/*      @(#)parser5.c   8.1 (Berkeley) 6/6/93   */
/*      $NetBSD: parser5.c,v 1.7 2009/04/14 08:50:06 lukem 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"
#include "var.h"

/*
 * unary $ $? + - ! ~
 */
int
p_expr11(struct value *v, char flag)
{
        int op;
        const char *opname;

        switch (token) {
        case T_DOLLAR:
                opname = "$";
                break;
        case T_DQ:
                opname = "$?";
                break;
        case T_PLUS:
                opname = "unary +";
                break;
        case T_MINUS:
                opname = "unary -";
                break;
        case T_NOT:
                opname = "!";
                break;
        case T_COMP:
                opname = "~";
                break;
        default:
                return p_expr12(v, flag);
        }
        op = token;
        (void) s_gettok();
        if (p_expr11(v, flag) < 0)
                return -1;
        switch (v->v_type) {
        case V_NUM:
                break;
        case V_STR:
                switch (op) {
                case T_MINUS:
                case T_NOT:
                case T_COMP:
                        p_error("%s: Numeric operand required.", opname);
                        str_free(v->v_str);
                        v->v_type = V_ERR;
                        return 0;
                }
                break;
        case V_ERR:
                return 0;
        }
        switch (op) {
        case T_DOLLAR:
        case T_DQ:
                if (v->v_type == V_NUM) {
                        int tmp = cx.x_type == X_BUF && cx.x_arg != 0 &&
                                v->v_num > 0 && v->v_num <= cx.x_narg;
                        if (op == T_DQ)
                                v->v_num = tmp;
                        else if (tmp)
                                *v = cx.x_arg[v->v_num - 1];
                        else {
                                p_error("%d: No such argument.", v->v_num);
                                v->v_type = V_ERR;
                        }
                } else {
                        char *name = v->v_str;
                        struct var *r = var_lookup(name);
                        if (op == T_DQ) {
                                v->v_type = V_NUM;
                                v->v_num = r != NULL;
                        } else if (r != NULL)
                                *v = r->r_val;
                        else {
                                p_error("%s: Undefined variable.", name);
                                v->v_type = V_ERR;
                        }
                        str_free(name);
                }
                if (v->v_type == V_STR && (v->v_str = str_cpy(v->v_str)) == 0) {
                        p_memerror();
                        return -1;
                }
                break;
        case T_MINUS:
                v->v_num = - v->v_num;
                break;
        case T_NOT:
                v->v_num = ! v->v_num;
                break;
        case T_COMP:
                v->v_num = ~ v->v_num;
                break;
        }
        return 0;
}

/*
 * string, number, ( expr )
 * Plus function calls.
 *
 * Always return v_type == V_ERR when flag == 0.
 */
int
p_expr12(struct value *v, char flag)
{
        v->v_type = V_ERR;
        switch (token) {
        case T_NUM:
                if (flag) {
                        v->v_type = V_NUM;
                        v->v_num = token_num;
                }
                (void) s_gettok();
                break;
        case T_STR:
                if (flag) {
                        v->v_type = V_STR;
                        v->v_str = token_str;
                } else
                        str_free(token_str);
                (void) s_gettok();
                break;
        case T_LP:
                (void) s_gettok();
                if (p_expr(v, flag) < 0) {
                        p_synerror();
                        return -1;
                }
                if (token != T_RP) {
                        p_synerror();
                        val_free(*v);
                        return -1;
                }
                (void) s_gettok();
                break;
        default:
                return -1;
        }
        while (token == T_LP) {
                char *cmd;

                if (p_convstr(v) < 0)
                        return -1;
                cmd = v->v_type == V_STR ? v->v_str : 0;
                if (p_function(cmd, v, flag) < 0) {
                        if (cmd)
                                str_free(cmd);
                        return -1;
                }
                if (cmd)
                        str_free(cmd);
        }
        return 0;
}