dolphin/Source/Core/Common/DynamicLibrary.h

77 lines
2.5 KiB
C++

// Copyright 2019 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#pragma once
#include <atomic>
#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);
DynamicLibrary(void* handle);
// Closes the library.
~DynamicLibrary();
DynamicLibrary(const DynamicLibrary&) = delete;
DynamicLibrary(DynamicLibrary&&) = delete;
DynamicLibrary& operator=(const DynamicLibrary&) = delete;
DynamicLibrary& operator=(DynamicLibrary&&) = delete;
DynamicLibrary& operator=(void*);
// 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// Unloads the library, any function pointers from this library are no longer valid.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;
}
private:
// Platform-dependent data type representing a dynamic library handle.
void* m_handle = nullptr;
};
} // namespace Common