xref: /third_party/mesa3d/src/mapi/glapi/glapi_nop.c (revision bf215546) 
1/*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
5 * Copyright (C) 2010  VMware, Inc.  All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26
27/**
28 * No-op dispatch table.
29 *
30 * This file defines a special dispatch table which is loaded with no-op
31 * functions.
32 *
33 * Mesa can register a "no-op handler function" which will be called in
34 * the event that a no-op function is called.
35 *
36 * In the past, the dispatch table was loaded with pointers to a single
37 * no-op function.  But that broke on Windows because the GL entrypoints
38 * use __stdcall convention.  __stdcall means the callee cleans up the
39 * stack.  So one no-op function can't properly clean up the stack.  This
40 * would lead to crashes.
41 *
42 * Another benefit of unique no-op functions is we can accurately report
43 * the function's name in an error message.
44 */
45
46
47#include <stdlib.h>
48#include <string.h>
49#include "glapi/glapi_priv.h"
50
51
52void
53_glapi_noop_enable_warnings(unsigned char enable)
54{
55}
56
57void
58_glapi_set_warning_func(_glapi_proc func)
59{
60}
61
62
63/**
64 * We'll jump though this function pointer whenever a no-op function
65 * is called.
66 */
67static _glapi_nop_handler_proc nop_handler = NULL;
68
69
70/**
71 * Register the no-op handler call-back function.
72 */
73void
74_glapi_set_nop_handler(_glapi_nop_handler_proc func)
75{
76   nop_handler = func;
77}
78
79
80/**
81 * Called by each of the no-op GL entrypoints.
82 */
83static void
84nop(const char *func)
85{
86   if (nop_handler)
87      nop_handler(func);
88}
89
90
91/**
92 * This is called if the user somehow calls an unassigned GL dispatch function.
93 */
94static GLint
95NoOpUnused(void)
96{
97   nop("unused GL entry point");
98   return 0;
99}
100
101/*
102 * Defines for the glapitemp.h functions.
103 */
104#define KEYWORD1 static
105#define KEYWORD1_ALT static
106#define KEYWORD2 GLAPIENTRY
107#define NAME(func)  NoOp##func
108#define DISPATCH(func, args, msg)  nop(#func);
109#define RETURN_DISPATCH(func, args, msg)  nop(#func); return 0
110
111
112/*
113 * Defines for the table of no-op entry points.
114 */
115#define TABLE_ENTRY(name) (_glapi_proc) NoOp##name
116#define DISPATCH_TABLE_NAME __glapi_noop_table
117#define UNUSED_TABLE_NAME __unused_noop_functions
118
119#include "glapitemp.h"
120
121
122/** Return pointer to new dispatch table filled with no-op functions */
123struct _glapi_table *
124_glapi_new_nop_table(unsigned num_entries)
125{
126   struct _glapi_table *table = malloc(num_entries * sizeof(_glapi_proc));
127   if (table) {
128      memcpy(table, __glapi_noop_table,
129             num_entries * sizeof(_glapi_proc));
130   }
131   return table;
132}
133