Huffman-Project/bitwriter.c at main · Abstract-Data-Type/Huffman-Project · GitHub

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#include <stdio.h>
#include <stdlib.h>
/* put in bitwriter.c */
#include "bitwriter.h"
#include "io.h"
struct BitWriter {
    Buffer *underlying_stream;
    uint8_t byte;
    uint8_t bit_position;
};

BitWriter *bit_write_open(const char *filename) {

    BitWriter *buf = calloc(1, sizeof(BitWriter));

    Buffer *underlying_stream = write_open(filename);

    buf->underlying_stream = underlying_stream;

    return buf;
}

void bit_write_close(BitWriter **pbuf) {

    if ((*pbuf)->bit_position > 0) {

        write_uint8((*pbuf)->underlying_stream, (*pbuf)->byte);
    }

    write_close(&(*pbuf)->underlying_stream);
    free(*pbuf);
    *pbuf = NULL;
}

void bit_write_bit(BitWriter *buf, uint8_t x) {

    if (buf->bit_position > 7) {

        write_uint8(buf->underlying_stream, buf->byte);
        buf->byte = 0x00;
        buf->bit_position = 0;
    }

    if (x & 1) {

        buf->byte |= (x & 1) << buf->bit_position;
    }

    buf->bit_position++;
}

void bit_write_uint8(BitWriter *buf, uint8_t x) {

    for (int i = 0; i <= 7; i++) {
        bit_write_bit(buf, x >> i);
    }
}

void bit_write_uint16(BitWriter *buf, uint16_t x) {

    for (int i = 0; i <= 15; i++) {
        bit_write_bit(buf, x >> i);
    }
}

void bit_write_uint32(BitWriter *buf, uint32_t x) {

    for (int i = 0; i <= 31; i++) {
        bit_write_bit(buf, x >> i);
    }
}