Avoid an endless recursion situation

[wxWidgets.git] / src / common / sckipc.cpp

diff --git a/src/common/sckipc.cpp b/src/common/sckipc.cpp
index 55fcb3104bd01e34ecd048fd674e32200300c691..0f1173baa6d6db09af192b1ea800b38443b69a29 100644 (file)
--- a/src/common/sckipc.cpp
+++ b/src/common/sckipc.cpp
@@ -1,503 +1,932 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        sckipc.cpp
+// Name:        src/common/sckipc.cpp

 // Purpose:     Interprocess communication implementation (wxSocket version)
 // Purpose:     Interprocess communication implementation (wxSocket version)

-// Author:      Julian Smart, Guilhem Lavaux
+// Author:      Julian Smart

 // Modified by: Guilhem Lavaux (big rewrite) May 1997, 1998
 // Modified by: Guilhem Lavaux (big rewrite) May 1997, 1998

+//              Guillermo Rodriguez (updated for wxSocket v2) Jan 2000
+//                                  (callbacks deprecated)    Mar 2000
+//              Vadim Zeitlin (added support for Unix sockets) Apr 2002
+//                            (use buffering, many fixes/cleanup) Oct 2008

 // Created:     1993
 // RCS-ID:      $Id$
 // Created:     1993
 // RCS-ID:      $Id$

-// Copyright:   (c) Julian Smart 1993, Guilhem Lavaux 1997, 1998
-// Licence:     wxWindows license
+// Copyright:   (c) Julian Smart 1993
+//              (c) Guilhem Lavaux 1997, 1998
+//              (c) 2000 Guillermo Rodriguez <guille@iies.es>
+// Licence:     wxWindows licence

 /////////////////////////////////////////////////////////////////////////////
 
 /////////////////////////////////////////////////////////////////////////////
 

-#ifdef __GNUG__
-#pragma implementation "sckipc.h"
+// ==========================================================================
+// declarations
+// ==========================================================================
+
+// --------------------------------------------------------------------------
+// headers
+// --------------------------------------------------------------------------
+
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+    #pragma hdrstop
+#endif
+
+#if wxUSE_SOCKETS && wxUSE_IPC && wxUSE_STREAMS
+
+#include "wx/sckipc.h"
+
+#ifndef WX_PRECOMP
+    #include "wx/log.h"
+    #include "wx/event.h"
+    #include "wx/module.h"

 #endif
 
 #include <stdlib.h>
 #include <stdio.h>
 #endif
 
 #include <stdlib.h>
 #include <stdio.h>

+#include <errno.h>
+
+#include "wx/socket.h"
+
+// --------------------------------------------------------------------------
+// macros and constants
+// --------------------------------------------------------------------------
+
+namespace
+{
+
+// Message codes (don't change them to avoid breaking the existing code using
+// wxIPC protocol!)
+enum IPCCode
+{
+    IPC_EXECUTE         = 1,
+    IPC_REQUEST         = 2,
+    IPC_POKE            = 3,
+    IPC_ADVISE_START    = 4,
+    IPC_ADVISE_REQUEST  = 5,
+    IPC_ADVISE          = 6,
+    IPC_ADVISE_STOP     = 7,
+    IPC_REQUEST_REPLY   = 8,
+    IPC_FAIL            = 9,
+    IPC_CONNECT         = 10,
+    IPC_DISCONNECT      = 11,
+    IPC_MAX
+};
+
+} // anonymous namespace
+
+// headers needed for umask()
+#ifdef __UNIX_LIKE__
+    #include <sys/types.h>
+    #include <sys/stat.h>
+#endif // __UNIX_LIKE__
+
+// ----------------------------------------------------------------------------
+// private functions
+// ----------------------------------------------------------------------------
+
+// get the address object for the given server name, the caller must delete it
+static wxSockAddress *
+GetAddressFromName(const wxString& serverName,
+                   const wxString& host = wxEmptyString)
+{
+    // we always use INET sockets under non-Unix systems
+#if defined(__UNIX__) && !defined(__WINDOWS__) && !defined(__WINE__)
+    // under Unix, if the server name looks like a path, create a AF_UNIX
+    // socket instead of AF_INET one
+    if ( serverName.Find(wxT('/')) != wxNOT_FOUND )
+    {
+        wxUNIXaddress *addr = new wxUNIXaddress;
+        addr->Filename(serverName);
+
+        return addr;
+    }
+#endif // Unix/!Unix
+    {
+        wxIPV4address *addr = new wxIPV4address;
+        addr->Service(serverName);
+        if ( !host.empty() )
+        {
+            addr->Hostname(host);
+        }
+
+        return addr;
+    }
+}
+
+// --------------------------------------------------------------------------
+// wxTCPEventHandler stuff (private class)
+// --------------------------------------------------------------------------
+
+class wxTCPEventHandler : public wxEvtHandler
+{
+public:
+    wxTCPEventHandler() : wxEvtHandler() { }
+
+    void Client_OnRequest(wxSocketEvent& event);
+    void Server_OnRequest(wxSocketEvent& event);
+
+private:
+    void HandleDisconnect(wxTCPConnection *connection);
+
+    DECLARE_EVENT_TABLE()
+    wxDECLARE_NO_COPY_CLASS(wxTCPEventHandler);
+};
+
+enum
+{
+    _CLIENT_ONREQUEST_ID = 1000,
+    _SERVER_ONREQUEST_ID
+};
+
+// --------------------------------------------------------------------------
+// wxTCPEventHandlerModule (private class)
+// --------------------------------------------------------------------------
+
+class wxTCPEventHandlerModule : public wxModule
+{
+public:
+    wxTCPEventHandlerModule() : wxModule() { }
+
+    // get the global wxTCPEventHandler creating it if necessary
+    static wxTCPEventHandler& GetHandler()
+    {
+        if ( !ms_handler )
+            ms_handler = new wxTCPEventHandler;
+
+        return *ms_handler;
+    }
+
+    // as ms_handler is initialized on demand, don't do anything in OnInit()
+    virtual bool OnInit() { return true; }
+    virtual void OnExit() { wxDELETE(ms_handler); }
+
+private:
+    static wxTCPEventHandler *ms_handler;

