/* $NetBSD: arith_token.c,v 1.7 2017/12/17 04:06:03 kre Exp $ */
/*-
* Copyright (c) 2002
* Herbert Xu.
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* 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.
*
* From FreeBSD, from dash
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: arith_token.c,v 1.7 2017/12/17 04:06:03 kre Exp $");
#endif /* not lint */
#include <inttypes.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include "shell.h"
#include "arith_tokens.h"
#include "expand.h"
#include "error.h"
#include "memalloc.h"
#include "parser.h"
#include "syntax.h"
#include "show.h"
#if ARITH_BOR + ARITH_ASS_GAP != ARITH_BORASS || \
ARITH_ASS + ARITH_ASS_GAP != ARITH_EQ
#error Arithmetic tokens are out of order.
#endif
/*
* Scan next arithmetic token, return its type,
* leave its value (when applicable) in (global) a_t_val.
*
* Input text is in (global) arith_buf which is updated to
* refer to the next char after the token returned, except
* on error (ARITH_BAD returned) where arith_buf is not altered.
*/
int
arith_token(void)
{
int token;
const char *buf = arith_buf;
char *end;
const char *p;
for (;;) {
token = *buf;
if (isdigit(token)) {
/*
* Numbers all start with a digit, and nothing
* else does, the number ends wherever
* strtoimax() stops...
*/
a_t_val.val = strtoimax(buf, &end, 0);
if (is_in_name(*end)) {
token = *end;
while (is_in_name(*++end))
continue;
error("arithmetic: unexpected '%c' "
"(out of range) in numeric constant: "
"%.*s", token, (int)(end - buf), buf);
}
arith_buf = end;
VTRACE(DBG_ARITH, ("Arith token ARITH_NUM=%jd\n",
a_t_val.val));
return ARITH_NUM;
} else if (is_name(token)) {
/*
* Variable names all start with an alpha (or '_')
* and nothing else does. They continue for the
* longest unbroken sequence of alphanumerics ( + _ )
*/
arith_var_lno = arith_lno;
p = buf;
while (buf++, is_in_name(*buf))
;
a_t_val.name = stalloc(buf - p + 1);
memcpy(a_t_val.name, p, buf - p);
a_t_val.name[buf - p] = '\0';
arith_buf = buf;
VTRACE(DBG_ARITH, ("Arith token ARITH_VAR=\"%s\"\n",
a_t_val.name));
return ARITH_VAR;
} else switch (token) {
/*
* everything else must be some kind of
* operator, white space, or an error.
*/
case '\n':
arith_lno++;
VTRACE(DBG_ARITH, ("Arith: newline\n"));
/* FALLTHROUGH */
case ' ':
case '\t':
buf++;
continue;
default:
error("arithmetic: unexpected '%c' (%#x) in expression",
token, token);
/* NOTREACHED */
case '=':
token = ARITH_ASS;
checkeq:
buf++;
checkeqcur:
if (*buf != '=')
goto out;
token += ARITH_ASS_GAP;
break;
case '>':
switch (*++buf) {
case '=':
token = ARITH_GE;
break;
case '>':
token = ARITH_RSHIFT;
goto checkeq;
default:
token = ARITH_GT;
goto out;
}
break;
case '<':
switch (*++buf) {
case '=':
token = ARITH_LE;
break;
case '<':
token = ARITH_LSHIFT;
goto checkeq;
default:
token = ARITH_LT;
goto out;
}
break;
case '|':
if (*++buf != '|') {
token = ARITH_BOR;
goto checkeqcur;
}
token = ARITH_OR;
break;
case '&':
if (*++buf != '&') {
token = ARITH_BAND;
goto checkeqcur;
}
token = ARITH_AND;
break;
case '!':
if (*++buf != '=') {
token = ARITH_NOT;
goto out;
}
token = ARITH_NE;
break;
case 0:
goto out;
case '(':
token = ARITH_LPAREN;
break;
case ')':
token = ARITH_RPAREN;
break;
case '*':
token = ARITH_MUL;
goto checkeq;
case '/':
token = ARITH_DIV;
goto checkeq;
case '%':
token = ARITH_REM;
goto checkeq;
case '+':
if (buf[1] == '+') {
buf++;
token = ARITH_INCR;
break;
}
token = ARITH_ADD;
goto checkeq;
case '-':
if (buf[1] == '-') {
buf++;
token = ARITH_DECR;
break;
}
token = ARITH_SUB;
goto checkeq;
case '~':
token = ARITH_BNOT;
break;
case '^':
token = ARITH_BXOR;
goto checkeq;
case '?':
token = ARITH_QMARK;
break;
case ':':
token = ARITH_COLON;
break;
case ',':
token = ARITH_COMMA;
break;
}
break;
}
buf++;
out:
arith_buf = buf;
VTRACE(DBG_ARITH, ("Arith token: %d\n", token));
return token;
}
