use timeout in socket_recv fail loop

Expose variables to configure socket read and write timeouts in  sec and usec (microseconds) precision

README.md

@@ -2,15 +2,15 @@
 
 Implementation of the basic functionality of the Modbus TCP and UDP based protocol using PHP. 
 
-This is a fork of the original project at https://code.google.com/p/phpmodbus/
+**NOTE: This is a fork to fix & update the library code (and code alone). Notably, the tests are probably all broken.**
 
 > **What's new**
 > 
 > This fork adds a namespace and fixes issues encountered when porting to PHP 7
 
-**WARNING: Everything except the actual code in this repo may be broken and outdated.**
 
-Implemented features:
+## Implemented features
+
  * Modbus master
  * FC1 - Read coils 
  * FC2 - Read input discretes
@@ -22,18 +22,24 @@ Implemented features:
  * FC16 - Write multiple registers
  * FC23 - Read/Write multiple registers
 
-Example:
+
+## Requirements
+
+ * The PHP extension php_sockets.dll should be enabled (server php.ini file)
+
+ 
+## Example
 
 ```php
-require_once dirname(__FILE__) . '/Phpmodbus/ModbusMaster.php'; 
+use PHPModbus/ModbusMaster; 
+use PHPModbus/PhpType; 
 
 // Modbus master UDP
 $modbus = new ModbusMaster("192.168.1.1", "UDP"); 
 // Read multiple registers
 try {
     $recData = $modbus->readMultipleRegisters(0, 12288, 5); 
-}
+} catch (Exception $e) {
-catch (Exception $e) {
     // Print error information if any
     echo $modbus;
     echo $e;
@@ -43,7 +49,14 @@ catch (Exception $e) {
 echo PhpType::bytes2string($recData); 
 ```
 
-For more see [http://code.google.com/p/phpmodbus/downloads/list documentation] or [http://code.google.com/p/phpmodbus/wiki/FAQ FAQ].
+Use the `setTimeout($seconds)` and `setSocketTimeout($read_timeout_sec, $write_timeout_sec)` methods to adjust wait times.
+
+Most of the code is (to some extent) commented and documented with PhpDoc. You should get useful tooltips in your IDE.
+
+
+## GoogleCode legacy docs & downloads
+
+This project was originally hosted on (now defunct) Google Code. It's still archived here:
+
+* [GoogleCode Archived Repo](http://code.google.com/p/phpmodbus)
 
-Note: 
- * The PHP extension php_sockets.dll should be enabled (server php.ini file)

composer.json

@@ -11,6 +11,10 @@
     {
       "name": "Honza Krakora",
       "email": "krakora.jan@googlemail.com"
+    },
+    {
+      "name": "Ondřej Hruška",
+      "email": "ondra@ondrovo.com"
     }
   ],
   "autoload": {

examples/example_750841_Mmemory.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $ip = "192.192.15.51";
@@ -13,8 +13,7 @@ try {
 	$mw0address = 12288;
 	$quantity = 6;
 	$recData = $modbus->readMultipleRegisters($moduleId, $reference, $quantity);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	echo $modbus;
 	echo $e;
 	exit;
@@ -31,10 +30,10 @@ catch (Exception $e) {
 	<h1>Dump of M-memory from WAGO 750-84x series coupler.</h1>
 	<ul>
 		<li>PLC: 750-84x series</li>
-            <li>IP: <?php echo $ip?></li>
+		<li>IP: <?php echo $ip ?></li>
-            <li>Modbus module ID: <?php echo $moduleId?></li>
+		<li>Modbus module ID: <?php echo $moduleId ?></li>
-            <li>Modbus memory reference: <?php echo $reference?></li>
+		<li>Modbus memory reference: <?php echo $reference ?></li>
-            <li>Modbus memory quantity: <?php echo $quantity?></li>
+		<li>Modbus memory quantity: <?php echo $quantity ?></li>
 	</ul>
 
