/*      @(#)parser3.c   8.1 (Berkeley) 6/6/93   */
/*      $NetBSD: parser3.c,v 1.6 2003/08/07 11:17:28 agc Exp $  */

/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Wang at The University of California, Berkeley.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "defs.h"
#include "parser.h"

/*
 * =
 * ? :
 * ||
 * &&
 * |
 * ^
 * &
 * == !=
 * <= >=
 * << >>
 * + -
 * * / %
 * unary - + ~ !
 */
int
p_expr(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);
                /* FALLTHROUGH */
        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;
}

/*
 * ? :
 */
int
p_expr0(struct value *v, char flag)
{
        struct value t;
        char true = 0;

        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;
                /* FALLTHROUGH */
        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);
}

/*
 * ||
 */
int
p_expr1(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;
                        /* FALLTHROUGH */
                case V_ERR:
                        flag = 0;
                        break;
                }
                if (token != T_OROR)
                        return 0;
                (void) s_gettok();
                if (p_expr2(v, flag && !true) < 0)
                        return -1;
        }
}

/*
 * &&
 */
int
p_expr2(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;
                        /* FALLTHROUGH */
                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*/
}