diff options
| author | Jacob Erlbeck <jerlbeck@sysmocom.de> | 2015-12-21 16:04:03 +0100 |
|---|---|---|
| committer | Holger Hans Peter Freyther <holger@moiji-mobile.com> | 2016-01-15 14:51:32 +0100 |
| commit | 5f349be820b32a5bb312566a4a35ef679fe7e478 (patch) | |
| tree | 4e5c9a197c485d3481aa8b9ed559582708c7ffb6 /include | |
| parent | 8114294bf29ac6e44822c0ae43d4b0819f11b022 (diff) | |
bitvec: Add get/set byte sequences
The new functions bitvec_get_bytes and bitvec_set_bytes copy
byte sequences from bitvecs to uint8_t arrays and vice versa.
While the bytes in the bitvecs do not need to be aligned, the uint8_t
arrays always are. In case the bytes in the bitvec are aligned, the
implementation uses memcpy.
Note that the implementation like the other existing functions assume
MSB first encoding.
[hfreyther: Squash the comment fix into this commit as well]
Sponsored-by: On-Waves ehf
Diffstat (limited to 'include')
| -rw-r--r-- | include/osmocom/core/bitvec.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/osmocom/core/bitvec.h b/include/osmocom/core/bitvec.h index 62e2e7b6..89eb7848 100644 --- a/include/osmocom/core/bitvec.h +++ b/include/osmocom/core/bitvec.h @@ -28,6 +28,14 @@ /*! \file bitvec.h * \brief Osmocom bit vector abstraction + * + * These functions assume a MSB (most significant bit) first layout of the + * bits, so that for instance the 5 bit number abcde (a is MSB) can be + * embedded into a byte sequence like in xxxxxxab cdexxxxx. The bit count + * starts with the MSB, so the bits in a byte are numbered (MSB) 01234567 (LSB). + * Note that there are other incompatible encodings, like it is used + * for the EGPRS RLC data block headers (there the bits are numbered from LSB + * to MSB). */ #include <stdint.h> @@ -63,5 +71,7 @@ int bitvec_set_uint(struct bitvec *bv, unsigned int in, int count); int bitvec_get_uint(struct bitvec *bv, int num_bits); int bitvec_find_bit_pos(const struct bitvec *bv, unsigned int n, enum bit_value val); int bitvec_spare_padding(struct bitvec *bv, unsigned int up_to_bit); +int bitvec_get_bytes(struct bitvec *bv, uint8_t *bytes, int count); +int bitvec_set_bytes(struct bitvec *bv, const uint8_t *bytes, int count); /*! @} */ |