src/x11/evtloop.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        x11/evtloop.cpp
   3 // Purpose:     implements wxEventLoop for X11
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     01.06.01
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2002 Julian Smart
   9 // License:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "evtloop.h"
  22 #endif
  23
  24 #include "wx/window.h"
  25 #include "wx/app.h"
  26 #include "wx/evtloop.h"
  27 #include "wx/tooltip.h"
  28 #if wxUSE_THREADS
  29 #include "wx/thread.h"
  30 #endif
  31 #include "wx/timer.h"
  32 #include "wx/x11/private.h"
  33 #include "X11/Xlib.h"
  34
  35 #include <sys/time.h>
  36 #include <unistd.h>
  37
  38 // ----------------------------------------------------------------------------
  39 // wxEventLoopImpl
  40 // ----------------------------------------------------------------------------
  41
  42 class WXDLLEXPORT wxEventLoopImpl
  43 {
  44 public:
  45     // ctor
  46     wxEventLoopImpl() { SetExitCode(0); m_keepGoing = FALSE; }
  47
  48     // process an XEvent, return TRUE if it was processed
  49     bool ProcessEvent(XEvent* event);
  50
  51     // generate an idle message, return TRUE if more idle time requested
  52     bool SendIdleEvent();
  53
  54     // set/get the exit code
  55     void SetExitCode(int exitcode) { m_exitcode = exitcode; }
  56     int GetExitCode() const { return m_exitcode; }
  57
  58 public:
  59     // preprocess an event, return TRUE if processed (i.e. no further
  60     // dispatching required)
  61     bool PreProcessEvent(XEvent* event);
  62
  63     // the exit code of the event loop
  64     int m_exitcode;
  65
  66     bool m_keepGoing;
  67 };
  68
  69 // ============================================================================
  70 // wxEventLoopImpl implementation
  71 // ============================================================================
  72
  73 // ----------------------------------------------------------------------------
  74 // wxEventLoopImpl message processing
  75 // ----------------------------------------------------------------------------
  76
  77 bool wxEventLoopImpl::ProcessEvent(XEvent *event)
  78 {
  79     // give us the chance to preprocess the message first
  80     if ( PreProcessEvent(event) )
  81         return TRUE;
  82
  83     // if it wasn't done, dispatch it to the corresponding window
  84     if (wxTheApp)
  85         return wxTheApp->ProcessXEvent((WXEvent*) event);
  86
  87     return FALSE;
  88 }
  89
  90 bool wxEventLoopImpl::PreProcessEvent(XEvent *event)
  91 {
  92     // TODO
  93 #if 0
  94     HWND hWnd = msg->hwnd;
  95     wxWindow *wndThis = wxGetWindowFromHWND((WXHWND)hWnd);
  96
  97
  98     // try translations first; find the youngest window with a translation
  99     // table.
 100     wxWindow *wnd;
 101     for ( wnd = wndThis; wnd; wnd = wnd->GetParent() )
 102     {
 103         if ( wnd->MSWTranslateMessage((WXMSG *)msg) )
 104             return TRUE;
 105     }
 106
 107     // Anyone for a non-translation message? Try youngest descendants first.
 108     for ( wnd = wndThis; wnd; wnd = wnd->GetParent() )
 109     {
 110         if ( wnd->MSWProcessMessage((WXMSG *)msg) )
 111             return TRUE;
 112     }
 113 #endif
 114
 115     return FALSE;
 116 }
 117
 118 // ----------------------------------------------------------------------------
 119 // wxEventLoopImpl idle event processing
 120 // ----------------------------------------------------------------------------
 121
 122 bool wxEventLoopImpl::SendIdleEvent()
 123 {
 124     wxIdleEvent event;
 125     event.SetEventObject(wxTheApp);
 126
 127     return wxTheApp->ProcessEvent(event) && event.MoreRequested();
 128 }
 129
 130 // ============================================================================
 131 // wxEventLoop implementation
 132 // ============================================================================
 133
 134 wxEventLoop *wxEventLoop::ms_activeLoop = NULL;
 135
 136 // ----------------------------------------------------------------------------
 137 // wxEventLoop running and exiting
 138 // ----------------------------------------------------------------------------
 139
 140 wxEventLoop::~wxEventLoop()
 141 {
 142     wxASSERT_MSG( !m_impl, _T("should have been deleted in Run()") );
 143 }
 144
 145 bool wxEventLoop::IsRunning() const
 146 {
 147     return m_impl != NULL;
 148 }
 149
 150 int wxEventLoop::Run()
 151 {
 152     // event loops are not recursive, you need to create another loop!
