1 /*
2  * Copyright 2007-2008 Peter Hutterer
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21  * DEALINGS IN THE SOFTWARE.
22  *
23  * Author: Peter Hutterer, University of South Australia, NICTA
24  */
25 
26 #ifdef HAVE_DIX_CONFIG_H
27 #include <dix-config.h>
28 #endif
29 #include "windowstr.h"
30 #include <X11/extensions/ge.h>
31 
32 #include "geint.h"
33 #include "geext.h"
34 #include "protocol-versions.h"
35 #include "extinit.h"
36 
37 DevPrivateKeyRec GEClientPrivateKeyRec;
38 
39 GEExtension GEExtensions[MAXEXTENSIONS];
40 
41 /* Major available requests */
42 static const int version_requests[] = {
43     X_GEQueryVersion,           /* before client sends QueryVersion */
44     X_GEQueryVersion,           /* must be set to last request in version 1 */
45 };
46 
47 /* Forward declarations */
48 static void SGEGenericEvent(xEvent *from, xEvent *to);
49 
50 #define EXT_MASK(ext) ((ext) & 0x7F)
51 
52 /************************************************************/
53 /*                request handlers                          */
54 /************************************************************/
55 
56 static int
ProcGEQueryVersion(ClientPtr client)57 ProcGEQueryVersion(ClientPtr client)
58 {
59     GEClientInfoPtr pGEClient = GEGetClient(client);
60     xGEQueryVersionReply rep;
61 
62     REQUEST(xGEQueryVersionReq);
63 
64     REQUEST_SIZE_MATCH(xGEQueryVersionReq);
65 
66     rep = (xGEQueryVersionReply) {
67         .repType = X_Reply,
68         .RepType = X_GEQueryVersion,
69         .sequenceNumber = client->sequence,
70         .length = 0,
71 
72         /* return the supported version by the server */
73         .majorVersion = SERVER_GE_MAJOR_VERSION,
74         .minorVersion = SERVER_GE_MINOR_VERSION
75     };
76 
77     /* Remember version the client requested */
78     pGEClient->major_version = stuff->majorVersion;
79     pGEClient->minor_version = stuff->minorVersion;
80 
81     if (client->swapped) {
82         swaps(&rep.sequenceNumber);
83         swapl(&rep.length);
84         swaps(&rep.majorVersion);
85         swaps(&rep.minorVersion);
86     }
87 
88     WriteToClient(client, sizeof(xGEQueryVersionReply), &rep);
89     return Success;
90 }
91 
92 static int (*ProcGEVector[GENumberRequests]) (ClientPtr) = {
93     /* Version 1.0 */
94     ProcGEQueryVersion,
95 };
96 
97 /************************************************************/
98 /*                swapped request handlers                  */
99 /************************************************************/
100 static int _X_COLD
SProcGEQueryVersion(ClientPtr client)101 SProcGEQueryVersion(ClientPtr client)
102 {
103     REQUEST(xGEQueryVersionReq);
104 
105     swaps(&stuff->length);
106     REQUEST_SIZE_MATCH(xGEQueryVersionReq);
107     swaps(&stuff->majorVersion);
108     swaps(&stuff->minorVersion);
109     return (*ProcGEVector[stuff->ReqType]) (client);
110 }
111 
112 static int (*SProcGEVector[GENumberRequests]) (ClientPtr) = {
113     /* Version 1.0 */
114     SProcGEQueryVersion
115 };
116 
117 /************************************************************/
118 /*                callbacks                                 */
119 /************************************************************/
120 
121 /* dispatch requests */
122 static int
ProcGEDispatch(ClientPtr client)123 ProcGEDispatch(ClientPtr client)
124 {
125     GEClientInfoPtr pGEClient = GEGetClient(client);
126 
127     REQUEST(xGEReq);
128 
129     if (pGEClient->major_version >= ARRAY_SIZE(version_requests))
130         return BadRequest;
131     if (stuff->ReqType > version_requests[pGEClient->major_version])
132         return BadRequest;
133 
134     return (ProcGEVector[stuff->ReqType]) (client);
135 }
136 
137 /* dispatch swapped requests */
138 static int _X_COLD
SProcGEDispatch(ClientPtr client)139 SProcGEDispatch(ClientPtr client)
140 {
141     REQUEST(xGEReq);
142     if (stuff->ReqType >= GENumberRequests)
143         return BadRequest;
144     return (*SProcGEVector[stuff->ReqType]) (client);
145 }
146 
147 /* Reset extension. Called on server shutdown. */
148 static void
GEResetProc(ExtensionEntry * extEntry)149 GEResetProc(ExtensionEntry * extEntry)
150 {
151     EventSwapVector[GenericEvent] = NotImplemented;
152 }
153 
154 /*  Calls the registered event swap function for the extension.
