Remove //net (except for Android test stuff) and sdch

net/socket/socket_test_util.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_SOCKET_SOCKET_TEST_UTIL_H_
-#define NET_SOCKET_SOCKET_TEST_UTIL_H_
-
-#include <cstring>
-#include <deque>
-#include <string>
-#include <vector>
-
-#include "base/basictypes.h"
-#include "base/callback.h"
-#include "base/logging.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/memory/scoped_vector.h"
-#include "base/memory/weak_ptr.h"
-#include "base/strings/string16.h"
-#include "base/time/time.h"
-#include "net/base/address_list.h"
-#include "net/base/io_buffer.h"
-#include "net/base/net_errors.h"
-#include "net/base/net_log.h"
-#include "net/base/test_completion_callback.h"
-#include "net/http/http_auth_controller.h"
-#include "net/http/http_proxy_client_socket_pool.h"
-#include "net/socket/client_socket_factory.h"
-#include "net/socket/client_socket_handle.h"
-#include "net/socket/socks_client_socket_pool.h"
-#include "net/socket/ssl_client_socket.h"
-#include "net/socket/ssl_client_socket_pool.h"
-#include "net/socket/transport_client_socket_pool.h"
-#include "net/ssl/ssl_config_service.h"
-#include "net/udp/datagram_client_socket.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace net {
-
-enum {
-  // A private network error code used by the socket test utility classes.
-  // If the |result| member of a MockRead is
-  // ERR_TEST_PEER_CLOSE_AFTER_NEXT_MOCK_READ, that MockRead is just a
-  // marker that indicates the peer will close the connection after the next
-  // MockRead.  The other members of that MockRead are ignored.
-  ERR_TEST_PEER_CLOSE_AFTER_NEXT_MOCK_READ = -10000,
-};
-
-class AsyncSocket;
-class ChannelIDService;
-class MockClientSocket;
-class SSLClientSocket;
-class StreamSocket;
-
-enum IoMode {
-  ASYNC,
-  SYNCHRONOUS
-};
-
-struct MockConnect {
-  // Asynchronous connection success.
-  // Creates a MockConnect with |mode| ASYC, |result| OK, and
-  // |peer_addr| 192.0.2.33.
-  MockConnect();
-  // Creates a MockConnect with the specified mode and result, with
-  // |peer_addr| 192.0.2.33.
-  MockConnect(IoMode io_mode, int r);
-  MockConnect(IoMode io_mode, int r, IPEndPoint addr);
-  ~MockConnect();
-
-  IoMode mode;
-  int result;
-  IPEndPoint peer_addr;
-};
-
-// MockRead and MockWrite shares the same interface and members, but we'd like
-// to have distinct types because we don't want to have them used
-// interchangably. To do this, a struct template is defined, and MockRead and
-// MockWrite are instantiated by using this template. Template parameter |type|
-// is not used in the struct definition (it purely exists for creating a new
-// type).
-//
-// |data| in MockRead and MockWrite has different meanings: |data| in MockRead
-// is the data returned from the socket when MockTCPClientSocket::Read() is
-// attempted, while |data| in MockWrite is the expected data that should be
-// given in MockTCPClientSocket::Write().
-enum MockReadWriteType {
-  MOCK_READ,
-  MOCK_WRITE
-};
-
-template <MockReadWriteType type>
-struct MockReadWrite {
-  // Flag to indicate that the message loop should be terminated.
-  enum {
-    STOPLOOP = 1 << 31
-  };
-
-  // Default
-  MockReadWrite()
-      : mode(SYNCHRONOUS),
-        result(0),
-        data(NULL),
-        data_len(0),
-        sequence_number(0),
-        time_stamp(base::Time::Now()) {}
-
-  // Read/write failure (no data).
-  MockReadWrite(IoMode io_mode, int result)
-      : mode(io_mode),
-        result(result),
-        data(NULL),
-        data_len(0),
-        sequence_number(0),
-        time_stamp(base::Time::Now()) {}
-
-  // Read/write failure (no data), with sequence information.
-  MockReadWrite(IoMode io_mode, int result, int seq)
-      : mode(io_mode),
-        result(result),
-        data(NULL),
-        data_len(0),
-        sequence_number(seq),
-        time_stamp(base::Time::Now()) {}
-
-  // Asynchronous read/write success (inferred data length).
-  explicit MockReadWrite(const char* data)
-      : mode(ASYNC),
-        result(0),
-        data(data),
-        data_len(strlen(data)),
-        sequence_number(0),
-        time_stamp(base::Time::Now()) {}
-
-  // Read/write success (inferred data length).
-  MockReadWrite(IoMode io_mode, const char* data)
-      : mode(io_mode),
-        result(0),
-        data(data),
-        data_len(strlen(data)),
-        sequence_number(0),
-        time_stamp(base::Time::Now()) {}
-
-  // Read/write success.
-  MockReadWrite(IoMode io_mode, const char* data, int data_len)
-      : mode(io_mode),
-        result(0),
-        data(data),
-        data_len(data_len),
-        sequence_number(0),
-        time_stamp(base::Time::Now()) {}
-
-  // Read/write success (inferred data length) with sequence information.
-  MockReadWrite(IoMode io_mode, int seq, const char* data)
-      : mode(io_mode),
-        result(0),
-        data(data),
-        data_len(strlen(data)),
-        sequence_number(seq),
-        time_stamp(base::Time::Now()) {}
-
-  // Read/write success with sequence information.
-  MockReadWrite(IoMode io_mode, const char* data, int data_len, int seq)
-      : mode(io_mode),
-        result(0),
-        data(data),
-        data_len(data_len),
-        sequence_number(seq),
-        time_stamp(base::Time::Now()) {}
-
-  IoMode mode;
-  int result;
-  const char* data;
-  int data_len;
-
-  // For OrderedSocketData, which only allows reads to occur in a particular
-  // sequence.  If a read occurs before the given |sequence_number| is reached,
-  // an ERR_IO_PENDING is returned.
-  int sequence_number;    // The sequence number at which a read is allowed
-                          // to occur.
-  base::Time time_stamp;  // The time stamp at which the operation occurred.
