8 files changed, 2244 insertions, 0 deletions
diff --git a/phpBB/includes/template/compile.php b/phpBB/includes/template/compile.php
new file mode 100644
index 0000000000..8d8560ded5
--- /dev/null
+++ b/phpBB/includes/template/compile.php
@@ -0,0 +1,122 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2005 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+stream_filter_register('phpbb_template', 'phpbb_template_filter');
+
+/**
+* Extension of template class - Functions needed for compiling templates only.
+*
+* @package phpBB3
+* @uses template_filter As a PHP stream filter to perform compilation of templates
+*/
+class phpbb_template_compile
+{
+	/**
+	* Whether <!-- PHP --> tags are allowed
+	*
+	* @var bool
+	*/
+	private $allow_php;
+
+	/**
+	* Constructor.
+	*
+	* @param bool @allow_php Whether PHP code will be allowed in templates (inline PHP code, PHP tag and INCLUDEPHP tag)
+	*/
+	public function __construct($allow_php)
+	{
+		$this->allow_php = $allow_php;
+	}
+
+	/**
+	* Compiles template in $source_file and writes compiled template to
+	* cache directory
+	*
+	* @param string $handle Template handle to compile
+	* @param string $source_file Source template file
+	* @return bool Return true on success otherwise false
+	*/
+	public function compile_file_to_file($source_file, $compiled_file)
+	{
+		$source_handle = @fopen($source_file, 'rb');
+		$destination_handle = @fopen($compiled_file, 'wb');
+
+		if (!$source_handle || !$destination_handle)
+		{
+			return false;
+		}
+
+		@flock($destination_handle, LOCK_EX);
+
+		$this->compile_stream_to_stream($source_handle, $destination_handle);
+
+		@fclose($source_handle);
+		@flock($destination_handle, LOCK_UN);
+		@fclose($destination_handle);
+
+		phpbb_chmod($compiled_file, CHMOD_READ | CHMOD_WRITE);
+
+		clearstatcache();
+
+		return true;
+	}
+
+	/**
+	* Compiles a template located at $source_file.
+	*
+	* Returns PHP source suitable for eval().
+	*
+	* @param string $source_file Source template file
+	* @return string|bool Return compiled code on successful compilation otherwise false
+	*/
+	public function compile_file($source_file)
+	{
+		$source_handle = @fopen($source_file, 'rb');
+		$destination_handle = @fopen('php://temp' ,'r+b');
+
+		if (!$source_handle || !$destination_handle)
+		{
+			return false;
+		}
+
+		$this->compile_stream_to_stream($source_handle, $destination_handle);
+
+		@fclose($source_handle);
+
+		rewind($destination_handle);
+		$contents = stream_get_contents($destination_handle);
+		@fclose($dest_handle);
+
+		return $contents;
+	}
+
+	/**
+	* Compiles contents of $source_stream into $dest_stream.
+	*
+	* A stream filter is appended to $source_stream as part of the
+	* process.
+	*
+	* @param resource $source_stream Source stream
+	* @param resource $dest_stream Destination stream
+	* @return void
+	*/
+	private function compile_stream_to_stream($source_stream, $dest_stream)
+	{
+		stream_filter_append($source_stream, 'phpbb_template', null, array('allow_php' => $this->allow_php));
+		stream_copy_to_stream($source_stream, $dest_stream);
+	}
+}
diff --git a/phpBB/includes/template/context.php b/phpBB/includes/template/context.php
new file mode 100644
index 0000000000..f85f86a0ec
--- /dev/null
+++ b/phpBB/includes/template/context.php
@@ -0,0 +1,342 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2011 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+* Stores variables assigned to template.
+*
+* @package phpBB3
+*/
+class phpbb_template_context
+{
+	/**
+	* variable that holds all the data we'll be substituting into
+	* the compiled templates. Takes form:
+	* --> $this->tpldata[block][iteration#][child][iteration#][child2][iteration#][variablename] == value
+	* if it's a root-level variable, it'll be like this:
+	* --> $this->tpldata[.][0][varname] == value
+	*
+	* @var array
+	*/
+	private $tpldata = array('.' => array(0 => array()));
+
+	/**
+	* @var array Reference to template->tpldata['.'][0]
+	*/
+	private $rootref;
+
+	public function __construct()
+	{
+		$this->clear();
+	}
+
+	/**
+	* Clears template data set.
+	*/
+	public function clear()
+	{
+		$this->tpldata = array('.' => array(0 => array()));
+		$this->rootref = &$this->tpldata['.'][0];
+	}
+
+	/**
+	* Assign a single variable to a single key
+	*
+	* @param string $varname Variable name
+	* @param string $varval Value to assign to variable
+	*/
+	public function assign_var($varname, $varval)
+	{
+		$this->rootref[$varname] = $varval;
+
+		return true;
+	}
+
+	/**
+	* Returns a reference to template data array.
+	*
+	* This function is public so that template renderer may invoke it.
+	* Users should alter template variables via functions in phpbb_template.
+	*
+	* Note: modifying returned array will affect data stored in the context.
+	*
+	* @return array template data
+	*/
+	public function &get_data_ref()
+	{
+		// returning a reference directly is not
+		// something php is capable of doing
+		$ref = &$this->tpldata;
+		return $ref;
+	}
+
+	/**
+	* Returns a reference to template root scope.
+	*
+	* This function is public so that template renderer may invoke it.
+	* Users should not need to invoke this function.
+	*
+	* Note: modifying returned array will affect data stored in the context.
+	*
+	* @return array template data
+	*/
+	public function &get_root_ref()
+	{
+		// rootref is already a reference
+		return $this->rootref;
+	}
+
+	/**
+	* Assign key variable pairs from an array to a specified block
+	*
+	* @param string $blockname Name of block to assign $vararray to
+	* @param array $vararray A hash of variable name => value pairs
+	*/
+	public function assign_block_vars($blockname, array $vararray)
+	{
+		if (strpos($blockname, '.') !== false)
+		{
+			// Nested block.
+			$blocks = explode('.', $blockname);
+			$blockcount = sizeof($blocks) - 1;
+
+			$str = &$this->tpldata;
+			for ($i = 0; $i < $blockcount; $i++)
+			{
+				$str = &$str[$blocks[$i]];
+				$str = &$str[sizeof($str) - 1];
+			}
+
+			$s_row_count = isset($str[$blocks[$blockcount]]) ? sizeof($str[$blocks[$blockcount]]) : 0;
+			$vararray['S_ROW_COUNT'] = $s_row_count;
+
+			// Assign S_FIRST_ROW
+			if (!$s_row_count)
+			{
+				$vararray['S_FIRST_ROW'] = true;
+			}
+
+			// Now the tricky part, we always assign S_LAST_ROW and remove the entry before
+			// This is much more clever than going through the complete template data on display (phew)
+			$vararray['S_LAST_ROW'] = true;
+			if ($s_row_count > 0)
+			{
+				unset($str[$blocks[$blockcount]][($s_row_count - 1)]['S_LAST_ROW']);
+			}
+
+			// Now we add the block that we're actually assigning to.
+			// We're adding a new iteration to this block with the given
+			// variable assignments.
+			$str[$blocks[$blockcount]][] = $vararray;
+		}
+		else
+		{
+			// Top-level block.
+			$s_row_count = (isset($this->tpldata[$blockname])) ? sizeof($this->tpldata[$blockname]) : 0;
+			$vararray['S_ROW_COUNT'] = $s_row_count;
+
+			// Assign S_FIRST_ROW
+			if (!$s_row_count)
+			{
+				$vararray['S_FIRST_ROW'] = true;
+			}
+
+			// We always assign S_LAST_ROW and remove the entry before
+			$vararray['S_LAST_ROW'] = true;
+			if ($s_row_count > 0)
+			{
+				unset($this->tpldata[$blockname][($s_row_count - 1)]['S_LAST_ROW']);
+			}
+
+			// Add a new iteration to this block with the variable assignments we were given.
+			$this->tpldata[$blockname][] = $vararray;
+		}
+
+		return true;
+	}
+
+	/**
+	* Change already assigned key variable pair (one-dimensional - single loop entry)
+	*
+	* An example of how to use this function:
+	* {@example alter_block_array.php}
+	*
+	* @param	string	$blockname	the blockname, for example 'loop'
+	* @param	array	$vararray	the var array to insert/add or merge
+	* @param	mixed	$key		Key to search for
+	*
+	* array: KEY => VALUE [the key/value pair to search for within the loop to determine the correct position]
+	*
+	* int: Position [the position to change or insert at directly given]
+	*
+	* If key is false the position is set to 0
+	* If key is true the position is set to the last entry
+	*
+	* @param	string	$mode		Mode to execute (valid modes are 'insert' and 'change')
+	*
+	*	If insert, the vararray is inserted at the given position (position counting from zero).
