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/* $OpenBSD: cpy.y,v 1.2 2007/10/12 07:22:44 otto Exp $ */
/*
* Copyright (c) 2004 Anders Magnusson (ragge@ludd.luth.se).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright(C) Caldera International Inc. 2001-2002. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code and documentation must retain the above
* copyright notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed or owned by Caldera
* International, Inc.
* Neither the name of Caldera International, Inc. nor the names of other
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
* INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE
* FOR ANY DIRECT, INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OFLIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
%{
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "cpp.h"
void yyerror(char *);
int yylex(void);
struct val eval(struct nd *);
%}
%term stop
%term EQ NE LE GE LS RS
%term ANDAND OROR IDENT NUMBER
/*
* The following terminals are not used in the yacc code.
*/
%term STRING FPOINT WSPACE VA_ARGS CONCAT MKSTR ELLIPS
%left ','
%right '='
%right '?' ':'
%left OROR
%left ANDAND
%left '|' '^'
%left '&'
%binary EQ NE
%binary '<' '>' LE GE
%left LS RS
%left '+' '-'
%left '*' '/' '%'
%right '!' '~' UMINUS
%left '(' '.'
%union {
struct val val;
struct nd *node;
}
%type <val> NUMBER
%type <node> term e
%%
S: e '\n' { return(eval($1).v.val != 0);}
e: e '*' e
{$$ = mknode('*', $1, $3);}
| e '/' e
{$$ = mknode('/', $1, $3);}
| e '%' e
{$$ = mknode('%', $1, $3);}
| e '+' e
{$$ = mknode('+', $1, $3);}
| e '-' e
{$$ = mknode('-', $1, $3);}
| e LS e
{$$ = mknode(LS, $1, $3);}
| e RS e
{$$ = mknode(RS, $1, $3);}
| e '<' e
{$$ = mknode('<', $1, $3);}
| e '>' e
{$$ = mknode('>', $1, $3);}
| e LE e
{$$ = mknode(LE, $1, $3);}
| e GE e
{$$ = mknode(GE, $1, $3);}
| e EQ e
{$$ = mknode(EQ, $1, $3);}
| e NE e
{$$ = mknode(NE, $1, $3);}
| e '&' e
{$$ = mknode('&', $1, $3);}
| e '^' e
{$$ = mknode('^', $1, $3);}
| e '|' e
{$$ = mknode('|', $1, $3);}
| e ANDAND e
{$$ = mknode(ANDAND, $1, $3);}
| e OROR e
{$$ = mknode(OROR, $1, $3);}
| e '?' e ':' e {
struct nd *n = mknode(':', $3, $5);
$$ = mknode('?', $1, n);}
| e ',' e
{$$ = mknode(',', $1, $3);}
| term
{$$ = $1;}
term:
'-' term %prec UMINUS
{$$ = mknode(UMINUS, $2, NULL);}
| '+' term %prec UMINUS
{$$ = $2;}
| '!' term
{$$ = mknode('!', $2, NULL);}
| '~' term
{$$ = mknode('~', $2, NULL);}
| '(' e ')'
{$$ = $2;}
| NUMBER
{$$= mknum($1);}
%%
void
yyerror(char *err)
{
error(err);
}
struct nd *
mknode(int op, struct nd *left, struct nd *right)
{
struct nd *r = malloc(sizeof(*r));
if (r == NULL)
error("out of mem");
r->op = op;
r->nd_left = left;
r->nd_right = right;
return r;
}
struct nd *
mknum(struct val val)
{
struct nd *r = malloc(sizeof(*r));
if (r == NULL)
error("out of mem");
r->op = NUMBER;
r->n.v = val;
return r;
}
#define EVALUNARY(tok, op, t, x) \
case (tok): if (t) ret.v.uval = op x.v.uval; \
else ret.v.val = op x.v.val; \
ret.type = t; \
break;
#define EVALBIN(tok, op, t, x, y, r) \
case (tok): if (t) ret.v.uval = x.v.uval op y.v.uval; \
else ret.v.val = x.v.val op y.v.val; \
ret.type = r; \
break;
struct val
eval(struct nd *tree)
{
struct val ret, l, r;
int t;
switch (tree->op) {
case NUMBER:
ret.type = tree->nd_type;
if (ret.type)
ret.v.uval = tree->nd_uval;
else
ret.v.val = tree->nd_val;
goto out;
case LS:
case RS:
r = eval(tree->nd_right);
/* FALLTHROUGH */
case UMINUS:
case '~':
case '!':
l = eval(tree->nd_left);
switch (tree->op) {
EVALBIN(LS, <<, l.type, l, r, l.type);
EVALBIN(RS, >>, l.type, l, r, l.type);
EVALUNARY(UMINUS, -, l.type, l);
EVALUNARY('~', ~, l.type, l);
EVALUNARY('!', !, 0, l);
}
goto out;
case '?':
l = eval(tree->nd_left);
// XXX mem leak
if (l.v.val)
ret = eval(tree->nd_right->nd_left);
else
ret = eval(tree->nd_right->nd_right);
goto out;
case OROR:
l = eval(tree->nd_left);
// XXX mem leak
if (l.v.val)
ret = l;
else
ret = eval(tree->nd_right);
ret.type = 0;
goto out;
case ANDAND:
l = eval(tree->nd_left);
// XXX mem leak
if (l.v.val)
ret = eval(tree->nd_right);
else
ret = l;
ret.type = 0;
goto out;
case ',':
// XXX mem leak
ret = eval(tree->nd_right);
goto out;
}
l = eval(tree->nd_left);
r = eval(tree->nd_right);
t = l.type || r.type;
switch (tree->op) {
EVALBIN(EQ, ==, t, l, r, 0);
EVALBIN(NE, !=, t, l, r, 0);
EVALBIN('<', <, t, l, r, 0);
EVALBIN('>', >, t, l, r, 0);
EVALBIN(GE, >=, t, l, r, 0);
EVALBIN(LE, <=, t, l, r, 0);
EVALBIN('+', +, t, l, r, t);
EVALBIN('-', -, t, l, r, t);
EVALBIN('*', *, t, l, r, t);
// XXX check /,% by zero
EVALBIN('/', /, t, l, r, t);
EVALBIN('%', %, t, l, r, t);
EVALBIN('&', &, t, l, r, t);
EVALBIN('|', |, t, l, r, t);
EVALBIN('^', ^, t, l, r, t);
}
out:
free(tree);
return ret;
}
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