libosmocore  0.9.3
Osmocom core library
bits.h
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1 #pragma once
2 
3 #include <stdint.h>
4 #include <stddef.h>
5 
6 #include <osmocom/core/bit16gen.h>
7 #include <osmocom/core/bit32gen.h>
8 #include <osmocom/core/bit64gen.h>
9 
18 typedef int8_t sbit_t;
19 typedef uint8_t ubit_t;
20 typedef uint8_t pbit_t;
22 /*
23  NOTE on the endianess of pbit_t:
24  Bits in a pbit_t are ordered MSB first, i.e. 0x80 is the first bit.
25  Bit i in a pbit_t array is array[i/8] & (1<<(7-i%8))
26 */
27 
31 static inline unsigned int osmo_pbit_bytesize(unsigned int num_bits)
32 {
33  unsigned int pbit_bytesize = num_bits / 8;
34 
35  if (num_bits % 8)
36  pbit_bytesize++;
37 
38  return pbit_bytesize;
39 }
40 
41 int osmo_ubit2pbit(pbit_t *out, const ubit_t *in, unsigned int num_bits);
42 
43 int osmo_pbit2ubit(ubit_t *out, const pbit_t *in, unsigned int num_bits);
44 
45 int osmo_ubit2pbit_ext(pbit_t *out, unsigned int out_ofs,
46  const ubit_t *in, unsigned int in_ofs,
47  unsigned int num_bits, int lsb_mode);
48 
49 int osmo_pbit2ubit_ext(ubit_t *out, unsigned int out_ofs,
50  const pbit_t *in, unsigned int in_ofs,
51  unsigned int num_bits, int lsb_mode);
52 
53 
54 /* BIT REVERSAL */
55 
66 };
67 
69 uint32_t osmo_bit_reversal(uint32_t x, enum osmo_br_mode k);
70 
71 /* \brief reverse the bits within each byte of a 32bit word */
72 uint32_t osmo_revbytebits_32(uint32_t x);
73 
74 /* \brief reverse the bits within a byte */
75 uint32_t osmo_revbytebits_8(uint8_t x);
76 
77 /* \brief reverse the bits of each byte in a given buffer */
78 void osmo_revbytebits_buf(uint8_t *buf, int len);
79 
85 static inline uint16_t osmo_rol16(uint16_t in, unsigned shift)
86 {
87  return (in << shift) | (in >> (16 - shift));
88 }
89 
int8_t sbit_t
soft bit (-127...127)
Definition: bits.h:18
reverse all bits in a 32bit dword
Definition: bits.h:59
int osmo_pbit2ubit(ubit_t *out, const pbit_t *in, unsigned int num_bits)
convert packed bits to unpacked bits, return length in bytes
Definition: bits.c:69
static uint16_t osmo_rol16(uint16_t in, unsigned shift)
left circular shift
Definition: bits.h:85
static unsigned int osmo_pbit_bytesize(unsigned int num_bits)
determine how many bytes we would need for num_bits packed bits
Definition: bits.h:31
int osmo_ubit2pbit(pbit_t *out, const ubit_t *in, unsigned int num_bits)
convert unpacked bits to packed bits, return length in bytes
Definition: bits.c:41
osmo_br_mode
bit-reversal mode for osmo_bit_reversal()
Definition: bits.h:57
reverse bits of each byte in a 32bit dword
Definition: bits.h:63
uint32_t osmo_bit_reversal(uint32_t x, enum osmo_br_mode k)
generic bit reversal function
Definition: bits.c:162
void osmo_revbytebits_buf(uint8_t *buf, int len)
reverse bit-order of each byte in a buffer
Definition: bits.c:209
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)
convert unpacked bits to packed bits (extended options)
Definition: bits.c:114
uint8_t pbit_t
packed bis (8 bits in a byte)
Definition: bits.h:20
uint32_t osmo_revbytebits_32(uint32_t x)
reverse the bit-order in each byte of a dword
Definition: bits.c:179
reverse byte order in a 32bit dword
Definition: bits.h:61
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)
convert packed bits to unpacked bits (extended options)
Definition: bits.c:139
uint8_t ubit_t
unpacked bit (0 or 1)
Definition: bits.h:19
swap the two 16bit words in a 32bit dword
Definition: bits.h:65
uint32_t osmo_revbytebits_8(uint8_t x)
reverse the bit order in a byte
Definition: bits.c:194