#ifndef BTSTREAM_H#define BTSTREAM_H#include "./def.h"#include "./bufio.h"#ifdef WINDOWS#include "Winsock2.h"#else#include "unistd.h"#endif#include "rate.h"size_t get_nl(char *from);void set_nl(char *to, size_t from);class btStream{private:  SOCKET sock, sock_was;  size_t m_oldbytes;public:  BufIo in_buffer;  BufIo out_buffer;  btStream() { sock = sock_was = INVALID_SOCKET; m_oldbytes = 0; }  ~btStream() { if( INVALID_SOCKET != sock) CLOSE_SOCKET(sock); }  SOCKET GetSocket() { return (INVALID_SOCKET==sock) ? sock_was : sock; }  void SetSocket(SOCKET sk){ sock = sk; }  void Close(){    if( INVALID_SOCKET != sock ){      CLOSE_SOCKET(sock);      sock_was = sock;      sock = INVALID_SOCKET;    }    in_buffer.Close();    out_buffer.Close();  }  ssize_t PickMessage(); //移除接收緩存中的一條消息  ssize_t Feed();  ssize_t Feed(Rate *rate);  ssize_t Feed(size_t limit, Rate *rate);  int HaveMessage();  // 返回值 1: 緩存中有消息 0: 暫無消息 -1: 失敗  char PeekMessage();  ssize_t Send_Keepalive();  ssize_t Send_State(unsigned char state);  ssize_t Send_Have(size_t idx);  ssize_t Send_Piece(size_t idx,size_t off,char *piece_buf,size_t len);  ssize_t Send_Bitfield(char *bit_buf,size_t len);  ssize_t Send_Request(size_t idx,size_t off,size_t len);  ssize_t Send_Cancel(size_t idx,size_t off,size_t len);  ssize_t Send_Buffer(char *buf,size_t len);  ssize_t Flush();};#endif