/*
 * Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation
 *
 * Author: Nikos Mavroyanopoulos
 *
 * This file is part of GNUTLS.
 *
 * The GNUTLS library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
 * USA
 *
 */

/* This file contains the functions needed for 64 bit integer support in
 * TLS, and functions which ease the access to TLS vectors (data of given size).
 */

#include <gnutls_int.h>
#include <gnutls_num.h>
#include <gnutls_errors.h>

/* This function will add one to uint64 x.
 * Returns 0 on success, or -1 if the uint64 max limit
 * has been reached.
 */
int _gnutls_uint64pp(uint64 * x)
{
    register int i, y = 0;

    for (i = 7; i >= 0; i--) {
	y = 0;
	if (x->i[i] == 0xff) {
	    x->i[i] = 0;
	    y = 1;
	} else
	    x->i[i]++;

	if (y == 0)
	    break;
    }
    if (y != 0)
	return -1;		/* over 64 bits! WOW */

    return 0;
}

uint32 _gnutls_uint24touint32(uint24 num)
{
    uint32 ret = 0;

    ((uint8 *) & ret)[1] = num.pint[0];
    ((uint8 *) & ret)[2] = num.pint[1];
    ((uint8 *) & ret)[3] = num.pint[2];
    return ret;
}

uint24 _gnutls_uint32touint24(uint32 num)
{
    uint24 ret;

    ret.pint[0] = ((uint8 *) & num)[1];
    ret.pint[1] = ((uint8 *) & num)[2];
    ret.pint[2] = ((uint8 *) & num)[3];
    return ret;

}

/* data should be at least 3 bytes */
uint32 _gnutls_read_uint24(const opaque * data)
{
    uint32 res;
    uint24 num;

    num.pint[0] = data[0];
    num.pint[1] = data[1];
    num.pint[2] = data[2];

    res = _gnutls_uint24touint32(num);
#ifndef WORDS_BIGENDIAN
    res = byteswap32(res);
#endif
    return res;
}

void _gnutls_write_uint24(uint32 num, opaque * data)
{
    uint24 tmp;

#ifndef WORDS_BIGENDIAN
    num = byteswap32(num);
#endif
    tmp = _gnutls_uint32touint24(num);

    data[0] = tmp.pint[0];
    data[1] = tmp.pint[1];
    data[2] = tmp.pint[2];
}

uint32 _gnutls_read_uint32(const opaque * data)
{
    uint32 res;

    memcpy(&res, data, sizeof(uint32));
#ifndef WORDS_BIGENDIAN
    res = byteswap32(res);
#endif
    return res;
}

void _gnutls_write_uint32(uint32 num, opaque * data)
{

#ifndef WORDS_BIGENDIAN
    num = byteswap32(num);
#endif
    memcpy(data, &num, sizeof(uint32));
}

uint16 _gnutls_read_uint16(const opaque * data)
{
    uint16 res;
    memcpy(&res, data, sizeof(uint16));
#ifndef WORDS_BIGENDIAN
    res = byteswap16(res);
#endif
    return res;
}

void _gnutls_write_uint16(uint16 num, opaque * data)
{

#ifndef WORDS_BIGENDIAN
    num = byteswap16(num);
#endif
    memcpy(data, &num, sizeof(uint16));
}

uint32 _gnutls_conv_uint32(uint32 data)
{
#ifndef WORDS_BIGENDIAN
    return byteswap32(data);
#else
    return data;
#endif
}

uint16 _gnutls_conv_uint16(uint16 data)
{
#ifndef WORDS_BIGENDIAN
    return byteswap16(data);
#else
    return data;
#endif
}

uint32 _gnutls_uint64touint32(const uint64 * num)
{
    uint32 ret;

    memcpy(&ret, &num->i[4], 4);
#ifndef WORDS_BIGENDIAN
    ret = byteswap32(ret);
#endif

    return ret;
}