+	*	If change, the current block gets merged with the vararray (resulting in new key/value pairs be added and existing keys be replaced by the new value).
+	*
+	* Since counting begins by zero, inserting at the last position will result in this array: array(vararray, last positioned array)
+	* and inserting at position 1 will result in this array: array(first positioned array, vararray, following vars)
+	*
+	* @return bool false on error, true on success
+	*/
+	public function alter_block_array($blockname, array $vararray, $key = false, $mode = 'insert')
+	{
+		if (strpos($blockname, '.') !== false)
+		{
+			// Nested block.
+			$blocks = explode('.', $blockname);
+			$blockcount = sizeof($blocks) - 1;
+
+			$block = &$this->tpldata;
+			for ($i = 0; $i < $blockcount; $i++)
+			{
+				if (($pos = strpos($blocks[$i], '[')) !== false)
+				{
+					$name = substr($blocks[$i], 0, $pos);
+
+					if (strpos($blocks[$i], '[]') === $pos)
+					{
+						$index = sizeof($block[$name]) - 1;
+					}
+					else
+					{
+						$index = min((int) substr($blocks[$i], $pos + 1, -1), sizeof($block[$name]) - 1);
+					}
+				}
+				else
+				{
+					$name = $blocks[$i];
+					$index = sizeof($block[$name]) - 1;
+				}
+				$block = &$block[$name];
+				$block = &$block[$index];
+			}
+
+			$block = &$block[$blocks[$i]]; // Traverse the last block
+		}
+		else
+		{
+			// Top-level block.
+			$block = &$this->tpldata[$blockname];
+		}
+
+		// Change key to zero (change first position) if false and to last position if true
+		if ($key === false || $key === true)
+		{
+			$key = ($key === false) ? 0 : sizeof($block);
+		}
+
+		// Get correct position if array given
+		if (is_array($key))
+		{
+			// Search array to get correct position
+			list($search_key, $search_value) = @each($key);
+
+			$key = NULL;
+			foreach ($block as $i => $val_ary)
+			{
+				if ($val_ary[$search_key] === $search_value)
+				{
+					$key = $i;
+					break;
+				}
+			}
+
+			// key/value pair not found
+			if ($key === NULL)
+			{
+				return false;
+			}
+		}
+
+		// Insert Block
+		if ($mode == 'insert')
+		{
+			// Make sure we are not exceeding the last iteration
+			if ($key >= sizeof($this->tpldata[$blockname]))
+			{
+				$key = sizeof($this->tpldata[$blockname]);
+				unset($this->tpldata[$blockname][($key - 1)]['S_LAST_ROW']);
+				$vararray['S_LAST_ROW'] = true;
+			}
+			else if ($key === 0)
+			{
+				unset($this->tpldata[$blockname][0]['S_FIRST_ROW']);
+				$vararray['S_FIRST_ROW'] = true;
+			}
+
+			// Re-position template blocks
+			for ($i = sizeof($block); $i > $key; $i--)
+			{
+				$block[$i] = $block[$i-1];
+			}
+
+			// Insert vararray at given position
+			$block[$key] = $vararray;
+
+			return true;
+		}
+
+		// Which block to change?
+		if ($mode == 'change')
+		{
+			if ($key == sizeof($block))
+			{
+				$key--;
+			}
+
+			$block[$key] = array_merge($block[$key], $vararray);
+
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	* Reset/empty complete block
+	*
+	* @param string $blockname Name of block to destroy
+	*/
+	public function destroy_block_vars($blockname)
+	{
+		if (strpos($blockname, '.') !== false)
+		{
+			// Nested block.
+			$blocks = explode('.', $blockname);
+			$blockcount = sizeof($blocks) - 1;
+
+			$str = &$this->tpldata;
+			for ($i = 0; $i < $blockcount; $i++)
+			{
+				$str = &$str[$blocks[$i]];
+				$str = &$str[sizeof($str) - 1];
+			}
+
+			unset($str[$blocks[$blockcount]]);
+		}
+		else
+		{
+			// Top-level block.
+			unset($this->tpldata[$blockname]);
+		}
+
+		return true;
+	}
+}
diff --git a/phpBB/includes/template/filter.php b/phpBB/includes/template/filter.php
new file mode 100644
index 0000000000..1d1d92378e
--- /dev/null
+++ b/phpBB/includes/template/filter.php
@@ -0,0 +1,923 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2011 phpBB Group, sections (c) 2001 ispi of Lincoln Inc
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+* The template filter that does the actual compilation
+*
+* psoTFX, phpBB Development Team - Completion of file caching, decompilation
+* routines and implementation of conditionals/keywords and associated changes
+*
+* The interface was inspired by PHPLib templates, and the template file (formats are
+* quite similar)
+*
+* The keyword/conditional implementation is currently based on sections of code from
+* the Smarty templating engine (c) 2001 ispi of Lincoln, Inc. which is released
+* (on its own and in whole) under the LGPL. Section 3 of the LGPL states that any code
+* derived from an LGPL application may be relicenced under the GPL, this applies
+* to this source
+*
+* DEFINE directive inspired by a request by Cyberalien
+*
+* @see template_compile
+* @package phpBB3
+*/
+class phpbb_template_filter extends php_user_filter
+{
+	const REGEX_NS = '[a-z_][a-z_0-9]+';
+
+	const REGEX_VAR = '[A-Z_][A-Z_0-9]+';
+
+	const REGEX_TAG = '<!-- ([A-Z][A-Z_0-9]+)(?: (.*?) ?)?-->';
+
+	const REGEX_TOKENS = '~<!-- ([A-Z][A-Z_0-9]+)(?: (.*?) ?)?-->|{((?:[a-z_][a-z_0-9]+\.)*\\$?[A-Z][A-Z_0-9]+)}~';
+
+	/**
+	* @var array
+	*/
+	private $block_names = array();
+
+	/**
+	* @var array
+	*/
+	private $block_else_level = array();
+
+	/**
+	* @var string
+	*/
+	private $chunk;
+
+	/**
+	* @var bool
+	*/
+	private $in_php;
+
+	/**
+	* Whether inline PHP code, <!-- PHP --> and <!-- INCLUDEPHP --> tags
+	* are allowed. If this is false all PHP code will be silently
+	* removed from the template during compilation.
+	*
+	* @var bool
+	*/
+	private $allow_php;
+
+	/**
+	* Stream filter
+	*
+	* Is invoked for evey chunk of the stream, allowing us
+	* to work on a chunk at a time, which saves memory.
+	*/
+	public function filter($in, $out, &$consumed, $closing)
+	{
+		$written = false;
+		$first = false;
+
+		while ($bucket = stream_bucket_make_writeable($in))
+		{
+			$consumed += $bucket->datalen;
+
+			$data = $this->chunk . $bucket->data;
+			$last_nl = strrpos($data, "\n");
+			$this->chunk = substr($data, $last_nl);
+			$data = substr($data, 0, $last_nl);
+
+			if (!strlen($data))
+			{
+				continue;
+			}
+
+			$written = true;
+
+			$data = $this->compile($data);
+			if (!$first)
+			{
+				$data = $this->prepend_preamble($data);
+				$first = false;
+			}
+			$bucket->data = $data;
+			$bucket->datalen = strlen($bucket->data);
+			stream_bucket_append($out, $bucket);
+		}
+
+		if ($closing && strlen($this->chunk))
+		{
+			$written = true;
+			$bucket = stream_bucket_new($this->stream, $this->compile($this->chunk));
+			stream_bucket_append($out, $bucket);
+		}
+
+		return $written ? PSFS_PASS_ON : PSFS_FEED_ME;
+	}
+
+	/**
+	* Initializer, called on creation.
+	*
+	* Get the allow_php option from params, which is passed
+	* to stream_filter_append.
+	*/
+	public function onCreate()
+	{
+		$this->chunk = '';
+		$this->in_php = false;
+		$this->allow_php = $this->params['allow_php'];
+		return true;
+	}
+
+	/**
+	* Compiles a chunk of template.
