Split net/spdy into core and chromium subdirectories.

net/spdy/spdy_framer.h

-// Copyright (c) 2012 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 NET_SPDY_SPDY_FRAMER_H_
-#define NET_SPDY_SPDY_FRAMER_H_
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include <cstdint>
-#include <map>
-#include <memory>
-#include <utility>
-
-#include "base/sys_byteorder.h"
-#include "net/base/net_export.h"
-#include "net/spdy/hpack/hpack_decoder_interface.h"
-#include "net/spdy/hpack/hpack_encoder.h"
-#include "net/spdy/platform/api/spdy_string.h"
-#include "net/spdy/platform/api/spdy_string_piece.h"
-#include "net/spdy/spdy_alt_svc_wire_format.h"
-#include "net/spdy/spdy_flags.h"
-#include "net/spdy/spdy_header_block.h"
-#include "net/spdy/spdy_headers_handler_interface.h"
-#include "net/spdy/spdy_protocol.h"
-#include "net/spdy/zero_copy_output_buffer.h"
-
-namespace net {
-
-class HttpProxyClientSocketPoolTest;
-class HttpNetworkLayer;
-class HttpNetworkTransactionTest;
-class SpdyHttpStreamTest;
-class SpdyNetworkTransactionTest;
-class SpdyProxyClientSocketTest;
-class SpdySessionTest;
-class SpdyStreamTest;
-
-class SpdyFramer;
-class SpdyFrameBuilder;
-class SpdyFramerDecoderAdapter;
-
-namespace test {
-
-class TestSpdyVisitor;
-class SpdyFramerPeer;
-
-}  // namespace test
-
-// SpdyFramerVisitorInterface is a set of callbacks for the SpdyFramer.
-// Implement this interface to receive event callbacks as frames are
-// decoded from the framer.
-//
-// Control frames that contain HTTP2 header blocks (HEADER, and PUSH_PROMISE)
-// are processed in fashion that allows the decompressed header block to be
-// delivered in chunks to the visitor.
-// The following steps are followed:
-//   1. OnHeaders, or OnPushPromise is called.
-//   2. OnHeaderFrameStart is called; visitor is expected to return an instance
-//      of SpdyHeadersHandlerInterface that will receive the header key-value
-//      pairs.
-//   3. OnHeaderFrameEnd is called, indicating that the full header block has
-//      been delivered for the control frame.
-// During step 2, if the visitor is not interested in accepting the header data,
-// it should return a no-op implementation of SpdyHeadersHandlerInterface.
-class NET_EXPORT_PRIVATE SpdyFramerVisitorInterface {
- public:
-  virtual ~SpdyFramerVisitorInterface() {}
-
-  // Called if an error is detected in the SpdySerializedFrame protocol.
-  virtual void OnError(SpdyFramer* framer) = 0;
-
-  // Called when the common header for a frame is received. Validating the
-  // common header occurs in later processing.
-  virtual void OnCommonHeader(SpdyStreamId stream_id,
-                              size_t length,
-                              uint8_t type,
-                              uint8_t flags) {}
-
-  // Called when a data frame header is received. The frame's data
-  // payload will be provided via subsequent calls to
-  // OnStreamFrameData().
-  virtual void OnDataFrameHeader(SpdyStreamId stream_id,
-                                 size_t length,
-                                 bool fin) = 0;
-
-  // Called when data is received.
-  // |stream_id| The stream receiving data.
-  // |data| A buffer containing the data received.
-  // |len| The length of the data buffer.
-  virtual void OnStreamFrameData(SpdyStreamId stream_id,
-                                 const char* data,
-                                 size_t len) = 0;
-
-  // Called when the other side has finished sending data on this stream.
-  // |stream_id| The stream that was receivin data.
-  virtual void OnStreamEnd(SpdyStreamId stream_id) = 0;
-
-  // Called when padding is received (padding length field or padding octets).
-  // |stream_id| The stream receiving data.
-  // |len| The number of padding octets.
-  virtual void OnStreamPadding(SpdyStreamId stream_id, size_t len) = 0;
-
-  // Called just before processing the payload of a frame containing header
-  // data. Should return an implementation of SpdyHeadersHandlerInterface that
-  // will receive headers for stream |stream_id|. The caller will not take
-  // ownership of the headers handler. The same instance should remain live
-  // and be returned for all header frames comprising a logical header block
-  // (i.e. until OnHeaderFrameEnd() is called with end_headers == true).
-  virtual SpdyHeadersHandlerInterface* OnHeaderFrameStart(
-      SpdyStreamId stream_id) = 0;
-
-  // Called after processing the payload of a frame containing header data.
-  // |end_headers| is true if there will not be any subsequent CONTINUATION
-  // frames.
-  virtual void OnHeaderFrameEnd(SpdyStreamId stream_id, bool end_headers) = 0;
-
-  // Called when a RST_STREAM frame has been parsed.
-  virtual void OnRstStream(SpdyStreamId stream_id,
-                           SpdyErrorCode error_code) = 0;
-
-  // Called when a SETTINGS frame is received.
-  // |clear_persisted| True if the respective flag is set on the SETTINGS frame.
-  virtual void OnSettings(bool clear_persisted) {}
-
-  // Called when a complete setting within a SETTINGS frame has been parsed and
-  // validated.
-  virtual void OnSetting(SpdySettingsIds id, uint32_t value) = 0;
-
-  // Called when a SETTINGS frame is received with the ACK flag set.
-  virtual void OnSettingsAck() {}
-
-  // Called before and after parsing SETTINGS id and value tuples.
