1/*
2 * (C) Copyright IBM Corporation 2004
3 * All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * on the rights to use, copy, modify, merge, publish, distribute, sub
9 * license, and/or sell copies of the Software, and to permit persons to whom
10 * the Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
19 * IBM AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 */
24
25/**
26 * \file glx_query.c
27 * Generic utility functions to query internal data from the server.
28 *
29 * \author Ian Romanick <idr@us.ibm.com>
30 */
31
32#include "glxclient.h"
33
34#if defined(USE_XCB)
35# include <X11/Xlib-xcb.h>
36# include <xcb/xcb.h>
37# include <xcb/glx.h>
38#endif
39
40#ifdef USE_XCB
41
42/**
43 * Exchange a protocol request for glXQueryServerString.
44 */
45char *
46__glXQueryServerString(Display * dpy, int opcode, CARD32 screen, CARD32 name)
47{
48   xcb_connection_t *c = XGetXCBConnection(dpy);
49   xcb_glx_query_server_string_reply_t *reply =
50      xcb_glx_query_server_string_reply(c,
51                                        xcb_glx_query_server_string(c,
52                                                                    screen,
53                                                                    name),
54                                        NULL);
55
56   /* The spec doesn't mention this, but the Xorg server replies with
57    * a string already terminated with '\0'. */
58   uint32_t len = xcb_glx_query_server_string_string_length(reply);
59   char *buf = Xmalloc(len);
60   memcpy(buf, xcb_glx_query_server_string_string(reply), len);
61   free(reply);
62
63   return buf;
64}
65
66/**
67 * Exchange a protocol request for glGetString.
68 */
69char *
70__glXGetString(Display * dpy, int opcode, CARD32 contextTag, CARD32 name)
71{
72   xcb_connection_t *c = XGetXCBConnection(dpy);
73   xcb_glx_get_string_reply_t *reply = xcb_glx_get_string_reply(c,
74                                                                xcb_glx_get_string
75                                                                (c,
76                                                                 contextTag,
77                                                                 name),
78                                                                NULL);
79
80   /* The spec doesn't mention this, but the Xorg server replies with
81    * a string already terminated with '\0'. */
82   uint32_t len = xcb_glx_get_string_string_length(reply);
83   char *buf = Xmalloc(len);
84   memcpy(buf, xcb_glx_get_string_string(reply), len);
85   free(reply);
86
87   return buf;
88}
89
90#else
91
92/**
93 * GLX protocol structure for the ficticious "GXLGenericGetString" request.
94 *
95 * This is a non-existant protocol packet.  It just so happens that all of
96 * the real protocol packets used to request a string from the server have
97 * an identical binary layout.  The only difference between them is the
98 * meaning of the \c for_whom field and the value of the \c glxCode.
99 */
100typedef struct GLXGenericGetString
101{
102   CARD8 reqType;
103   CARD8 glxCode;
104   CARD16 length B16;
105   CARD32 for_whom B32;
106   CARD32 name B32;
107} xGLXGenericGetStringReq;
108
109/* These defines are only needed to make the GetReq macro happy.
110 */
111#define sz_xGLXGenericGetStringReq 12
112#define X_GLXGenericGetString 0
113
114/**
115 * Query the Server GLX string.
116 * This routine will allocate the necessay space for the string.
117 */
118static char *
119__glXGetStringFromServer(Display * dpy, int opcode, CARD32 glxCode,
120                         CARD32 for_whom, CARD32 name)
121{
122   xGLXGenericGetStringReq *req;
123   xGLXSingleReply reply;
124   int length;
125   int numbytes;
126   char *buf;
127
128
129   LockDisplay(dpy);
130
131
132   /* All of the GLX protocol requests for getting a string from the server
133    * look the same.  The exact meaning of the for_whom field is usually
134    * either the screen number (for glXQueryServerString) or the context tag
135    * (for GLXSingle).
136    */
137
138   GetReq(GLXGenericGetString, req);
139   req->reqType = opcode;
140   req->glxCode = glxCode;
141   req->for_whom = for_whom;
142   req->name = name;
143
144   _XReply(dpy, (xReply *) & reply, 0, False);
145
146   length = reply.length * 4;
147   numbytes = reply.size;
148
149   buf = (char *) Xmalloc(numbytes);
150   if (buf != NULL) {
151      _XRead(dpy, buf, numbytes);
152      length -= numbytes;
153   }
154
155   _XEatData(dpy, length);
156
157   UnlockDisplay(dpy);
158   SyncHandle();
159
160   return buf;
161}
162
163char *
164__glXQueryServerString(Display * dpy, int opcode, CARD32 screen, CARD32 name)
165{
166   return __glXGetStringFromServer(dpy, opcode,
167                                   X_GLXQueryServerString, screen, name);
168}
169
170char *
171__glXGetString(Display * dpy, int opcode, CARD32 contextTag, CARD32 name)
172{
173   return __glXGetStringFromServer(dpy, opcode, X_GLsop_GetString,
174                                   contextTag, name);
175}
176
177#endif /* USE_XCB */
178