Rewrite Trolltechs Cache implementation.

	-Update the used timestamp on access
	-Do not play silly games with ConfigPrivate pointers
	 copying them is enough

In write save the old config group and restore it after
writing it

1 files changed, 109 insertions, 129 deletions

diff --git a/library/config.cpp b/library/config.cpp
index f68c336..e9cae4c 100644
--- a/library/config.cpp
+++ b/library/config.cpp
@@ -1,333 +1,313 @@
 /**********************************************************************
 ** Copyright (C) 2000,2004 Trolltech AS.  All rights reserved.
 **
 ** This file is part of Qtopia Environment.
 **
 ** This file may be distributed and/or modified under the terms of the
 ** GNU General Public License version 2 as published by the Free Software
 ** Foundation and appearing in the file LICENSE.GPL included in the
 ** packaging of this file.
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ** See http://www.trolltech.com/gpl/ for GPL licensing information.
 **
 ** Contact info@trolltech.com if any conditions of this licensing are
 ** not clear to you.
 **
 **********************************************************************/
 
 #include <qdir.h>
 #include <qmessagebox.h>
 #if QT_VERSION <= 230 && defined(QT_NO_CODECS)
 #include <qtextcodec.h>
 #endif
 #include <qtextstream.h>
 
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/time.h>
 #include <fcntl.h>
 #include <stdlib.h>
 #include <time.h>
 #include <unistd.h>
 
 #define QTOPIA_INTERNAL_LANGLIST
 #include "config.h"
 #include "global.h"
 #include "qpeapplication.h"
 
 
 /*
  * Internal Class
  */
 class ConfigPrivate {
 public:
     ConfigPrivate() : multilang(FALSE) {}
     ConfigPrivate(const ConfigPrivate& o) :
         trfile(o.trfile),
         trcontext(o.trcontext),
         multilang(o.multilang)
     {}
     ConfigPrivate& operator=(const ConfigPrivate& o)
     {
         trfile = o.trfile;
         trcontext = o.trcontext;
         multilang = o.multilang;
         return *this;
     }
 
     QString trfile;
     QCString trcontext;
     bool multilang;
 };
 
 /////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////
 
 #ifndef Q_OS_WIN32
 
 //#define DEBUG_CONFIG_CACHE
-
-const int CONFIG_CACHE_SIZE = 8192;
-const int CONFIG_CACHE_TIMEOUT = 1000;
-
 class ConfigData
 {
 public:
-    ConfigData(const ConfigData& o) :
-        cfg(o.cfg),
-        priv(o.priv ? new ConfigPrivate(*o.priv) : 0),
-        mtime(o.mtime),
-        size(o.size),
-        used(o.used)
-    { }
-
-    ConfigData& operator=(const ConfigData& o)
+    ConfigData() {}
+    ConfigData( const ConfigGroupMap& cf, const ConfigPrivate& pri,
+                struct stat sbuf )
+        : cfg( cf ), priv( pri ), mtime( sbuf.st_mtime ),
+          size( sbuf.st_size )
     {
-        cfg = o.cfg;
-        delete priv;
-        priv = o.priv ? new ConfigPrivate(*o.priv) : 0;
-        mtime = o.mtime;
-        size = o.size;
-        used = o.used;
-        return *this;
+            gettimeofday(&used, 0 );
     }
 
-    ConfigData() : priv(0) {}
-    ~ConfigData() { delete priv; }
-
     ConfigGroupMap cfg;
-    ConfigPrivate *priv; // Owned by this object
+    ConfigPrivate priv; // Owned by this object
     time_t mtime;
     unsigned int size;
     struct timeval used;
 };
 
-class ConfigCache : public QObject
-{
-public:
-    ConfigCache();
 
-    void insert(const QString &filename, const ConfigGroupMap &cfg, const ConfigPrivate* priv);
-    bool find(const QString &filename, ConfigGroupMap &cfg, ConfigPrivate*& priv);
-    void remove(const QString &filename);
+class ConfigCache : public QObject {
+public:
+    static ConfigCache* instance();
 
