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Diffstat (limited to 'platform/www/inc/DifferenceEngine.php')
| -rw-r--r-- | platform/www/inc/DifferenceEngine.php | 1544 |
1 files changed, 1544 insertions, 0 deletions
diff --git a/platform/www/inc/DifferenceEngine.php b/platform/www/inc/DifferenceEngine.php new file mode 100644 index 0000000..70877a4 --- /dev/null +++ b/platform/www/inc/DifferenceEngine.php @@ -0,0 +1,1544 @@ +<?php +/** + * A PHP diff engine for phpwiki. (Taken from phpwiki-1.3.3) + * + * Additions by Axel Boldt for MediaWiki + * + * @copyright (C) 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org> + * @license You may copy this code freely under the conditions of the GPL. + */ +define('USE_ASSERTS', function_exists('assert')); + +class _DiffOp { + var $type; + var $orig; + var $closing; + + /** + * @return _DiffOp + */ + function reverse() { + trigger_error("pure virtual", E_USER_ERROR); + } + + function norig() { + return $this->orig ? count($this->orig) : 0; + } + + function nclosing() { + return $this->closing ? count($this->closing) : 0; + } +} + +class _DiffOp_Copy extends _DiffOp { + var $type = 'copy'; + + function __construct($orig, $closing = false) { + if (!is_array($closing)) + $closing = $orig; + $this->orig = $orig; + $this->closing = $closing; + } + + function reverse() { + return new _DiffOp_Copy($this->closing, $this->orig); + } +} + +class _DiffOp_Delete extends _DiffOp { + var $type = 'delete'; + + function __construct($lines) { + $this->orig = $lines; + $this->closing = false; + } + + function reverse() { + return new _DiffOp_Add($this->orig); + } +} + +class _DiffOp_Add extends _DiffOp { + var $type = 'add'; + + function __construct($lines) { + $this->closing = $lines; + $this->orig = false; + } + + function reverse() { + return new _DiffOp_Delete($this->closing); + } +} + +class _DiffOp_Change extends _DiffOp { + var $type = 'change'; + + function __construct($orig, $closing) { + $this->orig = $orig; + $this->closing = $closing; + } + + function reverse() { + return new _DiffOp_Change($this->closing, $this->orig); + } +} + + +/** + * Class used internally by Diff to actually compute the diffs. + * + * The algorithm used here is mostly lifted from the perl module + * Algorithm::Diff (version 1.06) by Ned Konz, which is available at: + * http://www.perl.com/CPAN/authors/id/N/NE/NEDKONZ/Algorithm-Diff-1.06.zip + * + * More ideas are taken from: + * http://www.ics.uci.edu/~eppstein/161/960229.html + * + * Some ideas are (and a bit of code) are from from analyze.c, from GNU + * diffutils-2.7, which can be found at: + * ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz + * + * closingly, some ideas (subdivision by NCHUNKS > 2, and some optimizations) + * are my own. + * + * @author Geoffrey T. Dairiki + * @access private + */ +class _DiffEngine { + + var $xchanged = array(); + var $ychanged = array(); + var $xv = array(); + var $yv = array(); + var $xind = array(); + var $yind = array(); + var $seq; + var $in_seq; + var $lcs; + + /** + * @param array $from_lines + * @param array $to_lines + * @return _DiffOp[] + */ + function diff($from_lines, $to_lines) { + $n_from = count($from_lines); + $n_to = count($to_lines); + + $this->xchanged = $this->ychanged = array(); + $this->xv = $this->yv = array(); + $this->xind = $this->yind = array(); + unset($this->seq); + unset($this->in_seq); + unset($this->lcs); + + // Skip leading common lines. + for ($skip = 0; $skip < $n_from && $skip < $n_to; $skip++) { + if ($from_lines[$skip] != $to_lines[$skip]) + break; + $this->xchanged[$skip] = $this->ychanged[$skip] = false; + } + // Skip trailing common lines. + $xi = $n_from; + $yi = $n_to; + for ($endskip = 0; --$xi > $skip && --$yi > $skip; $endskip++) { + if ($from_lines[$xi] != $to_lines[$yi]) + break; + $this->xchanged[$xi] = $this->ychanged[$yi] = false; + } + + // Ignore lines which do not exist in both files. + for ($xi = $skip; $xi < $n_from - $endskip; $xi++) + $xhash[$from_lines[$xi]] = 1; + for ($yi = $skip; $yi < $n_to - $endskip; $yi++) { + $line = $to_lines[$yi]; + if (($this->ychanged[$yi] = empty($xhash[$line]))) + continue; + $yhash[$line] = 1; + $this->yv[] = $line; + $this->yind[] = $yi; + } + for ($xi = $skip; $xi < $n_from - $endskip; $xi++) { + $line = $from_lines[$xi]; + if (($this->xchanged[$xi] = empty($yhash[$line]))) + continue; + $this->xv[] = $line; + $this->xind[] = $xi; + } + + // Find the LCS. + $this->_compareseq(0, count($this->xv), 0, count($this->yv)); + + // Merge edits when possible + $this->_shift_boundaries($from_lines, $this->xchanged, $this->ychanged); + $this->_shift_boundaries($to_lines, $this->ychanged, $this->xchanged); + + // Compute the edit operations. + $edits = array(); + $xi = $yi = 0; + while ($xi < $n_from || $yi < $n_to) { + USE_ASSERTS && assert($yi < $n_to || $this->xchanged[$xi]); + USE_ASSERTS && assert($xi < $n_from || $this->ychanged[$yi]); + + // Skip matching "snake". + $copy = array(); + while ($xi < $n_from && $yi < $n_to && !