src/msw/dde.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        msw/dde.cpp
   3 // Purpose:     DDE classes
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     01/02/97
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "dde.h"
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28     #pragma hdrstop
  29 #endif
  30
  31 #if wxUSE_IPC
  32
  33 #ifndef WX_PRECOMP
  34     #include "wx/utils.h"
  35     #include "wx/app.h"
  36 #endif
  37
  38 #include "wx/module.h"
  39 #include "wx/dde.h"
  40 #include "wx/intl.h"
  41 #include "wx/hashmap.h"
  42
  43 #include "wx/msw/private.h"
  44
  45 #include <string.h>
  46 #include <ddeml.h>
  47
  48 #ifdef __GNUWIN32_OLD__
  49     #include "wx/msw/gnuwin32/extra.h"
  50 #endif
  51
  52 // some compilers headers don't define this one (mingw32)
  53 #ifndef DMLERR_NO_ERROR
  54     #define DMLERR_NO_ERROR (0)
  55
  56     // this one is also missing from some mingw32 headers, but there is no way
  57     // to test for it (I know of) - the test for DMLERR_NO_ERROR works for me,
  58     // but is surely not the right thing to do
  59     extern "C"
  60     HDDEDATA STDCALL DdeClientTransaction(LPBYTE pData,
  61                                           DWORD cbData,
  62                                           HCONV hConv,
  63                                           HSZ hszItem,
  64                                           UINT wFmt,
  65                                           UINT wType,
  66                                           DWORD dwTimeout,
  67                                           LPDWORD pdwResult);
  68 #endif // no DMLERR_NO_ERROR
  69
  70 // ----------------------------------------------------------------------------
  71 // macros and constants
  72 // ----------------------------------------------------------------------------
  73
  74 #ifdef __WIN32__
  75     #define _EXPORT
  76 #else
  77     #define _EXPORT _export
  78 #endif
  79
  80 #if wxUSE_UNICODE
  81     #define DDE_CP      CP_WINUNICODE
  82 #else
  83     #define DDE_CP      CP_WINANSI
  84 #endif
  85
  86 #define GetHConv()       ((HCONV)m_hConv)
  87
  88 // default timeout for DDE operations (5sec)
  89 #define DDE_TIMEOUT     5000
  90
  91 // ----------------------------------------------------------------------------
  92 // private functions
  93 // ----------------------------------------------------------------------------
  94
  95 static wxDDEConnection *DDEFindConnection(HCONV hConv);
  96 static void DDEDeleteConnection(HCONV hConv);
  97 static wxDDEServer *DDEFindServer(const wxString& s);
  98
  99 extern "C" HDDEDATA EXPENTRY _EXPORT _DDECallback(WORD wType,
 100                                                   WORD wFmt,
 101                                                   HCONV hConv,
 102                                                   HSZ hsz1,
 103                                                   HSZ hsz2,
 104                                                   HDDEDATA hData,
 105                                                   DWORD lData1,
 106                                                   DWORD lData2);
 107
 108 // Add topic name to atom table before using in conversations
 109 static HSZ DDEAddAtom(const wxString& string);
 110 static HSZ DDEGetAtom(const wxString& string);
 111
 112 // string handles
 113 static HSZ DDEAtomFromString(const wxString& s);
 114 static wxString DDEStringFromAtom(HSZ hsz);
 115
 116 // error handling
 117 static wxString DDEGetErrorMsg(UINT error);
 118 static void DDELogError(const wxString& s, UINT error = DMLERR_NO_ERROR);
 119
 120 // ----------------------------------------------------------------------------
 121 // global variables
 122 // ----------------------------------------------------------------------------
 123
 124 WX_DECLARE_STRING_HASH_MAP( HSZ, wxAtomMap );
 125
 126 static DWORD DDEIdInst = 0L;
 127 static wxDDEConnection *DDECurrentlyConnecting = NULL;
 128 static wxAtomMap wxAtomTable;
 129
 130 #include "wx/listimpl.cpp"
 131
 132 WX_DEFINE_LIST(wxDDEClientList);
 133 WX_DEFINE_LIST(wxDDEServerList);
 134 WX_DEFINE_LIST(wxDDEConnectionList);
 135
 136 static wxDDEClientList wxDDEClientObjects;
 137 static wxDDEServerList wxDDEServerObjects;
 138
 139 static bool DDEInitialized = false;
 140
 141 // ----------------------------------------------------------------------------
 142 // private classes
 143 // ----------------------------------------------------------------------------
 144
 145 // A module to allow DDE cleanup without calling these functions
 146 // from app.cpp or from the user's application.