 	<h2>M-memory dump</h2>
@@ -46,12 +45,12 @@ catch (Exception $e) {
 			<td>value</td>
 		</tr>
 		<?php
-            for($i=0;$i<count($recData);$i+=2) {
+		for ($i = 0; $i < count($recData); $i += 2) {
 			?>
 			<tr>
-                <td><?php echo $i+$reference?></td>
+				<td><?php echo $i + $reference ?></td>
-                <td>MW<?php echo ($i + $reference - $mw0address)/2?></td>
+				<td>MW<?php echo ($i + $reference - $mw0address) / 2 ?></td>
-                <td><?php echo ($recData[$i] << 8)+ $recData[$i+1]?></td>
+				<td><?php echo ($recData[$i] << 8) + $recData[$i + 1] ?></td>
 			</tr>
 			<?php
 		}
@@ -59,9 +58,8 @@ catch (Exception $e) {
 	</table>
 
 	<h2>Modbus class status</h2>
-        <?php
+
-        echo $modbus;
+	<pre><?= $modbus ?></pre>
-        ?>
 
 	</body>
 </html>

examples/example_datatype.php

@@ -1,6 +1,7 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
+use PHPModbus\PhpType;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
@@ -9,8 +10,7 @@ try {
 	// FC 3
 	// read 10 words (20 bytes) from device ID=0, address=12288
 	$recData = $modbus->readMultipleRegisters(0, 12288, 10);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;
@@ -28,17 +28,17 @@ $values = array_chunk($recData, 4);
 
 // Get float from REAL interpretation
 echo "<h3>REAL to Float</h3>\n";
-foreach($values as $bytes)
+foreach ($values as $bytes)
 	echo PhpType::bytes2float($bytes) . "</br>";
 
 // Get integer from DINT interpretation
 echo "<h3>DINT to integer </h3>\n";
-foreach($values as $bytes)
+foreach ($values as $bytes)
 	echo PhpType::bytes2signedInt($bytes) . "</br>";
 
 // Get integer of float from DINT interpretation
 echo "<h3>DWORD to integer (or float) </h3>\n";
-foreach($values as $bytes)
+foreach ($values as $bytes)
 	echo PhpType::bytes2unsignedInt($bytes) . "</br>";
 
 echo "<h2>16 bit types</h2>\n";
@@ -47,15 +47,14 @@ $values = array_chunk($recData, 2);
 
 // Get signed integer from INT interpretation
 echo "<h3>INT to integer </h3>\n";
-foreach($values as $bytes)
+foreach ($values as $bytes)
 	echo PhpType::bytes2signedInt($bytes) . "</br>";
 
 // Get unsigned integer from WORD interpretation
 echo "<h3>WORD to integer </h3>\n";
-foreach($values as $bytes)
+foreach ($values as $bytes)
 	echo PhpType::bytes2unsignedInt($bytes) . "</br>";
 
 // Get string from STRING interpretation
 echo "<h3>STRING to string </h3>\n";
 echo PhpType::bytes2string($recData) . "</br>";
-?>

examples/example_fc1.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
@@ -8,8 +8,7 @@ $modbus = new ModbusMaster("192.192.15.51", "UDP");
 try {
 	// FC 1
 	$recData = $modbus->readCoils(0, 12288, 12);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;

examples/example_fc15.php

@@ -1,21 +1,22 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
 
-// Data to be writen
+// Data to be written - supports both 0/1 and booleans (true, false)
-$data = array(TRUE, FALSE, TRUE, TRUE, FALSE, TRUE, TRUE, TRUE, 
+$data = array(
-              TRUE, TRUE, TRUE, TRUE, FALSE, FALSE, FALSE, FALSE,
+	1, 0, 1, 1, 0, 1, 1, 1,
-              FALSE, FALSE, FALSE, FALSE, TRUE, TRUE, TRUE, TRUE,
+	1, 1, 1, 1, 0, 0, 0, 0,
-              TRUE, TRUE, TRUE, TRUE, TRUE, TRUE, TRUE, TRUE);
+	0, 0, 0, 0, 1, 1, 1, 1,
+	1, 1, 1, 1, 1, 1, 1, 1,
+);
 
