[catacomb] / math / mpint.h

/* -*-c-*-
 *
 * Conversion between MPs and standard C integers
 *
 * (c) 1999 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of Catacomb.
 *
 * Catacomb is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * Catacomb 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 Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with Catacomb; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

#ifndef CATACOMB_MPINT_H
#define CATACOMB_MPINT_H

#ifdef __cplusplus
  extern "C" {
#endif

/*----- Header files ------------------------------------------------------*/

#include <limits.h>

#include <mLib/macros.h>

#ifndef CATACOMB_MP_H
#  include "mp.h"
#endif

/*----- Generic translation macros ----------------------------------------*/

/* --- Warning damage control --- *
 *
 * GCC (at least) isn't clever enough to work out that the division in
 * @MP_FROMINT@ is actually safe (since it will only be executed if @_i >
 * MPW_MAX@, which would prove that @(type)MPW_MAX + 1 != 0@).
 */

/* --- @MP_FROMINT@ --- *
 *
 * Arguments:	@d@ = destination multiprecision integer
 *		@type@ = type of integer which @i@ is
 *		@i@ = a standard C integer
 *
 * Use:		Stores the value of @i@ in @d@.  This macro is actually
 *		rather subtle in places.  Be careful what you change.
 */

#define MP_FROMINT(d, type, i) do {					\
  type _i = (i);							\
  size_t _o = 0;							\
  mp *_d = (d);								\
  size_t _sz = 4;							\
									\
  MP_DEST(_d, _sz, 0);							\
  _d->f &= ~(MP_NEG | MP_UNDEF);					\
									\
  if (_i >= 0) {							\
    while (_i) {							\
      if (_o == _sz) {							\
	_sz <<= 1;							\
	MP_ENSURE(_d, _sz);						\
      }									\
      _d->v[_o++] = MPW(_i);						\
      if (_i <= MPW_MAX)						\
	break;								\
      else								\
	MUFFLE_WARNINGS_STMT(GCC_WARNING("-Wdiv-by-zero"), {		\
	  _i /= (type)MPW_MAX + 1;					\
	});								\
    }									\
  } else {								\
    _d->f |= MP_NEG;							\
    while (_i) {							\
      if (_o == _sz) {							\
	_sz <<= 1;							\
	MP_ENSURE(_d, _sz);						\
      }									\
      _d->v[_o++] = MPW(-_i);						\
      if (_i >= -MPW_MAX)						\
	break;								\
      else								\
	MUFFLE_WARNINGS_STMT(GCC_WARNING("-Wdiv-by-zero"), {		\
	  _i /= (type)MPW_MAX + 1;					\
	});								\
    }									\
  }									\
									\
  _d->vl = _d->v + _o;							\
  (d) = _d;								\
} while (0)

/* --- @MP_TOINT@ --- *
 *
 * Arguments:	@m@ = a multiprecision integer
 *		@type@ = the type of @i@
 *		@max@ = the largest value @i@ can represent
 *		@i@ = an integer variable
 *
 * Use:		Stores the value of a multiprecision integer in a standard C
 *		integer.  If the value won't fit, the behaviour is determined
 *		by the type of @i@: if @i@ is unsigned, the value of the
 *		multiprecision integer modulo @max + 1@ is stored; if @i@ is
 *		signed, the behaviour is undefined.
 *
 *		If you don't want to be bitten by these sorts of things, keep
 *		copies of @INT_MAX@ or whatever is appropriate in
 *		multiprecision form and compare before conversion.
 */

#define MP_TOINT(m, type, max, i) do {					\
  type _i = 0;								\
  type _max = (max);							\
  unsigned _s = 0;							\
  const mp *_m = (m);							\
  const mpw *_v = _m->v, *_vl = _m->vl;					\
									\
  /* --- Do all the arithmetic in negative numbers --- */		\
									\
  while (_v < _vl && _max > 0) {					\
    _i -= (type)*_v << _s;						\
    _s += MPW_BITS;							\
    _v++;								\
    _max /= (mpd)MPW_MAX + 1;						\
  }									\
  if (!MP_NEGP(_m))							\
    _i = -_i;								\
  (i) = _i;								\
} while (0)

