Support for namespaced classes; added e_shims

e_shims is an e107 v2-compatible class for the first namespaced core
class, e107\Shims\All.

e107\Shims\All is built from the e107\Shims\InternalShims trait.

e107\Shims\InternalShims currently implements a resilient replacement
for the PHP internal readfile(), which is needed by issue #3528.

As for how the new namespaced classes are handled, the e107 class
(e107_handlers/e107_class.php) has an updated e107::autoload() which
detects namespaced classes and goes to e107::autoload_namespaced().

Namespaced classes handled by e107 are in the \e107 top-level namespace,
and all sub-levels match directory paths under e_HANDLER.

e107_handlers/Shims/InternalShims.php

@@ -0,0 +1,63 @@
+<?php
+/**
+ * e107 website system
+ *
+ * Copyright (C) 2008-2018 e107 Inc (e107.org)
+ * Released under the terms and conditions of the
+ * GNU General Public License (http://www.gnu.org/licenses/gpl.txt)
+ *
+ * Shims for PHP internal functions
+ */
+
+namespace e107\Shims;
+
+trait InternalShims
+{
+	/**
+	 * Outputs a file
+	 *
+	 * Resilient replacement for PHP internal readfile()
+	 *
+	 * @see https://github.com/e107inc/e107/issues/3528 Why this method was implemented
+	 * @param string $filename The filename being read.
+	 * @param bool $use_include_path You can use the optional second parameter and set it to TRUE,
+	 *                               if you want to search for the file in the include_path, too.
+	 * @param resource $context A context stream resource.
+	 * @return int|bool Returns the number of bytes read from the file.
+	 *                   If an error occurs, FALSE is returned.
+	 */
+	public static function readfile($filename, $use_include_path = FALSE, $context = NULL)
+	{
+		$output = @readfile($filename, $use_include_path, $context);
+		if ($output === NULL)
+		{
+			return self::readfile_alt($filename, $use_include_path, $context);
+		}
+		return $output;
+	}
+
+	/**
+	 * Outputs a file
+	 *
+	 * Alternative implementation using file streams
+	 *
+	 * @param $filename
+	 * @param bool $use_include_path
+	 * @param resource $context
+	 * @return bool|int
+	 */
+	public static function readfile_alt($filename, $use_include_path = FALSE, $context = NULL)
+	{
+		// fopen() silently returns false if there is no context
+		if (!is_resource($context)) $context = stream_context_create();
+
+		$handle = @fopen($filename, 'rb', $use_include_path, $context);
+		if ($handle === FALSE) return FALSE;
+		while (!feof($handle))
+		{
+			echo(fread($handle, 8192));
+		}
+		fclose($handle);
+		return filesize($filename);
+	}
+}

e107_handlers/Shims/e_shims.php

@@ -0,0 +1,31 @@
+<?php
+/**
+ * e107 website system
+ *
+ * Copyright (C) 2008-2018 e107 Inc (e107.org)
+ * Released under the terms and conditions of the
+ * GNU General Public License (http://www.gnu.org/licenses/gpl.txt)
+ *
+ * Shims for PHP internal functions
+ */
+
+namespace e107\Shims
+{
+	class All
+	{
+		use InternalShims;
+	}
+
+	class Internal
+	{
+		use InternalShims;
+	}
+}
+
+// e107 v2-style classes
+namespace
+{
+	class e_shims extends \e107\Shims\All
+	{
+	}
+}

e107_handlers/e107_class.php

@@ -203,6 +203,7 @@ class e107
 		'e_parse_shortcode'              => '{e_HANDLER}shortcode_handler.php',
 		'e_plugin'                       => '{e_HANDLER}plugin_class.php',
 		'e_ranks'                        => '{e_HANDLER}e_ranks_class.php',
+		'e_shims'                        => '{e_HANDLER}Shims/e_shims.php',
 		'e_shortcode'                    => '{e_HANDLER}shortcode_handler.php',
 		'e_system_user'                  => '{e_HANDLER}user_model.php',
 		'e_theme'                        => '{e_HANDLER}theme_handler.php',
@@ -4613,31 +4614,31 @@ class e107
 	{
 		$_data = self::getSession()->get('__sessionBrowserCache');
 		if(!is_array($_data)) $_data = array();
-		
+
 		if(null === $set)
 		{
 			return in_array(e_REQUEST_URI, $_data);
 		}
-		
+
 		// remove e_REQUEST_URI from the set
 		if(false === $set)
 		{
 			$check = array_search(e_REQUEST_URI, $_data);
-			if(false !== $check) 
+			if(false !== $check)
 			{
 				unset($_data[$check]);
 				self::getSession()->set('__sessionBrowserCache', $_data);
 				return;
 			}
 		}
-		
+
 		if(true === $set)
 		{
 			$set = e_REQUEST_URI;
 		}
-		
+
 		if(empty($set) || !is_string($set) || in_array($set, $_data)) return;
-		
+
 		$_data[]  = $set;
 		self::getSession()->set('__sessionBrowserCache', array_unique($_data));
 	}
@@ -4669,7 +4670,7 @@ class e107
 	 * If $do_return, will always return with ban status - TRUE for OK, FALSE for banned.
 	 * If return permitted, will never display a message for a banned user; otherwise will display any message then exit
 	 * FIXME - moved to ban helper, replace all calls
-	 * 
+	 *
 	 *
 	 * @param string $query
 	 * @param boolean $show_error
@@ -4720,11 +4721,11 @@ class e107
 	 * @param string $div divider
 	 * @return string encoded IP
 	 */
-	 
+
 	public function ipEncode($ip, $div = ':')
 	{
 		return self::getIPHandler()->ipEncode($ip);
-	} 
+	}
 
