chromium/net/third_party/quiche/src/quiche/quic/core/qpack/qpack_instructions.h

// Copyright (c) 2018 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.

#ifndef QUICHE_QUIC_CORE_QPACK_QPACK_INSTRUCTIONS_H_
#define QUICHE_QUIC_CORE_QPACK_QPACK_INSTRUCTIONS_H_

#include <cstdint>
#include <string>
#include <tuple>
#include <vector>

#include "absl/strings/string_view.h"
#include "quiche/quic/platform/api/quic_export.h"

namespace quic {

namespace test {
class QpackInstructionWithValuesPeer;
}  // namespace test

// Each instruction is identified with an opcode in the first byte.
// |mask| determines which bits are part of the opcode.
// |value| is the value of these bits.  (Other bits in value must be zero.)
struct QUICHE_EXPORT QpackInstructionOpcode { … };

bool operator==(const QpackInstructionOpcode& a,
                const QpackInstructionOpcode& b);

// Possible types of an instruction field.  Decoding a static bit does not
// consume the current byte.  Decoding an integer or a length-prefixed string
// literal consumes all bytes containing the field value.
enum class QpackInstructionFieldType { … };

// Each instruction field has a type and a parameter.
// The meaning of the parameter depends on the field type.
struct QUICHE_EXPORT QpackInstructionField { … };

QpackInstructionFields;

// A QPACK instruction consists of an opcode identifying the instruction,
// followed by a non-empty list of fields.  The last field must be integer or
// string literal type to guarantee that all bytes of the instruction are
// consumed.
struct QUICHE_EXPORT QpackInstruction { … };

// A language is a collection of instructions.  The order does not matter.
// Every possible input must match exactly one instruction.
QpackLanguage;

// Wire format defined in
// https://rfc-editor.org/rfc/rfc9204.html#section-4

// 5.2 Encoder stream instructions

// 5.2.1 Insert With Name Reference
const QpackInstruction* InsertWithNameReferenceInstruction();

// 5.2.2 Insert Without Name Reference
const QpackInstruction* InsertWithoutNameReferenceInstruction();

// 5.2.3 Duplicate
const QpackInstruction* DuplicateInstruction();

// 5.2.4 Dynamic Table Size Update
const QpackInstruction* SetDynamicTableCapacityInstruction();

// Encoder stream language.
const QpackLanguage* QpackEncoderStreamLanguage();

// 5.3 Decoder stream instructions

// 5.3.1 Insert Count Increment
const QpackInstruction* InsertCountIncrementInstruction();

// 5.3.2 Header Acknowledgement
const QpackInstruction* HeaderAcknowledgementInstruction();

// 5.3.3 Stream Cancellation
const QpackInstruction* StreamCancellationInstruction();

// Decoder stream language.
const QpackLanguage* QpackDecoderStreamLanguage();

// 5.4.1. Header data prefix instructions

const QpackInstruction* QpackPrefixInstruction();

const QpackLanguage* QpackPrefixLanguage();

// 5.4.2. Request and push stream instructions

// 5.4.2.1. Indexed Header Field
const QpackInstruction* QpackIndexedHeaderFieldInstruction();

// 5.4.2.2. Indexed Header Field With Post-Base Index
const QpackInstruction* QpackIndexedHeaderFieldPostBaseInstruction();

// 5.4.2.3. Literal Header Field With Name Reference
const QpackInstruction* QpackLiteralHeaderFieldNameReferenceInstruction();

// 5.4.2.4. Literal Header Field With Post-Base Name Reference
const QpackInstruction* QpackLiteralHeaderFieldPostBaseInstruction();

// 5.4.2.5. Literal Header Field Without Name Reference
const QpackInstruction* QpackLiteralHeaderFieldInstruction();

// Request and push stream language.
const QpackLanguage* QpackRequestStreamLanguage();

// Storage for instruction and field values to be encoded.
// This class can only be instantiated using factory methods that take exactly
// the arguments that the corresponding instruction needs.
class QUICHE_EXPORT QpackInstructionWithValues { … };

}  // namespace quic

#endif  // QUICHE_QUIC_CORE_QPACK_QPACK_INSTRUCTIONS_H_