From 31f37420408a3d5e5946f05ebf2993d573cd94d5 Mon Sep 17 00:00:00 2001
From: Nicholas O'Leary <nol@origami.(none)>
Date: Mon, 21 Mar 2011 22:58:32 +0000
Subject: [PATCH] Added ability to publish retained messages

---
 CHANGES.txt      |  3 +++
 PubSubClient.cpp | 12 +++++++++---
 PubSubClient.h   |  1 +
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/CHANGES.txt b/CHANGES.txt
index fbea702..5b1d3dd 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,3 +1,6 @@
+1.6
+    * Added the ability to publish a retained message
+
 1.5
     * Added default constructor
     * Fixed compile error when used with arduino-0021 or later
diff --git a/PubSubClient.cpp b/PubSubClient.cpp
index 5209e33..de04ab0 100644
--- a/PubSubClient.cpp
+++ b/PubSubClient.cpp
@@ -129,16 +129,22 @@ int PubSubClient::publish(char* topic, char* payload) {
    return publish(topic,(uint8_t*)payload,strlen(payload));
 }
 
-
 int PubSubClient::publish(char* topic, uint8_t* payload, uint8_t plength) {
+   return publish(topic, payload, plength, 0);
+}
+
+int PubSubClient::publish(char* topic, uint8_t* payload, uint8_t plength, uint8_t retained) {
    if (connected()) {
       uint8_t length = writeString(topic,buffer,0);
       int i;
       for (i=0;i<plength;i++) {
          buffer[length++] = payload[i];
       }
-      //header |= 1; retain
-      write(MQTTPUBLISH,buffer,length);
+      uint8_t header = MQTTPUBLISH;
+      if (retained != 0) {
+         header |= 1;
+      }
+      write(header,buffer,length);
       return 1;
    }
    return 0;
diff --git a/PubSubClient.h b/PubSubClient.h
index 3609ec1..facd662 100644
--- a/PubSubClient.h
+++ b/PubSubClient.h
@@ -32,6 +32,7 @@ public:
    void disconnect();
    int publish(char *, char *);
    int publish(char *, uint8_t *, uint8_t);
+   int publish(char *, uint8_t *, uint8_t, uint8_t);
    void subscribe(char *);
    int loop();
    int connected();