-};
-
-typedef MockReadWrite<MOCK_READ> MockRead;
-typedef MockReadWrite<MOCK_WRITE> MockWrite;
-
-struct MockWriteResult {
-  MockWriteResult(IoMode io_mode, int result) : mode(io_mode), result(result) {}
-
-  IoMode mode;
-  int result;
-};
-
-// The SocketDataProvider is an interface used by the MockClientSocket
-// for getting data about individual reads and writes on the socket.
-class SocketDataProvider {
- public:
-  SocketDataProvider() : socket_(NULL) {}
-
-  virtual ~SocketDataProvider() {}
-
-  // Returns the buffer and result code for the next simulated read.
-  // If the |MockRead.result| is ERR_IO_PENDING, it informs the caller
-  // that it will be called via the AsyncSocket::OnReadComplete()
-  // function at a later time.
-  virtual MockRead GetNextRead() = 0;
-  virtual MockWriteResult OnWrite(const std::string& data) = 0;
-  virtual void Reset() = 0;
-
-  // Accessor for the socket which is using the SocketDataProvider.
-  AsyncSocket* socket() { return socket_; }
-  void set_socket(AsyncSocket* socket) { socket_ = socket; }
-
-  MockConnect connect_data() const { return connect_; }
-  void set_connect_data(const MockConnect& connect) { connect_ = connect; }
-
- private:
-  MockConnect connect_;
-  AsyncSocket* socket_;
-
-  DISALLOW_COPY_AND_ASSIGN(SocketDataProvider);
-};
-
-// The AsyncSocket is an interface used by the SocketDataProvider to
-// complete the asynchronous read operation.
-class AsyncSocket {
- public:
-  // If an async IO is pending because the SocketDataProvider returned
-  // ERR_IO_PENDING, then the AsyncSocket waits until this OnReadComplete
-  // is called to complete the asynchronous read operation.
-  // data.async is ignored, and this read is completed synchronously as
-  // part of this call.
-  virtual void OnReadComplete(const MockRead& data) = 0;
-  virtual void OnConnectComplete(const MockConnect& data) = 0;
-};
-
-// SocketDataProvider which responds based on static tables of mock reads and
-// writes.
-class StaticSocketDataProvider : public SocketDataProvider {
- public:
-  StaticSocketDataProvider();
-  StaticSocketDataProvider(MockRead* reads,
-                           size_t reads_count,
-                           MockWrite* writes,
-                           size_t writes_count);
-  ~StaticSocketDataProvider() override;
-
-  // These functions get access to the next available read and write data.
-  const MockRead& PeekRead() const;
-  const MockWrite& PeekWrite() const;
-  // These functions get random access to the read and write data, for timing.
-  const MockRead& PeekRead(size_t index) const;
-  const MockWrite& PeekWrite(size_t index) const;
-  size_t read_index() const { return read_index_; }
-  size_t write_index() const { return write_index_; }
-  size_t read_count() const { return read_count_; }
-  size_t write_count() const { return write_count_; }
-
-  bool at_read_eof() const { return read_index_ >= read_count_; }
-  bool at_write_eof() const { return write_index_ >= write_count_; }
-
-  virtual void CompleteRead() {}
-
-  // SocketDataProvider implementation.
-  MockRead GetNextRead() override;
-  MockWriteResult OnWrite(const std::string& data) override;
-  void Reset() override;
-
- private:
-  MockRead* reads_;
-  size_t read_index_;
-  size_t read_count_;
-  MockWrite* writes_;
-  size_t write_index_;
-  size_t write_count_;
-
-  DISALLOW_COPY_AND_ASSIGN(StaticSocketDataProvider);
-};
-
-// SocketDataProvider which can make decisions about next mock reads based on
-// received writes. It can also be used to enforce order of operations, for
-// example that tested code must send the "Hello!" message before receiving
-// response. This is useful for testing conversation-like protocols like FTP.
-class DynamicSocketDataProvider : public SocketDataProvider {
- public:
-  DynamicSocketDataProvider();
-  ~DynamicSocketDataProvider() override;
-
-  int short_read_limit() const { return short_read_limit_; }
-  void set_short_read_limit(int limit) { short_read_limit_ = limit; }
-
-  void allow_unconsumed_reads(bool allow) { allow_unconsumed_reads_ = allow; }
-
-  // SocketDataProvider implementation.
-  MockRead GetNextRead() override;
-  MockWriteResult OnWrite(const std::string& data) override = 0;
-  void Reset() override;
-
- protected:
-  // The next time there is a read from this socket, it will return |data|.
-  // Before calling SimulateRead next time, the previous data must be consumed.
-  void SimulateRead(const char* data, size_t length);
-  void SimulateRead(const char* data) { SimulateRead(data, std::strlen(data)); }
-
- private:
-  std::deque<MockRead> reads_;
-
-  // Max number of bytes we will read at a time. 0 means no limit.
-  int short_read_limit_;
-
-  // If true, we'll not require the client to consume all data before we
-  // mock the next read.
-  bool allow_unconsumed_reads_;
-
-  DISALLOW_COPY_AND_ASSIGN(DynamicSocketDataProvider);
-};
-
-// SSLSocketDataProviders only need to keep track of the return code from calls
-// to Connect().
-struct SSLSocketDataProvider {
-  SSLSocketDataProvider(IoMode mode, int result);
-  ~SSLSocketDataProvider();
-
-  void SetNextProto(NextProto proto);
-
-  MockConnect connect;
-  SSLClientSocket::NextProtoStatus next_proto_status;
-  std::string next_proto;
-  bool was_npn_negotiated;
-  NextProto protocol_negotiated;
-  NextProtoVector next_protos_expected_in_ssl_config;
-  bool client_cert_sent;
-  SSLCertRequestInfo* cert_request_info;
-  scoped_refptr<X509Certificate> cert;
-  bool channel_id_sent;
-  ChannelIDService* channel_id_service;
-  int connection_status;
-  // Indicates that the socket should pause in the Connect method.
-  bool should_pause_on_connect;
-  // Whether or not the Socket should behave like there is a pre-existing
-  // session to resume. Whether or not such a session is reported as
-  // resumed is controlled by |connection_status|.
-  bool is_in_session_cache;
-};
-
-// A DataProvider where the client must write a request before the reads (e.g.
-// the response) will complete.
-class DelayedSocketData : public StaticSocketDataProvider {
- public:
-  // |write_delay| the number of MockWrites to complete before allowing
-  //               a MockRead to complete.
