root/usr/src/lib/libc/port/gen/atoll.c
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */

#include "lint.h"
#include <ctype.h>
#include <sys/types.h>
#include <stdlib.h>

#define ATOLL

#if defined     ATOI
typedef int TYPE;
#define NAME    atoi
#elif defined ATOL
typedef long TYPE;
#define NAME    atol
#else
typedef longlong_t TYPE;
#define NAME    atoll
#endif

TYPE
NAME(const char *p)
{
        TYPE n;
        int c, neg = 0;
        unsigned char   *up = (unsigned char *)p;

        if (!isdigit(c = *up)) {
                while (isspace(c))
                        c = *++up;
                switch (c) {
                case '-':
                        neg++;
                        /* FALLTHROUGH */
                case '+':
                        c = *++up;
                }
                if (!isdigit(c))
                        return (0);
        }
        for (n = '0' - c; isdigit(c = *++up); ) {
                n *= 10; /* two steps to avoid unnecessary overflow */
                n += '0' - c; /* accum neg to avoid surprises at MAX */
        }
        return (neg ? n : -n);
}