 
 

-#ifdef WXPREC
-#include <wx/wxprec.h>
+    DECLARE_DYNAMIC_CLASS(wxTCPEventHandlerModule)
+    wxDECLARE_NO_COPY_CLASS(wxTCPEventHandlerModule);
+};
+
+IMPLEMENT_DYNAMIC_CLASS(wxTCPEventHandlerModule, wxModule)
+
+wxTCPEventHandler *wxTCPEventHandlerModule::ms_handler = NULL;
+
+// --------------------------------------------------------------------------
+// wxIPCSocketStreams
+// --------------------------------------------------------------------------
+
+#define USE_BUFFER
+
+// this class contains the various (related) streams used by wxTCPConnection
+// and also provides a way to read from the socket stream directly
+//
+// for writing to the stream use the IPCOutput class below
+class wxIPCSocketStreams
+{
+public:
+    // ctor initializes all the streams on top of the given socket
+    //
+    // note that we use a bigger than default buffer size which matches the
+    // typical Ethernet MTU (minus TCP header overhead)
+    wxIPCSocketStreams(wxSocketBase& sock)
+        : m_socketStream(sock),
+#ifdef USE_BUFFER
+          m_bufferedOut(m_socketStream, 1448),

 #else
 #else

-#include <wx/wx.h>
+          m_bufferedOut(m_socketStream),

 #endif
 #endif

+          m_dataIn(m_socketStream),
+          m_dataOut(m_bufferedOut)
+    {
+    }

 
 

-#include "wx/socket.h"
-#include "wx/sckipc.h"
+    // expose the IO methods needed by IPC code (notice that writing is only
+    // done via IPCOutput)

 
 

-#ifdef __BORLANDC__
-#pragma hdrstop
+    // flush output
+    void Flush()
+    {
+#ifdef USE_BUFFER
+        m_bufferedOut.Sync();

 #endif
 #endif

+    }

 
 

-#if !USE_SHARED_LIBRARY
-IMPLEMENT_DYNAMIC_CLASS(wxTCPServer, wxServerBase)
-IMPLEMENT_DYNAMIC_CLASS(wxTCPClient, wxClientBase)
-IMPLEMENT_DYNAMIC_CLASS(wxTCPConnection, wxConnectionBase)
-#endif
+    // simple wrappers around the functions with the same name in
+    // wxDataInputStream
+    wxUint8 Read8()
+    {
+        Flush();
+        return m_dataIn.Read8();
+    }

 
 

-// It seems to be already defined somewhere in the Xt includes.
-#ifndef __XT__
-// Message codes
-enum {
-  IPC_EXECUTE = 1,
-  IPC_REQUEST,
-  IPC_POKE,
-  IPC_ADVISE_START,
-  IPC_ADVISE_REQUEST,
-  IPC_ADVISE,
-  IPC_ADVISE_STOP,
-  IPC_REQUEST_REPLY,
-  IPC_FAIL,
-  IPC_CONNECT,
-  IPC_DISCONNECT
-};
+    wxUint32 Read32()
+    {
+        Flush();
+        return m_dataIn.Read32();
+    }
+
+    wxString ReadString()
+    {
+        Flush();
+        return m_dataIn.ReadString();
+    }
+
+    // read arbitrary (size-prepended) data
+    //
+    // connection parameter is needed to call its GetBufferAtLeast() method
+    void *ReadData(wxConnectionBase *conn, size_t *size)
+    {
+        Flush();
+
+        wxCHECK_MSG( conn, NULL, "NULL connection parameter" );
+        wxCHECK_MSG( size, NULL, "NULL size parameter" );
+
+        *size = Read32();
+
+        void * const data = conn->GetBufferAtLeast(*size);
+        wxCHECK_MSG( data, NULL, "IPC buffer allocation failed" );
+
+        m_socketStream.Read(data, *size);
+
+        return data;
+    }
+
+    // same as above but for data preceded by the format
+    void *
+    ReadFormatData(wxConnectionBase *conn, wxIPCFormat *format, size_t *size)
+    {
+        wxCHECK_MSG( format, NULL, "NULL format parameter" );
+
+        *format = static_cast<wxIPCFormat>(Read8());
+
+        return ReadData(conn, size);
+    }
+
+
+    // these methods are only used by IPCOutput and not directly
+    wxDataOutputStream& GetDataOut() { return m_dataOut; }
+    wxOutputStream& GetUnformattedOut() { return m_bufferedOut; }
+
+private:
+    // this is the low-level underlying stream using the connection socket
+    wxSocketStream m_socketStream;
+
+    // the buffered stream is used to avoid writing all pieces of an IPC
+    // request to the socket one by one but to instead do it all at once when
+    // we're done with it
+#ifdef USE_BUFFER
+    wxBufferedOutputStream m_bufferedOut;
+#else
+    wxOutputStream& m_bufferedOut;

