mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-21 04:31:04 +08:00
80 lines
1.8 KiB
C
80 lines
1.8 KiB
C
/* Copyright (C) 1995-2017 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <wchar.h>
|
|
|
|
#ifndef WCSNCAT
|
|
# define WCSNCAT wcsncat
|
|
#endif
|
|
|
|
/* Append no more than N wide-character of SRC onto DEST. */
|
|
wchar_t *
|
|
WCSNCAT (wchar_t *dest, const wchar_t *src, size_t n)
|
|
{
|
|
wchar_t c;
|
|
wchar_t * const s = dest;
|
|
|
|
/* Find the end of DEST. */
|
|
do
|
|
c = *dest++;
|
|
while (c != L'\0');
|
|
|
|
/* Make DEST point before next character, so we can increment
|
|
it while memory is read (wins on pipelined cpus). */
|
|
dest -= 2;
|
|
|
|
if (n >= 4)
|
|
{
|
|
size_t n4 = n >> 2;
|
|
do
|
|
{
|
|
c = *src++;
|
|
*++dest = c;
|
|
if (c == L'\0')
|
|
return s;
|
|
c = *src++;
|
|
*++dest = c;
|
|
if (c == L'\0')
|
|
return s;
|
|
c = *src++;
|
|
*++dest = c;
|
|
if (c == L'\0')
|
|
return s;
|
|
c = *src++;
|
|
*++dest = c;
|
|
if (c == L'\0')
|
|
return s;
|
|
} while (--n4 > 0);
|
|
n &= 3;
|
|
}
|
|
|
|
while (n > 0)
|
|
{
|
|
c = *src++;
|
|
*++dest = c;
|
|
if (c == L'\0')
|
|
return s;
|
|
n--;
|
|
}
|
|
|
|
if (c != L'\0')
|
|
*++dest = L'\0';
|
|
|
|
return s;
|
|
}
|