%{
  #include "prototypes.h"
%}
%token IDENTIFIER CONSTANT STRING_LITERAL SIZEOF
%token PTR_OP INC_OP DEC_OP LEFT_OP RIGHT_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 TYPE_NAME

%token TYPEDEF EXTERN STATIC AUTO REGISTER
%token CHAR SHORT INT LONG SIGNED UNSIGNED FLOAT DOUBLE CONST VOLATILE VOID
%token STRUCT UNION ENUM ELIPSIS RANGE

%token CASE DEFAULT IF ELSE SWITCH WHILE DO FOR GOTO CONTINUE BREAK RETURN

%start file
%%

primary_expr
  : identifier
  | CONSTANT
  | STRING_LITERAL
  | '(' expr ')'
  ;

postfix_expr
  : primary_expr
  | postfix_expr '[' expr ']'
  | postfix_expr '(' ')'
  | postfix_expr '(' argument_expr_list ')'
  | postfix_expr '.' identifier
  | postfix_expr PTR_OP identifier
  | postfix_expr INC_OP
  | postfix_expr DEC_OP
  ;

argument_expr_list
  : assignment_expr
  | argument_expr_list ',' assignment_expr
  ;

unary_expr
  : postfix_expr
  | INC_OP unary_expr
  | DEC_OP unary_expr
  | unary_operator cast_expr
  | SIZEOF unary_expr
  | SIZEOF '(' type_name ')'
  ;

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

cast_expr
  : unary_expr
  | '(' type_name ')' cast_expr
  ;

multiplicative_expr
  : cast_expr
  | multiplicative_expr '*' cast_expr
  | multiplicative_expr '/' cast_expr
  | multiplicative_expr '%' cast_expr
  ;

additive_expr
  : multiplicative_expr
  | additive_expr '+' multiplicative_expr
  | additive_expr '-' multiplicative_expr
  ;

shift_expr
  : additive_expr
  | shift_expr LEFT_OP additive_expr
  | shift_expr RIGHT_OP additive_expr
  ;

relational_expr
  : shift_expr
  | relational_expr '<' shift_expr
  | relational_expr '>' shift_expr
  | relational_expr LE_OP shift_expr
  | relational_expr GE_OP shift_expr
  ;

equality_expr
  : relational_expr
  | equality_expr EQ_OP relational_expr
  | equality_expr NE_OP relational_expr
  ;

and_expr
  : equality_expr
  | and_expr '&' equality_expr
  ;

exclusive_or_expr
  : and_expr
  | exclusive_or_expr '^' and_expr
  ;

inclusive_or_expr
  : exclusive_or_expr
  | inclusive_or_expr '|' exclusive_or_expr
  ;

logical_and_expr
  : inclusive_or_expr
  | logical_and_expr AND_OP inclusive_or_expr
  ;

logical_or_expr
  : logical_and_expr
  | logical_or_expr OR_OP logical_and_expr
  ;

conditional_expr
  : logical_or_expr
  | logical_or_expr '?' logical_or_expr ':' conditional_expr
  ;

assignment_expr
  : conditional_expr
  | unary_expr assignment_operator assignment_expr
  ;

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

expr
  : assignment_expr
  | expr ',' assignment_expr
  ;

constant_expr
  : conditional_expr
  ;

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

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

init_declarator_list
  : init_declarator
  | init_declarator_list ',' init_declarator
  ;

init_declarator
  : declarator
  | declarator '=' initializer
  ;

storage_class_specifier
  : TYPEDEF
  | EXTERN
  | STATIC
  | AUTO
  | REGISTER
  ;

type_specifier
  : CHAR
  | SHORT
  | INT
  | LONG
  | SIGNED
  | UNSIGNED
  | FLOAT
  | DOUBLE
  | CONST
  | VOLATILE
  | VOID
  | struct_or_union_specifier
  | enum_specifier
  | TYPE_NAME
  ;

struct_or_union_specifier
  : struct_or_union identifier '{' struct_declaration_list '}'
  | struct_or_union '{' struct_declaration_list '}'
  | struct_or_union identifier
  ;

struct_or_union
  : STRUCT
  | UNION
  ;

struct_declaration_list
  : struct_declaration
  | struct_declaration_list struct_declaration
  ;

struct_declaration
  : type_specifier_list struct_declarator_list ';'
  ;

struct_declarator_list
  : struct_declarator
  | struct_declarator_list ',' struct_declarator
  ;