 #endif
 
 #endif
 

-void Server_OnRequest(wxSocketServer& server,
-                     wxSocketBase::wxRequestEvent evt,
-                     char *cdata);
-void Client_OnRequest(wxSocketBase& sock,
-                     wxSocketBase::wxRequestEvent evt,
-                     char *cdata);
+    // finally the data streams are used to be able to write typed data into
+    // the above streams easily
+    wxDataInputStream  m_dataIn;
+    wxDataOutputStream m_dataOut;

 
 

-// ---------------------------------------------------------------------------
-// wxTCPClient
-// ---------------------------------------------------------------------------
+    wxDECLARE_NO_COPY_CLASS(wxIPCSocketStreams);
+};

 
 

-wxTCPClient::wxTCPClient (void)
-  : wxClientBase()
+namespace

 {
 {

-}

 
 

-wxTCPClient::~wxTCPClient (void)
+// an object of this class should be instantiated on the stack to write to the
+// underlying socket stream
+//
+// this class is intentionally separated from wxIPCSocketStreams to ensure that
+// Flush() is always called
+class IPCOutput
+{
+public:
+    // construct an object associated with the given streams (which must have
+    // life time greater than ours as we keep a reference to it)
+    IPCOutput(wxIPCSocketStreams *streams)
+        : m_streams(*streams)
+    {
+        wxASSERT_MSG( streams, "NULL streams pointer" );
+    }
+
+    // dtor calls Flush() really sending the IPC data to the network
+    ~IPCOutput() { m_streams.Flush(); }
+
+
+    // write a byte
+    void Write8(wxUint8 i)
+    {
+        m_streams.GetDataOut().Write8(i);
+    }
+
+    // write the reply code and a string
+    void Write(IPCCode code, const wxString& str)
+    {
+        Write8(code);
+        m_streams.GetDataOut().WriteString(str);
+    }
+
+    // write the reply code, a string and a format in this order
+    void Write(IPCCode code, const wxString& str, wxIPCFormat format)
+    {
+        Write(code, str);
+        Write8(format);
+    }
+
+    // write arbitrary data
+    void WriteData(const void *data, size_t size)
+    {
+        m_streams.GetDataOut().Write32(size);
+        m_streams.GetUnformattedOut().Write(data, size);
+    }
+
+
+private:
+    wxIPCSocketStreams& m_streams;
+
+    wxDECLARE_NO_COPY_CLASS(IPCOutput);
+};
+
+} // anonymous namespace
+
+// ==========================================================================
+// implementation
+// ==========================================================================
+
+IMPLEMENT_DYNAMIC_CLASS(wxTCPServer, wxServerBase)
+IMPLEMENT_DYNAMIC_CLASS(wxTCPClient, wxClientBase)
+IMPLEMENT_CLASS(wxTCPConnection, wxConnectionBase)
+
+// --------------------------------------------------------------------------
+// wxTCPClient
+// --------------------------------------------------------------------------
+
+wxTCPClient::wxTCPClient()
+           : wxClientBase()

 {
 }
 
 bool wxTCPClient::ValidHost(const wxString& host)
 {
 {
 }
 
 bool wxTCPClient::ValidHost(const wxString& host)
 {

-  wxIPV4address addr;
+    wxIPV4address addr;

 
 

-  return addr.Hostname(host);
+    return addr.Hostname(host);

 }
 
 }
 

-wxConnectionBase *wxTCPClient::MakeConnection (const wxString& host,
-                                               const wxString& server_name,
-                                               const wxString& topic)
+wxConnectionBase *wxTCPClient::MakeConnection(const wxString& host,
+                                              const wxString& serverName,
+                                              const wxString& topic)

 {
 {

-  wxIPV4address addr;
-  wxSocketHandler *hsock = &wxSocketHandler::Master();
-  wxSocketClient *client = hsock->CreateClient();
-  wxSocketStream *stream = new wxSocketStream(*client);
-  wxDataStream data_s(*stream);
-  
-  client->SetNotify(wxSocketBase::REQ_READ | wxSocketBase::REQ_LOST);
-  addr.Service(server_name);
-  addr.Hostname(host);
-
-  if (!client->Connect(addr)) {
-    delete client;
-    return NULL;
-  }
-  client->Notify(FALSE);
-
-  // Send topic name, and enquire whether this has succeeded
-  unsigned char msg;
-  
-  data_s.Write8(IPC_CONNECT);
-  data_s.WriteString(topic);
-  
-  msg = data_s.Read8();
-  
-  // OK! Confirmation.
-  if (msg == IPC_CONNECT) {
-    wxTCPConnection *connection = (wxTCPConnection *)OnMakeConnection ();
-    if (connection) {
-      if (!connection->IsKindOf(CLASSINFO(wxTCPConnection))) {
-        delete connection;
+    wxSockAddress *addr = GetAddressFromName(serverName, host);
+    if ( !addr )

         return NULL;
         return NULL;