+	*
+	* The chunk must comprise of one or more complete lines from the source
+	* template.
+	*
+	* @param string $data Chunk of source template to compile
+	* @return string Compiled PHP/HTML code
+	*/
+	private function compile($data)
+	{
+		$block_start_in_php = $this->in_php;
+
+		$data = preg_replace('#<(?:[\\?%]|script)#s', '<?php echo\'\\0\';?>', $data);
+		$data = preg_replace_callback(self::REGEX_TOKENS, array($this, 'replace'), $data);
+
+		// Remove php
+		if (!$this->allow_php)
+		{
+			if ($block_start_in_php
+				&& $this->in_php
+				&& strpos($data, '<!-- PHP -->') === false
+				&& strpos($data, '<!-- ENDPHP -->') === false)
+			{
+				// This is just php code
+				return '';
+			}
+			$data = preg_replace('~^.*?<!-- ENDPHP -->~', '', $data);
+			$data = preg_replace('~<!-- PHP -->.*?<!-- ENDPHP -->~', '', $data);
+			$data = preg_replace('~<!-- ENDPHP -->.*?$~', '', $data);
+		}
+
+		/*
+			Preserve whitespace.
+			PHP removes a newline after the closing tag (if it's there). This is by design.
+
+
+			Consider the following template:
+
+				<!-- IF condition -->
+				some content
+				<!-- ENDIF -->
+
+			If we were to simply preserve all whitespace, we could simply replace all "?>" tags
+			with "?>\n".
+			Doing that, would add additional newlines to the compiled tempalte in place of the
+			IF and ENDIF statements. These newlines are unwanted (and one is conditional).
+			The IF and ENDIF are usually on their own line for ease of reading.
+
+			This replacement preserves newlines only for statements that aren't the only statement on a line.
+			It will NOT preserve newlines at the end of statements in the above examle.
+			It will preserve newlines in situations like:
+
+				<!-- IF condition -->inline content<!-- ENDIF -->
+
+
+		*/
+
+		$data = preg_replace('~(?<!^)(<\?php(?:(?<!\?>).)+(?<!/\*\*/)\?>)$~m', "$1\n", $data);
+		$data = str_replace('/**/?>', "?>\n", $data);
+		$data = str_replace('?><?php', '', $data);
+		return $data;
+	}
+
+	/**
+	* Prepends a preamble to compiled template.
+	* Currently preamble checks if IN_PHPBB is defined and calls exit() if it is not.
+	*
+	* @param string $data Compiled template chunk
+	* @return string Compiled template chunk with preamble prepended
+	*/
+	private function prepend_preamble($data)
+	{
+		$data = "<?php if (!defined('IN_PHPBB')) exit;" . ((strncmp($data, '<?php', 5) === 0) ? substr($data, 5) : ' ?>' . $data);
+		return $data;
+	}
+
+	/**
+	* Callback for replacing matched tokens with PHP code
+	*
+	* @param array $matches Regular expression matches
+	* @return string compiled template code
+	*/
+	private function replace($matches)
+	{
+		if ($this->in_php && $matches[1] != 'ENDPHP')
+		{
+			return '';
+		}
+
+		if (isset($matches[3]))
+		{
+			return $this->compile_var_tags($matches[0]);
+		}
+
+		switch ($matches[1])
+		{
+			case 'BEGIN':
+				$this->block_else_level[] = false;
+				return '<?php ' . $this->compile_tag_block($matches[2]) . ' ?>';
+			break;
+
+			case 'BEGINELSE':
+				$this->block_else_level[sizeof($this->block_else_level) - 1] = true;
+				return '<?php }} else { ?>';
+			break;
+
+			case 'END':
+				array_pop($this->block_names);
+				return '<?php ' . ((array_pop($this->block_else_level)) ? '}' : '}}') . ' ?>';
+			break;
+
+			case 'IF':
+				return '<?php ' . $this->compile_tag_if($matches[2], false) . ' ?>';
+			break;
+
+			case 'ELSE':
+				return '<?php } else { ?>';
+			break;
+
+			case 'ELSEIF':
+				return '<?php ' . $this->compile_tag_if($matches[2], true) . ' ?>';
+			break;
+
+			case 'ENDIF':
+				return '<?php } ?>';
+			break;
+
+			case 'DEFINE':
+				return '<?php ' . $this->compile_tag_define($matches[2], true) . ' ?>';
+			break;
+
+			case 'UNDEFINE':
+				return '<?php ' . $this->compile_tag_define($matches[2], false) . ' ?>';
+			break;
+
+			case 'INCLUDE':
+				return '<?php ' . $this->compile_tag_include($matches[2]) . ' ?>';
+			break;
+
+			case 'INCLUDEPHP':
+				return ($this->allow_php) ? '<?php ' . $this->compile_tag_include_php($matches[2]) . ' ?>' : '';
+			break;
+
+			case 'PHP':
+				if ($this->allow_php)
+				{
+					$this->in_php = true;
+					return '<?php ';
+				}
+				return '<!-- PHP -->';
+			break;
+
+			case 'ENDPHP':
+				if ($this->allow_php)
+				{
+					$this->in_php = false;
+					return ' ?>';
+				}
+				return '<!-- ENDPHP -->';
+			break;
+
+			default:
+				return $matches[0];
+			break;
+
+		}
+		return '';
+	}
+
+	/**
+	* Compile variables
+	*
+	* @param string $text_blocks Variable reference in source template
+	* @return string compiled template code
+	*/
+	private function compile_var_tags(&$text_blocks)
+	{
+		// change template varrefs into PHP varrefs
+		$varrefs = array();
+
+		// This one will handle varrefs WITH namespaces
+		preg_match_all('#\{((?:' . self::REGEX_NS . '\.)+)(\$)?(' . self::REGEX_VAR . ')\}#', $text_blocks, $varrefs, PREG_SET_ORDER);
+
+		foreach ($varrefs as $var_val)
+		{
+			$namespace = $var_val[1];
+			$varname = $var_val[3];
+			$new = $this->generate_block_varref($namespace, $varname, true, $var_val[2]);
+
+			$text_blocks = str_replace($var_val[0], $new, $text_blocks);
+		}
+
+		// Handle special language tags L_ and LA_
+		$this->compile_language_tags($text_blocks);
+
+		// This will handle the remaining root-level varrefs
+		$text_blocks = preg_replace('#\{(' . self::REGEX_VAR . ')\}#', "<?php echo (isset(\$_rootref['\\1'])) ? \$_rootref['\\1'] : ''; /**/?>", $text_blocks);
+		$text_blocks = preg_replace('#\{\$(' . self::REGEX_VAR . ')\}#', "<?php echo (isset(\$_tpldata['DEFINE']['.']['\\1'])) ? \$_tpldata['DEFINE']['.']['\\1'] : ''; /**/?>", $text_blocks);
+
+		return $text_blocks;
+	}
+
+	/**
+	* Handles special language tags L_ and LA_
+	*
+	* @param string $text_blocks Variable reference in source template
+	*/
+	private function compile_language_tags(&$text_blocks)
+	{
+		// transform vars prefixed by L_ into their language variable pendant if nothing is set within the tpldata array
+		if (strpos($text_blocks, '{L_') !== false)
+		{
+			$text_blocks = preg_replace('#\{L_(' . self::REGEX_VAR . ')\}#', "<?php echo ((isset(\$_rootref['L_\\1'])) ? \$_rootref['L_\\1'] : ((isset(\$_lang['\\1'])) ? \$_lang['\\1'] : '{ \\1 }')); /**/?>", $text_blocks);
+		}
+
+		// Handle addslashed language variables prefixed with LA_
+		// If a template variable already exist, it will be used in favor of it...
+		if (strpos($text_blocks, '{LA_') !== false)
+		{
+			$text_blocks = preg_replace('#\{LA_(' . self::REGEX_VAR . '+)\}#', "<?php echo ((isset(\$_rootref['LA_\\1'])) ? \$_rootref['LA_\\1'] : ((isset(\$_rootref['L_\\1'])) ? addslashes(\$_rootref['L_\\1']) : ((isset(\$_lang['\\1'])) ? addslashes(\$_lang['\\1']) : '{ \\1 }'))); /**/?>", $text_blocks);
+		}
+	}
+
+	/**
+	* Compile blocks
+	*
+	* @param string $tag_args Block contents in source template
+	* @return string compiled template code
+	*/
+	private function compile_tag_block($tag_args)
+	{
+		$no_nesting = false;
+
+		// Is the designer wanting to call another loop in a loop?
