QuickDllProxy

A header-only DLL proxy stub generation library built with C++20. No more copy-pasting 100s of DLL exports. No more guessing function parameters.

This project attempts to emulate delayed imports in reverse, i.e. delayed exports. For a somewhat detailed breakdown please read DllProxy.h's header comments or check out the implementation.

Configuration

#define DLL_PROXY_EXPORT_LISTING_FILE "ExportListing.inc"
// Required setting to define the list of proxied exports for this library.

#define DLL_PROXY_TLS_CALLBACK_AUTOINIT
// Optional setting to automatically generate a TLS callback that runs DllProxy::Initialize.

#define DLL_PROXY_CHECK_MISSING_EXPORTS
// Optional setting to enforce that all real exports are found during DllProxy::Initialize. If disabled,
// unresolved export errors will be deferred until proxy functions are invoked.

#define DLL_PROXY_LIBRARY_RESOLVER_CALLBACK MyExampleLibraryResolver
// Optional setting to define a custom function that resolves a DLL's HMODULE. Signature identical to
// DllProxy::DefaultLibraryResolverCallback.

#define DLL_PROXY_EXPORT_RESOLVER_CALLBACK MyExampleExportResolver
// Optional setting to define a custom function that resolves a DLL's exported function. Signature identical to 
// DllProxy::DefaultExportResolverCallback.

#define DLL_PROXY_EXCEPTION_CALLBACK MyExampleExceptionCallback
// Optional setting to define a custom function that's invoked on error. Signature identical to
// DllProxy::DefaultExceptionCallback.

Example Usage

// MySpecialDllFile.cpp
#define DLL_PROXY_EXPORT_LISTING_FILE "ExportListing.inc"   // List of exported functions
#define DLL_PROXY_TLS_CALLBACK_AUTOINIT                     // Enable automatic initialization TLS callback
#define DLL_PROXY_DECLARE_IMPLEMENTATION                    // Define the whole implementation
#include <QuickDllProxy/DllProxy.h>

// ExportListing.inc
DECLARE_PROXIED_LIBRARY("winhttp.dll")
DECLARE_PROXIED_API_ORDINAL("WinHttpAddRequestHeaders", 6)
DECLARE_PROXIED_API_ORDINAL("WinHttpSetSecureLegacyServersAppCompat", 1)
DECLARE_PROXIED_API("TestFunction_1110")

Demo Projects

• WinHttp
• DbgHelp
• Vcpkg Port

Known Limitations

• Exported global variables aren't supported.
• Original exports are resolved at runtime within a TLS callback or DllMain(). In rare cases this is too late to be useful.
• Control flow guard targets aren't valid until after original export resolution.

License

• LGPLv3