:arrow_up: Update HTML Purifier library.

Updated HTML Purifier from 4.6.0 to 4.9.2 with better PHP7 compatibility.
Used composer to manage this library.

1 files changed, 292 insertions, 0 deletions

diff --git a/vendor/ezyang/htmlpurifier/library/HTMLPurifier.php b/vendor/ezyang/htmlpurifier/library/HTMLPurifier.php
new file mode 100644
index 000000000..9c539e225
--- /dev/null
+++ b/vendor/ezyang/htmlpurifier/library/HTMLPurifier.php
@@ -0,0 +1,292 @@
+<?php
+
+/*! @mainpage
+ *
+ * HTML Purifier is an HTML filter that will take an arbitrary snippet of
+ * HTML and rigorously test, validate and filter it into a version that
+ * is safe for output onto webpages. It achieves this by:
+ *
+ *  -# Lexing (parsing into tokens) the document,
+ *  -# Executing various strategies on the tokens:
+ *      -# Removing all elements not in the whitelist,
+ *      -# Making the tokens well-formed,
+ *      -# Fixing the nesting of the nodes, and
+ *      -# Validating attributes of the nodes; and
+ *  -# Generating HTML from the purified tokens.
+ *
+ * However, most users will only need to interface with the HTMLPurifier
+ * and HTMLPurifier_Config.
+ */
+
+/*
+    HTML Purifier 4.9.2 - Standards Compliant HTML Filtering
+    Copyright (C) 2006-2008 Edward Z. Yang
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+/**
+ * Facade that coordinates HTML Purifier's subsystems in order to purify HTML.
+ *
+ * @note There are several points in which configuration can be specified
+ *       for HTML Purifier.  The precedence of these (from lowest to
+ *       highest) is as follows:
+ *          -# Instance: new HTMLPurifier($config)
+ *          -# Invocation: purify($html, $config)
+ *       These configurations are entirely independent of each other and
+ *       are *not* merged (this behavior may change in the future).
+ *
+ * @todo We need an easier way to inject strategies using the configuration
+ *       object.
+ */
+class HTMLPurifier
+{
+
+    /**
+     * Version of HTML Purifier.
+     * @type string
+     */
+    public $version = '4.9.2';
+
+    /**
+     * Constant with version of HTML Purifier.
+     */
+    const VERSION = '4.9.2';
+
+    /**
+     * Global configuration object.
+     * @type HTMLPurifier_Config
+     */
+    public $config;
+
+    /**
+     * Array of extra filter objects to run on HTML,
+     * for backwards compatibility.
+     * @type HTMLPurifier_Filter[]
+     */
+    private $filters = array();
+
+    /**
+     * Single instance of HTML Purifier.
+     * @type HTMLPurifier
+     */
+    private static $instance;
+
+    /**
+     * @type HTMLPurifier_Strategy_Core
+     */
+    protected $strategy;
+
+    /**
+     * @type HTMLPurifier_Generator
+     */
+    protected $generator;
+
+    /**
+     * Resultant context of last run purification.
+     * Is an array of contexts if the last called method was purifyArray().
+     * @type HTMLPurifier_Context
+     */
+    public $context;
+
+    /**
+     * Initializes the purifier.
+     *
+     * @param HTMLPurifier_Config|mixed $config Optional HTMLPurifier_Config object
+     *                for all instances of the purifier, if omitted, a default
+     *                configuration is supplied (which can be overridden on a
+     *                per-use basis).
+     *                The parameter can also be any type that
+     *                HTMLPurifier_Config::create() supports.
+     */
+    public function __construct($config = null)
+    {
+        $this->config = HTMLPurifier_Config::create($config);
+        $this->strategy = new HTMLPurifier_Strategy_Core();
+    }
+
+    /**
+     * Adds a filter to process the output. First come first serve
+     *
+     * @param HTMLPurifier_Filter $filter HTMLPurifier_Filter object
+     */
+    public function addFilter($filter)
+    {
+        trigger_error(
+            'HTMLPurifier->addFilter() is deprecated, use configuration directives' .
+            ' in the Filter namespace or Filter.Custom',
+            E_USER_WARNING
+        );
+        $this->filters[] = $filter;
+    }
+
+    /**
+     * Filters an HTML snippet/document to be XSS-free and standards-compliant.
+     *
+     * @param string $html String of HTML to purify
+     * @param HTMLPurifier_Config $config Config object for this operation,
+     *                if omitted, defaults to the config object specified during this
+     *                object's construction. The parameter can also be any type
+     *                that HTMLPurifier_Config::create() supports.
+     *
+     * @return string Purified HTML
+     */
+    public function purify($html, $config = null)
+    {
+        // :TODO: make the config merge in, instead of replace
+        $config = $config ? HTMLPurifier_Config::create($config) : $this->config;
+
+        // implementation is partially environment dependant, partially
+        // configuration dependant
+        $lexer = HTMLPurifier_Lexer::create($config);
+
+        $context = new HTMLPurifier_Context();
+
