>
+ */
+
+#include "bitmap.h"
+
+/**
+ * bitmap_set() - Set single bit in bitmap
+ * @map:	Pointer to bitmap
+ * @bit:	Bit number to set
+ */
+void bitmap_set(uint8_t *map, unsigned bit)
+{
+	unsigned long *word = (unsigned long *)map + BITMAP_WORD(bit);
+
+	*word |= BITMAP_BIT(bit);
+}
+
+/**
+ * bitmap_clear() - Clear single bit in bitmap
+ * @map:	Pointer to bitmap
+ * @bit:	Bit number to clear
+ */
+/* cppcheck-suppress unusedFunction */
+void bitmap_clear(uint8_t *map, unsigned bit)
+{
+	unsigned long *word = (unsigned long *)map + BITMAP_WORD(bit);
+
+	*word &= ~BITMAP_BIT(bit);
+}
+
+/**
+ * bitmap_isset() - Check for set bit in bitmap
+ * @map:	Pointer to bitmap
+ * @bit:	Bit number to check
+ *
+ * Return: true if given bit is set, false if it's not
+ */
+bool bitmap_isset(const uint8_t *map, unsigned bit)
+{
+	const unsigned long *word
+		= (const unsigned long *)map + BITMAP_WORD(bit);
+
+	return !!(*word & BITMAP_BIT(bit));
+}
+
+/**
+ * bitmap_or() - Logical disjunction (OR) of two bitmaps
+ * @dst:	Pointer to result bitmap
+ * @size:	Size of bitmaps, in bytes
+ * @a:		First operand
+ * @b:		Second operand
+ */
+/* cppcheck-suppress unusedFunction */
+void bitmap_or(uint8_t *dst, size_t size, const uint8_t *a, const uint8_t *b)
+{
+	unsigned long *dw = (unsigned long *)dst;
+	unsigned long *aw = (unsigned long *)a;
+	unsigned long *bw = (unsigned long *)b;
+	size_t i;
+
+	for (i = 0; i < size / sizeof(long); i++, dw++, aw++, bw++)
+		*dw = *aw | *bw;
+
+	for (i = size / sizeof(long) * sizeof(long); i < size; i++)
+		dst[i] = a[i] | b[i];
+}
+
+/**
+ * bitmap_and_not() - Logical conjunction with complement (AND NOT) of bitmap
+ * @dst:	Pointer to result bitmap
+ * @size:	Size of bitmaps, in bytes
+ * @a:		First operand
+ * @b:		Second operand
+ */
+void bitmap_and_not(uint8_t *dst, size_t size,
+		   const uint8_t *a, const uint8_t *b)
+{
+	unsigned long *dw = (unsigned long *)dst;
+	unsigned long *aw = (unsigned long *)a;
+	unsigned long *bw = (unsigned long *)b;
+	size_t i;
+
+	for (i = 0; i < size / sizeof(long); i++, dw++, aw++, bw++)
+		*dw = *aw & ~*bw;
+
+	for (i = size / sizeof(long) * sizeof(long); i < size; i++)
+		dst[i] = a[i] & ~b[i];
+}