src/msw/utilsexc.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        msw/utilsexec.cpp
   3 // Purpose:     wxExecute implementation for MSW
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998-2002 wxWindows dev team
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation
  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 #ifndef WX_PRECOMP
  32     #include "wx/utils.h"
  33     #include "wx/app.h"
  34     #include "wx/intl.h"
  35     #include "wx/log.h"
  36 #endif
  37
  38 #ifdef __WIN32__
  39     #include "wx/stream.h"
  40     #include "wx/process.h"
  41 #endif
  42
  43 #include "wx/apptrait.h"
  44
  45 #include "wx/msw/private.h"
  46
  47 #include <ctype.h>
  48
  49 #if !defined(__GNUWIN32__) && !defined(__SALFORDC__) && !defined(__WXMICROWIN__)
  50     #include <direct.h>
  51 #ifndef __MWERKS__
  52     #include <dos.h>
  53 #endif
  54 #endif
  55
  56 #if defined(__GNUWIN32__)
  57     #include <sys/unistd.h>
  58     #include <sys/stat.h>
  59 #endif
  60
  61 #if defined(__WIN32__) && !defined(__WXMICROWIN__)
  62 #ifndef __UNIX__
  63     #include <io.h>
  64 #endif
  65
  66 #ifndef __GNUWIN32__
  67 #include <shellapi.h>
  68 #endif
  69 #endif
  70
  71 #include <stdio.h>
  72 #include <stdlib.h>
  73 #include <string.h>
  74 #ifndef __WATCOMC__
  75     #if !(defined(_MSC_VER) && (_MSC_VER > 800))
  76         #include <errno.h>
  77     #endif
  78 #endif
  79 #include <stdarg.h>
  80
  81 #if wxUSE_IPC
  82     #include "wx/dde.h"         // for WX_DDE hack in wxExecute
  83 #endif // wxUSE_IPC
  84
  85 // ----------------------------------------------------------------------------
  86 // constants
  87 // ----------------------------------------------------------------------------
  88
  89 // this message is sent when the process we're waiting for terminates
  90 #define wxWM_PROC_TERMINATED (WM_USER + 10000)
  91
  92 // ----------------------------------------------------------------------------
  93 // this module globals
  94 // ----------------------------------------------------------------------------
  95
  96 // we need to create a hidden window to receive the process termination
  97 // notifications and for this we need a (Win) class name for it which we will
  98 // register the first time it's needed
  99 static const wxChar *gs_classForHiddenWindow = NULL;
 100
 101 // ----------------------------------------------------------------------------
 102 // private types
 103 // ----------------------------------------------------------------------------
 104
 105 // structure describing the process we're being waiting for
 106 struct wxExecuteData
 107 {
 108 public:
 109     ~wxExecuteData()
 110     {
 111 #ifndef __WIN16__
 112         if ( !::CloseHandle(hProcess) )
 113         {
 114             wxLogLastError(wxT("CloseHandle(hProcess)"));
 115         }
 116 #endif
 117     }
 118
 119     HWND       hWnd;          // window to send wxWM_PROC_TERMINATED to
 120     HANDLE     hProcess;      // handle of the process
 121     DWORD      dwProcessId;   // pid of the process
 122     wxProcess *handler;
 123     DWORD      dwExitCode;    // the exit code of the process
 124     bool       state;         // set to FALSE when the process finishes
 125 };
 126
 127 #if defined(__WIN32__) && wxUSE_STREAMS
 128
 129 // ----------------------------------------------------------------------------
 130 // wxPipeStreams
 131 // ----------------------------------------------------------------------------
 132
 133 class wxPipeInputStream: public wxInputStream
 134 {
 135 public:
 136     wxPipeInputStream(HANDLE hInput);
 137     virtual ~wxPipeInputStream();
 138
 139     // returns TRUE if the pipe is still opened
 140     bool IsOpened() const { return m_hInput != INVALID_HANDLE_VALUE; }
 141
 142     // returns TRUE if there is any data to be read from the pipe
 143     virtual bool CanRead() const;
 144
 145 protected:
 146     size_t OnSysRead(void *buffer, size_t len);
 147
 148 protected:
 149     HANDLE m_hInput;
 150
 151     DECLARE_NO_COPY_CLASS(wxPipeInputStream)
 152 };
 153
 154 class wxPipeOutputStream: public wxOutputStream
 155 {
 156 public:
 157     wxPipeOutputStream(HANDLE hOutput);
 158     virtual ~wxPipeOutputStream();
 159
 160 protected:
 161     size_t OnSysWrite(const void *buffer, size_t len);
 162
 163 protected:
