BrainfuckToC (Flex & Bison)

brainfuck.l

%{
#include "brainfuck.tab.h"
#include <string.h>
#include <stdlib.h>

void error()
{
  fprintf(stdout, "Plik niepoprawny pod wzglêdem leksykalnym. Linia: %d\n", yylineno);
  exit(1);
}

%}

INT     [0-9]+
ID      [A-Za-z][A-Za-z0-9]*

%%
">"		{
		yylval=1;
		return POINTER;
		}

"<"		{
		yylval=-1;
		return POINTER;
		}

"+"		{
		yylval=1;
		return VALUE;
		}

"-"		{
		yylval=-1;
		return VALUE;
		}

"["		{
		return LOOP_BEGIN;
		}

"]"		{
		return LOOP_END;
		}
","		{
		return INPUT;
		}

"."		{
		return OUTPUT;
		}

[ \t] { /* Nic */ }

[\n] { return yytext[0]; } 

. { yylval=yytext[0]; return COMMENT; } 

%%

brainfuck.y

%{
#include <stdio.h>
#include <strings.h>
#define BUF_MAX 3000

int pointerPos=0;

//---------------------------------------
int pointerStack[BUF_MAX];
int stackIndex=-1;

int pointerPush(int pos){
	if(stackIndex>=BUF_MAX)
		return -1; //failor
	stackIndex++;
	pointerStack[stackIndex]=pos;
	return 1; //success
}

int pointerPop(){
	if(stackIndex==-1) return -1; //failor	
	int p = pointerStack[stackIndex];
	stackIndex--;
	return p;
}
//----------------------------------------
int ind=1;

void printInd(){
	int i=0;	
	for(i=0;i<ind;i++){
		printf("\t");	
	}
}
//----------------------------------------

void printHeader(){
	printf("\
#include <stdio.h>\n\
#define BUF_MAX 3000\n\
int buffer[BUF_MAX];\n\n\
main(){\n \
\tint *ptr=&buffer[0];\n"
	);
}

void printFooter(){
	printf("}\n");
}
//----------------------------------------

%}

%token POINTER VALUE INPUT OUTPUT LOOP_BEGIN LOOP_END COMMENT

%%

input: /* nic */
    | input commands
    ;
    

pointer_ch : pointer_ch POINTER { $$ = $1 + $2 } 
           | POINTER
           ;

value_ch : value_ch VALUE { $$ = $1 + $2 } 
	  | VALUE    
          ;

commands : commands pointer_ch { 
				pointerPos=pointerPos+$2; 
				printInd();
				int chVal=$2;
				char sign='+';
				if(chVal!=0){
					if(chVal<0){ 
						sign='-'; 
						chVal*=(-1); 
					}
					if(chVal==1) printf("ptr%c%c;\t\t",sign,sign);
					else printf("ptr%c=%d;\t\t",sign,chVal); 
				}
				printf("//ptr=&buffer[%d]\n",pointerPos); 
				}
	 | commands value_ch { 
				printInd(); 
				int chVal=$2;
				char sign='+';
				if(chVal!=0){
					if(chVal<0){ 
						sign='-'; 
						chVal*=(-1); 
					}
					if(chVal==1) printf("(*ptr)%c%c;\t\t//buffer[%d]%c%c\n",sign, sign, pointerPos,sign,sign);
					else printf("(*ptr)%c=%d;\t\t//buffer[%d]%c=%d\n",sign, chVal,pointerPos,sign,chVal);
				}
			     }
	 | commands INPUT { 
				printInd(); 
				printf("(*ptr)=getchar();"); 
				printf("\t\t//buffer[%d]=getchar();",pointerPos); 
				printf("\n"); 
				}
	 | commands OUTPUT { 
				printInd(); 
				printf("putchar(*ptr);"); 
				printf("\t\t//putchar(buffer[%d]);",pointerPos); 
				printf("\n"); 
				}
	 | commands loop
	 | commands '\n'
         | commands comments { printf("/*comment*/\n"); };
	 | /**/
         ;

		
loop : loop_b commands loop_e
     ;

loop_b : LOOP_BEGIN { 
			putchar('\n'); 
			printInd(); 
			printf("while(*ptr){"); 
			ind++; 
			pointerPush(pointerPos); 
			printf("\t\t//while(buffer[%d]){",pointerPos); 
			printf("\n"); 
			}


loop_e : LOOP_END { 
			ind--; 
			printInd();  
			printf("}"); 
			printf("\t\t//while(buffer[%d]);",pointerPos); 
			int outP=pointerPop(); 
			if(outP==pointerPos) 
				printf("while OK!\n"); 
			else 
				printf("while not OK\n"); 
			printf("\n\n"); }		

comments: comments COMMENT
	| COMMENT
	;
%%

main()
{
  printHeader();
  yyparse();
  printFooter();
}

yyerror(s)
char *s;
{
    fprintf(stderr, "%s\n", s);
}

makefile

#
# Ogolny makefile do specyfikacji dla Flexa i Bisona
#

# Programy do wygenerowania ze specyfikacji dla Yacc'a
YACC = $(patsubst %.y, %, $(wildcard [a-z]*.y))       

# Programy do wygenerowania (tylko) ze specyfikacji dla Lex'a
LEX  = $(filter-out $(YACC), $(patsubst %.l, %, $(wildcard [a-z]*.l)))  

# Wszystkie programy do wygenerowania
EXE  = $(LEX) $(YACC)

# Kody po¶rednie skanerów zale¿nych tylko od specyfikacji skanera
OBJL = $(patsubst %, %.yy.o, $(LEX))

# Kody po¶rednie skanerów zale¿nych od specyfikacji skanera i pliku nag³ówkowego parsera
OBJLY = $(patsubst %, %.yy.o, $(YACC))

all:  $(EXE)
	echo $(OBJLY)

%.yy.c:  %.l 
	flex  -o$*.yy.c $*.l

%.tab.c %.tab.h: %.y
	bison -d $*.y

%.tab.o: %.tab.c
	gcc -c $*.tab.c

$(OBJL): %.yy.o : %.yy.c
	gcc -c $*.yy.c 

$(OBJLY): %.yy.o : %.yy.c %.tab.h
	gcc -c $*.yy.c 

$(LEX): %: %.yy.o
	gcc -o $* $*.yy.o -lfl

$(YACC): %: %.yy.o %.tab.o
	gcc -o $* $*.yy.o $*.tab.o -lfl

.PHONY: clean mrproper

mrproper: clean
	rm -f $(EXE)
clean:
	rm -f *~
	rm -f *.yy.c
	rm -f *.tab.c
	rm -f *.tab.h
	rm -f *.o