/*
 * byteswap - byte swapping routines
 *
 * Copyright (C) 1999,2021,2022  Landon Curt Noll
 *
 * Calc is open software; you can redistribute it and/or modify it under
 * the terms of the version 2.1 of the GNU Lesser General Public License
 * as published by the Free Software Foundation.
 *
 * Calc 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.
 *
 * A copy of version 2.1 of the GNU Lesser General Public License is
 * distributed with calc under the filename COPYING-LGPL.  You should have
 * received a copy with calc; if not, write to Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Under source code control:	1995/10/11 04:44:01
 * File existed as early as:	1995
 *
 * chongo <was here> /\oo/\	http://www.isthe.com/chongo/
 * Share and enjoy!  :-)	http://www.isthe.com/chongo/tech/comp/calc/
 */


#include "cmath.h"
#include "byteswap.h"


#include "attribute.h"
#include "banned.h"	/* include after system header <> includes */


/*
 * swap_b8_in_HALFs - swap 8 and if needed, 16 bits in an array of HALFs
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a HALF array to swap
 *	len	- length of the src HALF array in HALFs
 *
 * returns:
 *	pointer to where the swapped src has been put
 */
HALF *
swap_b8_in_HALFs(HALF *dest, HALF *src, LEN len)
{
	HALF *ret;
	LEN i;

	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {
		dest = alloc(len);
	}
	ret = dest;

	/*
	 * swap the array
	 */
	for (i=0; i < len; ++i, ++dest, ++src) {
		SWAP_B8_IN_HALF(dest, src);
	}

	/*
	 * return the result
	 */
	return ret;
}


/*
 * swap_b8_in_ZVALUE - swap 8 and if needed, 16 bits in a ZVALUE
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a ZVALUE to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a ZVALUE.
 */
ZVALUE *
swap_b8_in_ZVALUE(ZVALUE *dest, ZVALUE *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(ZVALUE));
		if (dest == NULL) {
			math_error("swap_b8_in_ZVALUE: swap_b8_in_ZVALUE: "
				    "Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_b8_in_ZVALUE) and swap storage
		 */
		dest->v = swap_b8_in_HALFs(NULL, src->v, src->len);

	} else {

		/*
		 * swap storage
		 */
		if (dest->v != NULL) {
			zfree(*dest);
		}
		dest->v = swap_b8_in_HALFs(NULL, src->v, src->len);
	}

	/*
	 * swap or copy the rest of the ZVALUE elements
	 */
	if (all) {
		SWAP_B8_IN_LEN(&dest->len, &src->len);
		SWAP_B8_IN_BOOL(&dest->sign, &src->sign);
	} else {
		dest->len = src->len;
		dest->sign = src->sign;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_b8_in_NUMBER - swap 8 and if needed, 16 bits in a NUMBER
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a NUMBER to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a NUMBER.
 */
NUMBER *
swap_b8_in_NUMBER(NUMBER *dest, NUMBER *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(NUMBER));
		if (dest == NULL) {
			math_error("swap_b8_in_NUMBER: Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_b8_in_ZVALUE) and swap storage
		 */
		dest->num = *swap_b8_in_ZVALUE(NULL, &src->num, all);
		dest->den = *swap_b8_in_ZVALUE(NULL, &src->den, all);

	} else {

		/*
		 * swap storage
		 */
		dest->num = *swap_b8_in_ZVALUE(&dest->num, &src->num, all);
		dest->den = *swap_b8_in_ZVALUE(&dest->den, &src->den, all);
	}

	/*
	 * swap or copy the rest of the NUMBER elements
	 */
	if (all) {
		SWAP_B8_IN_LONG(&dest->links, &src->links);
	} else {
		dest->links = src->links;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_b8_in_COMPLEX - swap 8 and if needed, 16 bits in a COMPLEX
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a COMPLEX to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a COMPLEX.
 */
COMPLEX *
swap_b8_in_COMPLEX(COMPLEX *dest, COMPLEX *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(COMPLEX));
		if (dest == NULL) {
			math_error("swap_b8_in_COMPLEX: Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_b8_in_ZVALUE) and swap storage
		 */
		dest->real = swap_b8_in_NUMBER(NULL, src->real, all);
		dest->imag = swap_b8_in_NUMBER(NULL, src->imag, all);