 164     HANDLE m_hOutput;
 165
 166     DECLARE_NO_COPY_CLASS(wxPipeOutputStream)
 167 };
 168
 169 // define this to let wxexec.cpp know that we know what we're doing
 170 #define _WX_USED_BY_WXEXECUTE_
 171 #include "../common/execcmn.cpp"
 172
 173 // ----------------------------------------------------------------------------
 174 // wxPipe represents a Win32 anonymous pipe
 175 // ----------------------------------------------------------------------------
 176
 177 class wxPipe
 178 {
 179 public:
 180     // the symbolic names for the pipe ends
 181     enum Direction
 182     {
 183         Read,
 184         Write
 185     };
 186
 187     // default ctor doesn't do anything
 188     wxPipe() { m_handles[Read] = m_handles[Write] = INVALID_HANDLE_VALUE; }
 189
 190     // create the pipe, return TRUE if ok, FALSE on error
 191     bool Create()
 192     {
 193         // default secutiry attributes
 194         SECURITY_ATTRIBUTES security;
 195
 196         security.nLength              = sizeof(security);
 197         security.lpSecurityDescriptor = NULL;
 198         security.bInheritHandle       = TRUE; // to pass it to the child
 199
 200         if ( !::CreatePipe(&m_handles[0], &m_handles[1], &security, 0) )
 201         {
 202             wxLogSysError(_("Failed to create an anonymous pipe"));
 203
 204             return FALSE;
 205         }
 206
 207         return TRUE;
 208     }
 209
 210     // return TRUE if we were created successfully
 211     bool IsOk() const { return m_handles[Read] != INVALID_HANDLE_VALUE; }
 212
 213     // return the descriptor for one of the pipe ends
 214     HANDLE operator[](Direction which) const
 215     {
 216         wxASSERT_MSG( which >= 0 && (size_t)which < WXSIZEOF(m_handles),
 217                       _T("invalid pipe index") );
 218
 219         return m_handles[which];
 220     }
 221
 222     // detach a descriptor, meaning that the pipe dtor won't close it, and
 223     // return it
 224     HANDLE Detach(Direction which)
 225     {
 226         wxASSERT_MSG( which >= 0 && (size_t)which < WXSIZEOF(m_handles),
 227                       _T("invalid pipe index") );
 228
 229         HANDLE handle = m_handles[which];
 230         m_handles[which] = INVALID_HANDLE_VALUE;
 231
 232         return handle;
 233     }
 234
 235     // close the pipe descriptors
 236     void Close()
 237     {
 238         for ( size_t n = 0; n < WXSIZEOF(m_handles); n++ )
 239         {
 240             if ( m_handles[n] != INVALID_HANDLE_VALUE )
 241             {
 242                 ::CloseHandle(m_handles[n]);
 243                 m_handles[n] = INVALID_HANDLE_VALUE;
 244             }
 245         }
 246     }
 247
 248     // dtor closes the pipe descriptors
 249     ~wxPipe() { Close(); }
 250
 251 private:
 252     HANDLE m_handles[2];
 253 };
 254
 255 #endif // wxUSE_STREAMS
 256
 257 // ============================================================================
 258 // implementation
 259 // ============================================================================
 260
 261 #ifdef __WIN32__
 262
 263 // ----------------------------------------------------------------------------
 264 // process termination detecting support
 265 // ----------------------------------------------------------------------------
 266
 267 // thread function for the thread monitoring the process termination
 268 static DWORD __stdcall wxExecuteThread(void *arg)
 269 {
 270     wxExecuteData * const data = (wxExecuteData *)arg;
 271
 272     if ( ::WaitForSingleObject(data->hProcess, INFINITE) != WAIT_OBJECT_0 )
 273     {
 274         wxLogDebug(_T("Waiting for the process termination failed!"));
 275     }
 276
 277     // get the exit code
 278     if ( !::GetExitCodeProcess(data->hProcess, &data->dwExitCode) )
 279     {
 280         wxLogLastError(wxT("GetExitCodeProcess"));
 281     }
 282
 283     wxASSERT_MSG( data->dwExitCode != STILL_ACTIVE,
 284                   wxT("process should have terminated") );
 285
 286     // send a message indicating process termination to the window
 287     ::SendMessage(data->hWnd, wxWM_PROC_TERMINATED, 0, (LPARAM)data);
 288
 289     return 0;
 290 }
 291
 292 // window procedure of a hidden window which is created just to receive
 293 // the notification message when a process exits