 147
 148 class wxDDEModule : public wxModule
 149 {
 150 public:
 151     wxDDEModule() {}
 152     bool OnInit() { return true; }
 153     void OnExit() { wxDDECleanUp(); }
 154
 155 private:
 156     DECLARE_DYNAMIC_CLASS(wxDDEModule)
 157 };
 158
 159 // ----------------------------------------------------------------------------
 160 // wxWin macros
 161 // ----------------------------------------------------------------------------
 162
 163 IMPLEMENT_DYNAMIC_CLASS(wxDDEServer, wxServerBase)
 164 IMPLEMENT_DYNAMIC_CLASS(wxDDEClient, wxClientBase)
 165 IMPLEMENT_CLASS(wxDDEConnection, wxConnectionBase)
 166 IMPLEMENT_DYNAMIC_CLASS(wxDDEModule, wxModule)
 167
 168 // ============================================================================
 169 // implementation
 170 // ============================================================================
 171
 172 // ----------------------------------------------------------------------------
 173 // initialization and cleanup
 174 // ----------------------------------------------------------------------------
 175
 176 extern void wxDDEInitialize()
 177 {
 178     if ( !DDEInitialized )
 179     {
 180         // Should insert filter flags
 181         PFNCALLBACK callback = (PFNCALLBACK)
 182             MakeProcInstance((FARPROC)_DDECallback, wxGetInstance());
 183         UINT rc = DdeInitialize(&DDEIdInst, callback, APPCLASS_STANDARD, 0L);
 184         if ( rc != DMLERR_NO_ERROR )
 185         {
 186             DDELogError(_T("Failed to initialize DDE"), rc);
 187         }
 188         else
 189         {
 190             DDEInitialized = true;
 191         }
 192     }
 193 }
 194
 195 void wxDDECleanUp()
 196 {
 197     WX_CLEAR_LIST(wxDDEClientList, wxDDEClientObjects);
 198     WX_CLEAR_LIST(wxDDEServerList, wxDDEServerObjects);
 199
 200     wxAtomTable.clear();
 201
 202     if ( DDEIdInst != 0 )
 203     {
 204         DdeUninitialize(DDEIdInst);
 205         DDEIdInst = 0;
 206     }
 207 }
 208
 209 // ----------------------------------------------------------------------------
 210 // functions working with the global connection list(s)
 211 // ----------------------------------------------------------------------------
 212
 213 // Global find connection
 214 static wxDDEConnection *DDEFindConnection(HCONV hConv)
 215 {
 216     wxDDEServerList::compatibility_iterator serverNode = wxDDEServerObjects.GetFirst();
 217     wxDDEConnection *found = NULL;
 218     while (serverNode && !found)
 219     {
 220         wxDDEServer *object = serverNode->GetData();
 221         found = object->FindConnection((WXHCONV) hConv);
 222         serverNode = serverNode->GetNext();
 223     }
 224
 225     if (found)
 226     {
 227         return found;
 228     }
 229
 230     wxDDEClientList::compatibility_iterator clientNode = wxDDEClientObjects.GetFirst();
 231     while (clientNode && !found)
 232     {
 233         wxDDEClient *object = clientNode->GetData();
 234         found = object->FindConnection((WXHCONV) hConv);
 235         clientNode = clientNode->GetNext();
 236     }
 237     return found;
 238 }
 239
 240 // Global delete connection
 241 static void DDEDeleteConnection(HCONV hConv)
 242 {
 243     wxDDEServerList::compatibility_iterator serverNode = wxDDEServerObjects.GetFirst();
 244     bool found = false;
 245     while (serverNode && !found)
 246     {
 247         wxDDEServer *object = serverNode->GetData();
 248         found = object->DeleteConnection((WXHCONV) hConv);
 249         serverNode = serverNode->GetNext();
 250     }
 251     if (found)
 252     {
 253         return;
 254     }
 255
 256     wxDDEClientList::compatibility_iterator clientNode = wxDDEClientObjects.GetFirst();
 257     while (clientNode && !found)
 258     {
 259         wxDDEClient *object = clientNode->GetData();
 260         found = object->DeleteConnection((WXHCONV) hConv);
 261         clientNode = clientNode->GetNext();
 262     }
 263 }
 264
 265 // Find a server from a service name
 266 static wxDDEServer *DDEFindServer(const wxString& s)
 267 {
 268     wxDDEServerList::compatibility_iterator node = wxDDEServerObjects.GetFirst();
