/// <summary>
/// 从IP文件中读取指定字节并转换位long
/// </summary>
/// <param name="stream"></param>
/// <param name="bytesCount">需要转换的字节数，主意不要超过8字节</param>
/// <returns></returns>
private long ReadLongX(IpDbAccessor stream, int bytesCount)
{
var bytes = new byte[8];
stream.Read(bytes, 0, bytesCount);
return(BitConverter.ToInt64(bytes, 0));
}
///<summary>
///查找IP地址所在的绝对偏移量
///</summary>
///<param name="ip"></param>
///<returns></returns>
private long locateIP(IpDbAccessor ipFile, byte[] ip)
{
long m = 0;
int r;
var b4 = new byte[4];
//比较第一个IP项
readIP(ipFile, _startPosition, b4);
r = compareIP(ip, b4);
if (r == 0)
{
return(_startPosition);
}
else if (r < 0)
{
return(-1);
}
//开始二分搜索
for (long i = _startPosition, j = _endPosition; i < j;)
{
m = this.getMiddleOffset(i, j);
readIP(ipFile, m, b4);
r = compareIP(ip, b4);
if (r > 0)
{
i = m;
}
else if (r < 0)
{
if (m == j)
{
j -= IP_RECORD_LENGTH;
m = j;
}
else
{
j = m;
}
}
else
{
ipFile.Position = m + 4;
return(ReadLongX(ipFile, 3));//readLong3(m + 4);
}
}
ipFile.Position = m + 4;
m = ReadLongX(ipFile, 3);//readLong3(m + 4);
readIP(ipFile, m, b4);
r = compareIP(ip, b4);
if (r <= 0)
{
return(m);
}
else
{
return(-1);
}
}
///<summary>
///从当前位置读取3字节
///</summary>
///<returns></returns>
private long readLong3(IpDbAccessor ipFile)
{
long ret = 0;
ret |= Convert.ToInt64(ipFile.ReadByte() & 0xFF);
ret |= Convert.ToInt64((ipFile.ReadByte() << 8) & 0xFF00);
ret |= Convert.ToInt64((ipFile.ReadByte() << 16) & 0xFF0000);
return(ret);
}
///<summary>
///根据当前位置,读取3字节
///</summary>
///<param name="offset"></param>
///<returns></returns>
private long readLong3(IpDbAccessor ipFile, long offset)
{
long ret = 0;
ipFile.Position = offset;
ret |= Convert.ToInt64(ipFile.ReadByte() & 0xFF);
ret |= Convert.ToInt64((ipFile.ReadByte() << 8) & 0xFF00);
ret |= Convert.ToInt64((ipFile.ReadByte() << 16) & 0xFF0000);
return(ret);
}
///<summary>
///从当前位置读取四字节,此四字节是IP地址
///</summary>
///<param name="offset"></param>
///<param name="ip"></param>
private void readIP(IpDbAccessor ipFile, long offset, byte[] ip)
{
ipFile.Position = offset;
ipFile.Read(ip, 0, ip.Length);
byte tmp = ip[0];
ip[0] = ip[3];
ip[3] = tmp;
tmp = ip[1];
ip[1] = ip[2];
ip[2] = tmp;
}
/// <inheritdoc />
/// <summary>
/// 初始化
/// </summary>
/// <param name="token"></param>
/// <returns></returns>
public virtual async Task <bool> InitAsync(bool getNewDb = false, CancellationToken token = default(CancellationToken))
{
if (_init != null && !getNewDb)
{
return(_init.Value);
}
await _initLock.WaitAsync(token);
try
{
if (_init != null && !getNewDb)
{
return(_init.Value);
}
var isExist = DbFileExist(_qqwryOptions.DbPath);
if (!isExist || getNewDb)
{
await UpdateDbAsync();
}
#if DEBUG
System.Diagnostics.Debug.WriteLine("使用IP数据库{0}", _qqwryOptions.DbPath);
#endif
_qqwryDbBytes = FileToBytes(_qqwryOptions.DbPath);
var ipFile = new IpDbAccessor(_qqwryDbBytes);
_startPosition = ReadLongX(ipFile, 4);
_endPosition = ReadLongX(ipFile, 4);
//总记录数
_ipCount = Convert.ToInt32((_endPosition - _startPosition) / IP_RECORD_LENGTH + 1);
_version = null;
_init = true;
}
finally
{
_initLock.Release();
}
if (_qqwryDbBytes == null)
{
throw new InvalidOperationException("无法打开IP数据库" + _qqwryOptions.DbPath + "！");
}
return(true);
}
/// <inheritdoc />
/// <summary>
/// 初始化
/// </summary>
/// <returns></returns>
