[unix-history] / usr / src / cmd / bc.y

%{
	int *getout();
%}
%right '='
%left '+' '-'
%left '*' '/' '%'
%right '^'
%left UMINUS

%term LETTER DIGIT SQRT LENGTH _IF  FFF EQ
%term _WHILE _FOR NE LE GE INCR DECR
%term _RETURN _BREAK _DEFINE BASE OBASE SCALE
%term EQPL EQMI EQMUL EQDIV EQREM EQEXP
%term _AUTO DOT
%term QSTR

%{
#include <stdio.h>
int in;
char cary[1000], *cp = { cary };
char string[1000], *str = {string};
int crs = '0';
int rcrs = '0';  /* reset crs */
int bindx = 0;
int lev = 0;
int ln;
char *ss;
int bstack[10] = { 0 };
char *numb[15] = {
  " 0", " 1", " 2", " 3", " 4", " 5",
  " 6", " 7", " 8", " 9", " 10", " 11",
  " 12", " 13", " 14" };
int *pre, *post;
%}
%%
start	: 
	|  start stat tail
		= output( $2 );
	|  start def dargs ')' '{' dlist slist '}'
		={	bundle( 6,pre, $7, post ,"0",numb[lev],"Q");
			conout( $$, $2 );
			rcrs = crs;
			output( "" );
			lev = bindx = 0;
			}
	;

dlist	:  tail
	| dlist _AUTO dlets tail
	;

stat	:  e 
		={ bundle(2, $1, "ps." ); }
	| 
		={ bundle(1, "" ); }
	|  QSTR
		={ bundle(3,"[",$1,"]P");}
	|  LETTER '=' e
		={ bundle(3, $3, "s", $1 ); }
	|  LETTER '[' e ']' '=' e
		={ bundle(4, $6, $3, ":", geta($1)); }
	|  LETTER EQOP e
		={ bundle(6, "l", $1, $3, $2, "s", $1 ); }
	|  LETTER '[' e ']' EQOP e
		={ bundle(8,$3, ";", geta($1), $6, $5, $3, ":", geta($1));}
	|  _BREAK
		={ bundle(2, numb[lev-bstack[bindx-1]], "Q" ); }
	|  _RETURN '(' e ')'
		= bundle(4, $3, post, numb[lev], "Q" );
	|  _RETURN '(' ')'
		= bundle(4, "0", post, numb[lev], "Q" );
	| _RETURN
		= bundle(4,"0",post,numb[lev],"Q");
	| SCALE '=' e
		= bundle(2, $3, "k");
	| SCALE EQOP e
		= bundle(4,"K",$3,$2,"k");
	| BASE '=' e
		= bundle(2,$3, "i");
	| BASE EQOP e
		= bundle(4,"I",$3,$2,"i");
	| OBASE '=' e
		= bundle(2,$3,"o");
	| OBASE EQOP e
		= bundle(4,"O",$3,$2,"o");
	|  '{' slist '}'
		={ $$ = $2; }
	|  FFF
		={ bundle(1,"fY"); }
	|  error
		={ bundle(1,"c"); }
	|  _IF CRS BLEV '(' re ')' stat
		={	conout( $7, $2 );
			bundle(3, $5, $2, " " );
			}
	|  _WHILE CRS '(' re ')' stat BLEV
		={	bundle(3, $6, $4, $2 );
			conout( $$, $2 );
			bundle(3, $4, $2, " " );
			}
	|  fprefix CRS re ';' e ')' stat BLEV
		={	bundle(5, $7, $5, "s.", $3, $2 );
			conout( $$, $2 );
			bundle(5, $1, "s.", $3, $2, " " );
			}
	|  '~' LETTER '=' e
		={	bundle(3,$4,"S",$2); }
	;

EQOP	:  EQPL
		={ $$ = "+"; }
	|  EQMI
		={ $$ = "-"; }
	|  EQMUL
		={ $$ = "*"; }
	|  EQDIV
		={ $$ = "/"; }
	|  EQREM
		={ $$ = "%%"; }
	|  EQEXP
		={ $$ = "^"; }
	;

fprefix	:  _FOR '(' e ';'
		={ $$ = $3; }
	;

BLEV	:
		={ --bindx; }
	;

slist	:  stat
	|  slist tail stat
		={ bundle(2, $1, $3 ); }
	;

tail	:  '\n'
		={ln++;}
	|  ';'
	;

re	:  e EQ e
		= bundle(3, $1, $3, "=" );
	|  e '<' e
		= bundle(3, $1, $3, ">" );
	|  e '>' e
		= bundle(3, $1, $3, "<" );
	|  e NE e
		= bundle(3, $1, $3, "!=" );
	|  e GE e
		= bundle(3, $1, $3, "!>" );
	|  e LE e
		= bundle(3, $1, $3, "!<" );
	|  e
		= bundle(2, $1, " 0!=" );
	;

