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Diffstat (limited to 'nuttx/lib/string/lib_memccpy.c')
-rw-r--r-- | nuttx/lib/string/lib_memccpy.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/nuttx/lib/string/lib_memccpy.c b/nuttx/lib/string/lib_memccpy.c new file mode 100644 index 000000000..1f3dbb52d --- /dev/null +++ b/nuttx/lib/string/lib_memccpy.c @@ -0,0 +1,99 @@ +/**************************************************************************** + * lib/string/lib_memccpy.c + * + * Copyright (C) 2012 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. + * + ****************************************************************************/ + +/**************************************************************************** + * Compilation Switches + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#include <sys/types.h> +#include <string.h> + +/**************************************************************************** + * Global Functions + ****************************************************************************/ + + +/**************************************************************************** + * Name: memccpy + * + * Description: + * The memccpy() function copies bytes from memory area s2 into s1, + * stopping after the first occurrence of byte c (converted to an unsigned + * char) is copied, or after n bytes are copied, whichever comes first. If + * copying takes place between objects that overlap, the behavior is + * undefined. + * + * Returned Value: + * The memccpy() function returns a pointer to the byte after the copy of c + * in s1, or a null pointer if c was not found in the first n bytes of s2. + * + ****************************************************************************/ + +FAR void *memccpy(FAR void *s1, FAR const void *s2, int c, size_t n) +{ + FAR unsigned char *pout = (FAR unsigned char*)s1; + FAR unsigned char *pin = (FAR unsigned char*)s2; + + /* Copy at most n bytes */ + + while (n-- > 0) + { + /* Copy one byte */ + + *pout = *pin++; + + /* Did we just copy the terminating byte c? */ + + if (*pout == (unsigned char)c) + { + /* Yes return a pointer to the byte after the copy of c into s1 */ + + return (FAR void *)pout; + } + + /* No increment to the next destination location */ + + pout++; + } + + /* C was not found in the first n bytes of s2 */ + + return NULL; +} |