Optimize reading of large files when using php-smbclient

src/NativeReadStream.php

@@ -0,0 +1,101 @@
+<?php
+/**
+ * Copyright (c) 2014 Robin Appelman <icewind@owncloud.com>
+ * This file is licensed under the Licensed under the MIT license:
+ * http://opensource.org/licenses/MIT
+ */
+
+namespace Icewind\SMB;
+
+/**
+ * Stream optimized for read only usage
+ */
+class NativeReadStream extends NativeStream {
+	const CHUNK_SIZE = 1048576; // 1MB chunks
+	/**
+	 * @var resource
+	 */
+	private $readBuffer = null;
+
+	private $bufferSize = 0;
+
+	private $pos = 0;
+
+	public function stream_open($path, $mode, $options, &$opened_path) {
+		$this->readBuffer = fopen('php://memory', 'r+');
+
+		return parent::stream_open($path, $mode, $options, $opened_path);
+
+	}
+
+	/**
+	 * Wrap a stream from libsmbclient-php into a regular php stream
+	 *
+	 * @param \Icewind\SMB\NativeState $state
+	 * @param resource $smbStream
+	 * @param string $mode
+	 * @param string $url
+	 * @return resource
+	 */
+	public static function wrap($state, $smbStream, $mode, $url) {
+		stream_wrapper_register('nativesmb', '\Icewind\SMB\NativeReadStream');
+		$context = stream_context_create(array(
+			'nativesmb' => array(
+				'state'  => $state,
+				'handle' => $smbStream,
+				'url'    => $url
+			)
+		));
+		$fh = fopen('nativesmb://', $mode, false, $context);
+		stream_wrapper_unregister('nativesmb');
+		return $fh;
+	}
+
+	public function stream_read($count) {
+		// php reads 8192 bytes at once
+		// however due to network latency etc, it's faster to read in larger chunks
+		// and buffer the result
+		if (!parent::stream_eof() && $this->bufferSize < $count) {
+			$remaining = $this->readBuffer;
+			$this->readBuffer = fopen('php://memory', 'r+');
+			$this->bufferSize = 0;
+			stream_copy_to_stream($remaining, $this->readBuffer);
+			$this->bufferSize += fwrite($this->readBuffer, parent::stream_read(self::CHUNK_SIZE));
+			fseek($this->readBuffer, 0);
+		}
+
+		$result = fread($this->readBuffer, $count);
+		$this->bufferSize -= $count;
+
+		$read = strlen($result);
+		$this->pos += $read;
+
+		return $result;
+	}
+
+	public function stream_seek($offset, $whence = SEEK_SET) {
+		$result = parent::stream_seek($offset, $whence);
+		if ($result) {
+			$this->readBuffer = fopen('php://memory', 'r+');
+			$this->bufferSize = 0;
+			$this->pos = parent::stream_tell();
+		}
+		return $result;
+	}
+
+	public function stream_eof() {
+		return $this->bufferSize <= 0 && parent::stream_eof();
+	}
+
+	public function stream_tell() {
+		return $this->pos;
+	}
+
+	public function stream_write($data) {
+		return false;
+	}
+
+	public function stream_truncate($size) {
+		return false;
+	}
+}

src/NativeShare.php

@@ -233,7 +233,7 @@ class NativeShare extends AbstractShare {
 	public function read($source) {
 		$url = $this->buildUrl($source);
 		$handle = $this->state->open($url, 'r');
-		return NativeStream::wrap($this->state, $handle, 'r', $url);
+		return NativeReadStream::wrap($this->state, $handle, 'r', $url);
 	}
 
 	/**

src/NativeStream.php

@@ -20,22 +20,22 @@ class NativeStream implements File {
 	/**
 	 * @var \Icewind\SMB\NativeState
 	 */
-	private $state;
+	protected $state;
 
 	/**
 	 * @var resource
 	 */
-	private $handle;
+	protected $handle;
 
 	/**
 	 * @var bool
 	 */
-	private $eof = false;
+	protected $eof = false;
 
 	/**
 	 * @var string
 	 */
-	private $url;
+	protected $url;
 
 	/**
 	 * Wrap a stream from libsmbclient-php into a regular php stream