Add a special matcher for ad block filters for host name

Quite a few rules of ad block are just matching domains. Those
are of the form:
||trolltech.com^$options

This patch add a new class to deal with this kind of filter,
AdBlockHostMatcher. Matching a host address is much faster (O(1))
than going through the entire list of rules.

4 files changed, 132 insertions, 1 deletions

diff --git a/src/adblock/adblockhostmatcher.cpp b/src/adblock/adblockhostmatcher.cpp
new file mode 100644
index 00000000..b11dab2c
--- /dev/null
+++ b/src/adblock/adblockhostmatcher.cpp
@@ -0,0 +1,55 @@
+/* ============================================================
+*
+* This file is a part of the rekonq project
+*
+* Copyright (C) 2010 by Benjamin Poulain <ikipou at gmail dot com>
+*
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of
+* the License or (at your option) version 3 or any later version
+* accepted by the membership of KDE e.V. (or its successor approved
+* by the membership of KDE e.V.), which shall act as a proxy
+* defined in Section 14 of version 3 of the license.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+* ============================================================ */
+
+// Self Includes
+#include "adblockhostmatcher.h"
+
+// Rekonq Includes
+#include "rekonq_defines.h"
+
+bool AdBlockHostMatcher::tryAddFilter(const QString &filter)
+{
+    if (filter.startsWith(QL1S("||"))) {
+        QString domain = filter.mid(2);
+
+        const int indexOfFirstSeparator = domain.indexOf(QL1C('^'));
+        if (indexOfFirstSeparator < 0)
+            return false;
+
+        const int indexOfLastDollar = domain.lastIndexOf(QL1C('$'));
+        if (indexOfLastDollar >= 0 && indexOfLastDollar != indexOfFirstSeparator + 1)
+            return false;
+
+        domain = domain.left(indexOfFirstSeparator);
+        if (domain.contains(QL1C('/')) || domain.contains(QL1C('*')))
+            return false;
+
+        domain = domain.toLower();
+        m_hostList.insert(domain);
+        m_hostList.insert(QL1S("www.") + domain);
+        return true;
+    }
+    return false;
+}
diff --git a/src/adblock/adblockhostmatcher.h b/src/adblock/adblockhostmatcher.h
new file mode 100644
index 00000000..0a15bd4e
--- /dev/null
+++ b/src/adblock/adblockhostmatcher.h
@@ -0,0 +1,51 @@
+/* ============================================================
+*
+* This file is a part of the rekonq project
+*
+* Copyright (C) 2010 by Benjamin Poulain <ikipou at gmail dot com>
+*
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License as
+* published by the Free Software Foundation; either version 2 of
+* the License or (at your option) version 3 or any later version
+* accepted by the membership of KDE e.V. (or its successor approved
+* by the membership of KDE e.V.), which shall act as a proxy
+* defined in Section 14 of version 3 of the license.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+* ============================================================ */
+
+#ifndef ADBLOCKHOSTMATCHER_H
+#define ADBLOCKHOSTMATCHER_H
+
+#include <QSet>
+#include <QString>
+
+class AdBlockHostMatcher
+{
+public:
+    // Try to add an adblock filter to this host matcher.
+    // If the filter is not an hostname, the filter is not added
+    // and the method return false;
+    bool tryAddFilter(const QString &filter);
+
+    bool match(const QString &host) const
+    {
+        return m_hostList.contains(host.toLower());
+    }
+
+    void clear() { m_hostList.clear(); }
+
+private:
+    QSet<QString> m_hostList;
+};
+
+#endif // ADBLOCKHOSTMATCHER_H
diff --git a/src/adblock/adblockmanager.cpp b/src/adblock/adblockmanager.cpp
index e0a109f0..600dc5ce 100644
--- a/src/adblock/adblockmanager.cpp
+++ b/src/adblock/adblockmanager.cpp
@@ -67,6 +67,8 @@ void AdBlockManager::loadSettings(bool checkUpdateDate)
     _index = 0;
     _buffer.clear();
 
+    _hostWhiteList.clear();
+    _hostBlackList.clear();
     _whiteList.clear();
     _blackList.clear();
     _hideList.clear();
@@ -133,7 +135,10 @@ void AdBlockManager::loadRules(const QStringList &rules)
         // white rules
         if (stringRule.startsWith(QL1S("@@")))
         {
-            AdBlockRule rule(stringRule.mid(2));
+            const QString filter = stringRule.mid(2);
+            if (_hostWhiteList.tryAddFilter(filter))
+                continue;
+            AdBlockRule rule(filter);
             _whiteList << rule;
             continue;
         }
@@ -145,6 +150,8 @@ void AdBlockManager::loadRules(const QStringList &rules)
             continue;
         }
 
+        if (_hostBlackList.tryAddFilter(stringRule))
+            continue;
         AdBlockRule rule(stringRule);
         _blackList << rule;
     }
@@ -164,8 +171,16 @@ QNetworkReply *AdBlockManager::block(const QNetworkRequest &request, WebPage *pa
     // We compute a lowercase version of the URL so each rule does not
     // have to do it.
     const QString urlStringLowerCase = urlString.toLower();
+    const QString host = request.url().host();
 
     // check white rules before :)
+
+    if (_hostWhiteList.match(host)) {
+        kDebug() << "****ADBLOCK: WHITE RULE (@@) Matched by host matcher: ***********";
+        kDebug() << "UrlString:  " << urlString;
+        return 0;
+    }
+
     foreach(const AdBlockRule &filter, _whiteList)
     {
         if (filter.match(urlString, urlStringLowerCase))
@@ -177,6 +192,13 @@ QNetworkReply *AdBlockManager::block(const QNetworkRequest &request, WebPage *pa
     }
 
     // then check the black ones :(
+    if (_hostBlackList.match(host)) {
+        kDebug() << "****ADBLOCK: BLACK RULE Matched by host matcher: ***********";
+        kDebug() << "UrlString:  " << urlString;
+        AdBlockNetworkReply *reply = new AdBlockNetworkReply(request, urlString, this);
+        return reply;
+    }
+
     foreach(const AdBlockRule &filter, _blackList)
     {
         if (filter.match(urlString, urlStringLowerCase))
diff --git a/src/adblock/adblockmanager.h b/src/adblock/adblockmanager.h
index eae761e0..69548994 100644
--- a/src/adblock/adblockmanager.h
+++ b/src/adblock/adblockmanager.h
@@ -108,6 +108,7 @@
 #include "rekonq_defines.h"
 
 // Local Includes
+#include "adblockhostmatcher.h"
 #include "adblockrule.h"
 
 // KDE Includes
@@ -155,6 +156,8 @@ private:
     bool _isAdblockEnabled;
     bool _isHideAdsEnabled;
 
+    AdBlockHostMatcher _hostBlackList;
+    AdBlockHostMatcher _hostWhiteList;
     AdBlockRuleList _blackList;
     AdBlockRuleList _whiteList;
     QStringList _hideList;