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
52 void
_glapi_noop_enable_warnings(unsigned char enable)53 _glapi_noop_enable_warnings(unsigned char enable)
54 {
55 }
56
57 void
_glapi_set_warning_func(_glapi_proc func)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 */
67 static _glapi_nop_handler_proc nop_handler = NULL;
68
69
70 /**
71 * Register the no-op handler call-back function.
72 */
73 void
_glapi_set_nop_handler(_glapi_nop_handler_proc func)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 */
83 static void
nop(const char * func)84 nop(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 */
94 static GLint
NoOpUnused(void)95 NoOpUnused(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 "glapi/glapitemp.h"
120
121
122 /** Return pointer to new dispatch table filled with no-op functions */
123 struct _glapi_table *
_glapi_new_nop_table(unsigned num_entries)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