1 /**************************************************************************
3 * Copyright 2011 Jose Fonseca
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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 NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 **************************************************************************/
32 #define _GNU_SOURCE // for dladdr
39 * Handle to the true OpenGL library.
42 HINSTANCE __libGlHandle = NULL;
44 void *__libGlHandle = NULL;
52 __getPublicProcAddress(const char *procName)
55 char szDll[MAX_PATH] = {0};
57 if (!GetSystemDirectoryA(szDll, MAX_PATH)) {
61 strcat(szDll, "\\\\opengl32.dll");
63 __libGlHandle = LoadLibraryA(szDll);
65 os::log("apitrace: error: couldn't load %s\n", szDll);
70 return (void *)GetProcAddress(__libGlHandle, procName);
75 __getPrivateProcAddress(const char *procName) {
76 return (void *)__wglGetProcAddress(procName);
80 #elif defined(__APPLE__)
84 * Path to the true OpenGL framework
86 static const char *libgl_filename = "/System/Library/Frameworks/OpenGL.framework/OpenGL";
90 * Lookup a libGL symbol
92 void * __libgl_sym(const char *symbol)
98 * Unfortunately we can't just dlopen the true dynamic library because
99 * DYLD_LIBRARY_PATH/DYLD_FRAMEWORK_PATH take precedence, even for
100 * absolute paths. So we create a temporary symlink, and dlopen that
104 char temp_filename[] = "/tmp/tmp.XXXXXX";
106 if (mktemp(temp_filename) != NULL) {
107 if (symlink(libgl_filename, temp_filename) == 0) {
108 __libGlHandle = dlopen(temp_filename, RTLD_LOCAL | RTLD_NOW | RTLD_FIRST);
109 remove(temp_filename);
113 if (!__libGlHandle) {
114 os::log("apitrace: error: couldn't load %s\n", libgl_filename);
120 result = dlsym(__libGlHandle, symbol);
123 if (result == dlsym(RTLD_SELF, symbol)) {
124 os::log("apitrace: error: symbol lookup recursion\n");
135 __getPublicProcAddress(const char *procName)
137 return __libgl_sym(procName);
141 __getPrivateProcAddress(const char *procName)
143 return __libgl_sym(procName);
151 * Invoke the true dlopen() function.
154 __dlopen(const char *filename, int flag)
156 typedef void * (*PFNDLOPEN)(const char *, int);
157 static PFNDLOPEN dlopen_ptr = NULL;
160 dlopen_ptr = (PFNDLOPEN)dlsym(RTLD_NEXT, "dlopen");
162 os::log("apitrace: error: dlsym(RTLD_NEXT, \"dlopen\") failed\n");
167 return dlopen_ptr(filename, flag);
172 * Lookup a libGL symbol
174 void * __libgl_sym(const char *symbol)
178 if (!__libGlHandle) {
180 * The app doesn't directly link against libGL.so, nor does it directly
181 * dlopen it. So we have to load it ourselves.
184 const char * libgl_filename = getenv("TRACE_LIBGL");
186 if (!libgl_filename) {
188 * Try to use whatever libGL.so the library is linked against.
191 result = dlsym(RTLD_NEXT, symbol);
193 __libGlHandle = RTLD_NEXT;
197 libgl_filename = "libGL.so.1";
201 * It would have been preferable to use RTLD_LOCAL to ensure that the
202 * application can never access libGL.so symbols directly, but this
203 * won't work, given libGL.so often loads a driver specific SO and
204 * exposes symbols to it.
207 __libGlHandle = __dlopen(libgl_filename, RTLD_GLOBAL | RTLD_LAZY);
208 if (!__libGlHandle) {
209 os::log("apitrace: error: couldn't find libGL.so\n");
214 return dlsym(__libGlHandle, symbol);
219 __getPublicProcAddress(const char *procName)
221 return __libgl_sym(procName);
225 __getPrivateProcAddress(const char *procName)
227 return (void *)__glXGetProcAddressARB((const GLubyte *)procName);