nuttx/libs/libc/string/lib_strsep.c

83 lines
3.2 KiB
C

/****************************************************************************
* libs/libc/string/lib_strsep.c
*
* Copyright (C) 2019 Pinecone Inc. All rights reserved.
* Author: Xiang Xiao <xiaoxiang@pinecon.net>
*
* 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 <string.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: strsep
*
* Description:
* If *strp is NULL, the strsep() function returns NULL and does
* nothing else. Otherwise, this function finds the first token in the
* string *strp, that is delimited by one of the bytes in the string
* delim. This token is terminated by overwriting the delimiter with a
* null byte ('\0'), and *strp is updated to point past the token.
* In case no delimiter was found, the token is taken to be the entire
* string *strp, and *strp is made NULL.
*
* Returned Value:
* The strsep() function returns a pointer to the token, that is, it
* returns the original value of *strp.
*
****************************************************************************/
FAR char *strsep(FAR char **strp, FAR const char *delim)
{
FAR char *sbegin = *strp;
FAR char *end;
if !sbegin == NULL)
{
return NULL;
}
end = strpbrk(sbegin, delim);
if (end != NULL)
{
*end++ = '\0';
}
*strp = end;
return sbegin;
}