summaryrefslogtreecommitdiff
path: root/glproc_gl.cpp
blob: d032e8b7a866be14d780d705be2ba60f24e97771 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
/**************************************************************************
 *
 * Copyright 2011 Jose Fonseca
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 **************************************************************************/


#include "glproc.hpp"


#if !defined(_WIN32)
#include <unistd.h> // for symlink
#include <dlfcn.h>
#endif


/*
 * Handle to the true OpenGL library.
 */
#if defined(_WIN32)
HINSTANCE __libGlHandle = NULL;
#else
void *__libGlHandle = NULL;
#endif



#if defined(_WIN32)

void *
__getPublicProcAddress(const char *procName)
{
    if (!__libGlHandle) {
        char szDll[MAX_PATH] = {0};
        
        if (!GetSystemDirectoryA(szDll, MAX_PATH)) {
            return NULL;
        }
        
        strcat(szDll, "\\\\opengl32.dll");
        
        __libGlHandle = LoadLibraryA(szDll);
        if (!__libGlHandle) {
            os::log("apitrace: error: couldn't load %s\n", szDll);
            return NULL;
        }
    }
        
    return (void *)GetProcAddress(__libGlHandle, procName);
}


void *
__getPrivateProcAddress(const char *procName) {
    return (void *)__wglGetProcAddress(procName);
}


#elif defined(__APPLE__)


/*
 * Path to the true OpenGL framework
 */
static const char *libgl_filename = "/System/Library/Frameworks/OpenGL.framework/OpenGL";


/*
 * Lookup a libGL symbol
 */
void * __libgl_sym(const char *symbol)
{
    void *result;

    if (!__libGlHandle) {
        /* 
         * Unfortunately we can't just dlopen the true dynamic library because
         * DYLD_LIBRARY_PATH/DYLD_FRAMEWORK_PATH take precedence, even for
         * absolute paths.  So we create a temporary symlink, and dlopen that
         * instead.
         */

        char temp_filename[] = "/tmp/tmp.XXXXXX";

        if (mktemp(temp_filename) != NULL) {
            if (symlink(libgl_filename, temp_filename) == 0) {
                __libGlHandle = dlopen(temp_filename, RTLD_LOCAL | RTLD_NOW | RTLD_FIRST);
                remove(temp_filename);
            }
        }

        if (!__libGlHandle) {
            os::log("apitrace: error: couldn't load %s\n", libgl_filename);
            os::abort();
            return NULL;
        }
    }

    result = dlsym(__libGlHandle, symbol);

#ifndef RETRACE
    if (result == dlsym(RTLD_SELF, symbol)) {
        os::log("apitrace: error: symbol lookup recursion\n");
        os::abort();
        return NULL;
    }
#endif

    return result;
}


void *
__getPublicProcAddress(const char *procName)
{
    return __libgl_sym(procName);
}

void *
__getPrivateProcAddress(const char *procName)
{
    return __libgl_sym(procName);
}


#else


/*
 * Invoke the true dlopen() function.
 */
static void *
__dlopen(const char *filename, int flag)
{
    typedef void * (*PFNDLOPEN)(const char *, int);
    static PFNDLOPEN dlopen_ptr = NULL;

    if (!dlopen_ptr) {
        dlopen_ptr = (PFNDLOPEN)dlsym(RTLD_NEXT, "dlopen");
        if (!dlopen_ptr) {
            os::log("apitrace: error: dlsym(RTLD_NEXT, \"dlopen\") failed\n");
            return NULL;
        }
    }

    return dlopen_ptr(filename, flag);
}


/*
 * Lookup a libGL symbol
 */
void * __libgl_sym(const char *symbol)
{
    void *result;

    if (!__libGlHandle) {
        /*
         * The app doesn't directly link against libGL.so, nor does it directly
         * dlopen it.  So we have to load it ourselves.
         */

        const char * libgl_filename = getenv("TRACE_LIBGL");

        if (!libgl_filename) {
            /*
             * Try to use whatever libGL.so the library is linked against.
             */

            result = dlsym(RTLD_NEXT, symbol);
            if (result) {
                __libGlHandle = RTLD_NEXT;
                return result;
            }

            libgl_filename = "libGL.so.1";
        }

        /*
         * It would have been preferable to use RTLD_LOCAL to ensure that the
         * application can never access libGL.so symbols directly, but this
         * won't work, given libGL.so often loads a driver specific SO and
         * exposes symbols to it.
         */

        __libGlHandle = __dlopen(libgl_filename, RTLD_GLOBAL | RTLD_LAZY);
        if (!__libGlHandle) {
            os::log("apitrace: error: couldn't find libGL.so\n");
            return NULL;
        }
    }

    return dlsym(__libGlHandle, symbol);
}


void *
__getPublicProcAddress(const char *procName)
{
    return __libgl_sym(procName);
}

void *
__getPrivateProcAddress(const char *procName)
{
    return (void *)__glXGetProcAddressARB((const GLubyte *)procName);
}


#endif