+		// <!-- BEGIN loop -->
+		// <!-- BEGIN !loop2 -->
+		// <!-- END !loop2 -->
+		// <!-- END loop -->
+		// 'loop2' is actually on the same nesting level as 'loop' you assign
+		// variables to it with template->assign_block_vars('loop2', array(...))
+		if (strpos($tag_args, '!') === 0)
+		{
+			// Count the number if ! occurrences (not allowed in vars)
+			$no_nesting = substr_count($tag_args, '!');
+			$tag_args = substr($tag_args, $no_nesting);
+		}
+
+		// Allow for control of looping (indexes start from zero):
+		// foo(2)    : Will start the loop on the 3rd entry
+		// foo(-2)   : Will start the loop two entries from the end
+		// foo(3,4)  : Will start the loop on the fourth entry and end it on the fifth
+		// foo(3,-4) : Will start the loop on the fourth entry and end it four from last
+		$match = array();
+
+		if (preg_match('#^([^()]*)\(([\-\d]+)(?:,([\-\d]+))?\)$#', $tag_args, $match))
+		{
+			$tag_args = $match[1];
+
+			if ($match[2] < 0)
+			{
+				$loop_start = '($_' . $tag_args . '_count ' . $match[2] . ' < 0 ? 0 : $_' . $tag_args . '_count ' . $match[2] . ')';
+			}
+			else
+			{
+				$loop_start = '($_' . $tag_args . '_count < ' . $match[2] . ' ? $_' . $tag_args . '_count : ' . $match[2] . ')';
+			}
+
+			if (!isset($match[3]) || strlen($match[3]) < 1 || $match[3] == -1)
+			{
+				$loop_end = '$_' . $tag_args . '_count';
+			}
+			else if ($match[3] >= 0)
+			{
+				$loop_end = '(' . ($match[3] + 1) . ' > $_' . $tag_args . '_count ? $_' . $tag_args . '_count : ' . ($match[3] + 1) . ')';
+			}
+			else //if ($match[3] < -1)
+			{
+				$loop_end = '$_' . $tag_args . '_count' . ($match[3] + 1);
+			}
+		}
+		else
+		{
+			$loop_start = 0;
+			$loop_end = '$_' . $tag_args . '_count';
+		}
+
+		$tag_template_php = '';
+		array_push($this->block_names, $tag_args);
+
+		if ($no_nesting !== false)
+		{
+			// We need to implode $no_nesting times from the end...
+			$block = array_slice($this->block_names, -$no_nesting);
+		}
+		else
+		{
+			$block = $this->block_names;
+		}
+
+		if (sizeof($block) < 2)
+		{
+			// Block is not nested.
+			$tag_template_php = '$_' . $tag_args . "_count = (isset(\$_tpldata['$tag_args'])) ? sizeof(\$_tpldata['$tag_args']) : 0;";
+			$varref = "\$_tpldata['$tag_args']";
+		}
+		else
+		{
+			// This block is nested.
+			// Generate a namespace string for this block.
+			$namespace = implode('.', $block);
+
+			// Get a reference to the data array for this block that depends on the
+			// current indices of all parent blocks.
+			$varref = $this->generate_block_data_ref($namespace, false);
+
+			// Create the for loop code to iterate over this block.
+			$tag_template_php = '$_' . $tag_args . '_count = (isset(' . $varref . ')) ? sizeof(' . $varref . ') : 0;';
+		}
+
+		$tag_template_php .= 'if ($_' . $tag_args . '_count) {';
+
+		/**
+		* The following uses foreach for iteration instead of a for loop, foreach is faster but requires PHP to make a copy of the contents of the array which uses more memory
+		* <code>
+		*	if (!$offset)
+		*	{
+		*		$tag_template_php .= 'foreach (' . $varref . ' as $_' . $tag_args . '_i => $_' . $tag_args . '_val){';
+		*	}
+		* </code>
+		*/
+
+		$tag_template_php .= 'for ($_' . $tag_args . '_i = ' . $loop_start . '; $_' . $tag_args . '_i < ' . $loop_end . '; ++$_' . $tag_args . '_i){';
+		$tag_template_php .= '$_' . $tag_args . '_val = &' . $varref . '[$_' . $tag_args . '_i];';
+
+		return $tag_template_php;
+	}
+
+	/**
+	* Compile a general expression - much of this is from Smarty with
+	* some adaptions for our block level methods
+	*
+	* @param string $tag_args Expression (tag arguments) in source template
+	* @return string compiled template code
+	*/
+	private function compile_expression($tag_args)
+	{
+		$match = array();
+		preg_match_all('/(?:
+			"[^"\\\\]*(?:\\\\.[^"\\\\]*)*"         |
+			\'[^\'\\\\]*(?:\\\\.[^\'\\\\]*)*\'     |
+			[(),]                                  |
+			[^\s(),]+)/x', $tag_args, $match);
+
+		$tokens = $match[0];
+		$is_arg_stack = array();
+
+		for ($i = 0, $size = sizeof($tokens); $i < $size; $i++)
+		{
+			$token = &$tokens[$i];
+
+			switch ($token)
+			{
+				case '!==':
+				case '===':
+				case '<<':
+				case '>>':
+				case '|':
+				case '^':
+				case '&':
+				case '~':
+				case ')':
+				case ',':
+				case '+':
+				case '-':
+				case '*':
+				case '/':
+				case '@':
+				break;
+
+				case '==':
+				case 'eq':
+					$token = '==';
+				break;
+
+				case '!=':
+				case '<>':
+				case 'ne':
+				case 'neq':
+					$token = '!=';
+				break;
+
+				case '<':
+				case 'lt':
+					$token = '<';
+				break;
+
+				case '<=':
+				case 'le':
+				case 'lte':
+					$token = '<=';
+				break;
+
+				case '>':
+				case 'gt':
+					$token = '>';
+				break;
+
+				case '>=':
+				case 'ge':
+				case 'gte':
+					$token = '>=';
+				break;
+
+				case '&&':
+				case 'and':
+					$token = '&&';
+				break;
+
+				case '||':
+				case 'or':
+					$token = '||';
+				break;
+
+				case '!':
+				case 'not':
+					$token = '!';
+				break;
+
+				case '%':
+				case 'mod':
+					$token = '%';
+				break;
+
+				case '(':
+					array_push($is_arg_stack, $i);
+				break;
+
+				case 'is':
+					$is_arg_start = ($tokens[$i-1] == ')') ? array_pop($is_arg_stack) : $i-1;
+					$is_arg = implode(' ', array_slice($tokens, $is_arg_start, $i - $is_arg_start));
+
+					$new_tokens = $this->_parse_is_expr($is_arg, array_slice($tokens, $i+1));
+
+					array_splice($tokens, $is_arg_start, sizeof($tokens), $new_tokens);
+
+					$i = $is_arg_start;
+
+				// no break
+
+				default:
+					$varrefs = array();
+					if (preg_match('#^((?:' . self::REGEX_NS . '\.)+)?(\$)?(?=[A-Z])([A-Z0-9\-_]+)#s', $token, $varrefs))
+					{
+						if (!empty($varrefs[1]))
+						{
+							$namespace = substr($varrefs[1], 0, -1);
+							$dot_pos = strrchr($namespace, '.');
+							if ($dot_pos !== false)
+							{
+								$namespace = substr($dot_pos, 1);
+							}
+
+							// S_ROW_COUNT is deceptive, it returns the current row number not the number of rows
+							// hence S_ROW_COUNT is deprecated in favour of S_ROW_NUM
+							switch ($varrefs[3])
+							{
+								case 'S_ROW_NUM':
+								case 'S_ROW_COUNT':
+									$token = "\$_${namespace}_i";
+								break;
+
+								case 'S_NUM_ROWS':
+									$token = "\$_${namespace}_count";
+								break;
+
+								case 'S_FIRST_ROW':
+									$token = "(\$_${namespace}_i == 0)";
+								break;
+
+								case 'S_LAST_ROW':
+									$token = "(\$_${namespace}_i == \$_${namespace}_count - 1)";
+								break;
+
+								case 'S_BLOCK_NAME':
+									$token = "'$namespace'";
+								break;
+
+								default:
+									$token = $this->generate_block_data_ref(substr($varrefs[1], 0, -1), true, $varrefs[2]) . '[\'' . $varrefs[3] . '\']';
+									$token = '(isset(' . $token . ') ? ' . $token . ' : null)';
+								break;
+							}
+						}
+						else
+						{
+							$token = ($varrefs[2]) ? '$_tpldata[\'DEFINE\'][\'.\'][\'' . $varrefs[3] . '\']' : '$_rootref[\'' . $varrefs[3] . '\']';
+							$token = '(isset(' . $token . ') ? ' . $token . ' : null)';
+						}
+
+					}
+					else if (preg_match('#^\.((?:' . self::REGEX_NS . '\.?)+)$#s', $token, $varrefs))
+					{
+						// Allow checking if loops are set with .loopname
+						// It is also possible to check the loop count by doing <!-- IF .loopname > 1 --> for example
+						$blocks = explode('.', $varrefs[1]);
+
+						// If the block is nested, we have a reference that we can grab.
