incubator-nuttx/libc/stdlib/lib_strtoull.c

123 lines
3.9 KiB
C

/****************************************************************************
* /libc/stdlib/lib_strtoull.c
*
* Copyright (C) 2009, 2010, 2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/compiler.h>
#include <stdlib.h>
#include <errno.h>
#include "libc.h"
#ifdef CONFIG_HAVE_LONG_LONG
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: strtoull
*
* Description:
* The strtoull() function converts the initial part of the string in
* nptr to a long unsigned integer value according to the given base, which
* must be between 2 and 36 inclusive, or be the special value 0.
*
* Returns:
* - The converted value, if the base and number are valid
* - 0 if an error occurs, and set errno to:
* * EINVAL if base < 2 or base > 36
* - ULLONG_MAX if an overflow occurs, and set errno to:
* * ERANGE if the number cannot be represented using unsigned long long
*
****************************************************************************/
unsigned long long strtoull(FAR const char *nptr, FAR char **endptr, int base)
{
unsigned long long accum = 0;
unsigned long long prev;
int value;
if (nptr)
{
/* Skip leading spaces */
lib_skipspace(&nptr);
/* Check for unspecified base */
base = lib_checkbase(base, &nptr);
if (base < 0)
{
set_errno(EINVAL);
return 0;
}
/* Accumulate each "digit" */
while (lib_isbasedigit(*nptr, base, &value))
{
prev = accum;
accum = accum*base + value;
nptr++;
/* Check for overflow */
if (accum < prev)
{
set_errno(ERANGE);
accum = ULLONG_MAX;
break;
}
}
/* Return the final pointer to the unused value */
if (endptr)
{
*endptr = (char *)nptr;
}
}
return accum;
}
#endif