-  virtual void OnSettingsEnd() = 0;
-
-  // Called when a PING frame has been parsed.
-  virtual void OnPing(SpdyPingId unique_id, bool is_ack) = 0;
-
-  // Called when a GOAWAY frame has been parsed.
-  virtual void OnGoAway(SpdyStreamId last_accepted_stream_id,
-                        SpdyErrorCode error_code) = 0;
-
-  // Called when a HEADERS frame is received.
-  // Note that header block data is not included. See OnHeaderFrameStart().
-  // |stream_id| The stream receiving the header.
-  // |has_priority| Whether or not the headers frame included a priority value,
-  //     and stream dependency info.
-  // |weight| If |has_priority| is true, then weight (in the range [1, 256])
-  //     for the receiving stream, otherwise 0.
-  // |parent_stream_id| If |has_priority| is true the parent stream of the
-  //     receiving stream, else 0.
-  // |exclusive| If |has_priority| is true the exclusivity of dependence on the
-  //     parent stream, else false.
-  // |fin| Whether FIN flag is set in frame headers.
-  // |end| False if HEADERs frame is to be followed by a CONTINUATION frame,
-  //     or true if not.
-  virtual void OnHeaders(SpdyStreamId stream_id,
-                         bool has_priority,
-                         int weight,
-                         SpdyStreamId parent_stream_id,
-                         bool exclusive,
-                         bool fin,
-                         bool end) = 0;
-
-  // Called when a WINDOW_UPDATE frame has been parsed.
-  virtual void OnWindowUpdate(SpdyStreamId stream_id,
-                              int delta_window_size) = 0;
-
-  // Called when a goaway frame opaque data is available.
-  // |goaway_data| A buffer containing the opaque GOAWAY data chunk received.
-  // |len| The length of the header data buffer. A length of zero indicates
-  //       that the header data block has been completely sent.
-  // When this function returns true the visitor indicates that it accepted
-  // all of the data. Returning false indicates that that an error has
-  // occurred while processing the data. Default implementation returns true.
-  virtual bool OnGoAwayFrameData(const char* goaway_data, size_t len);
-
-  // Called when a PUSH_PROMISE frame is received.
-  // Note that header block data is not included. See OnHeaderFrameStart().
-  virtual void OnPushPromise(SpdyStreamId stream_id,
-                             SpdyStreamId promised_stream_id,
-                             bool end) = 0;
-
-  // Called when a CONTINUATION frame is received.
-  // Note that header block data is not included. See OnHeaderFrameStart().
-  virtual void OnContinuation(SpdyStreamId stream_id, bool end) = 0;
-
-  // Called when an ALTSVC frame has been parsed.
-  virtual void OnAltSvc(
-      SpdyStreamId stream_id,
-      SpdyStringPiece origin,
-      const SpdyAltSvcWireFormat::AlternativeServiceVector& altsvc_vector) {}
-
-  // Called when a PRIORITY frame is received.
-  // |stream_id| The stream to update the priority of.
-  // |parent_stream_id| The parent stream of |stream_id|.
-  // |weight| Stream weight, in the range [1, 256].
-  // |exclusive| Whether |stream_id| should be an only child of
-  //     |parent_stream_id|.
-  virtual void OnPriority(SpdyStreamId stream_id,
-                          SpdyStreamId parent_stream_id,
-                          int weight,
-                          bool exclusive) {}
-
-  // Called when a frame type we don't recognize is received.
-  // Return true if this appears to be a valid extension frame, false otherwise.
-  // We distinguish between extension frames and nonsense by checking
-  // whether the stream id is valid.
-  virtual bool OnUnknownFrame(SpdyStreamId stream_id, uint8_t frame_type) = 0;
-};
-
-class SpdyFrameSequence {
- public:
-  virtual ~SpdyFrameSequence() {}
-
-  // Serializes the next frame in the sequence to |output|. Returns the number
-  // of bytes written to |output|.
-  virtual size_t NextFrame(ZeroCopyOutputBuffer* output) = 0;
-
-  // Returns true iff there is at least one more frame in the sequence.
-  virtual bool HasNextFrame() const = 0;
-};
-
-class ExtensionVisitorInterface {
- public:
-  virtual ~ExtensionVisitorInterface() {}
-
-  // Called when non-standard SETTINGS are received.
-  virtual void OnSetting(uint16_t id, uint32_t value) = 0;
-
-  // Called when non-standard frames are received.
-  virtual bool OnFrameHeader(SpdyStreamId stream_id,
-                             size_t length,
-                             uint8_t type,
-                             uint8_t flags) = 0;
-
-  // The payload for a single frame may be delivered as multiple calls to
-  // OnFramePayload. Since the length field is passed in OnFrameHeader, there is
-  // no explicit indication of the end of the frame payload.
-  virtual void OnFramePayload(const char* data, size_t len) = 0;
-};
-
-// Optionally, and in addition to SpdyFramerVisitorInterface, a class supporting
-// SpdyFramerDebugVisitorInterface may be used in conjunction with SpdyFramer in
-// order to extract debug/internal information about the SpdyFramer as it
-// operates.
-//
-// Most HTTP2 implementations need not bother with this interface at all.
-class NET_EXPORT_PRIVATE SpdyFramerDebugVisitorInterface {
- public:
-  virtual ~SpdyFramerDebugVisitorInterface() {}
-
-  // Called after compressing a frame with a payload of
-  // a list of name-value pairs.
-  // |payload_len| is the uncompressed payload size.