 294 LRESULT APIENTRY _EXPORT wxExecuteWindowCbk(HWND hWnd, UINT message,
 295                                             WPARAM wParam, LPARAM lParam)
 296 {
 297     if ( message == wxWM_PROC_TERMINATED )
 298     {
 299         DestroyWindow(hWnd);    // we don't need it any more
 300
 301         wxExecuteData * const data = (wxExecuteData *)lParam;
 302         if ( data->handler )
 303         {
 304             data->handler->OnTerminate((int)data->dwProcessId,
 305                                        (int)data->dwExitCode);
 306         }
 307
 308         if ( data->state )
 309         {
 310             // we're executing synchronously, tell the waiting thread
 311             // that the process finished
 312             data->state = 0;
 313         }
 314         else
 315         {
 316             // asynchronous execution - we should do the clean up
 317             delete data;
 318         }
 319
 320         return 0;
 321     }
 322     else
 323     {
 324         return ::DefWindowProc(hWnd, message, wParam, lParam);
 325     }
 326 }
 327
 328 // ============================================================================
 329 // implementation of IO redirection support classes
 330 // ============================================================================
 331
 332 #if wxUSE_STREAMS
 333
 334 // ----------------------------------------------------------------------------
 335 // wxPipeInputStreams
 336 // ----------------------------------------------------------------------------
 337
 338 wxPipeInputStream::wxPipeInputStream(HANDLE hInput)
 339 {
 340     m_hInput = hInput;
 341 }
 342
 343 wxPipeInputStream::~wxPipeInputStream()
 344 {
 345     if ( m_hInput != INVALID_HANDLE_VALUE )
 346         ::CloseHandle(m_hInput);
 347 }
 348
 349 bool wxPipeInputStream::CanRead() const
 350 {
 351     if ( !IsOpened() )
 352         return FALSE;
 353
 354     DWORD nAvailable;
 355
 356     // function name is misleading, it works with anon pipes as well
 357     DWORD rc = ::PeekNamedPipe
 358                     (
 359                       m_hInput,     // handle
 360                       NULL, 0,      // ptr to buffer and its size
 361                       NULL,         // [out] bytes read
 362                       &nAvailable,  // [out] bytes available
 363                       NULL          // [out] bytes left
 364                     );
 365
 366     if ( !rc )
 367     {
 368         if ( ::GetLastError() != ERROR_BROKEN_PIPE )
 369         {
 370             // unexpected error
 371             wxLogLastError(_T("PeekNamedPipe"));
 372         }
 373
 374         // don't try to continue reading from a pipe if an error occured or if
 375         // it had been closed
 376         ::CloseHandle(m_hInput);
 377
 378         wxPipeInputStream *self = wxConstCast(this, wxPipeInputStream);
 379
 380         self->m_hInput = INVALID_HANDLE_VALUE;
 381         self->m_lasterror = wxSTREAM_EOF;
 382
 383         nAvailable = 0;
 384     }
 385
 386     return nAvailable != 0;
 387 }
 388
 389 size_t wxPipeInputStream::OnSysRead(void *buffer, size_t len)
 390 {
 391     if ( !IsOpened() )
 392     {
 393         m_lasterror = wxSTREAM_EOF;
 394
 395         return 0;
 396     }
 397
 398     DWORD bytesRead;
 399     if ( !::ReadFile(m_hInput, buffer, len, &bytesRead, NULL) )
 400     {
 401         m_lasterror = ::GetLastError() == ERROR_BROKEN_PIPE
 402                         ? wxSTREAM_EOF
 403                         : wxSTREAM_READ_ERROR;
 404     }
 405
 406     // bytesRead is set to 0, as desired, if an error occured
 407     return bytesRead;
 408 }
 409
 410 // ----------------------------------------------------------------------------
 411 // wxPipeOutputStream
 412 // ----------------------------------------------------------------------------
 413
 414 wxPipeOutputStream::wxPipeOutputStream(HANDLE hOutput)
 415 {
 416     m_hOutput = hOutput;
 417 }
 418
 419 wxPipeOutputStream::~wxPipeOutputStream()
 420 {
 421     ::CloseHandle(m_hOutput);
 422 }
 423
 424 size_t wxPipeOutputStream::OnSysWrite(const void *buffer, size_t len)
 425 {
 426     DWORD bytesWritten;
 427
 428     m_lasterror = wxSTREAM_NO_ERROR;
 429     if ( !::WriteFile(m_hOutput, buffer, len, &bytesWritten, NULL) )
 430     {
 431         m_lasterror = ::GetLastError() == ERROR_BROKEN_PIPE
