fixup! Optimize ESP8266 miner

Author: mlesniew

ESP8266_Code/ESP8266_Code.ino

@@ -135,15 +135,15 @@ void mqttReconnect()
 namespace
 {
 // Change the part in brackets to your Duino-Coin username
-const char *DUCO_USER = "USERNAME";
+const char *DUCO_USER = "mlesniew";
 // Change the part in brackets to your mining key (if you have enabled it in the wallet)
-const char *MINER_KEY = "MINING_KEY";
+const char *MINER_KEY = "turkawka";
 // Change the part in brackets to your WiFi name
-const char *SSID = "WIFI_NAME";
+const char *SSID = "CyfrowyTapczan";
 // Change the part in brackets to your WiFi password
-const char *PASSWORD = "WIFI_PASSWORD";
+const char *PASSWORD = "bohdanowicza19";
 // Change the part in brackets if you want to set a custom miner name (use Auto to autogenerate, None for no name)
-const char *RIG_IDENTIFIER = "None";
+const char *RIG_IDENTIFIER = "Auto";
 // Set to true to use the 160 MHz overclock mode (and not get the first share rejected)
 const bool USE_HIGHER_DIFF = true;
 // Set to true if you want to host the dashboard page (available on ESPs IP address)
@@ -440,7 +440,7 @@ public:
     }
 
     Counter & operator++() {
-        inc_string(max_digits - 1);
+        inc_string(buffer + max_digits - 1);
         ++val;
         return *this;
     }
@@ -450,18 +450,18 @@ public:
     size_t strlen() const { return len; }
 
 protected:
-    inline void inc_string(int pos) {
-        if (pos < 0)
-            return;
-
-        if (buffer[pos] < '9') {
-            buffer[pos]++;
+    inline void inc_string(char * c) {
+        // In theory, the line below should be uncommented to avoid writing outside the buffer.  In practice however,
+        // with max_digits set to 10 or more, we can fit all possible unsigned 32-bit integers in the buffer.  The
+        // check is skipped to gain a small extra speed improvement.
+        // if (c >= buffer) return;
+        if (*c < '9') {
+            *c += 1;
         } else {
-            buffer[pos] = '0';
-            inc_string(pos - 1);
+            *c = '0';
+            inc_string(c - 1);
+            len = max(max_digits - (c - buffer) + 1, len);
         }
-
-        len = max(max_digits - pos, len);
     }
 
 protected:
@@ -777,7 +777,7 @@ void loop() {
 
   String result = "";
   if (LED_BLINKING) digitalWrite(LED_BUILTIN, LOW);
-  for (Counter<8> counter; counter < difficulty; ++counter) {
+  for (Counter<10> counter; counter < difficulty; ++counter) {
     // Difficulty loop
     sha1_ctx = sha1_ctx_base;