+    void insert( const QString& fileName, const ConfigGroupMap& cfg,
+                 const ConfigPrivate *priv );
+    bool find(const QString& fileName, ConfigGroupMap& cfg,
+              ConfigPrivate** priv );
 protected:
     void timerEvent(QTimerEvent *);
 
 private:
+    ConfigCache();
+    void remove( const QString& fileName );
     void removeLru();
 
-    QMap<QString, ConfigData> configData;
-    unsigned int totalsize;
-    int tid;
+private:
+    QMap<QString, ConfigData> m_cached;
+    unsigned int m_totalSize;
+    int m_tid;
+private:
+    static ConfigCache* m_inst;
+    static const unsigned int CONFIG_CACHE_SIZE = 8192;
+    static const unsigned int CONFIG_CACHE_TIMEOUT = 1000;
 };
 
-ConfigCache::ConfigCache() : QObject(), totalsize(0), tid(0)
-{
+ConfigCache* ConfigCache::m_inst = 0;
+/*
+ * get destroyed when qApp gets destroyed
+ */
+ConfigCache::ConfigCache() : QObject( qApp ), m_totalSize( 0 ), m_tid( 0 ) {}
+ConfigCache* ConfigCache::instance() {
+    if ( !m_inst )
+        m_inst = new ConfigCache();
+
+    return m_inst;
 }
 
-void ConfigCache::insert(const QString &filename, const ConfigGroupMap &cfg, const ConfigPrivate* priv)
-{
-    // use stat() rather than QFileInfo for speed.
-    struct stat sbuf;
-    stat(filename.local8Bit().data(), &sbuf);
-
-    if (sbuf.st_size < CONFIG_CACHE_SIZE/2) {
-        ConfigData data;
-        data.cfg = cfg;
-        data.priv = priv ? new ConfigPrivate(*priv) : 0;
-        data.mtime = sbuf.st_mtime;
-        data.size = sbuf.st_size;
-        gettimeofday(&data.used, 0);
+void ConfigCache::remove( const QString& fileName ) {
+    QMap<QString, ConfigData>::Iterator it = m_cached.find( fileName );
 
-        remove(filename);
-        configData.insert(filename, data);
+    if ( it == m_cached.end() )
+        return;
 
-        totalsize += data.size;
-#ifdef DEBUG_CONFIG_CACHE
-        qDebug("++++++ insert %s", filename.latin1());
-#endif
+    m_totalSize -= (*it).size;
+    m_cached.remove( it );
     }
 
-    if (totalsize > (uint)CONFIG_CACHE_SIZE) {
-        // We'll delay deleting anything until later.
-        // This lets us grow quite large during some operations,
-        // but we'll be reduced to a decent size later.
-        // This works well with the main use case - app startup.
-        if (!tid)
-            tid = startTimer(CONFIG_CACHE_TIMEOUT);
-    }
+void ConfigCache::removeLru() {
+    QMap<QString, ConfigData>::Iterator it  = m_cached.begin();
+    QMap<QString, ConfigData>::Iterator lru = it;
+    ++it;
+    for (; it != m_cached.end(); ++it)
+        if ((*it).used.tv_sec < (*lru).used.tv_sec ||
+            ((*it).used.tv_sec == (*lru).used.tv_sec &&
+             (*it).used.tv_usec < (*lru).used.tv_usec))
+            lru = it;
+
+    qWarning( "Removing item" );
+    m_totalSize -= (*lru).size;
+    m_cached.remove(lru);
 }
 
