add pathnames.h
[unix-history] / usr / src / usr.bin / window / parser1.c
/*
* Copyright (c) 1983 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifndef lint
static char sccsid[] = "@(#)parser1.c 3.20 (Berkeley) %G%";
#endif /* not lint */
#include "parser.h"
p_start()
{
char flag = 1;
(void) s_gettok();
for (;;) {
p_statementlist(flag);
if (token == T_EOF || p_abort())
break;
flag = 0;
p_synerror();
while (token != T_EOL && token != T_EOF) {
if (token == T_STR)
str_free(token_str);
(void) s_gettok();
}
if (token == T_EOL)
(void) s_gettok();
p_clearerr();
}
}
p_statementlist(flag)
char flag;
{
for (; p_statement(flag) >= 0; p_clearerr())
;
}
p_statement(flag)
char flag;
{
switch (token) {
case T_EOL:
(void) s_gettok();
return 0;
case T_IF:
return p_if(flag);
default:
return p_expression(flag);
}
}
p_if(flag)
char flag;
{
struct value t;
char true = 0;
top:
(void) s_gettok();
if (p_expr(&t, flag) < 0) {
p_synerror();
return -1;
}
switch (t.v_type) {
case V_NUM:
true = !true && t.v_num != 0;
break;
case V_STR:
p_error("if: Numeric value required.");
str_free(t.v_str);
case V_ERR:
flag = 0;
break;
}
if (token != T_THEN) {
p_synerror();
return -1;
}
(void) s_gettok();
p_statementlist(flag && true);
if (p_erred())
return -1;
if (token == T_ELSIF)
goto top;
if (token == T_ELSE) {
(void) s_gettok();
p_statementlist(flag && !true);
if (p_erred())
return -1;
}
if (token == T_ENDIF) {
(void) s_gettok();
return 0;
}
p_synerror();
return -1;
}
p_expression(flag)
char flag;
{
struct value t;
char *cmd;
int p_function(), p_assign();
switch (token) {
case T_NUM:
t.v_type = V_NUM;
t.v_num = token_num;
(void) s_gettok();
break;
case T_STR:
t.v_type = V_STR;
t.v_str = token_str;
(void) s_gettok();
break;
default:
if (p_expr(&t, flag) < 0)
return -1;
if (token == T_EOF) {
val_free(t);
return 0;
}
}
if (token != T_ASSIGN && p_convstr(&t) < 0)
return -1;
cmd = t.v_type == V_STR ? t.v_str : 0;
if ((*(token == T_ASSIGN ? p_assign : p_function))(cmd, &t, flag) < 0) {
if (cmd)
str_free(cmd);
return -1;
}
if (cmd)
str_free(cmd);
val_free(t);
if (token == T_EOL)
(void) s_gettok();
else if (token != T_EOF) {
p_synerror();
return -1;
}
return 0;
}
p_convstr(v)
register struct value *v;
{
if (v->v_type != V_NUM)
return 0;
if ((v->v_str = str_itoa(v->v_num)) == 0) {
p_memerror();
v->v_type = V_ERR;
return -1;
}
v->v_type = V_STR;
return 0;
}
p_synerror()
{
if (!cx.x_synerred) {
cx.x_synerred = cx.x_erred = 1;
error("Syntax error.");
}
}
/*VARARGS1*/
p_error(msg, a, b, c)
char *msg;
{
if (!cx.x_erred) {
cx.x_erred = 1;
error(msg, a, b, c);
}
}
p_memerror()
{
cx.x_erred = cx.x_abort = 1;
error("Out of memory.");
}