Don't use DDEExec registry key in wxMSW wxExecute() if it's empty.

[wxWidgets.git] / src / msw / dde.cpp

diff --git a/src/msw/dde.cpp b/src/msw/dde.cpp
index 1ddd1a726d719001543bbc61ace2a540b4d8af8a..f11a8492085e8e39121d1abee56194fac6cd5df9 100644 (file)
--- a/src/msw/dde.cpp
+++ b/src/msw/dde.cpp
@@ -1,10 +1,9 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        msw/dde.cpp
+// Name:        src/msw/dde.cpp

 // Purpose:     DDE classes
 // Author:      Julian Smart
 // Modified by:
 // Created:     01/02/97
 // Purpose:     DDE classes
 // Author:      Julian Smart
 // Modified by:
 // Created:     01/02/97

-// RCS-ID:      $Id$

 // Copyright:   (c) Julian Smart
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 // Copyright:   (c) Julian Smart
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////


@@ -17,10 +16,6 @@
 // headers
 // ----------------------------------------------------------------------------
 
 // headers
 // ----------------------------------------------------------------------------
 

-#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
-    #pragma implementation "dde.h"
-#endif
-

 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 


@@ -33,40 +28,20 @@
 #ifndef WX_PRECOMP
     #include "wx/utils.h"
     #include "wx/app.h"
 #ifndef WX_PRECOMP
     #include "wx/utils.h"
     #include "wx/app.h"

+    #include "wx/hashmap.h"
+    #include "wx/module.h"

 #endif
 
 #endif
 

-#include "wx/module.h"

 #include "wx/dde.h"
 #include "wx/intl.h"
 #include "wx/dde.h"
 #include "wx/intl.h"

-#include "wx/hashmap.h"
+#include "wx/buffer.h"
+#include "wx/strconv.h"

 
 #include "wx/msw/private.h"
 
 #include <string.h>
 #include <ddeml.h>
 
 
 #include "wx/msw/private.h"
 
 #include <string.h>
 #include <ddeml.h>
 

-#ifdef __GNUWIN32_OLD__
-    #include "wx/msw/gnuwin32/extra.h"
-#endif
-
-// some compilers headers don't define this one (mingw32)
-#ifndef DMLERR_NO_ERROR
-    #define DMLERR_NO_ERROR (0)
-
-    // this one is also missing from some mingw32 headers, but there is no way
-    // to test for it (I know of) - the test for DMLERR_NO_ERROR works for me,
-    // but is surely not the right thing to do
-    extern "C"
-    HDDEDATA STDCALL DdeClientTransaction(LPBYTE pData,
-                                          DWORD cbData,
-                                          HCONV hConv,
-                                          HSZ hszItem,
-                                          UINT wFmt,
-                                          UINT wType,
-                                          DWORD dwTimeout,
-                                          LPDWORD pdwResult);
-#endif // no DMLERR_NO_ERROR
-

 // ----------------------------------------------------------------------------
 // macros and constants
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // macros and constants
 // ----------------------------------------------------------------------------


@@ -112,6 +87,7 @@ static HSZ DDEGetAtom(const wxString& string);
 // string handles
 static HSZ DDEAtomFromString(const wxString& s);
 static wxString DDEStringFromAtom(HSZ hsz);
 // string handles
 static HSZ DDEAtomFromString(const wxString& s);
 static wxString DDEStringFromAtom(HSZ hsz);

+static void DDEFreeString(HSZ hsz);

 
 // error handling
 static wxString DDEGetErrorMsg(UINT error);
 
 // error handling
 static wxString DDEGetErrorMsg(UINT error);


@@ -129,9 +105,9 @@ static wxAtomMap wxAtomTable;
 
 #include "wx/listimpl.cpp"
 
 
 #include "wx/listimpl.cpp"
 

