Function rt_strstr

src/klibc/kstring.c:285–312

 */
#ifndef RT_KLIBC_USING_USER_STRSTR
char *rt_strstr(const char *s1, const char *s2)
{
#ifdef RT_KLIBC_USING_LIBC_STRSTR
    return strstr(s1, s2);
#else
    int l1 = 0, l2 = 0;

    l2 = rt_strlen(s2);
    if (!l2)
    {
        return (char *)s1;
    }

    l1 = rt_strlen(s1);
    while (l1 >= l2)
    {
        l1 --;
        if (!rt_memcmp(s1, s2, l2))
        {
            return (char *)s1;
        }

        s1 ++;
    }

    return RT_NULL;
#endif /* RT_KLIBC_USING_LIBC_STRSTR */
}
#endif /* RT_KLIBC_USING_USER_STRSTR */
RTM_EXPORT(rt_strstr);