Common: Add DynamicLibrary helper class

Source/Core/Common/DynamicLibrary.cpp

@@ -0,0 +1,100 @@
+// Copyright 2019 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include "Common/DynamicLibrary.h"
+#include <cstring>
+#include "Common/Assert.h"
+#include "Common/StringUtil.h"
+
+#ifdef _WIN32
+#include <Windows.h>
+#else
+#include <dlfcn.h>
+#endif
+
+namespace Common
+{
+DynamicLibrary::DynamicLibrary() = default;
+
+DynamicLibrary::DynamicLibrary(const char* filename)
+{
+  Open(filename);
+}
+
+DynamicLibrary::~DynamicLibrary()
+{
+  Close();
+}
+
+std::string DynamicLibrary::GetUnprefixedFilename(const char* filename)
+{
+#if defined(_WIN32)
+  return std::string(filename) + ".dll";
+#elif defined(__APPLE__)
+  return std::string(filename) + ".dylib";
+#else
+  return std::string(filename) + ".so";
+#endif
+}
+
+std::string DynamicLibrary::GetVersionedFilename(const char* libname, int major, int minor)
+{
+#if defined(_WIN32)
+  if (major >= 0 && minor >= 0)
+    return StringFromFormat("%s-%d-%d.dll", libname, major, minor);
+  else if (major >= 0)
+    return StringFromFormat("%s-%d.dll", libname, major);
+  else
+    return StringFromFormat("%s.dll", libname);
+#elif defined(__APPLE__)
+  const char* prefix = std::strncmp(libname, "lib", 3) ? "lib" : "";
+  if (major >= 0 && minor >= 0)
+    return StringFromFormat("%s%s.%d.%d.dylib", prefix, libname, major, minor);
+  else if (major >= 0)
+    return StringFromFormat("%s%s.%d.dylib", prefix, libname, major);
+  else
+    return StringFromFormat("%s%s.dylib", prefix, libname);
+#else
+  const char* prefix = std::strncmp(libname, "lib", 3) ? "lib" : "";
+  if (major >= 0 && minor >= 0)
+    return StringFromFormat("%s%s.so.%d.%d", prefix, libname, major, minor);
+  else if (major >= 0)
+    return StringFromFormat("%s%s.so.%d", prefix, libname, major);
+  else
+    return StringFromFormat("%s%s.so", prefix, libname);
+#endif
+}
+
+bool DynamicLibrary::Open(const char* filename)
+{
+#ifdef _WIN32
+  m_handle = reinterpret_cast<void*>(LoadLibraryA(filename));
+#else
+  m_handle = dlopen(filename, RTLD_NOW);
+#endif
+  return m_handle != nullptr;
+}
+
+void DynamicLibrary::Close()
+{
+  if (!IsOpen())
+    return;
+
+#ifdef _WIN32
+  FreeLibrary(reinterpret_cast<HMODULE>(m_handle));
+#else
+  dlclose(m_handle);
+#endif
+  m_handle = nullptr;
+}
+
+void* DynamicLibrary::GetSymbolAddress(const char* name) const
+{
+#ifdef _WIN32
+  return reinterpret_cast<void*>(GetProcAddress(reinterpret_cast<HMODULE>(m_handle), name));
+#else
+  return reinterpret_cast<void*>(dlsym(m_handle, name));
+#endif
+}
+}  // namespace Common