freebsd-src/usr.bin/window/parser3.c
1994-05-27 12:33:43 +00:00

192 lines
4.2 KiB
C

/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
static char sccsid[] = "@(#)parser3.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#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*/
}