-      }
-      connection->m_topic = topic;
-      client->Callback(Client_OnRequest);
-      client->CallbackData((char *)connection);
-      client->Notify(TRUE);
-      return connection;
-    } else {
-      delete client;
-      return NULL;
+
+    wxSocketClient * const client = new wxSocketClient(wxSOCKET_WAITALL);
+    wxIPCSocketStreams * const streams = new wxIPCSocketStreams(*client);
+
+    bool ok = client->Connect(*addr);
+    delete addr;
+
+    if ( ok )
+    {
+        // Send topic name, and enquire whether this has succeeded
+        IPCOutput(streams).Write(IPC_CONNECT, topic);
+
+        unsigned char msg = streams->Read8();
+
+        // OK! Confirmation.
+        if (msg == IPC_CONNECT)
+        {
+            wxTCPConnection *
+                connection = (wxTCPConnection *)OnMakeConnection ();
+
+            if (connection)
+            {
+                if (connection->IsKindOf(CLASSINFO(wxTCPConnection)))
+                {
+                    connection->m_topic = topic;
+                    connection->m_sock  = client;
+                    connection->m_streams = streams;
+                    client->SetEventHandler(wxTCPEventHandlerModule::GetHandler(),
+                                            _CLIENT_ONREQUEST_ID);
+                    client->SetClientData(connection);
+                    client->SetNotify(wxSOCKET_INPUT_FLAG | wxSOCKET_LOST_FLAG);
+                    client->Notify(true);
+                    return connection;
+                }
+                else
+                {
+                    delete connection;
+                    // and fall through to delete everything else
+                }
+            }
+        }

     }
     }

-  } else {
-    delete client;
+
+    // Something went wrong, delete everything
+    delete streams;
+    client->Destroy();
+

     return NULL;
     return NULL;

-  }
-  return NULL;

 }
 
 wxConnectionBase *wxTCPClient::OnMakeConnection()
 {
 }
 
 wxConnectionBase *wxTCPClient::OnMakeConnection()
 {

-  return new wxTCPConnection;
+    return new wxTCPConnection();

 }
 
 }
 

-// ---------------------------------------------------------------------------
+// --------------------------------------------------------------------------

 // wxTCPServer
 // wxTCPServer

-// ---------------------------------------------------------------------------
+// --------------------------------------------------------------------------

 
 

-wxTCPServer::wxTCPServer (void)
-  : wxServerBase()
+wxTCPServer::wxTCPServer()
+           : wxServerBase()

 {
 {

+    m_server = NULL;

 }
 
 }
 

-bool wxTCPServer::Create(const wxString& server_name)
+bool wxTCPServer::Create(const wxString& serverName)

 {
 {

-  wxIPV4address addr;
-  wxSocketHandler *hsock = &wxSocketHandler::Master();
-  wxSocketServer *server;
+    // Destroy previous server, if any
+    if (m_server)
+    {
+        m_server->SetClientData(NULL);
+        m_server->Destroy();
+        m_server = NULL;
+    }

 
 

-  addr.Service(server_name);
+    wxSockAddress *addr = GetAddressFromName(serverName);
+    if ( !addr )
+        return false;
+
+#ifdef __UNIX_LIKE__
+    mode_t umaskOld;
+    if ( addr->Type() == wxSockAddress::UNIX )
+    {
+        // ensure that the file doesn't exist as otherwise calling socket()
+        // would fail
+        int rc = remove(serverName.fn_str());
+        if ( rc < 0 && errno != ENOENT )
+        {
+            delete addr;
+
+            return false;
+        }
+
+        // also set the umask to prevent the others from reading our file
+        umaskOld = umask(077);
+    }
+    else
+    {
+        // unused anyhow but shut down the compiler warnings
+        umaskOld = 0;
+    }
+#endif // __UNIX_LIKE__

 
 

-  // Create a socket listening on specified port
-  server = hsock->CreateServer(addr);
-  server->Callback((wxSocketBase::wxSockCbk)Server_OnRequest);
-  server->SetNotify(wxSocketBase::REQ_ACCEPT);
+    // Create a socket listening on the specified port (reusing it to allow
+    // restarting the server listening on the same port as was used by the
+    // previous instance of this server)
+    m_server = new wxSocketServer(*addr, wxSOCKET_WAITALL | wxSOCKET_REUSEADDR);

 
 

-  server->CallbackData((char *)this);
+#ifdef __UNIX_LIKE__
+    if ( addr->Type() == wxSockAddress::UNIX )
+    {
+        // restore the umask
+        umask(umaskOld);

 
 

-  return TRUE;
+        // save the file name to remove it later
+        m_filename = serverName;
+    }
+#endif // __UNIX_LIKE__
+
+    delete addr;
+
+    if (!m_server->Ok())
+    {
+        m_server->Destroy();
+        m_server = NULL;
+
+        return false;
+    }
+
+    m_server->SetEventHandler(wxTCPEventHandlerModule::GetHandler(),
+                              _SERVER_ONREQUEST_ID);
+    m_server->SetClientData(this);
+    m_server->SetNotify(wxSOCKET_CONNECTION_FLAG);
+    m_server->Notify(true);
+
+    return true;

