[unix-history] / usr / src / usr.bin / window / parser3.c

#ifndef lint
static char sccsid[] = "@(#)parser3.c	3.5 %G%";
#endif

/*
 * Copyright (c) 1983 Regents of the University of California,
 * All rights reserved.  Redistribution permitted subject to
 * the terms of the Berkeley Software License Agreement.
 */

#include "parser.h"

/*
 * =
 * ? :
 * ||
 * &&
 * |
 * ^
 * &
 * == !=
 * <= >=
 * << >>
 * + -
 * * / %
 * unary - + ~ !
 */
p_expr(v, flag)
register struct value *v;
char flag;
{
	struct value t;
	int ret;

	if (p_expr0(&t, flag) < 0)
		return -1;

	if (token != T_ASSIGN) {
		*v = t;
		return 0;
	}
	switch (t.v_type) {
	case V_NUM:
		p_error("%d: Not a variable.", t.v_num);
	case V_ERR:
		t.v_str = 0;
		break;
	}
	ret = p_assign(t.v_str, v, flag);
	if (t.v_str != 0)
		str_free(t.v_str);
	return ret;
}

/*
 * ? :
 */
p_expr0(v, flag)
register struct value *v;
char flag;
{
	struct value t;
	char true;

	if (p_expr1(v, flag) < 0)
		return -1;
	if (token != T_QUEST)
		return 0;
	switch (v->v_type) {
	case V_NUM:
		true = v->v_num != 0;
		break;
	case V_STR:
		p_error("?: Numeric left operand required.");
		str_free(v->v_str);
		v->v_type = V_ERR;
	case V_ERR:
		flag = 0;
		break;
	}
	(void) s_gettok();
	v->v_type = V_ERR;
	if ((flag && true ? p_expr1(v, 1) : p_expr1(&t, 0)) < 0)
		return -1;
	if (token != T_COLON) {
		val_free(*v);
		p_synerror();
		return -1;
	}
	(void) s_gettok();
	return flag && !true ? p_expr1(v, 1) : p_expr1(&t, 0);
}

/*
 * ||
 */
p_expr1(v, flag)
register struct value *v;
char flag;
{
	char true = 0;

	if (p_expr2(v, flag) < 0)
		return -1;
	if (token != T_OROR)
		return 0;
	for (;;) {
		switch (v->v_type) {
		case V_NUM:
			v->v_num = true = true || v->v_num != 0;
			break;
		case V_STR:
			p_error("||: Numeric operands required.");
			str_free(v->v_str);
			v->v_type = V_ERR;
		case V_ERR:
			flag = 0;
			break;
		}
		if (token != T_OROR)
			return 0;
		(void) s_gettok();
		if (p_expr2(v, flag && !true) < 0)
			return -1;
	}
}

/*
 * &&
 */
p_expr2(v, flag)
register struct value *v;
char flag;
{
	char true = 1;

