pub unsafe extern "C" fn nghttp2_session_upgrade(
    session: *mut nghttp2_session,
    settings_payload: *const u8,
    settings_payloadlen: usize,
    stream_user_data: *mut c_void
) -> c_int
Expand description

@function

Performs post-process of HTTP Upgrade request. This function can be called from both client and server, but the behavior is very different in each other.

.. warning::

This function is deprecated in favor of nghttp2_session_upgrade2(), because this function lacks the parameter to tell the library the request method used in the original HTTP request. This information is required for client to validate actual response body length against content-length header field (see nghttp2_option_set_no_http_messaging()). If HEAD is used in request, the length of response body must be 0 regardless of value included in content-length header field.

If called from client side, the |settings_payload| must be the value sent in HTTP2-Settings header field and must be decoded by base64url decoder. The |settings_payloadlen| is the length of |settings_payload|. The |settings_payload| is unpacked and its setting values will be submitted using nghttp2_submit_settings(). This means that the client application code does not need to submit SETTINGS by itself. The stream with stream ID=1 is opened and the |stream_user_data| is used for its stream_user_data. The opened stream becomes half-closed (local) state.

If called from server side, the |settings_payload| must be the value received in HTTP2-Settings header field and must be decoded by base64url decoder. The |settings_payloadlen| is the length of |settings_payload|. It is treated as if the SETTINGS frame with that payload is received. Thus, callback functions for the reception of SETTINGS frame will be invoked. The stream with stream ID=1 is opened. The |stream_user_data| is ignored. The opened stream becomes half-closed (remote).

This function returns 0 if it succeeds, or one of the following negative error codes:

:enum:NGHTTP2_ERR_NOMEM Out of memory. :enum:NGHTTP2_ERR_INVALID_ARGUMENT The |settings_payload| is badly formed. :enum:NGHTTP2_ERR_PROTO The stream ID 1 is already used or closed; or is not available.