atom.h

/*  Part of SWI-Prolog

    Author:        Jan Wielemaker
    E-mail:        J.Wielemaker@cs.vu.nl
    WWW:           http://www.swi-prolog.org
    Copyright (C): 2002-2010, University of Amsterdam
			      VU University Amsterdam

    This 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
*/

#ifndef ATOM_H_INCLUDED
#define ATOM_H_INCLUDED
#include <SWI-Stream.h>
#include <SWI-Prolog.h>
#include <wchar.h>

#define MAX_LIKE_CHOICES	100	/* max *'s in like pattern */

#define STR_MATCH_CASE		0x0	/* Default: perfect match */
#define STR_MATCH_PLAIN		0x1	/* Same, also match qualifier */
#define	STR_MATCH_EXACT		0x2	/* case-insensitive */
					/* keep after exact */
#define	STR_MATCH_SUBSTRING	0x3	/* substring */
#define	STR_MATCH_WORD		0x4	/* whole word */
#define	STR_MATCH_PREFIX	0x5	/* prefix */
#define STR_MATCH_LIKE		0x6	/* SeRQL *like* match */
					/* Keep after LIKE */
#define STR_MATCH_LE		0x7	/* =< */
#define STR_MATCH_GE		0x8	/* >= */
#define STR_MATCH_BETWEEN	0x9	/* X .. Y */
					/* MAX: 0xf (4 bits in triple) */

typedef unsigned char charA;
typedef wchar_t       charW;

typedef struct text
{ const charA *a;
  const charW *w;
  size_t length;
} text;


typedef struct atom_info
{ atom_t	handle;
  text		text;
  int		resolved;
  int		rc;			/* TRUE if text atom */
} atom_info;


#ifdef COMPACT
typedef unsigned int atom_id;
#define ATOM_ID_SHIFT	7		/* Sync with SWI-Prolog */
#define TAG_ATOM	0x00000004L

#define ATOM_ID(a)	((atom_id)(((uintptr_t)(a))>>ATOM_ID_SHIFT))
#define ID_ATOM(id)	(((uintptr_t)(id)<<ATOM_ID_SHIFT)|TAG_ATOM)
#else
typedef atom_t	atom_id;
#define ATOM_ID(a)	(a)
#define ID_ATOM(id)	(id)
#endif

int	cmp_atoms(atom_t a1, atom_t a2);
int	cmp_atom_info(atom_info *a1, atom_t a2);
atom_t	first_atom(atom_t a, int match);
int	match_atoms(int how, atom_t search, atom_t label);
unsigned int atom_hash_case(atom_t a);
int	atom_lang_matches(atom_t lang, atom_t pattern);

#endif /*ATOM_H_INCLUDED*/