-  // |frame_len| is the compressed frame size.
-  virtual void OnSendCompressedFrame(SpdyStreamId stream_id,
-                                     SpdyFrameType type,
-                                     size_t payload_len,
-                                     size_t frame_len) {}
-
-  // Called when a frame containing a compressed payload of
-  // name-value pairs is received.
-  // |frame_len| is the compressed frame size.
-  virtual void OnReceiveCompressedFrame(SpdyStreamId stream_id,
-                                        SpdyFrameType type,
-                                        size_t frame_len) {}
-};
-
-class NET_EXPORT_PRIVATE SpdyFramer {
- public:
-  // HTTP2 states.
-  enum SpdyState {
-    SPDY_ERROR,
-    SPDY_READY_FOR_FRAME,  // Framer is ready for reading the next frame.
-    SPDY_FRAME_COMPLETE,  // Framer has finished reading a frame, need to reset.
-    SPDY_READING_COMMON_HEADER,
-    SPDY_CONTROL_FRAME_PAYLOAD,
-    SPDY_READ_DATA_FRAME_PADDING_LENGTH,
-    SPDY_CONSUME_PADDING,
-    SPDY_IGNORE_REMAINING_PAYLOAD,
-    SPDY_FORWARD_STREAM_FRAME,
-    SPDY_CONTROL_FRAME_BEFORE_HEADER_BLOCK,
-    SPDY_CONTROL_FRAME_HEADER_BLOCK,
-    SPDY_GOAWAY_FRAME_PAYLOAD,
-    SPDY_SETTINGS_FRAME_HEADER,
-    SPDY_SETTINGS_FRAME_PAYLOAD,
-    SPDY_ALTSVC_FRAME_PAYLOAD,
-    SPDY_EXTENSION_FRAME_PAYLOAD,
-  };
-
-  // Framer error codes.
-  enum SpdyFramerError {
-    SPDY_NO_ERROR,
-    SPDY_INVALID_STREAM_ID,            // Stream ID is invalid
-    SPDY_INVALID_CONTROL_FRAME,        // Control frame is mal-formatted.
-    SPDY_CONTROL_PAYLOAD_TOO_LARGE,    // Control frame payload was too large.
-    SPDY_ZLIB_INIT_FAILURE,            // The Zlib library could not initialize.
-    SPDY_UNSUPPORTED_VERSION,          // Control frame has unsupported version.
-    SPDY_DECOMPRESS_FAILURE,           // There was an error decompressing.
-    SPDY_COMPRESS_FAILURE,             // There was an error compressing.
-    SPDY_GOAWAY_FRAME_CORRUPT,         // GOAWAY frame could not be parsed.
-    SPDY_RST_STREAM_FRAME_CORRUPT,     // RST_STREAM frame could not be parsed.
-    SPDY_INVALID_PADDING,              // HEADERS or DATA frame padding invalid
-    SPDY_INVALID_DATA_FRAME_FLAGS,     // Data frame has invalid flags.
-    SPDY_INVALID_CONTROL_FRAME_FLAGS,  // Control frame has invalid flags.
-    SPDY_UNEXPECTED_FRAME,             // Frame received out of order.
-    SPDY_INTERNAL_FRAMER_ERROR,        // SpdyFramer was used incorrectly.
-    SPDY_INVALID_CONTROL_FRAME_SIZE,   // Control frame not sized to spec
-    SPDY_OVERSIZED_PAYLOAD,            // Payload size was too large
-
-    LAST_ERROR,  // Must be the last entry in the enum.
-  };
-
-  enum CompressionOption {
-    ENABLE_COMPRESSION,
-    DISABLE_COMPRESSION,
-  };
-
-  // Typedef for a function used to create SpdyFramerDecoderAdapter's.
-  // Defined in support of evaluating an alternate HTTP/2 decoder.
-  typedef std::unique_ptr<SpdyFramerDecoderAdapter> (*DecoderAdapterFactoryFn)(
-      SpdyFramer* outer);
-
-  // Constant for invalid (or unknown) stream IDs.
-  static const SpdyStreamId kInvalidStream;
-
-  // The maximum size of header data decompressed/delivered at once to the
-  // header block parser. (Exposed here for unit test purposes.)
-  static const size_t kHeaderDataChunkMaxSize;
-
-  void SerializeHeaderBlockWithoutCompression(
-      SpdyFrameBuilder* builder,
-      const SpdyHeaderBlock& header_block) const;
-
-  // Retrieve serialized length of SpdyHeaderBlock.
-  static size_t GetSerializedLength(const SpdyHeaderBlock* headers);
-
-  // Gets the serialized flags for the given |frame|.
-  static uint8_t GetSerializedFlags(const SpdyFrameIR& frame);
-
-  explicit SpdyFramer(CompressionOption option);
-
-  // Used recursively from the above constructor in order to support
-  // instantiating a SpdyFramerDecoderAdapter selected via flags or some other
-  // means.
-  SpdyFramer(DecoderAdapterFactoryFn adapter_factory, CompressionOption option);
-
-  virtual ~SpdyFramer();
-
-  // Set callbacks to be called from the framer.  A visitor must be set, or
-  // else the framer will likely crash.  It is acceptable for the visitor
-  // to do nothing.  If this is called multiple times, only the last visitor
-  // will be used.
-  void set_visitor(SpdyFramerVisitorInterface* visitor);
-
-  // Set extension callbacks to be called from the framer. (Optional.)