+						// If the block is not nested, we just go and grab the block from _tpldata
+						if (sizeof($blocks) > 1)
+						{
+							$block = array_pop($blocks);
+							$namespace = implode('.', $blocks);
+							$varref = $this->generate_block_data_ref($namespace, true);
+
+							// Add the block reference for the last child.
+							$varref .= "['" . $block . "']";
+						}
+						else
+						{
+							$varref = '$_tpldata';
+
+							// Add the block reference for the last child.
+							$varref .= "['" . $blocks[0] . "']";
+						}
+						$token = "(isset($varref) ? sizeof($varref) : 0)";
+					}
+
+				break;
+			}
+		}
+
+		return $tokens;
+	}
+
+	/**
+	* Compile IF tags
+	*
+	* @param string $tag_args Expression given with IF in source template
+	* @param bool $elseif True if compiling an IF tag, false if compiling an ELSEIF tag
+	* @return string compiled template code
+	*/
+	private function compile_tag_if($tag_args, $elseif)
+	{
+		$tokens = $this->compile_expression($tag_args);
+
+		$tpl = ($elseif) ? '} else if (' : 'if (';
+
+		$tpl .= implode(' ', $tokens);
+		$tpl .= ') { ';
+
+		return $tpl;
+	}
+
+	/**
+	* Compile DEFINE tags
+	*
+	* @param string $tag_args Expression given with DEFINE in source template
+	* @param bool $op True if compiling a DEFINE tag, false if compiling an UNDEFINE tag
+	* @return string compiled template code
+	*/
+	private function compile_tag_define($tag_args, $op)
+	{
+		$match = array();
+		preg_match('#^((?:' . self::REGEX_NS . '\.)+)?\$(?=[A-Z])([A-Z0-9_\-]*)(?: = (.*?))?$#', $tag_args, $match);
+
+		if (empty($match[2]) || (!isset($match[3]) && $op))
+		{
+			return '';
+		}
+
+		if (!$op)
+		{
+			return 'unset(' . (($match[1]) ? $this->generate_block_data_ref(substr($match[1], 0, -1), true, true) . '[\'' . $match[2] . '\']' : '$_tpldata[\'DEFINE\'][\'.\'][\'' . $match[2] . '\']') . ');';
+		}
+
+		$parsed_statement = implode(' ', $this->compile_expression($match[3]));
+
+		return (($match[1]) ? $this->generate_block_data_ref(substr($match[1], 0, -1), true, true) . '[\'' . $match[2] . '\']' : '$_tpldata[\'DEFINE\'][\'.\'][\'' . $match[2] . '\']') . ' = ' . $parsed_statement . ';';
+	}
+
+	/**
+	* Compile INCLUDE tag
+	*
+	* @param string $tag_args Expression given with INCLUDE in source template
+	* @return string compiled template code
+	*/
+	private function compile_tag_include($tag_args)
+	{
+		return "\$_template->_tpl_include('$tag_args');";
+	}
+
+	/**
+	* Compile INCLUDE_PHP tag
+	*
+	* @param string $tag_args Expression given with INCLUDEPHP in source template
+	* @return string compiled template code
+	*/
+	private function compile_tag_include_php($tag_args)
+	{
+		return "\$_template->_php_include('$tag_args');";
+	}
+
+	/**
+	* parse expression
+	* This is from Smarty
+	*/
+	private function _parse_is_expr($is_arg, $tokens)
+	{
+		$expr_end = 0;
+		$negate_expr = false;
+
+		if (($first_token = array_shift($tokens)) == 'not')
+		{
+			$negate_expr = true;
+			$expr_type = array_shift($tokens);
+		}
+		else
+		{
+			$expr_type = $first_token;
+		}
+
+		switch ($expr_type)
+		{
+			case 'even':
+				if (isset($tokens[$expr_end]) && $tokens[$expr_end] == 'by')
+				{
+					$expr_end++;
+					$expr_arg = $tokens[$expr_end++];
+					$expr = "!(($is_arg / $expr_arg) & 1)";
+				}
+				else
+				{
+					$expr = "!($is_arg & 1)";
+				}
+			break;
+
+			case 'odd':
+				if (isset($tokens[$expr_end]) && $tokens[$expr_end] == 'by')
+				{
+					$expr_end++;
+					$expr_arg = $tokens[$expr_end++];
+					$expr = "(($is_arg / $expr_arg) & 1)";
+				}
+				else
+				{
+					$expr = "($is_arg & 1)";
+				}
+			break;
+
+			case 'div':
+				if (isset($tokens[$expr_end]) && $tokens[$expr_end] == 'by')
+				{
+					$expr_end++;
+					$expr_arg = $tokens[$expr_end++];
+					$expr = "!($is_arg % $expr_arg)";
+				}
+			break;
+		}
+
+		if ($negate_expr)
+		{
+			if ($expr[0] == '!')
+			{
+				// Negated expression, de-negate it.
+				$expr = substr($expr, 1);
+			}
+			else
+			{
+				$expr = "!($expr)";
+			}
+		}
+
+		array_splice($tokens, 0, $expr_end, $expr);
+
+		return $tokens;
+	}
+
+	/**
+	* Generates a reference to the given variable inside the given (possibly nested)
+	* block namespace. This is a string of the form:
+	* ' . $_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['varname'] . '
+	* It's ready to be inserted into an "echo" line in one of the templates.
+	*
+	* @param string $namespace Namespace to access (expects a trailing "." on the namespace)
+	* @param string $varname Variable name to use
+	* @param bool $echo If true return an echo statement, otherwise a reference to the internal variable
+	* @param bool $defop If true this is a variable created with the DEFINE construct, otherwise template variable
+	* @return string Code to access variable or echo it if $echo is true
+	*/
+	private function generate_block_varref($namespace, $varname, $echo = true, $defop = false)
+	{
+		// Strip the trailing period.
+		$namespace = substr($namespace, 0, -1);
+
+		$expr = true;
+		$isset = false;
+
+		// S_ROW_COUNT is deceptive, it returns the current row number now the number of rows
+		// hence S_ROW_COUNT is deprecated in favour of S_ROW_NUM
+		switch ($varname)
+		{
+			case 'S_ROW_NUM':
+			case 'S_ROW_COUNT':
+				$varref = "\$_${namespace}_i";
+			break;
+
+			case 'S_NUM_ROWS':
+				$varref = "\$_${namespace}_count";
+			break;
+
+			case 'S_FIRST_ROW':
+				$varref = "(\$_${namespace}_i == 0)";
+			break;
+
+			case 'S_LAST_ROW':
+				$varref = "(\$_${namespace}_i == \$_${namespace}_count - 1)";
+			break;
+
+			case 'S_BLOCK_NAME':
+				$varref = "'$namespace'";
+			break;
+
+			default:
+				// Get a reference to the data block for this namespace.
+				$varref = $this->generate_block_data_ref($namespace, true, $defop);
+				// Prepend the necessary code to stick this in an echo line.
+
+				// Append the variable reference.
+				$varref .= "['$varname']";
+
+				$expr = false;
+				$isset = true;
+			break;
+		}
+		// @todo Test the !$expr more
+		$varref = ($echo) ? '<?php echo ' . ($isset ? "isset($varref) ? $varref : ''" : $varref) . '; /**/?>' : (($expr || isset($varref)) ? $varref : '');
+
+		return $varref;
+	}
+
+	/**
+	* Generates a reference to the array of data values for the given
+	* (possibly nested) block namespace. This is a string of the form:
+	* $_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['$childN']
+	*
+	* @param string $blockname Block to access (does not expect a trailing "." on the blockname)
+	* @param bool $include_last_iterator If $include_last_iterator is true, then [$_childN_i] will be appended to the form shown above.
