看了Linux内核代码linux/string.h中的一些字符串操作函数，有几个写的真是漂亮！
char * strstr(const char*, const char*)
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| /**
* strstr - Find the first substring in a %NUL terminated string
* @s1: The string to be searched
* @s2: The string to search for
*/
char *strstr(const char *s1, const char *s2)
{
int l1, l2;
l2 = strlen(s2);
if (!l2)
return (char *)s1;
l1 = strlen(s1);
while (l1 >= l2) {
l1--;
if (!memcmp(s1, s2, l2))
return (char *)s1;
s1++;
}
return NULL;
} |
void * memmove(void *, const void*)
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| /**
* memmove - Copy one area of memory to another
* @dest: Where to copy to
* @src: Where to copy from
* @count: The size of the area.
*
* Unlike memcpy(), memmove() copes with overlapping areas.
*/
void *memmove(void *dest, const void *src, size_t count)
{
char *tmp;
const char *s;
if (dest <= src) {
tmp = dest;
s = src;
while (count--)
*tmp++ = *s++;
}
else {
tmp = dest;
tmp += count;
s = src;
s += count;
while (count--)
*--tmp = *--s;
}
return dest;
} |
int strcmp(const char*, const char*)
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| /**
* strncmp - Compare two length-limited strings
* @cs: One string
* @ct: Another string
* @count: The maximum number of bytes to compare
*/
int strncmp(const char *cs, const char *ct, size_t count)
{
signed char __res = 0;
while (count) {
if ((__res = *cs - *ct++) != 0 || !*cs++)
break;
count--;
}
return __res;
} |
你好！除了代码，此处没有多少原创之物，皆为本人搜集、整理、总结之记录与心得，欢迎转载分享！转载时请尽量注明出处，将不胜感激。祝你健康、快乐！
linux的代码都是最牛的那些人写的。。自然不用说。。