-  void set_extension_visitor(ExtensionVisitorInterface* extension);
-
-  // Set debug callbacks to be called from the framer. The debug visitor is
-  // completely optional and need not be set in order for normal operation.
-  // If this is called multiple times, only the last visitor will be used.
-  void set_debug_visitor(SpdyFramerDebugVisitorInterface* debug_visitor);
-
-  // Sets whether or not ProcessInput returns after finishing a frame, or
-  // continues processing additional frames. Normally ProcessInput processes
-  // all input, but this method enables the caller (and visitor) to work with
-  // a single frame at a time (or that portion of the frame which is provided
-  // as input). Reset() does not change the value of this flag.
-  void set_process_single_input_frame(bool v);
-
-  // Pass data into the framer for parsing.
-  // Returns the number of bytes consumed. It is safe to pass more bytes in
-  // than may be consumed.
-  size_t ProcessInput(const char* data, size_t len);
-
-  // Resets the framer state after a frame has been successfully decoded.
-  // TODO(mbelshe): can we make this private?
-  void Reset();
-
-  // Check the state of the framer.
-  SpdyFramerError spdy_framer_error() const;
-  SpdyState state() const;
-  bool HasError() const { return state() == SPDY_ERROR; }
-
-  // Given a buffer containing a serialized header block parse out a
-  // SpdyHeaderBlock, putting the results in the given header block.
-  // Returns true if successfully parsed, false otherwise.
-  bool ParseHeaderBlockInBuffer(const char* header_data,
-                                size_t header_length,
-                                SpdyHeaderBlock* block) const;
-
-  // Iteratively converts a SpdyFrameWithHeaderBlockIR into an appropriate
-  // sequence of SpdySerializedFrames.
-  class NET_EXPORT_PRIVATE SpdyFrameIterator {
-   public:
-    // Creates an iterator with the provided framer.
-    // Does not take ownership of |framer|.
-    // |framer| must outlive this instance.
-    explicit SpdyFrameIterator(SpdyFramer* framer);
-    virtual ~SpdyFrameIterator();
-
-    // Serializes the next frame in the sequence to |output|. Returns the number
-    // of bytes written to |output|.
-    virtual bool NextFrame(ZeroCopyOutputBuffer* output);
-
-    // Returns true iff there is at least one more frame in the sequence.
-    virtual bool HasNextFrame() const;
-
-    // SpdyFrameIterator is neither copyable nor movable.
-    SpdyFrameIterator(const SpdyFrameIterator&) = delete;
-    SpdyFrameIterator& operator=(const SpdyFrameIterator&) = delete;
-
-   protected:
-    virtual SpdyFrameWithHeaderBlockIR* GetIR() const = 0;
-    virtual size_t GetFrameSizeSansBlock() const = 0;
-    virtual bool SerializeGivenEncoding(const SpdyString& encoding,
-                                        ZeroCopyOutputBuffer* output) const = 0;
-
-    SpdyFramer* GetFramer() const { return framer_; }
-    void SetEncoder(SpdyFrameWithHeaderBlockIR* ir) {
-      encoder_ =
-          framer_->GetHpackEncoder()->EncodeHeaderSet(ir->header_block());
-    }
-
-   private:
-    SpdyFramer* const framer_;
-    std::unique_ptr<HpackEncoder::ProgressiveEncoder> encoder_;
-    bool is_first_frame_;
-    bool has_next_frame_;
-
-    // Field for debug reporting.
-    size_t debug_total_size_;
-  };
-
-  // Iteratively converts a SpdyHeadersIR (with a possibly huge
-  // SpdyHeaderBlock) into an appropriate sequence of SpdySerializedFrames, and
-  // write to the output.
-  class NET_EXPORT_PRIVATE SpdyHeaderFrameIterator : public SpdyFrameIterator {
-   public:
-    // Does not take ownership of |framer|. Take ownership of |headers_ir|.
-    SpdyHeaderFrameIterator(SpdyFramer* framer,
-                            std::unique_ptr<SpdyHeadersIR> headers_ir);
-
-    ~SpdyHeaderFrameIterator() override;
-
-   private:
-    SpdyFrameWithHeaderBlockIR* GetIR() const override;
-    size_t GetFrameSizeSansBlock() const override;
-    bool SerializeGivenEncoding(const SpdyString& encoding,
-                                ZeroCopyOutputBuffer* output) const override;
-
-    const std::unique_ptr<SpdyHeadersIR> headers_ir_;
-  };
-
-  // Iteratively converts a SpdyPushPromiseIR (with a possibly huge
-  // SpdyHeaderBlock) into an appropriate sequence of SpdySerializedFrames, and
-  // write to the output.
-  class NET_EXPORT_PRIVATE SpdyPushPromiseFrameIterator
-      : public SpdyFrameIterator {
-   public:
-    // Does not take ownership of |framer|. Take ownership of |push_promise_ir|.
-    SpdyPushPromiseFrameIterator(
-        SpdyFramer* framer,
-        std::unique_ptr<SpdyPushPromiseIR> push_promise_ir);
-
-    ~SpdyPushPromiseFrameIterator() override;
-
-   private:
-    SpdyFrameWithHeaderBlockIR* GetIR() const override;
-    size_t GetFrameSizeSansBlock() const override;
-    bool SerializeGivenEncoding(const SpdyString& encoding,
-                                ZeroCopyOutputBuffer* output) const override;
-
-    const std::unique_ptr<SpdyPushPromiseIR> push_promise_ir_;
-  };
-
-  // Serialize a data frame.
