/**************************************************************************** * libs/libc/string//lib_strndup.c * * Copyright (C) 2011, 2013 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include "libc.h" /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: strndup * * Description: * The strndup() function is equivalent to the strdup() function, * duplicating the provided 's' in a new block of memory allocated as * if by using malloc(), with the exception being that strndup() copies * at most 'size' plus one bytes into the newly allocated memory, * terminating the new string with a NUL character. If the length of 's' * is larger than 'size', only 'size' bytes will be duplicated. If * 'size' is larger than the length of 's', all bytes in s will be * copied into the new memory buffer, including the terminating NUL * character. The newly created string will always be properly * terminated. * ****************************************************************************/ FAR char *strndup(FAR const char *s, size_t size) { FAR char *news = NULL; if (s) { /* Get the size of the new string (limited to size) */ size_t allocsize = strnlen(s, size); /* Allocate the new string, adding 1 for the NUL terminator */ news = (FAR char *)lib_malloc(allocsize + 1); if (news) { /* Copy the string into the allocated memory and add a NUL * terminator in any case. */ memcpy(news, s, allocsize); news[allocsize] = '\0'; } } return news; }