#include	"defs.h"

#define ARGMAX 32
#define ARGLEN 512

STATIC STRING	arglist[ARGMAX];
STATIC CHAR	argchar[ARGLEN];
STATIC CHAR	*argc;

/*
 * io library
 *
 * S. R. Bourne
 * Bell Telephone Laboratories
 *
 */


INT	word()
{
	REG STRING argp=argc;
	REG INT	c;

	/* ignore initial white space */
	WHILE (c=readc())!=EOF ANDF space(c) DO ; OD

	IF idchar(c)
	THEN	REP	*argp++=(c);
		PER (c=readc())!=EOF ANDF idchar(c) DONE
		IF c!=','
		THEN backspace(standin);
		FI
		c=',';

	ELIF c=='%'
	THEN	WHILE (c=readc())!=NL ANDF c!=EOF DONE
	ELIF c!=',' ANDF c!=NL ANDF c!=';' ANDF c!=EOF
	THEN	*argp++=c;
	FI
	*argp++=0;
	argc=argp;
	return(c);
}

INT	args()
{
	REG INT c;
	REG STRING argp;
	REG STRING *argl;

	argc=argp=argchar; argl=arglist;
	WHILE (c=word())!=EOF ANDF c!=NL ANDF c!=';'
	DO *argl++ = argp;
	   IF argl-arglist >= ARGMAX
	   THEN argl--;
	   FI
	   argp=argc;
	OD
	
	*argl = nil(STRING);
	return(c);
}

INT	cmdtyp;
STRING *chknxt(src)
	REG STRING *src;
{
	REG STRING s;

	/* make sure .c precedes .ch etc */
	IF (s = *src) ANDF s[0]=='.'
	THEN	IF s[2]==0
		THEN	cmdtyp=s[1];
		ELIF s[1]!=cmdtyp
		THEN	src = PARSERR;
		FI
	FI
	return(src);
}

STRING *parse(chk)
{
	REG INT	a;
	REG STRING *src;

	WHILE (a=args())!=EOF ANDF arglist[0]==nil(STRING) DONE

	src = (a!=EOF)?arglist:nil(STRING*);
	if(chk && src)
		src=chknxt(src);
	return(src);
}