apple_cgl.c revision df1dacf093058e74ec102d8828d2751a9ed6e34e 
1/*
2 Copyright (c) 2008 Apple Inc.
3
4 Permission is hereby granted, free of charge, to any person
5 obtaining a copy of this software and associated documentation files
6 (the "Software"), to deal in the Software without restriction,
7 including without limitation the rights to use, copy, modify, merge,
8 publish, distribute, sublicense, and/or sell copies of the Software,
9 and to permit persons to whom the Software is furnished to do so,
10 subject to the following conditions:
11
12 The above copyright notice and this permission notice shall be
13 included in all copies or substantial portions of the Software.
14
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 NONINFRINGEMENT.  IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT
19 HOLDER(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
20 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
22 DEALINGS IN THE SOFTWARE.
23
24 Except as contained in this notice, the name(s) of the above
25 copyright holders shall not be used in advertising or otherwise to
26 promote the sale, use or other dealings in this Software without
27 prior written authorization.
28*/
29
30#include <stdbool.h>
31#include <stdio.h>
32#include <stdlib.h>
33#include <dlfcn.h>
34
35#include "apple_cgl.h"
36#include "apple_glx.h"
37
38#ifndef OPENGL_FRAMEWORK_PATH
39#define OPENGL_FRAMEWORK_PATH "/System/Library/Frameworks/OpenGL.framework/Versions/A/OpenGL"
40#endif
41
42static void *dl_handle = NULL;
43
44struct apple_cgl_api apple_cgl;
45
46static bool initialized = false;
47
48static void *
49sym(void *h, const char *name)
50{
51   void *s;
52
53   s = dlsym(h, name);
54
55   if (NULL == s) {
56      fprintf(stderr, "error: %s\n", dlerror());
57      abort();
58   }
59
60   return s;
61}
62
63void
64apple_cgl_init(void)
65{
66   void *h;
67   const char *opengl_framework_path;
68
69   if (initialized)
70      return;
71
72   opengl_framework_path = getenv("OPENGL_FRAMEWORK_PATH");
73   if (!opengl_framework_path) {
74      opengl_framework_path = OPENGL_FRAMEWORK_PATH;
75   }
76
77   (void) dlerror();            /*drain dlerror */
78   h = dlopen(opengl_framework_path, RTLD_NOW);
79
80   if (NULL == h) {
81      fprintf(stderr, "error: unable to dlopen %s : %s\n",
82              opengl_framework_path, dlerror());
83      abort();
84   }
85
86   dl_handle = h;
87
88   apple_cgl.get_version = sym(h, "CGLGetVersion");
89
90   apple_cgl.get_version(&apple_cgl.version_major, &apple_cgl.version_minor);
91
92   apple_glx_diagnostic("CGL major %d minor %d\n", apple_cgl.version_major, apple_cgl.version_minor);
93
94   if (1 != apple_cgl.version_major) {
95      fprintf(stderr, "WARNING: the CGL major version has changed!\n"
96              "libGL may be incompatible!\n");
97   }
98
99   apple_cgl.choose_pixel_format = sym(h, "CGLChoosePixelFormat");
100   apple_cgl.destroy_pixel_format = sym(h, "CGLDestroyPixelFormat");
101
102   apple_cgl.clear_drawable = sym(h, "CGLClearDrawable");
103   apple_cgl.flush_drawable = sym(h, "CGLFlushDrawable");
104
105   apple_cgl.create_context = sym(h, "CGLCreateContext");
106   apple_cgl.destroy_context = sym(h, "CGLDestroyContext");
107
108   apple_cgl.set_current_context = sym(h, "CGLSetCurrentContext");
109   apple_cgl.get_current_context = sym(h, "CGLGetCurrentContext");
110   apple_cgl.error_string = sym(h, "CGLErrorString");
111
112   apple_cgl.set_off_screen = sym(h, "CGLSetOffScreen");
113
114   apple_cgl.copy_context = sym(h, "CGLCopyContext");
115
116   apple_cgl.create_pbuffer = sym(h, "CGLCreatePBuffer");
117   apple_cgl.destroy_pbuffer = sym(h, "CGLDestroyPBuffer");
118   apple_cgl.set_pbuffer = sym(h, "CGLSetPBuffer");
119
120   initialized = true;
121}
122
123void *
124apple_cgl_get_dl_handle(void)
125{
126   return dl_handle;
127}
128