154359Sroberto/*
254359Sroberto * atouint - convert an ascii string to an unsigned long, with error checking
354359Sroberto */
454359Sroberto#include <sys/types.h>
554359Sroberto#include <ctype.h>
654359Sroberto
754359Sroberto#include "ntp_types.h"
854359Sroberto#include "ntp_stdlib.h"
954359Sroberto
1054359Srobertoint
1154359Srobertoatouint(
1254359Sroberto	const char *str,
1354359Sroberto	u_long *uval
1454359Sroberto	)
1554359Sroberto{
1654359Sroberto	register u_long u;
1754359Sroberto	register const char *cp;
1854359Sroberto
1954359Sroberto	cp = str;
2054359Sroberto	if (*cp == '\0')
2154359Sroberto	    return 0;
2254359Sroberto
2354359Sroberto	u = 0;
2454359Sroberto	while (*cp != '\0') {
2554359Sroberto		if (!isdigit((int)*cp))
2654359Sroberto		    return 0;
2754359Sroberto		if (u > 429496729 || (u == 429496729 && *cp >= '6'))
2854359Sroberto		    return 0;	/* overflow */
2954359Sroberto		u = (u << 3) + (u << 1);
3054359Sroberto		u += *cp++ - '0';	/* ascii dependent */
3154359Sroberto	}
3254359Sroberto
3354359Sroberto	*uval = u;
3454359Sroberto	return 1;
3554359Sroberto}
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