Compiler.y

%{
	#define YYDEBUG 1
	#include<stdio.h>
	#include <stdlib.h>
	void yyerror(const char*);
	int yylex();
%}

%token HASH INCLUDE DEFINE STDIO STDLIB MATH STRING TIME

%token	IDENTIFIER I_CONSTANT F_CONSTANT STRING_LITERAL SIZEOF

%token	PTR_OP INC_OP DEC_OP LE_OP GE_OP EQ_OP NE_OP

%token	AND_OP OR_OP MUL_ASSIGN DIV_ASSIGN MOD_ASSIGN ADD_ASSIGN

%token	SUB_ASSIGN LEFT_ASSIGN RIGHT_ASSIGN AND_ASSIGN

%token	XOR_ASSIGN OR_ASSIGN

%token	TYPEDEF_NAME

%token	TYPEDEF STATIC

%token	CONST

%token	CHAR SHORT INT LONG SIGNED UNSIGNED FLOAT DOUBLE VOID MAIN

%token	STRUCT

%token	IF ELSE FOR 

%token CONTINUE BREAK RETURN

%start translation_unit

%%

headers
	: HASH INCLUDE STRING_LITERAL
	| HASH INCLUDE '<' libraries '>'
	| HASH DEFINE I_CONSTANT
	| HASH DEFINE F_CONSTANT
	;

libraries
	: STDIO
	| STDLIB
	| MATH
	| STRING
	| TIME
	;

primary_expression
	: IDENTIFIER
	| I_CONSTANT
	| F_CONSTANT
	| STRING_LITERAL
	| '(' expression ')'
	;

postfix_expression
	: primary_expression
	| postfix_expression '[' expression ']'
	| postfix_expression '(' ')'
	| postfix_expression '(' argument_expression_list ')'
	| postfix_expression '.' IDENTIFIER
	| postfix_expression PTR_OP IDENTIFIER
	| postfix_expression INC_OP
	| postfix_expression DEC_OP
	;

argument_expression_list
	: assignment_expression
	| argument_expression_list ',' assignment_expression
	;

unary_expression
	: postfix_expression
	| INC_OP unary_expression
	| DEC_OP unary_expression
	| unary_operator cast_expression
	| SIZEOF unary_expression
	| SIZEOF '(' specifier_qualifier_list ')'
	;

unary_operator
	: '&'
	| '*'
	| '+'
	| '-'
	| '~'
	| '!'
	;

cast_expression
	: unary_expression
	| '(' specifier_qualifier_list ')' cast_expression
	;

multiplicative_expression
	: cast_expression
	| multiplicative_expression '*' cast_expression
	| multiplicative_expression '/' cast_expression
	| multiplicative_expression '%' cast_expression
	;

additive_expression
	: multiplicative_expression
	| additive_expression '+' multiplicative_expression
	| additive_expression '-' multiplicative_expression
	;

relational_expression
	: additive_expression
	| relational_expression '<' additive_expression
	| relational_expression '>' additive_expression
	| relational_expression LE_OP additive_expression
	| relational_expression GE_OP additive_expression
	;

equality_expression
	: relational_expression
	| equality_expression EQ_OP relational_expression
	| equality_expression NE_OP relational_expression
	;

and_expression
	: equality_expression
	| and_expression '&' equality_expression
	;

exclusive_or_expression
	: and_expression
	| exclusive_or_expression '^' and_expression
	;

inclusive_or_expression
	: exclusive_or_expression
	| inclusive_or_expression '|' exclusive_or_expression
	;

logical_and_expression
	: inclusive_or_expression
	| logical_and_expression AND_OP inclusive_or_expression
	;

logical_or_expression
	: logical_and_expression
	| logical_or_expression OR_OP logical_and_expression
	;

conditional_expression
	: logical_or_expression
	| logical_or_expression '?' expression ':' conditional_expression
	;

assignment_expression
	: conditional_expression
	| unary_expression assignment_operator assignment_expression
	;

assignment_operator
	: '='
	| MUL_ASSIGN
	| DIV_ASSIGN
	| MOD_ASSIGN
	| ADD_ASSIGN
	| SUB_ASSIGN
	| AND_ASSIGN
	| XOR_ASSIGN
	| OR_ASSIGN
	;

expression
	: assignment_expression
	| expression ',' assignment_expression
	;

constant_expression
	: conditional_expression	/* with constraints */
	;

declaration
	: declaration_specifiers ';'
	| declaration_specifiers init_declarator_list ';'
	;

declaration_specifiers
	: storage_class_specifier declaration_specifiers
	| storage_class_specifier
	| type_specifier declaration_specifiers
	| type_specifier
	| CONST declaration_specifiers
	| CONST
	;

init_declarator_list
	: init_declarator
	| init_declarator_list ',' init_declarator
	;

init_declarator
	: declarator '=' assignment_expression
	| declarator
	;

storage_class_specifier
	: TYPEDEF	/* identifiers must be flagged as TYPEDEF_NAME */
	| STATIC
	;

type_specifier
	: VOID
	| CHAR
	| SHORT
	| INT
	| LONG
	| FLOAT
	| DOUBLE
	| SIGNED
	| UNSIGNED
	| struct_specifier
	| TYPEDEF_NAME		/* after it has been defined as such */
	;

struct_specifier
	: STRUCT '{' struct_declaration_list '}'
	| STRUCT IDENTIFIER '{' struct_declaration_list '}'
	| STRUCT IDENTIFIER
	;

struct_declaration_list
	: struct_declaration
	| struct_declaration_list struct_declaration
	;

struct_declaration
	: specifier_qualifier_list ';'	/* for anonymous struct/union */
	| specifier_qualifier_list struct_declarator_list ';'
	;

specifier_qualifier_list
	: type_specifier specifier_qualifier_list
	| type_specifier
	| CONST specifier_qualifier_list
	| CONST
	;

struct_declarator_list
	: struct_declarator
	| struct_declarator_list ',' struct_declarator
	;

struct_declarator
	: ':' constant_expression
	| declarator ':' constant_expression
	| declarator
	;

declarator
	: pointer IDENTIFIER
	| IDENTIFIER
	;

pointer
	: '*' CONST pointer
	| '*' CONST
	| '*' pointer
	| '*'
	;

statement
	: compound_statement
	| expression_statement
	| iteration_statement
	| jump_statement
	;

compound_statement
	: '{' '}'
	| '{'  block_item_list '}'
	;

block_item_list
	: block_item
	| block_item_list block_item
	;

block_item
	: declaration
	| statement
	;

expression_statement
	: ';'
	| expression ';'
	;

iteration_statement
	: FOR '(' expression_statement expression_statement ')' statement
	| FOR '(' expression_statement expression_statement expression ')' statement
	| FOR '(' declaration expression_statement ')' statement
	| FOR '(' declaration expression_statement expression ')' statement
	;

jump_statement
	: CONTINUE ';'
	| BREAK ';'
	| RETURN ';'
	| RETURN expression ';'
	;

translation_unit
	: external_declaration
	| translation_unit external_declaration
	;

external_declaration
	: INT MAIN '(' ')' compound_statement
	| declaration
	| headers
	;

%%
void yyerror(const char *str)
{
	fflush(stdout);
	fprintf(stderr, "*** %s\n", str);
}
int main(){
	if(!yyparse())
		printf("Successful\n");
	else
		printf("Unsuccessful\n");
	
	return 0;
}