-  // |reads| the list of MockRead completions.
-  // |writes| the list of MockWrite completions.
-  // Note: For stream sockets, the MockRead list must end with a EOF, e.g., a
-  //       MockRead(true, 0, 0);
-  DelayedSocketData(int write_delay,
-                    MockRead* reads,
-                    size_t reads_count,
-                    MockWrite* writes,
-                    size_t writes_count);
-
-  // |connect| the result for the connect phase.
-  // |reads| the list of MockRead completions.
-  // |write_delay| the number of MockWrites to complete before allowing
-  //               a MockRead to complete.
-  // |writes| the list of MockWrite completions.
-  // Note: For stream sockets, the MockRead list must end with a EOF, e.g., a
-  //       MockRead(true, 0, 0);
-  DelayedSocketData(const MockConnect& connect,
-                    int write_delay,
-                    MockRead* reads,
-                    size_t reads_count,
-                    MockWrite* writes,
-                    size_t writes_count);
-  ~DelayedSocketData() override;
-
-  void ForceNextRead();
-
-  // StaticSocketDataProvider:
-  MockRead GetNextRead() override;
-  MockWriteResult OnWrite(const std::string& data) override;
-  void Reset() override;
-  void CompleteRead() override;
-
- private:
-  int write_delay_;
-  bool read_in_progress_;
-
-  base::WeakPtrFactory<DelayedSocketData> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(DelayedSocketData);
-};
-
-// A DataProvider where the reads are ordered.
-// If a read is requested before its sequence number is reached, we return an
-// ERR_IO_PENDING (that way we don't have to explicitly add a MockRead just to
-// wait).
-// The sequence number is incremented on every read and write operation.
-// The message loop may be interrupted by setting the high bit of the sequence
-// number in the MockRead's sequence number.  When that MockRead is reached,
-// we post a Quit message to the loop.  This allows us to interrupt the reading
-// of data before a complete message has arrived, and provides support for
-// testing server push when the request is issued while the response is in the
-// middle of being received.
-class OrderedSocketData : public StaticSocketDataProvider {
- public:
-  // |reads| the list of MockRead completions.
-  // |writes| the list of MockWrite completions.
-  // Note: All MockReads and MockWrites must be async.
-  // Note: For stream sockets, the MockRead list must end with a EOF, e.g., a
-  //       MockRead(true, 0, 0);
-  OrderedSocketData(MockRead* reads,
-                    size_t reads_count,
-                    MockWrite* writes,
-                    size_t writes_count);
-  ~OrderedSocketData() override;
-
-  // |connect| the result for the connect phase.
-  // |reads| the list of MockRead completions.
-  // |writes| the list of MockWrite completions.
-  // Note: All MockReads and MockWrites must be async.
-  // Note: For stream sockets, the MockRead list must end with a EOF, e.g., a
-  //       MockRead(true, 0, 0);
-  OrderedSocketData(const MockConnect& connect,
-                    MockRead* reads,
-                    size_t reads_count,
-                    MockWrite* writes,
-                    size_t writes_count);
-
-  // Posts a quit message to the current message loop, if one is running.
-  void EndLoop();
-
-  // StaticSocketDataProvider:
-  MockRead GetNextRead() override;
-  MockWriteResult OnWrite(const std::string& data) override;
-  void Reset() override;
-  void CompleteRead() override;
-
- private:
-  int sequence_number_;
-  int loop_stop_stage_;
-  bool blocked_;
-
-  base::WeakPtrFactory<OrderedSocketData> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(OrderedSocketData);
-};
-
-class DeterministicMockTCPClientSocket;
-
-// This class gives the user full control over the network activity,
-// specifically the timing of the COMPLETION of I/O operations.  Regardless of
-// the order in which I/O operations are initiated, this class ensures that they
-// complete in the correct order.
-//
-// Network activity is modeled as a sequence of numbered steps which is
-// incremented whenever an I/O operation completes.  This can happen under two
-// different circumstances:
-//
-// 1) Performing a synchronous I/O operation.  (Invoking Read() or Write()
-//    when the corresponding MockRead or MockWrite is marked !async).
-// 2) Running the Run() method of this class.  The run method will invoke
-//    the current MessageLoop, running all pending events, and will then
-//    invoke any pending IO callbacks.
-//
-// In addition, this class allows for I/O processing to "stop" at a specified
-// step, by calling SetStop(int) or StopAfter(int).  Initiating an I/O operation
-// by calling Read() or Write() while stopped is permitted if the operation is
-// asynchronous.  It is an error to perform synchronous I/O while stopped.
-//
-// When creating the MockReads and MockWrites, note that the sequence number
-// refers to the number of the step in which the I/O will complete.  In the
-// case of synchronous I/O, this will be the same step as the I/O is initiated.
-// However, in the case of asynchronous I/O, this I/O may be initiated in
-// a much earlier step. Furthermore, when the a Read() or Write() is separated
-// from its completion by other Read() or Writes()'s, it can not be marked
-// synchronous.  If it is, ERR_UNUEXPECTED will be returned indicating that a
-// synchronous Read() or Write() could not be completed synchronously because of
-// the specific ordering constraints.
-//
-// Sequence numbers are preserved across both reads and writes. There should be
-// no gaps in sequence numbers, and no repeated sequence numbers. i.e.
-//  MockRead reads[] = {
-//    MockRead(false, "first read", length, 0)   // sync
-//    MockRead(true, "second read", length, 2)   // async
-//  };
-//  MockWrite writes[] = {
-//    MockWrite(true, "first write", length, 1),    // async
-//    MockWrite(false, "second write", length, 3),  // sync
-//  };
-//
-// Example control flow:
-// Read() is called.  The current step is 0.  The first available read is
-// synchronous, so the call to Read() returns length.  The current step is
-// now 1.  Next, Read() is called again.  The next available read can
-// not be completed until step 2, so Read() returns ERR_IO_PENDING.  The current
-// step is still 1.  Write is called().  The first available write is able to
-// complete in this step, but is marked asynchronous.  Write() returns
-// ERR_IO_PENDING.  The current step is still 1.  At this point RunFor(1) is
-// called which will cause the write callback to be invoked, and will then
-// stop.  The current state is now 2.  RunFor(1) is called again, which
-// causes the read callback to be invoked, and will then stop.  Then current
-// step is 2.  Write() is called again.  Then next available write is
-// synchronous so the call to Write() returns length.
