From ea628b4d207f9ffd5bdd8b4bf6d4378b46268b98 Mon Sep 17 00:00:00 2001 From: Atanas Filipov Date: Sun, 8 Jul 2018 17:52:05 +0300 Subject: Initial commit --- src/strnstr.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 src/strnstr.c (limited to 'src/strnstr.c') diff --git a/src/strnstr.c b/src/strnstr.c new file mode 100644 index 0000000..e195629 --- /dev/null +++ b/src/strnstr.c @@ -0,0 +1,60 @@ +/* + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1990, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is refactored by Atanas Filipov - it.feel.filipov@gmail.com + * + * 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 of the University 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 REGENTS 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 REGENTS 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. + */ + +#include +#include + +char * strnstr(const char *s, const char *find, size_t slen) +{assert((s) && (find)); + + char c, sc; + size_t len; + + if ((c = *find++) != '\0') { + + len = strlen(find); + do { + do { + if (slen-- < 1 || (sc = *s++) == '\0') { + return (NULL); + } + } while (sc != c); + + if (len > slen) { + return (NULL); + } + } while (strncmp(s, find, len) != 0); + s--; + } + return ((char *)s); +} -- cgit v1.2.3