-WX_DEFINE_LIST(wxDDEClientList);
-WX_DEFINE_LIST(wxDDEServerList);
-WX_DEFINE_LIST(wxDDEConnectionList);
+WX_DEFINE_LIST(wxDDEClientList)
+WX_DEFINE_LIST(wxDDEServerList)
+WX_DEFINE_LIST(wxDDEConnectionList)

 
 static wxDDEClientList wxDDEClientObjects;
 static wxDDEServerList wxDDEServerObjects;
 
 static wxDDEClientList wxDDEClientObjects;
 static wxDDEServerList wxDDEServerObjects;


@@ -162,7 +138,7 @@ private:
 
 IMPLEMENT_DYNAMIC_CLASS(wxDDEServer, wxServerBase)
 IMPLEMENT_DYNAMIC_CLASS(wxDDEClient, wxClientBase)
 
 IMPLEMENT_DYNAMIC_CLASS(wxDDEServer, wxServerBase)
 IMPLEMENT_DYNAMIC_CLASS(wxDDEClient, wxClientBase)

-IMPLEMENT_CLASS(wxDDEConnection, wxConnectionBase)
+IMPLEMENT_DYNAMIC_CLASS(wxDDEConnection, wxConnectionBase)

 IMPLEMENT_DYNAMIC_CLASS(wxDDEModule, wxModule)
 
 // ============================================================================
 IMPLEMENT_DYNAMIC_CLASS(wxDDEModule, wxModule)
 
 // ============================================================================


@@ -183,7 +159,7 @@ extern void wxDDEInitialize()
         UINT rc = DdeInitialize(&DDEIdInst, callback, APPCLASS_STANDARD, 0L);
         if ( rc != DMLERR_NO_ERROR )
         {
         UINT rc = DdeInitialize(&DDEIdInst, callback, APPCLASS_STANDARD, 0L);
         if ( rc != DMLERR_NO_ERROR )
         {

-            DDELogError(_T("Failed to initialize DDE"), rc);
+            DDELogError(wxT("Failed to initialize DDE"), rc);

         }
         else
         {
         }
         else
         {


@@ -194,8 +170,10 @@ extern void wxDDEInitialize()
 
 void wxDDECleanUp()
 {
 
 void wxDDECleanUp()
 {

-    WX_CLEAR_LIST(wxDDEClientList, wxDDEClientObjects);
-    WX_CLEAR_LIST(wxDDEServerList, wxDDEServerObjects);
+    // deleting them later won't work as DDE won't be initialized any more
+    wxASSERT_MSG( wxDDEServerObjects.empty() &&
+                    wxDDEClientObjects.empty(),
+                    wxT("all DDE objects should be deleted by now") );

 
     wxAtomTable.clear();
 
 
     wxAtomTable.clear();
 


@@ -299,26 +277,45 @@ bool wxDDEServer::Create(const wxString& server)
 {
     m_serviceName = server;
 
 {
     m_serviceName = server;
 

-    if ( !DdeNameService(DDEIdInst, DDEAtomFromString(server), (HSZ)NULL, DNS_REGISTER) )
-    {
-        DDELogError(wxString::Format(_("Failed to register DDE server '%s'"),
-                                     server.c_str()));
+    HSZ hsz = DDEAtomFromString(server);

 
 

+    if ( !hsz )
+    {

         return false;
     }
 
         return false;
     }
 

-    return true;
+
+    bool success = (DdeNameService(DDEIdInst, hsz, (HSZ) NULL, DNS_REGISTER)
+        != NULL);
+
+    if (!success)
+    {
+        DDELogError(wxString::Format(_("Failed to register DDE server '%s'"),
+            server.c_str()));
+    }
+
+    DDEFreeString(hsz);
+
+    return success;

 }
 
 wxDDEServer::~wxDDEServer()
 {
 }
 
 wxDDEServer::~wxDDEServer()
 {

-    if ( !!m_serviceName )
+    if ( !m_serviceName.empty() )