/*----- Functions provided ------------------------------------------------*/

/* --- Build up the list of conversions to be supplied --- */

#ifdef ULLONG_MAX
#  ifndef LLONG_MAX
#    define LLONG_MAX LONG_LONG_MAX
#  endif
#  define MPINT_CONV_LLONG(_)						\
  _(llong, long long, LLONG_MAX)					\
  _(ullong, unsigned long long, ULLONG_MAX)
#else
#  define MPINT_CONV_LLONG(_)
#endif

#ifdef INTMAX_MAX
#  define MPINT_CONV_INTMAX(_)						\
  _(intmax, intmax_t, INTMAX_MAX)					\
  _(uintmax, uintmax_t, UINTMAX_MAX)
#else
#  define MPINT_CONV_INTMAX(_)
#endif

#ifdef HAVE_UINT64
#  define MPINT_CONV_U64(_) _(uint64, uint64, MASK64)
#else
#  define MPINT_CONV_U64(_)
#endif

#define MPINT_CONVERSIONS(_)						\
  _(short, short, SHRT_MAX)						\
  _(ushort, unsigned short, USHRT_MAX)					\
  _(int, int, INT_MAX)							\
  _(uint, unsigned, UINT_MAX)						\
  _(long, long, LONG_MAX)						\
  _(ulong, unsigned long, ULONG_MAX)					\
  MPINT_CONV_LLONG(_)							\
  _(uint8, uint8, MASK8)						\
  _(uint16, uint16, MASK16)						\
  _(uint24, uint24, MASK24)						\
  _(uint32, uint32, MASK32)						\
  MPINT_CONV_U64(_)							\
  MPINT_CONV_INTMAX(_)							\
  _(sizet, size_t, (size_t)-1)

/* --- @mp_fromINT@ --- *
 *
 * Arguments:	@mp *d@ = pointer to destination multiprecision integer
 *		@INT i@ = standard C integer to convert
 *
 * Returns:	The resulting multiprecision integer.
 *
 * Use:		Converts a standard C integer to a multiprecision integer.
 */

#define mp_fromINT(name, type, max)					\
  extern mp *mp_from##name(mp */*d*/, type /*i*/);
MPINT_CONVERSIONS(mp_fromINT)
#undef mp_fromINT

/* --- @mp_toINT@ --- *
 *
 * Arguments:	@const mp *m@ = pointer to a multiprecision integer
 *
 * Returns:	The value of the integer @m@ as a C integer.
 *
 * Use:		Converts a multiprecision integer to a standard C integer.
 *		If the value of the multiprecision integer cannot be
 *		represented in the return type, and the return type is
 *		unsigned, it is reduced modulo @TYPE_MAX + 1@; if the return
 *		type is signed, the behaviour is undefined.
 */

#define mp_toINT(name, type, max)					\
  extern type mp_to##name(const mp */*m*/);
MPINT_CONVERSIONS(mp_toINT)
#undef mp_toINT