e	:  e '+' e
		= bundle(3, $1, $3, "+" );
	|  e '-' e
		= bundle(3, $1, $3, "-" );
	| '-' e		%prec UMINUS
		= bundle(3, " 0", $2, "-" );
	|  e '*' e
		= bundle(3, $1, $3, "*" );
	|  e '/' e
		= bundle(3, $1, $3, "/" );
	|  e '%' e
		= bundle(3, $1, $3, "%%" );
	|  e '^' e
		= bundle(3, $1, $3, "^" );
	|  LETTER '[' e ']'
		={ bundle(3,$3, ";", geta($1)); }
	|  LETTER INCR
		= bundle(4, "l", $1, "d1+s", $1 );
	|  INCR LETTER
		= bundle(4, "l", $2, "1+ds", $2 );
	|  DECR LETTER
		= bundle(4, "l", $2, "1-ds", $2 );
	|  LETTER DECR
		= bundle(4, "l", $1, "d1-s", $1 );
	| LETTER '[' e ']' INCR
		= bundle(7,$3,";",geta($1),"d1+",$3,":",geta($1));
	| INCR LETTER '[' e ']'
		= bundle(7,$4,";",geta($2),"1+d",$4,":",geta($2));
	| LETTER '[' e ']' DECR
		= bundle(7,$3,";",geta($1),"d1-",$3,":",geta($1));
	| DECR LETTER '[' e ']'
		= bundle(7,$4,";",geta($2),"1-d",$4,":",geta($2));
	| SCALE INCR
		= bundle(1,"Kd1+k");
	| INCR SCALE
		= bundle(1,"K1+dk");
	| SCALE DECR
		= bundle(1,"Kd1-k");
	| DECR SCALE
		= bundle(1,"K1-dk");
	| BASE INCR
		= bundle(1,"Id1+i");
	| INCR BASE
		= bundle(1,"I1+di");
	| BASE DECR
		= bundle(1,"Id1-i");
	| DECR BASE
		= bundle(1,"I1-di");
	| OBASE INCR
		= bundle(1,"Od1+o");
	| INCR OBASE
		= bundle(1,"O1+do");
	| OBASE DECR
		= bundle(1,"Od1-o");
	| DECR OBASE
		= bundle(1,"O1-do");
	|  LETTER '(' cargs ')'
		= bundle(4, $3, "l", getf($1), "x" );
	|  LETTER '(' ')'
		= bundle(3, "l", getf($1), "x" );
	|  cons
		={ bundle(2, " ", $1 ); }
	|  DOT cons
		={ bundle(2, " .", $2 ); }
	|  cons DOT cons
		={ bundle(4, " ", $1, ".", $3 ); }
	|  cons DOT
		={ bundle(3, " ", $1, "." ); }
	|  DOT
		={ $$ = "l."; }
	|  LETTER
		= { bundle(2, "l", $1 ); }
	|  LETTER '=' e
		={ bundle(3, $3, "ds", $1 ); }
	|  LETTER EQOP e	%prec '='
		={ bundle(6, "l", $1, $3, $2, "ds", $1 ); }
	| LETTER '[' e ']' '=' e
		= { bundle(5,$6,"d",$3,":",geta($1)); }
	| LETTER '[' e ']' EQOP e
		= { bundle(9,$3,";",geta($1),$6,$5,"d",$3,":",geta($1)); }
	| LENGTH '(' e ')'
		= bundle(2,$3,"Z");
	| SCALE '(' e ')'
		= bundle(2,$3,"X");	/* must be before '(' e ')' */
	|  '(' e ')'
		= { $$ = $2; }
	|  '?'
		={ bundle(1, "?" ); }
	|  SQRT '(' e ')'
		={ bundle(2, $3, "v" ); }
	| '~' LETTER
		={ bundle(2,"L",$2); }
	| SCALE '=' e
		= bundle(2,$3,"dk");
	| SCALE EQOP e		%prec '='
		= bundle(4,"K",$3,$2,"dk");
	| BASE '=' e
		= bundle(2,$3,"di");
	| BASE EQOP e		%prec '='
		= bundle(4,"I",$3,$2,"di");
	| OBASE '=' e
		= bundle(2,$3,"do");
	| OBASE EQOP e		%prec '='
		= bundle(4,"O",$3,$2,"do");
	| SCALE
		= bundle(1,"K");
	| BASE
		= bundle(1,"I");
	| OBASE
		= bundle(1,"O");
	;

cargs	:  eora
	|  cargs ',' eora
		= bundle(2, $1, $3 );
	;
eora:	  e
	| LETTER '[' ']'
		=bundle(2,"l",geta($1));
	;

cons	:  constant
		={ *cp++ = '\0'; }

constant:
	  '_'
		={ $$ = cp; *cp++ = '_'; }
	|  DIGIT
		={ $$ = cp; *cp++ = $1; }
	|  constant DIGIT
		={ *cp++ = $2; }
	;

