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wknet

Async HTTP

Async HTTP¶

Namespace: wknet::http
Headers: HttpAsync.h · AsyncOp.h · Options.h · Lifecycle.h · Types.h

Non-blocking send, AsyncOp wait/cancel/result, and Destroy on the driver unload path.

AsyncOptions¶

NTSTATUS AsyncOptionsCreate(_Out_ AsyncOptions** options) noexcept;
void AsyncOptionsRelease(_In_opt_ AsyncOptions* options) noexcept;

struct AsyncOptions final {
    SendOptions Send;
    CompletionCallback OnComplete;
    void* CompletionContext;
};

Field	Default	Notes
`Send`	`DefaultSendOptions()`	Embedded sync send options (Flags, TLS, cache, …)
`OnComplete`	`nullptr`	`void ()(void context, NTSTATUS status)`
`CompletionContext`	`nullptr`	Passed to `OnComplete`

SendOptions fields: Sync HTTP.

AsyncSend / method-specific async send¶

Signatures¶

NTSTATUS AsyncSend(
    _In_ Session* session,
    Method method,
    _In_z_ const char* url,
    _In_opt_ const Headers* headers,
    _In_opt_ const Body* body,
    _In_opt_ const AsyncOptions* options,
    _Out_ AsyncOp** operation) noexcept;

NTSTATUS AsyncSendEx(
    _In_ Session* session,
    Method method,
    _In_reads_bytes_(urlLength) const char* url,
    SIZE_T urlLength,
    _In_opt_ const Headers* headers,
    _In_opt_ const Body* body,
    _In_opt_ const AsyncOptions* options,
    _Out_ AsyncOp** operation) noexcept;

Also Request*-leading AsyncSend / AsyncSendEx.

Methods (Session / Request)	`*Ex`
`AsyncGet` / `AsyncHead` / `AsyncDelete` / `AsyncTrace`	`*Ex(..., headers, options, operation)`
`AsyncPost` / `AsyncPut` / `AsyncPatch`	`*Ex(..., headers, body, options, operation)`
`AsyncOptionsRequest`	`AsyncOptionsRequestEx` (avoids clash with type `AsyncOptions`)

Parameters¶

Param	Meaning
`options`	Optional; `nullptr` uses default `AsyncOptions`
`operation`	Out `AsyncOp*`; caller `AsyncRelease`

Returns¶

Status	Meaning
`STATUS_SUCCESS`	Queued; completion tracked on `AsyncOp`
`STATUS_INVALID_PARAMETER`	Bad args
`STATUS_INVALID_DEVICE_REQUEST`	Not `PASSIVE_LEVEL`
`STATUS_INSUFFICIENT_RESOURCES`	Queue/alloc failure

Body / Headers pointers must live until complete or cancel.

AsyncOp¶

Signatures¶

NTSTATUS AsyncWait(_In_ AsyncOp* operation, ULONG timeoutMs) noexcept;
NTSTATUS AsyncCancel(_In_ AsyncOp* operation) noexcept;
NTSTATUS AsyncGetStatus(_In_opt_ const AsyncOp* operation) noexcept;
bool AsyncIsCompleted(_In_opt_ const AsyncOp* operation) noexcept;
bool AsyncIsCanceled(_In_opt_ const AsyncOp* operation) noexcept;
NTSTATUS AsyncGetResponse(_In_ AsyncOp* operation, _Out_ Response** response) noexcept;
void AsyncRelease(_In_opt_ AsyncOp* operation) noexcept;

Parameters / returns¶

API	Notes
`AsyncWait`	Wait up to `timeoutMs`; timeout returns a timeout status
`AsyncCancel`	Request cancellation
`AsyncGetStatus`	Last completion status
`AsyncIsCompleted` / `AsyncIsCanceled`	Flags; null → `false`
`AsyncGetResponse`	Take `Response*` ownership after successful completion
`AsyncRelease`	Free op; drops untaken response

Notes¶

Completion callbacks may run on worker threads; avoid long blocks or IRQL raises.
Call AsyncGetResponse once after successful completion.
WebSocket async connect shares AsyncOp; see AsyncGetWebSocket in WebSocket.

Destroy¶

// Lifecycle.h
void Destroy() noexcept;

Notes¶

Call on the driver unload path; waits for async workers and queues to finish before resources are released.
Call when Async* was used; sync-only paths may omit it.
Do not submit new async work after Destroy.

See also¶