/*----- That's all, folks -------------------------------------------------*/

#ifdef __cplusplus
  }
#endif

#endif
Commit	Line	Data
70b904c5	1	/* --c--
70b904c5	2	*
70b904c5	3	* Conversion between MPs and standard C integers
	4	*
	5	* (c) 1999 Straylight/Edgeware
	6	*/
	7
45c0fd36	8	/----- Licensing notice --------------------------------------------------
70b904c5	9	*
	10	* This file is part of Catacomb.
	11	*
	12	* Catacomb is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU Library General Public License as
	14	* published by the Free Software Foundation; either version 2 of the
	15	* License, or (at your option) any later version.
45c0fd36	16	*
70b904c5	17	* Catacomb is distributed in the hope that it will be useful,
	18	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	* GNU Library General Public License for more details.
45c0fd36	21	*
70b904c5	22	* You should have received a copy of the GNU Library General Public
	23	* License along with Catacomb; if not, write to the Free
	24	* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
	25	* MA 02111-1307, USA.
	26	*/
	27
92c2a290	28	#ifndef CATACOMB_MPINT_H
92c2a290	29	#define CATACOMB_MPINT_H
70b904c5	30
	31	#ifdef __cplusplus
	32	extern "C" {
	33	#endif
	34
	35	/----- Header files ------------------------------------------------------/
	36
	37	#include <limits.h>
	38
23bbea75 MW	39	#include <mLib/macros.h>
23bbea75 MW	40
92c2a290	41	#ifndef CATACOMB_MP_H
70b904c5	42	# include "mp.h"
	43	#endif
	44
	45	/----- Generic translation macros ----------------------------------------/
	46
aa02ed36 MW	47	/* --- Warning damage control --- *
	48	*
	49	* GCC (at least) isn't clever enough to work out that the division in
	50	* @MP_FROMINT@ is actually safe (since it will only be executed if @_i >
23bbea75	51	* MPW_MAX@, which would prove that @(type)MPW_MAX + 1 != 0@).
aa02ed36 MW	52	*/
aa02ed36 MW	53
70b904c5	54	/* --- @MP_FROMINT@ --- *
	55	*
	56	* Arguments: @d@ = destination multiprecision integer
	57	* @type@ = type of integer which @i@ is
	58	* @i@ = a standard C integer
	59	*
	60	* Use: Stores the value of @i@ in @d@. This macro is actually
	61	* rather subtle in places. Be careful what you change.
	62	*/
	63
	64	#define MP_FROMINT(d, type, i) do { \
	65	type _i = (i); \
	66	size_t _o = 0; \
	67	mp *_d = (d); \
	68	size_t _sz = 4; \
	69	\
d34decd2	70	MP_DEST(_d, _sz, 0); \
70b904c5	71	_d->f &= ~(MP_NEG \| MP_UNDEF); \
70b904c5	72	\
3485fc41 MW	73	if (_i >= 0) { \
	74	while (_i) { \
	75	if (_o == _sz) { \
	76	_sz <<= 1; \
	77	MP_ENSURE(_d, _sz); \
	78	} \
	79	_d->v[_o++] = MPW(_i); \
7eaaecf5	80	if (_i <= MPW_MAX) \
3485fc41 MW	81	break; \
3485fc41 MW	82	else \
23bbea75 MW	83	MUFFLE_WARNINGS_STMT(GCC_WARNING("-Wdiv-by-zero"), { \
	84	_i /= (type)MPW_MAX + 1; \
	85	}); \
3485fc41 MW	86	} \
3485fc41 MW	87	} else { \
70b904c5	88	_d->f \|= MP_NEG; \
3485fc41 MW	89	while (_i) { \
	90	if (_o == _sz) { \
	91	_sz <<= 1; \
	92	MP_ENSURE(_d, _sz); \
	93	} \
	94	_d->v[_o++] = MPW(-_i); \
7eaaecf5	95	if (_i >= -MPW_MAX) \
3485fc41 MW	96	break; \
3485fc41 MW	97	else \
23bbea75 MW	98	MUFFLE_WARNINGS_STMT(GCC_WARNING("-Wdiv-by-zero"), { \
	99	_i /= (type)MPW_MAX + 1; \
	100	}); \
70b904c5	101	} \
70b904c5	102	} \
3485fc41	103	\
70b904c5	104	_d->vl = _d->v + _o; \
	105	(d) = _d; \
	106	} while (0)
	107
	108	/* --- @MP_TOINT@ --- *
	109	*
	110	* Arguments: @m@ = a multiprecision integer
	111	* @type@ = the type of @i@
	112	* @max@ = the largest value @i@ can represent
	113	* @i@ = an integer variable
	114	*
	115	* Use: Stores the value of a multiprecision integer in a standard C
