common code for normalization

[wxWidgets.git] / src / unix / evtloopunix.cpp

diff --git a/src/unix/evtloopunix.cpp b/src/unix/evtloopunix.cpp
index b082984019b700bf980ce856672b7defb442d972..a4f67ecad633248127db883e71f257f4a511ad50 100644 (file)
--- a/src/unix/evtloopunix.cpp
+++ b/src/unix/evtloopunix.cpp
@@ -30,6 +30,7 @@
 
 #include <errno.h>
 #include "wx/apptrait.h"
 
 #include <errno.h>
 #include "wx/apptrait.h"

+#include "wx/scopedptr.h"

 #include "wx/thread.h"
 #include "wx/module.h"
 #include "wx/unix/pipe.h"
 #include "wx/thread.h"
 #include "wx/module.h"
 #include "wx/unix/pipe.h"


@@ -37,6 +38,10 @@
 #include "wx/unix/private/epolldispatcher.h"
 #include "wx/private/selectdispatcher.h"
 
 #include "wx/unix/private/epolldispatcher.h"
 #include "wx/private/selectdispatcher.h"
 

+#if wxUSE_EVENTLOOP_SOURCE
+    #include "wx/evtloopsrc.h"
+#endif // wxUSE_EVENTLOOP_SOURCE
+

 #define TRACE_EVENTS wxT("events")
 
 // ===========================================================================
 #define TRACE_EVENTS wxT("events")
 
 // ===========================================================================


@@ -53,7 +58,7 @@ class PipeIOHandler : public wxFDIOHandler
 public:
     // default ctor does nothing, call Create() to really initialize the
     // object
 public:
     // default ctor does nothing, call Create() to really initialize the
     // object

-    PipeIOHandler() { }
+    PipeIOHandler() : m_pipeIsEmpty(true) { }

 
     bool Create();
 
 
     bool Create();
 


@@ -69,6 +74,15 @@ public:
 
 private:
     wxPipe m_pipe;
 
 private:
     wxPipe m_pipe;

+
+    // Protects access to m_pipeIsEmpty.
+    wxCriticalSection m_pipeLock;
+
+    // This flag is set to true after writing to the pipe and reset to false
+    // after reading from it in the main thread. Having it allows us to avoid
+    // overflowing the pipe with too many writes if the main thread can't keep
+    // up with reading from it.
+    bool m_pipeIsEmpty;

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -83,17 +97,15 @@ bool PipeIOHandler::Create()
         return false;
     }
 
         return false;
     }
 

-    const int fdRead = GetReadFd();

 
 

-    int flags = fcntl(fdRead, F_GETFL, 0);
-    if ( flags == -1 || fcntl(fdRead, F_SETFL, flags | O_NONBLOCK) == -1 )
+    if ( !m_pipe.MakeNonBlocking(wxPipe::Read) )

     {
         wxLogSysError(_("Failed to switch wake up pipe to non-blocking mode"));
         return false;
     }
 
     wxLogTrace(TRACE_EVENTS, wxT("Wake up pipe (%d, %d) created"),
     {
         wxLogSysError(_("Failed to switch wake up pipe to non-blocking mode"));
         return false;
     }
 
     wxLogTrace(TRACE_EVENTS, wxT("Wake up pipe (%d, %d) created"),

-               fdRead, m_pipe[wxPipe::Write]);
+               m_pipe[wxPipe::Read], m_pipe[wxPipe::Write]);

 
     return true;
 }
 
     return true;
 }


@@ -104,39 +116,66 @@ bool PipeIOHandler::Create()
 
 void PipeIOHandler::WakeUp()
 {
 
 void PipeIOHandler::WakeUp()
 {

+    wxCriticalSectionLocker lock(m_pipeLock);
+
+    // No need to do anything if the pipe already contains something.
+    if ( !m_pipeIsEmpty )
+      return;
+

     if ( write(m_pipe[wxPipe::Write], "s", 1) != 1 )
     {
         // don't use wxLog here, we can be in another thread and this could
         // result in dead locks
         perror("write(wake up pipe)");
     }
     if ( write(m_pipe[wxPipe::Write], "s", 1) != 1 )
     {
         // don't use wxLog here, we can be in another thread and this could
         // result in dead locks
         perror("write(wake up pipe)");
     }

+    else
+    {
+        // We just wrote to it, so it's not empty any more.
+        m_pipeIsEmpty = false;
+    }