	if (p_expr3_10(3, v, flag) < 0)
		return -1;
	if (token != T_ANDAND)
		return 0;
	for (;;) {
		switch (v->v_type) {
		case V_NUM:
			v->v_num = true = true && v->v_num != 0;
			break;
		case V_STR:
			p_error("&&: Numeric operands required.");
			str_free(v->v_str);
			v->v_type = V_ERR;
		case V_ERR:
			flag = 0;
			break;
		}
		if (token != T_ANDAND)
			return 0;
		(void) s_gettok();
		if (p_expr3_10(3, v, flag && true) < 0)
			return -1;
	}
	/*NOTREACHED*/
}
Commit	Line	Data
6c6eaf9a	1	#ifndef lint
60de5df9	2	static char sccsid[] = "@(#)parser3.c 3.5 %G%";
6c6eaf9a EW	3	#endif
6c6eaf9a EW	4
60de5df9 EW	5	/*
	6	* Copyright (c) 1983 Regents of the University of California,
	7	* All rights reserved. Redistribution permitted subject to
	8	* the terms of the Berkeley Software License Agreement.
	9	*/
	10
6c6eaf9a EW	11	#include "parser.h"
	12
	13	/*
	14	* =
	15	* ? :
	16	* \|\|
	17	* &&
	18	* \|
	19	* ^
	20	* &
	21	* == !=
	22	* <= >=
	23	* << >>
	24	* + -
	25	* * / %
	26	* unary - + ~ !
	27	*/
	28	p_expr(v, flag)
	29	register struct value *v;
	30	char flag;
	31	{
	32	struct value t;
	33	int ret;
	34
6c6eaf9a EW	35	if (p_expr0(&t, flag) < 0)
	36	return -1;
	37
	38	if (token != T_ASSIGN) {
	39	*v = t;
	40	return 0;
	41	}
	42	switch (t.v_type) {
bb4a0c0b EW	43	case V_NUM:
bb4a0c0b EW	44	p_error("%d: Not a variable.", t.v_num);
6c6eaf9a EW	45	case V_ERR:
	46	t.v_str = 0;
	47	break;
6c6eaf9a EW	48	}
	49	ret = p_assign(t.v_str, v, flag);
	50	if (t.v_str != 0)
	51	str_free(t.v_str);
	52	return ret;
	53	}
	54
	55	/*
	56	* ? :
	57	*/
	58	p_expr0(v, flag)
	59	register struct value *v;
	60	char flag;
	61	{
	62	struct value t;
	63	char true;
	64
	65	if (p_expr1(v, flag) < 0)
	66	return -1;
	67	if (token != T_QUEST)
	68	return 0;
	69	switch (v->v_type) {
	70	case V_NUM:
	71	true = v->v_num != 0;
	72	break;
	73	case V_STR:
fbbe9777	74	p_error("?: Numeric left operand required.");
6c6eaf9a EW	75	str_free(v->v_str);
	76	v->v_type = V_ERR;
	77	case V_ERR:
	78	flag = 0;
	79	break;
	80	}
	81	(void) s_gettok();
	82	v->v_type = V_ERR;
	83	if ((flag && true ? p_expr1(v, 1) : p_expr1(&t, 0)) < 0)
	84	return -1;
	85	if (token != T_COLON) {
	86	val_free(*v);
	87	p_synerror();
	88	return -1;
	89	}
	90	(void) s_gettok();
	91	return flag && !true ? p_expr1(v, 1) : p_expr1(&t, 0);
	92	}
	93
	94	/*
	95	* \|\|
	96	*/
	97	p_expr1(v, flag)
	98	register struct value *v;
	99	char flag;
	100	{
	101	char true = 0;
	102
	103	if (p_expr2(v, flag) < 0)
	104	return -1;
	105	if (token != T_OROR)
	106	return 0;
	107	for (;;) {
	108	switch (v->v_type) {
	109	case V_NUM:
	110	v->v_num = true = true \|\| v->v_num != 0;
	111	break;
	112	case V_STR:
fbbe9777	113	p_error("\|\|: Numeric operands required.");
6c6eaf9a EW	114	str_free(v->v_str);
	115	v->v_type = V_ERR;
	116	case V_ERR:
	117	flag = 0;
	118	break;
	119	}
	120	if (token != T_OROR)
	121	return 0;
	122	(void) s_gettok();
	123	if (p_expr2(v, flag && !true) < 0)
	124	return -1;
	125	}
	126	}
	127
	128	/*
	129	* &&
	130	*/
	131	p_expr2(v, flag)
	132	register struct value *v;
	133	char flag;
	134	{
	135	char true = 1;
	136
	137	if (p_expr3_10(3, v, flag) < 0)
	138	return -1;
	139	if (token != T_ANDAND)
	140	return 0;
	141	for (;;) {
	142	switch (v->v_type) {
	143	case V_NUM:
	144	v->v_num = true = true && v->v_num != 0;
	145	break;
	146	case V_STR:
fbbe9777	147	p_error("&&: Numeric operands required.");
6c6eaf9a EW	148	str_free(v->v_str);
	149	v->v_type = V_ERR;
	150	case V_ERR:
	151	flag = 0;
	152	break;
	153	}
	154	if (token != T_ANDAND)
	155	return 0;
	156	(void) s_gettok();
	157	if (p_expr3_10(3, v, flag && true) < 0)
	158	return -1;
	159	}
	160	/NOTREACHED/
	161	}