 try {
 	// FC15
 	$modbus->writeMultipleCoils(0, 12288, $data);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;

examples/example_fc16.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
@@ -12,8 +12,7 @@ $dataTypes = array("WORD", "INT", "DINT", "REAL");
 try {
 	// FC16
 	$modbus->writeMultipleRegister(0, 12288, $data, $dataTypes);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;

examples/example_fc2.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
@@ -9,8 +9,7 @@ try {
 	// FC 2
 	// read 2 input bits from address 0x0 (Wago input image)
 	$recData = $modbus->readInputDiscretes(0, 0, 2);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;

examples/example_fc22.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
@@ -8,14 +8,13 @@ $modbus = new ModbusMaster("192.192.15.51", "UDP");
 // Data to be writen
 $bitValue = true;
 $bitNumber = 2;
-$andMask =  0xFFFF ^ pow(2, $bitNumber) ;
+$andMask = 0xFFFF ^ pow(2, $bitNumber);
-$orMask =  0x0000 ^ (pow(2, $bitNumber) * $bitValue ) ;
+$orMask = 0x0000 ^ (pow(2, $bitNumber) * $bitValue);
 
 try {
 	// FC22
 	$modbus->maskWriteRegister(0, 12288, $andMask, $orMask);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;
@@ -24,5 +23,3 @@ catch (Exception $e) {
 
 // Print status information
 echo $modbus;
-
-?>

examples/example_fc23.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
@@ -12,8 +12,7 @@ $dataTypes = array("WORD", "INT", "DINT", "REAL");
 try {
 	// FC23
 	$recData = $modbus->readWriteRegisters(0, 12288, 6, 12288, $data, $dataTypes);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;
@@ -27,5 +26,3 @@ echo "</br>Status:</br>" . $modbus;
 echo "</br>Data:</br>";
 print_r($recData);
 echo "</br>";
-
-?>

examples/example_fc3.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
@@ -8,8 +8,7 @@ $modbus = new ModbusMaster("192.192.15.51", "UDP");
 try {
 	// FC 3
 	$recData = $modbus->readMultipleRegisters(0, 12288, 6);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;
@@ -23,4 +22,3 @@ echo "</br>Status:</br>" . $modbus;
 echo "</br>Data:</br>";
 print_r($recData);
 echo "</br>";
-?>

examples/example_fc4.php

@@ -1,6 +1,6 @@
 <?php
 
-require_once dirname(__FILE__) . '/../../Phpmodbus/ModbusMasterUdp.php';
+use PHPModbus\ModbusMasterUdp;
 
 // Create Modbus object
 $modbus = new ModbusMasterUdp("192.192.15.51");
@@ -8,8 +8,7 @@ $modbus = new ModbusMasterUdp("192.192.15.51");
 try {
 	// Read input discretes - FC 4
 	$recData = $modbus->readMultipleInputRegisters(0, 0, 2);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;

examples/example_fc5.php

@@ -1,13 +1,13 @@
 <?php
 
-require_once dirname(__FILE__) . '/../../Phpmodbus/ModbusMasterUdp.php';
+use PHPModbus\ModbusMasterUdp;
 
 // Create Modbus object
 $modbus = new ModbusMasterUdp("192.192.15.51");
 
 // Data to be writen - TRUE, FALSE
-$data_true = array(TRUE);
+$data_true = array(true);
-$data_false = array(FALSE);
+$data_false = array(false);
 
 try {
 	// Write single coil - FC5
@@ -15,8 +15,7 @@ try {
 	$modbus->writeSingleCoil(0, 12289, $data_false);
 	$modbus->writeSingleCoil(0, 12290, $data_true);
 	$modbus->writeSingleCoil(0, 12291, $data_false);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;

examples/example_fc6.php

@@ -1,19 +1,17 @@
 <?php
 
-require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';
+use PHPModbus\ModbusMaster;
 
 // Create Modbus object
 $modbus = new ModbusMaster("192.192.15.51", "UDP");
 