 153     wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
 154
 155     m_impl = new wxEventLoopImpl;
 156
 157     wxEventLoop *oldLoop = ms_activeLoop;
 158     ms_activeLoop = this;
 159
 160     m_impl->m_keepGoing = TRUE;
 161     while ( m_impl->m_keepGoing )
 162     {
 163 #if 0 // wxUSE_THREADS
 164         wxMutexGuiLeaveOrEnter();
 165 #endif // wxUSE_THREADS
 166
 167         // generate and process idle events for as long as we don't have
 168         // anything else to do
 169         while ( ! Pending() )
 170         {
 171 #if wxUSE_TIMER
 172             wxTimer::NotifyTimers(); // TODO: is this the correct place for it?
 173 #endif
 174             if (!m_impl->SendIdleEvent())
 175             {
 176 #if wxUSE_THREADS
 177                 // leave the main loop to give other threads a chance to
 178                 // perform their GUI work
 179                 wxMutexGuiLeave();
 180                 wxUsleep(20);
 181                 wxMutexGuiEnter();
 182 #endif
 183                 // Break out of while loop
 184                 break;
 185             }
 186         }
 187
 188         // a message came or no more idle processing to do, sit in Dispatch()
 189         // waiting for the next message
 190         if ( !Dispatch() )
 191         {
 192             break;
 193         }
 194     }
 195
 196     int exitcode = m_impl->GetExitCode();
 197     delete m_impl;
 198     m_impl = NULL;
 199
 200     ms_activeLoop = oldLoop;
 201
 202     return exitcode;
 203 }
 204
 205 void wxEventLoop::Exit(int rc)
 206 {
 207     wxCHECK_RET( IsRunning(), _T("can't call Exit() if not running") );
 208
 209     m_impl->SetExitCode(rc);
 210     m_impl->m_keepGoing = FALSE;
 211 }
 212
 213 // ----------------------------------------------------------------------------
 214 // wxEventLoop message processing dispatching
 215 // ----------------------------------------------------------------------------
 216
 217 bool wxEventLoop::Pending() const
 218 {
 219     XFlush((Display*) wxGetDisplay());
 220     return (XPending((Display*) wxGetDisplay()) > 0);
 221 }
 222
 223 bool wxEventLoop::Dispatch()
 224 {
 225     XEvent event;
 226
 227     // TODO allowing for threads, as per e.g. wxMSW
 228
 229 #if 0
 230     XNextEvent((Display*) wxGetDisplay(), & event);
 231 #endif
 232
 233     // This now waits until either an X event is received,
 234     // or the select times out. So we should now process
 235     // wxTimers in a reasonably timely fashion. However it
 236     // does also mean that idle processing will happen more
 237     // often, so we should probably limit idle processing to
 238     // not be repeated more than every N milliseconds.
 239
 240     if (XPending((Display*) wxGetDisplay()) == 0)
 241     {
 242         struct timeval tv;
 243         tv.tv_sec=0;
 244         tv.tv_usec=10000; // TODO make this configurable
 245         int fd = ConnectionNumber((Display*) wxGetDisplay());
 246         fd_set readset;
 247         FD_ZERO(&readset);
 248         FD_SET(fd, &readset);
 249         if (select(fd+1, &readset, NULL, NULL, & tv) == 0)
 250         {
 251             // Timed out, so no event to process
 252             return TRUE;
 253         }
 254         else
 255         {
 256             // An event was pending, so get it
 257             XNextEvent((Display*) wxGetDisplay(), & event);
 258         }
 259     } else
 260     {
 261        XNextEvent((Display*) wxGetDisplay(), & event);
 262     }
 263
 264     (void) m_impl->ProcessEvent(& event);
 265     return TRUE;
 266 }
 267