ref: a06125b256611ed9a97f7b1664beff5a6d27c52f
dir: /lib/c/src/strstr.c/
#include <string.h> #undef strstr char * strstr(const char *s1, const char *s2) { const char *p, *q; int c; c = *s2++; if (c == '\0') return (char *) s1; while (*s1) { if (*s1 != c) { ++s1; } else { p = s1++; for (q = s2; *q && *s1 == *q; ++s1, ++q) ; if (*q == '\0') return (char *) p; } } return NULL; }