mirror of https://github.com/logos-messaging/nim-ffi.git synced 2026-05-06 18:29:27 +00:00

History

1. No timeout → wait_for + 30 s default (ffi/codegen/cpp.nim)
ffi_call_ now takes std::chrono::milliseconds timeout and uses cv.wait_for. All factory/method signatures carry a timeout parameter (default std::chrono::seconds{30}), mirroring the Rust blocking API.

2. Stack-allocated state → shared_ptr ownership (ffi/codegen/cpp.nim)
ffi_cb_ now receives a heap-allocated std::shared_ptr<FfiCallState_>* as user_data. The refcount is 2 going in (one for ffi_call_, one for the callback). If ffi_call_ times out and returns, its copy drops — but the state stays alive (refcount 1) until Nim eventually calls back and delete sptr in ffi_cb_ drops the last reference. No more stack UAF.

3. Destructor + Rule of 5 (ffi/codegen/cpp.nim, examples/nim_timer/nim_timer.nim)

Added nimtimer_destroy to nim_timer.nim with {.dynlib, exportc, cdecl, raises: [].} — joins the FFI and watchdog threads, frees the context
Codegen now always emits void {libName}_destroy(void* ctx) in extern "C" and generates a destructor, deleted copy ctor/assignment, and move ctor/assignment for the context class
timeout_ stored in the class; move transfers it, destructor uses it
4. Hardcoded TimerConfig in createAsync (ffi/codegen/cpp.nim)
createAsync now uses the actual ctorParams list (same as create), so it's correct for any library, not just nim_timer.

5. Opaque exceptions → clear error messages (ffi/codegen/cpp.nim)
deserializeFfiResult wraps nlohmann::json::parse + .get<T>() in a catch that rethrows as "FFI response deserialization failed: ...". The stoull in create() is also try-caught with "FFI create returned non-numeric address: " + raw.

2026-05-04 00:36:52 +02:00

CMakeLists.txt

enhance cpp and rust tokio examples

2026-05-03 15:48:47 +02:00

main.cpp

enhance async cpp

2026-05-03 17:33:06 +02:00

nimtimer.hpp

Fix cpp vulnerabilities

2026-05-04 00:36:52 +02:00

README.md

enhance cpp and rust tokio examples

2026-05-03 15:48:47 +02:00

README.md

C++ Bindings for nim-timer

Purpose

This folder contains auto-generated C++ bindings for the nim_timer Nim library. It is generated from ../nim_timer.nim and provides:

nimtimer.hpp: High-level C++ class (NimTimerCtx) wrapping the FFI interface
main.cpp: Example executable demonstrating how to use the bindings
CMakeLists.txt: Build configuration that compiles the Nim library and links the C++ example

How It's Generated

Generate or regenerate these bindings by running from the parent directory:

cd examples/nim_timer
nimble genbindings_cpp

This command:

Invokes the Nim compiler with -d:targetLang:cpp flag
Triggers genBindings("examples/nim_timer/cpp_bindings", "../nim_timer.nim") in nim_timer.nim
Creates/updates the generated binding files

Building the Example

cd examples/nim_timer/cpp_bindings
cmake -S . -B build
cmake --build build
./build/example

Do Not Edit

The generated files in this folder are overwritten each time nimble genbindings_cpp runs. Any manual changes will be lost.