diff options
Diffstat (limited to 'inc/fulltext.php')
| -rw-r--r-- | inc/fulltext.php | 79 |
1 files changed, 50 insertions, 29 deletions
diff --git a/inc/fulltext.php b/inc/fulltext.php index b9450c172..fa3ec05d2 100644 --- a/inc/fulltext.php +++ b/inc/fulltext.php @@ -255,7 +255,6 @@ switch ($algorithm) { break; case 'opt2' : - default : // option 2 ... CS 2006-08-25 // above + reduce amount of the file searched $match = array(); @@ -311,15 +310,22 @@ switch ($algorithm) { break; case 'utf8': + default : + $match = array(); $snippets = array(); - $utf8_offset = $offset = 0; + $utf8_offset = $offset = $end = 0; $len = utf8_strlen($text); + for ($cnt=3; $cnt--;) { if (!preg_match('#'.$re.'#iu',$text,$match,PREG_OFFSET_CAPTURE,$offset)) break; list($str,$idx) = $match[0]; + // is it ok to use utf8_substr() -- see bug #891, + // check idx against (2^16)-1 - 400 (100x4 byte utf-8 characters) + if ($idx <= 65135) { + // convert $idx (a byte offset) into a utf8 character offset $utf8_idx = utf8_strlen(substr($text,0,$idx)); $utf8_len = utf8_strlen($str); @@ -328,39 +334,54 @@ switch ($algorithm) { // first look to see if we can go 100 either side, // then drop to 50 adding any excess if the other side can't go to 50, // NOTE: these are byte adjustments and will have to be corrected for utf-8 - $pre = min($utf8_idx-$utf8_offset,100); - $post = min($len-$utf8_idx-$utf8_len,100); + $pre = min($utf8_idx-$utf8_offset,100); + $post = min($len-$utf8_idx-$utf8_len,100); + + if ($pre>50 && $post>50) { + $pre = $post = 50; + } else if ($pre>50) { + $pre = min($pre,100-$post); + } else if ($post>50) { + $post = min($post, 100-$pre); + } else { + // both are less than 50, means the context is the whole string + // make it so and break out of this loop - there is no need for the complex snippet calculations + $snippets = array($text); + break; + } - if ($pre>50 && $post>50) { - $pre = $post = 50; - } else if ($pre>50) { - $pre = min($pre,100-$post); - } else if ($post>50) { - $post = min($post, 100-$pre); - } else { - // both are less than 50, means the context is the whole string - // make it so and break out of this loop - there is no need for the complex snippet calculations - $snippets = array($text); - break; - } + // establish context start and end points, try to append to previous context if possible + $start = $utf8_idx - $pre; + $append = ($start < $end) ? $end : false; // still the end of the previous context snippet + $end = $utf8_idx + $utf8_len + $post; // now set it to the end of this context - // establish context start and end points, try to append to previous context if possible - $start = $idx - $pre; - $append = ($start < $end) ? $end : false; // still the end of the previous context snippet - $end = $idx + $utf8_len + $post; // now set it to the end of this context + if ($append) { + $snippets[count($snippets)-1] .= utf8_substr($text,$append,$end-$append); + } else { + $snippets[] = utf8_substr($text,$start,$end-$start); + } - if ($append) { - $snippets[count($snippets)-1] .= utf8_substr($text,$append,$end-$append); + // set $offset for next match attempt + // substract strlen to avoid splitting a potential search success, this is an approximation as the + // search pattern may match strings of varying length and it will fail if the context snippet + // boundary breaks a matching string longer than the current match + $utf8_offset = $utf8_idx + $post; + $offset = $idx + strlen(utf8_substr($text,$utf8_idx,$post)); + $offset = utf8_correctIdx($text,$offset); } else { - $snippets[] = utf8_substr($text,$start,$end-$start); + // code for strings too large for utf8_substr + // use a larger context number as its bytes not characters + $pre = 70; + $post = min(strlen($text)-$idx-strlen($str), 70); + if ($post < 70) { $pre = 70 - $post; } + + $start = utf8_correctIdx($text,$idx - $pre); + $end = utf8_correctIdx($text, $idx + strlen($str) + $post); + + $snippets[] = substr($text,$start,$end-$start); + $offset = $end - strlen($str); } - // set $offset for next match attempt - // substract strlen to avoid splitting a potential search success, this is an approximation as the - // search pattern may match strings of varying length and it will fail if the context snippet - // boundary breaks a matching string longer than the current match - $utf8_offset = $end - $utf8_len; - $offset = utf8_correctIdx($text,strlen(substr($text,0,$utf8_offset))); } $m = "\1"; $snippets = preg_replace('#'.$re.'#iu',$m.'$1'.$m,$snippets); |