-  SpdySerializedFrame SerializeData(const SpdyDataIR& data) const;
-  // Serializes the data frame header and optionally padding length fields,
-  // excluding actual data payload and padding.
-  SpdySerializedFrame SerializeDataFrameHeaderWithPaddingLengthField(
-      const SpdyDataIR& data) const;
-
-  SpdySerializedFrame SerializeRstStream(
-      const SpdyRstStreamIR& rst_stream) const;
-
-  // Serializes a SETTINGS frame. The SETTINGS frame is
-  // used to communicate name/value pairs relevant to the communication channel.
-  SpdySerializedFrame SerializeSettings(const SpdySettingsIR& settings) const;
-
-  // Serializes a PING frame. The unique_id is used to
-  // identify the ping request/response.
-  SpdySerializedFrame SerializePing(const SpdyPingIR& ping) const;
-
-  // Serializes a GOAWAY frame. The GOAWAY frame is used
-  // prior to the shutting down of the TCP connection, and includes the
-  // stream_id of the last stream the sender of the frame is willing to process
-  // to completion.
-  SpdySerializedFrame SerializeGoAway(const SpdyGoAwayIR& goaway) const;
-
-  // Serializes a HEADERS frame. The HEADERS frame is used
-  // for sending headers.
-  SpdySerializedFrame SerializeHeaders(const SpdyHeadersIR& headers);
-
-  // Serializes a WINDOW_UPDATE frame. The WINDOW_UPDATE
-  // frame is used to implement per stream flow control.
-  SpdySerializedFrame SerializeWindowUpdate(
-      const SpdyWindowUpdateIR& window_update) const;
-
-  // Serializes a PUSH_PROMISE frame. The PUSH_PROMISE frame is used
-  // to inform the client that it will be receiving an additional stream
-  // in response to the original request. The frame includes synthesized
-  // headers to explain the upcoming data.
-  SpdySerializedFrame SerializePushPromise(
-      const SpdyPushPromiseIR& push_promise);
-
-  // Serializes a CONTINUATION frame. The CONTINUATION frame is used
-  // to continue a sequence of header block fragments.
-  SpdySerializedFrame SerializeContinuation(
-      const SpdyContinuationIR& continuation) const;
-
-  // Serializes an ALTSVC frame. The ALTSVC frame advertises the
-  // availability of an alternative service to the client.
-  SpdySerializedFrame SerializeAltSvc(const SpdyAltSvcIR& altsvc);
-
-  // Serializes a PRIORITY frame. The PRIORITY frame advises a change in
-  // the relative priority of the given stream.
-  SpdySerializedFrame SerializePriority(const SpdyPriorityIR& priority) const;
-
-  // Serialize a frame of unknown type.
-  SpdySerializedFrame SerializeFrame(const SpdyFrameIR& frame);
-
-  // Serialize a data frame.
-  bool SerializeData(const SpdyDataIR& data,
-                     ZeroCopyOutputBuffer* output) const;
-
-  // Serializes the data frame header and optionally padding length fields,
-  // excluding actual data payload and padding.
-  bool SerializeDataFrameHeaderWithPaddingLengthField(
-      const SpdyDataIR& data,
-      ZeroCopyOutputBuffer* output) const;
-
-  bool SerializeRstStream(const SpdyRstStreamIR& rst_stream,
-                          ZeroCopyOutputBuffer* output) const;
-
-  // Serializes a SETTINGS frame. The SETTINGS frame is
-  // used to communicate name/value pairs relevant to the communication channel.
-  bool SerializeSettings(const SpdySettingsIR& settings,
-                         ZeroCopyOutputBuffer* output) const;
-
-  // Serializes a PING frame. The unique_id is used to
-  // identify the ping request/response.
-  bool SerializePing(const SpdyPingIR& ping,
-                     ZeroCopyOutputBuffer* output) const;
-
-  // Serializes a GOAWAY frame. The GOAWAY frame is used
-  // prior to the shutting down of the TCP connection, and includes the
-  // stream_id of the last stream the sender of the frame is willing to process
-  // to completion.
-  bool SerializeGoAway(const SpdyGoAwayIR& goaway,
-                       ZeroCopyOutputBuffer* output) const;
-
-  // Serializes a HEADERS frame. The HEADERS frame is used
-  // for sending headers.
-  bool SerializeHeaders(const SpdyHeadersIR& headers,
-                        ZeroCopyOutputBuffer* output);
-
-  // Serializes a WINDOW_UPDATE frame. The WINDOW_UPDATE
-  // frame is used to implement per stream flow control.
-  bool SerializeWindowUpdate(const SpdyWindowUpdateIR& window_update,
-                             ZeroCopyOutputBuffer* output) const;
-
-  // Serializes a PUSH_PROMISE frame. The PUSH_PROMISE frame is used
-  // to inform the client that it will be receiving an additional stream
-  // in response to the original request. The frame includes synthesized
-  // headers to explain the upcoming data.
-  bool SerializePushPromise(const SpdyPushPromiseIR& push_promise,
-                            ZeroCopyOutputBuffer* output);
-
-  // Serializes a CONTINUATION frame. The CONTINUATION frame is used
-  // to continue a sequence of header block fragments.
-  bool SerializeContinuation(const SpdyContinuationIR& continuation,
-                             ZeroCopyOutputBuffer* output) const;
-
-  // Serializes an ALTSVC frame. The ALTSVC frame advertises the
-  // availability of an alternative service to the client.