$this->xchanged[$xi] && !$this->ychanged[$yi]) { + $copy[] = $from_lines[$xi++]; + ++$yi; + } + if ($copy) + $edits[] = new _DiffOp_Copy($copy); + + // Find deletes & adds. + $delete = array(); + while ($xi < $n_from && $this->xchanged[$xi]) + $delete[] = $from_lines[$xi++]; + + $add = array(); + while ($yi < $n_to && $this->ychanged[$yi]) + $add[] = $to_lines[$yi++]; + + if ($delete && $add) + $edits[] = new _DiffOp_Change($delete, $add); + elseif ($delete) + $edits[] = new _DiffOp_Delete($delete); + elseif ($add) + $edits[] = new _DiffOp_Add($add); + } + return $edits; + } + + + /** + * Divide the Largest Common Subsequence (LCS) of the sequences + * [XOFF, XLIM) and [YOFF, YLIM) into NCHUNKS approximately equally + * sized segments. + * + * Returns (LCS, PTS). LCS is the length of the LCS. PTS is an + * array of NCHUNKS+1 (X, Y) indexes giving the diving points between + * sub sequences. The first sub-sequence is contained in [X0, X1), + * [Y0, Y1), the second in [X1, X2), [Y1, Y2) and so on. Note + * that (X0, Y0) == (XOFF, YOFF) and + * (X[NCHUNKS], Y[NCHUNKS]) == (XLIM, YLIM). + * + * This function assumes that the first lines of the specified portions + * of the two files do not match, and likewise that the last lines do not + * match. The caller must trim matching lines from the beginning and end + * of the portions it is going to specify. + * + * @param integer $xoff + * @param integer $xlim + * @param integer $yoff + * @param integer $ylim + * @param integer $nchunks + * + * @return array + */ + function _diag($xoff, $xlim, $yoff, $ylim, $nchunks) { + $flip = false; + + if ($xlim - $xoff > $ylim - $yoff) { + // Things seems faster (I'm not sure I understand why) + // when the shortest sequence in X. + $flip = true; + list ($xoff, $xlim, $yoff, $ylim) = array($yoff, $ylim, $xoff, $xlim); + } + + if ($flip) + for ($i = $ylim - 1; $i >= $yoff; $i--) + $ymatches[$this->xv[$i]][] = $i; + else + for ($i = $ylim - 1; $i >= $yoff; $i--) + $ymatches[$this->yv[$i]][] = $i; + + $this->lcs = 0; + $this->seq[0]= $yoff - 1; + $this->in_seq = array(); + $ymids[0] = array(); + + $numer = $xlim - $xoff + $nchunks - 1; + $x = $xoff; + for ($chunk = 0; $chunk < $nchunks; $chunk++) { + if ($chunk > 0) + for ($i = 0; $i <= $this->lcs; $i++) + $ymids[$i][$chunk-1] = $this->seq[$i]; + + $x1 = $xoff + (int)(($numer + ($xlim-$xoff)*$chunk) / $nchunks); + for ( ; $x < $x1; $x++) { + $line = $flip ? $this->yv[$x] : $this->xv[$x]; + if (empty($ymatches[$line])) + continue; + $matches = $ymatches[$line]; + $switch = false; + foreach ($matches as $y) { + if ($switch && $y > $this->seq[$k-1]) { + USE_ASSERTS && assert($y < $this->seq[$k]); + // Optimization: this is a common case: + // next match is just replacing previous match. + $this->in_seq[$this->seq[$k]] = false; + $this->seq[$k] = $y; + $this->in_seq[$y] = 1; + } + else if (empty($this->in_seq[$y])) { + $k = $this->_lcs_pos($y); + USE_ASSERTS && assert($k > 0); + $ymids[$k] = $ymids[$k-1]; + $switch = true; + } + } + } + } + + $seps[] = $flip ? array($yoff, $xoff) : array($xoff, $yoff); + $ymid = $ymids[$this->lcs]; + for ($n = 0; $n < $nchunks - 1; $n++) { + $x1 = $xoff + (int)(($numer + ($xlim - $xoff) * $n) / $nchunks); + $y1 = $ymid[$n] + 1; + $seps[] = $flip ? array($y1, $x1) : array($x1, $y1); + } + $seps[] = $flip ? array($ylim, $xlim) : array($xlim, $ylim); + + return array($this->lcs, $seps); + } + + function _lcs_pos($ypos) { + $end = $this->lcs; + if ($end == 0 || $ypos > $this->seq[$end]) { + $this->seq[++$this->lcs] = $ypos; + $this->in_seq[$ypos] = 1; + return $this->lcs; + } + + $beg = 1; + while ($beg < $end) { + $mid = (int)(($beg + $end) / 2); + if ($ypos > $this->seq[$mid]) + $beg = $mid + 1; + else + $end = $mid; + } + + USE_ASSERTS && assert($ypos != $this->seq[$end]); + + $this->in_seq[$this->seq[$end]] = false; + $this->seq[$end] = $ypos; + $this->in_seq[$ypos] = 1; + return $end; + } + + /** + * Find LCS of two sequences. + * + * The results are recorded in the vectors $this->{x,y}changed[], by + * storing a 1 in the element for each line that is an insertion + * or deletion (ie. is not in the LCS). + * + * The subsequence of file 0 is [XOFF, XLIM) and likewise for file 1. + * + * Note that XLIM, YLIM are exclusive bounds. + * All line numbers are origin-0 and discarded lines are not counted. + * + * @param integer $xoff + * @param integer $xlim + * @param integer $yoff + * @param integer $ylim + */ + function _compareseq($xoff, $xlim, $yoff, $ylim) { + // Slide down the bottom initial diagonal. + while ($xoff < $xlim && $yoff < $ylim && $this->xv[$xoff] == $this->yv[$yoff]) { + ++$xoff; + ++$yoff; + } + + // Slide up the top initial diagonal. + while ($xlim > $xoff && $ylim > $yoff && $this->xv[$xlim - 1] == $this->yv[$ylim - 1]) { + --$xlim; + --$ylim; + } + + if ($xoff == $xlim || $yoff == $ylim) + $lcs = 0; + else { + // This is ad hoc but seems to work well. + //$nchunks = sqrt(min($xlim - $xoff, $ylim - $yoff) / 2.5); + //$nchunks = max(2,min(8,(int)$nchunks)); + $nchunks = min(7, $xlim - $xoff, $ylim - $yoff) + 1; + list ($lcs, $seps) + = $this->_diag($xoff,$xlim,$yoff, $ylim,$nchunks); + } + + if ($lcs == 0) { + // X and Y sequences have no common subsequence: + // mark all changed. + while ($yoff < $ylim) + $this->ychanged[$this->yind[$yoff++]] = 1; + while ($xoff < $xlim) + $this->xchanged[$this->xind[$xoff++]] = 1; + } + else { + // Use the partitions to split this problem into subproblems. + reset($seps); + $pt1 = $seps[0]; + while ($pt2 = next($seps)) { + $this->_compareseq ($pt1[0], $pt2[0], $pt1[1], $pt2[1]); + $pt1 = $pt2; + } + } + } + + /** + * Adjust inserts/deletes of identical lines to join changes + * as much as possible. + * + * We do something when a run of changed lines include a + * line at one end and has an excluded, identical line at the other. + * We are free to choose which identical line is included. + * `compareseq' usually chooses the one at the beginning, + * but usually it is cleaner to consider the following identical line + * to be the "change". + * + * This is extracted verbatim from analyze.c (GNU diffutils-2.7). + * + * @param array $lines + * @param array $changed + * @param array $other_changed + */ + function _shift_boundaries($lines, &$changed, $other_changed) { + $i = 0; + $j = 0; + + USE_ASSERTS && assert(count($lines) == count($changed)); + $len = count($lines); + $other_len = count($other_changed); + + while (1) { + /* + * Scan forwards to find beginning of another run of changes. + * Also keep track of the corresponding point in the other file. + * + * Throughout this code, $i and $j are adjusted together so that + * the first $i elements of $changed and the first $j elements + * of $other_changed both contain the same number of zeros + * (unchanged lines). + * Furthermore, $j is always kept so that $j == $other_len or + * $other_changed[$j] == false. + */ + while ($j < $other_len && $other_changed[$j]) + $j++; + + while ($i < $len && ! $changed[$i]) { + USE_ASSERTS && assert($j < $other_len && ! $other_changed[$j]); + $i++; + $j++; + while ($j < $other_len && $other_changed[$j]) + $j++; + } + + if ($i == $len) + break; + + $start = $i; + + // Find the end of this run of changes. + while (++$i < $len && $changed[$i]) + continue; + + do { + /* + * Record the length of this run of changes, so that + * we can later determine whether the run has grown. + */ + $runlength = $i - $start; + + /* + * Move the changed region back, so long as the + * previous unchanged line matches the last changed one. + * This merges with previous changed regions. + */ + while ($start > 0 && $lines[$start - 1] == $lines[$i - 1]) { + $changed[--$start] = 1; + $changed[--$i] = false; + while ($start > 0 && $changed[$start - 1]) + $start--; + USE_ASSERTS && assert($j > 0); + while ($other_changed[--$j]) + continue; + USE_ASSERTS && assert($j >= 0 && !$other_changed[$j]); + } + + /* + * Set CORRESPONDING to the end of the changed run, at the last + * point where it corresponds to a changed run in the other file. + * CORRESPONDING == LEN means no such point has been found. + */ + $corresponding = $j < $other_len ? $i : $len; + + /* + * Move the changed region forward, so long as the + * first changed line matches the following unchanged one. + * This merges with following changed regions. + * Do this second, so that if there are no merges, + * the changed region is moved forward as far as possible. + */ + while ($i < $len && $lines[$start] == $lines[$i]) { + $changed[$start++] = false; + $changed[$i++] = 1; + while ($i < $len && $changed[$i]) + $i++; + + USE_ASSERTS && assert($j < $other_len && ! $other_changed[$j]); + $j++; + if ($j < $other_len && $other_changed[$j]) { + $corresponding = $i; + while ($j < $other_len && $other_changed[$j]) + $j++; + } + } + } while ($runlength != $i - $start); + + /* + * If possible, move the fully-merged run of changes + * back to a corresponding run in the other file. + */ + while ($corresponding < $i) { + $changed[--$start] = 1; + $changed[--$i] = 0; + USE_ASSERTS && assert($j > 0); + while ($other_changed[--$j]) + continue; + USE_ASSERTS && assert($j >= 0 && !