155  *
156  *  Each extension can register a swap function to handle GenericEvents being
157  *  swapped properly. The server calls SGEGenericEvent() before the event is
158  *  written on the wire, this one calls the registered swap function to do the
159  *  work.
160  */
161 static void _X_COLD
SGEGenericEvent(xEvent * from,xEvent * to)162 SGEGenericEvent(xEvent *from, xEvent *to)
163 {
164     xGenericEvent *gefrom = (xGenericEvent *) from;
165     xGenericEvent *geto = (xGenericEvent *) to;
166 
167     if ((gefrom->extension & 0x7f) > MAXEXTENSIONS) {
168         ErrorF("GE: Invalid extension offset for event.\n");
169         return;
170     }
171 
172     if (GEExtensions[EXT_MASK(gefrom->extension)].evswap)
173         GEExtensions[EXT_MASK(gefrom->extension)].evswap(gefrom, geto);
174 }
175 
176 /* Init extension, register at server.
177  * Since other extensions may rely on XGE (XInput does already), it is a good
178  * idea to init XGE first, before any other extension.
179  */
180 void
GEExtensionInit(void)181 GEExtensionInit(void)
182 {
183     ExtensionEntry *extEntry;
184 
185     if (!dixRegisterPrivateKey
186         (&GEClientPrivateKeyRec, PRIVATE_CLIENT, sizeof(GEClientInfoRec)))
187         FatalError("GEExtensionInit: GE private request failed.\n");
188 
189     if ((extEntry = AddExtension(GE_NAME,
190                                  0, GENumberErrors,
191                                  ProcGEDispatch, SProcGEDispatch,
192                                  GEResetProc, StandardMinorOpcode)) != 0) {
193         memset(GEExtensions, 0, sizeof(GEExtensions));
194 
195         EventSwapVector[GenericEvent] = (EventSwapPtr) SGEGenericEvent;
196     }
197     else {
198         FatalError("GEInit: AddExtensions failed.\n");
199     }
200 
201 }
202 
203 /************************************************************/
204 /*                interface for extensions                  */
205 /************************************************************/
206 
207 /* Register an extension with GE. The given swap function will be called each
208  * time an event is sent to a client with different byte order.
209  * @param extension The extensions major opcode
210  * @param ev_swap The event swap function.
211  * @param ev_fill Called for an event before delivery. The extension now has
212  * the chance to fill in necessary fields for the event.
213  */
214 void
GERegisterExtension(int extension,void (* ev_swap)(xGenericEvent * from,xGenericEvent * to))215 GERegisterExtension(int extension,
216                     void (*ev_swap) (xGenericEvent *from, xGenericEvent *to))
217 {
218     if (EXT_MASK(extension) >= MAXEXTENSIONS)
219         FatalError("GE: extension > MAXEXTENSIONS. This should not happen.\n");
220 
221     /* extension opcodes are > 128, might as well save some space here */
222     GEExtensions[EXT_MASK(extension)].evswap = ev_swap;
223 }
224 
225 /* Sets type and extension field for a generic event. This is just an
226  * auxiliary function, extensions could do it manually too.
227  */
228 void
GEInitEvent(xGenericEvent * ev,int extension)229 GEInitEvent(xGenericEvent *ev, int extension)
230 {
231     ev->type = GenericEvent;
232     ev->extension = extension;
233     ev->length = 0;
234 }
235