+	* @param bool $defop If true this is a variable created with the DEFINE construct, otherwise template variable
+	* @return string Code to access variable
+	*/
+	private function generate_block_data_ref($blockname, $include_last_iterator, $defop = false)
+	{
+		// Get an array of the blocks involved.
+		$blocks = explode('.', $blockname);
+		$blockcount = sizeof($blocks) - 1;
+
+		// DEFINE is not an element of any referenced variable, we must use _tpldata to access it
+		if ($defop)
+		{
+			$varref = '$_tpldata[\'DEFINE\']';
+			// Build up the string with everything but the last child.
+			for ($i = 0; $i < $blockcount; $i++)
+			{
+				$varref .= "['" . $blocks[$i] . "'][\$_" . $blocks[$i] . '_i]';
+			}
+			// Add the block reference for the last child.
+			$varref .= "['" . $blocks[$blockcount] . "']";
+			// Add the iterator for the last child if requried.
+			if ($include_last_iterator)
+			{
+				$varref .= '[$_' . $blocks[$blockcount] . '_i]';
+			}
+			return $varref;
+		}
+		else if ($include_last_iterator)
+		{
+			return '$_'. $blocks[$blockcount] . '_val';
+		}
+		else
+		{
+			return '$_'. $blocks[$blockcount - 1] . '_val[\''. $blocks[$blockcount]. '\']';
+		}
+	}
+}
diff --git a/phpBB/includes/template/locator.php b/phpBB/includes/template/locator.php
new file mode 100644
index 0000000000..35e33bb9e6
--- /dev/null
+++ b/phpBB/includes/template/locator.php
@@ -0,0 +1,211 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2011 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+
+/**
+* Template locator. Maintains mapping from template handles to source paths.
+*
+* Template locator is aware of template inheritance, and can return actual
+* filesystem paths (i.e., the "primary" template or the "parent" template)
+* depending on what files exist.
+*
+* @package phpBB3
+*/
+class phpbb_template_locator
+{
+	/**
+	* @var string Path to directory that templates are stored in.
+	*/
+	private $root = '';
+
+	/**
+	* @var string Path to parent/fallback template directory.
+	*/
+	private $inherit_root = '';
+
+	/**
+	* @var array Map from handles to source template file paths.
+	* Normally it only contains paths for handles that are used
+	* (or are likely to be used) by the page being rendered and not
+	* all templates that exist on the filesystem.
+	*/
+	private $files = array();
+
+	/**
+	* @var array Map from handles to source template file names.
+	* Covers the same data as $files property but maps to basenames
+	* instead of paths.
+	*/
+	private $filenames = array();
+
+	/**
+	* @var array Map from handles to parent/fallback source template
+	* file paths. Covers the same data as $files.
+	*/
+	private $files_inherit = array();
+
+	/**
+	* Set custom template location (able to use directory outside of phpBB).
+	*
+	* Note: Templates are still compiled to phpBB's cache directory.
+	*
+	* @param string $template_path Path to template directory
+	* @param string|bool $fallback_template_path Path to fallback template, or false to disable fallback
+	*/
+	public function set_custom_template($template_path, $fallback_template_path = false)
+	{
+		// Make sure $template_path has no ending slash
+		if (substr($template_path, -1) == '/')
+		{
+			$template_path = substr($template_path, 0, -1);
+		}
+
+		$this->root = $template_path;
+
+		if ($fallback_template_path !== false)
+		{
+			if (substr($fallback_template_path, -1) == '/')
+			{
+				$fallback_template_path = substr($fallback_template_path, 0, -1);
+			}
+
+			$this->inherit_root = $fallback_template_path;
+		}
+	}
+
+	/**
+	* Sets the template filenames for handles. $filename_array
+	* should be a hash of handle => filename pairs.
+	*
+	* @param array $filname_array Should be a hash of handle => filename pairs.
+	*/
+	public function set_filenames(array $filename_array)
+	{
+		foreach ($filename_array as $handle => $filename)
+		{
+			if (empty($filename))
+			{
+				trigger_error("template locator: set_filenames: Empty filename specified for $handle", E_USER_ERROR);
+			}
+
+			$this->filename[$handle] = $filename;
+			$this->files[$handle] = $this->root . '/' . $filename;
+
+			if ($this->inherit_root)
+			{
+				$this->files_inherit[$handle] = $this->inherit_root . '/' . $filename;
+			}
+		}
+	}
+
+	/**
+	* Determines the filename for a template handle.
+	*
+	* The filename comes from array used in a set_filenames call,
+	* which should have been performed prior to invoking this function.
+	* Return value is a file basename (without path).
+	*
+	* @param $handle string Template handle
+	* @return string Filename corresponding to the template handle
+	*/
+	public function get_filename_for_handle($handle)
+	{
+		if (!isset($this->filename[$handle]))
+		{
+			trigger_error("template locator: get_filename_for_handle: No file specified for handle $handle", E_USER_ERROR);
+		}
+		return $this->filename[$handle];
+	}
+
+	/**
+	* Determines the source file path for a template handle without
+	* regard for template inheritance.
+	*
+	* This function returns the path in "primary" template directory
+	* corresponding to the given template handle. That path may or
+	* may not actually exist on the filesystem. Because this function
+	* does not perform stat calls to determine whether the path it
+	* returns actually exists, it is faster than get_source_file_for_handle.
+	*
+	* Use get_source_file_for_handle to obtain the actual path that is
+	* guaranteed to exist (which might come from the parent/fallback
+	* template directory if template inheritance is used).
+	*
+	* This function will trigger an error if the handle was never
+	* associated with a template file via set_filenames.
+	*
+	* @param $handle string Template handle
+	* @return string Path to source file path in primary template directory
+	*/
+	public function get_virtual_source_file_for_handle($handle)
+	{
+		// If we don't have a file assigned to this handle, die.
+		if (!isset($this->files[$handle]))
+		{
+			trigger_error("template locator: No file specified for handle $handle", E_USER_ERROR);
+		}
+
+		$source_file = $this->files[$handle];
+		return $source_file;
+	}
+
+	/**
+	* Determines the source file path for a template handle, accounting
+	* for template inheritance and verifying that the path exists.
+	*
+	* This function returns the actual path that may be compiled for
+	* the specified template handle. It will trigger an error if
+	* the template handle was never associated with a template path
+	* via set_filenames or if the template file does not exist on the
+	* filesystem.
+	*
+	* Use get_virtual_source_file_for_handle to just resolve a template
+	* handle to a path without any filesystem or inheritance checks.
+	*
+	* @param string $handle Template handle (i.e. "friendly" template name)
+	* @return string Source file path
+	*/
+	public function get_source_file_for_handle($handle)
+	{
+		// If we don't have a file assigned to this handle, die.
+		if (!isset($this->files[$handle]))
+		{
+			trigger_error("template locator: No file specified for handle $handle", E_USER_ERROR);
+		}
+
+		$source_file = $this->files[$handle];
+
+		// Try and open template for reading
+		if (!file_exists($source_file))
+		{
+			if (isset($this->files_inherit[$handle]) && $this->files_inherit[$handle])
+			{
+				$parent_source_file = $this->files_inherit[$handle];
+				if (!file_exists($parent_source_file))
+				{
+					trigger_error("template locator: Neither $source_file nor $parent_source_file exist", E_USER_ERROR);
+				}
+				$source_file = $parent_source_file;
+			}
+			else
+			{
+				trigger_error("template locator: File $source_file does not exist", E_USER_ERROR);
+			}
+		}
+		return $source_file;
+	}
+}
diff --git a/phpBB/includes/template/renderer.php b/phpBB/includes/template/renderer.php
new file mode 100644
index 0000000000..59c85df443
--- /dev/null
+++ b/phpBB/includes/template/renderer.php
@@ -0,0 +1,35 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2011 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+* Template renderer interface.
+*
+* Objects implementing this interface encapsulate a means of displaying
+* a template.
+*
+* @package phpBB3
+*/
+interface phpbb_template_renderer
+{
+	/**
+	* Displays the template managed by this renderer.