$other_changed[$j]); + } + } + } +} + +/** + * Class representing a 'diff' between two sequences of strings. + */ +class Diff { + + var $edits; + + /** + * Constructor. + * Computes diff between sequences of strings. + * + * @param array $from_lines An array of strings. + * (Typically these are lines from a file.) + * @param array $to_lines An array of strings. + */ + function __construct($from_lines, $to_lines) { + $eng = new _DiffEngine; + $this->edits = $eng->diff($from_lines, $to_lines); + //$this->_check($from_lines, $to_lines); + } + + /** + * Compute reversed Diff. + * + * SYNOPSIS: + * + * $diff = new Diff($lines1, $lines2); + * $rev = $diff->reverse(); + * + * @return Diff A Diff object representing the inverse of the + * original diff. + */ + function reverse() { + $rev = $this; + $rev->edits = array(); + foreach ($this->edits as $edit) { + $rev->edits[] = $edit->reverse(); + } + return $rev; + } + + /** + * Check for empty diff. + * + * @return bool True iff two sequences were identical. + */ + function isEmpty() { + foreach ($this->edits as $edit) { + if ($edit->type != 'copy') + return false; + } + return true; + } + + /** + * Compute the length of the Longest Common Subsequence (LCS). + * + * This is mostly for diagnostic purposed. + * + * @return int The length of the LCS. + */ + function lcs() { + $lcs = 0; + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $lcs += count($edit->orig); + } + return $lcs; + } + + /** + * Get the original set of lines. + * + * This reconstructs the $from_lines parameter passed to the + * constructor. + * + * @return array The original sequence of strings. + */ + function orig() { + $lines = array(); + + foreach ($this->edits as $edit) { + if ($edit->orig) + array_splice($lines, count($lines), 0, $edit->orig); + } + return $lines; + } + + /** + * Get the closing set of lines. + * + * This reconstructs the $to_lines parameter passed to the + * constructor. + * + * @return array The sequence of strings. + */ + function closing() { + $lines = array(); + + foreach ($this->edits as $edit) { + if ($edit->closing) + array_splice($lines, count($lines), 0, $edit->closing); + } + return $lines; + } + + /** + * Check a Diff for validity. + * + * This is here only for debugging purposes. + * + * @param mixed $from_lines + * @param mixed $to_lines + */ + function _check($from_lines, $to_lines) { + if (serialize($from_lines) != serialize($this->orig())) + trigger_error("Reconstructed original doesn't match", E_USER_ERROR); + if (serialize($to_lines) != serialize($this->closing())) + trigger_error("Reconstructed closing doesn't match", E_USER_ERROR); + + $rev = $this->reverse(); + if (serialize($to_lines) != serialize($rev->orig())) + trigger_error("Reversed original doesn't match", E_USER_ERROR); + if (serialize($from_lines) != serialize($rev->closing())) + trigger_error("Reversed closing doesn't match", E_USER_ERROR); + + $prevtype = 'none'; + foreach ($this->edits as $edit) { + if ($prevtype == $edit->type) + trigger_error("Edit sequence is non-optimal", E_USER_ERROR); + $prevtype = $edit->type; + } + + $lcs = $this->lcs(); + trigger_error("Diff okay: LCS = $lcs", E_USER_NOTICE); + } +} + +/** + * FIXME: bad name. + */ +class MappedDiff extends Diff { + /** + * Constructor. + * + * Computes diff between sequences of strings. + * + * This can be used to compute things like + * case-insensitve diffs, or diffs which ignore + * changes in white-space. + * + * @param string[] $from_lines An array of strings. + * (Typically these are lines from a file.) + * + * @param string[] $to_lines An array of strings. + * + * @param string[] $mapped_from_lines This array should + * have the same size number of elements as $from_lines. + * The elements in $mapped_from_lines and + * $mapped_to_lines are what is actually compared + * when computing the diff. + * + * @param string[] $mapped_to_lines This array should + * have the same number of elements as $to_lines. + */ + function __construct($from_lines, $to_lines, $mapped_from_lines, $mapped_to_lines) { + + assert(count($from_lines) == count($mapped_from_lines)); + assert(count($to_lines) == count($mapped_to_lines)); + + parent::__construct($mapped_from_lines, $mapped_to_lines); + + $xi = $yi = 0; + $ecnt = count($this->edits); + for ($i = 0; $i < $ecnt; $i++) { + $orig = &$this->edits[$i]->orig; + if (is_array($orig)) { + $orig = array_slice($from_lines, $xi, count($orig)); + $xi += count($orig); + } + + $closing = &$this->edits[$i]->closing; + if (is_array($closing)) { + $closing = array_slice($to_lines, $yi, count($closing)); + $yi += count($closing); + } + } + } +} + +/** + * A class to format Diffs + * + * This class formats the diff in classic diff format. + * It is intended that this class be customized via inheritance, + * to obtain fancier outputs. + */ +class DiffFormatter { + /** + * Number of leading context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + var $leading_context_lines = 0; + + /** + * Number