public virtual bool Init(bool getNewDb = false)
{
if (_init != null && !getNewDb)
{
return(_init.Value);
}
_initLock.Wait();
try
{
if (_init != null && !getNewDb)
{
return(_init.Value);
}
var isExist = DbFileExist(_qqwryOptions.DbPath);
if (!isExist || getNewDb)
{
UpdateDb();
}
#if DEBUG
System.Diagnostics.Debug.WriteLine(format: $"使用IP数据库{_qqwryOptions.DbPath}");
#endif
_qqwryDbBytes = FileToBytes(_qqwryOptions.DbPath);
var ipFile = new IpDbAccessor(_qqwryDbBytes);
_startPosition = ReadLongX(ipFile, 4);
_endPosition = ReadLongX(ipFile, 4);
//总记录数
_ipCount = Convert.ToInt32((_endPosition - _startPosition) / IP_RECORD_LENGTH + 1);
_version = null;
_init = true;
}
finally
{
_initLock.Release();
}
if (_qqwryDbBytes == null)
{
throw new InvalidOperationException("无法打开IP数据库" + _qqwryOptions.DbPath + "！");
}
return(true);
}
///<summary>
///取得具体信息
///</summary>
///<param name="offset"></param>
///<returns></returns>
private IpLocation getIPLocation(IpLocation loc, IpDbAccessor ipFile, long offset)
{
ipFile.Position = offset + 4;
//读取第一个字节判断是否是标志字节
byte one = (byte)ipFile.ReadByte();
if (one == REDIRECT_MODE_1)
{
//第一种模式
//读取国家偏移
long countryOffset = ReadLongX(ipFile, 3);//readLong3();
//转至偏移处
ipFile.Position = countryOffset;
//再次检查标志字节
byte b = (byte)ipFile.ReadByte();
if (b == REDIRECT_MODE_2)
{
loc.Country = readString(ipFile, ReadLongX(ipFile, 3));//readString(readLong3());
ipFile.Position = countryOffset + 4;
}
else
{
loc.Country = readString(ipFile, countryOffset);
}
//读取地区标志
loc.Area = readArea(ipFile, ipFile.Position);
}
else if (one == REDIRECT_MODE_2)
{
//第二种模式
loc.Country = readString(ipFile, ReadLongX(ipFile, 3));//readString(readLong3());
loc.Area = readArea(ipFile, offset + 8);
}
else
{
//普通模式
loc.Country = readString(ipFile, --ipFile.Position);
loc.Area = readString(ipFile, ipFile.Position);
}
return(loc);
}
///<summary>
///读取字符串
///</summary>
///<param name="offset"></param>
///<returns></returns>
private string readString(IpDbAccessor ipFile, long offset)
{
var buf = new byte[100];
ipFile.Position = offset;
int i = 0;
for (i = 0, buf[i] = (byte)ipFile.ReadByte();
buf[i] != (byte)(0); buf[++i] = (byte)ipFile.ReadByte())
{
;
}
if (i > 0)
{
return(_encodingGb2312.GetString(buf, 0, i));
}
else
{
return("");
}
}
///<summary>
///搜索IP地址搜索
///</summary>
///<param name="ip"></param>
///<returns></returns>
public IpLocation ReadLocation(IpLocation loc, string ip)
{
//将字符IP转换为字节
string[] ipSp = ip.Split('.');
if (ipSp.Length != 4)
{
throw new ArgumentOutOfRangeException("不是合法的IP地址!");
}
byte[] IP = new byte[4];
for (int i = 0; i < IP.Length; i++)
{
IP[i] = (byte)(int.Parse(ipSp[i]) & 0xFF);
}
var ipFile = new IpDbAccessor(_qqwryDbBytes);
long offset = locateIP(ipFile, IP);
if (offset != -1)
{
loc = getIPLocation(loc, ipFile, offset);
}
return(loc);
}
///<summary>
///读取地区名称
///</summary>
///<param name="offset"></param>
///<returns></returns>
private string readArea(IpDbAccessor ipFile, long offset)
{
ipFile.Position = offset;
byte one = (byte)ipFile.ReadByte();
if (one == REDIRECT_MODE_1 || one == REDIRECT_MODE_2)
{
ipFile.Position = offset + 1;
long areaOffset = ReadLongX(ipFile, 3);//readLong3(offset + 1);
if (areaOffset == 0)
{
return(unArea);
}
else
{
return(readString(ipFile, areaOffset).Replace(" CZ88.NET", ""));
}
}
else
{
return(readString(ipFile, offset).Replace(" CZ88.NET", ""));
}
}