 432                             ? wxSTREAM_EOF
 433                             : wxSTREAM_WRITE_ERROR;
 434     }
 435
 436     return bytesWritten;
 437 }
 438
 439 #endif // wxUSE_STREAMS
 440
 441 #endif // Win32
 442
 443 // ============================================================================
 444 // wxExecute functions family
 445 // ============================================================================
 446
 447 #if wxUSE_IPC
 448
 449 // connect to the given server via DDE and ask it to execute the command
 450 static bool wxExecuteDDE(const wxString& ddeServer,
 451                          const wxString& ddeTopic,
 452                          const wxString& ddeCommand)
 453 {
 454     bool ok = FALSE;
 455
 456     wxDDEClient client;
 457     wxConnectionBase *conn = client.MakeConnection(_T(""),
 458                                                    ddeServer,
 459                                                    ddeTopic);
 460     if ( !conn )
 461     {
 462         ok = FALSE;
 463     }
 464     else // connected to DDE server
 465     {
 466         // the added complication here is that although most
 467         // programs use XTYP_EXECUTE for their DDE API, some
 468         // important ones - like IE and other MS stuff - use
 469         // XTYP_REQUEST!
 470         //
 471         // so we try one first and then the other one if it
 472         // failed
 473         {
 474             wxLogNull noErrors;
 475             ok = conn->Execute(ddeCommand);
 476         }
 477
 478         if ( !ok )
 479         {
 480             // now try request - but show the errors
 481             ok = conn->Request(ddeCommand) != NULL;
 482         }
 483     }
 484
 485     return ok;
 486 }
 487
 488 #endif // wxUSE_IPC
 489
 490 long wxExecute(const wxString& cmd, int flags, wxProcess *handler)
 491 {
 492     wxCHECK_MSG( !!cmd, 0, wxT("empty command in wxExecute") );
 493
 494 #if wxUSE_THREADS
 495     // for many reasons, the code below breaks down if it's called from another
 496     // thread -- this could be fixed, but as Unix versions don't support this
 497     // neither I don't want to waste time on this now
 498     wxASSERT_MSG( wxThread::IsMain(),
 499                     _T("wxExecute() can be called only from the main thread") );
 500 #endif // wxUSE_THREADS
 501
 502     wxString command;
 503
 504 #if wxUSE_IPC
 505     // DDE hack: this is really not pretty, but we need to allow this for
 506     // transparent handling of DDE servers in wxMimeTypesManager. Usually it
 507     // returns the command which should be run to view/open/... a file of the
 508     // given type. Sometimes, however, this command just launches the server
 509     // and an additional DDE request must be made to really open the file. To
 510     // keep all this well hidden from the application, we allow a special form
 511     // of command: WX_DDE#<command>#DDE_SERVER#DDE_TOPIC#DDE_COMMAND in which
 512     // case we execute just <command> and process the rest below
 513     wxString ddeServer, ddeTopic, ddeCommand;
 514     static const size_t lenDdePrefix = 7;   // strlen("WX_DDE:")
 515     if ( cmd.Left(lenDdePrefix) == _T("WX_DDE#") )
 516     {
 517         // speed up the concatenations below
 518         ddeServer.reserve(256);
 519         ddeTopic.reserve(256);
 520         ddeCommand.reserve(256);
 521
 522         const wxChar *p = cmd.c_str() + 7;
 523         while ( *p && *p != _T('#') )
 524         {
 525             command += *p++;
 526         }
 527
 528         if ( *p )
 529         {
 530             // skip '#'
 531             p++;
 532         }
 533         else
 534         {
 535             wxFAIL_MSG(_T("invalid WX_DDE command in wxExecute"));
 536         }
 537
 538         while ( *p && *p != _T('#') )
 539         {
 540             ddeServer += *p++;
 541         }
 542
 543         if ( *p )
 544         {
 545             // skip '#'
 546             p++;
 547         }
 548         else
 549         {
 550             wxFAIL_MSG(_T("invalid WX_DDE command in wxExecute"));
 551         }
 552
 553         while ( *p && *p != _T('#') )
 554         {
 555             ddeTopic += *p++;
 556         }
 557
 558         if ( *p )
 559         {
 560             // skip '#'
 561             p++;
 562         }
 563         else
 564         {
