Modified version of lib3ds reader of .3ds format

#include "Lib3ds_io.h"

typedef union
{
    quint32 dword_value;
    float float_value;
} Lib3dsDwordFloat;

Lib3ds_io::Lib3ds_io()
{
}

qint64 Lib3ds_io::lib3ds_io_seek(qint64 offset, Lib3dsIoSeek origin)
{
    return fileio_seek_func(offset, origin);
}

qint64 Lib3ds_io::lib3ds_io_tell()
{
    return fileio_tell_func();
}

qint64 Lib3ds_io::lib3ds_io_read(void *buffer, qint64 size)
{
    return fileio_read_func(buffer, size);
}

qint64 Lib3ds_io::lib3ds_io_write(const void *buffer, qint64 size)
{
    return fileio_write_func(buffer, size);
}

/*!
 * Read a byte from a file stream.
 */
quint8 Lib3ds_io::lib3ds_io_read_byte()
{
    quint8 b;

    lib3ds_io_read(&b, 1);

    return(b);
}

/**
 * Read a word from a file stream in little endian format.
 */
quint16 Lib3ds_io::lib3ds_io_read_word()
{
    quint8 b[2];
    quint16 w;

    lib3ds_io_read(b, 2);
    w = ((quint16)b[1] << 8) |
        ((quint16)b[0]);
    return(w);
}

/*!
 * Read a dword from file a stream in little endian format.
 */
quint32 Lib3ds_io::lib3ds_io_read_dword()
{
    quint8 b[4];
    quint32 d;

    lib3ds_io_read(b, 4);
    d = ((quint32)b[3] << 24) |
        ((quint32)b[2] << 16) |
        ((quint32)b[1] << 8) |
        ((quint32)b[0]);
    return(d);
}

/*!
 * Read a signed byte from a file stream.
 */
qint8 Lib3ds_io::lib3ds_io_read_intb()
{
    qint8 b;

    lib3ds_io_read(&b, 1);
    return(b);
}

/*!
 * Read a signed word from a file stream in little endian format.
 */
qint16 Lib3ds_io::lib3ds_io_read_intw()
{
    quint8 b[2];
    quint16 w;

    lib3ds_io_read(b, 2);
    w = ((quint16)b[1] << 8) |
        ((quint16)b[0]);
    return((qint16)w);
}

/*!
 * Read a signed dword a from file stream in little endian format.
 */
qint32 Lib3ds_io::lib3ds_io_read_intd()
{
    quint8 b[4];
    quint32 d;

    lib3ds_io_read(b, 4);
    d = ((quint32)b[3] << 24) |
        ((quint32)b[2] << 16) |
        ((quint32)b[1] << 8) |
        ((quint32)b[0]);
    return((qint32)d);
}

/*!
 * Read a float from a file stream in little endian format.
 */
float Lib3ds_io::lib3ds_io_read_float()
{
    quint8 b[4];
    Lib3dsDwordFloat d;

    lib3ds_io_read(b, 4);
    d.dword_value = ((quint32)b[3] << 24) |
                    ((quint32)b[2] << 16) |
                    ((quint32)b[1] << 8) |
                    ((quint32)b[0]);
    return d.float_value;
}

/*!
 * Read a vector from a file stream in little endian format.
 *
 * \param io IO input handle.
 * \param v  The vector to store the data.
 */
void Lib3ds_io::lib3ds_io_read_vector(float v[3])
{
    v[0] = lib3ds_io_read_float();
    v[1] = lib3ds_io_read_float();
    v[2] = lib3ds_io_read_float();
}

void Lib3ds_io::lib3ds_io_read_rgb(float rgb[3])
{
    rgb[0] = lib3ds_io_read_float();
    rgb[1] = lib3ds_io_read_float();
    rgb[2] = lib3ds_io_read_float();
}

/*!
 * Read a zero-terminated string from a file stream.
 *
 * \param io      IO input handle.
 * \param s       The buffer to store the read string.
 * \param buflen  Buffer length.
 *
 * \return        True on success, False otherwise.
 */
bool Lib3ds_io::lib3ds_io_read_string(QString &s, int buflen)
{
    char c;
    int k = 0;

    s.clear();

    for (;;)
    {
        if (lib3ds_io_read(&c, 1) != 1)
        {
            return false;
        }

        if (!c)
        {
            break;
        }

        s += c;

        ++k;

        if (k >= buflen)
        {
            return false;
        }
    }

    return true;
}