CRS	:
		={ $$ = cp; *cp++ = crs++; *cp++ = '\0';
			if(crs == '[')crs=+3;
			if(crs == 'a')crs='{';
			if(crs >= 0241){yyerror("program too big");
				getout();
			}
			bstack[bindx++] = lev++; }
	;

def	:  _DEFINE LETTER '('
		={	$$ = getf($2);
			pre = "";
			post = "";
			lev = 1;
			bstack[bindx=0] = 0;
			}
	;

dargs	:
	|  lora
		={ pp( $1 ); }
	|  dargs ',' lora
		={ pp( $3 ); }
	;

dlets	:  lora
		={ tp($1); }
	|  dlets ',' lora
		={ tp($3); }
	;
lora	:  LETTER
	|  LETTER '[' ']'
		={ $$ = geta($1); }
	;

%%
# define error 256

int peekc = -1;
int sargc;
int ifile;
char **sargv;

char funtab[52] = {
	01,0,02,0,03,0,04,0,05,0,06,0,07,0,010,0,011,0,012,0,013,0,014,0,015,0,016,0,017,0,
	020,0,021,0,022,0,023,0,024,0,025,0,026,0,027,0,030,0,031,0,032,0 };
char atab[52] = {
	0241,0,0242,0,0243,0,0244,0,0245,0,0246,0,0247,0,0250,0,0251,0,0252,0,0253,0,
	0254,0,0255,0,0256,0,0257,0,0260,0,0261,0,0262,0,0263,0,0264,0,0265,0,0266,0,
	0267,0,0270,0,0271,0,0272,0};
char *letr[26] = {
  "a","b","c","d","e","f","g","h","i","j",
  "k","l","m","n","o","p","q","r","s","t",
  "u","v","w","x","y","z" } ;
char *dot = { "." };
yylex(){
	int c, ch;
restart:
	c = getch();
	peekc = -1;
	while( c == ' ' || c == '\t' ) c = getch();
	if(c == '\\'){
		getch();
		goto restart;
	}
	if( c<= 'z' && c >= 'a' ) {
		/* look ahead to look for reserved words */
		peekc = getch();
		if( peekc >= 'a' && peekc <= 'z' ){ /* must be reserved word */
			if( c=='i' && peekc=='f' ){ c=_IF; goto skip; }
			if( c=='w' && peekc=='h' ){ c=_WHILE; goto skip; }
			if( c=='f' && peekc=='o' ){ c=_FOR; goto skip; }
			if( c=='s' && peekc=='q' ){ c=SQRT; goto skip; }
			if( c=='r' && peekc=='e' ){ c=_RETURN; goto skip; }
			if( c=='b' && peekc=='r' ){ c=_BREAK; goto skip; }
			if( c=='d' && peekc=='e' ){ c=_DEFINE; goto skip; }
			if( c=='s' && peekc=='c' ){ c= SCALE; goto skip; }
			if( c=='b' && peekc=='a' ){ c=BASE; goto skip; }
			if( c=='i' && peekc == 'b'){ c=BASE; goto skip; }
			if( c=='o' && peekc=='b' ){ c=OBASE; goto skip; }
			if( c=='d' && peekc=='i' ){ c=FFF; goto skip; }
			if( c=='a' && peekc=='u' ){ c=_AUTO; goto skip; }
			if( c == 'l' && peekc=='e'){ c=LENGTH; goto skip; }
			if( c == 'q' && peekc == 'u'){getout();}
			/* could not be found */
			return( error );
		skip:	/* skip over rest of word */
			peekc = -1;
			while( (ch = getch()) >= 'a' && ch <= 'z' );
			peekc = ch;
			return( c );
		}

		/* usual case; just one single letter */

		yylval = letr[c-'a'];
		return( LETTER );
	}
	if( c>= '0' && c <= '9' || c>= 'A' && c<= 'F' ){
		yylval = c;
		return( DIGIT );
	}
	switch( c ){
	case '.':	return( DOT );
	case '=':
		switch( peekc = getch() ){
		case '=': c=EQ; goto gotit;
		case '+': c=EQPL; goto gotit;
		case '-': c=EQMI; goto gotit;
		case '*': c=EQMUL; goto gotit;
		case '/': c=EQDIV; goto gotit;
		case '%': c=EQREM; goto gotit;
		case '^': c=EQEXP; goto gotit;
		default:   return( '=' );
			  gotit:     peekc = -1; return(c);
		  }
	case '+':	return( cpeek( '+', INCR, '+' ) );
	case '-':	return( cpeek( '-', DECR, '-' ) );
	case '<':	return( cpeek( '=', LE, '<' ) );
	case '>':	return( cpeek( '=', GE, '>' ) );
	case '!':	return( cpeek( '=', NE, '!' ) );
	case '/':
		if((peekc = getch()) == '*'){
			peekc = -1;
			while((getch() != '*') || ((peekc = getch()) != '/'));
			peekc = -1;
			goto restart;
		}
		else return(c);
	case '"':	
		 yylval = str;
		 while((c=getch()) != '"'){*str++ = c;
			if(str >= &string[999]){yyerror("string space exceeded");
			getout();
		}
	}
	 *str++ = '\0';
	return(QSTR);
	default:	 return( c );
	}
}

cpeek( c, yes, no ){
	if( (peekc=getch()) != c ) return( no );
	else {
		peekc = -1;
		return( yes );
	}
}

