intial checkin of the libosmocore project
diff --git a/src/bitvec.c b/src/bitvec.c
new file mode 100644
index 0000000..235c3ce
--- /dev/null
+++ b/src/bitvec.c
@@ -0,0 +1,170 @@
+/* bit vector utility routines */
+
+/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+
+#include <errno.h>
+#include <stdint.h>
+
+#include <osmocore/bitvec.h>
+
+#define BITNUM_FROM_COMP(byte, bit) ((byte*8)+bit)
+
+static inline unsigned int bytenum_from_bitnum(unsigned int bitnum)
+{
+ unsigned int bytenum = bitnum / 8;
+
+ return bytenum;
+}
+
+/* convert ZERO/ONE/L/H to a bitmask at given pos in a byte */
+static uint8_t bitval2mask(enum bit_value bit, uint8_t bitnum)
+{
+ int bitval;
+
+ switch (bit) {
+ case ZERO:
+ bitval = (0 << bitnum);
+ break;
+ case ONE:
+ bitval = (1 << bitnum);
+ break;
+ case L:
+ bitval = ((0x2b ^ (0 << bitnum)) & (1 << bitnum));
+ break;
+ case H:
+ bitval = ((0x2b ^ (1 << bitnum)) & (1 << bitnum));
+ break;
+ default:
+ return 0;
+ }
+ return bitval;
+}
+
+/* check if the bit is 0 or 1 for a given position inside a bitvec */
+enum bit_value bitvec_get_bit_pos(struct bitvec *bv, unsigned int bitnr)
+{
+ unsigned int bytenum = bytenum_from_bitnum(bitnr);
+ unsigned int bitnum = 7 - (bitnr % 8);
+ uint8_t bitval;
+
+ if (bytenum >= bv->data_len)
+ return -EINVAL;
+
+ bitval = bitval2mask(ONE, bitnum);
+
+ if (bv->data[bytenum] & bitval)
+ return ONE;
+
+ return ZERO;
+}
+
+/* get the Nth set bit inside the bit vector */
+unsigned int bitvec_get_nth_set_bit(struct bitvec *bv, unsigned int n)
+{
+ unsigned int i, k = 0;
+
+ for (i = 0; i < bv->data_len*8; i++) {
+ if (bitvec_get_bit_pos(bv, i) == ONE) {
+ k++;
+ if (k == n)
+ return i;
+ }
+ }
+
+ return 0;
+}
+
+/* set the bit at a given position inside a bitvec */
+int bitvec_set_bit_pos(struct bitvec *bv, unsigned int bitnr,
+ enum bit_value bit)
+{
+ unsigned int bytenum = bytenum_from_bitnum(bitnr);
+ unsigned int bitnum = 7 - (bitnr % 8);
+ uint8_t bitval;
+
+ if (bytenum >= bv->data_len)
+ return -EINVAL;
+
+ /* first clear the bit */
+ bitval = bitval2mask(ONE, bitnum);
+ bv->data[bytenum] &= ~bitval;
+
+ /* then set it to desired value */
+ bitval = bitval2mask(bit, bitnum);
+ bv->data[bytenum] |= bitval;
+
+ return 0;
+}
+
+/* set the next bit inside a bitvec */
+int bitvec_set_bit(struct bitvec *bv, enum bit_value bit)
+{
+ int rc;
+
+ rc = bitvec_set_bit_pos(bv, bv->cur_bit, bit);
+ if (!rc)
+ bv->cur_bit++;
+
+ return rc;
+}
+
+/* set multiple bits (based on array of bitvals) at current pos */
+int bitvec_set_bits(struct bitvec *bv, enum bit_value *bits, int count)
+{
+ int i, rc;
+
+ for (i = 0; i < count; i++) {
+ rc = bitvec_set_bit(bv, bits[i]);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
+/* set multiple bits (based on numeric value) at current pos */
+int bitvec_set_uint(struct bitvec *bv, unsigned int ui, int num_bits)
+{
+ int i, rc;
+
+ for (i = 0; i < num_bits; i++) {
+ int bit = 0;
+ if (ui & (1 << (num_bits - i - 1)))
+ bit = 1;
+ rc = bitvec_set_bit(bv, bit);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
+/* pad all remaining bits up to num_bits */
+int bitvec_spare_padding(struct bitvec *bv, unsigned int up_to_bit)
+{
+ unsigned int i;
+
+ for (i = bv->cur_bit; i <= up_to_bit; i++)
+ bitvec_set_bit(bv, L);
+
+ return 0;
+}