src/egl/main/egldriver.c

   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 /**
  32  * Functions for choosing and opening/loading device drivers.
  33  */
  34
  35
  36 #include <assert.h>
  37 #include <string.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include "c11/threads.h"
  41
  42 #include "egldefines.h"
  43 #include "egldisplay.h"
  44 #include "egldriver.h"
  45 #include "egllog.h"
  46
  47 #include "util/debug.h"
  48
  49 extern const _EGLDriver _eglDriver;
  50
  51 /**
  52  * Initialize the display using the driver's function.
  53  * If the initialisation fails, try again using only software rendering.
  54  */
  55 bool
  56 _eglInitializeDisplay(_EGLDisplay *disp)
  57 {
  58    assert(!disp->Initialized);
  59
  60    /* set options */
  61    disp->Options.ForceSoftware =
  62       env_var_as_boolean("LIBGL_ALWAYS_SOFTWARE", false);
  63    if (disp->Options.ForceSoftware)
  64       _eglLog(_EGL_DEBUG, "Found 'LIBGL_ALWAYS_SOFTWARE' set, will use a CPU renderer");
  65
  66    if (_eglDriver.Initialize(disp)) {
  67       disp->Driver = &_eglDriver;
  68       disp->Initialized = EGL_TRUE;
  69       return true;
  70    }
  71
  72    if (disp->Options.ForceSoftware)
  73       return false;
  74
  75    disp->Options.ForceSoftware = EGL_TRUE;
  76    if (!_eglDriver.Initialize(disp))
  77       return false;
  78
  79    disp->Driver = &_eglDriver;
  80    disp->Initialized = EGL_TRUE;
  81    return true;
  82 }
  83
  84 __eglMustCastToProperFunctionPointerType
  85 _eglGetDriverProc(const char *procname)
  86 {
  87    if (_eglDriver.GetProcAddress)
  88       return _eglDriver.GetProcAddress(&_eglDriver, procname);
  89
  90    return NULL;
  91 }