getch(){
	int ch;
loop:
	ch = (peekc < 0) ? getc(in) : peekc;
	peekc = -1;
	if(ch != EOF)return(ch);
	if(++ifile > sargc){
		if(ifile >= sargc+2)getout();
		in = stdin;
		ln = 0;
		goto loop;
	}
	fclose(in);
	if((in = fopen(sargv[ifile],"r")) != NULL){
		ln = 0;
		ss = sargv[ifile];
		goto loop;
	}
	yyerror("cannot open input file");
}
# define b_sp_max 3000
int b_space [ b_sp_max ];
int * b_sp_nxt = { b_space };

int	bdebug = 0;
bundle(a){
	int i, *p, *q;

	p = &a;
	i = *p++;
	q = b_sp_nxt;
	if( bdebug ) printf("bundle %d elements at %o\n",i,  q );
	while(i-- > 0){
		if( b_sp_nxt >= & b_space[b_sp_max] ) yyerror( "bundling space exceeded" );
		* b_sp_nxt++ = *p++;
	}
	* b_sp_nxt++ = 0;
	yyval = q;
	return( q );
}

routput(p) int *p; {
	if( bdebug ) printf("routput(%o)\n", p );
	if( p >= &b_space[0] && p < &b_space[b_sp_max]){
		/* part of a bundle */
		while( *p != 0 ) routput( *p++ );
	}
	else printf( p );	 /* character string */
}

output( p ) int *p; {
	routput( p );
	b_sp_nxt = & b_space[0];
	printf( "\n" );
	fflush(stdout);
	cp = cary;
	crs = rcrs;
}

conout( p, s ) int *p; char *s; {
	printf("[");
	routput( p );
	printf("]s%s\n", s );
	fflush(stdout);
	lev--;
}

yyerror( s ) char *s; {
	if(ifile > sargc)ss="teletype";
	printf("c[%s on line %d, %s]pc\n", s ,ln+1,ss);
	fflush(stdout);
	cp = cary;
	crs = rcrs;
	bindx = 0;
	lev = 0;
	b_sp_nxt = &b_space[0];
}

pp( s ) char *s; {
	/* puts the relevant stuff on pre and post for the letter s */

	bundle(3, "S", s, pre );
	pre = yyval;
	bundle(4, post, "L", s, "s." );
	post = yyval;
}

tp( s ) char *s; { /* same as pp, but for temps */
	bundle(3, "0S", s, pre );
	pre = yyval;
	bundle(4, post, "L", s, "s." );
	post = yyval;
}

yyinit(argc,argv) int argc; char *argv[];{
	signal( 2, (int(*)())1 );	/* ignore all interrupts */
	sargv=argv;
	sargc= -- argc;
	if(sargc == 0)in=stdin;
	else if((in = fopen(sargv[1],"r")) == NULL)
		yyerror("cannot open input file");
	ifile = 1;
	ln = 0;
	ss = sargv[1];
}
int *getout(){
	printf("q");
	fflush(stdout);
	exit();
}

int *
getf(p) char *p;{
	return(&funtab[2*(*p -0141)]);
}
int *
geta(p) char *p;{
	return(&atab[2*(*p - 0141)]);
}

main(argc, argv)
char **argv;
{
	int p[2];