	} else {

		/*
		 * swap storage
		 */
		dest->real = swap_b8_in_NUMBER(dest->real, src->real, all);
		dest->imag = swap_b8_in_NUMBER(dest->imag, src->imag, all);
	}

	/*
	 * swap or copy the rest of the NUMBER elements
	 */
	if (all) {
		SWAP_B8_IN_LONG(&dest->links, &src->links);
	} else {
		dest->links = src->links;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_b16_in_HALFs - swap 16 bits in an array of HALFs
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a HALF array to swap
 *	len	- length of the src HALF array in HALFs
 *
 * returns:
 *	pointer to where the swapped src has been put
 */
HALF *
swap_b16_in_HALFs(HALF *dest, HALF *src, LEN len)
{
	HALF *ret;
	LEN i;

	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {
		dest = alloc(len);
	}
	ret = dest;

	/*
	 * swap the array
	 */
	for (i=0; i < len; ++i, ++dest, ++src) {
		SWAP_B16_IN_HALF(dest, src);
	}

	/*
	 * return the result
	 */
	return ret;
}


/*
 * swap_HALFs - swap HALFs in an array of HALFs
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a HALF array to swap
 *	len	- length of the src HALF array in HALFs
 *
 * returns:
 *	pointer to where the swapped src has been put
 */
HALF *
swap_HALFs(HALF *dest, HALF *src, LEN len)
{
	HALF *s;	/* src swap pointer */
	HALF *d;	/* dest swap pointer */
	HALF *ret;
	LEN i;

	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {
		dest = alloc(len);
	}
	ret = dest;

	/*
	 * swap HALFs in the array
	 */
	s = src;
	d = &dest[len-1];
	for (i=0; i < len; ++i, --d, ++s) {
		*d = *s;
	}

	/*
	 * return the result
	 */
	return ret;
}


/*
 * swap_b16_in_ZVALUE - swap 16 bits in a ZVALUE
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a ZVALUE to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a ZVALUE.
 */
ZVALUE *
swap_b16_in_ZVALUE(ZVALUE *dest, ZVALUE *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(ZVALUE));
		if (dest == NULL) {
			math_error("swap_b16_in_ZVALUE: Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_b16_in_ZVALUE) and swap storage
		 */
		dest->v = swap_b16_in_HALFs(NULL, src->v, src->len);

	} else {

		/*
		 * swap storage
		 */
		if (dest->v != NULL) {
			zfree(*dest);
		}
		dest->v = swap_b16_in_HALFs(NULL, src->v, src->len);
	}

	/*
	 * swap or copy the rest of the ZVALUE elements
	 */
	if (all) {
		SWAP_B16_IN_LEN(&dest->len, &src->len);
		SWAP_B16_IN_BOOL(&dest->sign, &src->sign);
	} else {
		dest->len = src->len;
		dest->sign = src->sign;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_b16_in_NUMBER - swap 16 bits in a NUMBER
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a NUMBER to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a NUMBER.
 */
NUMBER *
swap_b16_in_NUMBER(NUMBER *dest, NUMBER *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(NUMBER));
		if (dest == NULL) {
			math_error("swap_b16_in_NUMBER: Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_b16_in_ZVALUE) and swap storage
		 */
		dest->num = *swap_b16_in_ZVALUE(NULL, &src->num, all);
		dest->den = *swap_b16_in_ZVALUE(NULL, &src->den, all);

	} else {

		/*
		 * swap storage
		 */
		dest->num = *swap_b16_in_ZVALUE(&dest->num, &src->num, all);
		dest->den = *swap_b16_in_ZVALUE(&dest->den, &src->den, all);
	}

	/*
	 * swap or copy the rest of the NUMBER elements
	 */
	if (all) {
		SWAP_B16_IN_LONG(&dest->links, &src->links);
	} else {
		dest->links = src->links;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_b16_in_COMPLEX - swap 16 bits in a COMPLEX
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a COMPLEX to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a COMPLEX.
 */
COMPLEX *
swap_b16_in_COMPLEX(COMPLEX *dest, COMPLEX *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(COMPLEX));
		if (dest == NULL) {
			math_error("swap_b16_in_COMPLEX: Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_b16_in_ZVALUE) and swap storage
		 */
		dest->real = swap_b16_in_NUMBER(NULL, src->real, all);
		dest->imag = swap_b16_in_NUMBER(NULL, src->imag, all);

