1 <?php
  2 
  3 /**
  4  * @package     Joomla.Platform
  5  * @subpackage  FileSystem
  6  *
  7  * @copyright   Copyright (C) 2005 - 2017 Open Source Matters, Inc. All rights reserved.
  8  * @license     GNU General Public License version 2 or later; see LICENSE
  9  */
 10 
 11 defined('JPATH_PLATFORM') or die;
 12 
 13 jimport('joomla.filesystem.file');
 14 
 15 /**
 16  * A Unified Diff Format Patcher class
 17  *
 18  * @link   http://sourceforge.net/projects/phppatcher/ This has been derived from the PhpPatcher version 0.1.1 written by Giuseppe Mazzotta
 19  * @since  12.1
 20  */
 21 class JFilesystemPatcher
 22 {
 23     /**
 24      * Regular expression for searching source files
 25      */
 26     const SRC_FILE = '/^---\\s+(\\S+)\s+\\d{1,4}-\\d{1,2}-\\d{1,2}\\s+\\d{1,2}:\\d{1,2}:\\d{1,2}(\\.\\d+)?\\s+(\+|-)\\d{4}/A';
 27 
 28     /**
 29      * Regular expression for searching destination files
 30      */
 31     const DST_FILE = '/^\\+\\+\\+\\s+(\\S+)\s+\\d{1,4}-\\d{1,2}-\\d{1,2}\\s+\\d{1,2}:\\d{1,2}:\\d{1,2}(\\.\\d+)?\\s+(\+|-)\\d{4}/A';
 32 
 33     /**
 34      * Regular expression for searching hunks of differences
 35      */
 36     const HUNK = '/@@ -(\\d+)(,(\\d+))?\\s+\\+(\\d+)(,(\\d+))?\\s+@@($)/A';
 37 
 38     /**
 39      * Regular expression for splitting lines
 40      */
 41     const SPLIT = '/(\r\n)|(\r)|(\n)/';
 42 
 43     /**
 44      * @var    array  sources files
 45      * @since  12.1
 46      */
 47     protected $sources = array();
 48 
 49     /**
 50      * @var    array  destination files
 51      * @since  12.1
 52      */
 53     protected $destinations = array();
 54 
 55     /**
 56      * @var    array  removal files
 57      * @since  12.1
 58      */
 59     protected $removals = array();
 60 
 61     /**
 62      * @var    array  patches
 63      * @since  12.1
 64      */
 65     protected $patches = array();
 66 
 67     /**
 68      * @var    array  instance of this class
 69      * @since  12.1
 70      */
 71     protected static $instance;
 72 
 73     /**
 74      * Constructor
 75      *
 76      * The constructor is protected to force the use of JFilesystemPatcher::getInstance()
 77      *
 78      * @since   12.1
 79      */
 80     protected function __construct()
 81     {
 82     }
 83 
 84     /**
 85      * Method to get a patcher
 86      *
 87      * @return  JFilesystemPatcher  an instance of the patcher
 88      *
 89      * @since   12.1
 90      */
 91     public static function getInstance()
 92     {
 93         if (!isset(static::$instance))
 94         {
 95             static::$instance = new static;
 96         }
 97 
 98         return static::$instance;
 99     }
100 
101     /**
102      * Reset the pacher
103      *
104      * @return  JFilesystemPatcher  This object for chaining
105      *
106      * @since   12.1
107      */
108     public function reset()
109     {
110         $this->sources = array();
111         $this->destinations = array();
112         $this->removals = array();
113         $this->patches = array();
114 
115         return $this;
116     }
117 
118     /**
119      * Apply the patches
120      *
121      * @return  integer  The number of files patched
122      *
123      * @since   12.1
124      * @throws  RuntimeException
125      */
126     public function apply()
127     {
128         foreach ($this->patches as $patch)
129         {
130             // Separate the input into lines
131             $lines = self::splitLines($patch['udiff']);
132 
133             // Loop for each header
134             while (self::findHeader($lines, $src, $dst))
135             {
136                 $done = false;
137 
138                 $regex = '#^([^/]*/)*#';
139                 if ($patch['strip'] !== null)
140                 {
141                     $regex = '#^([^/]*/){' . (int) $patch['strip'] . '}#';
142                 }
143 
144                 $src = $patch['root'] . preg_replace($regex, '', $src);
145                 $dst = $patch['root'] . preg_replace($regex, '', $dst);
146 
147                 // Loop for each hunk of differences
148                 while (self::findHunk($lines, $src_line, $src_size, $dst_line, $dst_size))
149                 {
150                     $done = true;
151 
152                     // Apply the hunk of differences
153                     $this->applyHunk($lines, $src, $dst, $src_line, $src_size, $dst_line, $dst_size);
154                 }
155 
156                 // If no modifications were found, throw an exception
157                 if (!$done)
158                 {
159                     throw new RuntimeException('Invalid Diff');
160                 }
161             }
162         }
163 
164         // Initialize the counter
165         $done = 0;
166 
167         // Patch each destination file
168         foreach ($this->destinations as $file => $content)
169         {
170             $buffer = implode("\n", $content);
171 
172             if (JFile::write($file, $buffer))
173             {
174                 if (isset($this->sources[$file]))
175                 {
176                     $this->sources[$file] = $content;
177                 }
178 
179                 $done++;
180             }
181         }
182 
183         // Remove each removed file
184         foreach ($this->removals as $file)
185         {
186             if (JFile::delete($file))
187             {
188                 if (isset($this->sources[$file]))