-  bool SerializeAltSvc(const SpdyAltSvcIR& altsvc,
-                       ZeroCopyOutputBuffer* output);
-
-  // Serializes a PRIORITY frame. The PRIORITY frame advises a change in
-  // the relative priority of the given stream.
-  bool SerializePriority(const SpdyPriorityIR& priority,
-                         ZeroCopyOutputBuffer* output) const;
-
-  // Serialize a frame of unknown type.
-  bool SerializeFrame(const SpdyFrameIR& frame, ZeroCopyOutputBuffer* output);
-
-  // Returns whether this SpdyFramer will compress header blocks using HPACK.
-  bool compression_enabled() const {
-    return compression_option_ == ENABLE_COMPRESSION;
-  }
-
-  void SetHpackIndexingPolicy(HpackEncoder::IndexingPolicy policy) {
-    GetHpackEncoder()->SetIndexingPolicy(std::move(policy));
-  }
-
-  // Returns the (minimum) size of frames (sans variable-length portions).
-  size_t GetDataFrameMinimumSize() const;
-  size_t GetFrameHeaderSize() const;
-  size_t GetRstStreamSize() const;
-  size_t GetSettingsMinimumSize() const;
-  size_t GetPingSize() const;
-  size_t GetGoAwayMinimumSize() const;
-  size_t GetHeadersMinimumSize() const;
-  size_t GetWindowUpdateSize() const;
-  size_t GetPushPromiseMinimumSize() const;
-  size_t GetContinuationMinimumSize() const;
-  size_t GetAltSvcMinimumSize() const;
-  size_t GetPrioritySize() const;
-
-  // Returns the minimum size a frame can be (data or control).
-  size_t GetFrameMinimumSize() const;
-
-  // Returns the maximum size a frame can be (data or control).
-  size_t GetFrameMaximumSize() const;
-
-  // Returns the maximum payload size of a DATA frame.
-  size_t GetDataFrameMaximumPayload() const;
-
-  // For debugging.
-  static const char* StateToString(int state);
-  static const char* SpdyFramerErrorToString(SpdyFramerError spdy_framer_error);
-
-  // Did the most recent frame header appear to be an HTTP/1.x (or earlier)
-  // response (i.e. start with "HTTP/")?
-  bool probable_http_response() const;
-
-  SpdyPriority GetLowestPriority() const { return kV3LowestPriority; }
-
-  SpdyPriority GetHighestPriority() const { return kV3HighestPriority; }
-
-  // Updates the maximum size of the header encoder compression table.
-  void UpdateHeaderEncoderTableSize(uint32_t value);
-
-  // Updates the maximum size of the header decoder compression table.
-  void UpdateHeaderDecoderTableSize(uint32_t value);
-
-  // Returns the maximum size of the header encoder compression table.
-  size_t header_encoder_table_size() const;
-
-  void set_max_decode_buffer_size_bytes(size_t max_decode_buffer_size_bytes) {
-    GetHpackDecoder()->set_max_decode_buffer_size_bytes(
-        max_decode_buffer_size_bytes);
-  }
-
-  size_t send_frame_size_limit() const { return send_frame_size_limit_; }
-  void set_send_frame_size_limit(size_t send_frame_size_limit) {
-    send_frame_size_limit_ = send_frame_size_limit;
-  }
-
-  size_t recv_frame_size_limit() const { return recv_frame_size_limit_; }
-  void set_recv_frame_size_limit(size_t recv_frame_size_limit) {
-    recv_frame_size_limit_ = recv_frame_size_limit;
-  }
-
-  void SetDecoderHeaderTableDebugVisitor(
-      std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor);
-
-  void SetEncoderHeaderTableDebugVisitor(
-      std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor);
-
-  // For use in SpdyFramerDecoderAdapter implementations; returns a HPACK
-  // decoder to be used.
-  HpackDecoderInterface* GetHpackDecoderForAdapter() {
-    return GetHpackDecoder();
-  }
-
-  // Returns the estimate of dynamically allocated memory in bytes.
-  size_t EstimateMemoryUsage() const;
-
- protected:
-  friend class BufferedSpdyFramer;
-  friend class HttpNetworkLayer;  // This is temporary for the server.
-  friend class HttpNetworkTransactionTest;
-  friend class HttpProxyClientSocketPoolTest;
-  friend class SpdyHttpStreamTest;
-  friend class SpdyNetworkTransactionTest;
-  friend class SpdyProxyClientSocketTest;
-  friend class SpdySessionTest;
-  friend class SpdyStreamTest;
-  friend class test::TestSpdyVisitor;
-  friend class test::SpdyFramerPeer;
-
- private:
-  class CharBuffer {
-   public:
-    explicit CharBuffer(size_t capacity);
-    ~CharBuffer();
-
-    void CopyFrom(const char* data, size_t size);
-    void Rewind();
-
-    const char* data() const { return buffer_.get(); }
-    size_t len() const { return len_; }
-
-    size_t EstimateMemoryUsage() const;
-
-   private:
-    std::unique_ptr<char[]> buffer_;
-    size_t capacity_;
-    size_t len_;
-  };
-
-  // Scratch space necessary for processing SETTINGS frames.
-  struct SpdySettingsScratch {
-    SpdySettingsScratch();
-    void Reset();
-    size_t EstimateMemoryUsage() const;
-
-    // Buffer contains up to one complete key/value pair.
-    CharBuffer buffer;
-
-    // The ID of the last setting that was processed in the current SETTINGS
-    // frame. Used for detecting out-of-order or duplicate keys within a
-    // settings frame. Set to -1 before first key/value pair is processed.
