octtoint.c revision 1.2 
1/*	$NetBSD: octtoint.c,v 1.2 2009/12/14 00:38:48 christos Exp $	*/
2
3/*
4 * octtoint - convert an ascii string in octal to an unsigned
5 *	      long, with error checking
6 */
7#include <stdio.h>
8#include <ctype.h>
9
10#include "ntp_stdlib.h"
11
12int
13octtoint(
14	const char *str,
15	u_long *ival
16	)
17{
18	register u_long u;
19	register const char *cp;
20
21	cp = str;
22
23	if (*cp == '\0')
24	    return 0;
25
26	u = 0;
27	while (*cp != '\0') {
28		if (!isdigit((unsigned char)*cp) || *cp == '8' || *cp == '9')
29		    return 0;
30		if (u >= 0x20000000)
31		    return 0;	/* overflow */
32		u <<= 3;
33		u += *cp++ - '0';	/* ascii dependent */
34	}
35	*ival = u;
36	return 1;
37}
38