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# Struct Nemo Relay Native Host ApiV3

> ABI-v3 host extension appended to `NemoRelayNativeHostApiV1`.

Generated from `cargo doc --no-deps -p nemo-relay -p nemo-relay-adaptive -p nemo-relay-pii-redaction -p nemo-relay-ffi -p nemo-relay-types -p nemo-relay-plugin -p nemo-relay-worker-proto -p nemo-relay-worker`.

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ABI-v3 host extension appended to [`NemoRelayNativeHostApiV1`](/reference/api/rust-library-reference/nemo-relay-plugin/struct-nemorelaynativehostapiv1).

Its first field is the complete v1/v2 table, so legacy plugins can keep treating the pointer as a [`NemoRelayNativeHostApiV1`](/reference/api/rust-library-reference/nemo-relay-plugin/struct-nemorelaynativehostapiv1).

## Fields

### `v1: NemoRelayNativeHostApiV1`

Compatibility prefix for ABI-v1/v2 plugins.

### `async_completion_resolve_json: unsafe extern "C" fn(completion: *const NemoRelayNativeAsyncCompletion, value_json: *const NemoRelayNativeString) -> NemoRelayStatus`

Resolves an async callback completion with a JSON value.

### `async_completion_reject: unsafe extern "C" fn(completion: *const NemoRelayNativeAsyncCompletion, message: *const NemoRelayNativeString) -> NemoRelayStatus`

Rejects an async callback completion with a UTF-8 message.

### `async_completion_is_cancelled: unsafe extern "C" fn(completion: *const NemoRelayNativeAsyncCompletion) -> bool`

Returns true after the awaiting runtime has cancelled the invocation.

### `async_completion_release: unsafe extern "C" fn(completion: *const NemoRelayNativeAsyncCompletion)`

Releases the callback-owned reference after a pending completion settles.

### `async_next_invoke: unsafe extern "C" fn(next: *const NemoRelayNativeAsyncNext, invocation_json: *const NemoRelayNativeString, completion: *const NemoRelayNativeAsyncCompletion) -> NemoRelayStatus`

Invokes an execution continuation and settles a supplied completion.

Cancellation of that completion aborts an in-flight continuation. This legacy convenience hook is one-shot because its result settles the middleware completion; use `async_next_invoke_result` for repeated or concurrent calls.

### `async_next_release: unsafe extern "C" fn(next: *const NemoRelayNativeAsyncNext)`

Releases the callback-owned continuation reference.

Execution callbacks must call this exactly once after their final use for both `Complete` and `Pending` return states.

### `plugin_context_register_async_middleware: unsafe extern "C" fn(ctx: *mut NemoRelayNativePluginContext, kind: u32, name: *const NemoRelayNativeString, priority: i32, break_chain: bool, cb: NemoRelayNativeAsyncMiddlewareCb, user_data: *mut c_void, free_fn: NemoRelayNativeFreeFn) -> NemoRelayStatus`

Registers a completion-based asynchronous middleware surface.

`kind` must be a valid [`NemoRelayNativeAsyncMiddlewareKind`](/reference/api/rust-library-reference/nemo-relay-plugin/enum-nemorelaynativeasyncmiddlewarekind) discriminant. The host rejects unknown `u32` values and [`NemoRelayNativeAsyncMiddlewareKind::LlmStreamExecutionIntercept`](/reference/api/rust-library-reference/nemo-relay-plugin/enum-nemorelaynativeasyncmiddlewarekind), which must use `plugin_context_register_async_stream_middleware`.

### `async_stream_push_json: unsafe extern "C" fn(stream: *const NemoRelayNativeAsyncStream, chunk_json: *const NemoRelayNativeString) -> NemoRelayStatus`

Pushes one JSON chunk to an incremental native stream without blocking.

A full bounded host queue returns [`NemoRelayStatus::Internal`](/reference/api/rust-library-reference/nemo-relay-plugin/enum-nemorelaystatus) and records a backpressure message in the host's last-error slot. The producer may retry the logical chunk after the consumer advances.

### `async_stream_finish: unsafe extern "C" fn(stream: *const NemoRelayNativeAsyncStream) -> NemoRelayStatus`

Finishes an incremental native stream successfully.

### `async_stream_reject: unsafe extern "C" fn(stream: *const NemoRelayNativeAsyncStream, message: *const NemoRelayNativeString) -> NemoRelayStatus`

Rejects an incremental native stream without blocking.

A full bounded queue returns [`NemoRelayStatus::Internal`](/reference/api/rust-library-reference/nemo-relay-plugin/enum-nemorelaystatus); the caller may retry the rejection after the consumer advances.

### `async_stream_is_cancelled: unsafe extern "C" fn(stream: *const NemoRelayNativeAsyncStream) -> bool`

Returns true when the consumer cancelled or released the stream.

### `async_stream_release: unsafe extern "C" fn(stream: *const NemoRelayNativeAsyncStream)`

Releases the callback-owned incremental stream reference.

### `async_next_invoke_stream: unsafe extern "C" fn(next: *const NemoRelayNativeAsyncNext, invocation_json: *const NemoRelayNativeString, stream: *const NemoRelayNativeAsyncStream, cb: NemoRelayNativeAsyncNextStreamCb, user_data: *mut c_void) -> NemoRelayStatus`

Invokes a downstream stream and reports chunks incrementally.

The host reports consumer cancellation through one terminal callback with a non-null error. If a result callback returns `false`, it must reclaim its own `user_data` before returning because no terminal callback follows. This hook may be called repeatedly or concurrently with independent callback state while the output stream remains active.

### `plugin_context_register_async_stream_middleware: unsafe extern "C" fn(ctx: *mut NemoRelayNativePluginContext, name: *const NemoRelayNativeString, priority: i32, cb: NemoRelayNativeAsyncStreamMiddlewareCb, user_data: *mut c_void, free_fn: NemoRelayNativeFreeFn) -> NemoRelayStatus`

Registers an incremental asynchronous LLM stream intercept.

### `async_next_invoke_result: unsafe extern "C" fn(next: *const NemoRelayNativeAsyncNext, invocation_json: *const NemoRelayNativeString, cb: NemoRelayNativeAsyncNextResultCb, user_data: *mut c_void) -> NemoRelayStatus`

Invokes a unary execution continuation with an independent result sink.

Unlike the legacy completion-coupled `async_next_invoke`, this hook may be called repeatedly or concurrently with distinct `user_data`.

## Trait Implementations

### `impl Clone for NemoRelayNativeHostApiV3`

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#### `clone`

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#### `clone_from`

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### `impl Copy for NemoRelayNativeHostApiV3`

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### `impl Send for NemoRelayNativeHostApiV3`

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### `impl Sync for NemoRelayNativeHostApiV3`

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