-    int last_setting_id;
-  };
-
-  // Internal breakouts from ProcessInput. Each returns the number of bytes
-  // consumed from the data.
-  size_t ProcessCommonHeader(const char* data, size_t len);
-  size_t ProcessControlFramePayload(const char* data, size_t len);
-  size_t ProcessControlFrameBeforeHeaderBlock(const char* data, size_t len);
-  // HPACK data is re-encoded as SPDY3 and re-entrantly delivered through
-  // |ProcessControlFrameHeaderBlock()|. |is_hpack_header_block| controls
-  // whether data is treated as HPACK- vs SPDY3-encoded.
-  size_t ProcessControlFrameHeaderBlock(const char* data, size_t len);
-  size_t ProcessDataFramePaddingLength(const char* data, size_t len);
-  size_t ProcessFramePadding(const char* data, size_t len);
-  size_t ProcessDataFramePayload(const char* data, size_t len);
-  size_t ProcessGoAwayFramePayload(const char* data, size_t len);
-  size_t ProcessSettingsFrameHeader(const char* data, size_t len);
-  size_t ProcessSettingsFramePayload(const char* data, size_t len);
-  size_t ProcessAltSvcFramePayload(const char* data, size_t len);
-  size_t ProcessIgnoredControlFramePayload(/*const char* data,*/ size_t len);
-  size_t ProcessExtensionFramePayload(const char* data, size_t len);
-
-  // Validates the frame header against the current protocol, e.g.
-  // Frame type must be known, must specify a non-zero stream id.
-  //
-  // is_control_frame    : the control bit
-  // frame_type_field    : the unparsed frame type octet(s)
-  // payload_length_field: the stated length in octets of the frame payload
-  //
-  // For valid frames, returns the correct SpdyFrameType.
-  // Otherwise returns a best guess at invalid frame type,
-  // after setting the appropriate SpdyFramerError.
-  SpdyFrameType ValidateFrameHeader(bool is_control_frame,
-                                    uint8_t frame_type_field,
-                                    size_t payload_length_field);
-
-  // Helpers for above internal breakouts from ProcessInput.
-  void ProcessControlFrameHeader();
-  // Always passed exactly 1 setting's worth of data.
-  bool ProcessSetting(const char* data);
-
-  // Get (and lazily initialize) the HPACK state.
-  HpackEncoder* GetHpackEncoder();
-  HpackDecoderInterface* GetHpackDecoder();
-
-  size_t GetNumberRequiredContinuationFrames(size_t size);
-
-  bool WritePayloadWithContinuation(SpdyFrameBuilder* builder,
-                                    const SpdyString& hpack_encoding,
-                                    SpdyStreamId stream_id,
-                                    SpdyFrameType type,
-                                    int padding_payload_len);
-
-  // Utility to copy the given data block to the current frame buffer, up
-  // to the given maximum number of bytes, and update the buffer
-  // data (pointer and length). Returns the number of bytes
-  // read, and:
-  //   *data is advanced the number of bytes read.
-  //   *len is reduced by the number of bytes read.
-  size_t UpdateCurrentFrameBuffer(const char** data, size_t* len,
-                                  size_t max_bytes);
-
-  // Serializes a HEADERS frame from the given SpdyHeadersIR and encoded header
-  // block. Does not need or use the SpdyHeaderBlock inside SpdyHeadersIR.
-  // Return false if the serialization fails. |encoding| should not be empty.
-  bool SerializeHeadersGivenEncoding(const SpdyHeadersIR& headers,
-                                     const SpdyString& encoding,
-                                     ZeroCopyOutputBuffer* output) const;
-
-  // Serializes a PUSH_PROMISE frame from the given SpdyPushPromiseIR and
-  // encoded header block. Does not need or use the SpdyHeaderBlock inside
-  // SpdyHeadersIR.
-  bool SerializePushPromiseGivenEncoding(const SpdyPushPromiseIR& push_promise,
-                                         const SpdyString& encoding,
-                                         ZeroCopyOutputBuffer* output) const;
-
-  // Calculates the number of bytes required to serialize a SpdyHeadersIR, not
-  // including the bytes to be used for the encoded header set.
-  size_t GetHeaderFrameSizeSansBlock(const SpdyHeadersIR& header_ir) const;
-
-  // Calculates the number of bytes required to serialize a SpdyPushPromiseIR,
-  // not including the bytes to be used for the encoded header set.
-  size_t GetPushPromiseFrameSizeSansBlock(
-      const SpdyPushPromiseIR& push_promise_ir) const;
-
-  // Serializes the flags octet for a given SpdyHeadersIR.
-  uint8_t SerializeHeaderFrameFlags(const SpdyHeadersIR& header_ir) const;
-
-  // Serializes the flags octet for a given SpdyPushPromiseIR.
-  uint8_t SerializePushPromiseFrameFlags(
-      const SpdyPushPromiseIR& push_promise_ir) const;
-
-  // Set the error code and moves the framer into the error state.
-  void set_error(SpdyFramerError error);
-
-  // Helper functions to prepare the input for SpdyFrameBuilder.
