wp-includes/SimplePie/Locator.php

   1 <?php
   2 /**
   3  * SimplePie
   4  *
   5  * A PHP-Based RSS and Atom Feed Framework.
   6  * Takes the hard work out of managing a complete RSS/Atom solution.
   7  *
   8  * Copyright (c) 2004-2012, Ryan Parman, Geoffrey Sneddon, Ryan McCue, and contributors
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without modification, are
  12  * permitted provided that the following conditions are met:
  13  *
  14  *      * Redistributions of source code must retain the above copyright notice, this list of
  15  *        conditions and the following disclaimer.
  16  *
  17  *      * Redistributions in binary form must reproduce the above copyright notice, this list
  18  *        of conditions and the following disclaimer in the documentation and/or other materials
  19  *        provided with the distribution.
  20  *
  21  *      * Neither the name of the SimplePie Team nor the names of its contributors may be used
  22  *        to endorse or promote products derived from this software without specific prior
  23  *        written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
  26  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  27  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS
  28  * AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  30  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  31  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  32  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  33  * POSSIBILITY OF SUCH DAMAGE.
  34  *
  35  * @package SimplePie
  36  * @version 1.3.1
  37  * @copyright 2004-2012 Ryan Parman, Geoffrey Sneddon, Ryan McCue
  38  * @author Ryan Parman
  39  * @author Geoffrey Sneddon
  40  * @author Ryan McCue
  41  * @link http://simplepie.org/ SimplePie
  42  * @license http://www.opensource.org/licenses/bsd-license.php BSD License
  43  */
  44
  45 /**
  46  * Used for feed auto-discovery
  47  *
  48  *
  49  * This class can be overloaded with {@see SimplePie::set_locator_class()}
  50  *
  51  * @package SimplePie
  52  */
  53 class SimplePie_Locator
  54 {
  55         var $useragent;
  56         var $timeout;
  57         var $file;
  58         var $local = array();
  59         var $elsewhere = array();
  60         var $cached_entities = array();
  61         var $http_base;
  62         var $base;
  63         var $base_location = 0;
  64         var $checked_feeds = 0;
  65         var $max_checked_feeds = 10;
  66         protected $registry;
  67
  68         public function __construct(SimplePie_File $file, $timeout = 10, $useragent = null, $max_checked_feeds = 10)
  69         {
  70                 $this->file = $file;
  71                 $this->useragent = $useragent;
  72                 $this->timeout = $timeout;
  73                 $this->max_checked_feeds = $max_checked_feeds;
  74
  75                 if (class_exists('DOMDocument'))
  76                 {
  77                         $this->dom = new DOMDocument();
  78
  79                         set_error_handler(array('SimplePie_Misc', 'silence_errors'));
  80                         $this->dom->loadHTML($this->file->body);
  81                         restore_error_handler();
  82                 }
  83                 else
  84                 {
  85                         $this->dom = null;
  86                 }
  87         }
  88
  89         public function set_registry(SimplePie_Registry $registry)
  90         {
  91                 $this->registry = $registry;
  92         }
  93
  94         public function find($type = SIMPLEPIE_LOCATOR_ALL, &$working)
  95         {
  96                 if ($this->is_feed($this->file))
  97                 {
  98                         return $this->file;
  99                 }
 100
 101                 if ($this->file->method & SIMPLEPIE_FILE_SOURCE_REMOTE)
 102                 {
 103                         $sniffer = $this->registry->create('Content_Type_Sniffer', array($this->file));
 104                         if ($sniffer->get_type() !== 'text/html')
 105                         {
 106                                 return null;
 107                         }
 108                 }
 109
 110                 if ($type & ~SIMPLEPIE_LOCATOR_NONE)
 111                 {
 112                         $this->get_base();
 113                 }
 114
 115                 if ($type & SIMPLEPIE_LOCATOR_AUTODISCOVERY && $working = $this->autodiscovery())
 116                 {
 117                         return $working[0];
 118                 }
 119
 120                 if ($type & (SIMPLEPIE_LOCATOR_LOCAL_EXTENSION | SIMPLEPIE_LOCATOR_LOCAL_BODY | SIMPLEPIE_LOCATOR_REMOTE_EXTENSION | SIMPLEPIE_LOCATOR_REMOTE_BODY) && $this->get_links())
 121                 {
 122                         if ($type & SIMPLEPIE_LOCATOR_LOCAL_EXTENSION && $working = $this->extension($this->local))
 123                         {
 124                                 return $working;
 125                         }
 126
 127                         if ($type & SIMPLEPIE_LOCATOR_LOCAL_BODY && $working = $this->body($this->local))
 128                         {
 129                                 return $working;
 130                         }
 131
 132                         if ($type & SIMPLEPIE_LOCATOR_REMOTE_EXTENSION && $working = $this->extension($this->elsewhere))
 133                         {
 134                                 return $working;
 135                         }
 136
 137                         if ($type & SIMPLEPIE_LOCATOR_REMOTE_BODY && $working = $this->body($this->elsewhere))
 138                         {
 139                                 return $working;
 140                         }
 141                 }
 142                 return null;
 143         }
 144
 145         public function is_feed($file)
 146         {
 147                 if ($file->method & SIMPLEPIE_FILE_SOURCE_REMOTE)
 148                 {
 149                         $sniffer = $this->registry->create('Content_Type_Sniffer', array($file));
 150                         $sniffed = $sniffer->get_type();
