Method writeNextCluster

src/core/FatSystem.cpp:264–306

* Changes the next cluster in a file */

 * Changes the next cluster in a file
 */
bool FatSystem::writeNextCluster(unsigned int cluster, unsigned int next, int fat)
{
    int bytes = (bits == 32 ? 4 : 2);
#ifndef __WIN__
    char buffer[bytes];
#else
        char *buffer = new char[bytes];
        __try
        {
#endif

    if (!validCluster(cluster)) {
        throw string("Trying to access a cluster outside bounds");
    }

    int offset = fatStart+fatSize*fat+(bits*cluster)/8;

    if (bits == 12) {
        readData(offset, buffer, bytes);
        int bit = cluster*bits;

        if (bit%8 != 0) {
            buffer[0] = ((next&0x0f)<<4)|(buffer[0]&0x0f);
            buffer[1] = (next>>4)&0xff;
        } else {
            buffer[0] = next&0xff;
            buffer[1] = (buffer[1]&0xf0)|((next>>8)&0x0f);
        }
    } else {
        for (int i=0; i<(bits/8); i++) {
            buffer[i] = (next>>(8*i))&0xff;
        }
    }

    return writeData(offset, buffer, bytes) == bytes;
#ifdef __WIN__
}
__finally
{
    delete[] buffer;
}
#endif
}

bool FatSystem::validCluster(unsigned int cluster)
{