	116	* integer. If the value won't fit, the behaviour is determined
	117	* by the type of @i@: if @i@ is unsigned, the value of the
	118	* multiprecision integer modulo @max + 1@ is stored; if @i@ is
	119	* signed, the behaviour is undefined.
	120	*
	121	* If you don't want to be bitten by these sorts of things, keep
	122	* copies of @INT_MAX@ or whatever is appropriate in
	123	* multiprecision form and compare before conversion.
	124	*/
	125
	126	#define MP_TOINT(m, type, max, i) do { \
	127	type _i = 0; \
	128	type _max = (max); \
	129	unsigned _s = 0; \
	130	const mp *_m = (m); \
	131	const mpw _v = _m->v, _vl = _m->vl; \
	132	\
	133	/* --- Do all the arithmetic in negative numbers --- */ \
	134	\
	135	while (_v < _vl && _max > 0) { \
c973f431	136	_i -= (type)*_v << _s; \
70b904c5	137	_s += MPW_BITS; \
	138	_v++; \
	139	_max /= (mpd)MPW_MAX + 1; \
	140	} \
a69a3efd	141	if (!MP_NEGP(_m)) \
70b904c5	142	_i = -_i; \
	143	(i) = _i; \
	144	} while (0)
	145
	146	/----- Functions provided ------------------------------------------------/
	147
2302cd86 MW	148	/* --- Build up the list of conversions to be supplied --- */
2302cd86 MW	149
cc08c570 MW	150	#ifdef ULLONG_MAX
	151	# ifndef LLONG_MAX
	152	# define LLONG_MAX LONG_LONG_MAX
	153	# endif
	154	# define MPINT_CONV_LLONG(_) \
	155	_(llong, long long, LLONG_MAX) \
	156	_(ullong, unsigned long long, ULLONG_MAX)
	157	#else
	158	# define MPINT_CONV_LLONG(_)
	159	#endif
	160
	161	#ifdef INTMAX_MAX
	162	# define MPINT_CONV_INTMAX(_) \
	163	_(intmax, intmax_t, INTMAX_MAX) \
	164	_(uintmax, uintmax_t, UINTMAX_MAX)
	165	#else
	166	# define MPINT_CONV_INTMAX(_)
	167	#endif
	168
	169	#ifdef HAVE_UINT64
	170	# define MPINT_CONV_U64(_) _(uint64, uint64, MASK64)
	171	#else
	172	# define MPINT_CONV_U64(_)
	173	#endif
	174
2302cd86 MW	175	#define MPINT_CONVERSIONS(_) \
	176	_(short, short, SHRT_MAX) \
	177	_(ushort, unsigned short, USHRT_MAX) \
	178	_(int, int, INT_MAX) \
	179	_(uint, unsigned, UINT_MAX) \
	180	_(long, long, LONG_MAX) \
	181	_(ulong, unsigned long, ULONG_MAX) \
cc08c570 MW	182	MPINT_CONV_LLONG(_) \
	183	_(uint8, uint8, MASK8) \
	184	_(uint16, uint16, MASK16) \
	185	_(uint24, uint24, MASK24) \
	186	_(uint32, uint32, MASK32) \
	187	MPINT_CONV_U64(_) \
	188	MPINT_CONV_INTMAX(_) \
	189	_(sizet, size_t, (size_t)-1)
2302cd86	190
70b904c5	191	/* --- @mp_fromINT@ --- *
	192	*
	193	* Arguments: @mp *d@ = pointer to destination multiprecision integer
	194	* @INT i@ = standard C integer to convert
	195	*
	196	* Returns: The resulting multiprecision integer.
	197	*
	198	* Use: Converts a standard C integer to a multiprecision integer.
	199	*/
	200
2302cd86 MW	201	#define mp_fromINT(name, type, max) \
	202	extern mp mp_from##name(mp /d/, type /i/);
	203	MPINT_CONVERSIONS(mp_fromINT)
70b904c5	204	#undef mp_fromINT
	205
	206	/* --- @mp_toINT@ --- *
	207	*
	208	* Arguments: @const mp *m@ = pointer to a multiprecision integer
	209	*
	210	* Returns: The value of the integer @m@ as a C integer.
	211	*
	212	* Use: Converts a multiprecision integer to a standard C integer.
	213	* If the value of the multiprecision integer cannot be
	214	* represented in the return type, and the return type is
	215	* unsigned, it is reduced modulo @TYPE_MAX + 1@; if the return
	216	* type is signed, the behaviour is undefined.
	217	*/
	218
2302cd86 MW	219	#define mp_toINT(name, type, max) \
	220	extern type mp_to##name(const mp /m*/);
	221	MPINT_CONVERSIONS(mp_toINT)
70b904c5	222	#undef mp_toINT
	223
	224	/----- That's all, folks -------------------------------------------------/
	225
	226	#ifdef __cplusplus
	227	}
	228	#endif
	229
	230	#endif