 151                         if (in_array($sniffed, array('application/rss+xml', 'application/rdf+xml', 'text/rdf', 'application/atom+xml', 'text/xml', 'application/xml')))
 152                         {
 153                                 return true;
 154                         }
 155                         else
 156                         {
 157                                 return false;
 158                         }
 159                 }
 160                 elseif ($file->method & SIMPLEPIE_FILE_SOURCE_LOCAL)
 161                 {
 162                         return true;
 163                 }
 164                 else
 165                 {
 166                         return false;
 167                 }
 168         }
 169
 170         public function get_base()
 171         {
 172                 if ($this->dom === null)
 173                 {
 174                         throw new SimplePie_Exception('DOMDocument not found, unable to use locator');
 175                 }
 176                 $this->http_base = $this->file->url;
 177                 $this->base = $this->http_base;
 178                 $elements = $this->dom->getElementsByTagName('base');
 179                 foreach ($elements as $element)
 180                 {
 181                         if ($element->hasAttribute('href'))
 182                         {
 183                                 $base = $this->registry->call('Misc', 'absolutize_url', array(trim($element->getAttribute('href')), $this->http_base));
 184                                 if ($base === false)
 185                                 {
 186                                         continue;
 187                                 }
 188                                 $this->base = $base;
 189                                 $this->base_location = method_exists($element, 'getLineNo') ? $element->getLineNo() : 0;
 190                                 break;
 191                         }
 192                 }
 193         }
 194
 195         public function autodiscovery()
 196         {
 197                 $done = array();
 198                 $feeds = array();
 199                 $feeds = array_merge($feeds, $this->search_elements_by_tag('link', $done, $feeds));
 200                 $feeds = array_merge($feeds, $this->search_elements_by_tag('a', $done, $feeds));
 201                 $feeds = array_merge($feeds, $this->search_elements_by_tag('area', $done, $feeds));
 202
 203                 if (!empty($feeds))
 204                 {
 205                         return array_values($feeds);
 206                 }
 207                 else
 208                 {
 209                         return null;
 210                 }
 211         }
 212
 213         protected function search_elements_by_tag($name, &$done, $feeds)
 214         {
 215                 if ($this->dom === null)
 216                 {
 217                         throw new SimplePie_Exception('DOMDocument not found, unable to use locator');
 218                 }
 219
 220                 $links = $this->dom->getElementsByTagName($name);
 221                 foreach ($links as $link)
 222                 {
 223                         if ($this->checked_feeds === $this->max_checked_feeds)
 224                         {
 225                                 break;
 226                         }
 227                         if ($link->hasAttribute('href') && $link->hasAttribute('rel'))
 228                         {
 229                                 $rel = array_unique($this->registry->call('Misc', 'space_seperated_tokens', array(strtolower($link->getAttribute('rel')))));
 230                                 $line = method_exists($link, 'getLineNo') ? $link->getLineNo() : 1;
 231
 232                                 if ($this->base_location < $line)
 233                                 {
 234                                         $href = $this->registry->call('Misc', 'absolutize_url', array(trim($link->getAttribute('href')), $this->base));
 235                                 }
 236                                 else
 237                                 {
 238                                         $href = $this->registry->call('Misc', 'absolutize_url', array(trim($link->getAttribute('href')), $this->http_base));
 239                                 }
 240                                 if ($href === false)
 241                                 {
 242                                         continue;
 243                                 }
 244
 245                                 if (!in_array($href, $done) && in_array('feed', $rel) || (in_array('alternate', $rel) && !in_array('stylesheet', $rel) && $link->hasAttribute('type') && in_array(strtolower($this->registry->call('Misc', 'parse_mime', array($link->getAttribute('type')))), array('application/rss+xml', 'application/atom+xml'))) && !isset($feeds[$href]))
 246                                 {
 247                                         $this->checked_feeds++;
 248                                         $headers = array(
 249                                                 'Accept' => 'application/atom+xml, application/rss+xml, application/rdf+xml;q=0.9, application/xml;q=0.8, text/xml;q=0.8, text/html;q=0.7, unknown/unknown;q=0.1, application/unknown;q=0.1, */*;q=0.1',
 250                                         );
 251                                         $feed = $this->registry->create('File', array($href, $this->timeout, 5, $headers, $this->useragent));
 252                                         if ($feed->success && ($feed->method & SIMPLEPIE_FILE_SOURCE_REMOTE === 0 || ($feed->status_code === 200 || $feed->status_code > 206 && $feed->status_code < 300)) && $this->is_feed($feed))
 253                                         {
 254                                                 $feeds[$href] = $feed;
 255                                         }
 256                                 }
 257                                 $done[] = $href;
 258                         }
 259                 }
 260
 261                 return $feeds;
 262         }
 263
 264         public function get_links()
