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/*
 * $XConsortium: ifparser.h /main/2 1995/08/09 14:10:06 kaleb $
 *
 * Copyright 1992 Network Computing Devices, Inc.
 * 
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose and without fee is hereby granted, provided
 * that the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Network Computing Devices may not be
 * used in advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission.  Network Computing Devices makes
 * no representations about the suitability of this software for any purpose.
 * It is provided ``as is'' without express or implied warranty.
 * 
 * NETWORK COMPUTING DEVICES DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
 * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
 * IN NO EVENT SHALL NETWORK COMPUTING DEVICES BE LIABLE FOR ANY SPECIAL,
 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 * 
 * Author:  Jim Fulton
 *          Network Computing Devices, Inc.
 * 
 * Simple if statement processor
 *
 * This module can be used to evaluate string representations of C language
 * if constructs.  It accepts the following grammar:
 * 
 *     EXPRESSION       :=      VALUE
 *                       |      VALUE  BINOP    EXPRESSION
 * 
 *     VALUE            :=      '('  EXPRESSION  ')'
 *                       |      '!'  VALUE
 *                       |      '-'  VALUE
 *                       |      'defined'  '('  variable  ')'
 *                       |      variable
 *                       |      number
 * 
 *     BINOP            :=      '*'     |  '/'  |  '%'
 *                       |      '+'     |  '-'
 *                       |      '<<'    |  '>>'
 *                       |      '<'     |  '>'  |  '<='  |  '>='
 *                       |      '=='    |  '!='
 *                       |      '&'     |  '|'
 *                       |      '&&'    |  '||'
 * 
 * The normal C order of precidence is supported.
 * 
 * 
 * External Entry Points:
 * 
 *     ParseIfExpression                parse a string for #if
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#define const /**/
typedef int Bool;
#define False 0
#define True 1

typedef struct _if_parser {
    struct {                            /* functions */
        char *(*handle_error) (/* struct _if_parser *, const char *,
                                 const char * */);
        int (*eval_variable) (/* struct _if_parser *, const char *, int */);
        int (*eval_defined) (/* struct _if_parser *, const char *, int */);
    } funcs;
    char *data;
} IfParser;

char *ParseIfExpression (
#ifdef __STDC__
    IfParser *, 
    const char *, 
    long *
#endif
);