-//
-// For examples of how to use this class, see:
-//   deterministic_socket_data_unittests.cc
-class DeterministicSocketData : public StaticSocketDataProvider {
- public:
-  // The Delegate is an abstract interface which handles the communication from
-  // the DeterministicSocketData to the Deterministic MockSocket.  The
-  // MockSockets directly store a pointer to the DeterministicSocketData,
-  // whereas the DeterministicSocketData only stores a pointer to the
-  // abstract Delegate interface.
-  class Delegate {
-   public:
-    // Returns true if there is currently a write pending. That is to say, if
-    // an asynchronous write has been started but the callback has not been
-    // invoked.
-    virtual bool WritePending() const = 0;
-    // Returns true if there is currently a read pending. That is to say, if
-    // an asynchronous read has been started but the callback has not been
-    // invoked.
-    virtual bool ReadPending() const = 0;
-    // Called to complete an asynchronous write to execute the write callback.
-    virtual void CompleteWrite() = 0;
-    // Called to complete an asynchronous read to execute the read callback.
-    virtual int CompleteRead() = 0;
-
-   protected:
-    virtual ~Delegate() {}
-  };
-
-  // |reads| the list of MockRead completions.
-  // |writes| the list of MockWrite completions.
-  DeterministicSocketData(MockRead* reads,
-                          size_t reads_count,
-                          MockWrite* writes,
-                          size_t writes_count);
-  ~DeterministicSocketData() override;
-
-  // Consume all the data up to the give stop point (via SetStop()).
-  void Run();
-
-  // Set the stop point to be |steps| from now, and then invoke Run().
-  void RunFor(int steps);
-
-  // Stop at step |seq|, which must be in the future.
-  virtual void SetStop(int seq);
-
-  // Stop |seq| steps after the current step.
-  virtual void StopAfter(int seq);
-  bool stopped() const { return stopped_; }
-  void SetStopped(bool val) { stopped_ = val; }
-  MockRead& current_read() { return current_read_; }
-  MockWrite& current_write() { return current_write_; }
-  int sequence_number() const { return sequence_number_; }
-  void set_delegate(base::WeakPtr<Delegate> delegate) { delegate_ = delegate; }
-
-  // StaticSocketDataProvider:
-
-  // When the socket calls Read(), that calls GetNextRead(), and expects either
-  // ERR_IO_PENDING or data.
-  MockRead GetNextRead() override;
-
-  // When the socket calls Write(), it always completes synchronously. OnWrite()
-  // checks to make sure the written data matches the expected data. The
-  // callback will not be invoked until its sequence number is reached.
-  MockWriteResult OnWrite(const std::string& data) override;
-  void Reset() override;
-  void CompleteRead() override {}
-
- private:
-  // Invoke the read and write callbacks, if the timing is appropriate.
-  void InvokeCallbacks();
-
-  void NextStep();
-
-  void VerifyCorrectSequenceNumbers(MockRead* reads,
-                                    size_t reads_count,
-                                    MockWrite* writes,
-                                    size_t writes_count);
-
-  int sequence_number_;
-  MockRead current_read_;
-  MockWrite current_write_;
-  int stopping_sequence_number_;
-  bool stopped_;
-  base::WeakPtr<Delegate> delegate_;
-  bool print_debug_;
-  bool is_running_;
-};
-
-// Holds an array of SocketDataProvider elements.  As Mock{TCP,SSL}StreamSocket
-// objects get instantiated, they take their data from the i'th element of this
-// array.
-template <typename T>
-class SocketDataProviderArray {
- public:
-  SocketDataProviderArray() : next_index_(0) {}
-
-  T* GetNext() {
-    DCHECK_LT(next_index_, data_providers_.size());
-    return data_providers_[next_index_++];
-  }
-
-  void Add(T* data_provider) {
-    DCHECK(data_provider);
-    data_providers_.push_back(data_provider);
-  }
-
-  size_t next_index() { return next_index_; }
-
-  void ResetNextIndex() { next_index_ = 0; }
-
- private:
-  // Index of the next |data_providers_| element to use. Not an iterator
-  // because those are invalidated on vector reallocation.
-  size_t next_index_;
-
-  // SocketDataProviders to be returned.
-  std::vector<T*> data_providers_;
-};
-
-class MockUDPClientSocket;
-class MockTCPClientSocket;
-class MockSSLClientSocket;
-
-// ClientSocketFactory which contains arrays of sockets of each type.
-// You should first fill the arrays using AddMock{SSL,}Socket. When the factory
-// is asked to create a socket, it takes next entry from appropriate array.
-// You can use ResetNextMockIndexes to reset that next entry index for all mock
-// socket types.
-class MockClientSocketFactory : public ClientSocketFactory {
- public:
-  MockClientSocketFactory();
-  ~MockClientSocketFactory() override;
-
-  void AddSocketDataProvider(SocketDataProvider* socket);
-  void AddSSLSocketDataProvider(SSLSocketDataProvider* socket);
-  void ResetNextMockIndexes();
-
-  SocketDataProviderArray<SocketDataProvider>& mock_data() {
-    return mock_data_;
-  }
-
-  // Note: this method is unsafe; the elements of the returned vector
-  // are not necessarily valid.
-  const std::vector<MockSSLClientSocket*>& ssl_client_sockets() const {
-    return ssl_client_sockets_;
-  }
-
-  // ClientSocketFactory
-  scoped_ptr<DatagramClientSocket> CreateDatagramClientSocket(
-      DatagramSocket::BindType bind_type,
-      const RandIntCallback& rand_int_cb,
-      NetLog* net_log,
-      const NetLog::Source& source) override;
-  scoped_ptr<StreamSocket> CreateTransportClientSocket(
-      const AddressList& addresses,
-      NetLog* net_log,
-      const NetLog::Source& source) override;
-  scoped_ptr<SSLClientSocket> CreateSSLClientSocket(
-      scoped_ptr<ClientSocketHandle> transport_socket,
-      const HostPortPair& host_and_port,
-      const SSLConfig& ssl_config,
-      const SSLClientSocketContext& context) override;
-  void ClearSSLSessionCache() override;
-
- private:
-  SocketDataProviderArray<SocketDataProvider> mock_data_;
-  SocketDataProviderArray<SSLSocketDataProvider> mock_ssl_data_;
-  std::vector<MockSSLClientSocket*> ssl_client_sockets_;
-};
-
-class MockClientSocket : public SSLClientSocket {
- public:
-  // Value returned by GetTLSUniqueChannelBinding().
