Ivan FB 825ae5af06
feat(ffi): RET_STALE_WARN progress callback replacing handler timeout
nim-ffi never times a handler out: a hard-cancel mid-call into the
underlying library (Waku/libp2p) can leave it half-applied. Instead, while
a request is still in flight its result callback receives a non-terminal
RET_STALE_WARN every StaleWarnInterval (5s default, Android's ANR interval;
-d:ffiStaleWarnIntervalMs to override), carrying the elapsed milliseconds as
a decimal string. The request always ends with exactly one terminal
RET_OK/RET_ERR — the dev decides what to do with a slow one, nim-ffi does
not decide for them.

This replaces the never-released per-proc {.ffi: "timeout = <ms>".} override
and the defaultRequestTimeout context field (issue #93), whose hard abort
unblocked the caller early. The stale-warn interval is an internal context
seam (staleWarnInterval), not a per-proc pragma.

Codegen: emit RET_STALE_WARN in the C/C++ headers, and guard every generated
trampoline (C, C++, Rust, and the Nim abi=c reply trampolines) to early-return
on the non-terminal code so the repeated callback can't double-free the
one-shot reply box. Typed wrappers ignore the progress signal for now; it is
delivered at the raw result-callback boundary.

Closes #126.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-07-11 00:59:26 +02:00
..
2026-05-16 01:08:42 +02:00

timer example

This example is a self-contained Nimble project demonstrating how to import nim-ffi and use the .ffiCtor. / .ffi. abstraction.

Usage

  1. Change into the example directory:

    cd examples/timer
    
  2. Install the local ffi dependency:

    nimble install -y ../..
    
  3. Build the example library:

    nimble build
    
  4. Generate bindings:

    nimble genbindings_rust
    nimble genbindings_cpp
    

Rust example clients

The Rust client lives in examples/timer/rust_client.

  • Run the sync example:

    cd examples/timer/rust_client
    cargo run --bin rust_client
    
  • Run the Tokio example:

    cd examples/timer/rust_client
    cargo run --bin tokio_client
    

C++ example

The generated C++ example lives in examples/timer/cpp_bindings.

Build and run it with:

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