// 获取数据信息
private Types.VirtualDataInfo GetDataInfo(long pos)
{
Types.VirtualDataInfo res = new Types.VirtualDataInfo();
res.Position = pos;
using (dpz3.File.BinaryFile file = new File.BinaryFile(workPath, System.IO.FileMode.OpenOrCreate)) {
file.Position = pos * Data_Info_Size;
// 读取Sign
try {
// 读取NextPosition
res.NextPosition = file.Read();
res.NextPosition += file.Read() * 256;
res.NextPosition += file.Read() * 256 * 256;
res.NextPosition += file.Read() * 256 * 256 * 256;
// 读取FirstChildPosition
res.Length = file.Read();
res.Length += file.Read() * 256;
} catch (Exception ex) {
throw new Exception("磁盘数据损坏", ex);
}
}
return(res);
}
// 获取数据信息
private void ReadData(ref Types.VirtualDataInfo info)
{
using (dpz3.File.BinaryFile file = new File.BinaryFile(workPath, System.IO.FileMode.OpenOrCreate)) {
file.Position = info.Position * Data_Info_Size + 6;
// 读取Sign
try {
// 读取Data
info.Data = file.Read(info.Length);
} catch (Exception ex) {
throw new Exception("磁盘数据损坏", ex);
}
}
}
// 保存数据信息
private void SaveDataInfo(Types.VirtualDataInfo info)
{
using (dpz3.File.BinaryFile file = new File.BinaryFile(workPath, System.IO.FileMode.OpenOrCreate)) {
file.Position = info.Position * Data_Info_Size;
// 读取Sign
try {
// 输出NextPosition
file.Write(GetBytesFromLong(info.NextPosition));
// 输出Length
file.Write(GetBytesFromInt(info.Length));
} catch (Exception ex) {
throw new Exception("磁盘数据损坏", ex);
}
}
}
/// <summary>
/// 保存文件
/// </summary>
/// <param name="path"></param>
/// <param name="bytes"></param>
public void SaveFile(string path, byte[] bytes)
{
// 获取文件信息
var info = GetPathInfo(path);
// 判断路径类型
if ((info.Type & Path_Type_Dir) == Path_Type_Dir)
{
throw new Exception($"\"{path}\"是文件夹");
}
// 文件不存在，则创建
if (info.Type == 0)
{
CreateFile(path);
info = GetPathInfo(path);
}
int idx = 0;
var pos = info.FirstChildPosition;
Types.VirtualDataInfo dInfo = new Types.VirtualDataInfo();
// 覆盖原有的数据段
while (pos > 0)
{
// 读取数据段
dInfo = GetDataInfo(pos);
// 判断可写入长度
int len = bytes.Length - idx;
if (len > Data_Size)
{
len = Data_Size;
}
// 拷贝数据
if (len > 0)
{
dInfo.Data = new byte[len];
Array.Copy(bytes, idx, dInfo.Data, 0, len);
idx += len;
}
else
{
dInfo.Data = new byte[0];
}
// 转移到下一个数据块
pos = dInfo.NextPosition;
// 保存数据段
dInfo.Length = len;
// 清理寻址在文件变小后可以降低文件的寻址数量，但是当文件忽大忽小时，会产生冗余存储块，不建议清理
//if (dInfo.Length < Data_Info_Size - 6) dInfo.NextPosition = 0;
SaveData(dInfo);
}
// 循环添加数据段
while (idx < bytes.Length)
{
Types.VirtualDataInfo newInfo = new Types.VirtualDataInfo();
newInfo.NextPosition = 0;
// 判断可写入长度
int len = bytes.Length - idx;
if (len > Data_Size)
{
len = Data_Size;
}
// 拷贝数据
newInfo.Data = new byte[len];
Array.Copy(bytes, idx, newInfo.Data, 0, len);
idx += len;
// 数据区块增加
diskInfo.DataBlocks++;
newInfo.Position = diskInfo.DataBlocks;
newInfo.Length = len;
// 保存磁盘信息
SaveDiskInfo();
// 保存数据段
SaveData(newInfo);
// 向文件信息或上一个数据段增加
if (info.FirstChildPosition == 0)
{
info.FirstChildPosition = newInfo.Position;
SavePathInfo(info);
}
else
{
dInfo.NextPosition = newInfo.Position;
SaveDataInfo(dInfo);
}
// 将当前段填充为缓存段
dInfo = newInfo;
}
}