-  static const char kTlsUnique[];
-
-  // The BoundNetLog is needed to test LoadTimingInfo, which uses NetLog IDs as
-  // unique socket IDs.
-  explicit MockClientSocket(const BoundNetLog& net_log);
-
-  // Socket implementation.
-  int Read(IOBuffer* buf,
-           int buf_len,
-           const CompletionCallback& callback) override = 0;
-  int Write(IOBuffer* buf,
-            int buf_len,
-            const CompletionCallback& callback) override = 0;
-  int SetReceiveBufferSize(int32 size) override;
-  int SetSendBufferSize(int32 size) override;
-
-  // StreamSocket implementation.
-  int Connect(const CompletionCallback& callback) override = 0;
-  void Disconnect() override;
-  bool IsConnected() const override;
-  bool IsConnectedAndIdle() const override;
-  int GetPeerAddress(IPEndPoint* address) const override;
-  int GetLocalAddress(IPEndPoint* address) const override;
-  const BoundNetLog& NetLog() const override;
-  void SetSubresourceSpeculation() override {}
-  void SetOmniboxSpeculation() override {}
-
-  // SSLClientSocket implementation.
-  std::string GetSessionCacheKey() const override;
-  bool InSessionCache() const override;
-  void SetHandshakeCompletionCallback(const base::Closure& cb) override;
-  void GetSSLCertRequestInfo(SSLCertRequestInfo* cert_request_info) override;
-  int ExportKeyingMaterial(const base::StringPiece& label,
-                           bool has_context,
-                           const base::StringPiece& context,
-                           unsigned char* out,
-                           unsigned int outlen) override;
-  int GetTLSUniqueChannelBinding(std::string* out) override;
-  NextProtoStatus GetNextProto(std::string* proto) override;
-  ChannelIDService* GetChannelIDService() const override;
-
- protected:
-  ~MockClientSocket() override;
-  void RunCallbackAsync(const CompletionCallback& callback, int result);
-  void RunCallback(const CompletionCallback& callback, int result);
-
-  // SSLClientSocket implementation.
-  scoped_refptr<X509Certificate> GetUnverifiedServerCertificateChain()
-      const override;
-
-  // True if Connect completed successfully and Disconnect hasn't been called.
-  bool connected_;
-
-  // Address of the "remote" peer we're connected to.
-  IPEndPoint peer_addr_;
-
-  BoundNetLog net_log_;
-
- private:
-  base::WeakPtrFactory<MockClientSocket> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(MockClientSocket);
-};
-
-class MockTCPClientSocket : public MockClientSocket, public AsyncSocket {
- public:
-  MockTCPClientSocket(const AddressList& addresses,
-                      net::NetLog* net_log,
-                      SocketDataProvider* socket);
-  ~MockTCPClientSocket() override;
-
-  const AddressList& addresses() const { return addresses_; }
-
-  // Socket implementation.
-  int Read(IOBuffer* buf,
-           int buf_len,
-           const CompletionCallback& callback) override;
-  int Write(IOBuffer* buf,
-            int buf_len,
-            const CompletionCallback& callback) override;
-
-  // StreamSocket implementation.
-  int Connect(const CompletionCallback& callback) override;
-  void Disconnect() override;
-  bool IsConnected() const override;
-  bool IsConnectedAndIdle() const override;
-  int GetPeerAddress(IPEndPoint* address) const override;
-  bool WasEverUsed() const override;
-  bool UsingTCPFastOpen() const override;
-  bool WasNpnNegotiated() const override;
-  bool GetSSLInfo(SSLInfo* ssl_info) override;
-
-  // AsyncSocket:
-  void OnReadComplete(const MockRead& data) override;
-  void OnConnectComplete(const MockConnect& data) override;
-
- private:
-  int CompleteRead();
-
-  AddressList addresses_;
-
-  SocketDataProvider* data_;
-  int read_offset_;
-  MockRead read_data_;
-  bool need_read_data_;
-
-  // True if the peer has closed the connection.  This allows us to simulate
-  // the recv(..., MSG_PEEK) call in the IsConnectedAndIdle method of the real
-  // TCPClientSocket.
-  bool peer_closed_connection_;
-
-  // While an asynchronous IO is pending, we save our user-buffer state.
-  scoped_refptr<IOBuffer> pending_buf_;
-  int pending_buf_len_;
-  CompletionCallback pending_callback_;
-  bool was_used_to_convey_data_;
-
-  DISALLOW_COPY_AND_ASSIGN(MockTCPClientSocket);
-};
-
-// DeterministicSocketHelper is a helper class that can be used
-// to simulate net::Socket::Read() and net::Socket::Write()
-// using deterministic |data|.
-// Note: This is provided as a common helper class because
-// of the inheritance hierarchy of DeterministicMock[UDP,TCP]ClientSocket and a
-// desire not to introduce an additional common base class.
-class DeterministicSocketHelper {
- public:
-  DeterministicSocketHelper(net::NetLog* net_log,
-                            DeterministicSocketData* data);
-  virtual ~DeterministicSocketHelper();
-
-  bool write_pending() const { return write_pending_; }
-  bool read_pending() const { return read_pending_; }
-
-  void CompleteWrite();
-  int CompleteRead();
-
-  int Write(IOBuffer* buf, int buf_len, const CompletionCallback& callback);
-  int Read(IOBuffer* buf, int buf_len, const CompletionCallback& callback);
-
-  const BoundNetLog& net_log() const { return net_log_; }
-
-  bool was_used_to_convey_data() const { return was_used_to_convey_data_; }
-
-  bool peer_closed_connection() const { return peer_closed_connection_; }
-
-  DeterministicSocketData* data() const { return data_; }
-
- private:
-  bool write_pending_;
-  CompletionCallback write_callback_;
-  int write_result_;
-
-  MockRead read_data_;
-
-  IOBuffer* read_buf_;
-  int read_buf_len_;
-  bool read_pending_;
-  CompletionCallback read_callback_;
-  DeterministicSocketData* data_;
-  bool was_used_to_convey_data_;
-  bool peer_closed_connection_;
-  BoundNetLog net_log_;
-};
-
-// Mock UDP socket to be used in conjunction with DeterministicSocketData.