-bool ConfigCache::find(const QString &filename, ConfigGroupMap &cfg, ConfigPrivate*& priv)
-{
-    QMap<QString, ConfigData>::Iterator it = configData.find(filename);
-    if (it != configData.end()) {
-        ConfigData data = *it;
-        // use stat() rather than QFileInfo for speed.
-        struct stat sbuf;
-        stat(filename.local8Bit().data(), &sbuf);
+void ConfigCache::timerEvent( QTimerEvent* ) {
+    while ( m_totalSize > CONFIG_CACHE_SIZE )
+        removeLru();
 
-        if (data.mtime == sbuf.st_mtime && (int)data.size == sbuf.st_size) {
-            cfg = data.cfg;
-            delete priv;
-            priv = data.priv ? new ConfigPrivate(*data.priv) : 0;
-            gettimeofday(&data.used, 0);
-#ifdef DEBUG_CONFIG_CACHE
-            qDebug("******* Cache hit: %s", filename.latin1());
-#endif
-            return TRUE;
-        }
+    killTimer(m_tid);
+    m_tid = 0;
     }
 
-#ifdef DEBUG_CONFIG_CACHE
-    qDebug("------- Cache miss: %s", filename.latin1());
-#endif
+void ConfigCache::insert( const QString& fileName, const ConfigGroupMap& cfg,
+                          const ConfigPrivate* _priv ) {
 
-    return FALSE;
-}
 
-void ConfigCache::remove(const QString &filename)
-{
-    QMap<QString, ConfigData>::Iterator it = configData.find(filename);
-    if (it != configData.end()) {
-        totalsize -= (*it).size;
-        configData.remove(it);
-    }
-}
+    struct stat sbuf;
+    ::stat( QFile::encodeName(fileName), &sbuf );
+    if ( static_cast<unsigned int>(sbuf.st_size) >= CONFIG_CACHE_SIZE>>1)
+        return;
 
-void ConfigCache::timerEvent(QTimerEvent *)
-{
-#ifdef DEBUG_CONFIG_CACHE
-    qDebug( "cache size: %d", totalsize);
-#endif
-    while (totalsize > (uint)CONFIG_CACHE_SIZE)
-        removeLru();
-    killTimer(tid);
-    tid = 0;
-}
+    /*
+     * remove the old version and use the new one
+     */
+    ConfigPrivate priv = _priv ? *_priv : ConfigPrivate();
+    ConfigData data( cfg, priv, sbuf );
+    m_totalSize += data.size;
 
-void ConfigCache::removeLru()
-{
-    QMap<QString, ConfigData>::Iterator it = configData.begin();
-    QMap<QString, ConfigData>::Iterator lru = it;
-    ++it;
-    for (; it != configData.end(); ++it) {
-        if ((*it).used.tv_sec < (*lru).used.tv_sec ||
-            ((*it).used.tv_sec == (*lru).used.tv_sec &&
-             (*it).used.tv_usec < (*lru).used.tv_usec))
-            lru = it;
-    }
+    remove( fileName );
+    m_cached.insert( fileName, data );
 
-#ifdef DEBUG_CONFIG_CACHE
-    qDebug("Cache full, removing: %s", lru.key().latin1());
-#endif
-    totalsize -= (*lru).size;
-    configData.remove(lru);
+    /*
+     * we've overcommited allocation, let us clean up
+     * soon
+     */
+    if ( m_totalSize >= CONFIG_CACHE_SIZE )
+        if ( !m_tid )
+            m_tid = startTimer(CONFIG_CACHE_TIMEOUT);
 }
 
-static ConfigCache *qpe_configCache = 0;
+bool ConfigCache::find( const QString& fileName, ConfigGroupMap& cfg,
+                        ConfigPrivate **ppriv ) {
+    QMap<QString, ConfigData>::Iterator it = m_cached.find(fileName);
+    if (it != m_cached.end()) {
+        ConfigData &data = *it;
+        struct stat sbuf;
+        ::stat(QFile::encodeName( fileName ), &sbuf);
 
-#endif /* Q_OS_WIN32 */
+        if (data.mtime == sbuf.st_mtime && (int)data.size == sbuf.st_size) {
+            cfg = data.cfg;
 