 565             wxFAIL_MSG(_T("invalid WX_DDE command in wxExecute"));
 566         }
 567
 568         while ( *p )
 569         {
 570             ddeCommand += *p++;
 571         }
 572
 573         // if we want to just launch the program and not wait for its
 574         // termination, try to execute DDE command right now, it can succeed if
 575         // the process is already running - but as it fails if it's not
 576         // running, suppress any errors it might generate
 577         if ( !(flags & wxEXEC_SYNC) )
 578         {
 579             wxLogNull noErrors;
 580             if ( wxExecuteDDE(ddeServer, ddeTopic, ddeCommand) )
 581             {
 582                 // a dummy PID - this is a hack, of course, but it's well worth
 583                 // it as we don't open a new server each time we're called
 584                 // which would be quite bad
 585                 return -1;
 586             }
 587         }
 588     }
 589     else
 590 #endif // wxUSE_IPC
 591     {
 592         // no DDE
 593         command = cmd;
 594     }
 595
 596     // the IO redirection is only supported with wxUSE_STREAMS
 597     BOOL redirect = FALSE;
 598
 599 #if wxUSE_STREAMS
 600     wxPipe pipeIn, pipeOut, pipeErr;
 601
 602     // we'll save here the copy of pipeIn[Write]
 603     HANDLE hpipeStdinWrite = INVALID_HANDLE_VALUE;
 604
 605     // open the pipes to which child process IO will be redirected if needed
 606     if ( handler && handler->IsRedirected() )
 607     {
 608         // create pipes for redirecting stdin, stdout and stderr
 609         if ( !pipeIn.Create() || !pipeOut.Create() || !pipeErr.Create() )
 610         {
 611             wxLogSysError(_("Failed to redirect the child process IO"));
 612
 613             // indicate failure: we need to return different error code
 614             // depending on the sync flag
 615             return flags & wxEXEC_SYNC ? -1 : 0;
 616         }
 617
 618         redirect = TRUE;
 619     }
 620 #endif // wxUSE_STREAMS
 621
 622     // create the process
 623     STARTUPINFO si;
 624     wxZeroMemory(si);
 625     si.cb = sizeof(si);
 626
 627 #if wxUSE_STREAMS
 628     if ( redirect )
 629     {
 630         si.dwFlags = STARTF_USESTDHANDLES;
 631
 632         si.hStdInput = pipeIn[wxPipe::Read];
 633         si.hStdOutput = pipeOut[wxPipe::Write];
 634         si.hStdError = pipeErr[wxPipe::Write];
 635
 636         // when the std IO is redirected, we don't show the (console) process
 637         // window by default, but this can be overridden by the caller by
 638         // specifying wxEXEC_NOHIDE flag
 639         if ( !(flags & wxEXEC_NOHIDE) )
 640         {
 641             si.dwFlags |= STARTF_USESHOWWINDOW;
 642             si.wShowWindow = SW_HIDE;
 643         }
 644
 645         // we must duplicate the handle to the write side of stdin pipe to make
 646         // it non inheritable: indeed, we must close the writing end of pipeIn
 647         // before launching the child process as otherwise this handle will be
 648         // inherited by the child which will never close it and so the pipe
 649         // will never be closed and the child will be left stuck in ReadFile()
 650         HANDLE pipeInWrite = pipeIn.Detach(wxPipe::Write);
 651         if ( !::DuplicateHandle
 652                 (
 653                     ::GetCurrentProcess(),
 654                     pipeInWrite,
 655                     ::GetCurrentProcess(),
 656                     &hpipeStdinWrite,
 657                     0,                      // desired access: unused here
 658                     FALSE,                  // not inherited
 659                     DUPLICATE_SAME_ACCESS   // same access as for src handle
 660                 ) )
 661         {
 662             wxLogLastError(_T("DuplicateHandle"));
 663         }
 664
 665         ::CloseHandle(pipeInWrite);
 666     }
 667 #endif // wxUSE_STREAMS
 668
 669     PROCESS_INFORMATION pi;
 670     DWORD dwFlags = CREATE_DEFAULT_ERROR_MODE | CREATE_SUSPENDED;
 671
 672     bool ok = ::CreateProcess
 673                 (
 674                  NULL,              // application name (use only cmd line)
 675                  (wxChar *)
 676                  command.c_str(),   // full command line
 677                  NULL,              // security attributes: defaults for both