 269     wxDDEServer *found = NULL;
 270     while (node && !found)
 271     {
 272         wxDDEServer *object = node->GetData();
 273
 274         if (object->GetServiceName() == s)
 275         {
 276             found = object;
 277         }
 278         else
 279         {
 280             node = node->GetNext();
 281         }
 282     }
 283
 284     return found;
 285 }
 286
 287 // ----------------------------------------------------------------------------
 288 // wxDDEServer
 289 // ----------------------------------------------------------------------------
 290
 291 wxDDEServer::wxDDEServer()
 292 {
 293     wxDDEInitialize();
 294
 295     wxDDEServerObjects.Append(this);
 296 }
 297
 298 bool wxDDEServer::Create(const wxString& server)
 299 {
 300     m_serviceName = server;
 301
 302     if ( !DdeNameService(DDEIdInst, DDEAtomFromString(server), (HSZ)NULL, DNS_REGISTER) )
 303     {
 304         DDELogError(wxString::Format(_("Failed to register DDE server '%s'"),
 305                                      server.c_str()));
 306
 307         return false;
 308     }
 309
 310     return true;
 311 }
 312
 313 wxDDEServer::~wxDDEServer()
 314 {
 315     if ( !!m_serviceName )
 316     {
 317         if ( !DdeNameService(DDEIdInst, DDEAtomFromString(m_serviceName),
 318                              (HSZ)NULL, DNS_UNREGISTER) )
 319         {
 320             DDELogError(wxString::Format(_("Failed to unregister DDE server '%s'"),
 321                                          m_serviceName.c_str()));
 322         }
 323     }
 324
 325     wxDDEServerObjects.DeleteObject(this);
 326
 327     wxDDEConnectionList::compatibility_iterator node = m_connections.GetFirst();
 328     while (node)
 329     {
 330         wxDDEConnection *connection = node->GetData();
 331         wxDDEConnectionList::compatibility_iterator next = node->GetNext();
 332         connection->SetConnected(false);
 333         connection->OnDisconnect(); // May delete the node implicitly
 334         node = next;
 335     }
 336
 337     // If any left after this, delete them
 338     node = m_connections.GetFirst();
 339     while (node)
 340     {
 341         wxDDEConnection *connection = node->GetData();
 342         wxDDEConnectionList::compatibility_iterator next = node->GetNext();
 343         delete connection;
 344         node = next;
 345     }
 346 }
 347
 348 wxConnectionBase *wxDDEServer::OnAcceptConnection(const wxString& /* topic */)
 349 {
 350     return new wxDDEConnection;
 351 }
 352
 353 wxDDEConnection *wxDDEServer::FindConnection(WXHCONV conv)
 354 {
 355     wxDDEConnectionList::compatibility_iterator node = m_connections.GetFirst();
 356     wxDDEConnection *found = NULL;
 357     while (node && !found)
 358     {
 359         wxDDEConnection *connection = node->GetData();
 360         if (connection->m_hConv == conv)
 361             found = connection;
 362         else node = node->GetNext();
 363     }
 364     return found;
 365 }
 366
 367 // Only delete the entry in the map, not the actual connection
 368 bool wxDDEServer::DeleteConnection(WXHCONV conv)
 369 {
 370     wxDDEConnectionList::compatibility_iterator node = m_connections.GetFirst();
 371     while (node)
 372     {
 373         wxDDEConnection *connection = node->GetData();
 374         if (connection->m_hConv == conv)
 375         {
 376             m_connections.Erase(node);
 377             return true;
 378         }
 379         else
 380         {
 381             node = node->GetNext();
 382         }
 383     }
 384     return false;
 385 }
 386
 387 // ----------------------------------------------------------------------------
 388 // wxDDEClient
 389 // ----------------------------------------------------------------------------
 390
 391 wxDDEClient::wxDDEClient()
 392 {
 393     wxDDEInitialize();
 394
 395     wxDDEClientObjects.Append(this);
 396 }
 397
 398 wxDDEClient::~wxDDEClient()
 399 {
 400     wxDDEClientObjects.DeleteObject(this);
 401     wxDDEConnectionList::compatibility_iterator node = m_connections.GetFirst();
