| #ifndef _OSMO_BITS_H |
| #define _OSMO_BITS_H |
| |
| #include <stdint.h> |
| |
| /*! \file bits.h |
| * \brief Osmocom bit level support code |
| */ |
| |
| typedef int8_t sbit_t; /*!< \brief soft bit (-127...127) */ |
| typedef uint8_t ubit_t; /*!< \brief unpacked bit (0 or 1) */ |
| typedef uint8_t pbit_t; /*!< \brief packed bis (8 bits in a byte) */ |
| |
| /* |
| NOTE on the endianess of pbit_t: |
| Bits in a pbit_t are ordered MSB first, i.e. 0x80 is the first bit. |
| Bit i in a pbit_t array is array[i/8] & (1<<(7-i%8)) |
| */ |
| |
| /*! \brief determine how many bytes we would need for \a num_bits packed bits |
| * \param[in] num_bits Number of packed bits |
| */ |
| static inline unsigned int osmo_pbit_bytesize(unsigned int num_bits) |
| { |
| unsigned int pbit_bytesize = num_bits / 8; |
| |
| if (num_bits % 8) |
| pbit_bytesize++; |
| |
| return pbit_bytesize; |
| } |
| |
| /*! \brief convert unpacked bits to packed bits, return length in bytes |
| * \param[out] out output buffer of packed bits |
| * \param[in] in input buffer of unpacked bits |
| * \param[in] num_bits number of bits |
| */ |
| int osmo_ubit2pbit(pbit_t *out, const ubit_t *in, unsigned int num_bits); |
| |
| /*! \brief convert packed bits to unpacked bits, return length in bytes |
| * \param[out] out output buffer of unpacked bits |
| * \param[in] in input buffer of packed bits |
| * \param[in] num_bits number of bits |
| */ |
| int osmo_pbit2ubit(ubit_t *out, const pbit_t *in, unsigned int num_bits); |
| |
| /*! \brief convert unpacked bits to packed bits (extended options) |
| * \param[out] out output buffer of packed bits |
| * \param[in] out_ofs offset into output buffer |
| * \param[in] in input buffer of unpacked bits |
| * \param[in] in_ofs offset into input buffer |
| * \param[in] num_bits number of bits |
| * \param[in] lsb_mode Encode bits in LSB orde instead of MSB |
| * \returns length in bytes (max written offset of output buffer + 1) |
| */ |
| int osmo_ubit2pbit_ext(pbit_t *out, unsigned int out_ofs, |
| const ubit_t *in, unsigned int in_ofs, |
| unsigned int num_bits, int lsb_mode); |
| |
| /*! \brief convert packed bits to unpacked bits (extended options) |
| * \param[out] out output buffer of unpacked bits |
| * \param[in] out_ofs offset into output buffer |
| * \param[in] in input buffer of packed bits |
| * \param[in] in_ofs offset into input buffer |
| * \param[in] num_bits number of bits |
| * \param[in] lsb_mode Encode bits in LSB orde instead of MSB |
| * \returns length in bytes (max written offset of output buffer + 1) |
| */ |
| int osmo_pbit2ubit_ext(ubit_t *out, unsigned int out_ofs, |
| const pbit_t *in, unsigned int in_ofs, |
| unsigned int num_bits, int lsb_mode); |
| |
| #endif |