include/wx/private/fdiodispatcher.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/private/fdiodispatcher.h
   3 // Purpose:     classes for dispatching IO notifications for file descriptors
   4 // Authors:     Lukasz Michalski
   5 // Created:     December 2006
   6 // Copyright:   (c) Lukasz Michalski
   7 // RCS-ID:      $Id$
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_PRIVATE_FDIODISPATCHER_H_
  12 #define _WX_PRIVATE_FDIODISPATCHER_H_
  13
  14 #include "wx/hashmap.h"
  15 #include "wx/private/fdiohandler.h"
  16
  17 // those flags describes sets where descriptor should be added
  18 enum wxFDIODispatcherEntryFlags
  19 {
  20     wxFDIO_INPUT = 1,
  21     wxFDIO_OUTPUT = 2,
  22     wxFDIO_EXCEPTION = 4,
  23     wxFDIO_ALL = wxFDIO_INPUT | wxFDIO_OUTPUT | wxFDIO_EXCEPTION
  24 };
  25
  26 // base class for wxSelectDispatcher and wxEpollDispatcher
  27 class WXDLLIMPEXP_BASE wxFDIODispatcher
  28 {
  29 public:
  30     enum { TIMEOUT_INFINITE = -1 };
  31
  32     // return the global dispatcher to be used for IO events, can be NULL only
  33     // if wxSelectDispatcher wasn't compiled into the library at all as
  34     // creating it never fails
  35     //
  36     // don't delete the returned pointer
  37     static wxFDIODispatcher *Get();
  38
  39     // if we have any registered handlers, check for any pending events to them
  40     // and dispatch them -- this is used from wxX11 and wxDFB event loops
  41     // implementation
  42     static void DispatchPending();
  43
  44     // register handler for the given descriptor with the dispatcher, return
  45     // true on success or false on error
  46     virtual bool RegisterFD(int fd, wxFDIOHandler *handler, int flags) = 0;
  47
  48     // modify descriptor flags or handler, return true on success
  49     virtual bool ModifyFD(int fd, wxFDIOHandler *handler, int flags) = 0;
  50
  51     // unregister descriptor previously registered with RegisterFD()
  52     virtual bool UnregisterFD(int fd) = 0;
  53
  54     // check if any events are currently available without dispatching them
  55     virtual bool HasPending() const = 0;
  56
  57     // wait for an event for at most timeout milliseconds and process it;
  58     // return the number of events processed (possibly 0 if timeout expired) or
  59     // -1 if an error occurred
  60     virtual int Dispatch(int timeout = TIMEOUT_INFINITE) = 0;
  61
  62     virtual ~wxFDIODispatcher() { }
  63 };
  64
  65 //entry for wxFDIOHandlerMap
  66 struct wxFDIOHandlerEntry
  67 {
  68     wxFDIOHandlerEntry()
  69     {
  70     }
  71
  72     wxFDIOHandlerEntry(wxFDIOHandler *handler_, int flags_)
  73         : handler(handler_),
  74           flags(flags_)
  75     {
  76     }
  77
  78     wxFDIOHandler *handler;
  79     int flags;
  80 };
  81
  82 // this hash is used to map file descriptors to their handlers
  83 WX_DECLARE_HASH_MAP(
  84   int,
  85   wxFDIOHandlerEntry,
  86   wxIntegerHash,
  87   wxIntegerEqual,
  88   wxFDIOHandlerMap
  89 );
  90
  91 // FDIODispatcher that holds map fd <-> FDIOHandler, this should be used if
  92 // this map isn't maintained elsewhere already as it is usually needed anyhow
  93 //
  94 // notice that all functions for FD management have implementation
  95 // in the base class and should be called from the derived classes
  96 class WXDLLIMPEXP_BASE wxMappedFDIODispatcher : public wxFDIODispatcher
  97 {
  98 public:
  99     // find the handler for the given fd, return NULL if none
 100     wxFDIOHandler *FindHandler(int fd) const;
 101
 102     // register handler for the given descriptor with the dispatcher, return
 103     // true on success or false on error
 104     virtual bool RegisterFD(int fd, wxFDIOHandler *handler, int flags);
 105
 106     // modify descriptor flags or handler, return true on success
 107     virtual bool ModifyFD(int fd, wxFDIOHandler *handler, int flags);
 108
 109     // unregister descriptor previously registered with RegisterFD()
 110     virtual bool UnregisterFD(int fd);
 111
 112     virtual ~wxMappedFDIODispatcher() { }
 113
 114 protected:
 115     // the fd -> handler map containing all the registered handlers
 116     wxFDIOHandlerMap m_handlers;
 117 };
 118
 119 #endif // _WX_PRIVATE_FDIODISPATCHER_H_