68 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			68 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C++
		
	
	
	
| /*-
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|  * Copyright (c) 2005 Pascal Gloor <pascal.gloor@spale.com>
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions
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|  * are met:
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|  * 1. Redistributions of source code must retain the above copyright
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|  *    notice, this list of conditions and the following disclaimer.
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|  * 2. Redistributions in binary form must reproduce the above copyright
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|  *    notice, this list of conditions and the following disclaimer in the
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|  *    documentation and/or other materials provided with the distribution.
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|  * 3. The name of the author may not be used to endorse or promote
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|  *    products derived from this software without specific prior written
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|  *    permission.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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|  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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|  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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|  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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|  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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|  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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|  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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|  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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|  * SUCH DAMAGE.
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|  */
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| 
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| #include <sys/cdefs.h>
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| #if 0
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| __FBSDID("$FreeBSD: src/lib/libc/string/memmem.c,v 1.1 2005/08/25 18:26:58 andre Exp $");
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| #endif
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| 
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| #include <string.h>
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| 
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| /*  Find the first occurrence of the byte string s in byte string l.
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|  */
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| 
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| extern "C" void *
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| memmem (const void *l, size_t l_len,
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| 	const void *s, size_t s_len)
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| {
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|   register char *cur, *last;
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|   const char *cl = (const char *)l;
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|   const char *cs = (const char *)s;
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| 
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|   /* we need something to compare */
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|   if (l_len == 0 || s_len == 0)
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|     return NULL;
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| 
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|   /* "s" must be smaller or equal to "l" */
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|   if (l_len < s_len)
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|     return NULL;
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| 
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|   /* special case where s_len == 1 */
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|   if (s_len == 1)
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|     return memchr (l, (int) *cs, l_len);
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| 
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|   /* the last position where its possible to find "s" in "l" */
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|   last = (char *) cl + l_len - s_len;
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| 
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|   for (cur = (char *) cl; cur <= last; cur++)
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|     if (cur[0] == cs[0] && memcmp (cur, cs, s_len) == 0)
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|       return cur;
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| 
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|   return NULL;
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| }
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