_strtoul.c

test file nucleus source

/*************************************************************************
*
*               Copyright Mentor Graphics Corporation 2002
*                         All Rights Reserved.
*
* THIS WORK CONTAINS TRADE SECRET AND PROPRIETARY INFORMATION WHICH IS
* THE PROPERTY OF MENTOR GRAPHICS CORPORATION OR ITS LICENSORS AND IS
* SUBJECT TO LICENSE TERMS.
*
*************************************************************************/

/*************************************************************************
* FILE NAME                                     VERSION
*
*       _strtoul.c                              Nucleus Common Library 1.1
*
* DESCRIPTION
*
*       This file contains the implementation of NCL__strtoul.
*
* DATA STRUCTURES
*
*       None.
*
* FUNCTIONS
*
*       NCL__strtoul
*
* DEPENDENCIES
*
*       ncl.h
*       abbr.h
*       errno.h
*       convert.h
*       nucleus.h
*
************************************************************************/

#define NU_NCL_SOURCE_FILE

#include "ncl\inc\ncl.h"
#include "ncl\inc\abbr.h"                                    /* rcchar */
#include "ncl\inc\errno.h"
#include "ncl\inc\convert.h"
#include "plus\nucleus.h"                                /* MMU Support */

/*************************************************************************
*
*   FUNCTION
*
*       NCL__strtoul
*
*   DESCRIPTION
*
*       The routine is used to scan a single unsigned long integer from
*       at most 'width' characters in a string.  If 'width' is negative,
*       there is no limit to the number of characters scanned.  The
*       integer may be preceeded by an optional sign character, but
*       whitespace characters are invalid.  The 'max' value determines
*       the largest value which will not cause overflow.  If the converted
*       value exceeds 'max', errno will be set to ERANGE and 'max' will be
*       returned.  In other respects, it acts like "strtoul".
*
*   INPUTS
*
*       nptr                Null-terminated string to converts
*       base                Number system (binary, hex, octal, etc...)
*       width               Maximum # of chars to scan (-1 = unlimited)
*       max                 Largest value that will not cause an overflow
*
*   OUTPUTS
*
*       ulong               Value the string represents
*
*************************************************************************/

ulong NCL__strtoul(const char *nptr, char **endptr, int base, int width,
                    ulong max)
{
    rcchar *ptr = nptr;
    ulong  uvalue;
    int    neg = 0;
    char *eptr;
    NU_SUPERV_USER_VARIABLES

    if (*ptr == '-')                               /* get optional sign */
    {
        neg = 1;
        goto do_sign;
    }
    if (*ptr == '+')
    {
        do_sign:
        if (width == 0)
        {
            eptr = (char *)nptr;
            uvalue = 0L;
            goto exit;
        }
        if (width > 0)
            --width;
        ++ptr;
    }

    switch (NCL__str2ul (&uvalue, ptr, &eptr, width, base))
    {
        case S2L_ERROR:
            uvalue = 0L;
            eptr = (char *)nptr;
            if (width && *ptr == '0')               /* "0x?" is valid */
                eptr = (char *)(ptr + 1);
            break;

        case S2L_VALID:
            if (uvalue > max)
                goto overflow;         /* check for overflow */
            if (neg)
                uvalue = -uvalue;
            break;

        case S2L_OVFLW:
            overflow:
            uvalue = max;
            NU_SUPERVISOR_MODE();
            errno = ERANGE;
            NU_USER_MODE();
            break;
    }

exit:
    if (endptr)
        *endptr = eptr;

    return (uvalue);
}