diff options
author | Pablo Neira Ayuso <pablo@gnumonks.org> | 2011-04-26 00:28:18 +0200 |
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committer | Pablo Neira Ayuso <pablo@gnumonks.org> | 2011-04-26 00:28:18 +0200 |
commit | f0059596a20bfa406a500ca5d6b34bf88d333ed3 (patch) | |
tree | 41bc483077171529e20084ede0784dd6af076056 /src/shared/libosmocore/src/bits.c | |
parent | d9639bb010d05a96a6cbced94668c5754a4f0de9 (diff) | |
parent | 28dbfe9bf7a799ab1da2563fd5e007d007b54168 (diff) |
Merge commit '28dbfe9bf7a799ab1da2563fd5e007d007b54168'
Diffstat (limited to 'src/shared/libosmocore/src/bits.c')
-rw-r--r-- | src/shared/libosmocore/src/bits.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/src/shared/libosmocore/src/bits.c b/src/shared/libosmocore/src/bits.c new file mode 100644 index 00000000..ff5d176c --- /dev/null +++ b/src/shared/libosmocore/src/bits.c @@ -0,0 +1,98 @@ + +#include <stdint.h> + +#include <osmocom/core/bits.h> + +/* convert unpacked bits to packed bits, return length in bytes */ +int osmo_ubit2pbit(pbit_t *out, const ubit_t *in, unsigned int num_bits) +{ + unsigned int i; + uint8_t curbyte = 0; + pbit_t *outptr = out; + + for (i = 0; i < num_bits; i++) { + uint8_t bitnum = 7 - (i % 8); + + curbyte |= (in[i] << bitnum); + + if(i % 8 == 7){ + *outptr++ = curbyte; + curbyte = 0; + } + } + /* we have a non-modulo-8 bitcount */ + if (i % 8) + *outptr++ = curbyte; + + return outptr - out; +} + +/* convert packed bits to unpacked bits, return length in bytes */ +int osmo_pbit2ubit(ubit_t *out, const pbit_t *in, unsigned int num_bits) +{ + unsigned int i; + ubit_t *cur = out; + ubit_t *limit = out + num_bits; + + for (i = 0; i < (num_bits/8)+1; i++) { + pbit_t byte = in[i]; + *cur++ = (byte >> 7) & 1; + if (cur >= limit) + break; + *cur++ = (byte >> 6) & 1; + if (cur >= limit) + break; + *cur++ = (byte >> 5) & 1; + if (cur >= limit) + break; + *cur++ = (byte >> 4) & 1; + if (cur >= limit) + break; + *cur++ = (byte >> 3) & 1; + if (cur >= limit) + break; + *cur++ = (byte >> 2) & 1; + if (cur >= limit) + break; + *cur++ = (byte >> 1) & 1; + if (cur >= limit) + break; + *cur++ = (byte >> 0) & 1; + if (cur >= limit) + break; + } + return cur - out; +} + +/* convert unpacked bits to packed bits (extended options but slower), + * return length in bytes (max written ofs 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) +{ + int i, op, bn; + for (i=0; i<num_bits; i++) { + op = out_ofs + i; + bn = lsb_mode ? (op&7) : (7-(op&7)); + if (in[in_ofs+i]) + out[op>>3] |= 1 << bn; + else + out[op>>3] &= ~(1 << bn); + } + return ((out_ofs + num_bits - 1) >> 3) + 1; +} + +/* convert packed bits to unpacked bits (extended options but slower), + * return length in bytes (max written ofs 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) +{ + int i, ip, bn; + for (i=0; i<num_bits; i++) { + ip = in_ofs + i; + bn = lsb_mode ? (ip&7) : (7-(ip&7)); + out[out_ofs+i] = !!(in[ip>>3] & (1<<bn)); + } + return out_ofs + num_bits; +} |