Class: Innodb::UndoLog

Inherits:
Object
  • Object
show all
Defined in:
lib/innodb/undo_log.rb

Defined Under Namespace

Classes: UndoRecordCursor

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(page, position) ⇒ UndoLog

Returns a new instance of UndoLog.



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# File 'lib/innodb/undo_log.rb', line 6

def initialize(page, position)
  @page = page
  @position = position
end

Instance Attribute Details

#page ⇒ Object (readonly)

Returns the value of attribute page.



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# File 'lib/innodb/undo_log.rb', line 4

def page
  @page
end

#position ⇒ Object (readonly)

Returns the value of attribute position.



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# File 'lib/innodb/undo_log.rb', line 5

def position
  @position
end

Instance Method Details

#dump ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 129

def dump
  puts "header:"
  pp header
  puts
end

#first_undo_record_cursor ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 125

def first_undo_record_cursor
  undo_record_cursor(header[:log_start_offset])
end

#header ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 19

def header
  @header ||= page.cursor(@position).name("header") do |c|
    xid_flag = nil
    {
      :trx_id => c.name("trx_id") { c.get_uint64 },
      :trx_no => c.name("trx_no") { c.get_uint64 },
      :delete_mark_flag => c.name("delete_mark_flag") { (c.get_uint16 != 0) },
      :log_start_offset => c.name("log_start_offset") { c.get_uint16 },
      :xid_flag => c.name("xid_flag") { xid_flag = (c.get_uint8 != 0) },
      :ddl_flag => c.name("ddl_flag") { (c.get_uint8 != 0) },
      :ddl_table_id => c.name("ddl_table_id") { c.get_uint64 },
      :next_log_offset => c.name("next_log_offset") { c.get_uint16 },
      :prev_log_offset => c.name("prev_log_offset") { c.get_uint16 },
      :history_list_node => c.name("history_list_node") {
        Innodb::List.get_node(c)
      },
      :xid => c.name("xid") {
        if xid_flag
          {
            :format => c.name("format") { c.get_uint32 },
            :trid_len => c.name("trid_len") { c.get_uint32 },
            :bqual_len => c.name("bqual_len") { c.get_uint32 },
            :data => c.name("data") { c.get_bytes(128) },
          }
        end
      },
    }
  end
end

#min_undo_record ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 63

def min_undo_record
  undo_record(header[:log_start_offset])
end

#next_address ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 53

def next_address
  header[:history_list_node][:next]
end

#prev_address ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 49

def prev_address
  header[:history_list_node][:prev]
end

#size_header ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 15

def size_header
  8 + 8 + 2 + 2 + 1 + 1 + 8 + 2 + 2 + Innodb::List::NODE_SIZE + size_xa_header
end

#size_xa_header ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 11

def size_xa_header
  4 + 4 + 4 + 128
end

#undo_record(offset) ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 57

def undo_record(offset)
  new_undo_record = Innodb::UndoRecord.new(page, offset)
  new_undo_record.undo_log = self
  new_undo_record
end

#undo_record_cursor(offset, direction = :forward) ⇒ Object 



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# File 'lib/innodb/undo_log.rb', line 121

def undo_record_cursor(offset, direction=:forward)
  UndoRecordCursor.new(self, offset, direction)
end