of trailing context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + var $trailing_context_lines = 0; + + /** + * Format a diff. + * + * @param Diff $diff A Diff object. + * @return string The formatted output. + */ + function format($diff) { + + $xi = $yi = 1; + $x0 = $y0 = 0; + $block = false; + $context = array(); + + $nlead = $this->leading_context_lines; + $ntrail = $this->trailing_context_lines; + + $this->_start_diff(); + + foreach ($diff->edits as $edit) { + if ($edit->type == 'copy') { + if (is_array($block)) { + if (count($edit->orig) <= $nlead + $ntrail) { + $block[] = $edit; + } + else{ + if ($ntrail) { + $context = array_slice($edit->orig, 0, $ntrail); + $block[] = new _DiffOp_Copy($context); + } + $this->_block($x0, $ntrail + $xi - $x0, $y0, $ntrail + $yi - $y0, $block); + $block = false; + } + } + $context = $edit->orig; + } + else { + if (! is_array($block)) { + $context = array_slice($context, count($context) - $nlead); + $x0 = $xi - count($context); + $y0 = $yi - count($context); + $block = array(); + if ($context) + $block[] = new _DiffOp_Copy($context); + } + $block[] = $edit; + } + + if ($edit->orig) + $xi += count($edit->orig); + if ($edit->closing) + $yi += count($edit->closing); + } + + if (is_array($block)) + $this->_block($x0, $xi - $x0, $y0, $yi - $y0, $block); + + return $this->_end_diff(); + } + + /** + * @param int $xbeg + * @param int $xlen + * @param int $ybeg + * @param int $ylen + * @param array $edits + */ + function _block($xbeg, $xlen, $ybeg, $ylen, &$edits) { + $this->_start_block($this->_block_header($xbeg, $xlen, $ybeg, $ylen)); + foreach ($edits as $edit) { + if ($edit->type == 'copy') + $this->_context($edit->orig); + elseif ($edit->type == 'add') + $this->_added($edit->closing); + elseif ($edit->type == 'delete') + $this->_deleted($edit->orig); + elseif ($edit->type == 'change') + $this->_changed($edit->orig, $edit->closing); + else + trigger_error("Unknown edit type", E_USER_ERROR); + } + $this->_end_block(); + } + + function _start_diff() { + ob_start(); + } + + function _end_diff() { + $val = ob_get_contents(); + ob_end_clean(); + return $val; + } + + /** + * @param int $xbeg + * @param int $xlen + * @param int $ybeg + * @param int $ylen + * @return string + */ + function _block_header($xbeg, $xlen, $ybeg, $ylen) { + if ($xlen > 1) + $xbeg .= "," . ($xbeg + $xlen - 1); + if ($ylen > 1) + $ybeg .= "," . ($ybeg + $ylen - 1); + + return $xbeg . ($xlen ? ($ylen ? 'c' : 'd') : 'a') . $ybeg; + } + + /** + * @param string $header + */ + function _start_block($header) { + echo $header; + } + + function _end_block() { + } + + function _lines($lines, $prefix = ' ') { + foreach ($lines as $line) + echo "$prefix ".$this->_escape($line)."\n"; + } + + function _context($lines) { + $this->_lines($lines); + } + + function _added($lines) { + $this->_lines($lines, ">"); + } + function _deleted($lines) { + $this->_lines($lines, "<"); + } + + function _changed($orig, $closing) { + $this->_deleted($orig); + echo "---\n"; + $this->_added($closing); + } + + /** + * Escape string + * + * Override this method within other formatters if escaping required. + * Base class requires $str to be returned WITHOUT escaping. + * + * @param $str string Text string to escape + * @return string The escaped string. + */ + function _escape($str){ + return $str; + } +} + +/** + * Utilityclass for styling HTML formatted diffs + * + * Depends on global var $DIFF_INLINESTYLES, if true some minimal predefined + * inline styles are used. Useful for HTML mails and RSS feeds + * + * @author Andreas Gohr <andi@splitbrain.org> + */ +class HTMLDiff { + /** + * Holds the style names and basic CSS + */ + static public $styles = array( + 'diff-addedline' => 'background-color: #ddffdd;', + 'diff-deletedline' => 'background-color: #ffdddd;', + 'diff-context' => 'background-color: #f5f5f5;', + 'diff-mark' => 'color: #ff0000;', + ); + + /** + * Return a class or style parameter + * + * @param string $classname + * + * @return string + */ + static function css($classname){ + global $DIFF_INLINESTYLES; + + if($DIFF_INLINESTYLES){ + if(!isset(self::$styles[$classname])) return ''; + return 'style="'.self::$styles[$classname].'"'; + }else{ + return 'class="'.$classname.'"'; + } + } +} + +/** + * Additions by Axel Boldt follow, partly taken from diff.php, phpwiki-1.3.3 + * + */ + +define('NBSP', "\xC2\xA0"); // utf-8 non-breaking space. + +class _HWLDF_WordAccumulator { + + function __construct() { + $this->_lines = array(); + $this->_line = ''; + $this->_group = ''; + $this->_tag = ''; + } + + function _flushGroup($new_tag) { + if ($this->_group !== '') { + if ($this->_tag == 'mark') + $this->_line .= '<strong '.HTMLDiff::css('diff-mark').'>'.$this->_escape($this->_group).'</strong>'; + elseif ($this->_tag == 'add') + $this->_line .