Merge pull request #365 from czaraugust/master

Adding some speed improvments

.gitignore

@@ -1 +1,5 @@
 tests/bin
+.pioenvs
+.piolibdeps
+.clang_complete
+.gcc-flags.json

examples/mqtt_esp8266/mqtt_esp8266.ino

@@ -1,26 +1,21 @@
 /*
  Basic ESP8266 MQTT example
-
  This sketch demonstrates the capabilities of the pubsub library in combination
  with the ESP8266 board/library.
-
  It connects to an MQTT server then:
   - publishes "hello world" to the topic "outTopic" every two seconds
   - subscribes to the topic "inTopic", printing out any messages
     it receives. NB - it assumes the received payloads are strings not binary
   - If the first character of the topic "inTopic" is an 1, switch ON the ESP Led,
     else switch it off
-
  It will reconnect to the server if the connection is lost using a blocking
  reconnect function. See the 'mqtt_reconnect_nonblocking' example for how to
  achieve the same result without blocking the main loop.
-
  To install the ESP8266 board, (using Arduino 1.6.4+):
   - Add the following 3rd party board manager under "File -> Preferences -> Additional Boards Manager URLs":
        http://arduino.esp8266.com/stable/package_esp8266com_index.json
   - Open the "Tools -> Board -> Board Manager" and click install for the ESP8266"
   - Select your ESP8266 in "Tools -> Board"
-
 */
 
 #include <ESP8266WiFi.h>

src/PubSubClient.cpp

@@ -1,4 +1,5 @@
 /*
+
   PubSubClient.cpp - A simple client for MQTT.
   Nick O'Leary
   http://knolleary.net
@@ -269,7 +270,7 @@ uint16_t PubSubClient::readPacket(uint8_t* lengthLength) {
         if(!readByte(&digit)) return 0;
         buffer[len++] = digit;
         length += (digit & 127) * multiplier;
-        multiplier *= 128;
+        multiplier <<=7; //multiplier *= 128
     } while ((digit & 128) != 0);
     *lengthLength = len-1;
 
@@ -432,8 +433,8 @@ boolean PubSubClient::publish_P(const char* topic, const uint8_t* payload, unsig
     buffer[pos++] = header;
     len = plength + 2 + tlen;
     do {
-        digit = len % 128;
-        len = len / 128;
+        digit = len  & 127; //digit = len %128
+        len >>= 7; //len = len / 128
         if (len > 0) {
             digit |= 0x80;
         }
@@ -492,8 +493,9 @@ size_t PubSubClient::buildHeader(uint8_t header, uint8_t* buf, uint16_t length)
     uint8_t pos = 0;
     uint16_t len = length;
     do {
-        digit = len % 128;
-        len = len / 128;
+
+        digit = len  & 127; //digit = len %128
+        len >>= 7; //len = len / 128
         if (len > 0) {
             digit |= 0x80;
         }