 }
 
 }
 

-wxTCPServer::~wxTCPServer (void)
+wxTCPServer::~wxTCPServer()

 {
 {

+    if ( m_server )
+    {
+        m_server->SetClientData(NULL);
+        m_server->Destroy();
+    }
+
+#ifdef __UNIX_LIKE__
+    if ( !m_filename.empty() )
+    {
+        if ( remove(m_filename.fn_str()) != 0 )
+        {
+            wxLogDebug(wxT("Stale AF_UNIX file '%s' left."), m_filename.c_str());
+        }
+    }
+#endif // __UNIX_LIKE__

 }
 
 }
 

-wxConnectionBase *wxTCPServer::OnAcceptConnection(const wxString& topic)
+wxConnectionBase *
+wxTCPServer::OnAcceptConnection(const wxString& WXUNUSED(topic))

 {
 {

-  return new wxTCPConnection();
+    return new wxTCPConnection();

 }
 
 }
 

-// ---------------------------------------------------------------------------
+// --------------------------------------------------------------------------

 // wxTCPConnection
 // wxTCPConnection

-// ---------------------------------------------------------------------------
+// --------------------------------------------------------------------------

 
 

-wxTCPConnection::wxTCPConnection (void)
-  : wxConnectionBase(),
-    m_sock(NULL), m_sockstrm(NULL), m_codec(NULL)
+void wxTCPConnection::Init()

 {
 {

+    m_sock = NULL;
+    m_streams = NULL;

 }
 
 }
 

-wxTCPConnection::~wxTCPConnection (void)
+wxTCPConnection::~wxTCPConnection()

 {
 {

-  wxDELETE(m_sock);
-  wxDELETE(m_codec);
-  wxDELETE(m_sockstrm);
+    Disconnect();
+
+    if ( m_sock )
+    {
+        m_sock->SetClientData(NULL);
+        m_sock->Destroy();
+    }
+
+    delete m_streams;

 }
 
 }
 

-void wxTCPConnection::Compress(bool on)
+void wxTCPConnection::Compress(bool WXUNUSED(on))

 {
 {

-  // Use wxLZWStream
+    // TODO

 }
 
 // Calls that CLIENT can make.
 }
 
 // Calls that CLIENT can make.

-bool wxTCPConnection::Disconnect (void)
+bool wxTCPConnection::Disconnect()

 {
 {

-  // Send the the disconnect message to the peer.
-  m_codec->Write8(IPC_DISCONNECT);
-  m_sock->Close();
+    if ( !GetConnected() )
+        return true;

 
 

-  return TRUE;
+    // Send the disconnect message to the peer.
+    IPCOutput(m_streams).Write8(IPC_DISCONNECT);
+
+    if ( m_sock )
+    {
+        m_sock->Notify(false);
+        m_sock->Close();
+    }
+
+    SetConnected(false);
+
+    return true;

 }
 
 }
 

-bool wxTCPConnection::Execute (char *data, int size, wxDataFormat format)
+bool wxTCPConnection::DoExecute(const void *data,
+                                size_t size,
+                                wxIPCFormat format)

 {
 {

-  if (!m_sock->IsConnected())
-    return FALSE;
-
-  // Prepare EXECUTE message
-  m_codec->Write8(IPC_EXECUTE);
-  m_codec->Write8(format);
-  if (size < 0)
-    m_codec->WriteString(data);
-  else {
-    m_codec->Write32(size);
-    m_codec->Write(data, size);
-  }
-
-  return TRUE;
+    if ( !m_sock->IsConnected() )
+        return false;
+
+    // Prepare EXECUTE message
+    IPCOutput out(m_streams);
+    out.Write8(IPC_EXECUTE);
+    out.Write8(format);
+
+    out.WriteData(data, size);
+
+    return true;

 }
 
 }
 

-char *wxTCPConnection::Request (const wxString& item, int *size, wxDataFormat format)
+const void *wxTCPConnection::Request(const wxString& item,
+                                     size_t *size,
+                                     wxIPCFormat format)

 {
 {

-  if (!m_sock->IsConnected())
-    return NULL;
+    if ( !m_sock->IsConnected() )
+        return NULL;

 
 

-  m_codec->Write8(IPC_REQUEST);
-  m_codec->WriteString(item);
-  m_codec->Write8(format);
+    IPCOutput(m_streams).Write(IPC_REQUEST, item, format);

 
 

-  // If Unpack doesn't initialize it.
-  int ret;
+    const int ret = m_streams->Read8();
+    if ( ret != IPC_REQUEST_REPLY )
+        return NULL;

 
 

-  ret = m_codec->Read8();
-  if (ret == IPC_FAIL)
-    return NULL;
-  else {
-    size_t s;
-    char *data = NULL;
-
-    s = m_codec->Read32();
-    data = new char[s];
-    m_codec->Read(data, s);
-
-    if (size)
-      *size = s;
-    return data;
-  }
+    // ReadData() needs a non-NULL size pointer but the client code can call us
+    // with NULL pointer (this makes sense if it knows that it always works
+    // with NUL-terminated strings)
+    size_t sizeFallback;
+    return m_streams->ReadData(this, size ? size : &sizeFallback);

 }
 
 }
 

-bool wxTCPConnection::Poke (const wxString& item, char *data, int size, wxDataFormat format)
+bool wxTCPConnection::DoPoke(const wxString& item,
+                             const void *data,
+                             size_t size,
+                             wxIPCFormat format)

