ftpresponse.cs

ftp客服端源代码

using System;
using System.IO;
using System.Collections;
using System.Runtime.InteropServices;

namespace KCommon.Net.FTP
{
	#region COM interface IFtpResponse
	public interface IFtpResponse
	{
		string	Message {get;}
		int		Code	{get;}
	}
	#endregion

	[ClassInterface(ClassInterfaceType.None)]
	public class FtpResponse : IFtpResponse
	{
		private readonly Queue		m_responses;
		private readonly int		m_code;

		public const int InvalidCode						=  -1;
		public const int DataChannelOpenedTransferStart		= 125;
		public const int FileOkBeginOpenDataChannel			= 150;
		public const int ServiceReady						= 220;
		public const int ClosingDataChannel					= 226;
		public const int EnterPassiveMode					= 227;
		public const int RequestFileActionComplete			= 250;
		public const int UserLoggedIn						= 230;
		public const int UserAcceptedWaitingPass			= 331;
		public const int RequestFileActionPending			= 350;
		public const int ServiceUnavailable					= 421;
		public const int TransferAborted					= 426;
		

		internal FtpResponse(Stream s)
		{
			//TextReader reader	= new StreamReader(s);
			m_responses			= new Queue();
			while(true) 
			{
				string response = GetLine(s);
				try 
				{
					m_code = InvalidCode;
					m_code = int.Parse(response.Substring(0, 3));
				}
				catch 
				{
					throw new FtpException("Invalid response", this);
				}
				m_responses.Enqueue(response);
				if(response.Length >= 4 && response[3] == '-')
					continue;
				break;
			}
			if(m_code == ServiceUnavailable)
				throw new FtpServerDownException(this);
		}

		public string Message
		{
			get {return (string)m_responses.Peek();}
		}

		public Queue Respones
		{
			get {return m_responses;}
		}

		public int Code
		{
			get {return m_code;}
		}

		private char ReadAppendChar(Stream s, System.Text.StringBuilder toAppend)
		{
			char c = (char)s.ReadByte();
			toAppend.Append(c);
			return c;
		}

		private string GetLine(Stream s)
		{
			System.Text.StringBuilder buff = new System.Text.StringBuilder();

			while(true) 
			{
				while(ReadAppendChar(s, buff) != '\r');
				while(ReadAppendChar(s, buff) == '\r');
				if(buff[buff.Length-1] == '\n')
					break;
			}
			return buff.ToString();
		}
	}
}