 402     while (node)
 403     {
 404         wxDDEConnection *connection = node->GetData();
 405         delete connection;  // Deletes the node implicitly (see ~wxDDEConnection)
 406         node = m_connections.GetFirst();
 407     }
 408 }
 409
 410 bool wxDDEClient::ValidHost(const wxString& /* host */)
 411 {
 412     return true;
 413 }
 414
 415 wxConnectionBase *wxDDEClient::MakeConnection(const wxString& WXUNUSED(host),
 416                                               const wxString& server,
 417                                               const wxString& topic)
 418 {
 419     HCONV hConv = DdeConnect(DDEIdInst, DDEAtomFromString(server), DDEAtomFromString(topic),
 420                              (PCONVCONTEXT)NULL);
 421     if ( !hConv )
 422     {
 423         DDELogError(wxString::Format(_("Failed to create connection to server '%s' on topic '%s'"),
 424                                      server.c_str(), topic.c_str()));
 425     }
 426     else
 427     {
 428         wxDDEConnection *connection = (wxDDEConnection*) OnMakeConnection();
 429         if (connection)
 430         {
 431             connection->m_hConv = (WXHCONV) hConv;
 432             connection->m_topicName = topic;
 433             connection->m_client = this;
 434             m_connections.Append(connection);
 435             return connection;
 436         }
 437     }
 438
 439     return (wxConnectionBase*) NULL;
 440 }
 441
 442 wxConnectionBase *wxDDEClient::OnMakeConnection()
 443 {
 444     return new wxDDEConnection;
 445 }
 446
 447 wxDDEConnection *wxDDEClient::FindConnection(WXHCONV conv)
 448 {
 449     wxDDEConnectionList::compatibility_iterator node = m_connections.GetFirst();
 450     wxDDEConnection *found = NULL;
 451     while (node && !found)
 452     {
 453         wxDDEConnection *connection = node->GetData();
 454         if (connection->m_hConv == conv)
 455             found = connection;
 456         else node = node->GetNext();
 457     }
 458     return found;
 459 }
 460
 461 // Only delete the entry in the map, not the actual connection
 462 bool wxDDEClient::DeleteConnection(WXHCONV conv)
 463 {
 464     wxDDEConnectionList::compatibility_iterator node = m_connections.GetFirst();
 465     while (node)
 466     {
 467         wxDDEConnection *connection = node->GetData();
 468         if (connection->m_hConv == conv)
 469         {
 470             m_connections.Erase(node);
 471             return true;
 472         }
 473         else node = node->GetNext();
 474     }
 475     return false;
 476 }
 477
 478 // ----------------------------------------------------------------------------
 479 // wxDDEConnection
 480 // ----------------------------------------------------------------------------
 481
 482 wxDDEConnection::wxDDEConnection(wxChar *buffer, int size)
 483      : wxConnectionBase(buffer, size)
 484 {
 485     m_client = NULL;
 486     m_server = NULL;
 487
 488     m_hConv = 0;
 489     m_sendingData = NULL;
 490 }
 491
 492 wxDDEConnection::wxDDEConnection()
 493      : wxConnectionBase()
 494 {
 495     m_hConv = 0;
 496     m_sendingData = NULL;
 497     m_server = NULL;
 498     m_client = NULL;
 499 }
 500
 501 wxDDEConnection::~wxDDEConnection()
 502 {
 503     Disconnect();
 504     if (m_server)
 505         m_server->GetConnections().DeleteObject(this);
 506     else
 507         m_client->GetConnections().DeleteObject(this);
 508 }
 509
 510 // Calls that CLIENT can make
 511 bool wxDDEConnection::Disconnect()
 512 {
 513     if ( !GetConnected() )
 514         return true;
 515
 516     DDEDeleteConnection(GetHConv());
 517
 518     bool ok = DdeDisconnect(GetHConv()) != 0;
 519     if ( !ok )
 520     {
 521         DDELogError(_T("Failed to disconnect from DDE server gracefully"));
 522     }
 523
 524     SetConnected( false );  // so we don't try and disconnect again
 525
 526     return ok;
 527 }
 528
 529 bool wxDDEConnection::Execute(const wxChar *data, int size, wxIPCFormat format)
 530 {
 531     DWORD result;
 532     if (size < 0)
 533     {
 534         size = wxStrlen(data) + 1;
 535     }