= '<span '.HTMLDiff::css('diff-addedline').'>'.$this->_escape($this->_group).'</span>'; + elseif ($this->_tag == 'del') + $this->_line .= '<span '.HTMLDiff::css('diff-deletedline').'><del>'.$this->_escape($this->_group).'</del></span>'; + else + $this->_line .= $this->_escape($this->_group); + } + $this->_group = ''; + $this->_tag = $new_tag; + } + + /** + * @param string $new_tag + */ + function _flushLine($new_tag) { + $this->_flushGroup($new_tag); + if ($this->_line != '') + $this->_lines[] = $this->_line; + $this->_line = ''; + } + + function addWords($words, $tag = '') { + if ($tag != $this->_tag) + $this->_flushGroup($tag); + + foreach ($words as $word) { + // new-line should only come as first char of word. + if ($word == '') + continue; + if ($word[0] == "\n") { + $this->_group .= NBSP; + $this->_flushLine($tag); + $word = substr($word, 1); + } + assert(!strstr($word, "\n")); + $this->_group .= $word; + } + } + + function getLines() { + $this->_flushLine('~done'); + return $this->_lines; + } + + function _escape($str){ + return hsc($str); + } +} + +class WordLevelDiff extends MappedDiff { + + function __construct($orig_lines, $closing_lines) { + list ($orig_words, $orig_stripped) = $this->_split($orig_lines); + list ($closing_words, $closing_stripped) = $this->_split($closing_lines); + + parent::__construct($orig_words, $closing_words, $orig_stripped, $closing_stripped); + } + + function _split($lines) { + if (!preg_match_all('/ ( [^\S\n]+ | [0-9_A-Za-z\x80-\xff]+ | . ) (?: (?!< \n) [^\S\n])? /xsu', + implode("\n", $lines), $m)) { + return array(array(''), array('')); + } + return array($m[0], $m[1]); + } + + function orig() { + $orig = new _HWLDF_WordAccumulator; + + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $orig->addWords($edit->orig); + elseif ($edit->orig) + $orig->addWords($edit->orig, 'mark'); + } + return $orig->getLines(); + } + + function closing() { + $closing = new _HWLDF_WordAccumulator; + + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $closing->addWords($edit->closing); + elseif ($edit->closing) + $closing->addWords($edit->closing, 'mark'); + } + return $closing->getLines(); + } +} + +class InlineWordLevelDiff extends MappedDiff { + + function __construct($orig_lines, $closing_lines) { + list ($orig_words, $orig_stripped) = $this->_split($orig_lines); + list ($closing_words, $closing_stripped) = $this->_split($closing_lines); + + parent::__construct($orig_words, $closing_words, $orig_stripped, $closing_stripped); + } + + function _split($lines) { + if (!preg_match_all('/ ( [^\S\n]+ | [0-9_A-Za-z\x80-\xff]+ | . ) (?: (?!< \n) [^\S\n])? /xsu', + implode("\n", $lines), $m)) { + return array(array(''), array('')); + } + return array($m[0], $m[1]); + } + + function inline() { + $orig = new _HWLDF_WordAccumulator; + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $orig->addWords($edit->closing); + elseif ($edit->type == 'change'){ + $orig->addWords($edit->orig, 'del'); + $orig->addWords($edit->closing, 'add'); + } elseif ($edit->type == 'delete') + $orig->addWords($edit->orig, 'del'); + elseif ($edit->type == 'add') + $orig->addWords($edit->closing, 'add'); + elseif ($edit->orig) + $orig->addWords($edit->orig, 'del'); + } + return $orig->getLines(); + } +} + +/** + * "Unified" diff formatter. + * + * This class formats the diff in classic "unified diff" format. + * + * NOTE: output is plain text and unsafe for use in HTML without escaping. + */ +class UnifiedDiffFormatter extends DiffFormatter { + + function __construct($context_lines = 4) { + $this->leading_context_lines = $context_lines; + $this->trailing_context_lines = $context_lines; + } + + function _block_header($xbeg, $xlen, $ybeg, $ylen) { + if ($xlen != 1) + $xbeg .= "," . $xlen; + if ($ylen != 1) + $ybeg .= "," . $ylen; + return "@@ -$xbeg +$ybeg @@\n"; + } + + function _added($lines) { + $this->_lines($lines, "+"); + } + function _deleted($lines) { + $this->_lines($lines, "-"); + } + function _changed($orig, $final) { + $this->_deleted($orig); + $this->_added($final); + } +} + +/** + * Wikipedia Table style diff formatter. + * + */ +class TableDiffFormatter extends DiffFormatter { + var $colspan = 2; + + function __construct() { + $this->leading_context_lines = 2; + $this->trailing_context_lines = 2; + } + + /** + * @param Diff $diff + * @return string + */ + function format($diff) { + // Preserve whitespaces by converting some to non-breaking spaces. + // Do not convert all of them to allow word-wrap. + $val = parent::format($diff); + $val = str_replace(' ','  ', $val); + $val = preg_replace('/ (?=<)|(?<=[ >]) /', ' ', $val); + return $val; + } + + function _pre($text){ + $text = htmlspecialchars($text); + return $text; + } + + function _block_header($xbeg, $xlen, $ybeg, $ylen) { + global $lang; + $l1 = $lang['line'].' '.