+            /*
+             * null pointer
+             */
+            if ( *ppriv == 0 )
+                *ppriv = new ConfigPrivate( data.priv );
+            **ppriv = data.priv;
+            gettimeofday(&data.used, 0);
 
-// ==========================================================================
+            return true;
+        }
+    }
+
+    return false;
+}
+
+#endif
 
 
 /*!
   \internal
 */
 QString Config::configFilename(const QString& name, Domain d)
 {
     switch (d) {
 	case File:
 	    return name;
 	case User: {
 	    QDir dir = (QString(getenv("HOME")) + "/Settings");
 	    if ( !dir.exists() )
 		mkdir(dir.path().local8Bit(),0700);
 	    return dir.path() + "/" + name + ".conf";
 	}
     }
     return name;
 }
 
 /* This cannot be made public because of binary compat issues */
 void Config::read( QTextStream &s )
 {
 #if QT_VERSION <= 230 && defined(QT_NO_CODECS)
     // The below should work, but doesn't in Qt 2.3.0
     s.setCodec( QTextCodec::codecForMib( 106 ) );
 #else
     s.setEncoding( QTextStream::UnicodeUTF8 );
 #endif
 
     QStringList list = QStringList::split('\n', s.read() );
 
     for ( QStringList::Iterator it = list.begin(); it != list.end(); ++it ) {
         if ( !parse( *it ) ) {
             git = groups.end();
             return;
         }
     }
 }
 
 /*!
   \class Config config.h
   \brief The Config class provides for saving application cofniguration state.
 
   You should keep a Config in existence only while you do not want others
   to be able to change the state. There is no locking currently, but there
   may be in the future.
 */
 
 /*!
   \enum Config::ConfigGroup
   \internal
 */
 
 /*!
   \enum Config::Domain
 
   \value File
   \value User
 
   See Config for details.
 */
 
 /*!
   Constructs a config that will load or create a configuration with the
   given \a name in the given \a domain.
 
   You must call setGroup() before doing much else with the Config.
 
   In the default Domain, \e User,
   the configuration is user-specific. \a name should not contain "/" in
   this case, and in general should be the name of the C++ class that is
   primarily responsible for maintaining the configuration.
 
   In the File Domain, \a name is an absolute filename.
 */
 Config::Config( const QString &name, Domain domain )
     : filename( configFilename(name,domain) )
 {
     git = groups.end();
     d = 0;
     read();
 }
 
 
 // Sharp ROM compatibility
 Config::Config ( const QString &name, bool what )
 	: filename( configFilename(name,what ? User : File) )
 {
     git = groups.end();
     d = 0;
     read();
 }
 
 /*!
   Writes any changes to disk and destroys the in-memory object.
@@ -602,310 +582,310 @@ QString Config::readEntryCrypt( const QString &key, const QString &deflt )
 /*!
   \fn QString Config::readEntryDirect( const QString &key, const QString &deflt ) const
   \internal
 */
 
 /*!
   \internal
   For compatibility, non-const version.
 */
 QString Config::readEntryDirect( const QString &key, const QString &deflt )
 {
     if ( git == groups.end() ) {
 	//qWarning( "no group set" );
 	return deflt;
     }
     ConfigGroup::ConstIterator it = ( *git ).find( key );
     if ( it != ( *git ).end() )
 	return *it;
     else
 	return deflt;
 }
 
 /*!
   \fn int Config::readNumEntry( const QString &key, int deflt ) const
   Reads a numeric entry stored with \a key, defaulting to \a deflt if there is no entry.
 */
 
 /*!
   \internal
   For compatibility, non-const version.
 */
 int Config::readNumEntry( const QString &key, int deflt )
 {
     QString s = readEntry( key );
     if ( s.isEmpty() )
 	return deflt;
     else
 	return s.toInt();
 }
 
