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/**
* Copyright (C) 2012, BMW AG
*
* This file is part of GENIVI Project AudioManager.
*
* Contributions are licensed to the GENIVI Alliance under one or more
* Contribution License Agreements.
*
* \copyright
* This Source Code Form is subject to the terms of the
* Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with
* this file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
*
* \author Christian Mueller, christian.ei.mueller@bmw.de BMW 2011,2012
*
* \file TAmPluginTemplate.h
* For further information see http://www.genivi.org/.
*
*/
#ifndef PLUGINTEMPLATE_H_
#define PLUGINTEMPLATE_H_
#include <dlfcn.h>
#include <libgen.h>
#include "shared/CAmDltWrapper.h"
namespace am
{
/**
* * This template tries to load a library and cast to a class
* @param libname the full path to the library to be loaded
* @param libraryHandle the handle to the library that gets returned
* @return returns the pointer to the class to be loaded
*/
template<class T> T* getCreateFunction(const std::string& libname, void*& libraryHandle)
{
logInfo("getCreateFunction : Trying to load library with name: ",libname);
// cut off directories
char* fileWithPath = const_cast<char*>(libname.c_str());
std::string libFileName = basename(fileWithPath);
// cut off "lib" in front and cut off .so end"
std::string createFunctionName = libFileName.substr(3, libFileName.length() - 6) + "Factory";
// open library
dlerror(); // Clear any existing error
libraryHandle = dlopen(libname.c_str(), RTLD_LAZY);
const char* dlopen_error = dlerror();
if (!libraryHandle || dlopen_error)
{
logError("getCreateFunction : dlopen failed",dlopen_error);
return (0);
}
// get entry point from shared lib
dlerror(); // Clear any existing error
union
{
void* voidPointer;
T* typedPointer;
} functionPointer;
// Note: direct cast is not allowed by ISO C++. e.g.
// T* createFunction = reinterpret_cast<T*>(dlsym(libraryHandle, createFunctionName.c_str()));
// compiler warning: "forbids casting between pointer-to-function and pointer-to-object"
functionPointer.voidPointer = dlsym(libraryHandle, createFunctionName.c_str());
T* createFunction = functionPointer.typedPointer;
const char* dlsym_error = dlerror();
if (!createFunction || dlsym_error)
{
logError("getCreateFunction: Failed to load shared lib entry point",dlsym_error);
}
else
{
logInfo("getCreateFunction : loaded successfully plugin", createFunctionName);
}
return (createFunction);
}
}
#endif /* PLUGINTEMPLATE_H_ */
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