 {
 {

-  if (!m_sock->IsConnected())
-    return FALSE;
-
-  m_codec->Write8(IPC_POKE);
-  m_codec->WriteString(item);
-  m_codec->Write8(format);
-  if (size < 0)
-    m_codec->WriteString(data);
-  else {
-    m_codec->Write32(size);
-    m_codec->Write(data, size);
-  }
-
-  return TRUE;
+    if ( !m_sock->IsConnected() )
+        return false;
+
+    IPCOutput out(m_streams);
+    out.Write(IPC_POKE, item, format);
+    out.WriteData(data, size);
+
+    return true;

 }
 
 }
 

-bool wxTCPConnection::StartAdvise (const wxString& item)
+bool wxTCPConnection::StartAdvise(const wxString& item)

 {
 {

-  int ret;
+    if ( !m_sock->IsConnected() )
+        return false;

 
 

-  if (!m_sock->IsConnected())
-    return FALSE;
+    IPCOutput(m_streams).Write(IPC_ADVISE_START, item);

 
 

-  m_codec->Write8(IPC_ADVISE_START);
-  m_codec->WriteString(item);
+    const int ret = m_streams->Read8();

 
 

-  ret = m_codec->Read8();
-
-  if (ret != IPC_FAIL)
-    return TRUE;
-  else
-    return FALSE;
+    return ret == IPC_ADVISE_START;

 }
 
 bool wxTCPConnection::StopAdvise (const wxString& item)
 {
 }
 
 bool wxTCPConnection::StopAdvise (const wxString& item)
 {

-  int msg;
-
-  if (!m_sock->IsConnected())
-    return FALSE;
+    if ( !m_sock->IsConnected() )
+        return false;

 
 

-  m_codec->Write8(IPC_ADVISE_STOP);
-  m_codec->WriteString(item);
+    IPCOutput(m_streams).Write(IPC_ADVISE_STOP, item);

 
 

-  msg = m_codec->Read8();
+    const int ret = m_streams->Read8();

 
 

-  if (msg != IPC_FAIL)
-    return TRUE;
-  else
-    return FALSE;
+    return ret == IPC_ADVISE_STOP;

 }
 
 // Calls that SERVER can make
 }
 
 // Calls that SERVER can make

-bool wxTCPConnection::Advise (const wxString& item,
-                              char *data, int size, wxDataFormat format)
+bool wxTCPConnection::DoAdvise(const wxString& item,
+                               const void *data,
+                               size_t size,
+                               wxIPCFormat format)

 {
 {

-  if (!m_sock->IsConnected())
-    return FALSE;
-
-  m_codec->Write8(IPC_ADVISE);
-  m_codec->WriteString(item);
-  m_codec->Write8(format);
-  if (size < 0)
-    m_codec->WriteString(data);
-  else {
-    m_codec->Write32(size);
-    m_codec->Write(data, size);
-  }
-
-  return TRUE;
+    if ( !m_sock->IsConnected() )
+        return false;
+
+    IPCOutput out(m_streams);
+    out.Write(IPC_ADVISE, item, format);
+    out.WriteData(data, size);
+
+    return true;

 }
 
 }
 

-void Client_OnRequest(wxSocketBase& sock, wxSocketBase::wxRequestEvent evt,
-                     char *cdata)
+// --------------------------------------------------------------------------
+// wxTCPEventHandler (private class)
+// --------------------------------------------------------------------------
+
+BEGIN_EVENT_TABLE(wxTCPEventHandler, wxEvtHandler)
+    EVT_SOCKET(_CLIENT_ONREQUEST_ID, wxTCPEventHandler::Client_OnRequest)
+    EVT_SOCKET(_SERVER_ONREQUEST_ID, wxTCPEventHandler::Server_OnRequest)
+END_EVENT_TABLE()
+
+void wxTCPEventHandler::HandleDisconnect(wxTCPConnection *connection)

 {
 {

-  int msg = 0;
-  wxTCPConnection *connection = (wxTCPConnection *)cdata;
-  wxDataStream *codec;
-  wxString topic_name = connection->m_topic;
-  wxString item;
-
-  // The socket handler signals us that we lost the connection: destroy all.
-  if (evt == wxSocketBase::EVT_LOST) {
-    sock.Close();
-    connection->OnDisconnect();
-    return;
-  }
-
-  // Receive message number.
-  codec = connection->m_codec;
-  msg = codec->Read8();
-
-  switch (msg) {
-  case IPC_EXECUTE: {
-    char *data;
-    size_t size; 
-    wxDataFormat format;
-    
-    format = (wxDataFormat)codec->Read8();
-    size = codec->Read32();
-    data = new char[size];
-    codec->Read(data, size);
-
-    connection->OnExecute (topic_name, data, size, format);
-
-    delete [] data;
-    break;
-  }
-  case IPC_ADVISE: {
-    char *data;
-    size_t size;
-    wxDataFormat format;
-
-    item = codec->ReadString();
-    format = (wxDataFormat)codec->Read8();
-    size = codec->Read32();
-    data = new char[size];
-    codec->Read(data, size);
-    
-    connection->OnAdvise (topic_name, item, data, size, format);
-
-    delete [] data;
-    break;
-  }
-  case IPC_ADVISE_START: {
-    item = codec->ReadString();
-
-    bool ok = connection->OnStartAdvise (topic_name, item);
-    if (ok)
-      codec->Write8(IPC_ADVISE_START);
-    else
-      codec->Write8(IPC_FAIL);
+    // connection was closed (either gracefully or not): destroy everything
+    connection->m_sock->Notify(false);
+    connection->m_sock->Close();

