Harald Welte | 2230c13 | 2011-01-19 10:10:16 +0100 | [diff] [blame] | 1 | |
| 2 | #include <stdint.h> |
| 3 | |
Pablo Neira Ayuso | 8341934 | 2011-03-22 16:36:13 +0100 | [diff] [blame] | 4 | #include <osmocom/core/bits.h> |
Harald Welte | 2230c13 | 2011-01-19 10:10:16 +0100 | [diff] [blame] | 5 | |
| 6 | /* convert unpacked bits to packed bits, return length in bytes */ |
| 7 | int osmo_ubit2pbit(pbit_t *out, const ubit_t *in, unsigned int num_bits) |
| 8 | { |
| 9 | unsigned int i; |
| 10 | uint8_t curbyte = 0; |
| 11 | pbit_t *outptr = out; |
| 12 | |
| 13 | for (i = 0; i < num_bits; i++) { |
| 14 | uint8_t bitnum = 7 - (i % 8); |
| 15 | |
| 16 | curbyte |= (in[i] << bitnum); |
| 17 | |
Christian Vogel | c7f84e9 | 2011-01-22 22:48:37 +0100 | [diff] [blame] | 18 | if(i % 8 == 7){ |
Harald Welte | 2230c13 | 2011-01-19 10:10:16 +0100 | [diff] [blame] | 19 | *outptr++ = curbyte; |
| 20 | curbyte = 0; |
| 21 | } |
| 22 | } |
| 23 | /* we have a non-modulo-8 bitcount */ |
| 24 | if (i % 8) |
| 25 | *outptr++ = curbyte; |
| 26 | |
| 27 | return outptr - out; |
| 28 | } |
| 29 | |
| 30 | /* convert packed bits to unpacked bits, return length in bytes */ |
| 31 | int osmo_pbit2ubit(ubit_t *out, const pbit_t *in, unsigned int num_bits) |
| 32 | { |
| 33 | unsigned int i; |
| 34 | ubit_t *cur = out; |
| 35 | ubit_t *limit = out + num_bits; |
| 36 | |
| 37 | for (i = 0; i < (num_bits/8)+1; i++) { |
| 38 | pbit_t byte = in[i]; |
| 39 | *cur++ = (byte >> 7) & 1; |
| 40 | if (cur >= limit) |
| 41 | break; |
| 42 | *cur++ = (byte >> 6) & 1; |
| 43 | if (cur >= limit) |
| 44 | break; |
| 45 | *cur++ = (byte >> 5) & 1; |
| 46 | if (cur >= limit) |
| 47 | break; |
| 48 | *cur++ = (byte >> 4) & 1; |
| 49 | if (cur >= limit) |
| 50 | break; |
| 51 | *cur++ = (byte >> 3) & 1; |
| 52 | if (cur >= limit) |
| 53 | break; |
| 54 | *cur++ = (byte >> 2) & 1; |
| 55 | if (cur >= limit) |
| 56 | break; |
| 57 | *cur++ = (byte >> 1) & 1; |
| 58 | if (cur >= limit) |
| 59 | break; |
| 60 | *cur++ = (byte >> 0) & 1; |
| 61 | if (cur >= limit) |
| 62 | break; |
| 63 | } |
| 64 | return cur - out; |
| 65 | } |
Sylvain Munaut | aeb1077 | 2011-01-21 12:22:30 +0100 | [diff] [blame] | 66 | |
| 67 | /* convert unpacked bits to packed bits (extended options but slower), |
| 68 | * return length in bytes (max written ofs of output buffer + 1) */ |
| 69 | int osmo_ubit2pbit_ext(pbit_t *out, unsigned int out_ofs, |
| 70 | const ubit_t *in, unsigned int in_ofs, |
| 71 | unsigned int num_bits, int lsb_mode) |
| 72 | { |
| 73 | int i, op, bn; |
| 74 | for (i=0; i<num_bits; i++) { |
| 75 | op = out_ofs + i; |
| 76 | bn = lsb_mode ? (op&7) : (7-(op&7)); |
| 77 | if (in[in_ofs+i]) |
| 78 | out[op>>3] |= 1 << bn; |
| 79 | else |
| 80 | out[op>>3] &= ~(1 << bn); |
| 81 | } |
| 82 | return ((out_ofs + num_bits - 1) >> 3) + 1; |
| 83 | } |
| 84 | |
| 85 | /* convert packed bits to unpacked bits (extended options but slower), |
| 86 | * return length in bytes (max written ofs of output buffer + 1) */ |
| 87 | int osmo_pbit2ubit_ext(ubit_t *out, unsigned int out_ofs, |
| 88 | const pbit_t *in, unsigned int in_ofs, |
| 89 | unsigned int num_bits, int lsb_mode) |
| 90 | { |
| 91 | int i, ip, bn; |
| 92 | for (i=0; i<num_bits; i++) { |
| 93 | ip = in_ofs + i; |
| 94 | bn = lsb_mode ? (ip&7) : (7-(ip&7)); |
| 95 | out[out_ofs+i] = !!(in[ip>>3] & (1<<bn)); |
| 96 | } |
| 97 | return out_ofs + num_bits; |
| 98 | } |