/*
 * VARCem	Virtual ARchaeological Computer EMulator.
 *		An emulator of (mostly) x86-based PC systems and devices,
 *		using the ISA,EISA,VLB,MCA  and PCI system buses, roughly
 *		spanning the era between 1981 and 1995.
 *
 *		This file is part of the VARCem Project.
 *
 *		Various definitions for portable byte-swapping.
 *
 * Version:	@(#)bswap.h	1.0.2	2018/03/12
 *
 * Authors:	Fred N. van Kempen, <decwiz@yahoo.com>
 *		neozeed,
 *
 *		Copyright 2017,2018 Fred N. van Kempen.
 *		Copyright 2016-2018 neozeed.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free  Software  Foundation; either  version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the:
 *
 *   Free Software Foundation, Inc.
 *   59 Temple Place - Suite 330
 *   Boston, MA 02111-1307
 *   USA.
 */
#ifndef BSWAP_H
#define BSWAP_H

#include <stdint.h>

#ifdef HAVE_BYTESWAP_H
#include <byteswap.h>
#else
# define bswap_16(x) \
	( \
	    ((uint16_t)( \
		(((uint16_t)(x) & (uint16_t)0x00ffU) << 8) | \
		(((uint16_t)(x) & (uint16_t)0xff00U) >> 8) )) \
	)

# define bswap_32(x) \
	( \
	    ((uint32_t)( \
		(((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) | \
		(((uint32_t)(x) & (uint32_t)0x0000ff00UL) <<  8) | \
		(((uint32_t)(x) & (uint32_t)0x00ff0000UL) >>  8) | \
		(((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24) )) \
	)

# define bswap_64(x) \
	( \
	    ((uint64_t)( \
		(uint64_t)(((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) | \
		(uint64_t)(((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
		(uint64_t)(((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
		(uint64_t)(((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) <<  8) | \
	        (uint64_t)(((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >>  8) | \
		(uint64_t)(((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
		(uint64_t)(((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
		(uint64_t)(((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56) )) \
	)
#endif	/*HAVE_BYTESWAP_H*/

static __inline uint16_t bswap16(uint16_t x)
{
    return bswap_16(x);
}

static __inline uint32_t bswap32(uint32_t x)
{
    return bswap_32(x);
}

static __inline uint64_t bswap64(uint64_t x)
{
    return bswap_64(x);
}

static __inline void bswap16s(uint16_t *s)
{
    *s = bswap16(*s);
}

static __inline void bswap32s(uint32_t *s)
{
    *s = bswap32(*s);
}

static __inline void bswap64s(uint64_t *s)
{
    *s = bswap64(*s);
}

#if defined(WORDS_BIGENDIAN)
# define be_bswap(v, size) (v)
# define le_bswap(v, size) bswap ## size(v)
# define be_bswaps(v, size)
# define le_bswaps(p, size) *p = bswap ## size(*p);
#else
# define le_bswap(v, size) (v)
# define be_bswap(v, size) bswap ## size(v)
# define le_bswaps(v, size)
# define be_bswaps(p, size) *p = bswap ## size(*p);
#endif

#define CPU_CONVERT(endian, size, type)\
static __inline type endian ## size ## _to_cpu(type v)\
{\
    return endian ## _bswap(v, size);\
}\
\
static __inline type cpu_to_ ## endian ## size(type v)\
{\
    return endian ## _bswap(v, size);\
}\
\
static __inline void endian ## size ## _to_cpus(type *p)\
{\
    endian ## _bswaps(p, size)\
}\
\
static __inline void cpu_to_ ## endian ## size ## s(type *p)\
{\
    endian ## _bswaps(p, size)\
}\
\
static __inline type endian ## size ## _to_cpup(const type *p)\
{\
    return endian ## size ## _to_cpu(*p);\
}\
\
static __inline void cpu_to_ ## endian ## size ## w(type *p, type v)\
{\
     *p = cpu_to_ ## endian ## size(v);\
}

CPU_CONVERT(be, 16, uint16_t)
CPU_CONVERT(be, 32, uint32_t)
CPU_CONVERT(be, 64, uint64_t)

CPU_CONVERT(le, 16, uint16_t)
CPU_CONVERT(le, 32, uint32_t)
CPU_CONVERT(le, 64, uint64_t)

/* unaligned versions (optimized for frequent unaligned accesses)*/

#if defined(__i386__) || defined(__powerpc__)

#define cpu_to_le16wu(p, v) cpu_to_le16w(p, v)
#define cpu_to_le32wu(p, v) cpu_to_le32w(p, v)
#define le16_to_cpupu(p) le16_to_cpup(p)
#define le32_to_cpupu(p) le32_to_cpup(p)

#define cpu_to_be16wu(p, v) cpu_to_be16w(p, v)
#define cpu_to_be32wu(p, v) cpu_to_be32w(p, v)

#else

static __inline void cpu_to_le16wu(uint16_t *p, uint16_t v)
{
    uint8_t *p1 = (uint8_t *)p;

    p1[0] = v & 0xff;
    p1[1] = v >> 8;
}

static __inline void cpu_to_le32wu(uint32_t *p, uint32_t v)
{
    uint8_t *p1 = (uint8_t *)p;

    p1[0] = v;
    p1[1] = v >> 8;
    p1[2] = v >> 16;
    p1[3] = v >> 24;
}

static __inline uint16_t le16_to_cpupu(const uint16_t *p)
{
    const uint8_t *p1 = (const uint8_t *)p;
    return p1[0] | (p1[1] << 8);
}

static __inline uint32_t le32_to_cpupu(const uint32_t *p)
{
    const uint8_t *p1 = (const uint8_t *)p;
    return p1[0] | (p1[1] << 8) | (p1[2] << 16) | (p1[3] << 24);
}

static __inline void cpu_to_be16wu(uint16_t *p, uint16_t v)
{
    uint8_t *p1 = (uint8_t *)p;

    p1[0] = v >> 8;
    p1[1] = v & 0xff;
}

static __inline void cpu_to_be32wu(uint32_t *p, uint32_t v)
{
    uint8_t *p1 = (uint8_t *)p;

    p1[0] = v >> 24;
    p1[1] = v >> 16;
    p1[2] = v >> 8;
    p1[3] = v;
}

#endif

#ifdef WORDS_BIGENDIAN
#define cpu_to_32wu cpu_to_be32wu
#else
#define cpu_to_32wu cpu_to_le32wu
#endif

#undef le_bswap
#undef be_bswap
#undef le_bswaps
#undef be_bswaps

#endif /* BSWAP_H */
