diff options
author | andre <andre@FreeBSD.org> | 2005-08-25 18:26:58 +0000 |
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committer | andre <andre@FreeBSD.org> | 2005-08-25 18:26:58 +0000 |
commit | 45fd598f4942e0ea7d9bb2098d535eb046cfc00c (patch) | |
tree | 2f1fcdc8a52ba5e5b1514b1acb657de861faeded /lib/libc/string/memmem.c | |
parent | 07a0e1e154365c2461f41a99ec29ae4aa16d3905 (diff) | |
download | FreeBSD-src-45fd598f4942e0ea7d9bb2098d535eb046cfc00c.zip FreeBSD-src-45fd598f4942e0ea7d9bb2098d535eb046cfc00c.tar.gz |
Add the function memmem(3) as found in glibc and others.
It is the binary equivalent to strstr(3).
void *memmem(const void *big, size_t big_len,
const void *little, size_t little_len);
Submitted by: Pascal Gloor <pascal.gloor at spale.com>
MFC after: 3 days
Diffstat (limited to 'lib/libc/string/memmem.c')
-rw-r--r-- | lib/libc/string/memmem.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/lib/libc/string/memmem.c b/lib/libc/string/memmem.c new file mode 100644 index 0000000..0ac0a6d --- /dev/null +++ b/lib/libc/string/memmem.c @@ -0,0 +1,67 @@ +/*- + * 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(l, l_len, s, s_len) + 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; + + /* we need something to compare */ + if (l_len == 0 || s_len == 0) + return NULL; + + /* "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; +} |