Merged the hostap_2.6 updates, and the Leap of Faith work, from the hostap_update...

[mech_eap.git] / libeap / src / utils / bitfield.c

diff --git a/libeap/src/utils/bitfield.c b/libeap/src/utils/bitfield.c
new file mode 100644 (file)
index 0000000..8dcec39
--- /dev/null
+++ b/libeap/src/utils/bitfield.c
@@ -0,0 +1,89 @@
+/*
+ * Bitfield
+ * Copyright (c) 2013, Jouni Malinen <j@w1.fi>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "bitfield.h"
+
+
+struct bitfield {
+       u8 *bits;
+       size_t max_bits;
+};
+
+
+struct bitfield * bitfield_alloc(size_t max_bits)
+{
+       struct bitfield *bf;
+
+       bf = os_zalloc(sizeof(*bf) + (max_bits + 7) / 8);
+       if (bf == NULL)
+               return NULL;
+       bf->bits = (u8 *) (bf + 1);
+       bf->max_bits = max_bits;
+       return bf;
+}
+
+
+void bitfield_free(struct bitfield *bf)
+{
+       os_free(bf);
+}
+
+
+void bitfield_set(struct bitfield *bf, size_t bit)
+{
+       if (bit >= bf->max_bits)
+               return;
+       bf->bits[bit / 8] |= BIT(bit % 8);
+}
+
+
+void bitfield_clear(struct bitfield *bf, size_t bit)
+{
+       if (bit >= bf->max_bits)
+               return;
+       bf->bits[bit / 8] &= ~BIT(bit % 8);
+}
+
+
+int bitfield_is_set(struct bitfield *bf, size_t bit)
+{
+       if (bit >= bf->max_bits)
+               return 0;
+       return !!(bf->bits[bit / 8] & BIT(bit % 8));
+}
+
+
+static int first_zero(u8 val)
+{
+       int i;
+       for (i = 0; i < 8; i++) {
+               if (!(val & 0x01))
+                       return i;
+               val >>= 1;
+       }
+       return -1;
+}
+
+
+int bitfield_get_first_zero(struct bitfield *bf)
+{
+       size_t i;
+       for (i = 0; i < (bf->max_bits + 7) / 8; i++) {
+               if (bf->bits[i] != 0xff)
+                       break;
+       }
+       if (i == (bf->max_bits + 7) / 8)
+               return -1;
+       i = i * 8 + first_zero(bf->bits[i]);
+       if (i >= bf->max_bits)
+               return -1;
+       return i;
+}