 536
 537     bool ok = DdeClientTransaction((LPBYTE)data, size,
 538                                     GetHConv(),
 539                                     NULL,
 540                                     format,
 541                                     XTYP_EXECUTE,
 542                                     DDE_TIMEOUT,
 543                                     &result) != 0;
 544
 545     if ( !ok )
 546     {
 547         DDELogError(_T("DDE execute request failed"));
 548     }
 549
 550     return ok;
 551 }
 552
 553 wxChar *wxDDEConnection::Request(const wxString& item, int *size, wxIPCFormat format)
 554 {
 555     DWORD result;
 556
 557     HSZ atom = DDEGetAtom(item);
 558
 559     HDDEDATA returned_data = DdeClientTransaction(NULL, 0,
 560                                                   GetHConv(),
 561                                                   atom, format,
 562                                                   XTYP_REQUEST,
 563                                                   DDE_TIMEOUT,
 564                                                   &result);
 565     if ( !returned_data )
 566     {
 567         DDELogError(_T("DDE data request failed"));
 568
 569         return NULL;
 570     }
 571
 572     DWORD len = DdeGetData(returned_data, NULL, 0, 0);
 573
 574     wxChar *data = GetBufferAtLeast( len );
 575     wxASSERT_MSG(data != NULL,
 576                  _T("Buffer too small in wxDDEConnection::Request") );
 577     DdeGetData(returned_data, (LPBYTE)data, len, 0);
 578
 579     DdeFreeDataHandle(returned_data);
 580
 581     if (size)
 582         *size = (int)len;
 583
 584     return data;
 585 }
 586
 587 bool wxDDEConnection::Poke(const wxString& item, wxChar *data, int size, wxIPCFormat format)
 588 {
 589     DWORD result;
 590     if (size < 0)
 591     {
 592         size = wxStrlen(data) + 1;
 593     }
 594
 595     HSZ item_atom = DDEGetAtom(item);
 596     bool ok = DdeClientTransaction((LPBYTE)data, size,
 597                                    GetHConv(),
 598                                    item_atom, format,
 599                                    XTYP_POKE,
 600                                    DDE_TIMEOUT,
 601                                    &result) != 0;
 602     if ( !ok )
 603     {
 604         DDELogError(_("DDE poke request failed"));
 605     }
 606
 607     return ok;
 608 }
 609
 610 bool wxDDEConnection::StartAdvise(const wxString& item)
 611 {
 612     DWORD result;
 613     HSZ atom = DDEGetAtom(item);
 614
 615     bool ok = DdeClientTransaction(NULL, 0,
 616                                    GetHConv(),
 617                                    atom, CF_TEXT,
 618                                    XTYP_ADVSTART,
 619                                    DDE_TIMEOUT,
 620                                    &result) != 0;
 621     if ( !ok )
 622     {
 623         DDELogError(_("Failed to establish an advise loop with DDE server"));
 624     }
 625
 626     return ok;
 627 }
 628
 629 bool wxDDEConnection::StopAdvise(const wxString& item)
 630 {
 631     DWORD result;
 632     HSZ atom = DDEGetAtom(item);
 633
 634     bool ok = DdeClientTransaction(NULL, 0,
 635                                    GetHConv(),
 636                                    atom, CF_TEXT,
 637                                    XTYP_ADVSTOP,
 638                                    DDE_TIMEOUT,
 639                                    &result) != 0;
 640     if ( !ok )
 641     {
 642         DDELogError(_("Failed to terminate the advise loop with DDE server"));
 643     }
 644
 645     return ok;
 646 }
 647
 648 // Calls that SERVER can make
 649 bool wxDDEConnection::Advise(const wxString& item,
 650                              wxChar *data,
 651                              int size,
 652                              wxIPCFormat format)
 653 {
 654     if (size < 0)
 655     {
 656         size = wxStrlen(data) + 1;
 657     }
 658
 659     HSZ item_atom = DDEGetAtom(item);
 660     HSZ topic_atom = DDEGetAtom(m_topicName);
 661     m_sendingData = data;  // mrf: potential for scope problems here?