     {
     {

-        if ( !DdeNameService(DDEIdInst, DDEAtomFromString(m_serviceName),
-                             (HSZ)NULL, DNS_UNREGISTER) )
+        HSZ hsz = DDEAtomFromString(m_serviceName);
+
+        if (hsz)

         {
         {

-            DDELogError(wxString::Format(_("Failed to unregister DDE server '%s'"),
-                                         m_serviceName.c_str()));
+            if ( !DdeNameService(DDEIdInst, hsz,
+                (HSZ) NULL, DNS_UNREGISTER) )
+            {
+                DDELogError(wxString::Format(
+                    _("Failed to unregister DDE server '%s'"),
+                    m_serviceName.c_str()));
+            }
+
+            DDEFreeString(hsz);

         }
     }
 
         }
     }
 


@@ -329,7 +326,6 @@ wxDDEServer::~wxDDEServer()
     {
         wxDDEConnection *connection = node->GetData();
         wxDDEConnectionList::compatibility_iterator next = node->GetNext();
     {
         wxDDEConnection *connection = node->GetData();
         wxDDEConnectionList::compatibility_iterator next = node->GetNext();

-        connection->SetConnected(false);

         connection->OnDisconnect(); // May delete the node implicitly
         node = next;
     }
         connection->OnDisconnect(); // May delete the node implicitly
         node = next;
     }


@@ -416,12 +412,35 @@ wxConnectionBase *wxDDEClient::MakeConnection(const wxString& WXUNUSED(host),
                                               const wxString& server,
                                               const wxString& topic)
 {
                                               const wxString& server,
                                               const wxString& topic)
 {

-    HCONV hConv = DdeConnect(DDEIdInst, DDEAtomFromString(server), DDEAtomFromString(topic),
-                             (PCONVCONTEXT)NULL);
+    HSZ hszServer = DDEAtomFromString(server);
+
+    if ( !hszServer )
+    {
+        return NULL;
+    }
+
+
+    HSZ hszTopic = DDEAtomFromString(topic);
+
+    if ( !hszTopic )
+    {
+        DDEFreeString(hszServer);
+        return NULL;
+    }
+
+
+    HCONV hConv = ::DdeConnect(DDEIdInst, hszServer, hszTopic,
+        (PCONVCONTEXT) NULL);
+
+    DDEFreeString(hszServer);
+    DDEFreeString(hszTopic);
+
+

     if ( !hConv )
     {
     if ( !hConv )
     {

-        DDELogError(wxString::Format(_("Failed to create connection to server '%s' on topic '%s'"),
-                                     server.c_str(), topic.c_str()));
+        DDELogError( wxString::Format(
+            _("Failed to create connection to server '%s' on topic '%s'"),
+            server.c_str(), topic.c_str()) );

     }
     else
     {
     }
     else
     {


@@ -436,7 +455,7 @@ wxConnectionBase *wxDDEClient::MakeConnection(const wxString& WXUNUSED(host),
         }
     }
 
         }
     }
 

-    return (wxConnectionBase*) NULL;
+    return NULL;

 }
 
 wxConnectionBase *wxDDEClient::OnMakeConnection()
 }
 
 wxConnectionBase *wxDDEClient::OnMakeConnection()


@@ -479,7 +498,7 @@ bool wxDDEClient::DeleteConnection(WXHCONV conv)
 // wxDDEConnection
 // ----------------------------------------------------------------------------
 
 // wxDDEConnection
 // ----------------------------------------------------------------------------
 

-wxDDEConnection::wxDDEConnection(wxChar *buffer, int size)
+wxDDEConnection::wxDDEConnection(void *buffer, size_t size)

      : wxConnectionBase(buffer, size)
 {
     m_client = NULL;
      : wxConnectionBase(buffer, size)
 {
     m_client = NULL;