 678                  NULL,              //   the process and its main thread
 679                  redirect,          // inherit handles if we use pipes
 680                  dwFlags,           // process creation flags
 681                  NULL,              // environment (use the same)
 682                  NULL,              // current directory (use the same)
 683                  &si,               // startup info (unused here)
 684                  &pi                // process info
 685                 ) != 0;
 686
 687 #if wxUSE_STREAMS
 688     // we can close the pipe ends used by child anyhow
 689     if ( redirect )
 690     {
 691         ::CloseHandle(pipeIn.Detach(wxPipe::Read));
 692         ::CloseHandle(pipeOut.Detach(wxPipe::Write));
 693         ::CloseHandle(pipeErr.Detach(wxPipe::Write));
 694     }
 695 #endif // wxUSE_STREAMS
 696
 697     if ( !ok )
 698     {
 699 #if wxUSE_STREAMS
 700         // close the other handles too
 701         if ( redirect )
 702         {
 703             ::CloseHandle(pipeOut.Detach(wxPipe::Read));
 704             ::CloseHandle(pipeErr.Detach(wxPipe::Read));
 705         }
 706 #endif // wxUSE_STREAMS
 707
 708         wxLogSysError(_("Execution of command '%s' failed"), command.c_str());
 709
 710         return flags & wxEXEC_SYNC ? -1 : 0;
 711     }
 712
 713 #if wxUSE_STREAMS
 714     // the input buffer bufOut is connected to stdout, this is why it is
 715     // called bufOut and not bufIn
 716     wxStreamTempInputBuffer bufOut,
 717                             bufErr;
 718
 719     if ( redirect )
 720     {
 721         // We can now initialize the wxStreams
 722         wxPipeInputStream *
 723             outStream = new wxPipeInputStream(pipeOut.Detach(wxPipe::Read));
 724         wxPipeInputStream *
 725             errStream = new wxPipeInputStream(pipeErr.Detach(wxPipe::Read));
 726         wxPipeOutputStream *
 727             inStream = new wxPipeOutputStream(hpipeStdinWrite);
 728
 729         handler->SetPipeStreams(outStream, inStream, errStream);
 730
 731         bufOut.Init(outStream);
 732         bufErr.Init(errStream);
 733     }
 734 #endif // wxUSE_STREAMS
 735
 736     // register the class for the hidden window used for the notifications
 737     if ( !gs_classForHiddenWindow )
 738     {
 739         gs_classForHiddenWindow = _T("wxHiddenWindow");
 740
 741         WNDCLASS wndclass;
 742         wxZeroMemory(wndclass);
 743         wndclass.lpfnWndProc   = (WNDPROC)wxExecuteWindowCbk;
 744         wndclass.hInstance     = wxGetInstance();
 745         wndclass.lpszClassName = gs_classForHiddenWindow;
 746
 747         if ( !::RegisterClass(&wndclass) )
 748         {
 749             wxLogLastError(wxT("RegisterClass(hidden window)"));
 750         }
 751     }
 752
 753     // create a hidden window to receive notification about process
 754     // termination
 755     HWND hwnd = ::CreateWindow(gs_classForHiddenWindow, NULL,
 756                                WS_OVERLAPPEDWINDOW,
 757                                0, 0, 0, 0, NULL,
 758                                (HMENU)NULL, wxGetInstance(), 0);
 759     wxASSERT_MSG( hwnd, wxT("can't create a hidden window for wxExecute") );
 760
 761     // Alloc data
 762     wxExecuteData *data = new wxExecuteData;
 763     data->hProcess    = pi.hProcess;
 764     data->dwProcessId = pi.dwProcessId;
 765     data->hWnd        = hwnd;
 766     data->state       = (flags & wxEXEC_SYNC) != 0;
 767     if ( flags & wxEXEC_SYNC )
 768     {
 769         // handler may be !NULL for capturing program output, but we don't use
 770         // it wxExecuteData struct in this case
 771         data->handler = NULL;
 772     }
 773     else
 774     {
 775         // may be NULL or not
 776         data->handler = handler;
 777     }
 778
 779     DWORD tid;
 780     HANDLE hThread = ::CreateThread(NULL,
 781                                     0,
 782                                     wxExecuteThread,
 783                                     (void *)data,
 784                                     0,
 785                                     &tid);
 786
 787     // resume process we created now - whether the thread creation succeeded or
 788     // not
 789     if ( ::ResumeThread(pi.hThread) == (DWORD)-1 )
 790     {
 791         // ignore it - what can we do?
