From bd0f3345a938b35ce6a12f6150373b0955b8dd12 Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Sun, 10 Jul 2011 15:24:15 -0500 Subject: Add Qt3 development HEAD version --- doc/html/networkprotocol-example.html | 364 ++++++++++++++++++++++++++++++++++ 1 file changed, 364 insertions(+) create mode 100644 doc/html/networkprotocol-example.html (limited to 'doc/html/networkprotocol-example.html') diff --git a/doc/html/networkprotocol-example.html b/doc/html/networkprotocol-example.html new file mode 100644 index 0000000..6e90c9e --- /dev/null +++ b/doc/html/networkprotocol-example.html @@ -0,0 +1,364 @@ + + + + + +A simple NNTP implementation + + + + + + + +

A simple NNTP implementation

+ + +

This example shows how to implement your own QNetworkProtocol. The +protocol that was chosen for this example is NTTP. Please note that this +implementation is very simple since it is designed to be an example. It +should not be used as a real NNTP implemention. +

Header file (nntp.h): +

/****************************************************************************
+** $Id: qt/nntp.h   3.3.8   edited Jan 11 14:37 $
+**
+** Copyright (C) 1992-2007 Trolltech ASA.  All rights reserved.
+**
+** This file is part of an example program for Qt.  This example
+** program may be used, distributed and modified without limitation.
+**
+*****************************************************************************/
+
+#ifndef NNTP_H
+#define NNTP_H
+
+#include <qsocket.h>
+#include <qnetworkprotocol.h>
+
+class Nntp : public QNetworkProtocol
+{
+    Q_OBJECT
+
+public:
+    Nntp();
+    virtual ~Nntp();
+    virtual int supportedOperations() const;
+
+protected:
+    virtual void operationListChildren( QNetworkOperation *op );
+    virtual void operationGet( QNetworkOperation *op );
+
+    QSocket *commandSocket;
+    bool connectionReady;
+    bool readGroups;
+    bool readArticle;
+
+private:
+    bool checkConnection( QNetworkOperation *op );
+    void close();
+    void parseGroups();
+    void parseArticle();
+
+protected slots:
+    void hostFound();
+    void connected();
+    void closed();
+    void readyRead();
+    void error( int );
+
+};
+
+#endif
+

