Function libnghttp2_sys::nghttp2_pack_settings_payload

pub unsafe extern "C" fn nghttp2_pack_settings_payload(
    buf: *mut u8, 
    buflen: usize, 
    iv: *const nghttp2_settings_entry, 
    niv: usize
) -> isize

@function

Serializes the SETTINGS values |iv| in the |buf|. The size of the |buf| is specified by |buflen|. The number of entries in the |iv| array is given by |niv|. The required space in |buf| for the |niv| entries is 6*niv bytes and if the given buffer is too small, an error is returned. This function is used mainly for creating a SETTINGS payload to be sent with the HTTP2-Settings header field in an HTTP Upgrade request. The data written in |buf| is NOT base64url encoded and the application is responsible for encoding.

This function returns the number of bytes written in |buf|, or one of the following negative error codes:

:enum:NGHTTP2_ERR_INVALID_ARGUMENT The |iv| contains duplicate settings ID or invalid value.

:enum:NGHTTP2_ERR_INSUFF_BUFSIZE The provided |buflen| size is too small to hold the output.