[ticket/11912] Add phpbb mimetype guesser

Mimetype guesser will be used as front-end file for mimetype guessing.

PHPBB3-11912

phpBB/phpbb/mimetype/guesser.php

@@ -0,0 +1,105 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2013 phpBB Group
+* @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+*
+*/
+
+namespace phpbb\mimetype;
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+* @package mimetype
+*/
+
+class guesser
+{
+	/**
+	* @var mimetype guessers
+	*/
+	protected $guessers;
+
+	/**
+	* Construct a mimetype guesser object
+	*
+	* @param array $mimetype_guessers Mimetype guesser service collection
+	*/
+	public function __construct($mimetype_guessers)
+	{
+		$this->register_guessers($mimetype_guessers);
+	}
+
+	/**
+	* Register MimeTypeGuessers
+	*
+	* @param array $mimetype_guessers Mimetype guesser service collection
+	*
+	* @throws \LogicException If incorrect or not mimetype guessers have
+	*			been supplied to class
+	*/
+	protected function register_guessers($mimetype_guessers)
+	{
+		foreach ($mimetype_guessers as $guesser)
+		{
+			$is_supported = (method_exists($guesser, 'is_supported')) ? 'is_supported' : '';
+			$is_supported = (method_exists($guesser, 'isSupported')) ? 'isSupported' : $is_supported;
+
+			if (empty($is_supported))
+			{
+				throw new \LogicException('Incorrect mimetype guesser supplied.');
+			}
+
+			if ($guesser->$is_supported())
+			{
+				$this->guessers[] = $guesser;
+			}
+		}
+
+		if (empty($this->guessers))
+		{
+			throw new \LogicException('No mimetype guesser supplied.');
+		}
+	}
+
+	/**
+	* Guess mimetype of supplied file
+	*
+	* @param string $file Path to file
+	*
+	* @return string Guess for mimetype of file
+	*/
+	public function guess($file)
+	{
+		if (!is_file($file))
+		{
+			return false;
+		}
+
+		if (!is_readable($file))
+		{
+			return false;
+		}
+
+		foreach ($this->guessers as $guesser)
+		{
+			$mimetype = $guesser->guess($file);
+
+			// Try to guess something that is not the fallback application/octet-stream
+			if ($mimetype !== null && $mimetype !== 'application/octet-stream')
+			{
+				return $mimetype;
+			}
+		}
+		// Return any mimetype if we got a result or the fallback value
+		return (!empty($mimetype)) ? $mimetype : 'application/octet-stream';
+	}
+}