struct_declarator
  : declarator
  | ':' constant_expr
  | declarator ':' constant_expr
  ;

enum_specifier
  : ENUM '{' enumerator_list '}'
  | ENUM identifier '{' enumerator_list '}'
  | ENUM identifier
  ;

enumerator_list
  : enumerator
  | enumerator_list ',' enumerator
  ;

enumerator
  : identifier
  | identifier '=' constant_expr
  ;

declarator
  : declarator2
  | pointer declarator2
  ;

declarator2
  : identifier
  | '(' declarator ')'
  | declarator2 '[' ']'
  | declarator2 '[' constant_expr ']'
  | declarator2 '(' ')'
  | declarator2 '(' parameter_type_list ')'
  | declarator2 '(' parameter_identifier_list ')'
  ;

pointer
  : '*'
  | '*' type_specifier_list
  | '*' pointer
  | '*' type_specifier_list pointer
  ;

type_specifier_list
  : type_specifier
  | type_specifier_list type_specifier
  ;

parameter_identifier_list
  : identifier_list
  | identifier_list ',' ELIPSIS
  ;

identifier_list
  : identifier
  | identifier_list ',' identifier
  ;

parameter_type_list
  : parameter_list
  | parameter_list ',' ELIPSIS
  ;

parameter_list
  : parameter_declaration
  | parameter_list ',' parameter_declaration
  ;

parameter_declaration
  : type_specifier_list declarator
  | type_name
  ;

type_name
  : type_specifier_list
  | type_specifier_list abstract_declarator
  ;

abstract_declarator
  : pointer
  | abstract_declarator2
  | pointer abstract_declarator2
  ;

abstract_declarator2
  : '(' abstract_declarator ')'
  | '[' ']'
  | '[' constant_expr ']'
  | abstract_declarator2 '[' ']'
  | abstract_declarator2 '[' constant_expr ']'
  | '(' ')'
  | '(' parameter_type_list ')'
  | abstract_declarator2 '(' ')'
  | abstract_declarator2 '(' parameter_type_list ')'
  ;

initializer
  : assignment_expr
  | '{' initializer_list '}'
  | '{' initializer_list ',' '}'
  ;

initializer_list
  : initializer
  | initializer_list ',' initializer
  ;

statement
  : labeled_statement
  | compound_statement
  | expression_statement
  | selection_statement
  | iteration_statement
  | jump_statement
  ;

labeled_statement
  : identifier ':' statement
  | CASE constant_expr ':' statement
  | DEFAULT ':' statement
  ;

compound_statement
  : '{' '}'
  | '{' statement_list '}'
  | '{' declaration_list '}'
  | '{' declaration_list statement_list '}'
  ;

declaration_list
  : declaration
  | declaration_list declaration
  ;

statement_list
  : statement
  | statement_list statement
  ;

expression_statement
  : ';'
  | expr ';'
  ;

selection_statement
  : IF '(' expr ')' statement
  | IF '(' expr ')' statement ELSE statement
  | SWITCH '(' expr ')' statement
  ;

iteration_statement
  : WHILE '(' expr ')' statement
  | DO statement WHILE '(' expr ')' ';'
  | FOR '(' ';' ';' ')' statement
  | FOR '(' ';' ';' expr ')' statement
  | FOR '(' ';' expr ';' ')' statement
  | FOR '(' ';' expr ';' expr ')' statement
  | FOR '(' expr ';' ';' ')' statement
  | FOR '(' expr ';' ';' expr ')' statement
  | FOR '(' expr ';' expr ';' ')' statement
  | FOR '(' expr ';' expr ';' expr ')' statement
  ;

jump_statement
  : GOTO identifier ';'
  | CONTINUE ';'
  | BREAK ';'
  | RETURN ';'
  | RETURN expr ';'
  ;

file
  : external_definition
  | file external_definition
  ;

external_definition
  : function_definition
  | declaration
  ;

function_definition
  : declarator function_body
  | declaration_specifiers declarator function_body
  ;

function_body
  : compound_statement
  | declaration_list compound_statement
  ;

identifier
  : IDENTIFIER
  ;
%%

#include <stdio.h>

extern YYSTYPE yytext;
extern int column;

void yyerror(char *s)
{
  fflush(stdout);
  printf("[%4d]: %s\n", column, yytext);
  printf("\n%*s\n%*s\n", column, "^", column, s);
}