 	/**
 	 * Takes an encoded IP address - returns a displayable one
@@ -4833,14 +4834,14 @@ class e107
 		{
 			return spl_autoload_register($function);
 		}
-		
-		foreach ($registered as $r) 
+
+		foreach ($registered as $r)
 		{
 			spl_autoload_unregister($r);
 		}
-		
+
 		$result = spl_autoload_register($function);
-		foreach ($registered as $r) 
+		foreach ($registered as $r)
 		{
 			if(!spl_autoload_register($r)) $result = false;
 		}
@@ -4849,7 +4850,7 @@ class e107
 
 	/**
 	 * Former __autoload, generic core autoload logic
-	 * 
+	 *
 	 * Magic class autoload.
 	 * We are raising plugin structure standard here - plugin auto-loading works ONLY if
 	 * classes live inside 'includes' folder.
@@ -4886,6 +4887,14 @@ class e107
 		{
 	        return;
 	    }
+
+		// Detect namespaced class
+		if (strpos($className, '\\') !== false)
+		{
+			self::autoload_namespaced($className);
+			return;
+		}
+
 		$tmp = explode('_', $className);
 
 		//echo 'autoloding...'.$className.'<br />';
@@ -4894,7 +4903,7 @@ class e107
 			case 'plugin': // plugin handlers/shortcode batches
 				array_shift($tmp); // remove 'plugin'
 				$end = array_pop($tmp); // check for 'shortcodes' end phrase
-	
+
 				if (!isset($tmp[0]) || !$tmp[0])
 				{
 					if($end)
@@ -4905,7 +4914,7 @@ class e107
 					}
 					return; // In case we get an empty class part
 				}
-	
+
 				// Currently only batches inside shortcodes/ folder are auto-detected,
 				// read the todo for e_shortcode.php related problems
 				if('shortcodes' == $end)
@@ -4919,13 +4928,13 @@ class e107
 				{
 					$tmp[] = $end; // not a shortcode batch - append the end phrase again
 				}
-	
+
 				// Handler check
 				$tmp[0] .= '/includes'; //folder 'includes' is not part of the class name
 				$filename = e_PLUGIN.implode('/', $tmp).'.php';
 				//TODO add debug screen Auto-loaded classes - ['plugin: '.$filename.' - '.$className];
 			break;
-	
+
 			default: //core libraries, core shortcode batches
 				// core SC batch check
 				$end = array_pop($tmp);
@@ -4934,12 +4943,12 @@ class e107
 					$filename = e_CORE.'shortcodes/batch/'.$className.'.php'; // core shortcode batch
 					break;
 				}
-	
+
 				$filename = self::getHandlerPath($className, true);
 				//TODO add debug screen Auto-loaded classes - ['core: '.$filename.' - '.$className];
 			break;
 		}
-	
+
 		if(!empty($filename) && is_file($filename)) // Test with chatbox_menu
 		{
 			// autoload doesn't REQUIRE files, because this will break things like call_user_func()
@@ -4947,6 +4956,27 @@ class e107
 		}
 	}
 
+	/**
+	 * Autoloading logic for namespaced classes
+	 *
+	 * @param $className
+	 * @return void
+	 */
+	private static function autoload_namespaced($className)
+	{
+		$levels = explode('\\', $className);
+
+		// Guard against classes that are not ours
+		if ($levels[0] != 'e107') return;
+
+		$levels[0] = e_HANDLER;
+		$classPath = implode('/', $levels).'.php';
+		if (is_file($classPath) && is_readable($classPath))
+		{
+			include($classPath);
+		}
+	}
+
 	public function __get($name)
 	{
 		switch ($name)