 }
 
 void PipeIOHandler::OnReadWaiting()
 {
 }
 
 void PipeIOHandler::OnReadWaiting()
 {

-    // got wakeup from child thread: read all data available in pipe just to
-    // make it empty (even though we write one byte at a time from WakeUp(),
-    // it could have been called several times)
+    // got wakeup from child thread, remove the data that provoked it from the
+    // pipe
+
+    wxCriticalSectionLocker lock(m_pipeLock);
+

     char buf[4];
     for ( ;; )
     {
         const int size = read(GetReadFd(), buf, WXSIZEOF(buf));
 
     char buf[4];
     for ( ;; )
     {
         const int size = read(GetReadFd(), buf, WXSIZEOF(buf));
 

-        if ( size == 0 || (size == -1 && (errno == EAGAIN || errno == EINTR)) )
+        if ( size > 0 )

         {
         {

-            // nothing left in the pipe (EAGAIN is expected for an FD with
-            // O_NONBLOCK)
+            wxASSERT_MSG( size == 1, "Too many writes to wake-up pipe?" );
+

             break;
         }
 
             break;
         }
 

-        if ( size == -1 )
+        if ( size == 0 || (size == -1 && errno == EAGAIN) )

         {
         {

-            wxLogSysError(_("Failed to read from wake-up pipe"));
-
+            // No data available, not an error (but still surprising,
+            // spurious wakeup?)

             break;
         }
             break;
         }

+
+        if ( errno == EINTR )
+        {
+            // We were interrupted, try again.
+            continue;
+        }
+
+        wxLogSysError(_("Failed to read from wake-up pipe"));
+
+        return;

     }
 
     }
 

+    // The pipe is empty now, so future calls to WakeUp() would need to write
+    // to it again.
+    m_pipeIsEmpty = true;
+

     // writing to the wake up pipe will make wxConsoleEventLoop return from
     // wxFDIODispatcher::Dispatch() it might be currently blocking in, nothing
     // else needs to be done
     // writing to the wake up pipe will make wxConsoleEventLoop return from
     // wxFDIODispatcher::Dispatch() it might be currently blocking in, nothing
     // else needs to be done


@@ -220,36 +259,40 @@ protected:
     wxEventLoopSourceHandler* m_impl;
 };
 
     wxEventLoopSourceHandler* m_impl;
 };
 

-bool wxConsoleEventLoop::DoAddSource(wxAbstractEventLoopSource* src)
+wxEventLoopSource *
+wxConsoleEventLoop::AddSourceForFD(int fd,
+                                   wxEventLoopSourceHandler *handler,
+                                   int flags)

 {
 {

-    Source* source = dynamic_cast<Source*>(src);
-    wxCHECK_MSG( source, false, "Invalid source type" );
+    wxCHECK_MSG( fd != -1, NULL, "can't monitor invalid fd" );

 
     wxLogTrace(wxTRACE_EVT_SOURCE,
 
     wxLogTrace(wxTRACE_EVT_SOURCE,

-                "wxConsoleEventLoop::AddSource() source=%d",
-                source->GetResource());
+                "Adding event loop source for fd=%d", fd);
+
+    // we need a bridge to wxFDIODispatcher
+    //
+    // TODO: refactor the code so that only wxEventLoopSourceHandler is used
+    wxScopedPtr<wxFDIOHandler>
+        fdioHandler(new wxFDIOEventLoopSourceHandler(handler));

 
 

-    // translating into wxFDIOHandler
-    // XXX this is a memory leak of course, but this is really temporary, so
-    // we are not creating another map of handlers
-    wxFDIOHandler* h = new wxFDIOEventLoopSourceHandler(source->GetHandler());
+    if ( !m_dispatcher->RegisterFD(fd, fdioHandler.get(), flags) )
+        return NULL;

 
 

-    return m_dispatcher->RegisterFD(source->GetResource(), h,
-                                    source->GetFlags());
+    return new wxUnixEventLoopSource(m_dispatcher, fdioHandler.release(),
+                                     fd, handler, flags);

 }
 
 }
 

-bool wxConsoleEventLoop::DoRemoveSource(wxAbstractEventLoopSource* src)
+wxUnixEventLoopSource::~wxUnixEventLoopSource()

 {
 {

-    Source* source = dynamic_cast<Source*>(src);
-    wxCHECK_MSG( source, false, "Invalid source type" );
-

     wxLogTrace(wxTRACE_EVT_SOURCE,
     wxLogTrace(wxTRACE_EVT_SOURCE,

-               "wxConsoleEventLoop::RemoveSource() source=%d",
-               source->GetResource());
+               "Removing event loop source for fd=%d", m_fd);

 
 

-    return m_dispatcher->UnregisterFD(source->GetResource());
+    m_dispatcher->UnregisterFD(m_fd);
+
+    delete m_fdioHandler;

 }
 }

-#endif
+
+#endif // wxUSE_EVENTLOOP_SOURCE

 
 //-----------------------------------------------------------------------------
 // events dispatch and loop handling
 
 //-----------------------------------------------------------------------------
 // events dispatch and loop handling