opengl/libs/GLES2/gl2.cpp

   1 /*
   2  ** Copyright 2007, The Android Open Source Project
   3  **
   4  ** Licensed under the Apache License, Version 2.0 (the "License");
   5  ** you may not use this file except in compliance with the License.
   6  ** You may obtain a copy of the License at
   7  **
   8  **     http://www.apache.org/licenses/LICENSE-2.0
   9  **
  10  ** Unless required by applicable law or agreed to in writing, software
  11  ** distributed under the License is distributed on an "AS IS" BASIS,
  12  ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  ** See the License for the specific language governing permissions and
  14  ** limitations under the License.
  15  */
  16
  17 #include <ctype.h>
  18 #include <string.h>
  19 #include <errno.h>
  20
  21 #include <sys/ioctl.h>
  22
  23 #include <GLES2/gl2.h>
  24 #include <GLES2/gl2ext.h>
  25
  26 #include <cutils/log.h>
  27 #include <cutils/properties.h>
  28
  29 #include "hooks.h"
  30 #include "egl_impl.h"
  31
  32 using namespace android;
  33
  34 // ----------------------------------------------------------------------------
  35 // Actual GL entry-points
  36 // ----------------------------------------------------------------------------
  37
  38 #undef API_ENTRY
  39 #undef CALL_GL_API
  40 #undef CALL_GL_API_RETURN
  41
  42 #if USE_FAST_TLS_KEY
  43
  44     #ifdef HAVE_ARM_TLS_REGISTER
  45         #define GET_TLS(reg) \
  46             "mrc p15, 0, " #reg ", c13, c0, 3 \n"
  47     #else
  48         #define GET_TLS(reg) \
  49             "mov   " #reg ", #0xFFFF0FFF      \n"  \
  50             "ldr   " #reg ", [" #reg ", #-15] \n"
  51     #endif
  52
  53     #define API_ENTRY(_api) __attribute__((naked)) _api
  54
  55     #define CALL_GL_API(_api, ...)                              \
  56          asm volatile(                                          \
  57             GET_TLS(r12)                                        \
  58             "ldr   r12, [r12, %[tls]] \n"                       \
  59             "cmp   r12, #0            \n"                       \
  60             "ldrne pc,  [r12, %[api]] \n"                       \
  61             "mov   r0, #0             \n"                       \
  62             "bx    lr                 \n"                       \
  63             :                                                   \
  64             : [tls] "J"(TLS_SLOT_OPENGL_API*4),                 \
  65               [api] "J"(__builtin_offsetof(gl_hooks_t, gl._api))    \
  66             :                                                   \
  67             );
  68
  69     #define CALL_GL_API_RETURN(_api, ...) \
  70         CALL_GL_API(_api, __VA_ARGS__) \
  71         return 0; // placate gcc's warnings. never reached.
  72
  73 #else
  74
  75     #define API_ENTRY(_api) _api
  76
  77     #define CALL_GL_API(_api, ...)                                       \
  78         gl_hooks_t::gl_t const * const _c = &getGlThreadSpecific()->gl;  \
  79         _c->_api(__VA_ARGS__);
  80
  81     #define CALL_GL_API_RETURN(_api, ...)                                \
  82         gl_hooks_t::gl_t const * const _c = &getGlThreadSpecific()->gl;  \
  83         return _c->_api(__VA_ARGS__)
  84
  85 #endif
  86
  87
  88 extern "C" {
  89 #include "gl2_api.in"
  90 #include "gl2ext_api.in"
  91 }
  92
  93 #undef API_ENTRY
  94 #undef CALL_GL_API
  95 #undef CALL_GL_API_RETURN
  96
  97 /*
  98  * glGetString() is special because we expose some extensions in the wrapper
  99  */
 100
 101 extern "C" const GLubyte * __glGetString(GLenum name);
 102
 103 const GLubyte * glGetString(GLenum name)
 104 {
 105     const GLubyte * ret = egl_get_string_for_current_context(name);
 106     if (ret == NULL) {
 107         ret = __glGetString(name);
 108     }
 109     return ret;
 110 }