$xbeg; + $l2 = $lang['line'].' '.$ybeg; + $r = '<tr><td '.HTMLDiff::css('diff-blockheader').' colspan="'.$this->colspan.'">'.$l1.":</td>\n". + '<td '.HTMLDiff::css('diff-blockheader').' colspan="'.$this->colspan.'">'.$l2.":</td>\n". + "</tr>\n"; + return $r; + } + + function _start_block($header) { + print($header); + } + + function _end_block() { + } + + function _lines($lines, $prefix=' ', $color="white") { + } + + function addedLine($line,$escaped=false) { + if (!$escaped){ + $line = $this->_escape($line); + } + return '<td '.HTMLDiff::css('diff-lineheader').'>+</td>'. + '<td '.HTMLDiff::css('diff-addedline').'>' . $line.'</td>'; + } + + function deletedLine($line,$escaped=false) { + if (!$escaped){ + $line = $this->_escape($line); + } + return '<td '.HTMLDiff::css('diff-lineheader').'>-</td>'. + '<td '.HTMLDiff::css('diff-deletedline').'>' . $line.'</td>'; + } + + function emptyLine() { + return '<td colspan="'.$this->colspan.'"> </td>'; + } + + function contextLine($line) { + return '<td '.HTMLDiff::css('diff-lineheader').'> </td>'. + '<td '.HTMLDiff::css('diff-context').'>'.$this->_escape($line).'</td>'; + } + + function _added($lines) { + $this->_addedLines($lines,false); + } + + function _addedLines($lines,$escaped=false){ + foreach ($lines as $line) { + print('<tr>' . $this->emptyLine() . $this->addedLine($line,$escaped) . "</tr>\n"); + } + } + + function _deleted($lines) { + foreach ($lines as $line) { + print('<tr>' . $this->deletedLine($line) . $this->emptyLine() . "</tr>\n"); + } + } + + function _context($lines) { + foreach ($lines as $line) { + print('<tr>' . $this->contextLine($line) . $this->contextLine($line) . "</tr>\n"); + } + } + + function _changed($orig, $closing) { + $diff = new WordLevelDiff($orig, $closing); // this escapes the diff data + $del = $diff->orig(); + $add = $diff->closing(); + + while ($line = array_shift($del)) { + $aline = array_shift($add); + print('<tr>' . $this->deletedLine($line,true) . $this->addedLine($aline,true) . "</tr>\n"); + } + $this->_addedLines($add,true); # If any leftovers + } + + function _escape($str) { + return hsc($str); + } +} + +/** + * Inline style diff formatter. + * + */ +class InlineDiffFormatter extends DiffFormatter { + var $colspan = 2; + + function __construct() { + $this->leading_context_lines = 2; + $this->trailing_context_lines = 2; + } + + /** + * @param Diff $diff + * @return string + */ + function format($diff) { + // Preserve whitespaces by converting some to non-breaking spaces. + // Do not convert all of them to allow word-wrap. + $val = parent::format($diff); + $val = str_replace(' ','  ', $val); + $val = preg_replace('/ (?=<)|(?<=[ >]) /', ' ', $val); + return $val; + } + + function _pre($text){ + $text = htmlspecialchars($text); + return $text; + } + + function _block_header($xbeg, $xlen, $ybeg, $ylen) { + global $lang; + if ($xlen != 1) + $xbeg .= "," . $xlen; + if ($ylen != 1) + $ybeg .= "," . $ylen; + $r = '<tr><td colspan="'.$this->colspan.'" '.HTMLDiff::css('diff-blockheader').'>@@ '.$lang['line']." -$xbeg +$ybeg @@"; + $r .= ' <span '.HTMLDiff::css('diff-deletedline').'><del>'.$lang['deleted'].'</del></span>'; + $r .= ' <span '.HTMLDiff::css('diff-addedline').'>'.$lang['created'].'</span>'; + $r .= "</td></tr>\n"; + return $r; + } + + function _start_block($header) { + print($header."\n"); + } + + function _end_block() { + } + + function _lines($lines, $prefix=' ', $color="white") { + } + + function _added($lines) { + foreach ($lines as $line) { + print('<tr><td '.HTMLDiff::css('diff-lineheader').'> </td><td '.HTMLDiff::css('diff-addedline').'>'. $this->_escape($line) . "</td></tr>\n"); + } + } + + function _deleted($lines) { + foreach ($lines as $line) { + print('<tr><td '.HTMLDiff::css('diff-lineheader').'> </td><td '.HTMLDiff::css('diff-deletedline').'><del>' . $this->_escape($line) . "</del></td></tr>\n"); + } + } + + function _context($lines) { + foreach ($lines as $line) { + print('<tr><td '.HTMLDiff::css('diff-lineheader').'> </td><td '.HTMLDiff::css('diff-context').'>'. $this->_escape($line) ."</td></tr>\n"); + } + } + + function _changed($orig, $closing) { + $diff = new InlineWordLevelDiff($orig, $closing); // this escapes the diff data + $add = $diff->inline(); + + foreach ($add as $line) + print('<tr><td '.HTMLDiff::css('diff-lineheader').'> </td><td>'.$line."