96 lines
3.6 KiB
C
96 lines
3.6 KiB
C
/****************************************************************************
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* libc/string/lib_memccpy.c
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*
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* Copyright (C) 2012 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <gnutt@nuttx.org>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name NuttX nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************/
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/****************************************************************************
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* Compilation Switches
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <sys/types.h>
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#include <string.h>
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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/****************************************************************************
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* Name: memccpy
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*
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* Description:
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* The memccpy() function copies bytes from memory area s2 into s1,
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* stopping after the first occurrence of byte c (converted to an unsigned
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* char) is copied, or after n bytes are copied, whichever comes first. If
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* copying takes place between objects that overlap, the behavior is
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* undefined.
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*
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* Returned Value:
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* The memccpy() function returns a pointer to the byte after the copy of c
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* in s1, or a null pointer if c was not found in the first n bytes of s2.
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*
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****************************************************************************/
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FAR void *memccpy(FAR void *s1, FAR const void *s2, int c, size_t n)
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{
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FAR unsigned char *pout = (FAR unsigned char *)s1;
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FAR unsigned char *pin = (FAR unsigned char *)s2;
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/* Copy at most n bytes */
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while (n-- > 0)
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{
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/* Copy one byte */
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*pout = *pin++;
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/* Did we just copy the terminating byte c? */
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if (*pout++ == (unsigned char)c)
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{
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/* Yes return a pointer to the byte after the copy of c into s1 */
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return (FAR void *)pout;
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}
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}
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/* C was not found in the first n bytes of s2 */
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return NULL;
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}
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