	if (argc > 1 && *argv[1] == '-') {
		if((argv[1][1] == 'd')||(argv[1][1] == 'c')){
			yyinit(--argc, ++argv);
			yyparse();
			exit();
		}
		if(argv[1][1] != 'l'){
			printf("unrecognizable argument\n");
			fflush(stdout);
			exit();
		}
		argv[1] = "/usr/lib/lib.b";
	}
	pipe(p);
	if (fork()==0) {
		close(1);
		dup(p[1]);
		close(p[0]);
		close(p[1]);
		yyinit(argc, argv);
		yyparse();
		exit();
	}
	close(0);
	dup(p[0]);
	close(p[0]);
	close(p[1]);
	execl("/bin/dc", "dc", "-", 0);
	execl("/usr/bin/dc", "dc", "-", 0);
}
Commit	Line	Data
91228447 LC	1	%{
	2	int *getout();
	3	%}
	4	%right '='
	5	%left '+' '-'
	6	%left '*' '/' '%'
	7	%right '^'
	8	%left UMINUS
	9
	10	%term LETTER DIGIT SQRT LENGTH _IF FFF EQ
	11	%term _WHILE _FOR NE LE GE INCR DECR
	12	%term _RETURN _BREAK _DEFINE BASE OBASE SCALE
	13	%term EQPL EQMI EQMUL EQDIV EQREM EQEXP
	14	%term _AUTO DOT
	15	%term QSTR
	16
	17	%{
	18	#include <stdio.h>
	19	int in;
	20	char cary[1000], *cp = { cary };
	21	char string[1000], *str = {string};
	22	int crs = '0';
	23	int rcrs = '0'; /* reset crs */
	24	int bindx = 0;
	25	int lev = 0;
	26	int ln;
	27	char *ss;
	28	int bstack[10] = { 0 };
	29	char *numb[15] = {
	30	" 0", " 1", " 2", " 3", " 4", " 5",
	31	" 6", " 7", " 8", " 9", " 10", " 11",
	32	" 12", " 13", " 14" };
	33	int pre, post;
	34	%}
	35	%%
	36	start :
	37	\| start stat tail
	38	= output( $2 );
	39	\| start def dargs ')' '{' dlist slist '}'
	40	={ bundle( 6,pre, $7, post ,"0",numb[lev],"Q");
	41	conout( $$, $2 );
	42	rcrs = crs;
	43	output( "" );
	44	lev = bindx = 0;
	45	}
	46	;
	47
	48	dlist : tail
	49	\| dlist _AUTO dlets tail
	50	;
	51
	52	stat : e
	53	={ bundle(2, $1, "ps." ); }
	54	\|
	55	={ bundle(1, "" ); }
	56	\| QSTR
	57	={ bundle(3,"[",$1,"]P");}
	58	\| LETTER '=' e
	59	={ bundle(3, $3, "s", $1 ); }
	60	\| LETTER '[' e ']' '=' e
	61	={ bundle(4, $6, $3, ":", geta($1)); }
	62	\| LETTER EQOP e
	63	={ bundle(6, "l", $1, $3, $2, "s", $1 ); }
	64	\| LETTER '[' e ']' EQOP e
65	={ bundle(8,$3, ";", geta($1), $6, $5, $3, ":", geta($1));}
66	\| _BREAK
67	={ bundle(2, numb[lev-bstack[bindx-1]], "Q" ); }
68	\| _RETURN '(' e ')'
69	= bundle(4, $3, post, numb[lev], "Q" );
70	\| _RETURN '(' ')'
71	= bundle(4, "0", post, numb[lev], "Q" );
72	\| _RETURN
73	= bundle(4,"0",post,numb[lev],"Q");
74	\| SCALE '=' e
75	= bundle(2, $3, "k");
76	\| SCALE EQOP e
77	= bundle(4,"K",$3,$2,"k");
78	\| BASE '=' e
79	= bundle(2,$3, "i");
80	\| BASE EQOP e
81	= bundle(4,"I",$3,$2,"i");
82	\| OBASE '=' e
83	= bundle(2,$3,"o");
84	\| OBASE EQOP e
85	= bundle(4,"O",$3,$2,"o");
86	\| '{' slist '}'
87	={ $$ = $2; }
88	\| FFF
89	={ bundle(1,"fY"); }
90	\| error
91	={ bundle(1,"c"); }
92	\| _IF CRS BLEV '(' re ')' stat
93	={ conout( $7, $2 );
94	bundle(3, $5, $2, " " );
95	}
96	\| _WHILE CRS '(' re ')' stat BLEV
97	={ bundle(3, $6, $4, $2 );
98	conout( $$, $2 );
99	bundle(3, $4, $2, " " );
100	}
101	\| fprefix CRS re ';' e ')' stat BLEV
102	={ bundle(5, $7, $5, "s.", $3, $2 );
103	conout( $$, $2 );
104	bundle(5, $1, "s.", $3, $2, " " );
105	}
106	\| '~' LETTER '=' e
107	={ bundle(3,$4,"S",$2); }
108	;
109
110	EQOP : EQPL
111	={ $$ = "+"; }
112	\| EQMI
113	={ $$ = "-"; }
114	\| EQMUL
115	={ $$ = "*"; }
116	\| EQDIV
117	={ $$ = "/"; }
118	\| EQREM
119	={ $$ = "%%"; }
120	\| EQEXP
121	={ $$ = "^"; }
122	;
123
124	fprefix : _FOR '(' e ';'
125	={ $$ = $3; }
126	;
127
128	BLEV :
129	={ --bindx; }
130	;
131
132	slist : stat
133	\| slist tail stat
134	={ bundle(2, $1, $3 ); }
135	;
136
137	tail : '\n'
138	={ln++;}
139	\| ';'
140	;
141
142	re : e EQ e
143	= bundle(3, $1, $3, "=" );
144	\| e '<' e
