1 /* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
2  * Copyright 2009-2019 Pierre Ossman for Cendio AB
3  *
4  * This is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This software is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this software; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
17  * USA.
18  */
19 
20 /////////////////////////////////////////////////////////////////////////////
21 
22 // SDesktop is an interface implemented by back-ends, on which callbacks are
23 // made by the VNCServer as appropriate for pointer and keyboard events, etc.
24 // SDesktop objects are always created before the VNCServer - the SDesktop
25 // will be passed a pointer to the VNCServer in the start() call.  If a more
26 // implementation-specific pointer to the VNCServer is required then this
27 // can be provided to the SDesktop via an implementation-specific method.
28 //
29 // An SDesktop usually has an associated PixelBuffer which it tells the
30 // VNCServer via the VNCServer's setPixelBuffer() method.  It can do this at
31 // any time, but the PixelBuffer MUST be valid by the time the call to start()
32 // returns.  The PixelBuffer may be set to null again if desired when stop() is
33 // called.  Note that start() and stop() are guaranteed to be called
34 // alternately; there should never be two calls to start() without an
35 // intervening stop() and vice-versa.
36 //
37 
38 #ifndef __RFB_SDESKTOP_H__
39 #define __RFB_SDESKTOP_H__
40 
41 #include <rfb/PixelBuffer.h>
42 #include <rfb/VNCServer.h>
43 #include <rfb/InputHandler.h>
44 #include <rfb/Exception.h>
45 #include <rfb/screenTypes.h>
46 #include <rfb/util.h>
47 
48 namespace network { class Socket; }
49 
50 namespace rfb {
51 
52   class VNCServer;
53 
54   class SDesktop : public InputHandler {
55   public:
56     // start() is called by the server when the first client authenticates
57     // successfully, and can be used to begin any expensive tasks which are not
58     // needed when there are no clients.  A valid PixelBuffer must have been
59     // set via the VNCServer's setPixelBuffer() method by the time this call
60     // returns.
61 
62     virtual void start(VNCServer* vs) = 0;
63 
64     // stop() is called by the server when there are no longer any
65     // authenticated clients, and therefore the desktop can cease any
66     // expensive tasks.  No further calls to the VNCServer passed to start()
67     // can be made once stop has returned.
68 
69     virtual void stop() = 0;
70 
71     // queryConnection() is called when a connection has been
72     // successfully authenticated.  The sock and userName arguments
73     // identify the socket and the name of the authenticated user, if
74     // any. At some point later VNCServer::approveConnection() should
75     // be called to either accept or reject the client.
76     virtual void queryConnection(network::Socket* sock,
77                                  const char* userName) = 0;
78 
79     // terminate() is called by the server when it wishes to terminate
80     // itself, e.g. because it was configured to terminate when no one is
81     // using it.
82 
83     virtual void terminate() = 0;
84 
85     // setScreenLayout() requests to reconfigure the framebuffer and/or
86     // the layout of screens.
setScreenLayout(int __unused_attr fb_width,int __unused_attr fb_height,const ScreenSet & __unused_attr layout)87     virtual unsigned int setScreenLayout(int __unused_attr fb_width,
88                                          int __unused_attr fb_height,
89                                          const ScreenSet& __unused_attr layout) {
90       return resultProhibited;
91     }
92 
93     // InputHandler interface
94     // pointerEvent(), keyEvent() and clientCutText() are called in response to
95     // the relevant RFB protocol messages from clients.
96     // See InputHandler for method signatures.
97 
98     // handleClipboardRequest() is called whenever a client requests
99     // the server to send over its clipboard data. It will only be
100     // called after the server has first announced a clipboard change
101     // via VNCServer::announceClipboard().
handleClipboardRequest()102     virtual void handleClipboardRequest() {}
103 
104     // handleClipboardAnnounce() is called to indicate a change in the
105     // clipboard on a client. Call VNCServer::requestClipboard() to
106     // access the actual data.
handleClipboardAnnounce(bool __unused_attr available)107     virtual void handleClipboardAnnounce(bool __unused_attr available) {}
108 
109     // handleClipboardData() is called when a client has sent over
110     // the clipboard data as a result of a previous call to
111     // VNCServer::requestClipboard(). Note that this function might
112     // never be called if the clipboard data was no longer available
113     // when the client received the request.
handleClipboardData(const char * __unused_attr data)114     virtual void handleClipboardData(const char* __unused_attr data) {}
115 
116   protected:
~SDesktop()117     virtual ~SDesktop() {}
118   };
119 
120   // -=- SStaticDesktop
121   //     Trivial implementation of the SDesktop interface, which provides
122   //     dummy input handlers and event processing routine, and exports
123   //     a plain black desktop of the specified format.
124   class SStaticDesktop : public SDesktop {
125   public:
SStaticDesktop(const Point & size)126     SStaticDesktop(const Point& size) : server(0), buffer(0) {
127       PixelFormat pf;
128       const rdr::U8 black[4] = { 0, 0, 0, 0 };
129       buffer = new ManagedPixelBuffer(pf, size.x, size.y);
130       if (buffer)
131         buffer->fillRect(buffer->getRect(), black);
132     }
SStaticDesktop(const Point & size,const PixelFormat & pf)133     SStaticDesktop(const Point& size, const PixelFormat& pf) : buffer(0) {
134       const rdr::U8 black[4] = { 0, 0, 0, 0 };
135       buffer = new ManagedPixelBuffer(pf, size.x, size.y);
136       if (buffer)
137         buffer->fillRect(buffer->getRect(), black);
138     }
~SStaticDesktop()139     virtual ~SStaticDesktop() {
140       if (buffer) delete buffer;
141     }
142 
start(VNCServer * vs)143     virtual void start(VNCServer* vs) {
144       server = vs;
145       server->setPixelBuffer(buffer);
146     }
stop()147     virtual void stop() {
148       server->setPixelBuffer(0);
149       server = 0;
150     }
queryConnection(network::Socket * sock,const char * userName)151     virtual void queryConnection(network::Socket* sock,
152                                  const char* userName) {
153       server->approveConnection(sock, true, NULL);
154     }
155 
156   protected:
157     VNCServer* server;
158     ManagedPixelBuffer* buffer;
159   };
160 
161 };
162 
163 #endif // __RFB_SDESKTOP_H__
164