-  void SerializeDataBuilderHelper(const SpdyDataIR& data_ir,
-                                  uint8_t* flags,
-                                  int* num_padding_fields,
-                                  size_t* size_with_padding) const;
-  void SerializeDataFrameHeaderWithPaddingLengthFieldBuilderHelper(
-      const SpdyDataIR& data_ir,
-      uint8_t* flags,
-      size_t* frame_size,
-      size_t* num_padding_fields) const;
-  void SerializeSettingsBuilderHelper(const SpdySettingsIR& settings,
-                                      uint8_t* flags,
-                                      const SettingsMap* values,
-                                      size_t* size) const;
-  void SerializeAltSvcBuilderHelper(const SpdyAltSvcIR& altsvc_ir,
-                                    SpdyString* value,
-                                    size_t* size) const;
-  void SerializeHeadersBuilderHelper(const SpdyHeadersIR& headers,
-                                     uint8_t* flags,
-                                     size_t* size,
-                                     SpdyString* hpack_encoding,
-                                     int* weight,
-                                     size_t* length_field);
-  void SerializePushPromiseBuilderHelper(const SpdyPushPromiseIR& push_promise,
-                                         uint8_t* flags,
-                                         SpdyString* hpack_encoding,
-                                         size_t* size);
-
-  // The size of the control frame buffer.
-  // Since this is only used for control frame headers, the maximum control
-  // frame header size is sufficient; all remaining control
-  // frame data is streamed to the visitor.
-  static const size_t kControlFrameBufferSize;
-
-  // The maximum size of the control frames that we send, including the size of
-  // the header. This limit is arbitrary. We can enforce it here or at the
-  // application layer. We chose the framing layer, but this can be changed (or
-  // removed) if necessary later down the line.
-  // TODO(diannahu): Rename to make it clear that this limit is for sending.
-  static const size_t kMaxControlFrameSize;
-  // The maximum size for the payload of DATA frames to send.
-  static const size_t kMaxDataPayloadSendSize;
-  // The size of one parameter in SETTINGS frame.
-  static const size_t kOneSettingParameterSize;
-
-  SpdyState state_;
-  SpdyState previous_state_;
-  SpdyFramerError spdy_framer_error_;
-
-  // Note that for DATA frame, remaining_data_length_ is sum of lengths of
-  // frame header, padding length field (optional), data payload (optional) and
-  // padding payload (optional).
-  size_t remaining_data_length_;
-
-  // The length (in bytes) of the padding payload to be processed.
-  size_t remaining_padding_payload_length_;
-
-  // The number of bytes remaining to read from the current control frame's
-  // headers. Note that header data blocks (for control types that have them)
-  // are part of the frame's payload, and not the frame's headers.
-  size_t remaining_control_header_;
-
-  // The limit on the size of sent HTTP/2 payloads as specified in the
-  // SETTINGS_MAX_FRAME_SIZE received from peer.
-  size_t send_frame_size_limit_ = kSpdyInitialFrameSizeLimit;
-
-  // The limit on the size of received HTTP/2 payloads as specified in the
-  // SETTINGS_MAX_FRAME_SIZE advertised to peer.
-  size_t recv_frame_size_limit_ = kSpdyInitialFrameSizeLimit;
-
-  CharBuffer current_frame_buffer_;
-
-  // The type of the frame currently being read.
-  SpdyFrameType current_frame_type_;
-
-  // The total length of the frame currently being read, including frame header.
-  uint32_t current_frame_length_;
-
-  // The stream ID field of the frame currently being read, if applicable.
-  SpdyStreamId current_frame_stream_id_;
-
-  // Set this to the current stream when we receive a HEADERS, PUSH_PROMISE, or
-  // CONTINUATION frame without the END_HEADERS(0x4) bit set. These frames must
-  // be followed by a CONTINUATION frame, or else we throw a PROTOCOL_ERROR.
-  // A value of 0 indicates that we are not expecting a CONTINUATION frame.
-  SpdyStreamId expect_continuation_;
-
-  // Scratch space for handling SETTINGS frames.
-  // TODO(hkhalil): Unify memory for this scratch space with
-  // current_frame_buffer_.
-  SpdySettingsScratch settings_scratch_;
-
-  std::unique_ptr<CharBuffer> altsvc_scratch_;
-
-  std::unique_ptr<HpackEncoder> hpack_encoder_;
-  std::unique_ptr<HpackDecoderInterface> hpack_decoder_;
-
-  SpdyFramerVisitorInterface* visitor_;
-  ExtensionVisitorInterface* extension_;
-  SpdyFramerDebugVisitorInterface* debug_visitor_;
-
-  SpdyHeadersHandlerInterface* header_handler_;
-
-  // Optional decoder to use instead of this instance.
-  std::unique_ptr<SpdyFramerDecoderAdapter> decoder_adapter_;
-
-  // The flags field of the frame currently being read.
-  uint8_t current_frame_flags_;
-
-  // Determines whether HPACK compression is used.
-  const CompressionOption compression_option_;
-
-  // On the first read, we check to see if the data starts with HTTP.
-  // If it does, we likely have an HTTP response.   This isn't guaranteed
-  // though: we could have gotten a settings frame and then corrupt data that
-  // just looks like HTTP, but deterministic checking requires a lot more state.
-  bool probable_http_response_;
-
-  // If a HEADERS frame is followed by a CONTINUATION frame, the FIN/END_STREAM
-  // flag is still carried in the HEADERS frame. If it's set, flip this so that
-  // we know to terminate the stream when the entire header block has been
-  // processed.
-  bool end_stream_when_done_;
-
-  // If true, then ProcessInput returns after processing a full frame,
-  // rather than reading all available input.
-  bool process_single_input_frame_ = false;
-
-  // Latched value of FLAGS_chromium_http2_flag_remove_rewritelength.
-  bool skip_rewritelength_ = false;
-};
-
-}  // namespace net
-
-#endif  // NET_SPDY_SPDY_FRAMER_H_