145	= bundle(3, $1, $3, ">" );
146	\| e '>' e
147	= bundle(3, $1, $3, "<" );
148	\| e NE e
149	= bundle(3, $1, $3, "!=" );
150	\| e GE e
151	= bundle(3, $1, $3, "!>" );
152	\| e LE e
153	= bundle(3, $1, $3, "!<" );
154	\| e
155	= bundle(2, $1, " 0!=" );
156	;
157
158	e : e '+' e
159	= bundle(3, $1, $3, "+" );
160	\| e '-' e
161	= bundle(3, $1, $3, "-" );
162	\| '-' e %prec UMINUS
163	= bundle(3, " 0", $2, "-" );
164	\| e '*' e
165	= bundle(3, $1, $3, "*" );
166	\| e '/' e
167	= bundle(3, $1, $3, "/" );
168	\| e '%' e
169	= bundle(3, $1, $3, "%%" );
170	\| e '^' e
171	= bundle(3, $1, $3, "^" );
172	\| LETTER '[' e ']'
173	={ bundle(3,$3, ";", geta($1)); }
174	\| LETTER INCR
175	= bundle(4, "l", $1, "d1+s", $1 );
176	\| INCR LETTER
177	= bundle(4, "l", $2, "1+ds", $2 );
178	\| DECR LETTER
179	= bundle(4, "l", $2, "1-ds", $2 );
180	\| LETTER DECR
181	= bundle(4, "l", $1, "d1-s", $1 );
182	\| LETTER '[' e ']' INCR
183	= bundle(7,$3,";",geta($1),"d1+",$3,":",geta($1));
184	\| INCR LETTER '[' e ']'
185	= bundle(7,$4,";",geta($2),"1+d",$4,":",geta($2));
186	\| LETTER '[' e ']' DECR
187	= bundle(7,$3,";",geta($1),"d1-",$3,":",geta($1));
188	\| DECR LETTER '[' e ']'
189	= bundle(7,$4,";",geta($2),"1-d",$4,":",geta($2));
190	\| SCALE INCR
191	= bundle(1,"Kd1+k");
192	\| INCR SCALE
193	= bundle(1,"K1+dk");
194	\| SCALE DECR
195	= bundle(1,"Kd1-k");
196	\| DECR SCALE
197	= bundle(1,"K1-dk");
198	\| BASE INCR
199	= bundle(1,"Id1+i");
200	\| INCR BASE
201	= bundle(1,"I1+di");
202	\| BASE DECR
203	= bundle(1,"Id1-i");
204	\| DECR BASE
205	= bundle(1,"I1-di");
206	\| OBASE INCR
207	= bundle(1,"Od1+o");
208	\| INCR OBASE
209	= bundle(1,"O1+do");
210	\| OBASE DECR
211	= bundle(1,"Od1-o");
212	\| DECR OBASE
213	= bundle(1,"O1-do");
214	\| LETTER '(' cargs ')'
215	= bundle(4, $3, "l", getf($1), "x" );
216	\| LETTER '(' ')'
217	= bundle(3, "l", getf($1), "x" );
218	\| cons
219	={ bundle(2, " ", $1 ); }
220	\| DOT cons
221	={ bundle(2, " .", $2 ); }
222	\| cons DOT cons
223	={ bundle(4, " ", $1, ".", $3 ); }
224	\| cons DOT
225	={ bundle(3, " ", $1, "." ); }
226	\| DOT
227	={ $$ = "l."; }
228	\| LETTER
229	= { bundle(2, "l", $1 ); }
230	\| LETTER '=' e
231	={ bundle(3, $3, "ds", $1 ); }
232	\| LETTER EQOP e %prec '='
233	={ bundle(6, "l", $1, $3, $2, "ds", $1 ); }
234	\| LETTER '[' e ']' '=' e
235	= { bundle(5,$6,"d",$3,":",geta($1)); }
236	\| LETTER '[' e ']' EQOP e
237	= { bundle(9,$3,";",geta($1),$6,$5,"d",$3,":",geta($1)); }
238	\| LENGTH '(' e ')'
239	= bundle(2,$3,"Z");
240	\| SCALE '(' e ')'
241	= bundle(2,$3,"X"); /* must be before '(' e ')' */
242	\| '(' e ')'
243	= { $$ = $2; }
244	\| '?'
245	={ bundle(1, "?" ); }
246	\| SQRT '(' e ')'
247	={ bundle(2, $3, "v" ); }
248	\| '~' LETTER
249	={ bundle(2,"L",$2); }
250	\| SCALE '=' e
251	= bundle(2,$3,"dk");
252	\| SCALE EQOP e %prec '='
253	= bundle(4,"K",$3,$2,"dk");
254	\| BASE '=' e
255	= bundle(2,$3,"di");
256	\| BASE EQOP e %prec '='
257	= bundle(4,"I",$3,$2,"di");
258	\| OBASE '=' e
259	= bundle(2,$3,"do");
260	\| OBASE EQOP e %prec '='
261	= bundle(4,"O",$3,$2,"do");
262	\| SCALE
263	= bundle(1,"K");
264	\| BASE
265	= bundle(1,"I");
266	\| OBASE
267	= bundle(1,"O");
268	;
269
270	cargs : eora
271	\| cargs ',' eora
272	= bundle(2, $1, $3 );
273	;
274	eora: e
275	\| LETTER '[' ']'
276	=bundle(2,"l",geta($1));
277	;
278
279	cons : constant
280	={ *cp++ = '\0'; }
281
282	constant:
283	'_'
284	={ $$ = cp; *cp++ = '_'; }
285	\| DIGIT
286	={ $$ = cp; *cp++ = $1; }
287	\| constant DIGIT
288	={ *cp++ = $2; }
289	;
290
291	CRS :
292	={ $$ = cp; cp++ = crs++; cp++ = '\0';
