(trunk qt) add code for a favicon cache -- it even shares the GTK+ client's favicon cache directory. :) This isn't plugged in anywhere yet, but will be useful when the filterbar and trackers tab are synced with the GTK+ client.

qt/app.h

@@ -15,6 +15,7 @@
 
 #include <QApplication>
 #include <QTimer>
+#include "favicon.h"
 
 class Prefs;
 class Session;
@@ -33,6 +34,9 @@ class MyApp: public QApplication
     public:
         void raise( );
 
+    public:
+        Favicons favicons;
+
     private:
         Prefs * myPrefs;
         Session * mySession;

qt/favicon.cc

@@ -0,0 +1,142 @@
+/*
+ * This file Copyright (C) 2010 Mnemosyne LLC
+ *
+ * This file is licensed by the GPL version 2.  Works owned by the
+ * Transmission project are granted a special exemption to clause 2(b)
+ * so that the bulk of its code can remain under the MIT license.
+ * This exemption does not extend to derived works not owned by
+ * the Transmission project.
+ *
+ * $Id$
+ */
+
+#include <iostream>
+
+#include <QDesktopServices>
+#include <QDir>
+#include <QNetworkAccessManager>
+#include <QNetworkReply>
+#include <QNetworkRequest>
+
+#include "favicon.h"
+
+/***
+****
+***/
+
+QString
+Favicons :: getCacheDir( )
+{
+    const QString base = QDesktopServices::storageLocation( QDesktopServices::CacheLocation );
+    return QDir( base ).absoluteFilePath( "favicons" );
+};
+
+
+Favicons :: Favicons( )
+{
+    myNAM = new QNetworkAccessManager( );
+    connect( myNAM, SIGNAL(finished(QNetworkReply*)), this, SLOT(onRequestFinished(QNetworkReply*)) );
+}
+
+Favicons :: ~Favicons( )
+{
+    delete myNAM;
+}
+
+/***
+****
+***/
+
+void
+Favicons :: ensureCacheDirHasBeenScanned( )
+{
+    static bool hasBeenScanned = false;
+
+    if( !hasBeenScanned )
+    {
+        hasBeenScanned = true;
+   
+        QDir cacheDir( getCacheDir( ) );
+        cacheDir.mkpath( cacheDir.absolutePath( ) );
+        QStringList files = cacheDir.entryList( QDir::Files|QDir::Readable );
+        foreach( QString file, files ) {
+            QPixmap pixmap;
+            pixmap.load( cacheDir.absoluteFilePath( file ) );
+            if( !pixmap.isNull( ) )
+                myPixmaps.insert( file, pixmap );
+        }
+    }
+}
+
+QString
+Favicons :: getHost( const QUrl& url )
+{
+    QString host = url.host( );
+    const int first_dot = host.indexOf( '.' );
+    const int last_dot = host.lastIndexOf( '.' );
+
+    if( ( first_dot != -1 ) && ( last_dot != -1 ) && ( first_dot != last_dot ) )
+        host.remove( 0, first_dot + 1 );
+
+    return host;
+}
+
+QPixmap
+Favicons :: find( const QUrl& url )
+{
+    ensureCacheDirHasBeenScanned( );
+
+    return myPixmaps[ getHost(url) ];
+}
+
+void
+Favicons :: add( const QUrl& url_in )
+{
+    ensureCacheDirHasBeenScanned( );
+
+    const QString host = getHost(url_in);
+    if( !myPixmaps.contains(host) && !myPending.contains(host) )
+    {
+        const int IMAGE_TYPES = 4;
+        const QString image_types[IMAGE_TYPES] = { "ico", "png", "gif", "jpg" };
+
+        myPending.append( host ); 
+        for( int i=0; i<IMAGE_TYPES; ++i )
+        {
+            QString url( "http://" + host + "/favicon." + image_types[i]);
+            myNAM->get( QNetworkRequest( url ) );
+        }
+    }
+}
+
+void
+Favicons :: onRequestFinished( QNetworkReply * reply )
+{
+    const QString host = reply->url().host();
+
+    myPending.removeAll( host );
+
+    const QByteArray content = reply->readAll( );
+
+    QPixmap pixmap;
+
+    if( !reply->error( ) )
+        pixmap.loadFromData( content );
+
+    if( !pixmap.isNull( ) )
+    {
+        // save it in memory...
+        myPixmaps.insert( host, pixmap );
+
+        // save it on disk...
+        QDir cacheDir( getCacheDir( ) );
+        cacheDir.mkpath( cacheDir.absolutePath( ) );
+        QFile file( cacheDir.absoluteFilePath( host ) );
+        file.open( QIODevice::WriteOnly );
+        file.write( content );
+        file.close( );
+
+        // notify listeners
+        emit pixmapReady( host );
+    }
+}