 // Data to be writen
 $data = array(-1000);
-$dataTypes = array("INT");
 
 try {
 	// FC6
-    $modbus->writeSingleRegister(0, 12288, $data, $dataTypes);
+	$modbus->writeSingleRegister(0, 12288, $data);
-}
+} catch (Exception $e) {
-catch (Exception $e) {
 	// Print error information if any
 	echo $modbus;
 	echo $e;
@@ -22,5 +20,3 @@ catch (Exception $e) {
 
 // Print status information
 echo $modbus;
-
-?>

src/ModbusMaster.php

@@ -45,23 +45,38 @@ use Exception;
  */
 class ModbusMaster
 {
+	/** @var resource Communication socket */
 	private $sock;
 
+	/** @var string Modbus device IP address */
 	public $host = "192.168.1.1";
 
-	public $port = "502";
+	/** @var string gateway port */
+	public $port = 502;
 
-	public $client = "";
+	/** @var string (optional) client IP address */
+	public $client = ""; // TODO explanation?
 
-	public $client_port = "502";
+	/** @var string client port */
+	public $client_port = 502;
 
+	/** @var string ModbusMaster status messages (echo for debugging) */
 	public $status;
 
-	public $timeout_sec = 5; // Timeout 5 sec
+	/** @var float Total response timeout (seconds, decimals allowed) */
+	public $timeout_sec = 3;
 
-	public $endianness = 0; // Endianness codding (little endian == 0, big endian == 1)
+	/** @var float Socket read timeout (seconds, decimals allowed) */
+	public $socket_read_timeout_sec = 0.3; // 300 ms
 
-	public $socket_protocol = "UDP"; // Socket protocol (TCP, UDP)
+	/** @var float Socket write timeout (seconds, decimals allowed) */
+	public $socket_write_timeout_sec = 1;
+
+	/** @var int Endianness codding (0 = little endian = 0, 1 = big endian) */
+	public $endianness = 0; //
+
+	/** @var string Socket protocol (TCP, UDP) */
+	public $socket_protocol = "UDP";
 
 	/**
 	 * ModbusMaster
@@ -87,6 +102,22 @@ class ModbusMaster
 		return "<pre>" . $this->status . "</pre>";
 	}
 
