qqwry

qqwry.rb

# encoding : utf-8
require 'iconv'
 
module IPSearchAsk
    class IpSearch
        def initialize(file='public/IP_database/qqwry.dat')
            filename = file
            @file = File.open(filename,"r")
            @index_first,@index_last  = @file.read(8).unpack('L2')
                @index_total = (@index_last - @index_first)/7 + 1
                @location = {}
        end
     
        #把IP转换为长整形
        def ip2long(ip)
          long = 0
          ip.split(/\./).each_with_index do |b, i|
            long += b.to_i << 8*(3-i)
          end
          long
        end
     
        #读取偏移值
        def read_offset(position)
            @file.seek position
            chars = @file.read(3).unpack('C3')
            (chars[2]<<16) + (chars[1]<<8) + chars[0]
        end
     
        #读取记录中的4字节作为一个long值
        def read_long(position)
            @file.seek position
            @file.read(4).unpack('L')[0]
        end
     
        #读取模式信息，1和2为正常，其他值异常
        #position:字符串偏移量
        def read_mode(position)
            @file.seek position #前4位为IP值
            @file.read(1).unpack('C')[0]
        end
     
        #根据IP在索引中查找具体位置
        def find_str_offset(ip_long)
            offset_min,offset_max = @index_first,@index_last
     
                while offset_min <= offset_max
                    offset_mid =  offset_min + (offset_max - offset_min) / 14*7
                    mid = read_long(offset_mid)
     
                    if ip_long < mid
                        offset_max = offset_mid - 7
                    elsif ip_long == mid
                        return read_offset(offset_mid+4)
                    else
                        offset_min = offset_mid + 7
                    end
                end
     
                return read_offset(offset_max+4)
        end
     
        #读取字符串
        def read_str(position)
            @file.seek position
            str = []
            while c = @file.getc
              break if str.size > 60 #地址不会太长，防止有异常数据
              break if c == "\0"  #地址字符串以\0结尾
              str << c
            end
            str.join ''
        end
     
        #根据IP查找地址
        def find_ip_location(ip)
            offset = find_str_offset(ip2long(ip))#读取具体数据在记录区的偏移
            @location = {}
            case read_mode(offset+4)
            when 1
          str_offset = read_offset(offset+4+1) #读取字符串存储位置偏移（4是IP值，1是模式）
          if read_mode(str_offset)==2 then
            country_offset = read_offset(str_offset+1)
            @location[:country] = read_str country_offset
            @location[:area] = read_area(str_offset+4)
          else
            @location[:country] = read_str str_offset
            @location[:area] = read_area(@file.pos)
          end
     
            when 2
                str_offset = read_offset(offset+4+1) #读取字符串存储位置偏移（4是IP值，1是模式）
                @location[:country] = read_str(str_offset)
                @location[:area] = read_area(offset+8)
            else
                @location[:country] = read_str(offset)
                @location[:area] = read_str(@file.pos)
            end
     
            @location
        end
     
        #读取记录中的地址信息
        def read_area(position)
            mode = read_mode(position)
            if mode==1 || mode==2
                offset = read_offset(position+1)
                return '' if offset==0
                return read_str(offset)
            else
                return read_str(position)
            end
        end
     
        #取得国家，UTF8编码
        def country
            Iconv.iconv('UTF-8//IGNORE','GB2312//IGNORE',@location[:country])
        end
     
        #取得地区，UTF8编码
        def area
            Iconv.iconv('UTF-8//IGNORE','GB2312//IGNORE',@location[:area])
        end
     
        #取得国家，GB2312编码
        def country_gb
            @location[:country]
        end
     
        #取得地区，GB2312编码
        def area_gb
            @location[:area]
        end
    end
end