/*- * Copyright (c) 2005 Pascal Gloor <pascal.gloor@spale.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. The name of the author may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <sys/cdefs.h> __FBSDID("$FreeBSD$"); #include <string.h> /* * Find the first occurrence of the byte string s in byte string l. */ void * memmem(const void *l, size_t l_len, const void *s, size_t s_len) { register char *cur, *last; const char *cl = (const char *)l; const char *cs = (const char *)s; /* empty "s" matches the beginning of "l" */ if (s_len == 0) return (void *)cl; /* "s" must be smaller or equal to "l" */ if (l_len < s_len) return NULL; /* special case where s_len == 1 */ if (s_len == 1) return memchr(l, (int)*cs, l_len); /* the last position where its possible to find "s" in "l" */ last = (char *)cl + l_len - s_len; for (cur = (char *)cl; cur <= last; cur++) if (cur[0] == cs[0] && memcmp(cur, cs, s_len) == 0) return cur; return NULL; } |