</td></tr>\n"); + } + + function _escape($str) { + return hsc($str); + } +} + +/** + * A class for computing three way diffs. + * + * @author Geoffrey T. Dairiki <dairiki@dairiki.org> + */ +class Diff3 extends Diff { + + /** + * Conflict counter. + * + * @var integer + */ + var $_conflictingBlocks = 0; + + /** + * Computes diff between 3 sequences of strings. + * + * @param array $orig The original lines to use. + * @param array $final1 The first version to compare to. + * @param array $final2 The second version to compare to. + */ + function __construct($orig, $final1, $final2) { + $engine = new _DiffEngine(); + + $this->_edits = $this->_diff3($engine->diff($orig, $final1), + $engine->diff($orig, $final2)); + } + + /** + * Returns the merged lines + * + * @param string $label1 label for first version + * @param string $label2 label for second version + * @param string $label3 separator between versions + * @return array lines of the merged text + */ + function mergedOutput($label1='<<<<<<<',$label2='>>>>>>>',$label3='=======') { + $lines = array(); + foreach ($this->_edits as $edit) { + if ($edit->isConflict()) { + /* FIXME: this should probably be moved somewhere else. */ + $lines = array_merge($lines, + array($label1), + $edit->final1, + array($label3), + $edit->final2, + array($label2)); + $this->_conflictingBlocks++; + } else { + $lines = array_merge($lines, $edit->merged()); + } + } + + return $lines; + } + + /** + * @access private + * + * @param array $edits1 + * @param array $edits2 + * + * @return array + */ + function _diff3($edits1, $edits2) { + $edits = array(); + $bb = new _Diff3_BlockBuilder(); + + $e1 = current($edits1); + $e2 = current($edits2); + while ($e1 || $e2) { + if ($e1 && $e2 && is_a($e1, '_DiffOp_copy') && is_a($e2, '_DiffOp_copy')) { + /* We have copy blocks from both diffs. This is the (only) + * time we want to emit a diff3 copy block. Flush current + * diff3 diff block, if any. */ + if ($edit = $bb->finish()) { + $edits[] = $edit; + } + + $ncopy = min($e1->norig(), $e2->norig()); + assert($ncopy > 0); + $edits[] = new _Diff3_Op_copy(array_slice($e1->orig, 0, $ncopy)); + + if ($e1->norig() > $ncopy) { + array_splice($e1->orig, 0, $ncopy); + array_splice($e1->closing, 0, $ncopy); + } else { + $e1 = next($edits1); + } + + if ($e2->norig() > $ncopy) { + array_splice($e2->orig, 0, $ncopy); + array_splice($e2->closing, 0, $ncopy); + } else { + $e2 = next($edits2); + } + } else { + if ($e1 && $e2) { + if ($e1->orig && $e2->orig) { + $norig = min($e1->norig(), $e2->norig()); + $orig = array_splice($e1->orig, 0, $norig); + array_splice($e2->orig, 0, $norig); + $bb->input($orig); + } + + if (is_a($e1, '_DiffOp_copy')) { + $bb->out1(array_splice($e1->closing, 0, $norig)); + } + + if (is_a($e2, '_DiffOp_copy')) { + $bb->out2(array_splice($e2->closing, 0, $norig)); + } + } + + if ($e1 && ! $e1->orig) { + $bb->out1($e1->closing); + $e1 = next($edits1); + } + if ($e2 && ! $e2->orig) { + $bb->out2($e2->closing); + $e2 = next($edits2); + } + } + } + + if ($edit = $bb->finish()) { + $edits[] = $edit; + } + + return $edits; + } +} + +/** + * @author Geoffrey T. Dairiki <dairiki@dairiki.org> + * + * @access private + */ +class _Diff3_Op { + + function __construct($orig = false, $final1 = false, $final2 = false) { + $this->orig = $orig ? $orig : array(); + $this->final1 = $final1 ? $final1 : array(); + $this->final2 = $final2 ? $final2 : array(); + } + + function merged() { + if (!isset($this->_merged)) { + if ($this->final1 === $this->final2) { + $this->_merged = &$this->final1; + } elseif ($this->final1 === $this->orig) { + $this->_merged = &$this->final2; + } elseif ($this->final2 === $this->orig) { + $this->_merged = &$this->final1; + } else { + $this->_merged = false; + } + } + + return $this->_merged; + } + + function isConflict() { + return $this->merged() === false; + } + +} + +/** + * @author Geoffrey T. Dairiki <dairiki@dairiki.org> + * + * @access private + */ +class _Diff3_Op_copy extends _Diff3_Op { + + function __construct($lines = false) { + $this->orig = $lines ? $lines : array(); + $this->final1 = &$this->orig; + $this->final2 = &$this->orig; + } + + function merged() { + return $this->orig; + } + + function isConflict() { + return false; + } +} + +/** + * @author Geoffrey T. Dairiki <dairiki@dairiki.org> + * + * @access private + */ +class _Diff3_BlockBuilder { + + function __construct() { + $this->_init(); + } + + function input($lines) { + if ($lines) { + $this->_append($this->orig, $lines); + } + } + + function out1($lines) { + if ($lines) { + $this->_append($this->final1, $lines); + } + } + + function out2($lines) { + if ($lines) { + $this->_append($this->final2, $lines); + } + } + + function isEmpty() { + return !$this->orig && !$this->final1 && !$this->final2; + } + + function finish() { + if ($this->isEmpty()) { + return false; + } else { + $edit = new _Diff3_Op($this->orig, $this->final1, $this->final2); + $this->_init(); + return $edit; + } + } + + function _init() { + $this->orig = $this->final1 = $this->final2 = array(); + } + + function _append(&$array, $lines) { + array_splice($array, sizeof($array), 0, $lines); + } +} + +//Setup VIM: ex: et ts=4 : |