Add wfDiff function, similar to wfMerge (some copied), used in AbuseFilter extension...

diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index 29e5232..058cbce 100644 (file)
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -1738,6 +1738,11 @@ $wgAntiLockFlags = 0;
  */
 $wgDiff3 = '/usr/bin/diff3';
 
+/**
+ * Path to the GNU diff utility.
+ */
+$wgDiff = '/usr/bin/diff';
+
 /**
  * We can also compress text stored in the 'text' table. If this is set on, new
  * revisions will be compressed on page save if zlib support is available. Any

diff --git a/includes/GlobalFunctions.php b/includes/GlobalFunctions.php
index 8185a7f..7dbe0dd 100644 (file)
--- a/includes/GlobalFunctions.php
+++ b/includes/GlobalFunctions.php
@@ -1178,6 +1178,66 @@ function wfMerge( $old, $mine, $yours, &$result ){
        return ! $conflict;
 }
 
+/**
+ * Returns unified plain-text diff of two texts.
+ * Useful for machine processing of diffs.
+ * @param $before string The text before the changes.
+ * @param $after string The text after the changes.
+ * @param $params string Command-line options for the diff command.
+ * @return string Unified diff of $before and $after
+ */
+function wfDiff( $before, $after, $params = '-u' ) {
+       global $wgDiff;
+
+       # This check may also protect against code injection in
+       # case of broken installations.
+       if(! file_exists( $wgDiff ) ){
+               wfDebug( "diff3 not found\n" );
+               return false;
+       }
+
+       # Make temporary files
+       $td = wfTempDir();
+       $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
+       $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
+
+       fwrite( $oldtextFile, $before ); fclose( $oldtextFile );
+       fwrite( $newtextFile, $after ); fclose( $newtextFile );
+       
+       // Get the diff of the two files
+       $cmd = "$wgDiff " . $params . ' ' .wfEscapeShellArg( $oldtextName, $newtextName );
+       
+       $h = popen( $cmd, 'r' );
+       
+       $diff = '';
+       
+       do {
+               $data = fread( $h, 8192 );
+               if ( strlen( $data ) == 0 ) {
+                       break;
+               }
+               $diff .= $data;
+       } while ( true );
+       
+       // Clean up
+       pclose( $h );
+       unlink( $oldtextName );
+       unlink( $newtextName );
+       
+       // Kill the --- and +++ lines. They're not useful.
+       $diff_lines = explode( "\n", $diff );
+       if (strpos( '---', $diff_lines[0] ) == 0) {
+               unset($diff_lines[0]);
+       }
+       if (strpos( '+++', $diff_lines[1] ) == 0) {
+               unset($diff_lines[1]);
+       }
+       
+       $diff = implode( "\n", $diff_lines );
+       
+       return $diff;
+}
+
 /**
  * @todo document
  */