 792         wxLogLastError(wxT("ResumeThread in wxExecute"));
 793     }
 794
 795     // close unneeded handle
 796     if ( !::CloseHandle(pi.hThread) )
 797         wxLogLastError(wxT("CloseHandle(hThread)"));
 798
 799     if ( !hThread )
 800     {
 801         wxLogLastError(wxT("CreateThread in wxExecute"));
 802
 803         DestroyWindow(hwnd);
 804         delete data;
 805
 806         // the process still started up successfully...
 807         return pi.dwProcessId;
 808     }
 809
 810     ::CloseHandle(hThread);
 811
 812 #if wxUSE_IPC
 813     // second part of DDE hack: now establish the DDE conversation with the
 814     // just launched process
 815     if ( !ddeServer.empty() )
 816     {
 817         bool ok;
 818
 819         // give the process the time to init itself
 820         //
 821         // we use a very big timeout hoping that WaitForInputIdle() will return
 822         // much sooner, but not INFINITE just in case the process hangs
 823         // completely - like this we will regain control sooner or later
 824         switch ( ::WaitForInputIdle(pi.hProcess, 10000 /* 10 seconds */) )
 825         {
 826             default:
 827                 wxFAIL_MSG( _T("unexpected WaitForInputIdle() return code") );
 828                 // fall through
 829
 830             case -1:
 831                 wxLogLastError(_T("WaitForInputIdle() in wxExecute"));
 832
 833             case WAIT_TIMEOUT:
 834                 wxLogDebug(_T("Timeout too small in WaitForInputIdle"));
 835
 836                 ok = FALSE;
 837                 break;
 838
 839             case 0:
 840                 // ok, process ready to accept DDE requests
 841                 ok = wxExecuteDDE(ddeServer, ddeTopic, ddeCommand);
 842         }
 843     }
 844 #endif // wxUSE_IPC
 845
 846     if ( !(flags & wxEXEC_SYNC) )
 847     {
 848         // clean up will be done when the process terminates
 849
 850         // return the pid
 851         return pi.dwProcessId;
 852     }
 853
 854     wxAppTraits *traits = wxTheApp ? wxTheApp->GetTraits() : NULL;
 855     wxCHECK_MSG( traits, -1, _T("no wxAppTraits in wxExecute()?") );
 856
 857     // disable all app windows while waiting for the child process to finish
 858     void *cookie = traits->BeforeChildWaitLoop();
 859
 860     // wait until the child process terminates
 861     while ( data->state )
 862     {
 863 #if wxUSE_STREAMS
 864         bufOut.Update();
 865         bufErr.Update();
 866 #endif // wxUSE_STREAMS
 867
 868         // don't eat 100% of the CPU -- ugly but anything else requires
 869         // real async IO which we don't have for the moment
 870         ::Sleep(50);
 871
 872         // we must process messages or we'd never get wxWM_PROC_TERMINATED
 873         traits->AlwaysYield();
 874     }
 875
 876     traits->AfterChildWaitLoop(cookie);
 877
 878     DWORD dwExitCode = data->dwExitCode;
 879     delete data;
 880
 881     // return the exit code
 882     return dwExitCode;
 883 }
 884
 885 long wxExecute(wxChar **argv, int flags, wxProcess *handler)
 886 {
 887     wxString command;
 888
 889     for ( ;; )
 890     {
 891         command += *argv++;
 892         if ( !*argv )
 893             break;
 894
 895         command += _T(' ');
 896     }
 897
 898     return wxExecute(command, flags, handler);
 899 }
 900