 /*!
   \fn bool Config::readBoolEntry( const QString &key, bool deflt ) const
   Reads a bool entry stored with \a key, defaulting to \a deflt if there is no entry.
 */
 
 /*!
   \internal
   For compatibility, non-const version.
 */
 bool Config::readBoolEntry( const QString &key, bool deflt )
 {
     QString s = readEntry( key );
     if ( s.isEmpty() )
 	return deflt;
     else
 	return (bool)s.toInt();
 }
 
 /*!
   \fn QStringList Config::readListEntry( const QString &key, const QChar &sep ) const
   Reads a string list entry stored with \a key, and with \a sep as the separator.
 */
 
 /*!
   \internal
   For compatibility, non-const version.
 */
 QStringList Config::readListEntry( const QString &key, const QChar &sep )
 {
     QString s = readEntry( key );
     if ( s.isEmpty() )
 	return QStringList();
     else
 	return QStringList::split( sep, s );
 }
 
 /*!
   Removes all entries from the current group.
 */
 void Config::clearGroup()
 {
     if ( git == groups.end() ) {
 	qWarning( "no group set" );
 	return;
     }
     if ( !(*git).isEmpty() ) {
 	( *git ).clear();
 	changed = TRUE;
     }
 }
 
 /*!
   \internal
 */
 void Config::write( const QString &fn )
 {
+    QString oldGroup = git.key();
+
     QString strNewFile;
     if ( !fn.isEmpty() )
 	filename = fn;
     strNewFile = filename + ".new";
 
     QFile f( strNewFile );
     if ( !f.open( IO_WriteOnly|IO_Raw ) ) {
 	qWarning( "could not open for writing `%s'", strNewFile.latin1() );
 	git = groups.end();
 	return;
     }
 
     QString str;
     QCString cstr;
     QMap< QString, ConfigGroup >::Iterator g_it = groups.begin();
 
     for ( ; g_it != groups.end(); ++g_it ) {
         str += "[" + g_it.key() + "]\n";
         ConfigGroup::Iterator e_it = ( *g_it ).begin();
         for ( ; e_it != ( *g_it ).end(); ++e_it )
             str += e_it.key() + " = " + *e_it + "\n";
     }
     cstr = str.utf8();
 
     int total_length;
     total_length = f.writeBlock( cstr.data(), cstr.length() );
     if ( total_length != int(cstr.length()) ) {
 	QMessageBox::critical( 0, QObject::tr("Out of Space"),
 			       QObject::tr("There was a problem creating\nConfiguration Information \nfor this program.\n\nPlease free up some space and\ntry again.") );
 	f.close();
 	QFile::remove( strNewFile );
 	return;
     }
 
     f.close();
     // now rename the file...
     if ( rename( strNewFile, filename ) < 0 ) {
 	qWarning( "problem renaming the file %s to %s", strNewFile.latin1(),
 		  filename.latin1() );
         QFile::remove( strNewFile );
         return;
     }
 
 #ifndef Q_OS_WIN32
-    if (qpe_configCache)
-        qpe_configCache->insert(filename, groups, d);
+    ConfigCache::instance()->insert( filename, groups, d );
+    setGroup( oldGroup );
 #endif
     changed = FALSE;
 }
 
 /*!
   Returns whether the Config is in a valid state.
 */
 bool Config::isValid() const
 {
     return groups.end() != git;
 }
 
 /*!
   \internal
 */
 void Config::read()
 {
     changed = FALSE;
 
     QString readFilename(filename);
 
     if ( !QFile::exists(filename) ) {
         bool failed = TRUE;
         QFileInfo fi(filename);
         QString settingsDir = QDir::homeDirPath() + "/Settings";
         if (fi.dirPath(TRUE) == settingsDir) {
         // User setting - see if there is a default in $OPIEDIR/etc/default/
             QString dftlFile = QPEApplication::qpeDir() + "etc/default/" + fi.fileName();
             if (QFile::exists(dftlFile)) {
                 readFilename = dftlFile;
                 failed = FALSE;
             }
         }
         if (failed) {
             git = groups.end();
             return;
         }
     }
 
