Subversion Repositories filter_foundry

%{

/*

	This file is part of "Filter Foundry", a filter plugin for Adobe Photoshop

    Copyright (C) 2003-5 Toby Thain, toby@telegraphics.com.au

    This program is free software; you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by  

    the Free Software Foundation; either version 2 of the License, or

    (at your option) any later version.

    This program 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 General Public License for more details.

    You should have received a copy of the GNU General Public License  

    along with this program; if not, write to the Free Software

    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

*/

#include <stdio.h>

#include <string.h>

#ifndef false

#define false 0

#define true 1

#endif

#include "node.h"

#include "y.tab.h"

//#ifdef MAC_ENV

int yyparse(void);

int yylex(void); // hack. correct prototype is buried in lex output

//#endif

void yyerror(char*);

int pushflag(int x);

struct node *parseexpr(char *s);

#define DPARSE 

struct node *parsetree;

char *errstr;

enum{ PARENSTACK = 100 };

int inarglist[PARENSTACK],arglistptr; // keep track of whether a comma is an function argument separator, or operator

int pushflag(int x){

	if(arglistptr < (PARENSTACK-1))

		inarglist[++arglistptr] = x;

	else{

		yyerror("too many nested parentheses or function calls");

		return true;

	}

	return false;

}

#define POP() --arglistptr

#define ENTERARGS() if(pushflag(true)) YYERROR

#define ENTERPAREN() if(pushflag(false)) YYERROR

#define LEAVEARGS POP

#define LEAVEPAREN POP

%}

%token TOK_NUM TOK_EOF TOK_ARGSEP

%token TOK_FN1 TOK_FN2 TOK_FN3 TOK_FN4 TOK_FN5 TOK_FN10

%token TOK_SPECIALVAR TOK_VAR TOK_UNKNOWN TOK_BADCHAR

%left ','

%left '?' ':'

%left LOGAND LOGOR

%left '&' '^' '|'

%left EQ NE

%left '<' LE '>' GE

%left SHLEFT SHRIGHT

%left '-' '+'

%left '*' '/' '%'

%right EXP

%left NEG 

%%

input : expr { parsetree = $1; } ;

expr : TOK_NUM 

	| TOK_VAR

	| TOK_SPECIALVAR

	| TOK_FN1 '(' {ENTERARGS();} expr ')' {LEAVEARGS();}

		{ $$ = $1; $$->child[0] = $4; }

	| TOK_FN2 '(' {ENTERARGS();} expr TOK_ARGSEP expr ')' {LEAVEARGS();}

		{ $$ = $1; $$->child[0] = $4; $$->child[1] = $6; }

	| TOK_FN3 '(' {ENTERARGS();} expr TOK_ARGSEP expr TOK_ARGSEP expr ')' {LEAVEARGS();}

		{ $$ = $1; $$->child[0] = $4; $$->child[1] = $6; $$->child[2] = $8; }

	| TOK_FN4 '(' {ENTERARGS();} expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP expr ')' {LEAVEARGS();}

		{ $$ = $1; $$->child[0] = $4; $$->child[1] = $6; $$->child[2] = $8; $$->child[3] = $10; }

	| TOK_FN5 '(' {ENTERARGS();} expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP expr ')' {LEAVEARGS();}

		{ $$ = $1; $$->child[0] = $4; $$->child[1] = $6; $$->child[2] = $8; $$->child[3] = $10; $$->child[4] = $12; }

	| TOK_FN10 '(' {ENTERARGS();} 

			expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP

			expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP expr TOK_ARGSEP expr

			')' {LEAVEARGS();}

		{ $$ = $1; 

			$$->child[0] = $4;  $$->child[1] = $6;  $$->child[2] = $8;  $$->child[3] = $10; $$->child[4] = $12;

			$$->child[5] = $14; $$->child[6] = $16; $$->child[7] = $18; $$->child[8] = $20; $$->child[9] = $22; 

		}

	| '(' {ENTERPAREN();} expr ')' { LEAVEPAREN(); $$ = $3; }

/* arithmetic operators */

	| expr '+' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '-' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '*' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '/' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '%' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

/* exponentiation (not in FF spec) */

	| expr EXP expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

/* relational operators */

	| expr EQ expr  { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr NE expr  { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '<' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr LE expr  { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '>' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr GE expr  { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

/* logical operators */

	| expr LOGAND expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr LOGOR expr  { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| '!' expr %prec NEG { $$ = $1; $$->child[0] = $2; }

/* conditional operator */

	| expr '?' expr ':' expr

		{ $$ = $2; $$->child[0] = $1; $$->child[1] = $3; $$->child[2] = $5; }

/* bitwise operators */

	| expr '&' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '^' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr '|' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr SHLEFT expr  { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| expr SHRIGHT expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

	| '~' expr %prec NEG { $$ = $1; $$->child[0] = $2; }

/* sequence operator */

	| expr ',' expr { $$ = $2; $$->child[0] = $1; $$->child[1] = $3; }

/* unary operators */

	| '-' expr %prec NEG { $$ = $1; $$->child[0] = 0; $$->child[1] = $2; }

	| '+' expr %prec NEG { $$ = $2; }

/* error tokens */

	| TOK_UNKNOWN { yyerror("unknown name"); YYERROR; }

	| TOK_BADCHAR { yyerror("disallowed character"); YYERROR; }

	;

%%

struct node *parseexpr(char *s){

	void *yy_scan_string(const char*); // hack. correct prototype is buried in lex output

	int yyparse(void); // hack. correct prototype appears just after this code, in yacc output

	extern int tokpos,tokstart;

	tokstart = tokpos = 0;

	if(s){

		arglistptr = 0;

		inarglist[arglistptr] = false;

		node_list = 0;

		yy_scan_string(s);

		if(!yyparse())

			return parsetree;

		else /* ensure we don't leak memory, on an unsuccessful parse */

			freeallnodes();

	}else

		yyerror("null string???");

	return 0;

}

void yyerror(char *msg){

	errstr = msg;

}