293	if(crs == '[')crs=+3;
294	if(crs == 'a')crs='{';
295	if(crs >= 0241){yyerror("program too big");
296	getout();
297	}
298	bstack[bindx++] = lev++; }
299	;
300
301	def : _DEFINE LETTER '('
302	={ $$ = getf($2);
303	pre = "";
304	post = "";
305	lev = 1;
306	bstack[bindx=0] = 0;
307	}
308	;
309
310	dargs :
311	\| lora
312	={ pp( $1 ); }
313	\| dargs ',' lora
314	={ pp( $3 ); }
315	;
316
317	dlets : lora
318	={ tp($1); }
319	\| dlets ',' lora
320	={ tp($3); }
321	;
322	lora : LETTER
323	\| LETTER '[' ']'
324	={ $$ = geta($1); }
325	;
326
327	%%
328	# define error 256
329
330	int peekc = -1;
331	int sargc;
332	int ifile;
333	char **sargv;
334
335	char funtab[52] = {
336	01,0,02,0,03,0,04,0,05,0,06,0,07,0,010,0,011,0,012,0,013,0,014,0,015,0,016,0,017,0,
337	020,0,021,0,022,0,023,0,024,0,025,0,026,0,027,0,030,0,031,0,032,0 };
338	char atab[52] = {
339	0241,0,0242,0,0243,0,0244,0,0245,0,0246,0,0247,0,0250,0,0251,0,0252,0,0253,0,
340	0254,0,0255,0,0256,0,0257,0,0260,0,0261,0,0262,0,0263,0,0264,0,0265,0,0266,0,
341	0267,0,0270,0,0271,0,0272,0};
342	char *letr[26] = {
343	"a","b","c","d","e","f","g","h","i","j",
344	"k","l","m","n","o","p","q","r","s","t",
345	"u","v","w","x","y","z" } ;
346	char *dot = { "." };
347	yylex(){
348	int c, ch;
349	restart:
350	c = getch();
351	peekc = -1;
352	while( c == ' ' \|\| c == '\t' ) c = getch();
353	if(c == '\\'){
354	getch();
355	goto restart;
356	}
357	if( c<= 'z' && c >= 'a' ) {
358	/* look ahead to look for reserved words */
359	peekc = getch();
360	if( peekc >= 'a' && peekc <= 'z' ){ /* must be reserved word */
361	if( c=='i' && peekc=='f' ){ c=_IF; goto skip; }
362	if( c=='w' && peekc=='h' ){ c=_WHILE; goto skip; }
363	if( c=='f' && peekc=='o' ){ c=_FOR; goto skip; }
364	if( c=='s' && peekc=='q' ){ c=SQRT; goto skip; }
365	if( c=='r' && peekc=='e' ){ c=_RETURN; goto skip; }
366	if( c=='b' && peekc=='r' ){ c=_BREAK; goto skip; }
367	if( c=='d' && peekc=='e' ){ c=_DEFINE; goto skip; }
368	if( c=='s' && peekc=='c' ){ c= SCALE; goto skip; }
369	if( c=='b' && peekc=='a' ){ c=BASE; goto skip; }
370	if( c=='i' && peekc == 'b'){ c=BASE; goto skip; }
371	if( c=='o' && peekc=='b' ){ c=OBASE; goto skip; }
372	if( c=='d' && peekc=='i' ){ c=FFF; goto skip; }
373	if( c=='a' && peekc=='u' ){ c=_AUTO; goto skip; }
374	if( c == 'l' && peekc=='e'){ c=LENGTH; goto skip; }
375	if( c == 'q' && peekc == 'u'){getout();}
376	/* could not be found */
377	return( error );
378	skip: /* skip over rest of word */
379	peekc = -1;
380	while( (ch = getch()) >= 'a' && ch <= 'z' );
381	peekc = ch;
382	return( c );
383	}
384
385	/* usual case; just one single letter */
386
387	yylval = letr[c-'a'];
388	return( LETTER );
389	}
390	if( c>= '0' && c <= '9' \|\| c>= 'A' && c<= 'F' ){
391	yylval = c;
392	return( DIGIT );
393	}
394	switch( c ){
395	case '.': return( DOT );
396	case '=':
397	switch( peekc = getch() ){
398	case '=': c=EQ; goto gotit;
399	case '+': c=EQPL; goto gotit;
400	case '-': c=EQMI; goto gotit;
401	case '*': c=EQMUL; goto gotit;
402	case '/': c=EQDIV; goto gotit;
403	case '%': c=EQREM; goto gotit;
404	case '^': c=EQEXP; goto gotit;
405	default: return( '=' );
406	gotit: peekc = -1; return(c);
407	}
408	case '+': return( cpeek( '+', INCR, '+' ) );
409	case '-': return( cpeek( '-', DECR, '-' ) );
410	case '<': return( cpeek( '=', LE, '<' ) );
411	case '>': return( cpeek( '=', GE, '>' ) );
412	case '!': return( cpeek( '=', NE, '!' ) );
413	case '/':
414	if((peekc = getch()) == '*'){
415	peekc = -1;
416	while((getch() != '*') \|\| ((peekc = getch()) != '/'));
417	peekc = -1;
418	goto restart;