@@ -518,7 +537,7 @@ bool wxDDEConnection::Disconnect()
     bool ok = DdeDisconnect(GetHConv()) != 0;
     if ( !ok )
     {
     bool ok = DdeDisconnect(GetHConv()) != 0;
     if ( !ok )
     {

-        DDELogError(_T("Failed to disconnect from DDE server gracefully"));
+        DDELogError(wxT("Failed to disconnect from DDE server gracefully"));

     }
 
     SetConnected( false );  // so we don't try and disconnect again
     }
 
     SetConnected( false );  // so we don't try and disconnect again


@@ -526,31 +545,119 @@ bool wxDDEConnection::Disconnect()
     return ok;
 }
 
     return ok;
 }
 

-bool wxDDEConnection::Execute(const wxChar *data, int size, wxIPCFormat format)
+bool
+wxDDEConnection::DoExecute(const void *data, size_t size, wxIPCFormat format)

 {
 {

-    DWORD result;
-    if (size < 0)
+    wxCHECK_MSG( format == wxIPC_TEXT ||
+                 format == wxIPC_UTF8TEXT ||
+                 format == wxIPC_UNICODETEXT,
+                 false,
+                 wxT("wxDDEServer::Execute() supports only text data") );
+
+    wxMemoryBuffer buffer;
+    LPBYTE realData = NULL;
+    size_t realSize = 0;
+    wxMBConv *conv = NULL;
+
+    // Windows only supports either ANSI or UTF-16 format depending on the
+    // build, so we need to convert the data if it doesn't use it already
+#if wxUSE_UNICODE
+    if ( format == wxIPC_TEXT )
+    {
+        conv = &wxConvLibc;
+    }
+    else if ( format == wxIPC_UTF8TEXT )

     {
     {

-        size = wxStrlen(data) + 1;
+        conv = &wxConvUTF8;

     }
     }

+    else // no conversion necessary for wxIPC_UNICODETEXT
+    {
+        realData = (LPBYTE)data;
+        realSize = size;
+    }
+
+    if ( conv )
+    {
+        const char * const text = (const char *)data;
+        const size_t len = size;
+
+        realSize = conv->ToWChar(NULL, 0, text, len);
+        if ( realSize == wxCONV_FAILED )
+            return false;
+
+        realData = (LPBYTE)buffer.GetWriteBuf(realSize*sizeof(wchar_t));
+        if ( !realData )
+            return false;
+
+        realSize = conv->ToWChar((wchar_t *)realData, realSize, text, len);
+        if ( realSize == wxCONV_FAILED )
+            return false;
+
+        // We need to pass the size of the buffer to DdeClientTransaction() and
+        // not the length of the string.
+        realSize *= sizeof(wchar_t);
+    }
+#else // !wxUSE_UNICODE
+    if ( format == wxIPC_UNICODETEXT )
+    {
+        conv = &wxConvLibc;
+    }
+    else if ( format == wxIPC_UTF8TEXT )
+    {
+        // we could implement this in theory but it's not obvious how to pass
+        // the format information and, basically, why bother -- just use
+        // Unicode build
+        wxFAIL_MSG( wxT("UTF-8 text not supported in ANSI build") );
+
+        return false;
+    }
+    else // don't convert wxIPC_TEXT
+    {
+        realData = (LPBYTE)data;
+        realSize = size;
+    }
+
+    if ( conv )
+    {
+        const wchar_t * const wtext = (const wchar_t *)data;
+        const size_t len = size/sizeof(wchar_t);
+
+        realSize = conv->FromWChar(NULL, 0, wtext, len);
+        if ( realSize == wxCONV_FAILED )
+            return false;

 
 