189                 {
190                     unset($this->sources[$file]);
191                 }
192 
193                 $done++;
194             }
195         }
196 
197         // Clear the destinations cache
198         $this->destinations = array();
199 
200         // Clear the removals
201         $this->removals = array();
202 
203         // Clear the patches
204         $this->patches = array();
205 
206         return $done;
207     }
208 
209     /**
210      * Add a unified diff file to the patcher
211      *
212      * @param   string  $filename  Path to the unified diff file
213      * @param   string  $root      The files root path
214      * @param   string  $strip     The number of '/' to strip
215      *
216      * @return  JFilesystemPatch $this for chaining
217      *
218      * @since   12.1
219      */
220     public function addFile($filename, $root = JPATH_BASE, $strip = 0)
221     {
222         return $this->add(file_get_contents($filename), $root, $strip);
223     }
224 
225     /**
226      * Add a unified diff string to the patcher
227      *
228      * @param   string  $udiff  Unified diff input string
229      * @param   string  $root   The files root path
230      * @param   string  $strip  The number of '/' to strip
231      *
232      * @return  JFilesystemPatch $this for chaining
233      *
234      * @since   12.1
235      */
236     public function add($udiff, $root = JPATH_BASE, $strip = 0)
237     {
238         $this->patches[] = array(
239             'udiff' => $udiff,
240             'root' => isset($root) ? rtrim($root, DIRECTORY_SEPARATOR) . DIRECTORY_SEPARATOR : '',
241             'strip' => $strip,
242         );
243 
244         return $this;
245     }
246 
247     /**
248      * Separate CR or CRLF lines
249      *
250      * @param   string  $data  Input string
251      *
252      * @return  array  The lines of the inputdestination file
253      *
254      * @since   12.1
255      */
256     protected static function splitLines($data)
257     {
258         return preg_split(self::SPLIT, $data);
259     }
260 
261     /**
262      * Find the diff header
263      *
264      * The internal array pointer of $lines is on the next line after the finding
265      *
266      * @param   array   &$lines  The udiff array of lines
267      * @param   string  &$src    The source file
268      * @param   string  &$dst    The destination file
269      *
270      * @return  boolean  TRUE in case of success, FALSE in case of failure
271      *
272      * @since   12.1
273      * @throws  RuntimeException
274      */
275     protected static function findHeader(&$lines, &$src, &$dst)
276     {
277         // Get the current line
278         $line = current($lines);
279 
280         // Search for the header
281         while ($line !== false && !preg_match(self::SRC_FILE, $line, $m))
282         {
283             $line = next($lines);
284         }
285 
286         if ($line === false)
287         {
288             // No header found, return false
289             return false;
290         }
291 
292         // Set the source file
293         $src = $m[1];
294 
295         // Advance to the next line
296         $line = next($lines);
297 
298         if ($line === false)
299         {
300             throw new RuntimeException('Unexpected EOF');
301         }
302 
303         // Search the destination file
304         if (!preg_match(self::DST_FILE, $line, $m))
305         {
306             throw new RuntimeException('Invalid Diff file');
307         }
308 
309         // Set the destination file
310         $dst = $m[1];
311 
312         // Advance to the next line
313         if (next($lines) === false)
314         {
315             throw new RuntimeException('Unexpected EOF');
316         }
317 
318         return true;
319     }
320 
321     /**
322      * Find the next hunk of difference
323      *
324      * The internal array pointer of $lines is on the next line after the finding
325      *
326      * @param   array   &$lines     The udiff array of lines
327      * @param   string  &$src_line  The beginning of the patch for the source file
328      * @param   string  &$src_size  The size of the patch for the source file
329      * @param   string  &$dst_line  The beginning of the patch for the destination file
330      * @param   string  &$dst_size  The size of the patch for the destination file
331      *
332      * @return  boolean  TRUE in case of success, false in case of failure
333      *
334      * @since   12.1
335      * @throws  RuntimeException
336      */
337     protected static function findHunk(&$lines, &$src_line, &$src_size, &$dst_line, &$dst_size)
338     {
339         $line = current($lines);
340 
341         if (preg_match(self::HUNK, $line, $m))
342         {
343             $src_line = (int) $m[1];
344 
345             $src_size = 1;
346             if ($m[3] !== '')
347             {
348                 $src_size = (int) $m[3];
349             }
350 
351             $dst_line = (int) $m[4];
352 
353             $dst_size = 1;
354             if ($m[6] !== '')
355             {
356                 $dst_size = (int) $m[6];
357             }
358 
359             if (next($lines) === false)
360             {
361                 throw new RuntimeException('Unexpected EOF');
362             }
363 
364             return true;
365         }
366 
367         return false;
368     }
369 
370     /**
371      * Apply the patch