+        // setup HTML generator
+        $this->generator = new HTMLPurifier_Generator($config, $context);
+        $context->register('Generator', $this->generator);
+
+        // set up global context variables
+        if ($config->get('Core.CollectErrors')) {
+            // may get moved out if other facilities use it
+            $language_factory = HTMLPurifier_LanguageFactory::instance();
+            $language = $language_factory->create($config, $context);
+            $context->register('Locale', $language);
+
+            $error_collector = new HTMLPurifier_ErrorCollector($context);
+            $context->register('ErrorCollector', $error_collector);
+        }
+
+        // setup id_accumulator context, necessary due to the fact that
+        // AttrValidator can be called from many places
+        $id_accumulator = HTMLPurifier_IDAccumulator::build($config, $context);
+        $context->register('IDAccumulator', $id_accumulator);
+
+        $html = HTMLPurifier_Encoder::convertToUTF8($html, $config, $context);
+
+        // setup filters
+        $filter_flags = $config->getBatch('Filter');
+        $custom_filters = $filter_flags['Custom'];
+        unset($filter_flags['Custom']);
+        $filters = array();
+        foreach ($filter_flags as $filter => $flag) {
+            if (!$flag) {
+                continue;
+            }
+            if (strpos($filter, '.') !== false) {
+                continue;
+            }
+            $class = "HTMLPurifier_Filter_$filter";
+            $filters[] = new $class;
+        }
+        foreach ($custom_filters as $filter) {
+            // maybe "HTMLPurifier_Filter_$filter", but be consistent with AutoFormat
+            $filters[] = $filter;
+        }
+        $filters = array_merge($filters, $this->filters);
+        // maybe prepare(), but later
+
+        for ($i = 0, $filter_size = count($filters); $i < $filter_size; $i++) {
+            $html = $filters[$i]->preFilter($html, $config, $context);
+        }
+
+        // purified HTML
+        $html =
+            $this->generator->generateFromTokens(
+                // list of tokens
+                $this->strategy->execute(
+                    // list of un-purified tokens
+                    $lexer->tokenizeHTML(
+                        // un-purified HTML
+                        $html,
+                        $config,
+                        $context
+                    ),
+                    $config,
+                    $context
+                )
+            );
+
+        for ($i = $filter_size - 1; $i >= 0; $i--) {
+            $html = $filters[$i]->postFilter($html, $config, $context);
+        }
+
+        $html = HTMLPurifier_Encoder::convertFromUTF8($html, $config, $context);
+        $this->context =& $context;
+        return $html;
+    }
+
+    /**
+     * Filters an array of HTML snippets
+     *
+     * @param string[] $array_of_html Array of html snippets
+     * @param HTMLPurifier_Config $config Optional config object for this operation.
+     *                See HTMLPurifier::purify() for more details.
+     *
+     * @return string[] Array of purified HTML
+     */
+    public function purifyArray($array_of_html, $config = null)
+    {
+        $context_array = array();
+        foreach ($array_of_html as $key => $html) {
+            $array_of_html[$key] = $this->purify($html, $config);
+            $context_array[$key] = $this->context;
+        }
+        $this->context = $context_array;
+        return $array_of_html;
+    }
+
+    /**
+     * Singleton for enforcing just one HTML Purifier in your system
+     *
+     * @param HTMLPurifier|HTMLPurifier_Config $prototype Optional prototype
+     *                   HTMLPurifier instance to overload singleton with,
+     *                   or HTMLPurifier_Config instance to configure the
+     *                   generated version with.
+     *
+     * @return HTMLPurifier
+     */
+    public static function instance($prototype = null)
+    {
+        if (!self::$instance || $prototype) {
+            if ($prototype instanceof HTMLPurifier) {
+                self::$instance = $prototype;
+            } elseif ($prototype) {
+                self::$instance = new HTMLPurifier($prototype);
+            } else {
+                self::$instance = new HTMLPurifier();
+            }
+        }
+        return self::$instance;
+    }
+
+    /**
+     * Singleton for enforcing just one HTML Purifier in your system
+     *
+     * @param HTMLPurifier|HTMLPurifier_Config $prototype Optional prototype
+     *                   HTMLPurifier instance to overload singleton with,
+     *                   or HTMLPurifier_Config instance to configure the
+     *                   generated version with.
+     *
+     * @return HTMLPurifier
+     * @note Backwards compatibility, see instance()
+     */
+    public static function getInstance($prototype = null)
+    {
+        return HTMLPurifier::instance($prototype);
+    }
+}
+
+// vim: et sw=4 sts=4