IDL grammar

We show the informal definitions of IDL grammar as follows.

• '...' indicates a literal.

• IDENTIFIER is an identifier, CONSTANT is a constant.

• STRING is one or more character inside double quotation marks("..."). OPT_STRING is a STRING which can be omitted.

• {..}* stands iteration which not less than 0.

• C_PROGRAM stands for any program in C.

• type_specifier are fundamental data types of C, string, filename which stands for file and filepointer which stands for FILE pointer.

program := {declaration}*

declaration:=
          'Module' IDENTIFIER ';'
	| 'Define' interface_definition OPT_STRING interface_body
        | 'Globals' '{' C_PROGRAM '}'
        | 'Fortranformat' STRING ';'
	;

interface_definition:=
  	  IDENTIFIER '(' parameter {',' parameter}* ')'
	;

parameter:= decl_specifier declarator ;

decl_specifier: 
	type_specifier
	| MODE
	| MODE type_specifier
	| type_specifier MODE
	| type_specifier MODE type_specifier
	;

MODE := 'mode_in' | 'IN' | 'mode_out' | 'OUT';

declarator=:
	  IDENTIFIER
	| '(' declarator ')'
	| declarator '['expr_or_null ']'
	| declarator '['expr_or_null ':' range_spec ']'
	| '*' declarator
	;

range_spec=:
  	  expr
	| expr ',' expr
	| expr ',' expr ',' expr
	;

interface_body:
	'{' C_PROGRAM '}'
	| CALLS OPT_STRING IDENTIFIER '(' IDENTIFIER {',' IDEFINTIER}* ')' ';'
	;

expr_or_null:= 	expr | /* null */;

expr:=	  primary_expr
	| '*' expr	/* pointer reference */ 
	| '-' expr	/* unary minus */
	| expr '/' expr
	| expr '%' expr
	| expr '+' expr
	| expr '-' expr
	| expr '*' expr
	| expr '^' expr
	| expr RELOP expr
        | expr '?' expr ':' expr
	;

primary_expr:=
	 primary_expr '[' expr ']'
	| IDENTIFIER
	| CONSTANT
	| '('  expr  ')'
	;