src/glx/apple/apple_cgl.c

   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
  42 static void *dl_handle = NULL;
  43
  44 struct apple_cgl_api apple_cgl;
  45
  46 static bool initialized = false;
  47
  48 static void *
  49 sym(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
  63 void
  64 apple_cgl_init(void)
  65 {
  66    void *h;
  67    GLint major = 0, minor = 0;
  68    const char *opengl_framework_path;
  69
  70    if (initialized)
  71       return;
  72
  73    opengl_framework_path = getenv("OPENGL_FRAMEWORK_PATH");
  74    if (!opengl_framework_path) {
  75       opengl_framework_path = OPENGL_FRAMEWORK_PATH;
  76    }
  77
  78    (void) dlerror();            /*drain dlerror */
  79    h = dlopen(opengl_framework_path, RTLD_NOW);
  80
  81    if (NULL == h) {
  82       fprintf(stderr, "error: unable to dlopen %s : %s\n",
  83               opengl_framework_path, dlerror());
  84       abort();
  85    }
  86
  87    dl_handle = h;
  88
  89    apple_cgl.get_version = sym(h, "CGLGetVersion");
  90
  91    apple_cgl.get_version(&major, &minor);
  92
  93    apple_glx_diagnostic("CGL major %d minor %d\n", major, minor);
  94
  95    if (1 != major) {
  96       fprintf(stderr, "WARNING: the CGL major version has changed!\n"
  97               "libGL may be incompatible!\n");
  98    }
  99
 100    apple_cgl.choose_pixel_format = sym(h, "CGLChoosePixelFormat");
 101    apple_cgl.destroy_pixel_format = sym(h, "CGLDestroyPixelFormat");
 102
 103    apple_cgl.clear_drawable = sym(h, "CGLClearDrawable");
 104    apple_cgl.flush_drawable = sym(h, "CGLFlushDrawable");
 105
 106    apple_cgl.create_context = sym(h, "CGLCreateContext");
 107    apple_cgl.destroy_context = sym(h, "CGLDestroyContext");
 108
 109    apple_cgl.set_current_context = sym(h, "CGLSetCurrentContext");
 110    apple_cgl.get_current_context = sym(h, "CGLGetCurrentContext");
 111    apple_cgl.error_string = sym(h, "CGLErrorString");
 112
 113    apple_cgl.set_off_screen = sym(h, "CGLSetOffScreen");
 114
 115    apple_cgl.copy_context = sym(h, "CGLCopyContext");
 116
 117    apple_cgl.create_pbuffer = sym(h, "CGLCreatePBuffer");
 118    apple_cgl.destroy_pbuffer = sym(h, "CGLDestroyPBuffer");
 119    apple_cgl.set_pbuffer = sym(h, "CGLSetPBuffer");
 120
 121    initialized = true;
 122 }
 123
 124 void *
 125 apple_cgl_get_dl_handle(void)
 126 {
 127    return dl_handle;
 128 }