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/* This file is part of the program psim.
Copyright (C) 1994-1995, Andrew Cagney <cagney@highland.com.au>
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 _ENDIAN_H_
#define _ENDIAN_H_
/* C byte conversion functions */
extern unsigned_1 endian_h2t_1(unsigned_1 x);
extern unsigned_2 endian_h2t_2(unsigned_2 x);
extern unsigned_4 endian_h2t_4(unsigned_4 x);
extern unsigned_8 endian_h2t_8(unsigned_8 x);
extern unsigned_1 endian_t2h_1(unsigned_1 x);
extern unsigned_2 endian_t2h_2(unsigned_2 x);
extern unsigned_4 endian_t2h_4(unsigned_4 x);
extern unsigned_8 endian_t2h_8(unsigned_8 x);
/* Host dependant:
The CPP below defines information about the compilation host. In
particular it defines the macro's:
WITH_HOST_BYTE_ORDER The byte order of the host. Could
be any of LITTLE_ENDIAN, BIG_ENDIAN
or 0 (unknown). Those macro's also
need to be defined.
WITH_NTOH Network byte order macros defined.
Possible value is 32 or (maybe one
day 64 because some 64bit network
byte order macro is defined.
*/
/* NetBSD:
NetBSD is easy, everything you could ever want is in a header file
(well almost :-) */
#if defined(__NetBSD__)
# include <machine/endian.h>
# define WITH_NTOH 32 /* what about alpha? */
# if (WITH_HOST_BYTE_ORDER == 0)
# undef WITH_HOST_BYTE_ORDER
# define WITH_HOST_BYTE_ORDER BYTE_ORDER
# endif
# if (BYTE_ORDER != WITH_HOST_BYTE_ORDER)
# error "host endian incorrectly configured, check config.h"
# endif
#endif
/* Linux is similarly easy. */
#if defined(__linux__)
# include <endian.h>
# include <asm/byteorder.h>
# if defined(__LITTLE_ENDIAN) && !defined(LITTLE_ENDIAN)
# define LITTLE_ENDIAN __LITTLE_ENDIAN
# endif
# if defined(__BIG_ENDIAN) && !defined(BIG_ENDIAN)
# define BIG_ENDIAN __BIG_ENDIAN
# endif
# if defined(__BYTE_ORDER) && !defined(BYTE_ORDER)
# define BYTE_ORDER __BYTE_ORDER
# endif
# if !defined(__alpha__)
# define WITH_NTOH 32 /* what about alpha? */
# endif
# if (WITH_HOST_BYTE_ORDER == 0)
# undef WITH_HOST_BYTE_ORDER
# define WITH_HOST_BYTE_ORDER BYTE_ORDER
# endif
# if (BYTE_ORDER != WITH_HOST_BYTE_ORDER)
# error "host endian incorrectly configured, check config.h"
# endif
#endif
/* INSERT HERE - hosts that have available LITTLE_ENDIAN and
BIG_ENDIAN macro's */
/* Some hosts don't define LITTLE_ENDIAN or BIG_ENDIAN, help them out */
#ifndef LITTLE_ENDIAN
#define LITTLE_ENDIAN 1234
#endif
#ifndef BIG_ENDIAN
#define BIG_ENDIAN 4321
#endif
/* SunOS on SPARC:
Big endian last time I looked */
#if defined(sparc) || defined(__sparc__)
# if (WITH_HOST_BYTE_ORDER == 0)
# undef WITH_HOST_BYTE_ORDER
# define WITH_HOST_BYTE_ORDER BIG_ENDIAN
# endif
# if (WITH_HOST_BYTE_ORDER != BIG_ENDIAN)
# error "sun was big endian last time I looked ..."
# endif
#endif
/* Random x86
Little endian last time I looked */
#if defined(i386) || defined(i486) || defined(i586) || defined(__i386__) || defined(__i486__) || defined(__i586__)
# if (WITH_HOST_BYTE_ORDER == 0)
# undef WITH_HOST_BYTE_ORDER
# define WITH_HOST_BYTE_ORDER LITTLE_ENDIAN
# endif
# if (WITH_HOST_BYTE_ORDER != LITTLE_ENDIAN)
# error "x86 was little endian last time I looked ..."
# endif
#endif
/* INSERT HERE - additional hosts that do not have LITTLE_ENDIAN and
BIG_ENDIAN definitions available. */
/* SWAPPING:
According to the following table:
TARG BE TARG LE TARG ??