qt/favicon.h

@@ -0,0 +1,62 @@
+/*
+ * This file Copyright (C) 2010 Mnemosyne LLC
+ *
+ * This file is licensed by the GPL version 2.  Works owned by the
+ * Transmission project are granted a special exemption to clause 2(b)
+ * so that the bulk of its code can remain under the MIT license.
+ * This exemption does not extend to derived works not owned by
+ * the Transmission project.
+ *
+ * $Id$
+ */
+
+#ifndef FAVICON_CACHE_H
+#define FAVICON_CACHE_H
+
+class QNetworkAccessManager;
+class QNetworkReply;
+class QUrl;
+
+#include <QMap>
+#include <QString>
+#include <QStringList>
+#include <QObject>
+#include <QPixmap>
+
+class Favicons: public QObject
+{
+        Q_OBJECT;
+
+    public:
+
+        Favicons();
+        virtual ~Favicons();
+
+        /* returns a cached pixmap, or a NULL pixmap if there's no match in the cache */
+        QPixmap find( const QUrl& url );
+
+        /* this will emit a signal when (if) the icon becomes ready */
+        void add( const QUrl& url );
+
+    signals:
+
+        void pixmapReady( const QString& host );
+
+    private:
+
+        QStringList myPending;
+        QNetworkAccessManager * myNAM;
+        QMap<QString,QPixmap> myPixmaps;
+
+        QString getHost( const QUrl& url );
+
+        QString getCacheDir( );
+
+        void ensureCacheDirHasBeenScanned( );
+
+    private slots:
+
+        void onRequestFinished( QNetworkReply * reply );
+};
+
+#endif

qt/qtr.pro

@@ -30,12 +30,13 @@ TRANSLATIONS += transmission_en.ts transmission_ru.ts
 
 FORMS += mainwin.ui
 RESOURCES += application.qrc
-SOURCES += about.cc app.cc dbus-adaptor.cc details.cc file-tree.cc filters.cc \
-           formatter.cc hig.cc license.cc mainwin.cc make-dialog.cc options.cc \
-           prefs.cc prefs-dialog.cc qticonloader.cc relocate.cc session.cc \
-           session-dialog.cc squeezelabel.cc stats-dialog.cc torrent.cc \
-           torrent-delegate.cc torrent-delegate-min.cc torrent-filter.cc \
-           torrent-model.cc triconpushbutton.cc utils.cc watchdir.cc
+SOURCES += about.cc app.cc dbus-adaptor.cc details.cc favicon.cc file-tree.cc \
+           filters.cc formatter.cc hig.cc license.cc mainwin.cc \
+           make-dialog.cc options.cc prefs.cc prefs-dialog.cc qticonloader.cc \
+           relocate.cc session.cc session-dialog.cc squeezelabel.cc \
+           stats-dialog.cc torrent.cc torrent-delegate.cc \
+           torrent-delegate-min.cc torrent-filter.cc torrent-model.cc \
+           triconpushbutton.cc utils.cc watchdir.cc
 HEADERS += $$replace(SOURCES, .cc, .h)
 HEADERS += speed.h types.h
 

qt/torrent.cc

@@ -19,6 +19,7 @@
 #include <QSet>
 #include <QString>
 #include <QStyle>
+#include <QUrl>
 #include <QVariant>
 
 #include <libtransmission/transmission.h>
@@ -543,9 +544,12 @@ Torrent :: update( tr_benc * d )
         int i = 0;
         QStringList list;
         tr_benc * child;
-        while(( child = tr_bencListChild( trackers, i++ )))
-            if( tr_bencDictFindStr( child, "announce", &str ))
+        while(( child = tr_bencListChild( trackers, i++ ))) {
+            if( tr_bencDictFindStr( child, "announce", &str )) {
+                dynamic_cast<MyApp*>(QApplication::instance())->favicons.add( QUrl(str) );
                 list.append( QString::fromUtf8( str ) );
+            }
+        }
         if( myValues[TRACKERS] != list ) {
             myValues[TRACKERS].setValue( list );
             changed = true;