-class DeterministicMockUDPClientSocket
-    : public DatagramClientSocket,
-      public AsyncSocket,
-      public DeterministicSocketData::Delegate,
-      public base::SupportsWeakPtr<DeterministicMockUDPClientSocket> {
- public:
-  DeterministicMockUDPClientSocket(net::NetLog* net_log,
-                                   DeterministicSocketData* data);
-  ~DeterministicMockUDPClientSocket() override;
-
-  // DeterministicSocketData::Delegate:
-  bool WritePending() const override;
-  bool ReadPending() const override;
-  void CompleteWrite() override;
-  int CompleteRead() override;
-
-  // Socket implementation.
-  int Read(IOBuffer* buf,
-           int buf_len,
-           const CompletionCallback& callback) override;
-  int Write(IOBuffer* buf,
-            int buf_len,
-            const CompletionCallback& callback) override;
-  int SetReceiveBufferSize(int32 size) override;
-  int SetSendBufferSize(int32 size) override;
-
-  // DatagramSocket implementation.
-  void Close() override;
-  int GetPeerAddress(IPEndPoint* address) const override;
-  int GetLocalAddress(IPEndPoint* address) const override;
-  const BoundNetLog& NetLog() const override;
-
-  // DatagramClientSocket implementation.
-  int Connect(const IPEndPoint& address) override;
-
-  // AsyncSocket implementation.
-  void OnReadComplete(const MockRead& data) override;
-  void OnConnectComplete(const MockConnect& data) override;
-
-  void set_source_port(uint16 port) { source_port_ = port; }
-
- private:
-  bool connected_;
-  IPEndPoint peer_address_;
-  DeterministicSocketHelper helper_;
-  uint16 source_port_;  // Ephemeral source port.
-
-  DISALLOW_COPY_AND_ASSIGN(DeterministicMockUDPClientSocket);
-};
-
-// Mock TCP socket to be used in conjunction with DeterministicSocketData.
-class DeterministicMockTCPClientSocket
-    : public MockClientSocket,
-      public AsyncSocket,
-      public DeterministicSocketData::Delegate,
-      public base::SupportsWeakPtr<DeterministicMockTCPClientSocket> {
- public:
-  DeterministicMockTCPClientSocket(net::NetLog* net_log,
-                                   DeterministicSocketData* data);
-  ~DeterministicMockTCPClientSocket() override;
-
-  // DeterministicSocketData::Delegate:
-  bool WritePending() const override;
-  bool ReadPending() const override;
-  void CompleteWrite() override;
-  int CompleteRead() override;
-
-  // Socket:
-  int Write(IOBuffer* buf,
-            int buf_len,
-            const CompletionCallback& callback) override;
-  int Read(IOBuffer* buf,
-           int buf_len,
-           const CompletionCallback& callback) override;
-
-  // StreamSocket:
-  int Connect(const CompletionCallback& callback) override;
-  void Disconnect() override;
-  bool IsConnected() const override;
-  bool IsConnectedAndIdle() const override;
-  bool WasEverUsed() const override;
-  bool UsingTCPFastOpen() const override;
-  bool WasNpnNegotiated() const override;
-  bool GetSSLInfo(SSLInfo* ssl_info) override;
-
-  // AsyncSocket:
-  void OnReadComplete(const MockRead& data) override;
-  void OnConnectComplete(const MockConnect& data) override;
-
- private:
-  DeterministicSocketHelper helper_;
-
-  DISALLOW_COPY_AND_ASSIGN(DeterministicMockTCPClientSocket);
-};
-
-class MockSSLClientSocket : public MockClientSocket, public AsyncSocket {
- public:
-  MockSSLClientSocket(scoped_ptr<ClientSocketHandle> transport_socket,
-                      const HostPortPair& host_and_port,
-                      const SSLConfig& ssl_config,
-                      SSLSocketDataProvider* socket);
-  ~MockSSLClientSocket() override;
-
-  // Socket implementation.
-  int Read(IOBuffer* buf,
-           int buf_len,
-           const CompletionCallback& callback) override;
-  int Write(IOBuffer* buf,
-            int buf_len,
-            const CompletionCallback& callback) override;
-
-  // StreamSocket implementation.
-  int Connect(const CompletionCallback& callback) override;
-  void Disconnect() override;
-  bool IsConnected() const override;
-  bool WasEverUsed() const override;
-  bool UsingTCPFastOpen() const override;
-  int GetPeerAddress(IPEndPoint* address) const override;
-  bool WasNpnNegotiated() const override;
-  bool GetSSLInfo(SSLInfo* ssl_info) override;
-
-  // SSLClientSocket implementation.
-  std::string GetSessionCacheKey() const override;
-  bool InSessionCache() const override;
-  void SetHandshakeCompletionCallback(const base::Closure& cb) override;
-  void GetSSLCertRequestInfo(SSLCertRequestInfo* cert_request_info) override;
-  NextProtoStatus GetNextProto(std::string* proto) override;
-  bool set_was_npn_negotiated(bool negotiated) override;
-  void set_protocol_negotiated(NextProto protocol_negotiated) override;
-  NextProto GetNegotiatedProtocol() const override;
-
-  // This MockSocket does not implement the manual async IO feature.
-  void OnReadComplete(const MockRead& data) override;
-  void OnConnectComplete(const MockConnect& data) override;
-
-  bool WasChannelIDSent() const override;
-  void set_channel_id_sent(bool channel_id_sent) override;
-  ChannelIDService* GetChannelIDService() const override;
-
-  bool reached_connect() const { return reached_connect_; }
-
-  // Resumes the connection of a socket that was paused for testing.
-  // |connect_callback_| should be set before invoking this method.
-  void RestartPausedConnect();
-
- private:
-  enum ConnectState {
-    STATE_NONE,
-    STATE_SSL_CONNECT,
-    STATE_SSL_CONNECT_COMPLETE,
-  };
-
-  void OnIOComplete(int result);
-
-  // Runs the state transistion loop.