 662     m_dataSize = size;
 663     m_dataType = format;
 664
 665     bool ok = DdePostAdvise(DDEIdInst, topic_atom, item_atom) != 0;
 666     if ( !ok )
 667     {
 668         DDELogError(_("Failed to send DDE advise notification"));
 669     }
 670
 671     return ok;
 672 }
 673
 674 bool wxDDEConnection::OnDisconnect()
 675 {
 676     delete this;
 677     return true;
 678 }
 679
 680 // ----------------------------------------------------------------------------
 681 // _DDECallback
 682 // ----------------------------------------------------------------------------
 683
 684 #define DDERETURN HDDEDATA
 685
 686 HDDEDATA EXPENTRY _EXPORT
 687 _DDECallback(WORD wType,
 688              WORD wFmt,
 689              HCONV hConv,
 690              HSZ hsz1,
 691              HSZ hsz2,
 692              HDDEDATA hData,
 693              DWORD WXUNUSED(lData1),
 694              DWORD WXUNUSED(lData2))
 695 {
 696     switch (wType)
 697     {
 698         case XTYP_CONNECT:
 699             {
 700                 wxString topic = DDEStringFromAtom(hsz1),
 701                          srv = DDEStringFromAtom(hsz2);
 702                 wxDDEServer *server = DDEFindServer(srv);
 703                 if (server)
 704                 {
 705                     wxDDEConnection *connection =
 706                         (wxDDEConnection*) server->OnAcceptConnection(topic);
 707                     if (connection)
 708                     {
 709                         connection->m_server = server;
 710                         server->GetConnections().Append(connection);
 711                         connection->m_hConv = 0;
 712                         connection->m_topicName = topic;
 713                         DDECurrentlyConnecting = connection;
 714                         return (DDERETURN)(DWORD)true;
 715                     }
 716                 }
 717                 break;
 718             }
 719
 720         case XTYP_CONNECT_CONFIRM:
 721             {
 722                 if (DDECurrentlyConnecting)
 723                 {
 724                     DDECurrentlyConnecting->m_hConv = (WXHCONV) hConv;
 725                     DDECurrentlyConnecting = NULL;
 726                     return (DDERETURN)(DWORD)true;
 727                 }
 728                 break;
 729             }
 730
 731         case XTYP_DISCONNECT:
 732             {
 733                 wxDDEConnection *connection = DDEFindConnection(hConv);
 734                 if (connection)
 735                 {
 736                     connection->SetConnected( false );
 737                     if (connection->OnDisconnect())
 738                     {
 739                         DDEDeleteConnection(hConv);  // Delete mapping: hConv => connection
 740                         return (DDERETURN)(DWORD)true;
 741                     }
 742                 }
 743                 break;
 744             }
 745
 746         case XTYP_EXECUTE:
 747             {
 748                 wxDDEConnection *connection = DDEFindConnection(hConv);
 749
 750                 if (connection)
 751                 {
 752                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 753
 754                     wxChar *data = connection->GetBufferAtLeast( len );
 755                     wxASSERT_MSG(data != NULL,
 756                                  _T("Buffer too small in _DDECallback (XTYP_EXECUTE)") );
 757
 758                     DdeGetData(hData, (LPBYTE)data, len, 0);
 759
 760                     DdeFreeDataHandle(hData);
 761
 762                     if ( connection->OnExecute(connection->m_topicName,
 763                                                data,
 764                                                (int)len,
 765                                                (wxIPCFormat) wFmt) )
 766                     {
 767                         return (DDERETURN)(DWORD)DDE_FACK;
 768                     }
 769                 }
 770
 771                 return (DDERETURN)DDE_FNOTPROCESSED;
 772             }
 773
 774         case XTYP_REQUEST:
 775             {
 776                 wxDDEConnection *connection = DDEFindConnection(hConv);
 777
 778                 if (connection)
 779                 {
 780                     wxString item_name = DDEStringFromAtom(hsz2);
 781
 782                     int user_size = -1;
 783                     wxChar *data = connection->OnRequest(connection->m_topicName,
 784                                                        item_name,
 785                                                        &user_size,
 786                                                        (wxIPCFormat) wFmt);
 787                     if (data)
 788                     {
 789                         if (user_size < 0)
 790                             user_size = wxStrlen((wxChar*)data) + 1;
 791
 792                         HDDEDATA handle = DdeCreateDataHandle(DDEIdInst,
 793                                                               (LPBYTE)data,
 794                                                               user_size,
