private static bool EncodeHeaders(Http2HeadersEnumerator headersEnumerator, Span <byte> buffer, bool throwIfNoneEncoded, out int length)
{
var currentLength = 0;
do
{
if (!EncodeHeader(headersEnumerator.KnownHeaderType, headersEnumerator.Current.Key, headersEnumerator.Current.Value, buffer.Slice(currentLength), out int headerLength))
{
// The the header wasn't written and no headers have been written then the header is too large.
// Throw an error to avoid an infinite loop of attempting to write large header.
if (currentLength == 0 && throwIfNoneEncoded)
{
throw new HPackEncodingException(SR.net_http_hpack_encode_failure);
}
length = currentLength;
return(false);
}
currentLength += headerLength;
}while (headersEnumerator.MoveNext());
length = currentLength;
return(true);
}
/// <summary>
/// Begin encoding headers in the first HEADERS frame.
/// </summary>
public static bool BeginEncodeHeaders(Http2HeadersEnumerator headersEnumerator, Span <byte> buffer, out int length)
{
if (!headersEnumerator.MoveNext())
{
length = 0;
return(true);
}
return(EncodeHeaders(headersEnumerator, buffer, throwIfNoneEncoded: true, out length));
}
/// <summary>
/// Begin encoding headers in the first HEADERS frame.
/// </summary>
public static bool BeginEncodeHeaders(HPackEncoder hpackEncoder, Http2HeadersEnumerator headersEnumerator, Span <byte> buffer, out int length)
{
length = 0;
if (!hpackEncoder.EnsureDynamicTableSizeUpdate(buffer, out var sizeUpdateLength))
{
throw new HPackEncodingException(SR.net_http_hpack_encode_failure);
}
length += sizeUpdateLength;
if (!headersEnumerator.MoveNext())
{
return(true);
}
var done = EncodeHeadersCore(hpackEncoder, headersEnumerator, buffer.Slice(length), throwIfNoneEncoded: true, out var headersLength);
length += headersLength;
return(done);
}
private static bool EncodeHeadersCore(DynamicHPackEncoder hpackEncoder, Http2HeadersEnumerator headersEnumerator, Span <byte> buffer, bool throwIfNoneEncoded, out int length)
{
var currentLength = 0;
do
{
var staticTableId = headersEnumerator.HPackStaticTableId;
var name = headersEnumerator.Current.Key;
var value = headersEnumerator.Current.Value;
var valueEncoding =
ReferenceEquals(headersEnumerator.EncodingSelector, KestrelServerOptions.DefaultHeaderEncodingSelector)
? null : headersEnumerator.EncodingSelector(name);
var hint = ResolveHeaderEncodingHint(staticTableId, name);
if (!hpackEncoder.EncodeHeader(
buffer.Slice(currentLength),
staticTableId,
hint,
name,
value,
valueEncoding,
out var headerLength))
{
// If the header wasn't written, and no headers have been written, then the header is too large.
// Throw an error to avoid an infinite loop of attempting to write large header.
if (currentLength == 0 && throwIfNoneEncoded)
{
throw new HPackEncodingException(SR.net_http_hpack_encode_failure);
}
length = currentLength;
return(false);
}
currentLength += headerLength;
}while (headersEnumerator.MoveNext());
length = currentLength;
return(true);
}
/// <summary>
/// Begin encoding headers in the first HEADERS frame.
/// </summary>
public static bool BeginEncodeHeaders(int statusCode, Http2HeadersEnumerator headersEnumerator, Span <byte> buffer, out int length)
{
if (!HPackEncoder.EncodeStatusHeader(statusCode, buffer, out var statusCodeLength))
{
throw new HPackEncodingException(SR.net_http_hpack_encode_failure);
}
if (!headersEnumerator.MoveNext())
{
length = statusCodeLength;
return(true);
}
// We're ok with not throwing if no headers were encoded because we've already encoded the status.
// There is a small chance that the header will encode if there is no other content in the next HEADERS frame.
var done = EncodeHeaders(headersEnumerator, buffer.Slice(statusCodeLength), throwIfNoneEncoded: false, out var headersLength);
length = statusCodeLength + headersLength;
return(done);
}
/// <summary>
/// Continue encoding headers in the next HEADERS frame. The enumerator should already have a current value.
/// </summary>
public static bool ContinueEncodeHeaders(HPackEncoder hpackEncoder, Http2HeadersEnumerator headersEnumerator, Span <byte> buffer, out int length)
{
return(EncodeHeadersCore(hpackEncoder, headersEnumerator, buffer, throwIfNoneEncoded: true, out length));
}