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#include <bitfield/bitfield.h>
#include <limits.h>
#include <string.h>
#include <stddef.h>
#include <endian.h>
uint64_t bitmask(const uint8_t bit_count) {
return (((uint64_t)0x1) << bit_count) - 1;
}
uint8_t get_nibble(const uint8_t source[], const uint8_t source_length,
const uint8_t nibble_index) {
uint8_t byte_index = nibble_index / 2;
uint8_t result = get_byte(source, source_length, byte_index);
if(nibble_index % 2 == 0) {
result >>= NIBBLE_SIZE;
}
result &= bitmask(NIBBLE_SIZE);
return result;
}
uint8_t get_byte(const uint8_t source[], const uint8_t source_length,
const uint8_t byte_index) {
if(byte_index < source_length) {
return source[byte_index];
}
return 0;
}
uint64_t get_bitfield(const uint8_t source[], const uint8_t source_length,
const uint16_t offset, const uint16_t bit_count) {
if(bit_count > 64 || bit_count < 1) {
// TODO error reporting?
return 0;
}
union {
uint64_t whole;
uint8_t bytes[sizeof(uint64_t)];
} combined;
copy_bits_right_aligned(source, source_length, offset, bit_count,
combined.bytes, sizeof(combined.bytes));
return htobe64(combined.whole);
}
bool set_nibble(const uint16_t nibble_index, const uint8_t value,
uint8_t* destination, const uint16_t destination_length) {
return copy_bits(&value, CHAR_BIT, NIBBLE_SIZE, NIBBLE_SIZE, destination,
destination_length, nibble_index * NIBBLE_SIZE);
}
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