mirror of
https://github.com/logos-messaging/nim-ffi.git
synced 2026-06-21 08:49:34 +00:00
df6dd76311
Increment 4: the exported C surface for host callbacks, plus an end-to-end
test that the host can answer from a different thread than the FFI loop.
- declareLibrary now emits two exportc/cdecl procs on every library's
FFIContext (like the event ABI):
<lib>_register_host_fn(ctx, name, fn, userData)
<lib>_host_complete(ctx, token, ret, msg, len)
(the `name` param is spelled `hostFnName` to dodge the macros.name capture
under quote, same class as the existing id/ret collisions.)
- c.nim emits the FFIHostFn typedef + both declarations into <lib>.h
(guarded, format-agnostic), and the timer header is regenerated.
- Verified: the built timer lib exports both symbols.
The e2e (test_ffi_host_e2e) drives the real bridge: a {.ffi.} handler awaits a
{.ffiHost.} call; the host fn (invoked on the FFI thread, non-blocking) hands
the work to a worker thread, which answers via the completion path. The result
resolves on the loop thread and round-trips correctly (orc+refc). It calls the
underlying registerHostFn/completeHostCall directly, since the exported shims
need an --app:lib build; those shims are verified by the symbol check.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
nim-ffi
Allows exposing Nim projects to other languages
Example
examples/timer is now a self-contained Nimble project that imports nim-ffi directly.
Use cd examples/timer && nimble install -y ../.. && nimble build to compile the example.