如何在一段内存中搜索一个十六进制串？
比如有长度为N，首地址为P的内存，搜索其中的内容是否包含有“001122ff”这样的串？如何能高效搜索？谢谢
[解决办法]
可以百度一下：KMP算法，BM算法。
参考：
http://www.cnblogs.com/whyandinside/archive/2012/06/03/2532651.html
[解决办法]
http://bbs.csdn.net/topics/390312862
[解决办法]
仅供参考
char * __cdecl strnstrn(const char * str1,int cnt1,const char * str2,int cnt2,int offs) {
char *cp=(char *)(str1+offs);
char *s1,*s2;
int nn;
if (offs+cnt2>cnt1) return(NULL);
while (1) {
s1=cp;
s2=(char *) str2;
nn=0;
while (1) {
if (fi[nn]==0) {
if (*s1-*s2) break;//
}
if (ri[nn]==1) rb[nn]=*s1;
s1++;
s2++;
nn++;
if (nn>=cnt2) return(cp);
}
cp++;
if (cp>=str1+cnt1) break;//
}
return(NULL);
}
/*-
* 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: src/lib/libc/string/memmem.c,v 1.2.2.1.4.1 2010/06/14 02:09:06 kensmith Exp $");
#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;
/* we need something to compare */
if (l_len == 0
[解决办法]
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;
}