"token" was overloaded (auth tokens, cgo handles, lexer tokens) and didn't say
what it is — a per-call correlation id linking an outgoing {.ffiHost.} call to
the answer that arrives later (possibly from another thread). Renamed across the
runtime (ffi_host / ffi_context), the macro, the exported C ABI (FFIHostFn,
<lib>_host_complete), the Go trampoline, and the tests; regenerated bindings.
The unrelated request-path cgo.Handle result-slot (also informally called a
"token" in go.nim comments) is left as-is — different mechanism.
16 host unit tests + the examples/host_demo Go round-trip stay green.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
5a: record {.ffiHost.} procs in a compile-time registry (FFIHostMeta /
ffiHostRegistry), populated by the macro, so generators can see host fns.
5b: the Go generator emits an idiomatic wrapper over the host C ABI:
- a single //export cgo trampoline backs every host fn; a cgo.Handle in
userData selects the Go closure;
- the closure runs on a fresh GOROUTINE so the FFI thread is never blocked
(the non-blocking contract), then answers via <lib>_host_complete by token;
- a per-host `Set<Name>(func(string) (string, error))` method registers it.
Validated end to end with `go run` (examples/host_demo): Go UseToken -> Nim
{.ffi.} handler -> await fetchToken {.ffiHost.} -> Go trampoline -> goroutine
runs the closure -> host_complete -> future resolves on the loop thread ->
"token[TOK-session]" back in Go. Timer's Go output is unchanged (no host fns);
its regenerated .h just gains the always-exported host ABI decls.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Struct-returning methods now hand back a typed Go struct instead of the raw
CBOR/bytes. Since the native return POD is freed right after the callback, the
POD->Go conversion must happen in-callback: the generator emits a `fromC()`
reader per {.ffi.} type and, per struct-returning proc, an exported Go result
callback. The method calls the native entry point directly with that callback
and a `runtime/cgo.Handle` (boxed in a small C allocation so it travels through
the void* userData checkptr-safe), then blocks until the callback delivers the
typed value or error on the result slot.
String/raw-returning procs keep the existing C-bridge + condvar path. Validated
end-to-end (Echo/Complex/Schedule) including under `go run -race`.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Go generator previously emitted a `// SKIPPED` stub for any proc with a
struct, sequence or optional parameter, leaving Echo/Complex/Schedule
uncallable. Now that the native ABI carries those as flat C-POD structs, the Go
side can marshal them: emit an idiomatic Go struct per {.ffi.} type plus a
`toC()` that builds the matching `C.<Type>` (C.CString for strings, a C array
for seqs, present-flags for options, recursively for nested structs) and
returns cleanup funcs run via defer once the call returns. The native path
deep-copies every argument, so releasing the C buffers immediately is safe.
The C bridge already accepted struct-by-value params via the pass-through type
mapping; only the Go-side conversion and the `allSupported` gate needed work.
Bare seq/Option *top-level* params (not wrapped in a struct) remain skipped, as
the native ABI does not expose them either.
The generated package is now self-contained: the native `<lib>.h` is emitted
beside the `.go`, and the cgo directives use ${SRCDIR} so the header and the
staged library resolve without extra env vars. genbindings_go runs gofmt to
finalize column alignment.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A single {.ffi.} definition now produces BOTH interfaces, chosen by the
caller at link time rather than by a global compile flag:
- `<name>` — native typed-arg C export. Args travel to the FFI thread in
a c_malloc'd C-POD struct passed by pointer (no CBOR), and the
result is delivered to the callback as raw bytes. This is the
preferred path for same-process callers: no serialization on
either side.
- `<name>_cbor` — the existing CBOR-buffer dispatcher, kept for generic /
cross-language callers.
Both share the user's helper proc; they register distinct handlers keyed by
"<Camel>Req" (CBOR) and "<Camel>ReqNative". FFIThreadRequest gains a `cborMode`
flag and a `payloadFree` hook so the native C-POD payload (which owns duplicated
cstring fields) is released correctly and an empty native result is delivered as
a zero-length buffer instead of the CBOR null sentinel. alloc.nim gains
ffiCMalloc/ffiCFree (prefixed to avoid Nim's style-insensitive clash with
ansi_c.c_malloc/c_free).
Verified end-to-end on a scalar-param lib: native calls return raw strings
("calc v1", "sum=42"); the _cbor variant still returns CBOR.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
0.2.0 carries each request as a single CBOR buffer over the exported ABI,
which is awkward for hand-written host bindings (every consumer would have
to encode CBOR and decode responses by hand). These two generators emit
ergonomic, ready-to-use bindings from the same {.ffi.} registry the C++/Rust
generators already consume.
- c.nim (targetLang=c): a self-contained <lib>.h with a small CBOR encoder,
ffi_decode_text(), and `static inline <lib>_<proc>(ctx, cb, ud, args...)`
wrappers that CBOR-encode and forward to the real export. The wrapper keeps
the export's source name but is given a distinct symbol via an __asm__ label
so the raw export's asm alias doesn't bind back to the wrapper (which would
recurse). Scalar/string params only; others fall back to the raw CBOR decl.
- go.nim (targetLang=go): a single <lib>.go cgo package that #includes the
generated <lib>.h and adds a condvar-backed response capture. This is the
key bit: 0.2.0 removed the synchronous fast-path, so a caller can no longer
read a result right after the call — the generated bridges block on the
callback, turning each async export into a blocking Go method. Also emits a
go.mod for importability.
Wired both into genBindings dispatch (targetLang "c"/"go") and added
genbindings_c / genbindings_go tasks. Both verified end-to-end against a
scalar-param test lib (build + run) and the real libwaku surface.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