-    bool ok = DdeClientTransaction((LPBYTE)data, size,
-                                    GetHConv(),
-                                    NULL,
-                                    format,
-                                    XTYP_EXECUTE,
-                                    DDE_TIMEOUT,
-                                    &result) != 0;
+        realData = (LPBYTE)buffer.GetWriteBuf(realSize);
+        if ( !realData )
+            return false;
+
+        realSize = conv->FromWChar((char*)realData, realSize, wtext, len);
+        if ( realSize == wxCONV_FAILED )
+            return false;
+    }
+#endif // wxUSE_UNICODE/!wxUSE_UNICODE
+
+    DWORD result;
+    bool ok = DdeClientTransaction(realData,
+                                   realSize,
+                                   GetHConv(),
+                                   NULL,
+                                   // MSDN: if the transaction specified by
+                                   // the wType parameter does not pass data
+                                   // or is XTYP_EXECUTE, wFmt should be zero.
+                                   0,
+                                   XTYP_EXECUTE,
+                                   DDE_TIMEOUT,
+                                   &result) != 0;

 
     if ( !ok )
     {
 
     if ( !ok )
     {

-        DDELogError(_T("DDE execute request failed"));
+        DDELogError(wxT("DDE execute request failed"));

     }
 
     return ok;
 }
 
     }
 
     return ok;
 }
 

-wxChar *wxDDEConnection::Request(const wxString& item, int *size, wxIPCFormat format)
+const void *wxDDEConnection::Request(const wxString& item, size_t *size, wxIPCFormat format)

 {
     DWORD result;
 
 {
     DWORD result;
 


@@ -564,36 +671,33 @@ wxChar *wxDDEConnection::Request(const wxString& item, int *size, wxIPCFormat fo
                                                   &result);
     if ( !returned_data )
     {
                                                   &result);
     if ( !returned_data )
     {

-        DDELogError(_T("DDE data request failed"));
+        DDELogError(wxT("DDE data request failed"));

 
         return NULL;
     }
 
     DWORD len = DdeGetData(returned_data, NULL, 0, 0);
 
 
         return NULL;
     }
 
     DWORD len = DdeGetData(returned_data, NULL, 0, 0);
 

-    wxChar *data = GetBufferAtLeast( len );
+    void *data = GetBufferAtLeast(len);

     wxASSERT_MSG(data != NULL,
     wxASSERT_MSG(data != NULL,

-                 _T("Buffer too small in wxDDEConnection::Request") );
-    DdeGetData(returned_data, (LPBYTE)data, len, 0);
+                 wxT("Buffer too small in wxDDEConnection::Request") );
+    (void) DdeGetData(returned_data, (LPBYTE)data, len, 0);

 
 

-    DdeFreeDataHandle(returned_data);
+    (void) DdeFreeDataHandle(returned_data);

 
     if (size)
 
     if (size)

-        *size = (int)len;
+        *size = (size_t)len;

 
     return data;
 }
 
 
     return data;
 }
 

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

 {
     DWORD result;
 {
     DWORD result;

-    if (size < 0)
-    {
-        size = wxStrlen(data) + 1;
-    }

 
     HSZ item_atom = DDEGetAtom(item);
 
     HSZ item_atom = DDEGetAtom(item);

-    bool ok = DdeClientTransaction((LPBYTE)data, size,
+    bool ok = DdeClientTransaction((LPBYTE)data,
+                                   size,

                                    GetHConv(),
                                    item_atom, format,
                                    XTYP_POKE,
                                    GetHConv(),
                                    item_atom, format,
                                    XTYP_POKE,


@@ -646,21 +750,17 @@ bool wxDDEConnection::StopAdvise(const wxString& item)
 }
 
 // Calls that SERVER can make
 }
 
 // Calls that SERVER can make

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

 {
 {

-    if (size < 0)
-    {
-        size = wxStrlen(data) + 1;
-    }
-

     HSZ item_atom = DDEGetAtom(item);
     HSZ topic_atom = DDEGetAtom(m_topicName);
     m_sendingData = data;  // mrf: potential for scope problems here?
     m_dataSize = size;
     HSZ item_atom = DDEGetAtom(item);
     HSZ topic_atom = DDEGetAtom(m_topicName);
     m_sendingData = data;  // mrf: potential for scope problems here?
     m_dataSize = size;

