Function libnghttp2_sys::nghttp2_submit_data

pub unsafe extern "C" fn nghttp2_submit_data(
    session: *mut nghttp2_session, 
    flags: u8, 
    stream_id: i32, 
    data_prd: *const nghttp2_data_provider
) -> c_int

@function

Submits one or more DATA frames to the stream |stream_id|. The data to be sent are provided by |data_prd|. If |flags| contains :enum:NGHTTP2_FLAG_END_STREAM, the last DATA frame has END_STREAM flag set.

This function does not take ownership of the |data_prd|. The function copies the members of the |data_prd|.

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_DATA_EXIST DATA or HEADERS has been already submitted and not fully processed yet. :enum:NGHTTP2_ERR_INVALID_ARGUMENT The |stream_id| is 0. :enum:NGHTTP2_ERR_STREAM_CLOSED The stream was already closed; or the |stream_id| is invalid.

.. note::

Currently, only one DATA or HEADERS is allowed for a stream at a time. Submitting these frames more than once before first DATA or HEADERS is finished results in :enum:NGHTTP2_ERR_DATA_EXIST error code. The earliest callback which tells that previous frame is done is :type:nghttp2_on_frame_send_callback. In side that callback, new data can be submitted using nghttp2_submit_data(). Of course, all data except for last one must not have :enum:NGHTTP2_FLAG_END_STREAM flag set in |flags|. This sounds a bit complicated, and we recommend to use nghttp2_submit_request() and nghttp2_submit_response() to avoid this cascading issue. The experience shows that for HTTP use, these two functions are enough to implement both client and server.