hybris/hardware/hardware.c

   1 /*
   2  * Copyright (c) 2012 Simon Busch <morphis@gravedo.de>
   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
  18 #include <dlfcn.h>
  19 #include <stddef.h>
  20 #include <android/hardware/hardware.h>
  21 #include <hybris/internal/binding.h>
  22
  23 static void *_libhardware = NULL;
  24
  25 static int (*_hw_get_module)(const char *id, const struct hw_module_t **module) = NULL;
  26
  27 static int (*_hw_get_module_by_class)(const char *class_id, const char *inst, const struct hw_module_t **module) = NULL;
  28
  29 #define HARDWARE_DLSYM(fptr, sym) do { if (_libhardware == NULL) { _init_lib_hardware(); }; if (*(fptr) == NULL) { *(fptr) = (void *) android_dlsym(_libhardware, sym); } } while (0)
  30
  31 static void _init_lib_hardware()
  32 {
  33         _libhardware = (void *) android_dlopen("/system/lib/libhardware.so", RTLD_LAZY);
  34 }
  35
  36 int hw_get_module(const char *id, const struct hw_module_t **module)
  37 {
  38         HARDWARE_DLSYM(&_hw_get_module, "hw_get_module");
  39         return (*_hw_get_module)(id, module);
  40 }
  41
  42 int hw_get_module_by_class(const char *class_id, const char *inst,
  43                            const struct hw_module_t **module)
  44 {
  45         HARDWARE_DLSYM(&_hw_get_module_by_class, "hw_get_module_by_class");
  46         return (*_hw_get_module_by_class)(class_id, inst, module);
  47 }
  48
  49 // vim:ts=4:sw=4:noexpandtab