include/wvqtstreamclone.h

   1 /* -*- Mode: C++ -*-
   2  * Worldvisions Weaver Software:
   3  *   Copyright (C) 1997-2002 Net Integration Technologies, Inc.
   4  *
   5  */
   6 #ifndef __WVQTSTREAMCLONE_H
   7 #define __WVQTSTREAMCLONE_H
   8
   9 #include <qobject.h>
  10 #include <qintdict.h>
  11 #include <qsocketnotifier.h>
  12 #include <qtimer.h>
  13 #include <qmetaobject.h>
  14 #include "wvstreamclone.h"
  15
  16 /**
  17  * Wraps another WvStream and attaches it to the normal Qt event loop.
  18  *
  19  * If you are using this object exclusively to manage all of your
  20  * streams, then you do not need to have a normal WvStreams
  21  * select()/callback() loop in your application at all.
  22  *
  23  * However, should you leave the Qt event loop and wish to continue
  24  * using this WvStream, call qt_detach() first, then run a normal
  25  * WvStreams event loop.  If you do not do this, events may be
  26  * lost!  Later, you may resume the Qt event loop at any time
  27  * by leaving your WvStreams event loop and calling qt_attach().
  28  *
  29  * Multiple instances of this object may coexist to wrap different
  30  * WvStream's or WvStreamList's.
  31  *
  32  */
  33 class WvQtStreamClone : public QObject, public WvStreamClone
  34 {
  35     Q_OBJECT
  36     int msec_timeout;
  37
  38     SelectInfo si;
  39     bool pending_callback;
  40     bool first_time;
  41     bool select_in_progress;
  42     int last_max_fd;
  43     QIntDict<QSocketNotifier> notify_readable;
  44     QIntDict<QSocketNotifier> notify_writable;
  45     QIntDict<QSocketNotifier> notify_exception;
  46     QTimer select_timer;
  47
  48 public:
  49     /**
  50      * WvQtStreamClone takes ownership of the stream you give it
  51      * just like WvStreamClone.  See comments there.
  52      *
  53      * Timeout sets the time between polls with select().
  54      * A value less than zero is regarded as an infinite timeout.
  55      */
  56     WvQtStreamClone(IWvStream *_cloned = NULL, int msec_timeout = -1);
  57     virtual ~WvQtStreamClone();
  58
  59     // Call this to stop managing this stream via the Qt event loop.
  60     // Afterwards you may run a normal WvStream event loop based
  61     // on this object.
  62     void qt_detach();
  63
  64     // Call this to resume managing this stream via the Qt event loop.
  65     // This is the default state when the object is constructed.
  66     void qt_attach();
  67
  68     // Changes the timeout
  69     // You may need to adjust the timeout when using badly behaved streams
  70     void set_timeout(int msec_timeout);
  71
  72 private:
  73     // Called before the Qt event loop does its select()
  74     void pre_poll();
  75     // Called after the Qt event loop has finished its notifications
  76     void post_poll();
  77
  78 private slots:
  79     /** These things mark the beginning of a select pass **/
  80     // Qt event loop hook (happens before each iteration)
  81     void qt_begin_event_loop_hook();
  82
  83     /** These things mark the end of a select pass **/
  84     // Qt select timeout expired
  85     void select_timer_expired();
  86     // Called when a file descriptor has been marked readable
  87     void fd_readable(int fd);
  88     // Called when a file descriptor has been marked writable
  89     void fd_writable(int fd);
  90     // Called when a file descriptor has been marked with an exception
  91     void fd_exception(int fd);
  92
  93     // Needed or certain assertions fail ;)
  94     virtual void execute();
  95
  96 public:
  97     virtual void setclone(IWvStream *clone);
  98 };
  99
 100 #endif // __WVQTSTREAMCLONE_H