82 lines
2.5 KiB
C
82 lines
2.5 KiB
C
/*
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*
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* Copyright 1992 Network Computing Devices, Inc.
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*
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* Permission to use, copy, modify, and distribute this software and its
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* documentation for any purpose and without fee is hereby granted, provided
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* that the above copyright notice appear in all copies and that both that
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* copyright notice and this permission notice appear in supporting
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* documentation, and that the name of Network Computing Devices may not be
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* used in advertising or publicity pertaining to distribution of the software
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* without specific, written prior permission. Network Computing Devices makes
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* no representations about the suitability of this software for any purpose.
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* It is provided ``as is'' without express or implied warranty.
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*
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* NETWORK COMPUTING DEVICES DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
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* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
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* IN NO EVENT SHALL NETWORK COMPUTING DEVICES BE LIABLE FOR ANY SPECIAL,
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* INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
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* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
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* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
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* PERFORMANCE OF THIS SOFTWARE.
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*
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* Author: Jim Fulton
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* Network Computing Devices, Inc.
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*
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* Simple if statement processor
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*
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* This module can be used to evaluate string representations of C language
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* if constructs. It accepts the following grammar:
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*
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* EXPRESSION := VALUE
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* | VALUE BINOP EXPRESSION
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* | VALUE '?' EXPRESSION ':' EXPRESSION
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*
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* VALUE := '(' EXPRESSION ')'
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* | '!' VALUE
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* | '-' VALUE
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* | '~' VALUE
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* | 'defined' '(' variable ')'
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* | variable
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* | number
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*
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* BINOP := '*' | '/' | '%'
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* | '+' | '-'
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* | '<<' | '>>'
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* | '<' | '>' | '<=' | '>='
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* | '==' | '!='
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* | '&' | '^' | '|'
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* | '&&' | '||'
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*
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* The normal C order of precedence is supported.
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*
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*
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* External Entry Points:
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*
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* ParseIfExpression parse a string for #if
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*/
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#include <stdio.h>
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typedef int Bool;
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#define False 0
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#define True 1
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typedef struct _if_parser {
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struct { /* functions */
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const char *(*handle_error) (struct _if_parser *, const char *,
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const char *);
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long (*eval_variable) (struct _if_parser *, const char *, int);
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int (*eval_defined) (struct _if_parser *, const char *, int);
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} funcs;
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char *data;
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} IfParser;
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const char *ParseIfExpression (
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IfParser *,
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const char *,
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long *
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);
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