/* cctr2.y  MR 20/09/98
   Input file to 'bison' (or 'yacc') to generate a parser that parses the 
   output ascii file as generated by running '../lexan/clscanc1.sh' on a
   C source file, and produces a calling tree as output (= which function
   calls which function).
   How to generate the parser program:
       1) Run bison on this file:     bison cctr2.y
       2) Compile the bison output:   gcc cctr2.tab.c -o cctr2
*/
%{
int GLOBlinenr = 0;
#define NAMESZ 40 
typedef struct { char buf[NAMESZ]; } name_t; 
name_t GLOBfname;
name_t GLOBnullname;
#define YYSTYPE name_t
%}
%token ID
%token OTHER
%start sourcecode
%%
sourcecode     : /* empty */
               | sourcecode declaration
               | sourcecode definition
;
seqother       : /*empty*/
               | seqother OTHER
;
type           : ID
               | type ID
               | type '*' 
;
arrdecl        : /*empty*/
               | '[' ']'
;
initializer    : /*empty*/
               | '=' ID         /* "= value" */
               | '=' OP ID      /* "= -value" */
               | '=' '{' valuelist '}'
;
valuelist      : ID
               | OP ID                   /* "-value" */
               | valuelist ',' ID
               | valuelist ',' OP ID     /* ", -value" */
               | valuelist ',' '{' valuelist '}'
;
definition     : type ID arrdecl initializer ';' 
                      { 
                      name_t tmp = $2;
                      printf( "globalvar-def '%s'\n", tmp.buf ); 
                      }
               | type ID HxxxH '{' 
                      { 
                      name_t tmp = $2;
                      printf( "func-def-begin '%s'\n", tmp.buf ); 
                      GLOBfname = tmp;
                      }
                 body '}' 
                      {
                      name_t tmp = $1;
                      printf( "func-def-end '%s'\n", tmp.buf ); 
                      GLOBfname = GLOBnullname; 
                      }
;
declaration    : type ID '(' formalParList ')' ';' 
                      { 
                      name_t tmp = $2;
                      printf( "func-decl '%s'\n", tmp.buf ); 
                      }
;
formalParList  : /*empty*/
               | nonemptyFPlist
;
nonemptyFPlist : type ID
               | nonemptyFPlist ',' type ID
;
body           : /*empty*/
               | body stmt
;
stmt           : ';'
               | expr ';'
;
expr           : atom
               | expr OP atom
;
atom           : ID
               | funccall
               | '(' expr ')'
;
funccall       : ID '(' actualParList ')'  
                      { 
                      name_t tmp = $1;
                      printf( "func-call '%s' in function '%s'\n", 
                         tmp.buf, GLOBfname.buf ); 
                      }
;
actualParList  : /*empty*/
               | nonemptyAPlist
;
nonemptyAPlist : expr
               | nonemptyAPlist ',' expr
;
%%
#if 0
             | OP expr 
             | expr '[' expr ']'
             | '(' ID ')' expr   /*type cast*/
#endif
#include <stdio.h>
#include <string.h>
main()
	{
	strcpy( GLOBnullname.buf, "null" ); 
	GLOBfname = GLOBnullname;
	yyparse();
	}
yyerror( char * str )
	{
	printf( "cctr2(%d): %s\n", GLOBlinenr, str );
	}
#define BUFSZ 256
int yylex( void )
	{
	char buf[BUFSZ];
	int len;
	if ( GLOBlinenr++,
	   ! fgets( buf, sizeof(buf), stdin ) )
		{
		return 0; /* At EOF */
		}
	len = strlen( buf );
	if ( buf[len-1] == '\n' ) { buf[len-1] = '\0'; }
	/* Discriminate only between: 
                  identifier
                  {
                  }
                  (
                  )
                  ;
                  anything else
	*/
	if ( buf[0] == 'I' )
		{
		name_t tmp;
		strncpy( tmp.buf, buf+1, NAMESZ-1 );
		yylval = tmp;
		return ID;
		}
	else if ( buf[0] == ';' || buf[0] == '{' || buf == '}' ||
		  buf[0] == '(' || buf[0] == ')' )
		{
		return buf[0];
		}
	else
		{
		return OTHER;
		}
	}