-  int DoConnectLoop(int result);
-
-  int DoSSLConnect();
-  int DoSSLConnectComplete(int result);
-
-  scoped_ptr<ClientSocketHandle> transport_;
-  HostPortPair host_port_pair_;
-  SSLSocketDataProvider* data_;
-  bool is_npn_state_set_;
-  bool new_npn_value_;
-  bool is_protocol_negotiated_set_;
-  NextProto protocol_negotiated_;
-
-  CompletionCallback connect_callback_;
-  // Indicates what state of Connect the socket should enter.
-  ConnectState next_connect_state_;
-  // True if the Connect method has been called on the socket.
-  bool reached_connect_;
-
-  base::Closure handshake_completion_callback_;
-
-  base::WeakPtrFactory<MockSSLClientSocket> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(MockSSLClientSocket);
-};
-
-class MockUDPClientSocket : public DatagramClientSocket, public AsyncSocket {
- public:
-  MockUDPClientSocket(SocketDataProvider* data, net::NetLog* net_log);
-  ~MockUDPClientSocket() override;
-
-  // Socket implementation.
-  int Read(IOBuffer* buf,
-           int buf_len,
-           const CompletionCallback& callback) override;
-  int Write(IOBuffer* buf,
-            int buf_len,
-            const CompletionCallback& callback) override;
-  int SetReceiveBufferSize(int32 size) override;
-  int SetSendBufferSize(int32 size) override;
-
-  // DatagramSocket implementation.
-  void Close() override;
-  int GetPeerAddress(IPEndPoint* address) const override;
-  int GetLocalAddress(IPEndPoint* address) const override;
-  const BoundNetLog& NetLog() const override;
-
-  // DatagramClientSocket implementation.
-  int Connect(const IPEndPoint& address) override;
-
-  // AsyncSocket implementation.
-  void OnReadComplete(const MockRead& data) override;
-  void OnConnectComplete(const MockConnect& data) override;
-
-  void set_source_port(uint16 port) { source_port_ = port;}
-
- private:
-  int CompleteRead();
-
-  void RunCallbackAsync(const CompletionCallback& callback, int result);
-  void RunCallback(const CompletionCallback& callback, int result);
-
-  bool connected_;
-  SocketDataProvider* data_;
-  int read_offset_;
-  MockRead read_data_;
-  bool need_read_data_;
-  uint16 source_port_;  // Ephemeral source port.
-
-  // Address of the "remote" peer we're connected to.
-  IPEndPoint peer_addr_;
-
-  // While an asynchronous IO is pending, we save our user-buffer state.
-  scoped_refptr<IOBuffer> pending_buf_;
-  int pending_buf_len_;
-  CompletionCallback pending_callback_;
-
-  BoundNetLog net_log_;
-
-  base::WeakPtrFactory<MockUDPClientSocket> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(MockUDPClientSocket);
-};
-
-class TestSocketRequest : public TestCompletionCallbackBase {
- public:
-  TestSocketRequest(std::vector<TestSocketRequest*>* request_order,
-                    size_t* completion_count);
-  ~TestSocketRequest() override;
-
-  ClientSocketHandle* handle() { return &handle_; }
-
-  const net::CompletionCallback& callback() const { return callback_; }
-
- private:
-  void OnComplete(int result);
-
-  ClientSocketHandle handle_;
-  std::vector<TestSocketRequest*>* request_order_;
-  size_t* completion_count_;
-  CompletionCallback callback_;
-
-  DISALLOW_COPY_AND_ASSIGN(TestSocketRequest);
-};
-
-class ClientSocketPoolTest {
- public:
-  enum KeepAlive {
-    KEEP_ALIVE,
-
-    // A socket will be disconnected in addition to handle being reset.
-    NO_KEEP_ALIVE,
-  };
-
-  static const int kIndexOutOfBounds;
-  static const int kRequestNotFound;
-
-  ClientSocketPoolTest();
-  ~ClientSocketPoolTest();
-
-  template <typename PoolType>
-  int StartRequestUsingPool(
-      PoolType* socket_pool,
-      const std::string& group_name,
-      RequestPriority priority,
-      const scoped_refptr<typename PoolType::SocketParams>& socket_params) {
-    DCHECK(socket_pool);
-    TestSocketRequest* request =
-        new TestSocketRequest(&request_order_, &completion_count_);
-    requests_.push_back(request);
-    int rv = request->handle()->Init(group_name,
-                                     socket_params,
-                                     priority,
-                                     request->callback(),
-                                     socket_pool,
-                                     BoundNetLog());
-    if (rv != ERR_IO_PENDING)
-      request_order_.push_back(request);
-    return rv;
-  }
-
-  // Provided there were n requests started, takes |index| in range 1..n
-  // and returns order in which that request completed, in range 1..n,
-  // or kIndexOutOfBounds if |index| is out of bounds, or kRequestNotFound
-  // if that request did not complete (for example was canceled).
-  int GetOrderOfRequest(size_t index) const;
-
-  // Resets first initialized socket handle from |requests_|. If found such
-  // a handle, returns true.
-  bool ReleaseOneConnection(KeepAlive keep_alive);
-
-  // Releases connections until there is nothing to release.
-  void ReleaseAllConnections(KeepAlive keep_alive);
-
-  // Note that this uses 0-based indices, while GetOrderOfRequest takes and
-  // returns 0-based indices.
-  TestSocketRequest* request(int i) { return requests_[i]; }
-
-  size_t requests_size() const { return requests_.size(); }
-  ScopedVector<TestSocketRequest>* requests() { return &requests_; }
-  size_t completion_count() const { return completion_count_; }
-
- private:
-  ScopedVector<TestSocketRequest> requests_;
-  std::vector<TestSocketRequest*> request_order_;
-  size_t completion_count_;
-
-  DISALLOW_COPY_AND_ASSIGN(ClientSocketPoolTest);
-};
-
-class MockTransportSocketParams
-    : public base::RefCounted<MockTransportSocketParams> {
- private:
-  friend class base::RefCounted<MockTransportSocketParams>;
-  ~MockTransportSocketParams() {}
-
-  DISALLOW_COPY_AND_ASSIGN(MockTransportSocketParams);
-};
-
-class MockTransportClientSocketPool : public TransportClientSocketPool {
- public:
-  typedef MockTransportSocketParams SocketParams;
-
-  class MockConnectJob {
-   public:
-    MockConnectJob(scoped_ptr<StreamSocket> socket,
-                   ClientSocketHandle* handle,
-                   const CompletionCallback& callback);
-    ~MockConnectJob();
-
-    int Connect();
-    bool CancelHandle(const ClientSocketHandle* handle);
-
-   private:
-    void OnConnect(int rv);
-
-    scoped_ptr<StreamSocket> socket_;
-    ClientSocketHandle* handle_;
-    CompletionCallback user_callback_;
-
-    DISALLOW_COPY_AND_ASSIGN(MockConnectJob);
-  };
-
-  MockTransportClientSocketPool(int max_sockets,
-                                int max_sockets_per_group,
-                                ClientSocketPoolHistograms* histograms,
-                                ClientSocketFactory* socket_factory);
-
-  ~MockTransportClientSocketPool() override;
-
-  RequestPriority last_request_priority() const {
-    return last_request_priority_;
-  }
-  int release_count() const { return release_count_; }
-  int cancel_count() const { return cancel_count_; }
-
-  // TransportClientSocketPool implementation.