+	/**
+	 * Convert float in seconds to array
+	 *
+	 * @param float $secs
+	 * @return array {sec: ..., usec: ...}
+	 */
+	private function secsToSecUsecArray($secs)
+	{
+		$remainder = $secs - floor($secs);
+
+		return [
+			'sec' => round($secs - $remainder),
+			'usec' => round($remainder * 1e6),
+		];
+	}
+
 	/**
 	 * connect
 	 *
@@ -111,18 +142,21 @@ class ModbusMaster
 		if (strlen($this->client) > 0) {
 			$result = socket_bind($this->sock, $this->client, $this->client_port);
 			if ($result === false) {
-				throw new Exception("socket_bind() failed.</br>Reason: ($result)" .
+				throw new Exception("socket_bind() failed. Reason: ($result)" .
 					socket_strerror(socket_last_error($this->sock)));
 			} else {
 				$this->status .= "Bound\n";
 			}
 		}
-		// Socket settings
+
-		socket_set_option($this->sock, SOL_SOCKET, SO_SNDTIMEO, array('sec' => 1, 'usec' => 0));
+		// Socket settings (send/write timeout)
+		$writeTimeout = $this->secsToSecUsecArray($this->socket_write_timeout_sec);
+		socket_set_option($this->sock, SOL_SOCKET, SO_SNDTIMEO, $writeTimeout);
+
 		// Connect the socket
 		$result = @socket_connect($this->sock, $this->host, $this->port);
 		if ($result === false) {
-			throw new Exception("socket_connect() failed.</br>Reason: ($result)" .
+			throw new Exception("socket_connect() failed. Reason: ($result)" .
 				socket_strerror(socket_last_error($this->sock)));
 		} else {
 			$this->status .= "Connected\n";
@@ -169,20 +203,26 @@ class ModbusMaster
 		$writesocks = null;
 		$exceptsocks = null;
 		$rec = "";
-		$lastAccess = time();
+		$totalReadTimeout = $this->timeout_sec;
-		while (socket_select($readsocks, $writesocks, $exceptsocks, 0, 300000) !== false) {
+		$lastAccess = microtime(true);
-			$this->status .= "Wait data ... \n";
+		$readStart = microtime(true);
+		$readTout = $this->secsToSecUsecArray($this->socket_read_timeout_sec);
+		while (false !== socket_select($readsocks, $writesocks, $exceptsocks, $readTout['sec'], $readTout['usec'])) {
 			if (in_array($this->sock, $readsocks)) {
-				while (@socket_recv($this->sock, $rec, 2000, 0)) {
+				if ($recn = @socket_recv($this->sock, $rec, 2000, 0)) { // read max 2000 bytes
-					$this->status .= "Data received\n";
+					$this->status .= "Data received \n";
 					return $rec;
 				}
-				$lastAccess = time();
+				$lastAccess = microtime(true);
+				if (microtime(true) - $readStart > $totalReadTimeout) {
+					throw new Exception("Read timed out, last error: " . socket_strerror(socket_last_error($this->sock)));
+				}
 			} else {
-				if (time() - $lastAccess >= $this->timeout_sec) {
+				$timeSpentWaiting = microtime(true) - $lastAccess;
-					throw new Exception("Watchdog time expired [ " .
+				if ($timeSpentWaiting >= $totalReadTimeout) {
-						$this->timeout_sec . " sec]!!! Connection to " .
+					throw new Exception(
-						$this->host . " is not established.");
+						"Watchdog time expired [ $totalReadTimeout sec ]!!! " .
+						"Connection to $this->host:$this->port is not established.");
 				}
 			}
 			$readsocks[] = $this->sock;
@@ -215,7 +255,7 @@ class ModbusMaster
 				0x06 => "SLAVE DEVICE BUSY",
 				0x08 => "MEMORY PARITY ERROR",
 				0x0A => "GATEWAY PATH UNAVAILABLE",
-				0x0B => "GATEWAY TARGET DEVICE FAILED TO RESPOND"
+				0x0B => "GATEWAY TARGET DEVICE FAILED TO RESPOND",
 			);
 			// get failure string
 			if (key_exists($failure_code, $failures)) {
@@ -1277,7 +1317,8 @@ class ModbusMaster
 		$referenceWrite,
 		$data,
 		$dataTypes
-	) {
+	)
+	{
 		$dataLen = 0;
 		// build data section
 		$buffer1 = "";
@@ -1324,7 +1365,7 @@ class ModbusMaster
 	 * FC23 response parser
 	 *
 	 * @param string $packet
-	 * @return array
+	 * @return array|false
 	 */
 	private function readWriteRegistersParser($packet)
 	{
@@ -1373,4 +1414,35 @@ class ModbusMaster
 		$str .= "\n";
 		return $str;
 	}
+
+	/**
+	 * Set data receive timeout.
+	 * Writes property timeout_sec
+	 *
+	 * @param float $seconds seconds
+	 */
+	public function setTimeout($seconds)
+	{
+		$this->timeout_sec = $seconds;
+	}
+
+	/**
+	 * Set socket read/write timeout. Null = no change.
+	 *
+	 * @param float|null $read_timeout_sec data read timeout (seconds, default 0.3)
+	 * @param float|null $write_timeout_sec data write timeout (seconds, default 1.0)
+	 * @internal param float $seconds seconds
+	 */
+	public function setSocketTimeout($read_timeout_sec, $write_timeout_sec)
+	{
+		// Set read timeout if given
+		if ($read_timeout_sec !== null) {
+			$this->socket_read_timeout_sec = $read_timeout_sec;
+		}
+
+		// Set write timeout if given
+		if ($write_timeout_sec !== null) {
+			$this->socket_write_timeout_sec = $write_timeout_sec;
+		}
+	}
 }