1 /**************************************************************************
2 *
3 * Copyright 2008 VMware, Inc.
4 * Copyright 2009-2010 Chia-I Wu <olvaffe@gmail.com>
5 * Copyright 2010-2011 LunarG, Inc.
6 * All Rights Reserved.
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the
10 * "Software"), to deal in the Software without restriction, including
11 * without limitation the rights to use, copy, modify, merge, publish,
12 * distribute, sub license, and/or sell copies of the Software, and to
13 * permit persons to whom the Software is furnished to do so, subject to
14 * the following conditions:
15 *
16 * The above copyright notice and this permission notice (including the
17 * next paragraph) shall be included in all copies or substantial portions
18 * of the Software.
19 *
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26 * DEALINGS IN THE SOFTWARE.
27 *
28 **************************************************************************/
29
30
31 #include <stdlib.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <assert.h>
35 #include "c11/threads.h"
36
37 #include "eglglobals.h"
38 #include "egldevice.h"
39 #include "egldisplay.h"
40
41 #include "util/macros.h"
42 #include "util/os_misc.h"
43
44 #ifdef HAVE_MINCORE
45 #include <unistd.h>
46 #include <sys/mman.h>
47 #endif
48
49
50 static mtx_t _eglGlobalMutex = _MTX_INITIALIZER_NP;
51
52 struct _egl_global _eglGlobal =
53 {
54 .Mutex = &_eglGlobalMutex,
55 .DisplayList = NULL,
56 .DeviceList = &_eglSoftwareDevice,
57 .NumAtExitCalls = 2,
58 .AtExitCalls = {
59 /* default AtExitCalls, called in reverse order */
60 _eglFiniDevice, /* always called last */
61 _eglFiniDisplay,
62 },
63
64 #if USE_LIBGLVND
65 .ClientOnlyExtensionString =
66 #else
67 .ClientExtensionString =
68 #endif
69 "EGL_EXT_client_extensions"
70 " EGL_EXT_device_base"
71 " EGL_EXT_device_enumeration"
72 " EGL_EXT_device_query"
73 " EGL_EXT_platform_base"
74 " EGL_KHR_client_get_all_proc_addresses"
75 " EGL_KHR_debug"
76
77 #if USE_LIBGLVND
78 ,
79 .PlatformExtensionString =
80 #else
81 " "
82 #endif
83
84 "EGL_EXT_platform_device"
85 #ifdef HAVE_WAYLAND_PLATFORM
86 " EGL_EXT_platform_wayland"
87 " EGL_KHR_platform_wayland"
88 #endif
89 #ifdef HAVE_X11_PLATFORM
90 " EGL_EXT_platform_x11"
91 " EGL_KHR_platform_x11"
92 #endif
93 #ifdef HAVE_XCB_PLATFORM
94 " EGL_MESA_platform_xcb"
95 #endif
96 #ifdef HAVE_DRM_PLATFORM
97 " EGL_MESA_platform_gbm"
98 " EGL_KHR_platform_gbm"
99 #endif
100 " EGL_MESA_platform_surfaceless"
101 "",
102
103 .debugCallback = NULL,
104 .debugTypesEnabled = _EGL_DEBUG_BIT_CRITICAL | _EGL_DEBUG_BIT_ERROR,
105 };
106
107
108 static void
_eglAtExit(void)109 _eglAtExit(void)
110 {
111 EGLint i;
112 for (i = _eglGlobal.NumAtExitCalls - 1; i >= 0; i--)
113 _eglGlobal.AtExitCalls[i]();
114 }
115
116
117 void
_eglAddAtExitCall(void (* func)(void))118 _eglAddAtExitCall(void (*func)(void))
119 {
120 if (func) {
121 static EGLBoolean registered = EGL_FALSE;
122
123 mtx_lock(_eglGlobal.Mutex);
124
125 if (!registered) {
126 atexit(_eglAtExit);
127 registered = EGL_TRUE;
128 }
129
130 assert(_eglGlobal.NumAtExitCalls < ARRAY_SIZE(_eglGlobal.AtExitCalls));
131 _eglGlobal.AtExitCalls[_eglGlobal.NumAtExitCalls++] = func;
132
133 mtx_unlock(_eglGlobal.Mutex);
134 }
135 }
136
137 EGLBoolean
_eglPointerIsDereferencable(void * p)138 _eglPointerIsDereferencable(void *p)
139 {
140 uintptr_t addr = (uintptr_t) p;
141 uint64_t page_size = 0;
142 os_get_page_size(&page_size);
143 #ifdef HAVE_MINCORE
144 unsigned char valid = 0;
145
146 if (p == NULL)
147 return EGL_FALSE;
148
149 /* align addr to page_size */
150 addr &= ~(page_size - 1);
151
152 /* mincore expects &valid to be unsigned char* on Linux but char* on BSD:
153 * we cast pointers to void, to fix type mismatch warnings in all systems
154 */
155 if (mincore((void *) addr, page_size, (void*)&valid) < 0) {
156 return EGL_FALSE;
157 }
158
159 /* mincore() returns 0 on success, and -1 on failure. The last parameter
160 * is a vector of bytes with one entry for each page queried. mincore
161 * returns page residency information in the first bit of each byte in the
162 * vector.
163 *
164 * Residency doesn't actually matter when determining whether a pointer is
165 * dereferenceable, so the output vector can be ignored. What matters is
166 * whether mincore succeeds. See:
167 *
168 * http://man7.org/linux/man-pages/man2/mincore.2.html
169 */
170 return EGL_TRUE;
171 #else
172 // Without mincore(), we just assume that the first page is unmapped.
173 return addr >= page_size;
174 #endif
175 }
176