+	*
+	* @param phpbb_template_context $context Template context to use
+	* @param array $lang Language entries to use
+	*/
+	public function render($context, $lang);
+}
diff --git a/phpBB/includes/template/renderer_eval.php b/phpBB/includes/template/renderer_eval.php
new file mode 100644
index 0000000000..11e2a30f06
--- /dev/null
+++ b/phpBB/includes/template/renderer_eval.php
@@ -0,0 +1,60 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2011 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+* Template renderer that stores compiled template's php code and
+* displays it via eval.
+*
+* @package phpBB3
+*/
+class phpbb_template_renderer_eval implements phpbb_template_renderer
+{
+	/**
+	* Template code to be eval'ed.
+	*/
+	private $code;
+
+	/**
+	* Constructor. Stores provided code for future evaluation.
+	* Template includes are delegated to template object $template.
+	*
+	* @param string $code php code of the template
+	* @param phpbb_template $template template object
+	*/
+	public function __construct($code, $template)
+	{
+		$this->code = $code;
+		$this->template = $template;
+	}
+
+	/**
+	* Displays the template managed by this renderer by eval'ing php code
+	* of the template.
+	*
+	* @param phpbb_template_context $context Template context to use
+	* @param array $lang Language entries to use
+	*/
+	public function render($context, $lang)
+	{
+		$_template = $this->template;
+		$_tpldata = &$context->get_data_ref();
+		$_rootref = &$context->get_root_ref();
+		$_lang = $lang;
+
+		eval($this->code);
+	}
+}
diff --git a/phpBB/includes/template/renderer_include.php b/phpBB/includes/template/renderer_include.php
new file mode 100644
index 0000000000..40e7a3376c
--- /dev/null
+++ b/phpBB/includes/template/renderer_include.php
@@ -0,0 +1,60 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2011 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+
+/**
+* Template renderer that stores path to php file with template code
+* and displays it by including the file.
+*
+* @package phpBB3
+*/
+class phpbb_template_renderer_include implements phpbb_template_renderer
+{
+	/**
+	* Template path to be included.
+	*/
+	private $path;
+
+	/**
+	* Constructor. Stores path to the template for future inclusion.
+	* Template includes are delegated to template object $template.
+	*
+	* @param string $path path to the template
+	*/
+	public function __construct($path, $template)
+	{
+		$this->path = $path;
+		$this->template = $template;
+	}
+
+	/**
+	* Displays the template managed by this renderer by including
+	* the php file containing the template.
+	*
+	* @param phpbb_template_context $context Template context to use
+	* @param array $lang Language entries to use
+	*/
+	public function render($context, $lang)
+	{
+		$_template = $this->template;
+		$_tpldata = &$context->get_data_ref();
+		$_rootref = &$context->get_root_ref();
+		$_lang = $lang;
+
+		include($this->path);
+	}
+}
diff --git a/phpBB/includes/template/template.php b/phpBB/includes/template/template.php
new file mode 100644
index 0000000000..4007b77db8
--- /dev/null
+++ b/phpBB/includes/template/template.php
@@ -0,0 +1,491 @@
+<?php
+/**
+*
+* @package phpBB3
+* @copyright (c) 2005 phpBB Group, sections (c) 2001 ispi of Lincoln Inc
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+* @todo
+* IMG_ for image substitution?
+* {IMG_[key]:[alt]:[type]}
+* {IMG_ICON_CONTACT:CONTACT:full} -> $user->img('icon_contact', 'CONTACT', 'full');
+*
+* More in-depth...
+* yadayada
+*/
+
+/**
+* Base Template class.
+* @package phpBB3
+*/
+class phpbb_template
+{
+	/**
+	* @var phpbb_template_context Template context.
+	* Stores template data used during template rendering.
+	*/
+	private $context;
+
+	/**
+	* @var string Path of the cache directory for the template
+	*/
+	public $cachepath = '';
+
+	/**
+	* @var string phpBB root path
+	*/
+	private $phpbb_root_path;
+
+	/**
+	* @var phpEx PHP file extension
+	*/
+	private $phpEx;
+
+	/**
+	* @var phpbb_config phpBB config instance
+	*/
+	private $config;
+
+	/**
+	* @var user current user
+	*/
+	private $user;
+
+	/**
+	* @var locator template locator
+	*/
+	private $locator;
+
+	/**
+	* Constructor.
+	*
+	* @param string $phpbb_root_path phpBB root path
+	* @param user $user current user
+	* @param phpbb_template_locator $locator template locator
+	*/
+	public function __construct($phpbb_root_path, $phpEx, $config, $user, phpbb_template_locator $locator)
+	{
+		$this->phpbb_root_path = $phpbb_root_path;
+		$this->phpEx = $phpEx;
+		$this->config = $config;
+		$this->user = $user;
+		$this->locator = $locator;
+	}
+
+	/**
+	* Set template location based on (current) user's chosen style.
+	*/
+	public function set_template()
+	{
+		$style_name = $this->user->theme['template_path'];
+
+		$relative_template_root = $this->relative_template_root_for_style($style_name);
+		$template_root = $this->phpbb_root_path . $relative_template_root;
+		if (!file_exists($template_root))
+		{
+			trigger_error('template locator: Template path could not be found: ' . $relative_template_root, E_USER_ERROR);
+		}
+
+		if ($this->user->theme['template_inherits_id'])
+		{
+			$fallback_template_path = $this->phpbb_root_path . $this->relative_template_root_for_style($this->user->theme['template_inherit_path']);
+		}
+		else
+		{
+			$fallback_template_path = null;
+		}
+
+		return $this->set_custom_template($template_root, $style_name, $fallback_template_path);
+	}
+
+	/**
+	* Set custom template location (able to use directory outside of phpBB).
+	*
+	* Note: Templates are still compiled to phpBB's cache directory.
+	*
+	* @param string $template_path Path to template directory
+	* @param string $template_name Name of template
+	* @param string $fallback_template_path Path to fallback template
+	*/
+	public function set_custom_template($template_path, $style_name, $fallback_template_path = false)
+	{
+		$this->locator->set_custom_template($template_path, $fallback_template_path);
+
+		$this->cachepath = $this->phpbb_root_path . 'cache/ctpl_' . str_replace('_', '-', $style_name) . '_';
+
+		$this->context = new phpbb_template_context();
+
+		return true;
+	}
+
+	/**
+	* Converts a style name to relative (to board root) path to
+	* the style's template files.
+	*
+	* @param $style_name string Style name
+	* @return string Path to style template files
+	*/
+	private function relative_template_root_for_style($style_name)
+	{
+		return 'styles/' . $style_name . '/template';
+	}
+
+	/**
+	* Sets the template filenames for handles.
+	*
+	* @param array $filname_array Should be a hash of handle => filename pairs.
+	*/
+	public function set_filenames(array $filename_array)
+	{
+		$this->locator->set_filenames($filename_array);
+
+		return true;
+	}
+
+	/**
+	* Clears all variables and blocks assigned to this template.
+	*/
+	public function destroy()
+	{
+		$this->context->clear();
+	}
+
+	/**
+	* Reset/empty complete block
+	*
+	* @param string $blockname Name of block to destroy
+	*/
+	public function destroy_block_vars($blockname)
+	{
+		$this->context->destroy_block_vars($blockname);
+	}
+
+	/**
+	* Display a template for provided handle.
+	*
+	* The template will be loaded and compiled, if necessary, first.
+	*
+	* This function calls hooks.
+	*
+	* @param string $handle Handle to display
+	* @return bool True on success, false on failure
+	*/
+	public function display($handle)
+	{
+		$result = $this->call_hook($handle);
+		if ($result !== false)
+		{
+			return $result[0];
+		}
+
+		return $this->load_and_render($handle);
+	}
+
+	/**
+	* Loads a template for $handle, compiling it if necessary, and
+	* renders the template.
+	*
+	* @param string $handle Template handle to render
+	* @return bool True on success, false on failure
+	*/
+	private function load_and_render($handle)
+	{
+		$renderer = $this->_tpl_load($handle);
+
+		if ($renderer)
+		{
+			$renderer->render($this->context, $this->get_lang());
+			return true;
+		}
+		else
+		{
+			return false;
+		}
+	}
+
+	/**
+	* Calls hook if any is defined.
+	*
+	* @param string $handle Template handle being displayed.
