C_lang_lex.l

/*Lex File*/
L			[a-zA-Z_]
H			[a-fA-F0-9]
E			[Ee][+-]?{D}+
D			[0-9]
FS			(f|F|l|L)
IS			(u|U|l|L)*

%{
#include <stdio.h>
#include "y.tab.h"
void count();
extern int line_number;
%}

%%
"#"				{ head();}
"/*"			{ comment(); }
"\n"			{ line_number++;  }
"auto"			{ count();   return(AUTO);}
"break"			{ count();   return(BREAK);}
"case"			{ count();    return(CASE); }
"char"			{ count();     return(CHAR);}
"const"			{ count();     return(CONST);}
"continue"		{ count();     return(CONTINUE);}
"default"		{ count();     return(DEFAULT);}
"do"			{ count();     return(DO);}
"double"		{ count();     return(DOUBLE);}
"else"			{ count();     return(ELSE);}
"enum"			{ count();     return(ENUM);}
"extern"		{ count();     return(EXTERN);}
"float"			{ count();     return(FLOAT);}
"for"			{ count();     return(FOR);}
"goto"			{ count();     return(GOTO);}
"if"			{ count();     return(IF);}
"int"			{ count();     return(INT);}
"long"			{ count();     return(LONG);}
"register"		{ count();     return(REGISTER);}
"return"		{ count();    return(RETURN);}
"short"			{ count();     return(SHORT);}
"signed"		{ count();     return(SIGNED);}
"sizeof"		{ count();     return(SIZEOF);}
"static"		{ count();     return(STATIC);}
"struct"		{ count();     return(STRUCT);}
"switch"		{ count();     return(SWITCH);}
"typedef"		{ count();     return(TYPEDEF);}
"union"			{ count();     return(UNION);}
"unsigned"		{ count();     return(UNSIGNED);}
"void"			{ count();     return(VOID);}
"volatile"		{ count();     return(VOLATILE);}
"while"			{ count();     return(WHILE);}

{L}({L}|{D})*		{ count();   return(check_type()); }

0[xX]{H}+{IS}?		{ count();   return(CONSTANT); }
0{D}+{IS}?		{ count();   return(CONSTANT); }
{D}+{IS}?		{ count();   return(CONSTANT); }
L?'(\\.|[^\\'])+'	{ count();   return(CONSTANT); }

{D}+{E}{FS}?		{ count();   return(CONSTANT); }
{D}*"."{D}+({E})?{FS}?	{ count();   return(CONSTANT); }
{D}+"."{D}*({E})?{FS}?	{ count();   return(CONSTANT); }

L?\"(\\.|[^\\"])*\"	{ count();   return(STRING_LITERAL); }

"..."			{ count();   return(ELLIPSIS); }
">>="			{ count();   return(RIGHT_ASSIGN); }
"<<="			{ count();   return(LEFT_ASSIGN); }
"+="			{ count();   return(ADD_ASSIGN); }
"-="			{ count();   return(SUB_ASSIGN); }
"*="			{ count();   return(MUL_ASSIGN); }
"/="			{ count();   return(DIV_ASSIGN); }
"%="			{ count();   return(MOD_ASSIGN); }
"&="			{ count();   return(AND_ASSIGN); }
"^="			{ count();   return(XOR_ASSIGN); }
"|="			{ count();   return(OR_ASSIGN); }
">>"			{ count();   return(RIGHT_OP); }
"<<"			{ count();   return(LEFT_OP); }
"++"			{ count();   return(INC_OP); }
"--"			{ count();   return(DEC_OP); }
"->"			{ count();   return(PTR_OP); }
"&&"			{ count();   return(AND_OP); }
"||"			{ count();   return(OR_OP); }
"<="			{ count();   return(LE_OP); }
">="			{ count();   return(GE_OP); }
"=="			{ count();   return(EQ_OP); }
"!="			{ count();   return(NE_OP); }
";"			{ count();   return(';'); }
("{"|"<%")		{ count();   return('{'); }
("}"|"%>")		{ count();   return('}'); }
","			{ count();   return(','); }
":"			{ count();   return(':'); }
"="			{ count();   return('='); }
"("			{ count();   return('('); }
")"			{ count();   return(')'); }
("["|"<:")		{ count();   return('['); }
("]"|":>")		{ count();   return(']'); }
"."			{ count();   return('.'); }
"&"			{ count();   return('&'); }
"!"			{ count();   return('!'); }
"~"			{ count();   return('~'); }
"-"			{ count();   return('-'); }
"+"			{ count();   return('+'); }
"*"			{ count();   return('*'); }
"/"			{ count();   return('/'); }
"%"			{ count();   return('%'); }
"<"			{ count();   return('<'); }
">"			{ count();   return('>'); }
"^"			{ count();   return('^'); }
"|"			{ count();   return('|'); }
"?"			{ count();   return('?'); }

[ \t\v\n\f]		{ count();   }
.			{ /* ignore bad characters */ }

%%
	
int yywrap()
{
	return(1);
}

head(){
	char c;
	while((c=input())!='>')
		putchar(c);
		}
comment()
{
	char c, c1;

	loop:
		while ((c = input()) != '*' && c != 0)
			putchar(c);
	
		if ((c1 = input()) != '/' && c != 0)
		{
			unput(c1);
			goto loop;
		}

	if (c != 0)
		putchar(c1);
}


int column = 0;

void count()
{
	int i;

	for (i = 0; yytext[i] != '\0'; i++)
		if (yytext[i] == '\n')
			column = 0;
		else if (yytext[i] == '\t')
			column += 8 - (column % 8);
		else
			column++;
			
	ECHO;

}

char *strdup();
int check_type()
{
/*
* pseudo code --- this is what it should check
*
*	if (yytext == type_name)
*		return(TYPE_NAME);
*
*	return(IDENTIFIER);
*/

/*
*	it actually will only return IDENTIFIER
*/
// printf("\nLEX IDENTIFIER yytext is ==%s==\n", yytext);
yylval.text = strdup(yytext);
if(is_symbol(yylval.text)){
printf("returning typename\n");
	return(TYPE_NAME);
}
return(IDENTIFIER);
}