FQRb - MPEG1 Overwrite

#include <cstdio>
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <sys/stat.h>

const unsigned char audioSequence[] =
{
    0, 0, 1, 0xC0
};

const char  fileName[]  = "OPENING.SFD",
            audioName[] = "OPENING.ADX";
uint32_t    fileSize, audioOffset   = 0;
FILE        *audioFp;

/* Function to open a file in read mode.
 */
FILE *getFile(const char *filename)
{
    FILE    *fp = fopen(filename, "r+");
    if  (fp == nullptr) exit(0);
    return  fp;
}

/* Function to get file size.
 */
unsigned int getSize(FILE *fp)
{
    struct  stat st;
    fstat(  fileno(fp), &st);
    return  st.st_size;
}

/* Function that will replace an ADX block
 * with its equivalent from another file.
 */
void replaceAudio(FILE *fp, uint32_t packsize)
{
    uint8_t *data = new uint8_t[packsize];
    fseek(fp, 4 + 2 + 7 - 6, SEEK_CUR);
    fread(data, packsize, 1, audioFp);
    fwrite(data, packsize, 1, fp);
    delete[] data;
}

/* Simple function to locate an
 * arbitrary byte sequence in a
 * file.
 */
void searchSequence(FILE *fp, int currentOffset)
{
    unsigned char currentSequence[6] = { 0 };
    unsigned int  packSize;

    fseek(fp, currentOffset, SEEK_SET);
    fread(&currentSequence, sizeof currentSequence, 1, fp);
    packSize = (currentSequence[4] << 8) | currentSequence[5];

    if( !memcmp(
    audioSequence,
    currentSequence,
    sizeof audioSequence
    ) && packSize <= 0x07E7)
    {
        replaceAudio(fp, packSize - 7);
    }
}

int main()
{
    audioFp  = getFile(audioName);
    FILE *fp = getFile(fileName);
    fileSize = getSize(fp);

    // ¯\_(ツ)_/¯
    for( unsigned int i = 0; i < fileSize - 4 - 1; i++)
        searchSequence(fp, i);

    return 0;
}