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Refactor the concatbits function to support both MSB and LSB first src

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douniwan5788 2025-03-15 03:54:52 +08:00
commit d13e7b0b64
5 changed files with 41 additions and 32 deletions
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12
common/commonutil.c
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@ -555,9 +555,13 @@ void reverse_arraybytes_copy(uint8_t *arr, uint8_t *dest, size_t len) {
}
// TODO: Boost performance by copying in chunks of 1, 2, or 4 bytes when feasible.
size_t concatbits(uint8_t *dest, int dest_offset, const uint8_t *src, int src_offset, size_t nbits) {
/**
* @brief Concatenate bits from src to dest, bitstream is stored MSB first
* which means that the dest_offset=0 is the MSB of the dest[0]
*
*/
size_t concatbits(uint8_t *dest, int dest_offset, const uint8_t *src, int src_offset, size_t nbits, bool src_lsb) {
int i, end, step;
// overlap
if ((src - dest) * 8 + src_offset - dest_offset > 0) {
i = 0;
@ -571,8 +575,8 @@ size_t concatbits(uint8_t *dest, int dest_offset, const uint8_t *src, int src_of
for (; i != end; i += step) {
// equiv of dest_bits[dest_offset + i] = src_bits[src_offset + i]
CLEAR_BIT(dest, dest_offset + i);
if (TEST_BIT(src, src_offset + i)) SET_BIT(dest, dest_offset + i);
CLEAR_BIT_MSB(dest, dest_offset + i);
if (src_lsb ? TEST_BIT_LSB(src, src_offset + i) : TEST_BIT_MSB(src, src_offset + i)) SET_BIT_MSB(dest, dest_offset + i);
}
return dest_offset + nbits;

2
common/commonutil.h
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@ -150,7 +150,7 @@ bool hexstr_to_byte_array(const char *hexstr, uint8_t *d, size_t *n);
void reverse_arraybytes(uint8_t *arr, size_t len);
void reverse_arraybytes_copy(uint8_t *arr, uint8_t *dest, size_t len);
size_t concatbits(uint8_t *dest, int dest_offset, const uint8_t *src, int src_offset, size_t nbits);
size_t concatbits(uint8_t *dest, int dest_offset, const uint8_t *src, int src_offset, size_t nbits, bool src_lsb);
int char2int(char c);
int hexstr2ByteArr(const char *hexstr, unsigned char *array, size_t asize);
#endif