diff options
Diffstat (limited to 'src/bitvec.c')
| -rw-r--r-- | src/bitvec.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/src/bitvec.c b/src/bitvec.c index eb83ac66..04c465a8 100644 --- a/src/bitvec.c +++ b/src/bitvec.c @@ -77,6 +77,25 @@ enum bit_value bitvec_get_bit_pos(const struct bitvec *bv, unsigned int bitnr) return ZERO; } +/* check if the bit is L or H for a given position inside a bitvec */ +enum bit_value bitvec_get_bit_pos_high(const 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(H, bitnum); + + if (bv->data[bytenum] & bitval) + return H; + + return L; +} + /* get the Nth set bit inside the bit vector */ unsigned int bitvec_get_nth_set_bit(const struct bitvec *bv, unsigned int n) { @@ -127,6 +146,18 @@ int bitvec_set_bit(struct bitvec *bv, enum bit_value bit) return rc; } +/* get the next bit (low/high) inside a bitvec */ +int bitvec_get_bit_high(struct bitvec *bv) +{ + int rc; + + rc = bitvec_get_bit_pos_high(bv, bv->cur_bit); + if (rc >= 0) + 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) { @@ -158,6 +189,24 @@ int bitvec_set_uint(struct bitvec *bv, unsigned int ui, int num_bits) return 0; } +/* get multiple bits (based on numeric value) from current pos */ +int bitvec_get_uint(struct bitvec *bv, int num_bits) +{ + int i; + unsigned int ui = 0; + + for (i = 0; i < num_bits; i++) { + int bit = bitvec_get_bit_pos(bv, bv->cur_bit); + if (bit < 0) + return bit; + if (bit) + ui |= (1 << (num_bits - i - 1)); + bv->cur_bit++; + } + + return ui; +} + /* pad all remaining bits up to num_bits */ int bitvec_spare_padding(struct bitvec *bv, unsigned int up_to_bit) { |