Home | History | Annotate | Download | only in egl 
      1 /*
      2 * Copyright (C) 2011 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 #include "ClientAPIExts.h"
     17 #include "ThreadInfo.h"
     18 #include <GLES/gl.h>
     19 #include <GLES/glext.h>
     20 #include "eglContext.h"
     21 
     22 namespace ClientAPIExts
     23 {
     24 
     25 //
     26 // define function pointer type for each extention function
     27 // typename has the form __egl_{funcname}_t
     28 //
     29 #define FUNC_TYPE(fname) __egl_ ## fname ## _t
     30 // NOLINT: clang-tidy adds parentheses around 'params'.
     31 #define API_ENTRY(fname,params,args) \
     32     typedef void (GL_APIENTRY *FUNC_TYPE(fname)) params;  // NOLINT
     33 
     34 #define API_ENTRY_RET(rtype,fname,params,args) \
     35     typedef rtype (GL_APIENTRY *FUNC_TYPE(fname)) params;  // NOLINT
     36 
     37 #include "ClientAPIExts.in"
     38 #undef API_ENTRY
     39 #undef API_ENTRY_RET
     40 
     41 /////
     42 // Define static table to store the function value for each
     43 // client API. functions pointers will get initialized through
     44 // ClientAPIExts::initClientFuncs function after each client API has been
     45 // loaded.
     46 /////
     47 #define API_ENTRY(fname,params,args) \
     48     FUNC_TYPE(fname) (fname);
     49 
     50 #define API_ENTRY_RET(rtype,fname,params,args) \
     51     API_ENTRY(fname,params,args)
     52 
     53 static struct _ext_table
     54 {
     55 #include "ClientAPIExts.in"
     56 } s_client_extensions[2];
     57 
     58 #undef API_ENTRY
     59 #undef API_ENTRY_RET
     60 
     61 //
     62 // This function initialized each entry in the s_client_extensions
     63 // struct at the givven index using the givven client interface
     64 //
     65 void initClientFuncs(const EGLClient_glesInterface *iface, int idx)
     66 {
     67 #define API_ENTRY(fname,params,args) \
     68     s_client_extensions[idx].fname = \
     69           (FUNC_TYPE(fname))iface->getProcAddress(#fname);
     70 
     71 #define API_ENTRY_RET(rtype,fname,params,args) \
     72     API_ENTRY(fname,params,args)
     73 
     74     //
     75     // reset all func pointers to NULL
     76     //
     77     memset(&s_client_extensions[idx], 0, sizeof(struct _ext_table));
     78 
     79     //
     80     // And now query the GLES library for each proc address
     81     //
     82 #include "ClientAPIExts.in"
     83 #undef API_ENTRY
     84 #undef API_ENTRY_RET
     85 }
     86 
     87 //
     88 // Define implementation for each extension function which checks
     89 // the current context version and calls to the correct client API
     90 // function.
     91 //
     92 // NOLINT: clang-tidy adds parentheses around 'args'.
     93 #define API_ENTRY(fname,params,args) \
     94     static void _egl_ ## fname params \
     95     { \
     96         EGLThreadInfo* thread  = getEGLThreadInfo(); \
     97         if (!thread->currentContext) { \
     98             return; \
     99         } \
    100         int clientMajorVersion = (int)thread->currentContext->majorVersion; \
    101         int idx = clientMajorVersion == 1 ? 0 : 1; \
    102         if (!s_client_extensions[idx].fname) { \
    103             return; \
    104         } \
    105         (*s_client_extensions[idx].fname) args; /* NOLINT */ \
    106     }
    107 
    108 #define API_ENTRY_RET(rtype,fname,params,args) \
    109     static rtype _egl_ ## fname params \
    110     { \
    111         EGLThreadInfo* thread  = getEGLThreadInfo(); \
    112         if (!thread->currentContext) { \
    113             return (rtype)0; \
    114         } \
    115         int idx = (int)thread->currentContext->majorVersion - 1; \
    116         if (!s_client_extensions[idx].fname) { \
    117             return (rtype)0; \
    118         } \
    119         return (*s_client_extensions[idx].fname) args; /* NOLINT */ \
    120     }
    121 
    122 #include "ClientAPIExts.in"
    123 #undef API_ENTRY
    124 #undef API_ENTRY_RET
    125 
    126 //
    127 // Define a table to map function names to the local _egl_ version of
    128 // the extension function, to be used in eglGetProcAddress.
    129 //
    130 #define API_ENTRY(fname,params,args) \
    131     { #fname, (void*)_egl_ ## fname},
    132 #define API_ENTRY_RET(rtype,fname,params,args) \
    133     API_ENTRY(fname,params,args)
    134 
    135 static const struct _client_ext_funcs {
    136     const char *fname;
    137     void* proc;
    138 } s_client_ext_funcs[] = {
    139 #include "ClientAPIExts.in"
    140 };
    141 static const int numExtFuncs = sizeof(s_client_ext_funcs) /
    142                                sizeof(s_client_ext_funcs[0]);
    143 
    144 #undef API_ENTRY
    145 #undef API_ENTRY_RET
    146 
    147 //
    148 // returns the __egl_ version of the givven extension function name.
    149 //
    150 void* getProcAddress(const char *fname)
    151 {
    152     for (int i=0; i<numExtFuncs; i++) {
    153         if (!strcmp(fname, s_client_ext_funcs[i].fname)) {
    154             return s_client_ext_funcs[i].proc;
    155         }
    156     }
    157     return NULL;
    158 }
    159 
    160 } // of namespace ClientAPIExts
    161