419	}
420	else return(c);
421	case '"':
422	yylval = str;
423	while((c=getch()) != '"'){*str++ = c;
424	if(str >= &string[999]){yyerror("string space exceeded");
425	getout();
426	}
427	}
428	*str++ = '\0';
429	return(QSTR);
430	default: return( c );
431	}
432	}
433
434	cpeek( c, yes, no ){
435	if( (peekc=getch()) != c ) return( no );
436	else {
437	peekc = -1;
438	return( yes );
439	}
440	}
441
442	getch(){
443	int ch;
444	loop:
445	ch = (peekc < 0) ? getc(in) : peekc;
446	peekc = -1;
447	if(ch != EOF)return(ch);
448	if(++ifile > sargc){
449	if(ifile >= sargc+2)getout();
450	in = stdin;
451	ln = 0;
452	goto loop;
453	}
454	fclose(in);
455	if((in = fopen(sargv[ifile],"r")) != NULL){
456	ln = 0;
457	ss = sargv[ifile];
458	goto loop;
459	}
460	yyerror("cannot open input file");
461	}
462	# define b_sp_max 3000
463	int b_space [ b_sp_max ];
464	int * b_sp_nxt = { b_space };
465
466	int bdebug = 0;
467	bundle(a){
468	int i, p, q;
469
470	p = &a;
471	i = *p++;
472	q = b_sp_nxt;
473	if( bdebug ) printf("bundle %d elements at %o\n",i, q );
474	while(i-- > 0){
475	if( b_sp_nxt >= & b_space[b_sp_max] ) yyerror( "bundling space exceeded" );
476	* b_sp_nxt++ = *p++;
477	}
478	* b_sp_nxt++ = 0;
479	yyval = q;
480	return( q );
481	}
482
483	routput(p) int *p; {
484	if( bdebug ) printf("routput(%o)\n", p );
485	if( p >= &b_space[0] && p < &b_space[b_sp_max]){
486	/* part of a bundle */
487	while( p != 0 ) routput( p++ );
488	}
489	else printf( p ); /* character string */
490	}
491
492	output( p ) int *p; {
493	routput( p );
494	b_sp_nxt = & b_space[0];
495	printf( "\n" );
496	fflush(stdout);
497	cp = cary;
498	crs = rcrs;
499	}
500
501	conout( p, s ) int p; char s; {
502	printf("[");
503	routput( p );
504	printf("]s%s\n", s );
505	fflush(stdout);
506	lev--;
507	}
508
509	yyerror( s ) char *s; {
510	if(ifile > sargc)ss="teletype";
511	printf("c[%s on line %d, %s]pc\n", s ,ln+1,ss);
512	fflush(stdout);
513	cp = cary;
514	crs = rcrs;
515	bindx = 0;
516	lev = 0;
517	b_sp_nxt = &b_space[0];
518	}
519
520	pp( s ) char *s; {
521	/* puts the relevant stuff on pre and post for the letter s */
522
523	bundle(3, "S", s, pre );
524	pre = yyval;
525	bundle(4, post, "L", s, "s." );
526	post = yyval;
527	}
528
529	tp( s ) char s; { / same as pp, but for temps */
530	bundle(3, "0S", s, pre );
531	pre = yyval;
532	bundle(4, post, "L", s, "s." );
533	post = yyval;
534	}
535
536	yyinit(argc,argv) int argc; char *argv[];{
537	signal( 2, (int()())1 ); / ignore all interrupts */
538	sargv=argv;
539	sargc= -- argc;
540	if(sargc == 0)in=stdin;
541	else if((in = fopen(sargv[1],"r")) == NULL)
542	yyerror("cannot open input file");
543	ifile = 1;
544	ln = 0;
545	ss = sargv[1];
546	}
547	int *getout(){
548	printf("q");
549	fflush(stdout);
550	exit();
551	}
552
553	int *
554	getf(p) char *p;{
555	return(&funtab[2(p -0141)]);
556	}
557	int *
558	geta(p) char *p;{
559	return(&atab[2(p - 0141)]);
560	}
561
562	main(argc, argv)
563	char **argv;
564	{
565	int p[2];
566
567
568	if (argc > 1 && *argv[1] == '-') {
569	if((argv[1][1] == 'd')\|\|(argv[1][1] == 'c')){
570	yyinit(--argc, ++argv);
571	yyparse();
572	exit();
573	}
574	if(argv[1][1] != 'l'){
575	printf("unrecognizable argument\n");
576	fflush(stdout);
577	exit();
578	}
579	argv[1] = "/usr/lib/lib.b";
580	}
581	pipe(p);
582	if (fork()==0) {
583	close(1);
584	dup(p[1]);
585	close(p[0]);
586	close(p[1]);
587	yyinit(argc, argv);
588	yyparse();
589	exit();
590	}
591	close(0);
592	dup(p[0]);
593	close(p[0]);
594	close(p[1]);
595	execl("/bin/dc", "dc", "-", 0);
596	execl("/usr/bin/dc", "dc", "-", 0);
597	}