Key.h

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/* -*- c++ -*-
 * Copyright (C) 2007-2015 Hypertable, Inc.
 *
 * This file is part of Hypertable.
 *
 * Hypertable 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; version 3 of the
 * License, or any later version.
 *
 * Hypertable 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.
 */

#ifndef HYPERTABLE_KEY_H
#define HYPERTABLE_KEY_H

#include <iostream>

#include <boost/shared_array.hpp>
#include <boost/detail/endian.hpp>

#include "Common/ByteString.h"
#include "Common/DynamicBuffer.h"

#include "KeySpec.h"
#include "SerializedKey.h"


namespace Hypertable {
  class Key {
  public:

    static const uint8_t HAVE_REVISION      =  0x80;
    static const uint8_t HAVE_TIMESTAMP     =  0x40;
    static const uint8_t AUTO_TIMESTAMP     =  0x20;
    static const uint8_t REV_IS_TS          =  0x10;
    static const uint8_t TS_CHRONOLOGICAL   =   0x1;

    static const char *END_ROW_MARKER;
    static const char *END_ROOT_ROW;

    static inline void encode_ts64(uint8_t **bufp, int64_t val,
            bool ascending=true) {
      if (ascending)
        val = ~val;
#ifdef HT_LITTLE_ENDIAN
      *(*bufp)++ = (uint8_t)(val >> 56);
      *(*bufp)++ = (uint8_t)(val >> 48);
      *(*bufp)++ = (uint8_t)(val >> 40);
      *(*bufp)++ = (uint8_t)(val >> 32);
      *(*bufp)++ = (uint8_t)(val >> 24);
      *(*bufp)++ = (uint8_t)(val >> 16);
      *(*bufp)++ = (uint8_t)(val >> 8);
      *(*bufp)++ = (uint8_t)val;
#else
      memcpy(*bufp, &val, 8);
      *bufp += 8;
#endif
    }

    static inline int64_t decode_ts64(const uint8_t **bufp, 
            bool ascending=true) {
      int64_t val;
#ifdef HT_LITTLE_ENDIAN
      val = ((int64_t)*(*bufp)++ << 56);
      val |= ((int64_t)(*(*bufp)++) << 48);
      val |= ((int64_t)(*(*bufp)++) << 40);
      val |= ((int64_t)(*(*bufp)++) << 32);
      val |= ((int64_t)(*(*bufp)++) << 24);
      val |= (*(*bufp)++ << 16);
      val |= (*(*bufp)++ << 8);
      val |= *(*bufp)++;
#else
      memcpy(&val, *bufp, 8);
      *bufp += 8;
#endif
      return (ascending ? ~val : val);
    }

    Key() : flag(FLAG_INSERT), column_family_code(0), row_key_set(false),
            row(0), column_qualifier(0), row_len(0), column_qualifier_len(0),
            timestamp(0), revision(AUTO_ASSIGN){ }

    Key(const SerializedKey& key);

    bool load(const SerializedKey& key);

    size_t len_row() const { return row_len; }

    size_t len_column_family() const {
      return(column_qualifier - row);
    }

    size_t len_cell() const {
      return (column_qualifier - row) + column_qualifier_len;
    }

    SerializedKey  serial;
    uint32_t       length;  // length of serialized key
    uint8_t        flag;
    uint8_t        control;
    uint8_t        column_family_code;
    bool           row_key_set;
    const char    *row;
    const char    *column_qualifier;
    uint32_t       row_len;                     // excluding null byte
    uint32_t       column_qualifier_len;        // ditto
    const uint8_t *flag_ptr;
    int64_t        timestamp;
    int64_t        revision;
  };


  std::ostream &operator<<(std::ostream &os, const Key &key);

  inline std::ostream &
  operator<<(std::ostream &os, const SerializedKey &serkey) {
    Key key(serkey);
    os << key;
    return os;
  }

  void create_key_and_append(DynamicBuffer &dst_buf, const char *row,
                             bool time_order_asc = true);

  void create_key_and_append(DynamicBuffer &dst_buf, uint8_t flag,
                             const char *row, uint8_t column_family_code,
                             const char *column_qualifier,
                             int64_t timestamp = AUTO_ASSIGN,
                             int64_t revision = AUTO_ASSIGN,
                             bool time_order_asc = true);

  void create_key_and_append(DynamicBuffer &dst_buf, const Key& key,
                             bool time_order_asc = true);

} // namespace Hypertable

#endif // HYPERTABLE_KEY_H