-  int RequestSocket(const std::string& group_name,
-                    const void* socket_params,
-                    RequestPriority priority,
-                    ClientSocketHandle* handle,
-                    const CompletionCallback& callback,
-                    const BoundNetLog& net_log) override;
-
-  void CancelRequest(const std::string& group_name,
-                     ClientSocketHandle* handle) override;
-  void ReleaseSocket(const std::string& group_name,
-                     scoped_ptr<StreamSocket> socket,
-                     int id) override;
-
- private:
-  ClientSocketFactory* client_socket_factory_;
-  ScopedVector<MockConnectJob> job_list_;
-  RequestPriority last_request_priority_;
-  int release_count_;
-  int cancel_count_;
-
-  DISALLOW_COPY_AND_ASSIGN(MockTransportClientSocketPool);
-};
-
-class DeterministicMockClientSocketFactory : public ClientSocketFactory {
- public:
-  DeterministicMockClientSocketFactory();
-  ~DeterministicMockClientSocketFactory() override;
-
-  void AddSocketDataProvider(DeterministicSocketData* socket);
-  void AddSSLSocketDataProvider(SSLSocketDataProvider* socket);
-  void ResetNextMockIndexes();
-
-  // Return |index|-th MockSSLClientSocket (starting from 0) that the factory
-  // created.
-  MockSSLClientSocket* GetMockSSLClientSocket(size_t index) const;
-
-  SocketDataProviderArray<DeterministicSocketData>& mock_data() {
-    return mock_data_;
-  }
-  std::vector<DeterministicMockTCPClientSocket*>& tcp_client_sockets() {
-    return tcp_client_sockets_;
-  }
-  std::vector<DeterministicMockUDPClientSocket*>& udp_client_sockets() {
-    return udp_client_sockets_;
-  }
-
-  // ClientSocketFactory
-  scoped_ptr<DatagramClientSocket> CreateDatagramClientSocket(
-      DatagramSocket::BindType bind_type,
-      const RandIntCallback& rand_int_cb,
-      NetLog* net_log,
-      const NetLog::Source& source) override;
-  scoped_ptr<StreamSocket> CreateTransportClientSocket(
-      const AddressList& addresses,
-      NetLog* net_log,
-      const NetLog::Source& source) override;
-  scoped_ptr<SSLClientSocket> CreateSSLClientSocket(
-      scoped_ptr<ClientSocketHandle> transport_socket,
-      const HostPortPair& host_and_port,
-      const SSLConfig& ssl_config,
-      const SSLClientSocketContext& context) override;
-  void ClearSSLSessionCache() override;
-
- private:
-  SocketDataProviderArray<DeterministicSocketData> mock_data_;
-  SocketDataProviderArray<SSLSocketDataProvider> mock_ssl_data_;
-
-  // Store pointers to handed out sockets in case the test wants to get them.
-  std::vector<DeterministicMockTCPClientSocket*> tcp_client_sockets_;
-  std::vector<DeterministicMockUDPClientSocket*> udp_client_sockets_;
-  std::vector<MockSSLClientSocket*> ssl_client_sockets_;
-
-  DISALLOW_COPY_AND_ASSIGN(DeterministicMockClientSocketFactory);
-};
-
-class MockSOCKSClientSocketPool : public SOCKSClientSocketPool {
- public:
-  MockSOCKSClientSocketPool(int max_sockets,
-                            int max_sockets_per_group,
-                            ClientSocketPoolHistograms* histograms,
-                            TransportClientSocketPool* transport_pool);
-
-  ~MockSOCKSClientSocketPool() override;
-
-  // SOCKSClientSocketPool implementation.
-  int RequestSocket(const std::string& group_name,
-                    const void* socket_params,
-                    RequestPriority priority,
-                    ClientSocketHandle* handle,
-                    const CompletionCallback& callback,
-                    const BoundNetLog& net_log) override;
-
-  void CancelRequest(const std::string& group_name,
-                     ClientSocketHandle* handle) override;
-  void ReleaseSocket(const std::string& group_name,
-                     scoped_ptr<StreamSocket> socket,
-                     int id) override;
-
- private:
-  TransportClientSocketPool* const transport_pool_;
-
-  DISALLOW_COPY_AND_ASSIGN(MockSOCKSClientSocketPool);
-};
-
-// Convenience class to temporarily set the WebSocketEndpointLockManager unlock
-// delay to zero for testing purposes. Automatically restores the original value
-// when destroyed.
-class ScopedWebSocketEndpointZeroUnlockDelay {
- public:
-  ScopedWebSocketEndpointZeroUnlockDelay();
-  ~ScopedWebSocketEndpointZeroUnlockDelay();
-
- private:
-  base::TimeDelta old_delay_;
-};
-
-// Constants for a successful SOCKS v5 handshake.
-extern const char kSOCKS5GreetRequest[];
-extern const int kSOCKS5GreetRequestLength;
-
-extern const char kSOCKS5GreetResponse[];
-extern const int kSOCKS5GreetResponseLength;
-
-extern const char kSOCKS5OkRequest[];
-extern const int kSOCKS5OkRequestLength;
-
-extern const char kSOCKS5OkResponse[];
-extern const int kSOCKS5OkResponseLength;
-
-}  // namespace net
-
-#endif  // NET_SOCKET_SOCKET_TEST_UTIL_H_