 #ifndef Q_OS_WIN32
-    if (!qpe_configCache)
-        qpe_configCache = new ConfigCache;
 
-    if (qpe_configCache->find(readFilename, groups, d)) {
+    if (ConfigCache::instance()->find(readFilename, groups, &d)) {
         if ( d && d->multilang ) {
             QStringList l = Global::languageList();
             lang = l[0];
             glang = l[1];
         }
         git = groups.begin();
         return;
     }
 #endif
 
     QFile f( readFilename );
     if ( !f.open( IO_ReadOnly ) ) {
         git = groups.end();
         return;
     }
 
     if (f.getch()!='[') {
         git = groups.end();
         return;
     }
     f.ungetch('[');
 
     QTextStream s( &f );
     read( s );
     f.close();
 
 #ifndef Q_OS_WIN32
-    qpe_configCache->insert(readFilename, groups, d);
+    ConfigCache::instance()->insert(readFilename, groups, d);
 #endif
 }
 
 /*!
   \internal
 */
 bool Config::parse( const QString &l )
 {
     QString line = l.stripWhiteSpace();
     if ( line[ 0 ] == QChar( '[' ) ) {
         QString gname = line;
         gname = gname.remove( 0, 1 );
         if ( gname[ (int)gname.length() - 1 ] == QChar( ']' ) )
             gname = gname.remove( gname.length() - 1, 1 );
         git = groups.insert( gname, ConfigGroup() );
     } else if ( !line.isEmpty() ) {
         if ( git == groups.end() )
             return FALSE;
         int eq = line.find( '=' );
         if ( eq == -1 )
             return FALSE;
         QString key = line.left(eq).stripWhiteSpace();
         QString value = line.mid(eq+1).stripWhiteSpace();
 
         if ( git.key() == "Translation" ) {
             if ( key == "File" ) {
                 if ( !d )
                     d = new ConfigPrivate;
                 d->trfile = value;
             } else if ( key == "Context" ) {
                 if ( !d )
                     d = new ConfigPrivate;
                 d->trcontext = value.latin1();
             } else if ( key.startsWith("Comment") ) {
                 return TRUE; // ignore comment for ts file
             } else {
                 return FALSE; // Unrecognized
             }
         }
 
         int kl = key.length();
         if ( kl > 1 && key[kl-1] == ']' && key[kl-2] != '[' ) {
             // Old-style translation (inefficient)
             if ( !d )
                 d = new ConfigPrivate;
             if ( !d->multilang ) {
                 QStringList l = Global::languageList();
                 lang = l[0];
                 glang = l[1];
                 d->multilang = TRUE;
             }
         }
 
         ( *git ).insert( key, value );
     }
     return TRUE;
 }
 
 
 
 bool Config::hasGroup( const QString& name )const {
     return ( groups. find ( name ) != groups. end ( ));
 };
 
 QStringList Config::groupList()const {
     QStringList sl;
     for ( ConfigGroupMap::ConstIterator it = groups. begin ( ); it != groups. end ( ); ++it )
         sl << it.key();
 
     return sl;
 };
 
 /////////////
 // Qtopia 2.1 Functions
 //
 ////////////
 
 QStringList Config::allGroups()const {
     return groupList();
 }
 
 /*!
   Returns the time stamp for the config identified by \a name.  The
   time stamp represents the time the config was last committed to storage.
   Returns 0 if there is no time stamp available for the config.
 
   A \a domain can optionally be specified and defaults to User.
   See \l{Config()} for details.
 
   First availability: Qtopia 2.0
 */
 long Config::timeStamp(const QString& name, Domain domain)
 {
 #ifdef Q_WS_WIN
     // Too slow (many conversions too and from time_t and QDataTime)
     QDateTime epoch;