Changed strings to ansistrings allowing topics and payloads to exceed…

… 255 bytes

README.md

@@ -9,12 +9,14 @@ Changes:
 --------
 
 1) Rewrote the reader thread loop so as to make it simpler and faster also fixes a bug whereby the
-client would segfault if the server went down.
+client would segfault if the server went down and a major bug where timeouts on rx would cause data corruption.
 
 2) Replaced the original client demo code with a simpler demo that does not use forms. I am using
 this in an embedded system with no display.
 
-3) Also includes the parts of Ararat Synapse required to build.
+3) Changed all strings to ansi strings so that it can have topics and payloads longer than 255 bytes. 
+
+4) Also includes the parts of Ararat Synapse required to build.
 
 To build the demo:
 ------------------

TMQTTClient/MQTT.pas

@@ -66,8 +66,8 @@ interface
 
   TMQTTClient = class(TObject)
       private
-        FClientID: string;
-        FHostname: string;
+        FClientID: ansistring;
+        FHostname: ansistring;
         FPort: Integer;
         FReadThread: TMQTTReadThread;
         FSocket: TTCPBlockSocket;
@@ -81,8 +81,8 @@   TMQTTClient = class(TObject)
         FUnSubAckEvent: TUnSubAckEvent;
         // Gets a next Message ID and increases the Message ID Increment
         function GetMessageID: TBytes;
-        // Takes a string and converts to An Array of Bytes preceded by 2 Length Bytes.
-        function StrToBytes(str: string; perpendLength: boolean): TUTF8Text;
+        // Takes a ansistring and converts to An Array of Bytes preceded by 2 Length Bytes.
+        function StrToBytes(str: ansistring; perpendLength: boolean): TUTF8Text;
         // Byte Array Helper Functions
         procedure AppendArray(var Dest: TUTF8Text; Source: Array of Byte);
         procedure CopyIntoArray(var DestArray: Array of Byte; SourceArray: Array of Byte; StartIndex: integer);
@@ -92,7 +92,7 @@   TMQTTClient = class(TObject)
         function RemainingLength(MessageLength: Integer): TRemainingLength;
         // Variable Header per command creation funcs
         function VariableHeaderConnect(KeepAlive: Word): TBytes;
-        function VariableHeaderPublish(topic: string): TBytes;
+        function VariableHeaderPublish(topic: ansistring): TBytes;
         function VariableHeaderSubscribe: TBytes;
         function VariableHeaderUnsubscribe: TBytes;
         // Helper Function - Puts the seperate component together into an Array of Bytes for transmission
@@ -105,21 +105,21 @@   TMQTTClient = class(TObject)
         procedure OnRTPingResp(Sender: TObject);
         procedure OnRTSubAck(Sender: TObject; MessageID: integer; GrantedQoS: integer);
         procedure OnRTUnSubAck(Sender: TObject; MessageID: integer);
-        procedure OnRTPublish(Sender: TObject; topic, payload: string);
+        procedure OnRTPublish(Sender: TObject; topic, payload: ansistring);
       public
         function isConnected: boolean;
         function Connect: boolean;
         function Disconnect: boolean;
         procedure ForceDisconnect;
-        function Publish(Topic: string; sPayload: string): boolean; overload;
-        function Publish(Topic: string; sPayload: string; Retain: boolean): boolean; overload;
-        function Subscribe(Topic: string): integer;
-        function Unsubscribe(Topic: string): integer;
+        function Publish(Topic: ansistring; sPayload: ansistring): boolean; overload;
+        function Publish(Topic: ansistring; sPayload: ansistring; Retain: boolean): boolean; overload;
+        function Subscribe(Topic: ansistring): integer;
+        function Unsubscribe(Topic: ansistring): integer;
         function PingReq: boolean;
-        constructor Create(Hostname: string; Port: integer); overload;
+        constructor Create(Hostname: ansistring; Port: integer); overload;
         destructor Destroy; override;
 
-        property ClientID : string read FClientID write FClientID;
+        property ClientID : ansistring read FClientID write FClientID;
         property OnConnAck : TConnAckEvent read FConnAckEvent write FConnAckEvent;
         property OnPublish : TPublishEvent read FPublishEvent write FPublishEvent;
         property OnPingResp : TPingRespEvent read FPingRespEvent write FPingRespEvent;
@@ -247,7 +247,7 @@ function TMQTTClient.PingReq: boolean;
   @param Retain   Should this message be retained for clients connecting subsequently
   @return Returns whether the Data was written successfully to the socket.
 ------------------------------------------------------------------------------*}
-function TMQTTClient.Publish(Topic, sPayload: string; Retain: boolean): boolean;
+function TMQTTClient.Publish(Topic, sPayload: ansistring; Retain: boolean): boolean;
 var
   Data: TBytes;
   FH: Byte;
@@ -273,7 +273,7 @@ function TMQTTClient.Publish(Topic, sPayload: string; Retain: boolean): boolean;
   @param sPayload   The Actual Payload of the message eg 18 degrees celcius
   @return Returns whether the Data was written successfully to the socket.
 ------------------------------------------------------------------------------*}
-function TMQTTClient.Publish(Topic, sPayload: string): boolean;
+function TMQTTClient.Publish(Topic, sPayload: ansistring): boolean;
 begin
   Publish(Topic, sPayload, False);
 end;
@@ -285,7 +285,7 @@ function TMQTTClient.Publish(Topic, sPayload: string): boolean;
   @return Returns the Message ID used to send the message for the purpose of comparing
   it to the Message ID used later in the SUBACK event handler.
 ------------------------------------------------------------------------------*}
-function TMQTTClient.Subscribe(Topic: string): integer;
+function TMQTTClient.Subscribe(Topic: ansistring): integer;
 var
   Data: TBytes;
   FH: Byte;
@@ -314,7 +314,7 @@ function TMQTTClient.Subscribe(Topic: string): integer;
   @return Returns the Message ID used to send the message for the purpose of comparing
   it to the Message ID used later in the UNSUBACK event handler.
 ------------------------------------------------------------------------------*}
-function TMQTTClient.Unsubscribe(Topic: string): integer;
+function TMQTTClient.Unsubscribe(Topic: ansistring): integer;
 var
   Data: TBytes;
   FH: Byte;
@@ -350,7 +350,7 @@ function TMQTTClient.isConnected: boolean;
   @param Port   Port of the MQTT Server
   @return Instance
 ------------------------------------------------------------------------------*}
-constructor TMQTTClient.Create(Hostname: string; Port: integer);
+constructor TMQTTClient.Create(Hostname: ansistring; Port: integer);
 begin
   inherited Create;
   Randomize;
@@ -404,7 +404,7 @@ function TMQTTClient.SocketWrite(Data: TBytes): boolean;
   end;
 end;
 
