properly handle invalid regular expressions supplied when testing filters, add some additional regexp checks (closes #427)

classes/pref_filters.php

@@ -33,6 +33,16 @@ class Pref_Filters extends Protected_Handler {
 		else
 			$feed = -4;
 
+		$regexp_valid = preg_match('/' . $filter['reg_exp'] . '/',
+			$filter['reg_exp']) !== FALSE;
+
+		print __("Articles matching this filter:");
+
+		print "<div class=\"inactiveFeedHolder\">";
+		print "<table width=\"100%\" cellspacing=\"0\" id=\"prefErrorFeedList\">";
+
+		if ($regexp_valid) {
+
 			$feed_title = getFeedTitle($this->link, $feed);
 
 			$qfh_ret = queryFeedHeadlines($this->link, $cat_filter ? $cat_id : $feed,
@@ -44,11 +54,6 @@ class Pref_Filters extends Protected_Handler {
 			$articles = array();
 			$found = 0;
 
-		print __("Articles matching this filter:");
-
-		print "<div class=\"inactiveFeedHolder\">";
-		print "<table width=\"100%\" cellspacing=\"0\" id=\"prefErrorFeedList\">";
-
 			while ($line = db_fetch_assoc($result)) {
 
 				$entry_timestamp = strtotime($line["updated"]);
@@ -83,6 +88,11 @@ class Pref_Filters extends Protected_Handler {
 				print "<tr><td align='center'>" .
 					__("No articles matching this filter has been found.") . "</td></tr>";
 			}
+		} else {
+			print "<tr><td align='center' class='error'>" .
+				__("Invalid regular expression.") . "</td></tr>";
+
+		}
 
 		print "</table>";
 		print "</div>";

include/functions.php

@@ -4973,6 +4973,11 @@
 	function filter_to_sql($filter) {
 		$query = "";
 
+		$regexp_valid = preg_match('/' . $filter['reg_exp'] . '/',
+			$filter['reg_exp']) !== FALSE;
+
+		if ($regexp_valid) {
+
 			if (DB_TYPE == "pgsql")
 				$reg_qpart = "~";
 			else
@@ -5028,8 +5033,10 @@
 				$query .= " AND ";
 			}
 
-
 			return $query;
+		} else {
+			return false;
+		}
 	}
 
 	// Status codes:

js/functions.js

@@ -982,6 +982,24 @@ function quickAddFilter() {
 			test: function() {
 				if (this.validate()) {
 
+					var query = "?op=rpc&method=verifyRegexp&reg_exp=" +
+						param_escape(dialog.attr('value').reg_exp);
+
+					notify_progress("Verifying regular expression...");
+
+					new Ajax.Request("backend.php",	{
+						parameters: query,
+						onComplete: function(transport) {
+							var reply = JSON.parse(transport.responseText);
+
+							if (reply) {
+								notify('');
+
+								if (!reply['status']) {
+									alert("Invalid regular expression.");
+									return;
+								} else {
+
 									if (dijit.byId("filterTestDlg"))
 										dijit.byId("filterTestDlg").destroyRecursive();
 
@@ -994,7 +1012,9 @@ function quickAddFilter() {
 									});
 
 									tdialog.show();
-
+								}
+							}
+					}});
 				}
 			},
 			execute: function() {
@@ -1014,7 +1034,7 @@ function quickAddFilter() {
 								notify('');
 
 								if (!reply['status']) {
-									alert("Match regular expression seems to be invalid.");
+									alert("Invalid regular expression.");
 									return;
 								} else {
 									notify_progress("Saving data...", true);

tt-rss.css

@@ -1407,3 +1407,7 @@ a.bookmarklet {
 	padding : 1em;
 	color : gray;
 }
+
+td.error { 
+	color : red;
+}