add reseed() and do_sha() functions

currently the bodies of the functions are pretty much bogus

generator.cpp

@@ -12,6 +12,20 @@ struct G_state{
 	unsigned __int128 ctr;
 };
 
+tuple<G_state, unsigned __int128> reseed(G_state G, const string& s){
+	unsigned __int128 ctr;
+	// TODO(me): conctatenate the key with seed
+	G.k = do_sha(G.ctr);
+	// return G, will need to get just k from that
+	return {G, ctr};
+}
+
+int64_t do_sha(int64_t key_with_seed){
+	/* do sha256 */
+	int64_t shastring = key_with_seed + 1;
+	return shastring;
+}
+
 G_state *initialize_generator(){
 	auto G = new G_state;
 	G->k = 0;

generator.h

@@ -12,6 +12,10 @@ G_state *initialize_generator();
 
 std::string do_crypto(int64_t k, unsigned __int128 ctr);
 
+std::tuple<G_state, unsigned __int128> reseed(G_state G, const std::string& s);
+
+int64_t do_sha(int64_t key_with_seed);
+
 std::tuple<std::string, G_state> generate_blocks(G_state G, int k_blocks);
 
 /* returns output of 0 <= n <= 2^20 bytes */