HOST BE ok s/w s/w
HOST LE htohl ok ok|ntohl
HOST ?? ntohl s/w s/w
define host <-> target byte order conversion macro's */
/* IN PLACE:
These macro's given a variable argument swap its value in place if
so required */
#define H2T(VARIABLE) \
do { \
switch (sizeof(VARIABLE)) { \
case 1: VARIABLE = H2T_1(VARIABLE); break; \
case 2: VARIABLE = H2T_2(VARIABLE); break; \
case 4: VARIABLE = H2T_4(VARIABLE); break; \
case 8: VARIABLE = H2T_8(VARIABLE); break; \
} \
} while (0)
#define T2H(VARIABLE) \
do { \
switch (sizeof(VARIABLE)) { \
case 1: VARIABLE = T2H_1(VARIABLE); break; \
case 2: VARIABLE = T2H_2(VARIABLE); break; \
case 4: VARIABLE = T2H_4(VARIABLE); break; \
case 8: VARIABLE = T2H_8(VARIABLE); break; \
} \
} while (0)
/* TARGET WORD:
Byte swap a quantity the size of the targets word */
#if WITH_64BIT_TARGET
#define H2T_word(X) H2T_8(X)
#define T2H_word(X) T2H_8(X)
#else
#define H2T_word(X) H2T_4(X)
#define T2H_word(X) T2H_4(X)
#endif
/* FUNCTIONS:
Returns the value swapped according to the host/target byte order */
/* no need to swap */
#if 0
#if (WITH_HOST_BYTE_ORDER \
&& WITH_TARGET_BYTE_ORDER \
&& WITH_HOST_BYTE_ORDER == WITH_TARGET_BYTE_ORDER )
#define H2T_1(X) (X)
#define H2T_2(X) (X)
#define H2T_4(X) (X)
#define H2T_8(X) (X)
#define T2H_1(X) (X)
#define T2H_2(X) (X)
#define T2H_4(X) (X)
#define T2H_8(X) (X)
#endif
/* have ntoh and big endian target */
#if (WITH_TARGET_BYTE_ORDER == BIG_ENDIAN \
&& WITH_HOST_BYTE_ORDER != BIG_ENDIAN \
&& WITH_NTOH)
#define H2T_8(X) endian_h2t_8(X)
#define H2T_4(X) htonl(X)
#define H2T_2(X) htons(X)
#define H2T_1(X) (X)
#define T2H_8(X) endian_t2h_8(X)
#define T2H_4(X) htonl(X)
#define T2H_2(X) htons(X)
#define T2H_1(X) (X)
#endif
/* have ntoh, little host and unknown target */
#if (WITH_HOST_BYTE_ORDER == LITTLE_ENDIAN \
&& WITH_TARGET_BYTE_ORDER == 0 \
&& WITH_NTOH)
#define H2T_8(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : endian_h2t_8(X))
#define H2T_4(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htonl(X))
#define H2T_2(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htons(X))
#define H2T_1(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : (X))
#define T2H_8(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : endian_t2h_8(X))
#define T2H_4(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htonl(X))
#define T2H_2(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htons(X))
#define T2H_1(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : (X))
#endif
#endif
/* if all else fails use software */
#ifndef H2T_1
#define H2T_1(X) (X)
#define H2T_2(X) endian_h2t_2(X)
#define H2T_4(X) endian_h2t_4(X)
#define H2T_8(X) endian_h2t_8(X)
#define T2H_1(X) (X)
#define T2H_2(X) endian_t2h_2(X)
#define T2H_4(X) endian_t2h_4(X)
#define T2H_8(X) endian_t2h_8(X)
#endif
#endif
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