pcsx2/common/DynamicLibrary.h

86 lines
3.2 KiB
C++

/* PCSX2 - PS2 Emulator for PCs
* Copyright (C) 2002-2022 PCSX2 Dev Team
*
* PCSX2 is free software: you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* PCSX2 is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with PCSX2.
* If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <string>
namespace Common
{
/**
* Provides a platform-independent interface for loading a dynamic library and retrieving symbols.
* The interface maintains an internal reference count to allow one handle to be shared between
* multiple users.
*/
class DynamicLibrary final
{
public:
/// Default constructor, does not load a library.
DynamicLibrary();
/// Automatically loads the specified library. Call IsOpen() to check validity before use.
DynamicLibrary(const char* filename);
/// Move constructor, transfers ownership.
DynamicLibrary(DynamicLibrary&& move);
/// Closes the library.
~DynamicLibrary();
/// Returns the specified library name with the platform-specific suffix added.
static std::string GetUnprefixedFilename(const char* filename);
/// Returns the specified library name in platform-specific format.
/// Major/minor versions will not be included if set to -1.
/// If libname already contains the "lib" prefix, it will not be added again.
/// Windows: LIBNAME-MAJOR-MINOR.dll
/// Linux: libLIBNAME.so.MAJOR.MINOR
/// Mac: libLIBNAME.MAJOR.MINOR.dylib
static std::string GetVersionedFilename(const char* libname, int major = -1, int minor = -1);
/// Returns true if a module is loaded, otherwise false.
bool IsOpen() const { return m_handle != nullptr; }
/// Loads (or replaces) the handle with the specified library file name.
/// Returns true if the library was loaded and can be used.
bool Open(const char* filename);
/// Unloads the library, any function pointers from this library are no longer valid.
void Close();
/// Returns the address of the specified symbol (function or variable) as an untyped pointer.
/// If the specified symbol does not exist in this library, nullptr is returned.
void* GetSymbolAddress(const char* name) const;
/// Obtains the address of the specified symbol, automatically casting to the correct type.
/// Returns true if the symbol was found and assigned, otherwise false.
template <typename T>
bool GetSymbol(const char* name, T* ptr) const
{
*ptr = reinterpret_cast<T>(GetSymbolAddress(name));
return *ptr != nullptr;
}
/// Move assignment, transfer ownership.
DynamicLibrary& operator=(DynamicLibrary&& move);
private:
DynamicLibrary(const DynamicLibrary&) = delete;
DynamicLibrary& operator=(const DynamicLibrary&) = delete;
/// Platform-dependent data type representing a dynamic library handle.
void* m_handle = nullptr;
};
} // namespace Common