 265         {
 266                 if ($this->dom === null)
 267                 {
 268                         throw new SimplePie_Exception('DOMDocument not found, unable to use locator');
 269                 }
 270
 271                 $links = $this->dom->getElementsByTagName('a');
 272                 foreach ($links as $link)
 273                 {
 274                         if ($link->hasAttribute('href'))
 275                         {
 276                                 $href = trim($link->getAttribute('href'));
 277                                 $parsed = $this->registry->call('Misc', 'parse_url', array($href));
 278                                 if ($parsed['scheme'] === '' || preg_match('/^(http(s)|feed)?$/i', $parsed['scheme']))
 279                                 {
 280                                         if (method_exists($link, 'getLineNo') && $this->base_location < $link->getLineNo())
 281                                         {
 282                                                 $href = $this->registry->call('Misc', 'absolutize_url', array(trim($link->getAttribute('href')), $this->base));
 283                                         }
 284                                         else
 285                                         {
 286                                                 $href = $this->registry->call('Misc', 'absolutize_url', array(trim($link->getAttribute('href')), $this->http_base));
 287                                         }
 288                                         if ($href === false)
 289                                         {
 290                                                 continue;
 291                                         }
 292
 293                                         $current = $this->registry->call('Misc', 'parse_url', array($this->file->url));
 294
 295                                         if ($parsed['authority'] === '' || $parsed['authority'] === $current['authority'])
 296                                         {
 297                                                 $this->local[] = $href;
 298                                         }
 299                                         else
 300                                         {
 301                                                 $this->elsewhere[] = $href;
 302                                         }
 303                                 }
 304                         }
 305                 }
 306                 $this->local = array_unique($this->local);
 307                 $this->elsewhere = array_unique($this->elsewhere);
 308                 if (!empty($this->local) || !empty($this->elsewhere))
 309                 {
 310                         return true;
 311                 }
 312                 return null;
 313         }
 314
 315         public function extension(&$array)
 316         {
 317                 foreach ($array as $key => $value)
 318                 {
 319                         if ($this->checked_feeds === $this->max_checked_feeds)
 320                         {
 321                                 break;
 322                         }
 323                         if (in_array(strtolower(strrchr($value, '.')), array('.rss', '.rdf', '.atom', '.xml')))
 324                         {
 325                                 $this->checked_feeds++;
 326
 327                                 $headers = array(
 328                                         'Accept' => 'application/atom+xml, application/rss+xml, application/rdf+xml;q=0.9, application/xml;q=0.8, text/xml;q=0.8, text/html;q=0.7, unknown/unknown;q=0.1, application/unknown;q=0.1, */*;q=0.1',
 329                                 );
 330                                 $feed = $this->registry->create('File', array($value, $this->timeout, 5, $headers, $this->useragent));
 331                                 if ($feed->success && ($feed->method & SIMPLEPIE_FILE_SOURCE_REMOTE === 0 || ($feed->status_code === 200 || $feed->status_code > 206 && $feed->status_code < 300)) && $this->is_feed($feed))
 332                                 {
 333                                         return $feed;
 334                                 }
 335                                 else
 336                                 {
 337                                         unset($array[$key]);
 338                                 }
 339                         }
 340                 }
 341                 return null;
 342         }
 343
 344         public function body(&$array)
 345         {
 346                 foreach ($array as $key => $value)
 347                 {
 348                         if ($this->checked_feeds === $this->max_checked_feeds)
 349                         {
 350                                 break;
 351                         }
 352                         if (preg_match('/(rss|rdf|atom|xml)/i', $value))
 353                         {
 354                                 $this->checked_feeds++;
 355                                 $headers = array(
 356                                         'Accept' => 'application/atom+xml, application/rss+xml, application/rdf+xml;q=0.9, application/xml;q=0.8, text/xml;q=0.8, text/html;q=0.7, unknown/unknown;q=0.1, application/unknown;q=0.1, */*;q=0.1',
 357                                 );
 358                                 $feed = $this->registry->create('File', array($value, $this->timeout, 5, null, $this->useragent));
 359                                 if ($feed->success && ($feed->method & SIMPLEPIE_FILE_SOURCE_REMOTE === 0 || ($feed->status_code === 200 || $feed->status_code > 206 && $feed->status_code < 300)) && $this->is_feed($feed))
 360                                 {
 361                                         return $feed;
 362                                 }
 363                                 else
 364                                 {
 365                                         unset($array[$key]);
 366                                 }
 367                         }
 368                 }
 369                 return null;
 370         }
 371 }
 372