incubator-nuttx/libc/stdlib/lib_itoa.c

86 lines
3.0 KiB
C

/****************************************************************************
* libc/stdlib/lib_itoa.c
*
* Copyright (C) 2013 Brooks Automation, Inc. All rights reserved.
* Author: Ryan Sundberg <ryan.sundberg@brooks.com>
*
* This file is a part of NuttX:
*
* Copyright (C) 2010-2011 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 <stdlib.h>
/****************************************************************************
* Public Functions
****************************************************************************/
FAR char *itoa(int val, FAR char *str, int base)
{
static FAR const char *digits = "0123456789abcdefghijklmnopqrstuvwxyz";
int intval = abs(val), digit, pos, len;
FAR char *buf = str;
char swap;
if (base >= 2 && base <= 36)
{
do
{
digit = intval % base;
intval = intval / base;
*buf++ = digits[digit];
}
while (intval > 0);
if (val < 0)
{
*buf++ = '-';
}
for (pos = 0, len = buf - str; pos < len / 2; pos++)
{
swap = str[len - pos - 1];
str[len - pos - 1] = str[pos];
str[pos] = swap;
}
}
*buf = '\0';
return str;
}