incubator-nuttx/libs/libc/wchar/lib_wcsncpy.c

70 lines
2.6 KiB
C

/****************************************************************************
* libs/libc/wchar/lib_wcsncpy.c
*
* Copyright © 2005-2014 Rich Felker, et al.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <wchar.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: wcsncpy
*
* Description:
* Copies the first num characters of source to destination. If the end
* of the source C wide string (which is signaled by a null wide
* character) is found before num characters have been copied, destination
* is padded with additional null wide characters until a total of num
* characters have been written to it.
*
* Input Parameters:
* d - the destination wchar string where the content is to be copied
* s - the wchar string to be copied
* n - maximum number of wide characters to be copied from source
*
* Returned Value:
* A pointer to the destination string
*
****************************************************************************/
FAR wchar_t *wcsncpy(FAR wchar_t *d, FAR const wchar_t *s, size_t n)
{
FAR wchar_t *a = d;
while (n && *s)
{
*d++ = *s++;
n--;
}
wmemset(d, 0, n);
return a;
}