Add a few things necessary for openssl (not all)

tests/strings.c

@@ -0,0 +1,30 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <strings.h>
+
+int main() {
+    assert(!bcmp("hello", "hehe", 2));
+    assert(bcmp("hello", "haha", 2));
+
+    char* new = malloc(3);
+    bcopy("hi", new, 3); // include nul byte
+
+    assert(!strcasecmp("hi", new));
+    assert(!strcasecmp("hi", "HI"));
+    assert(!strncasecmp("hi", "HIHI", 2));
+
+    bzero(new, 1);
+    assert(*new == 0);
+    assert(*(new+1) == 'i');
+    assert(*(new+2) == 0);
+
+    assert(ffs(1) == 1);
+    assert(ffs(2) == 2);
+    assert(ffs(3) == 1);
+    assert(ffs(10) == 2);
+
+    char* str = "hihih";
+    assert(index(str, 'i') == str + 1);
+    assert(rindex(str, 'i') == str + 3);
+}