File indexing completed on 2024-05-05 17:50:04

 /*
    Copyright (C) 2013 Andreas Hartmetz <ahartmetz@gmail.com>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LGPL.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
 
    Alternatively, this file is available under the Mozilla Public License
    Version 1.1.  You may obtain a copy of the License at
    http://www.mozilla.org/MPL/
 */
 
 #ifndef IIOEVENTLISTENER_H
 #define IIOEVENTLISTENER_H
 
 #include "platform.h"
 #include "types.h"
 #include "iovaluetypes.h"
 
 class IIoEventSource;
 
 class IIoEventListener
 {
 public:
     virtual ~IIoEventListener();
 
     // Contract: from the first to the last call from this class to IIoEventSource, the FileDescriptor
     // may not change. Notably, when closing, which involves resetting the file descriptor, the listener must
     // remove itself frome the IIoEventSource BEFORE resetting (or closing) the file descriptor.
     // (If the listener closed the fd but did not reset its value - i.e. what FileDescriptor() returns - ,
     // another part of the program could get the same numeric fd value, leading to clashes. So just
     // unregister before actually closing the fd.)
 
     IIoEventSource *ioEventSource() const;
     uint32 ioInterest() const;
     virtual IO::Status handleIoReady(IO::RW rw) = 0;
     virtual FileDescriptor fileDescriptor() const = 0;
 
 protected:
     void setIoInterest(uint32 ioRw);
 
 private:
     friend class IIoEventSource;
     IIoEventSource *m_eventSource = nullptr; // set by IIoEventSource, read by this class
     uint32 m_ioInterest = 0; // set by this class, read by IIoEventSource
 };
 
 #endif // IIOEVENTLISTENER_H