incubator-nuttx/libs/libc/stdio/lib_ultoa_invert.c

85 lines
2.7 KiB
C

/****************************************************************************
* libs/libc/stdio/lib_ultoa_invert.c
*
* Copyright © 2017, Keith Packard
* All rights reserved.
*
* 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 "lib_ultoa_invert.h"
/****************************************************************************
* Public Functions
****************************************************************************/
#ifdef CONFIG_LIBC_LONG_LONG
FAR char *__ultoa_invert(unsigned long long val, FAR char *str, int base)
#else
FAR char *__ultoa_invert(unsigned long val, FAR char *str, int base)
#endif
{
int upper = 0;
if (base & XTOA_UPPER)
{
upper = 1;
base &= ~XTOA_UPPER;
}
do
{
int v;
v = val % base;
val = val / base;
if (v <= 9)
{
v += '0';
}
else
{
if (upper)
v += 'A' - 10;
else
v += 'a' - 10;
}
*str++ = v;
}
while (val);
return str;
}