 
 

-    break;
-  }
-  case IPC_ADVISE_STOP: {
-    item = codec->ReadString();
+    // don't leave references to this soon-to-be-dangling connection in the
+    // socket as it won't be destroyed immediately as its destruction will be
+    // delayed in case there are more events pending for it
+    connection->m_sock->SetClientData(NULL);

 
 

-    bool ok = connection->OnStopAdvise (topic_name, item);
-    if (ok)
-      codec->Write8(IPC_ADVISE_STOP);
-    else
-      codec->Write8(IPC_FAIL);
-
-    break;
-  }
-  case IPC_POKE: {
-    wxDataFormat format;
-    size_t size;
-    char *data;
-
-    item = codec->ReadString();
-    format = (wxDataFormat)codec->Read8();
-    size = codec->Read32();
-    data = new char[size];
-    codec->Read(data, size);
-    
-    connection->OnPoke (topic_name, item, data, size, format);
-
-    delete [] data;
-
-    break;
-  }
-  case IPC_REQUEST: {
-    wxDataFormat format;
-
-    item = codec->ReadString();
-    format = (wxDataFormat)codec->Read8();
-
-    int user_size = -1;
-    char *user_data = connection->OnRequest (topic_name, item, &user_size, format);
-
-    if (user_data) {
-      codec->Write8(IPC_REQUEST_REPLY);
-      if (user_size != -1) {
-        codec->Write32(user_size);
-        codec->Write(user_data, user_size);
-      } else
-        codec->WriteString(user_data);
-    } else
-      codec->Write8(IPC_FAIL);
-
-    break;
-  }
-  case IPC_DISCONNECT: {
-    sock.Close();
+    connection->SetConnected(false);

     connection->OnDisconnect();
     connection->OnDisconnect();

-    break;
-  }
-  default:
-    codec->Write8(IPC_FAIL);
-    break;
-  }

 }
 
 }
 

-void Server_OnRequest(wxSocketServer& server,
-                     wxSocketBase::wxRequestEvent evt, char *cdata)
+void wxTCPEventHandler::Client_OnRequest(wxSocketEvent &event)
+{
+    wxSocketBase *sock = event.GetSocket();
+    if (!sock)
+        return;
+
+    wxSocketNotify evt = event.GetSocketEvent();
+    wxTCPConnection * const
+        connection = static_cast<wxTCPConnection *>(sock->GetClientData());
+
+    // This socket is being deleted; skip this event
+    if (!connection)
+        return;
+
+    if ( evt == wxSOCKET_LOST )
+    {
+        HandleDisconnect(connection);
+        return;
+    }
+
+    // Receive message number.
+    wxIPCSocketStreams * const streams = connection->m_streams;
+
+    const wxString topic = connection->m_topic;
+    wxString item;
+
+    bool error = false;
+
+    const int msg = streams->Read8();
+    switch ( msg )
+    {
+        case IPC_EXECUTE:
+            {
+                wxIPCFormat format;
+                size_t size wxDUMMY_INITIALIZE(0);
+                void * const
+                    data = streams->ReadFormatData(connection, &format, &size);
+                if ( data )
+                    connection->OnExecute(topic, data, size, format);
+                else
+                    error = true;
+            }
+            break;
+
+        case IPC_ADVISE:
+            {
+                item = streams->ReadString();
+
+                wxIPCFormat format;
+                size_t size wxDUMMY_INITIALIZE(0);
+                void * const
+                    data = streams->ReadFormatData(connection, &format, &size);
+
+                if ( data )
+                    connection->OnAdvise(topic, item, data, size, format);
+                else
+                    error = true;
+            }
+            break;
+
+        case IPC_ADVISE_START:
+            {
+                item = streams->ReadString();
+
+                IPCOutput(streams).Write8(connection->OnStartAdvise(topic, item)
+                                            ? IPC_ADVISE_START
+                                            : IPC_FAIL);
+            }
+            break;
+
+        case IPC_ADVISE_STOP:
+            {
+                item = streams->ReadString();
+
+                IPCOutput(streams).Write8(connection->OnStopAdvise(topic, item)
+                                             ? IPC_ADVISE_STOP
+                                             : IPC_FAIL);
+            }
+            break;
+
+        case IPC_POKE:
+            {
+                item = streams->ReadString();
+                wxIPCFormat format = (wxIPCFormat)streams->Read8();
+
+                size_t size wxDUMMY_INITIALIZE(0);
+                void * const data = streams->ReadData(connection, &size);
+
+                if ( data )
+                    connection->OnPoke(topic, item, data, size, format);
+                else
+                    error = true;
+            }
+            break;
+
+        case IPC_REQUEST:
+            {
+                item = streams->ReadString();
+
+                wxIPCFormat format = (wxIPCFormat)streams->Read8();
+
+                size_t user_size = wxNO_LEN;
+                const void *user_data = connection->OnRequest(topic,
+                                                              item,
+                                                              &user_size,
+                                                              format);
+
+                if ( !user_data )
+                {
+                    IPCOutput(streams).Write8(IPC_FAIL);
+                    break;
+                }
+
+                IPCOutput out(streams);
+                out.Write8(IPC_REQUEST_REPLY);
+
+                if ( user_size == wxNO_LEN )
+                {
+                    switch ( format )
+                    {
+                        case wxIPC_TEXT:
+                        case wxIPC_UTF8TEXT:
+                            user_size = strlen((const char *)user_data) + 1;  // includes final NUL
+                            break;
+                        case wxIPC_UNICODETEXT:
+                            user_size = (wcslen((const wchar_t *)user_data) + 1) * sizeof(wchar_t);  // includes final NUL
+                            break;
+                        default:
+                            user_size = 0;
+                    }
+                }
+
+                out.WriteData(user_data, user_size);
+            }
+            break;
+
+        case IPC_DISCONNECT:
+            HandleDisconnect(connection);
+            break;
+
+        case IPC_FAIL:
+            wxLogDebug("Unexpected IPC_FAIL received");
+            error = true;
+            break;
+
+        default:
+            wxLogDebug("Unknown message code %d received.", msg);
+            error = true;
+            break;
+    }
+
+    if ( error )
+        IPCOutput(streams).Write8(IPC_FAIL);
+}
+
+void wxTCPEventHandler::Server_OnRequest(wxSocketEvent &event)

