1/*	$NetBSD: atouint.c,v 1.1.1.1 2009/12/13 16:55:01 kardel Exp $	*/
2
3/*
4 * atouint - convert an ascii string to an unsigned long, with error checking
5 */
6#include <sys/types.h>
7#include <ctype.h>
8
9#include "ntp_types.h"
10#include "ntp_stdlib.h"
11
12int
13atouint(
14	const char *str,
15	u_long *uval
16	)
17{
18	register u_long u;
19	register const char *cp;
20
21	cp = str;
22	if (*cp == '\0')
23	    return 0;
24
25	u = 0;
26	while (*cp != '\0') {
27		if (!isdigit((unsigned char)*cp))
28		    return 0;
29		if (u > 429496729 || (u == 429496729 && *cp >= '6'))
30		    return 0;	/* overflow */
31		u = (u << 3) + (u << 1);
32		u += *cp++ - '0';	/* ascii dependent */
33	}
34
35	*uval = u;
36	return 1;
37}
38