+	*/
+	private function call_hook($handle)
+	{
+		global $phpbb_hook;
+
+		if (!empty($phpbb_hook) && $phpbb_hook->call_hook(array(__CLASS__, __FUNCTION__), $handle, $this))
+		{
+			if ($phpbb_hook->hook_return(array(__CLASS__, __FUNCTION__)))
+			{
+				$result = $phpbb_hook->hook_return_result(array(__CLASS__, __FUNCTION__));
+				return array($result);
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	* Obtains language array.
+	* This is either lang property of $user property, or if
+	* it is not set an empty array.
+	* @return array language entries
+	*/
+	public function get_lang()
+	{
+		if (isset($this->user->lang))
+		{
+			$lang = $this->user->lang;
+		}
+		else
+		{
+			$lang = array();
+		}
+		return $lang;
+	}
+
+	/**
+	* Display the handle and assign the output to a template variable
+	* or return the compiled result.
+	*
+	* @param string $handle Handle to operate on
+	* @param string $template_var Template variable to assign compiled handle to
+	* @param bool $return_content If true return compiled handle, otherwise assign to $template_var
+	* @return bool|string false on failure, otherwise if $return_content is true return string of the compiled handle, otherwise return true
+	*/
+	public function assign_display($handle, $template_var = '', $return_content = true)
+	{
+		ob_start();
+		$result = $this->display($handle);
+		$contents = ob_get_clean();
+		if ($result === false)
+		{
+			return false;
+		}
+
+		if ($return_content)
+		{
+			return $contents;
+		}
+
+		$this->assign_var($template_var, $contents);
+
+		return true;
+	}
+
+	/**
+	* Obtains a template renderer for a template identified by specified
+	* handle. The template renderer can display the template later.
+	*
+	* Template source will first be compiled into php code.
+	* If template cache is writable the compiled php code will be stored
+	* on filesystem and template will not be subsequently recompiled.
+	* If template cache is not writable template source will be recompiled
+	* every time it is needed. DEBUG_EXTRA define and load_tplcompile
+	* configuration setting may be used to force templates to be always
+	* recompiled.
+	*
+	* Returns an object implementing phpbb_template_renderer, or null
+	* if template loading or compilation failed. Call render() on the
+	* renderer to display the template. This will result in template
+	* contents sent to the output stream (unless, of course, output
+	* buffering is in effect).
+	*
+	* @param string $handle Handle of the template to load
+	* @return phpbb_template_renderer Template renderer object, or null on failure
+	* @uses template_compile is used to compile template source
+	*/
+	private function _tpl_load($handle)
+	{
+		$virtual_source_file = $this->locator->get_virtual_source_file_for_handle($handle);
+		$source_file = null;
+
+		$compiled_path = $this->cachepath . str_replace('/', '.', $virtual_source_file) . '.' . $this->phpEx;
+
+		$recompile = defined('DEBUG_EXTRA') ||
+			!file_exists($compiled_path) ||
+			@filesize($compiled_path) === 0 ||
+			($this->config['load_tplcompile'] && @filemtime($compiled_path) < @filemtime($source_file));
+
+		if (!$recompile && $this->config['load_tplcompile'])
+		{
+			$source_file = $this->locator->get_source_file_for_handle($handle);
+			$recompile = (@filemtime($compiled_path) < @filemtime($source_file)) ? true : false;
+		}
+
+		// Recompile page if the original template is newer, otherwise load the compiled version
+		if (!$recompile)
+		{
+			return new phpbb_template_renderer_include($compiled_path, $this);
+		}
+
+		if ($source_file === null)
+		{
+			$source_file = $this->locator->get_source_file_for_handle($handle);
+		}
+
+		$compile = new phpbb_template_compile($this->config['tpl_allow_php']);
+
+		$output_file = $this->_compiled_file_for_handle($handle);
+		if ($compile->compile_file_to_file($source_file, $output_file) !== false)
+		{
+			$renderer = new phpbb_template_renderer_include($output_file, $this);
+		}
+		else if (($code = $compile->compile_file($source_file)) !== false)
+		{
+			$renderer = new phpbb_template_renderer_eval($code, $this);
+		}
+		else
+		{
+			$renderer = null;
+		}
+
+		return $renderer;
+	}
+
+	/**
+	* Determines compiled file path for handle $handle.
+	*
+	* @param string $handle Template handle (i.e. "friendly" template name)
+	* @return string Compiled file path
+	*/
+	private function _compiled_file_for_handle($handle)
+	{
+		$source_file = $this->locator->get_filename_for_handle($handle);
+		$compiled_file = $this->cachepath . str_replace('/', '.', $source_file) . '.' . $this->phpEx;
+		return $compiled_file;
+	}
+
+	/**
+	* Assign key variable pairs from an array
+	*
+	* @param array $vararray A hash of variable name => value pairs
+	*/
+	public function assign_vars(array $vararray)
+	{
+		foreach ($vararray as $key => $val)
+		{
+			$this->assign_var($key, $val);
+		}
+	}
+
+	/**
+	* Assign a single variable to a single key
+	*
+	* @param string $varname Variable name
+	* @param string $varval Value to assign to variable
+	*/
+	public function assign_var($varname, $varval)
+	{
+		$this->context->assign_var($varname, $varval);
+	}
+
+	// Docstring is copied from phpbb_template_context method with the same name.
+	/**
+	* Assign key variable pairs from an array to a specified block
+	* @param string $blockname Name of block to assign $vararray to
+	* @param array $vararray A hash of variable name => value pairs
+	*/
+	public function assign_block_vars($blockname, array $vararray)
+	{
+		return $this->context->assign_block_vars($blockname, $vararray);
+	}
+
+	// Docstring is copied from phpbb_template_context method with the same name.
+	/**
+	* Change already assigned key variable pair (one-dimensional - single loop entry)
+	*
+	* An example of how to use this function:
+	* {@example alter_block_array.php}
+	*
+	* @param	string	$blockname	the blockname, for example 'loop'
+	* @param	array	$vararray	the var array to insert/add or merge
+	* @param	mixed	$key		Key to search for
+	*
+	* array: KEY => VALUE [the key/value pair to search for within the loop to determine the correct position]
+	*
+	* int: Position [the position to change or insert at directly given]
+	*
+	* If key is false the position is set to 0
+	* If key is true the position is set to the last entry
+	*
+	* @param	string	$mode		Mode to execute (valid modes are 'insert' and 'change')
+	*
+	*	If insert, the vararray is inserted at the given position (position counting from zero).
+	*	If change, the current block gets merged with the vararray (resulting in new key/value pairs be added and existing keys be replaced by the new value).
+	*
+	* Since counting begins by zero, inserting at the last position will result in this array: array(vararray, last positioned array)
+	* and inserting at position 1 will result in this array: array(first positioned array, vararray, following vars)
+	*
+	* @return bool false on error, true on success
+	*/
+	public function alter_block_array($blockname, array $vararray, $key = false, $mode = 'insert')
+	{
+		return $this->context->alter_block_array($blockname, $vararray, $key, $mode);
+	}
+
+	/**
+	* Include a separate template.
+	*
+	* This function is marked public due to the way the template
+	* implementation uses it. It is actually an implementation function
+	* and should not be considered part of template class's public API.
+	*
+	* @param string $filename Template filename to include
+	* @param bool $include True to include the file, false to just load it
+	* @uses template_compile is used to compile uncached templates
+	*/
+	public function _tpl_include($filename, $include = true)
+	{
+		$this->locator->set_filenames(array($filename => $filename));
+
+		if (!$this->load_and_render($filename))
+		{
+			// trigger_error cannot be used here, as the output already started
+			echo 'template->_tpl_include(): Failed including ' . htmlspecialchars($handle) . "\n";
+		}
+	}
+
+	/**
+	* Include a PHP file.
+	*
+	* If a relative path is passed in $filename, it is considered to be
+	* relative to board root ($phpbb_root_path). Absolute paths are
+	* also allowed.
+	*
+	* This function is marked public due to the way the template
+	* implementation uses it. It is actually an implementation function
+	* and should not be considered part of template class's public API.
+	*
+	* @param string $filename Path to PHP file to include
+	*/
+	public function _php_include($filename)
+	{
+		if (phpbb_is_absolute($filename))
+		{
+			$file = $filename;
+		}
+		else
+		{
+			$file = $this->phpbb_root_path . $filename;
+		}
+
+		if (!file_exists($file))
+		{
+			// trigger_error cannot be used here, as the output already started
+			echo 'template->_php_include(): File ' . htmlspecialchars($file) . " does not exist\n";
+			return;
+		}
+		include($file);
+	}
+}