public long PrepareToWrite(long file_size, string file_hash)
{
long current_size = FileCommon.GetSize(_file_name);
if (current_size >= file_size) //seems need not to transmit
{
return(-1);
}
if (current_size == 0) //create new file and new information record file
{
_file_stream = new FileStream(_file_name, FileMode.OpenOrCreate, FileAccess.Write);
_file_information_stream = new FileStream(_file_information_record, FileMode.OpenOrCreate, FileAccess.ReadWrite);
_file_information_writer = new StreamWriter(_file_information_stream);
_file_information_writer.WriteLine(String.Format("{0} {1} {2}", file_hash, file_size, 0));
}
else if (current_size > 0 && current_size < file_size) //compare current file information to lastest record information
{
_file_information_stream = new FileStream(_file_information_record, FileMode.Open, FileAccess.ReadWrite);
_file_information_writer = new StreamWriter(_file_information_stream);
string[] info_list;
StreamReader info_reader = new StreamReader(_file_information_stream);
info_list = info_reader.ReadLine().Split();
if (info_list.Length != 3 || info_list[0] != file_hash || Convert.ToInt64(info_list[1]) != file_size)
{
return(-1);
}
else
{
_file_stream = new FileStream(_file_name, FileMode.Append, FileAccess.Write);
_file_information_stream.Seek(0, SeekOrigin.Begin);
}
}
_sha256_str = file_hash;
_total_size = file_size;
_offset = current_size;
return(current_size);
}
public static async Task <string> Resolve(string input_line)
{
string[] input_array = input_line.Split();
string command = input_array[0];
if (command == "retrieve")
{
if (input_array.Length == 3)
{
return("store " + input_array[1] + " " + input_array[2]);
}
else
{
return("error number of parameters in retrieve command.");
}
}
else if (command == "store")
{
if (input_array.Length == 3 && File.Exists(input_array[1]))
{
return("upload " + input_array[1] + " " + input_array[2]
+ " " + FileCommon.GetSize(input_array[1]) + " " + FileCommon.ComputeHash(input_array[1]));
}
else
{
return("error number of parameters in store command.");
}
}
else if (command == "upload")
{
if (input_array.Length == 5 && Convert.ToInt64(input_array[3]) > 0)
{
FileReceive fileReceive = new FileReceive(input_array[2]);
long seek_position = fileReceive.PrepareToWrite(Convert.ToInt64(input_array[3]), input_array[4]);
if (seek_position >= 0)
{
IPEndPoint localPoint = fileReceive.InitAndGetLocalEndPoint();
fileReceive.Run();
return("move " + input_array[1] + " " + input_array[2] + " "
+ seek_position + " " + localPoint.Address + " " + localPoint.Port);
}
else
{
return("error file already exists");
}
}
else
{
return("error file size");
}
}
else if (command == "move")
{
FileSend.SendFile(input_array[1], Convert.ToInt64(input_array[3]),
input_array[4], Convert.ToInt32(input_array[5]));
return(null);
}
else if (command == "error")
{
return(null);
}
else
{
return("error invalid commandline");
}
}