1 files changed, 121 insertions, 0 deletions
diff --git a/zen/dll.h b/zen/dll.h
new file mode 100644
index 00000000..f6422fa7
--- /dev/null
+++ b/zen/dll.h
@@ -0,0 +1,121 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) Zenju (zenju AT gmx DOT de) - All Rights Reserved        *
+// **************************************************************************
+
+#ifndef DLLLOADER_H_4239582598670968
+#define DLLLOADER_H_4239582598670968
+
+#include <memory>
+#ifdef ZEN_WIN
+#include <string>
+#include "scope_guard.h"
+#include "win.h" //includes "windows.h"
+
+#elif defined ZEN_LINUX || defined ZEN_MAC
+#include <dlfcn.h>
+#endif
+
+namespace zen
+{
+/*
+Manage DLL function and library ownership
+   - thread safety: like built-in type
+   - full value semantics
+
+ Usage:
+    typedef BOOL (WINAPI* FunType_IsWow64Process)(HANDLE hProcess, PBOOL Wow64Process);
+    const zen::SysDllFun<FunType_IsWow64Process> isWow64Process(L"kernel32.dll", "IsWow64Process");
+    if (isWow64Process) ... use function ptr ...
+
+ Usage 2:
+	#define DEF_DLL_FUN(name) DllFun<dll_ns::FunType_##name> name(dll_ns::getDllName(), dll_ns::funName_##name);
+	DEF_DLL_FUN(funname1); DEF_DLL_FUN(funname2); DEF_DLL_FUN(funname3);
+*/
+
+template <class Func>
+class DllFun
+{
+public:
+    DllFun() : fun(nullptr) {}
+
+#ifdef ZEN_WIN
+    DllFun(const wchar_t* libraryName, const char* functionName) :
+        hLibRef(::LoadLibrary(libraryName), ::FreeLibrary),
+        fun(hLibRef ? reinterpret_cast<Func>(::GetProcAddress(static_cast<HMODULE>(hLibRef.get()), functionName)) : nullptr) {}
+#elif defined ZEN_LINUX || defined ZEN_MAC
+    DllFun(const char* libraryName, const char* functionName) :
+        hLibRef(::dlopen(libraryName, RTLD_LAZY), ::dlclose),
+        fun(hLibRef ? reinterpret_cast<Func>(::dlsym(hLibRef.get(), functionName)) : nullptr) {}
+#endif
+    operator Func() const { return fun; }
+
+private:
+    std::shared_ptr<void> hLibRef; //we would prefer decltype(*HMODULE()) if only it would work...
+    Func fun;
+};
+
+
+#ifdef ZEN_WIN
+//if the dll is already part of the process space, e.g. "kernel32.dll" or "shell32.dll", we can use a faster variant:
+//NOTE: since the lifetime of the referenced library is *not* controlled, this is safe to use only for permanently loaded libraries like these!
+template <class Func>
+class SysDllFun
+{
+public:
+    SysDllFun() : fun(nullptr) {}
+
+    SysDllFun(const wchar_t* systemLibrary, const char* functionName)
+    {
+        HMODULE mod = ::GetModuleHandle(systemLibrary);
+        fun = mod ? reinterpret_cast<Func>(::GetProcAddress(mod, functionName)) : nullptr;
+    }
+
+    operator Func() const { return fun; }
+
+private:
+    Func fun;
+};
+
+/*
+extract binary resources from .exe/.dll:
+
+-- resource.h --
+#define MY_BINARY_RESOURCE 1337
+
+-- resource.rc --
+MY_BINARY_RESOURCE RCDATA "filename.dat"
+*/
+std::string getResourceStream(const std::wstring& libraryName, size_t resourceId);
+#endif
+
+
+
+
+
+
+
+
+
+
+//--------------- implementation---------------------------------------------------
+#ifdef ZEN_WIN
+inline
+std::string getResourceStream(const wchar_t* libraryName, size_t resourceId)
+{
+    if (HMODULE module = ::LoadLibrary(libraryName))
+    {
+        ZEN_ON_SCOPE_EXIT(::FreeLibrary(module));
+
+        if (HRSRC res = ::FindResource(module, MAKEINTRESOURCE(resourceId), RT_RCDATA))
+            if (HGLOBAL resHandle = ::LoadResource(module, res))
+                if (const char* stream = static_cast<const char*>(::LockResource(resHandle)))
+                    return std::string(stream, static_cast<size_t>(::SizeofResource(module, res))); //size is 0 on error
+    }
+    return std::string();
+}
+#endif
+}
+
+#endif //DLLLOADER_H_4239582598670968