scanner.l

%{
#include "scanner.h"
%}
%option nounput yylineno

%%

		/* comments in c! */
			/* multi line */
"/*"((("*"[^/])?)|[^*])*"*/" return COMMENT;
			/* single line */
"//".*					return COMMENT;
		/* skip preprocessor lines */
^"#".*					return PREPROCESSOR;
		/*	reserved keywords */
auto					return KEYWORD;
double					return KEYWORD;
int					return KEYWORD;
struct					return KEYWORD;
break					return KEYWORD;
else					return KEYWORD;
long					return KEYWORD;
switch					return KEYWORD;
case					return KEYWORD;
enum					return KEYWORD;
register					return KEYWORD;
typedef					return KEYWORD;
char					return KEYWORD;
extern					return KEYWORD;
return					return KEYWORD;
union					return KEYWORD;
const					return KEYWORD;
float					return KEYWORD;
short					return KEYWORD;
unsigned					return KEYWORD;
continue					return KEYWORD;
for					return KEYWORD;
signed					return KEYWORD;
void					return KEYWORD;
default					return KEYWORD;
goto					return KEYWORD;
sizeof					return KEYWORD;
volatile					return KEYWORD;
do					return KEYWORD;
if					return KEYWORD;
static					return KEYWORD;
while					return KEYWORD;
		/* constants */
			/* decimal */
[-+]?[0-9]+				return CONSTANTLITERAL;
			/* octal */
O[0-9]+					return CONSTANTLITERAL;
			/* hexadecimal */
OX[0-9abcdef]+			return CONSTANTLITERAL;
			/* real(fractional) */
[-+]?[0-9]+(\.[0-9]+)?	return CONSTANTLITERAL;
			/* single character */
'([^\r^\n^']|\\0)'				return CONSTANTCHAR;
			/* strings */
\"[^\"]*\" return CONSTANTSTRING;
			

		/* Identifier (variable names) */
[a-zA-Z_][_a-zA-Z0-9]*	return IDENTIFIER;

		/* operators */
			/* arithmetic */
\+						return OPERATOR;
- 						return OPERATOR;
\* 						return OPERATOR;
\/ 						return OPERATOR;
\%						return OPERATOR;
\+\+						return OPERATOR;
"--"						return OPERATOR;
					
			/* relational */						
==						return OPERATOR;
!=						return OPERATOR;
\> 						return OPERATOR;
\< 						return OPERATOR;
\>=						return OPERATOR;
\<=						return OPERATOR;
			/* logical */						
&&						return OPERATOR;
\|\|						return OPERATOR;
!						return OPERATOR;
			/* bitwise */					
& 						return OPERATOR;
\| 						return OPERATOR;
\^ 						return OPERATOR;
~ 						return OPERATOR;
\<\<						return OPERATOR;
\>\>						return OPERATOR;
			/* misc */					
"?"						return OPERATOR;

			/* punctuators */
\(						return PUNCTUATOR;
\)						return PUNCTUATOR;
\{						return PUNCTUATOR;
\}						return PUNCTUATOR;
\[						return PUNCTUATOR;
\]						return PUNCTUATOR;
,						return PUNCTUATOR;
:						return PUNCTUATOR;
;						return PUNCTUATOR;
=						return PUNCTUATOR;


		/* skip new lines and blank spaces */
[ \t\n]					return BLANK;
		/* everything not defined before is caught here, considered an error */
.						return ERROR;	

%%

int yywrap(void)
{
	return 1;
}