implement event loop for console applications (heavily modified patch 1715735)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@46029 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/unix/epolldispatcher.cpp

@@ -0,0 +1,219 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        src/common/epolldispatcher.cpp
+// Purpose:     implements dispatcher for epoll_wait() call
+// Author:      Lukasz Michalski
+// Created:     April 2007
+// RCS-ID:      $Id$
+// Copyright:   (c) 2007 Lukasz Michalski
+// License:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+// ============================================================================
+// declarations
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+// for compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef HAVE_SYS_EPOLL_H
+
+#include "wx/unix/private/epolldispatcher.h"
+#include "wx/unix/private.h"
+#include "wx/log.h"
+#include "wx/module.h"
+
+#include <sys/epoll.h>
+#include <errno.h>
+
+#define wxEpollDispatcher_Trace wxT("epolldispatcher")
+
+static wxEpollDispatcher *gs_epollDispatcher = NULL;
+
+// ============================================================================
+// implementation
+// ============================================================================
+
+// helper: return EPOLLxxx mask corresponding to the given flags (and also log
+// debugging messages about it)
+static uint32_t GetEpollMask(int flags, int fd)
+{
+    uint32_t ep = 0;
+
+    if ( flags & wxFDIO_INPUT )
+    {
+        ep |= EPOLLIN;
+        wxLogTrace(wxEpollDispatcher_Trace,
+                   _T("Registered fd %d for input events"), fd);
+    }
+
+    if ( flags & wxFDIO_OUTPUT )
+    {
+        ep |= EPOLLOUT;
+        wxLogTrace(wxEpollDispatcher_Trace,
+                   _T("Registered fd %d for output events"), fd);
+    }
+
+    if ( flags & wxFDIO_EXCEPTION )
+    {
+        ep |= EPOLLERR | EPOLLHUP;
+        wxLogTrace(wxEpollDispatcher_Trace,
+                   _T("Registered fd %d for exceptional events"), fd);
+    }
+
+    return ep;
+}
+
+// ----------------------------------------------------------------------------
+// wxEpollDispatcher
+// ----------------------------------------------------------------------------
+
+wxEpollDispatcher::wxEpollDispatcher()
+{
+    m_epollDescriptor = epoll_create(1024);
+    if ( m_epollDescriptor == -1 )
+    {
+        wxLogSysError(_("Failed to create epoll descriptor"));
+    }
+}
+
+bool wxEpollDispatcher::RegisterFD(int fd, wxFDIOHandler* handler, int flags)
+{
+    if ( !wxFDIODispatcher::RegisterFD(fd, handler, flags) )
+        return false;
+
+    epoll_event ev;
+    ev.events = GetEpollMask(flags, fd);
+    ev.data.ptr = handler;
+
+    const int ret = epoll_ctl(m_epollDescriptor, EPOLL_CTL_ADD, fd, &ev);
+    if ( ret != 0 )
+    {
+        wxLogSysError(_("Failed to add descriptor %d to epoll descriptor %d"),
+                      fd, m_epollDescriptor);
+
+        return false;
+    }
+
+    return true;
+}
+
+bool wxEpollDispatcher::ModifyFD(int fd, wxFDIOHandler* handler, int flags)
+{
+    if ( !wxFDIODispatcher::ModifyFD(fd, handler, flags) )
+        return false;
+
+    epoll_event ev;
+    ev.events = GetEpollMask(flags, fd);
+    ev.data.ptr = handler;
+
+    const int ret = epoll_ctl(m_epollDescriptor, EPOLL_CTL_MOD, fd, &ev);
+    if ( ret != 0 )
+    {
+        wxLogSysError(_("Failed to modify descriptor %d in epoll descriptor %d"),
+                      fd, m_epollDescriptor);
+
+        return false;
+    }
+
+    return true;
+}
+
+wxFDIOHandler *wxEpollDispatcher::UnregisterFD(int fd, int flags)
+{
+    wxFDIOHandler * const handler = wxFDIODispatcher::UnregisterFD(fd, flags);
+    if ( !handler )
+        return NULL;
+
+    epoll_event ev;
+    ev.events = 0;
+    ev.data.ptr = NULL;
+
+    if ( epoll_ctl(m_epollDescriptor, EPOLL_CTL_DEL, fd, &ev) != 0 )
+    {
+        wxLogSysError(_("Failed to unregister descriptor %d from epoll descriptor %d"),
+                      fd, m_epollDescriptor);
+    }
+
+    return handler;
+}
+
+void wxEpollDispatcher::RunLoop(int timeout)
+{
+    epoll_event events[16];
+
+    const int e_num = epoll_wait
+                      (
+                        m_epollDescriptor,
+                        events,
+                        WXSIZEOF(events),
+                        timeout == TIMEOUT_INFINITE ? -1 : timeout
+                      );
+
+    if ( e_num == -1 )
+    {
+        if ( errno != EINTR )
+        {
+            wxLogSysError(_("Waiting for IO on epoll descriptor %d failed"),
+                          m_epollDescriptor);
+            return;
+        }
+    }
+
+    for ( epoll_event *p = events; p < events + e_num; p++ )
+    {
+        wxFDIOHandler * const handler = (wxFDIOHandler *)(p->data.ptr);
+        if ( !handler )
+        {
+            wxFAIL_MSG( _T("NULL handler in epoll_event?") );
+            continue;
+        }
+
+        if ( p->events & EPOLLIN )
+            handler->OnReadWaiting();
+
+        if ( p->events & EPOLLOUT )
+            handler->OnWriteWaiting();
+
+        if ( p->events & (EPOLLERR | EPOLLHUP) )
+            handler->OnExceptionWaiting();
+    }
+}
+
+/* static */
+wxEpollDispatcher *wxEpollDispatcher::Get()
+{
+    if ( !gs_epollDispatcher )
+    {
+        gs_epollDispatcher = new wxEpollDispatcher;
+        if ( !gs_epollDispatcher->IsOk() )
+        {
+            delete gs_epollDispatcher;
+            gs_epollDispatcher = NULL;
+        }
+    }
+
+    return gs_epollDispatcher;
+}
+
+// ----------------------------------------------------------------------------
+// wxEpollDispatcherModule
+// ----------------------------------------------------------------------------
+
+class wxEpollDispatcherModule : public wxModule
+{
+public:
+    wxEpollDispatcherModule() { }
+
+    virtual bool OnInit() { return true; }
+    virtual void OnExit() { wxDELETE(gs_epollDispatcher); }
+
+    DECLARE_DYNAMIC_CLASS(wxEpollDispatcherModule)
+};
+
+IMPLEMENT_DYNAMIC_CLASS(wxEpollDispatcherModule, wxModule)
+
+#endif // HAVE_SYS_EPOLL_H