-    m_dataType = format;
+    // wxIPC_PRIVATE does not succeed, so use text instead
+    m_dataType = format == wxIPC_PRIVATE ? wxIPC_TEXT : format;

 
     bool ok = DdePostAdvise(DDEIdInst, topic_atom, item_atom) != 0;
     if ( !ok )
 
     bool ok = DdePostAdvise(DDEIdInst, topic_atom, item_atom) != 0;
     if ( !ok )


@@ -671,12 +771,6 @@ bool wxDDEConnection::Advise(const wxString& item,
     return ok;
 }
 
     return ok;
 }
 

-bool wxDDEConnection::OnDisconnect()
-{
-    delete this;
-    return true;
-}
-

 // ----------------------------------------------------------------------------
 // _DDECallback
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // _DDECallback
 // ----------------------------------------------------------------------------


@@ -751,18 +845,27 @@ _DDECallback(WORD wType,
                 {
                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 
                 {
                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 

-                    wxChar *data = connection->GetBufferAtLeast( len );
+                    void *data = connection->GetBufferAtLeast(len);

                     wxASSERT_MSG(data != NULL,
                     wxASSERT_MSG(data != NULL,

-                                 _T("Buffer too small in _DDECallback (XTYP_EXECUTE)") );
+                                 wxT("Buffer too small in _DDECallback (XTYP_EXECUTE)") );

 
                     DdeGetData(hData, (LPBYTE)data, len, 0);
 
                     DdeFreeDataHandle(hData);
 
 
                     DdeGetData(hData, (LPBYTE)data, len, 0);
 
                     DdeFreeDataHandle(hData);
 

+                    // XTYP_EXECUTE can be used for text only and the text is
+                    // always in ANSI format for ANSI build and Unicode format
+                    // in Unicode build
+                    #if wxUSE_UNICODE
+                        wFmt = wxIPC_UNICODETEXT;
+                    #else
+                        wFmt = wxIPC_TEXT;
+                    #endif
+

                     if ( connection->OnExecute(connection->m_topicName,
                                                data,
                                                (int)len,
                     if ( connection->OnExecute(connection->m_topicName,
                                                data,
                                                (int)len,

-                                               (wxIPCFormat) wFmt) )
+                                               (wxIPCFormat)wFmt) )

                     {
                         return (DDERETURN)(DWORD)DDE_FACK;
                     }
                     {
                         return (DDERETURN)(DWORD)DDE_FACK;
                     }


@@ -779,15 +882,26 @@ _DDECallback(WORD wType,
                 {
                     wxString item_name = DDEStringFromAtom(hsz2);
 
                 {
                     wxString item_name = DDEStringFromAtom(hsz2);
 

-                    int user_size = -1;
-                    wxChar *data = connection->OnRequest(connection->m_topicName,
-                                                       item_name,
-                                                       &user_size,
-                                                       (wxIPCFormat) wFmt);
+                    size_t user_size = wxNO_LEN;
+                    const void *data = connection->OnRequest(connection->m_topicName,
+                                                             item_name,
+                                                             &user_size,
+                                                             (wxIPCFormat)wFmt);

                     if (data)
                     {
                     if (data)
                     {

-                        if (user_size < 0)
-                            user_size = wxStrlen((wxChar*)data) + 1;
+                      if (user_size == wxNO_LEN)
+                        switch (wFmt)
+                        {
+                          case wxIPC_TEXT:
+                          case wxIPC_UTF8TEXT:
+                            user_size = strlen((const char*)data) + 1;  // includes final NUL
+                            break;
+                          case wxIPC_UNICODETEXT:
+                            user_size = (wcslen((const wchar_t*)data) + 1) * sizeof(wchar_t);  // includes final NUL
+                            break;
+                          default:
+                            user_size = 0;
+                        }

