text: /* <!-- copyright */
  /*
   * aria2 - The high speed download utility
   *
   * Copyright (C) 2010 Tatsuhiro Tsujikawa
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   *
   * In addition, as a special exception, the copyright holders give
   * permission to link the code of portions of this program with the
   * OpenSSL library under certain conditions as described in each
   * individual source file, and distribute linked combinations
   * including the two.
   * You must obey the GNU General Public License in all respects
   * for all of the code used other than OpenSSL.  If you modify
   * file(s) with this exception, you may extend this exception to your
   * version of the file(s), but you are not obligated to do so.  If you
   * do not wish to do so, delete this exception statement from your
   * version.  If you delete this exception statement from all source
   * files in the program, then also delete it here.
   */
  /* copyright --> */
  #ifndef D_SOCKET_BUFFER_H
  #define D_SOCKET_BUFFER_H
  
  #include "common.h"
  
  #include <string>
  #include <deque>
  #include <memory>
  #include <vector>
  
  namespace aria2 {
  
  class SocketCore;
  
  struct ProgressUpdate {
    virtual ~ProgressUpdate() = default;
    virtual void update(size_t length, bool complete) = 0;
  };
  
  class SocketBuffer {
  private:
    class BufEntry {
    public:
      BufEntry(std::unique_ptr<ProgressUpdate> progressUpdate)
          : progressUpdate_(std::move(progressUpdate))
      {
      }
      virtual ~BufEntry() = default;
      virtual ssize_t send(const std::shared_ptr<SocketCore>& socket,
                           size_t offset) = 0;
      virtual bool final(size_t offset) const = 0;
      virtual size_t getLength() const = 0;
      virtual const unsigned char* getData() const = 0;
      void progressUpdate(size_t length, bool complete)
      {
        if (progressUpdate_) {
          progressUpdate_->update(length, complete);
        }
      }
  
    private:
      std::unique_ptr<ProgressUpdate> progressUpdate_;
    };
  
    class ByteArrayBufEntry : public BufEntry {
    public:
      ByteArrayBufEntry(std::vector<unsigned char> bytes,
                        std::unique_ptr<ProgressUpdate> progressUpdate);
      virtual ~ByteArrayBufEntry();
      virtual ssize_t send(const std::shared_ptr<SocketCore>& socket,
                           size_t offset) CXX11_OVERRIDE;
      virtual bool final(size_t offset) const CXX11_OVERRIDE;
      virtual size_t getLength() const CXX11_OVERRIDE;
      virtual const unsigned char* getData() const CXX11_OVERRIDE;
  
    private:
      std::vector<unsigned char> bytes_;
    };
  
    class StringBufEntry : public BufEntry {
    public:
      StringBufEntry(std::string s,
                     std::unique_ptr<ProgressUpdate> progressUpdate);
      virtual ssize_t send(const std::shared_ptr<SocketCore>& socket,
                           size_t offset) CXX11_OVERRIDE;
      virtual bool final(size_t offset) const CXX11_OVERRIDE;
      virtual size_t getLength() const CXX11_OVERRIDE;
      virtual const unsigned char* getData() const CXX11_OVERRIDE;
  
    private:
      std::string str_;
    };
  
    std::shared_ptr<SocketCore> socket_;
  
    std::deque<std::unique_ptr<BufEntry>> bufq_;
  
    // Offset of data in bufq_[0]. SocketBuffer tries to send bufq_[0],
    // but it cannot always send whole data. In this case, offset points
    // to the data to be sent in the next send() call.
    size_t offset_;
  
  public:
    SocketBuffer(std::shared_ptr<SocketCore> socket);
  
    ~SocketBuffer();
  
    // Don't allow copying
    SocketBuffer(const SocketBuffer&) = delete;
    SocketBuffer& operator=(const SocketBuffer&) = delete;
  
    // Feeds |bytes| into queue. This function doesn't send data.  If
    // progressUpdate is not null, its update() function will be called
    // each time the data is sent. It will be deleted by this object. It
    // can be null.
    void pushBytes(std::vector<unsigned char> bytes,
                   std::unique_ptr<ProgressUpdate> progressUpdate = nullptr);
  
    // Feeds data into queue. This function doesn't send data.  If
    // progressUpdate is not null, its update() function will be called
    // each time the data is sent. It will be deleted by this object. It
    // can be null.
    void pushStr(std::string data,
                 std::unique_ptr<ProgressUpdate> progressUpdate = nullptr);
  
    // Sends data in queue.  Returns the number of bytes sent.
    ssize_t send();
  
    // Returns true if queue is empty.
    bool sendBufferIsEmpty() const;
  
    size_t getBufferEntrySize() const { return bufq_.size(); }
  };
  
  } // namespace aria2
  
  #endif // D_SOCKET_BUFFER_H
  