	} else {

		/*
		 * swap storage
		 */
		dest->real = swap_b16_in_NUMBER(dest->real, src->real, all);
		dest->imag = swap_b16_in_NUMBER(dest->imag, src->imag, all);
	}

	/*
	 * swap or copy the rest of the NUMBER elements
	 */
	if (all) {
		SWAP_B16_IN_LONG(&dest->links, &src->links);
	} else {
		dest->links = src->links;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_HALF_in_ZVALUE - swap HALFs in a ZVALUE
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a ZVALUE to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a ZVALUE.
 */
ZVALUE *
swap_HALF_in_ZVALUE(ZVALUE *dest, ZVALUE *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(ZVALUE));
		if (dest == NULL) {
			math_error("swap_HALF_in_ZVALUE: Not enough memory");
			not_reached();
		}

		/*
		 * copy storage because we are dealing with HALFs
		 */
		dest->v = (HALF *) zcopyval(*src, *dest);

	} else {

		/*
		 * copy storage because we are dealing with HALFs
		 */
		if (dest->v != NULL) {
			zfree(*dest);
			dest->v = alloc(src->len);
		}
		zcopyval(*src, *dest);
	}

	/*
	 * swap or copy the rest of the ZVALUE elements
	 */
	if (all) {
		SWAP_HALF_IN_LEN(&dest->len, &src->len);
		SWAP_HALF_IN_BOOL(&dest->sign, &src->sign);
	} else {
		dest->len = src->len;
		dest->sign = src->sign;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_HALF_in_NUMBER - swap HALFs in a NUMBER
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a NUMBER to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a NUMBER.
 */
NUMBER *
swap_HALF_in_NUMBER(NUMBER *dest, NUMBER *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(NUMBER));
		if (dest == NULL) {
			math_error("swap_HALF_in_NUMBER: Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_HALF_in_ZVALUE) and swap storage
		 */
		dest->num = *swap_HALF_in_ZVALUE(NULL, &src->num, all);
		dest->den = *swap_HALF_in_ZVALUE(NULL, &src->den, all);

	} else {

		/*
		 * swap storage
		 */
		dest->num = *swap_HALF_in_ZVALUE(&dest->num, &src->num, all);
		dest->den = *swap_HALF_in_ZVALUE(&dest->den, &src->den, all);
	}

	/*
	 * swap or copy the rest of the NUMBER elements
	 */
	if (all) {
		SWAP_HALF_IN_LONG(&dest->links, &src->links);
	} else {
		dest->links = src->links;
	}

	/*
	 * return the result
	 */
	return dest;
}


/*
 * swap_HALF_in_COMPLEX - swap HALFs in a COMPLEX
 *
 * given:
 *	dest	- pointer to where the swapped src will be put or
 *		  NULL to allocate the storage
 *	src	- pointer to a COMPLEX to swap
 *	all	- TRUE => swap every element, FALSE => swap only the
 *		  multi-precision storage
 *
 * returns:
 *	pointer to where the swapped src has been put
 *
 * This macro will either switch to the opposite byte sex (Big Endian vs.
 * Little Endian) the elements of a COMPLEX.
 */
COMPLEX *
swap_HALF_in_COMPLEX(COMPLEX *dest, COMPLEX *src, BOOL all)
{
	/*
	 * allocate storage if needed
	 */
	if (dest == NULL) {

		/*
		 * allocate the storage
		 */
		dest = malloc(sizeof(COMPLEX));
		if (dest == NULL) {
			math_error("swap_HALF_in_COMPLEX: Not enough memory");
			not_reached();
		}

		/*
		 * allocate (by forcing swap_HALF_in_ZVALUE) and swap storage
		 */
		dest->real = swap_HALF_in_NUMBER(NULL, src->real, all);
		dest->imag = swap_HALF_in_NUMBER(NULL, src->imag, all);

	} else {

		/*
		 * swap storage
		 */
		dest->real = swap_HALF_in_NUMBER(dest->real, src->real, all);
		dest->imag = swap_HALF_in_NUMBER(dest->imag, src->imag, all);
	}

	/*
	 * swap or copy the rest of the NUMBER elements
	 */
	if (all) {
		SWAP_HALF_IN_LONG(&dest->links, &src->links);
	} else {
		dest->links = src->links;
	}

	/*
	 * return the result
	 */
	return dest;
}