 
                         HDDEDATA handle = DdeCreateDataHandle(DDEIdInst,
                                                               (LPBYTE)data,
 
                         HDDEDATA handle = DdeCreateDataHandle(DDEIdInst,
                                                               (LPBYTE)data,


@@ -812,9 +926,9 @@ _DDECallback(WORD wType,
 
                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 
 
                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 

-                    wxChar *data = connection->GetBufferAtLeast( len );
+                    void *data = connection->GetBufferAtLeast(len);

                     wxASSERT_MSG(data != NULL,
                     wxASSERT_MSG(data != NULL,

-                                 _T("Buffer too small in _DDECallback (XTYP_EXECUTE)") );
+                                 wxT("Buffer too small in _DDECallback (XTYP_POKE)") );

 
                     DdeGetData(hData, (LPBYTE)data, len, 0);
 
 
                     DdeGetData(hData, (LPBYTE)data, len, 0);
 


@@ -899,9 +1013,9 @@ _DDECallback(WORD wType,
 
                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 
 
                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 

-                    wxChar *data = connection->GetBufferAtLeast( len );
+                    void *data = connection->GetBufferAtLeast(len);

                     wxASSERT_MSG(data != NULL,
                     wxASSERT_MSG(data != NULL,

-                                 _T("Buffer too small in _DDECallback (XTYP_ADVDATA)") );
+                                 wxT("Buffer too small in _DDECallback (XTYP_ADVDATA)") );

 
                     DdeGetData(hData, (LPBYTE)data, len, 0);
 
 
                     DdeGetData(hData, (LPBYTE)data, len, 0);
 


@@ -945,12 +1059,15 @@ static HSZ DDEGetAtom(const wxString& str)
     return DDEAddAtom(str);
 }
 
     return DDEAddAtom(str);
 }
 

-// atom <-> strings
+/* atom <-> strings
+The returned handle has to be freed by the caller (using
+(static) DDEFreeString).
+*/

 static HSZ DDEAtomFromString(const wxString& s)
 {
 static HSZ DDEAtomFromString(const wxString& s)
 {

-    wxASSERT_MSG( DDEIdInst, _T("DDE not initialized") );
+    wxASSERT_MSG( DDEIdInst, wxT("DDE not initialized") );

 
 

-    HSZ hsz = DdeCreateStringHandle(DDEIdInst, (wxChar*) s.c_str(), DDE_CP);
+    HSZ hsz = DdeCreateStringHandle(DDEIdInst, wxMSW_CONV_LPTSTR(s), DDE_CP);

     if ( !hsz )
     {
         DDELogError(_("Failed to create DDE string"));
     if ( !hsz )
     {
         DDELogError(_("Failed to create DDE string"));


@@ -970,6 +1087,15 @@ static wxString DDEStringFromAtom(HSZ hsz)
     return s;
 }
 
     return s;
 }
 

+static void DDEFreeString(HSZ hsz)
+{
+    // DS: Failure to free a string handle might indicate there's
+    // some other severe error.
+    bool ok = (::DdeFreeStringHandle(DDEIdInst, hsz) != 0);
+    wxASSERT_MSG( ok, wxT("Failed to free DDE string handle") );
+    wxUnusedVar(ok);
+}
+

 // ----------------------------------------------------------------------------
 // error handling
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // error handling
 // ----------------------------------------------------------------------------


@@ -981,7 +1107,7 @@ static void DDELogError(const wxString& s, UINT error)
         error = DdeGetLastError(DDEIdInst);
     }
 
         error = DdeGetLastError(DDEIdInst);
     }
 

-    wxLogError(s + _T(": ") + DDEGetErrorMsg(error));
+    wxLogError(s + wxT(": ") + DDEGetErrorMsg(error));

 }
 
 static wxString DDEGetErrorMsg(UINT error)
 }
 
 static wxString DDEGetErrorMsg(UINT error)