 {
 {

-  wxTCPServer *ipcserv = (wxTCPServer *)cdata;
-  wxSocketStream *stream;
-  wxDataStream *codec;
-
-  if (evt != wxSocketBase::EVT_ACCEPT)
-    return;
-
-  /* Accept the connection, getting a new socket */
-  wxSocketBase *sock = server.Accept();
-  sock->Notify(FALSE);
-  sock->SetNotify(wxSocketBase::REQ_READ | wxSocketBase::REQ_LOST);
-
-  stream = new wxSocketStream(*sock);
-  codec = new wxDataStream(*stream);
-
-  if (!sock->Ok())
-    return;
-
-  int msg;
-  msg = codec->Read8();
-
-  if (msg == IPC_CONNECT) {
-    wxString topic_name;
-    topic_name = codec->ReadString();
-
-    /* Register new socket with the notifier */
-    wxTCPConnection *new_connection =
-         (wxTCPConnection *)ipcserv->OnAcceptConnection (topic_name);
-    if (new_connection) {
-      if (!new_connection->IsKindOf(CLASSINFO(wxTCPConnection))) {
-        delete new_connection;
-        codec->Write8(IPC_FAIL);
+    wxSocketServer *server = (wxSocketServer *) event.GetSocket();
+    if (!server)
+        return;
+    wxTCPServer *ipcserv = (wxTCPServer *) server->GetClientData();
+
+    // This socket is being deleted; skip this event
+    if (!ipcserv)
+        return;
+
+    if (event.GetSocketEvent() != wxSOCKET_CONNECTION)
+        return;
+
+    // Accept the connection, getting a new socket
+    wxSocketBase *sock = server->Accept();
+    if (!sock)
+        return;
+    if (!sock->Ok())
+    {
+        sock->Destroy();

         return;
         return;

-      }
-      // Acknowledge success
-      codec->Write8(IPC_CONNECT);
-      
-      new_connection->m_topic = topic_name;
-      new_connection->m_sockstrm = stream;
-      new_connection->m_codec = codec;
-      sock->Callback(Client_OnRequest);
-      sock->CallbackData((char *)new_connection);
-      sock->Notify(TRUE);
-    } else {
-      // Send failure message
-      codec->Write8(IPC_FAIL);

     }
     }

-  }
+
+    wxIPCSocketStreams *streams = new wxIPCSocketStreams(*sock);
+
+    {
+        IPCOutput out(streams);
+
+        const int msg = streams->Read8();
+        if ( msg == IPC_CONNECT )
+        {
+            const wxString topic = streams->ReadString();
+
+            wxTCPConnection *new_connection =
+                (wxTCPConnection *)ipcserv->OnAcceptConnection (topic);
+
+            if (new_connection)
+            {
+                if (new_connection->IsKindOf(CLASSINFO(wxTCPConnection)))
+                {
+                    // Acknowledge success
+                    out.Write8(IPC_CONNECT);
+
+                    new_connection->m_sock = sock;
+                    new_connection->m_streams = streams;
+                    new_connection->m_topic = topic;
+                    sock->SetEventHandler(wxTCPEventHandlerModule::GetHandler(),
+                                          _CLIENT_ONREQUEST_ID);
+                    sock->SetClientData(new_connection);
+                    sock->SetNotify(wxSOCKET_INPUT_FLAG | wxSOCKET_LOST_FLAG);
+                    sock->Notify(true);
+                    return;
+                }
+                else
+                {
+                    delete new_connection;
+                    // and fall through to delete everything else
+                }
+            }
+        }
+
+        // Something went wrong, send failure message and delete everything
+        out.Write8(IPC_FAIL);
+    } // IPCOutput object is destroyed here, before destroying stream
+
+    delete streams;
+    sock->Destroy();

 }
 }

+
+#endif // wxUSE_SOCKETS && wxUSE_IPC && wxUSE_STREAMS