+ +

Implementation (nntp.cpp): +

/****************************************************************************
+** $Id: qt/nntp.cpp   3.3.8   edited Jan 11 14:37 $
+**
+** Copyright (C) 1992-2007 Trolltech ASA.  All rights reserved.
+**
+** This file is part of an example program for Qt.  This example
+** program may be used, distributed and modified without limitation.
+**
+*****************************************************************************/
+
+#include "nntp.h"
+#include <qurlinfo.h>
+#include <stdlib.h>
+#include <qurloperator.h>
+#include <qstringlist.h>
+#include <qregexp.h>
+
+Nntp::Nntp()
+    : QNetworkProtocol(), connectionReady( FALSE ),
+      readGroups( FALSE ), readArticle( FALSE )
+{
+    // create the command socket and connect to its signals
+    commandSocket = new QSocket( this );
+    connect( commandSocket, SIGNAL( hostFound() ),
+             this, SLOT( hostFound() ) );
+    connect( commandSocket, SIGNAL( connected() ),
+             this, SLOT( connected() ) );
+    connect( commandSocket, SIGNAL( connectionClosed() ),
+             this, SLOT( closed() ) );
+    connect( commandSocket, SIGNAL( readyRead() ),
+             this, SLOT( readyRead() ) );
+    connect( commandSocket, SIGNAL( error( int ) ),
+             this, SLOT( error( int ) ) );
+}
+
+Nntp::~Nntp()
+{
+    close();
+    delete commandSocket;
+}
+
+void Nntp::operationListChildren( QNetworkOperation * )
+{
+    // create a command
+    QString path = url()->path(), cmd;
+    if ( path.isEmpty() || path == "/" ) {
+        // if the path is empty or we are in the root dir,
+        // we want to read the list of available newsgroups
+        cmd = "list newsgroups\r\n";
+    } else if ( url()->isDir() ) {
+        // if the path is a directory (in our case a news group)
+        // we want to list the articles of this group
+        path = path.replace( "/", "" );
+        cmd = "listgroup " + path + "\r\n";
+    } else
+        return;
+
+    // write the command to the socket
+    commandSocket->writeBlock( cmd.latin1(), cmd.length() );
+    readGroups = TRUE;
+}
+
+void Nntp::operationGet( QNetworkOperation *op )
+{
+    // get the dirPath of the URL (this is our news group)
+    // and the filename (which is the article we want to read)
+    QUrl u( op->arg( 0 ) );
+    QString dirPath = u.dirPath(), file = u.fileName();
+    dirPath = dirPath.replace( "/", "" );
+
+    // go to the group in which the article is
+    QString cmd;
+    cmd = "group " + dirPath + "\r\n";
+    commandSocket->writeBlock( cmd.latin1(), cmd.length() );
+
+    // read the head of the article
+    cmd = "article " + file + "\r\n";
+    commandSocket->writeBlock( cmd.latin1(), cmd.length() );
+    readArticle = TRUE;
+}
+
+bool Nntp::checkConnection( QNetworkOperation * )
+{
+    // we are connected, return TRUE
+    if ( commandSocket->isOpen() && connectionReady )
+        return TRUE;
+
+    // seems that there is no chance to connect
+    if ( commandSocket->isOpen() )
+        return FALSE;
+
+    // don't call connectToHost() if we are already trying to connect
+    if ( commandSocket->state() == QSocket::Connecting )
+        return FALSE;
+
+    // start connecting
+    connectionReady = FALSE;
+    commandSocket->connectToHost( url()->host(),
+                                  url()->port() != -1 ? url()->port() : 119 );
+    return FALSE;
+}
+
+void Nntp::close()
+{
+    // close the command socket
+    if ( commandSocket->isOpen() ) {
+        commandSocket->writeBlock( "quit\r\n", strlen( "quit\r\n" ) );
+        commandSocket->close();
+    }
+}
+
+int Nntp::supportedOperations() const
+{
+    // we only support listing children and getting data
+    return OpListChildren | OpGet;
+}
+
+void Nntp::hostFound()
+{
+    if ( url() )
+        emit connectionStateChanged( ConHostFound, tr( "Host %1 found" ).arg( url()->host() ) );
+    else
+        emit connectionStateChanged( ConHostFound, tr( "Host found" ) );
+}
+
+void Nntp::connected()
+{
+    if ( url() )
+        emit connectionStateChanged( ConConnected, tr( "Connected to host %1" ).arg( url()->host() ) );
+    else
+        emit connectionStateChanged( ConConnected, tr( "Connected to host" ) );
+}
+
+void Nntp::closed()
+{
+    if ( url() )
+        emit connectionStateChanged( ConClosed, tr( "Connection to %1 closed" ).arg( url()->host() ) );
+    else
+        emit connectionStateChanged( ConClosed, tr( "Connection closed" ) );
+}
+
+void Nntp::readyRead()
+{
+    // new data arrived on the command socket
+
+    // of we should read the list of available groups, let's do so
+    if ( readGroups ) {
+        parseGroups();
+        return;
+    }
+
+    // of we should read an article, let's do so
+    if ( readArticle ) {
+        parseArticle();
+        return;
+    }
+
+    // read the new data from the socket
+    QCString s;
+    s.resize( commandSocket->bytesAvailable() + 1 );
+    commandSocket->readBlock( s.data(), commandSocket->bytesAvailable() );
+
+    if ( !url() )
+        return;
+
+    // of the code of the server response was 200, we know that the
+    // server is ready to get commands from us now
+    if ( s.left( 3 ) == "200" )
+        connectionReady = TRUE;
+}
+
+void Nntp::parseGroups()
+{
+    if ( !commandSocket->canReadLine() )
+        return;
+
+    // read one line after the other
+    while ( commandSocket->canReadLine() ) {
+        QString s = commandSocket->readLine();
+
+        // if the  line starts with a dot, all groups or articles have been listed,
+        // so we finished processing the listChildren() command
+        if ( s[ 0 ] == '.' ) {
+            readGroups = FALSE;
+            operationInProgress()->setState( StDone );
+            emit finished( operationInProgress() );
+            return;
+        }
+
+        // if the code of the server response is 215 or 211
+        // the next line will be the first group or article (depending on what we read).
+        // So let others know that we start reading now...
+        if ( s.left( 3 ) == "215" || s.left( 3 ) == "211" ) {
+            operationInProgress()->setState( StInProgress );
+            emit start( operationInProgress() );
+            continue;
+        }
+
+        // parse the line and create a QUrlInfo object
+        // which describes the child (group or article)
+        bool tab = s.find( '\t' ) != -1;
+        QString group = s.mid( 0, s.find( tab ? '\t' : ' ' ) );
+        QUrlInfo inf;
+        inf.setName( group );
+        QString path = url()->path();
+        inf.setDir( path.isEmpty() || path == "/" );
+        inf.setSymLink( FALSE );
+        inf.setFile( !inf.isDir() );
+        inf.setWritable( FALSE );
+        inf.setReadable( TRUE );
+
+        // let others know about our new child
+        emit newChild( inf, operationInProgress() );
+    }
+
+}
+
+void Nntp::parseArticle()
+{
+    if ( !commandSocket->canReadLine() )
+        return;
+
+    // read an article one line after the other
+    while ( commandSocket->canReadLine() ) {
+        QString s = commandSocket->readLine();
+
+        // if the  line starts with a dot, we finished reading something
+        if ( s[ 0 ] == '.' ) {
+            readArticle = FALSE;
+            operationInProgress()->setState( StDone );
+            emit finished( operationInProgress() );
+            return;
+        }
+
+        if ( s.right( 1 ) == "\n" )
+            s.remove( s.length() - 1, 1 );
+
+        // emit the new data of the article which we read
+        emit data( QCString( s.ascii() ), operationInProgress() );
+    }
+}
+
+void Nntp::error( int code )
+{
+    if ( code == QSocket::ErrHostNotFound ||
+         code == QSocket::ErrConnectionRefused ) {
+        // this signal is called if connecting to the server failed
+        if ( operationInProgress() ) {
+            QString msg = tr( "Host not found or couldn't connect to: \n" + url()->host() );
+            operationInProgress()->setState( StFailed );
+            operationInProgress()->setProtocolDetail( msg );
+            operationInProgress()->setErrorCode( (int)ErrHostNotFound );
+            clearOperationQueue();
+            emit finished( operationInProgress() );
+        }
+    }
+}
+

+ +