 795                                                               0,
 796                                                               hsz2,
 797                                                               wFmt,
 798                                                               0);
 799                         return (DDERETURN)handle;
 800                     }
 801                 }
 802                 break;
 803             }
 804
 805         case XTYP_POKE:
 806             {
 807                 wxDDEConnection *connection = DDEFindConnection(hConv);
 808
 809                 if (connection)
 810                 {
 811                     wxString item_name = DDEStringFromAtom(hsz2);
 812
 813                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 814
 815                     wxChar *data = connection->GetBufferAtLeast( len );
 816                     wxASSERT_MSG(data != NULL,
 817                                  _T("Buffer too small in _DDECallback (XTYP_EXECUTE)") );
 818
 819                     DdeGetData(hData, (LPBYTE)data, len, 0);
 820
 821                     DdeFreeDataHandle(hData);
 822
 823                     connection->OnPoke(connection->m_topicName,
 824                                        item_name,
 825                                        data,
 826                                        (int)len,
 827                                        (wxIPCFormat) wFmt);
 828
 829                     return (DDERETURN)DDE_FACK;
 830                 }
 831                 else
 832                 {
 833                     return (DDERETURN)DDE_FNOTPROCESSED;
 834                 }
 835             }
 836
 837         case XTYP_ADVSTART:
 838             {
 839                 wxDDEConnection *connection = DDEFindConnection(hConv);
 840
 841                 if (connection)
 842                 {
 843                     wxString item_name = DDEStringFromAtom(hsz2);
 844
 845                     return (DDERETURN)connection->
 846                                 OnStartAdvise(connection->m_topicName, item_name);
 847                 }
 848
 849                 break;
 850             }
 851
 852         case XTYP_ADVSTOP:
 853             {
 854                 wxDDEConnection *connection = DDEFindConnection(hConv);
 855
 856                 if (connection)
 857                 {
 858                     wxString item_name = DDEStringFromAtom(hsz2);
 859
 860                     return (DDERETURN)connection->
 861                         OnStopAdvise(connection->m_topicName, item_name);
 862                 }
 863
 864                 break;
 865             }
 866
 867         case XTYP_ADVREQ:
 868             {
 869                 wxDDEConnection *connection = DDEFindConnection(hConv);
 870
 871                 if (connection && connection->m_sendingData)
 872                 {
 873                     HDDEDATA data = DdeCreateDataHandle
 874                                     (
 875                                         DDEIdInst,
 876                                         (LPBYTE)connection->m_sendingData,
 877                                         connection->m_dataSize,
 878                                         0,
 879                                         hsz2,
 880                                         connection->m_dataType,
 881                                         0
 882                                     );
 883
 884                     connection->m_sendingData = NULL;
 885
 886                     return (DDERETURN)data;
 887                 }
 888
 889                 break;
 890             }
 891
 892         case XTYP_ADVDATA:
 893             {
 894                 wxDDEConnection *connection = DDEFindConnection(hConv);
 895
 896                 if (connection)
 897                 {
 898                     wxString item_name = DDEStringFromAtom(hsz2);
 899
 900                     DWORD len = DdeGetData(hData, NULL, 0, 0);
 901
 902                     wxChar *data = connection->GetBufferAtLeast( len );
 903                     wxASSERT_MSG(data != NULL,
 904                                  _T("Buffer too small in _DDECallback (XTYP_ADVDATA)") );
 905
 906                     DdeGetData(hData, (LPBYTE)data, len, 0);
 907
 908                     DdeFreeDataHandle(hData);
 909                     if ( connection->OnAdvise(connection->m_topicName,
 910                                               item_name,
 911                                               data,
 912                                               (int)len,
 913                                               (wxIPCFormat) wFmt) )
 914                     {
 915                         return (DDERETURN)(DWORD)DDE_FACK;
 916                     }
 917                 }
 918
 919                 return (DDERETURN)DDE_FNOTPROCESSED;
 920             }
 921     }
 922
 923     return (DDERETURN)0;
 924 }
 925
 926 // ----------------------------------------------------------------------------
 927 // DDE strings and atoms
