G'day,

after many uses I like to propose memmem(3) for inclusion into libc.
memmem(3) is similar to strstr(3) with the difference that it allows
searching for arbitary binary data patterns in an memory block, 
see man-page and source code included below fore more information.

I believe that this is very versatile function that may become handy for
many applications.

As always, I entertain your constructive comments.

Many thanks in advance

cheerio Berndt


----------------------- memmem.3 (txt) ------------------------
MEMMEM(3)                 NetBSD Programmer's Manual                 MEMMEM(3)

NAME
     memmem - locate a binary data pattern in a block of memory

LIBRARY
     Standard C Library (libc, -lc)

SYOPSIS
     #include <string.h>

     void *
     memmem(const void *b1, const void *b2, size_t len1, size_t len2);

DESCRIPTION
     The memmem() function locates the first occurence of a data pattern
     stored in b2 of size len2 in memory block b1 of size len1.

RETURN VALUES
     The memmem() function returns a pointer to the first occurence of data
     pattern b2 in memory block b1 or NULL if none is found.

SEE ALSO
     strstr(3),

STANDARDS
     The memmem() function is an extension to ANSI X3.159-1989 (``ANSI C'').

NetBSD 1.6                      Febrary 9, 2003                              1
----------------------- memmem.3 (txt) ------------------------


-------------------------- memmem.c ---------------------------
/* $NetBSD$ */

/*-
 * Copyright (c) 2003 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by 
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *        This product includes software developed by the NetBSD
 *        Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD$");
#endif /* LIBC_SCCS and not lint */

#if !defined(_KERNEL) && !defined(_STANDALONE)
#include <assert.h>
#include <string.h>
#else
#include <lib/libkern/libkern.h>
#define _DIAGASSERT(x)  (void)0
#define NULL            ((char *)0)
#endif

/*
 * memmem() returns the location of the first occurence of data
 * pattern b2 of size len2 in memory block b1 of size len1 or
 * NULL if none is found.
 */
void *
memmem(const void *b1, const void *b2, size_t len1, size_t len2)
{
        /* Initialize search pointer */
        char *sp = (char *) b1;

        /* Initialize pattern pointer */
        char *pp = (char *) b2;

        /* Intialize end of search address space pointer */
        char *eos   = sp + len1 - len2;

        /* Sanity check */
        if(!(b1 && b2 && len1 && len2))
                return NULL;

        while (sp <= eos) {
                if (*sp == *pp)
                        if (memcmp(sp, pp, len2) == 0)
                                return sp;

                        sp++;
        }

        return NULL;
}
-------------------------- memmem.c ---------------------------