-function TMQTTClient.StrToBytes(str: string; perpendLength: boolean): TUTF8Text;
+function TMQTTClient.StrToBytes(str: ansistring; perpendLength: boolean): TUTF8Text;
 var
   i, offset: integer;
 begin
@@ -479,7 +479,7 @@ function TMQTTClient.VariableHeaderConnect(KeepAlive: Word): TBytes;
   Result[iByteIndex] := KeepAlive;
 end;
 
-function TMQTTClient.VariableHeaderPublish(topic: string): TBytes;
+function TMQTTClient.VariableHeaderPublish(topic: ansistring): TBytes;
 var
   BytesTopic: TUTF8Text;
 begin
@@ -550,7 +550,7 @@ procedure TMQTTClient.OnRTPingResp(Sender: TObject);
   if Assigned(OnPingResp) then OnPingResp(Self);
 end;
 
-procedure TMQTTClient.OnRTPublish(Sender: TObject; topic, payload: string);
+procedure TMQTTClient.OnRTPublish(Sender: TObject; topic, payload: ansistring);
 begin
   if Assigned(OnPublish) then OnPublish(Self, topic, payload);
 end;

TMQTTClient/MQTTReadThread.pas

@@ -50,7 +50,7 @@ interface
   PTCPBlockSocket = ^TTCPBlockSocket;
 
   TConnAckEvent = procedure (Sender: TObject; ReturnCode: integer) of object;
-  TPublishEvent = procedure (Sender: TObject; topic, payload: string) of object;
+  TPublishEvent = procedure (Sender: TObject; topic, payload: ansistring) of object;
   TPingRespEvent = procedure (Sender: TObject) of object;
   TSubAckEvent = procedure (Sender: TObject; MessageID: integer; GrantedQoS: integer) of object;
   TUnSubAckEvent = procedure (Sender: TObject; MessageID: integer) of object;
@@ -67,7 +67,7 @@   TMQTTReadThread = class(TThread)
     FUnSubAckEvent: TUnSubAckEvent;
     // This takes a 1-4 Byte Remaining Length bytes as per the spec and returns the Length value it represents
     // Increases the size of the Dest array and Appends NewBytes to the end of DestArray 
-    // Takes a 2 Byte Length array and returns the length of the string it preceeds as per the spec.
+    // Takes a 2 Byte Length array and returns the length of the ansistring it preceeds as per the spec.
     function BytesToStrLength(LengthBytes: TBytes): integer;
     // This is our data processing and event firing command. To be called via Synchronize.
     procedure HandleData;
@@ -158,8 +158,8 @@ procedure TMQTTReadThread.HandleData;
   MessageType: Byte;
   DataLen: integer;
   QoS: integer;
-  Topic: string;
-  Payload: string;
+  Topic: ansistring;
+  Payload: ansistring;
   ResponseVH: TBytes;
   ConnectReturn: Integer;
 begin

examples/embeddedApp/embeddedApp.pas

@@ -59,7 +59,7 @@
     Procedure OnPingResp(Sender: TObject);
     Procedure OnSubAck(Sender: TObject; MessageID : longint; GrantedQoS : longint);
     Procedure OnUnSubAck(Sender: TObject);
-    Procedure OnPublish(Sender: TObject; topic, payload: String);
+    Procedure OnPublish(Sender: TObject; topic, payload: ansistring);
 public
     Procedure run ();
   End;
@@ -69,7 +69,7 @@
   writeln ('Connection Acknowledged, Return Code: ' + IntToStr(Ord(ReturnCode)));
 End;
 
-Procedure TembeddedApp.OnPublish(Sender: TObject; topic, payload: String);
+Procedure TembeddedApp.OnPublish(Sender: TObject; topic, payload: ansistring);
 Begin
   writeln ('Publish Received. Topic: '+ topic + ' Payload: ' + payload);
 End;

examples/embeddedApp/payload.txt

@@ -1 +1,33 @@
-0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789;
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
+All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.