 928 // ----------------------------------------------------------------------------
 929
 930 // Atom table stuff
 931 static HSZ DDEAddAtom(const wxString& str)
 932 {
 933     HSZ atom = DDEAtomFromString(str);
 934     wxAtomTable[str] = atom;
 935     return atom;
 936 }
 937
 938 static HSZ DDEGetAtom(const wxString& str)
 939 {
 940     wxAtomMap::iterator it = wxAtomTable.find(str);
 941
 942     if (it != wxAtomTable.end())
 943         return it->second;
 944
 945     return DDEAddAtom(str);
 946 }
 947
 948 // atom <-> strings
 949 static HSZ DDEAtomFromString(const wxString& s)
 950 {
 951     wxASSERT_MSG( DDEIdInst, _T("DDE not initialized") );
 952
 953     HSZ hsz = DdeCreateStringHandle(DDEIdInst, (wxChar*) s.c_str(), DDE_CP);
 954     if ( !hsz )
 955     {
 956         DDELogError(_("Failed to create DDE string"));
 957     }
 958
 959     return hsz;
 960 }
 961
 962 static wxString DDEStringFromAtom(HSZ hsz)
 963 {
 964     // all DDE strings are normally limited to 255 bytes
 965     static const size_t len = 256;
 966
 967     wxString s;
 968     (void)DdeQueryString(DDEIdInst, hsz, s.GetWriteBuf(len), len, DDE_CP);
 969     s.UngetWriteBuf();
 970
 971     return s;
 972 }
 973
 974 // ----------------------------------------------------------------------------
 975 // error handling
 976 // ----------------------------------------------------------------------------
 977
 978 static void DDELogError(const wxString& s, UINT error)
 979 {
 980     if ( !error )
 981     {
 982         error = DdeGetLastError(DDEIdInst);
 983     }
 984
 985     wxLogError(s + _T(": ") + DDEGetErrorMsg(error));
 986 }
 987
 988 static wxString DDEGetErrorMsg(UINT error)
 989 {
 990     wxString err;
 991     switch ( error )
 992     {
 993         case DMLERR_NO_ERROR:
 994             err = _("no DDE error.");
 995             break;
 996
 997         case DMLERR_ADVACKTIMEOUT:
 998             err = _("a request for a synchronous advise transaction has timed out.");
 999             break;
1000         case DMLERR_BUSY:
1001             err = _("the response to the transaction caused the DDE_FBUSY bit to be set.");
1002             break;
1003         case DMLERR_DATAACKTIMEOUT:
1004             err = _("a request for a synchronous data transaction has timed out.");
1005             break;
1006         case DMLERR_DLL_NOT_INITIALIZED:
1007             err = _("a DDEML function was called without first calling the DdeInitialize function,\nor an invalid instance identifier\nwas passed to a DDEML function.");
1008             break;
1009         case DMLERR_DLL_USAGE:
1010             err = _("an application initialized as APPCLASS_MONITOR has\nattempted to perform a DDE transaction,\nor an application initialized as APPCMD_CLIENTONLY has \nattempted to perform server transactions.");
1011             break;
1012         case DMLERR_EXECACKTIMEOUT:
1013             err = _("a request for a synchronous execute transaction has timed out.");
1014             break;
1015         case DMLERR_INVALIDPARAMETER:
1016             err = _("a parameter failed to be validated by the DDEML.");
1017             break;
1018         case DMLERR_LOW_MEMORY:
1019             err = _("a DDEML application has created a prolonged race condition.");
1020             break;
1021         case DMLERR_MEMORY_ERROR:
1022             err = _("a memory allocation failed.");
1023             break;
1024         case DMLERR_NO_CONV_ESTABLISHED:
1025             err = _("a client's attempt to establish a conversation has failed.");
1026             break;
1027         case DMLERR_NOTPROCESSED:
1028             err = _("a transaction failed.");
1029             break;
1030         case DMLERR_POKEACKTIMEOUT:
1031             err = _("a request for a synchronous poke transaction has timed out.");
1032             break;
1033         case DMLERR_POSTMSG_FAILED:
1034             err = _("an internal call to the PostMessage function has failed. ");
1035             break;
1036         case DMLERR_REENTRANCY:
1037             err = _("reentrancy problem.");
1038             break;
1039         case DMLERR_SERVER_DIED:
1040             err = _("a server-side transaction was attempted on a conversation\nthat was terminated by the client, or the server\nterminated before completing a transaction.");
1041             break;
1042         case DMLERR_SYS_ERROR:
1043             err = _("an internal error has occurred in the DDEML.");
1044             break;
1045         case DMLERR_UNADVACKTIMEOUT:
1046             err = _("a request to end an advise transaction has timed out.");
1047             break;
1048         case DMLERR_UNFOUND_QUEUE_ID:
1049             err = _("an invalid transaction identifier was passed to a DDEML function.\nOnce the application has returned from an XTYP_XACT_COMPLETE callback,\nthe transaction identifier for that callback is no longer valid.");
1050             break;
1051         default:
1052             err.Printf(_("Unknown DDE error %08x"), error);
1053     }
1054
1055     return err;
1056 }
1057
1058 #endif
1059   // wxUSE_IPC