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// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Functions supporting the encoding of strings using the HPACK-defined Huffman
// table.
#include <cstddef> // For size_t
#include "net/third_party/quiche/src/http2/platform/api/http2_export.h"
#include "net/third_party/quiche/src/http2/platform/api/http2_string.h"
#include "net/third_party/quiche/src/http2/platform/api/http2_string_piece.h"
namespace http2 {
// Returns the size of the Huffman encoding of |plain|, which may be greater
// than plain.size(). Mostly present for testing.
HTTP2_EXPORT_PRIVATE size_t ExactHuffmanSize(Http2StringPiece plain);
// Returns the size of the Huffman encoding of |plain|, unless it is greater
// than or equal to plain.size(), in which case a value greater than or equal to
// plain.size() is returned. The advantage of this over ExactHuffmanSize is that
// it doesn't read as much of the input string in the event that the string is
// not compressible by HuffmanEncode (i.e. when the encoding is longer than the
// original string, it stops reading the input string as soon as it knows that).
HTTP2_EXPORT_PRIVATE size_t BoundedHuffmanSize(Http2StringPiece plain);
// Encode the plain text string |plain| with the Huffman encoding defined in
// the HPACK RFC, 7541. |*huffman| does not have to be empty, it is cleared at
// the beginning of this function. This allows reusing the same string object
// across multiple invocations.
HTTP2_EXPORT_PRIVATE void HuffmanEncode(Http2StringPiece plain,
Http2String* huffman);
} // namespace http2