372      *
373      * @param   array   &$lines    The udiff array of lines
374      * @param   string  $src       The source file
375      * @param   string  $dst       The destination file
376      * @param   string  $src_line  The beginning of the patch for the source file
377      * @param   string  $src_size  The size of the patch for the source file
378      * @param   string  $dst_line  The beginning of the patch for the destination file
379      * @param   string  $dst_size  The size of the patch for the destination file
380      *
381      * @return  void
382      *
383      * @since   12.1
384      * @throws  RuntimeException
385      */
386     protected function applyHunk(&$lines, $src, $dst, $src_line, $src_size, $dst_line, $dst_size)
387     {
388         $src_line--;
389         $dst_line--;
390         $line = current($lines);
391 
392         // Source lines (old file)
393         $source = array();
394 
395         // New lines (new file)
396         $destin = array();
397         $src_left = $src_size;
398         $dst_left = $dst_size;
399 
400         do
401         {
402             if (!isset($line[0]))
403             {
404                 $source[] = '';
405                 $destin[] = '';
406                 $src_left--;
407                 $dst_left--;
408             }
409             elseif ($line[0] == '-')
410             {
411                 if ($src_left == 0)
412                 {
413                     throw new RuntimeException(JText::sprintf('JLIB_FILESYSTEM_PATCHER_UNEXPECTED_REMOVE_LINE', key($lines)));
414                 }
415 
416                 $source[] = substr($line, 1);
417                 $src_left--;
418             }
419             elseif ($line[0] == '+')
420             {
421                 if ($dst_left == 0)
422                 {
423                     throw new RuntimeException(JText::sprintf('JLIB_FILESYSTEM_PATCHER_UNEXPECTED_ADD_LINE', key($lines)));
424                 }
425 
426                 $destin[] = substr($line, 1);
427                 $dst_left--;
428             }
429             elseif ($line != '\\ No newline at end of file')
430             {
431                 $line = substr($line, 1);
432                 $source[] = $line;
433                 $destin[] = $line;
434                 $src_left--;
435                 $dst_left--;
436             }
437 
438             if ($src_left == 0 && $dst_left == 0)
439             {
440                 // Now apply the patch, finally!
441                 if ($src_size > 0)
442                 {
443                     $src_lines = & $this->getSource($src);
444 
445                     if (!isset($src_lines))
446                     {
447                         throw new RuntimeException(JText::sprintf('JLIB_FILESYSTEM_PATCHER_UNEXISING_SOURCE', $src));
448                     }
449                 }
450 
451                 if ($dst_size > 0)
452                 {
453                     if ($src_size > 0)
454                     {
455                         $dst_lines = & $this->getDestination($dst, $src);
456                         $src_bottom = $src_line + count($source);
457 
458                         for ($l = $src_line;$l < $src_bottom;$l++)
459                         {
460                             if ($src_lines[$l] != $source[$l - $src_line])
461                             {
462                                 throw new RuntimeException(JText::sprintf('JLIB_FILESYSTEM_PATCHER_FAILED_VERIFY', $src, $l));
463                             }
464                         }
465 
466                         array_splice($dst_lines, $dst_line, count($source), $destin);
467                     }
468                     else
469                     {
470                         $this->destinations[$dst] = $destin;
471                     }
472                 }
473                 else
474                 {
475                     $this->removals[] = $src;
476                 }
477 
478                 next($lines);
479 
480                 return;
481             }
482 
483             $line = next($lines);
484         }
485 
486         while ($line !== false);
487         throw new RuntimeException('Unexpected EOF');
488     }
489 
490     /**
491      * Get the lines of a source file
492      *
493      * @param   string  $src  The path of a file
494      *
495      * @return  array  The lines of the source file
496      *
497      * @since   12.1
498      */
499     protected function &getSource($src)
500     {
501         if (!isset($this->sources[$src]))
502         {
503             $this->sources[$src] = null;
504             if (is_readable($src))
505             {
506                 $this->sources[$src] = self::splitLines(file_get_contents($src));
507             }
508         }
509 
510         return $this->sources[$src];
511     }
512 
513     /**
514      * Get the lines of a destination file
515      *
516      * @param   string  $dst  The path of a destination file
517      * @param   string  $src  The path of a source file
518      *
519      * @return  array  The lines of the destination file
520      *
521      * @since   12.1
522      */
523     protected function &getDestination($dst, $src)
524     {
525         if (!isset($this->destinations[$dst]))
526         {
527             $this->destinations[$dst] = $this->getSource($src);
528         }
529 
530         return $this->destinations[$dst];
531     }
532 }
533