<b>用C++ Builderw做Ftp服务器程序</b>[VC/C++编程]

#include <stdlib.h>　//Required for atoi()
#include "..\winsock.h"　//Winsock header file
#define PROG_NAME　　"Quick FTP Version 1"
#define HOST_NAME　　"NIC.DDN.MIL "　// FTP server host
#define PASSWORD　　 "PASS guest\r\n "　// Password for FTP server host
#define WINSOCK_VERSION　 0x0101　　 // Program requires Winsock version 1.1
#define DEFAULT_PROTOCOL　0　　// No protocol specified, use default
#define NO_FLAGS　0　　// No special flags specified
char szCommandBuffer[100];　// Buffer for FTP commands
LPSTR lpszFunctionName;　// Pointer for function names
UINT GetReplyCode(LPSTR lpszServerReply)
{
　 UINT nCode;　// Reply code as a number
　 char c;　// Temporary storage
　 // lpszFunctionName =　"GetReplyCode ";
　 c = *(lpszServerReply+3);　// Save the character
　 *(lpszServerReply+3) = '\0';　// Terminate the code
　 nCode = atoi((const char *)lpszServerReply);　// Convert code to number
　 *(lpszServerReply+3) = c;　// Restore the character
　 return(nCode);　// Return the reply code
}
UINT ReadFTPServerReply(SOCKET hControlChannel)
{
　 char sReceiveBuffer[1024];　// Data-storage buffer for FTP server reply
　 int iLength;　// Length of data received from FTP server

　 lpszFunctionName =　"ReadFTPServerReply ";
　　 if ((iLength = recv(hControlChannel, (LPSTR)sReceiveBuffer,
sizeof(sReceiveBuffer), NO_FLAGS)) == SOCKET_ERROR)
　　 {
　　 int iWinsockErr = WSAGetLastError();
　　 wsprintf(szCommandBuffer,"Error %d from the recv() function!! ",
iWinsockErr);
　　 MessageBeep(MB_ICONHAND);
　　 MessageBox(NULL, szCommandBuffer, lpszFunctionName,MB_OK |MB_ICONSTOP);
// Return 999 to indicate an error has occurred
　　 return(999);
}

　 sReceiveBuffer[iLength] = '\0';
　 MessageBeep(MB_ICONASTERISK);
　 MessageBox(NULL, (LPSTR)sReceiveBuffer, lpszFunctionName,MB_OK |MB_ICONINFORMATION);
　 // Extract the reply code from the server reply and return as an integer
　 return(GetReplyCode(sReceiveBuffer));
}

UINT SendFTPCommand(SOCKET hControlChannel, LPSTR szCommandBuffer)
{
　 lpszFunctionName =　"SendFTPCommand ";
　 // Send the FTP command
　 if ((send(hControlChannel, (LPSTR)szCommandBuffer,
lstrlen(szCommandBuffer), NO_FLAGS)) == SOCKET_ERROR)
{
　　 int iWinsockErr = WSAGetLastError();
　　 wsprintf(szCommandBuffer,　"Error %d from the send() function!! ",
iWinsockErr);
　　 MessageBeep(MB_ICONHAND);
　　 MessageBox(NULL, szCommandBuffer, lpszFunctionName,MB_OK |MB_ICONSTOP);
// Return 999 to indicate an error has occurred
　　 return(999);
}

　 // Read the server's reply and return the reply code as an integer
　 return(ReadFTPServerReply(hControlChannel));
}

UINT AnonymousFTPLogIn(SOCKET hControlSocket)
{
　 int nReplyCode;　// FTP server reply code
　 int iMsg = 0;　// Index subscript for FTP commands

　 lpszFunctionName =　"AnonymousFTPLogIn ";
　 char *LoginCommand[]={"USER anonymous\r\n ",PASSWORD,NULL};
　 do
　　 {
　　 nReplyCode = SendFTPCommand(hControlSocket,(LPSTR)LoginCommand[iMsg++]);
　　 }
　 while(LoginCommand[iMsg] && nReplyCode < 400);
　 return(nReplyCode);
}
SOCKET ConnectFTPControlSocket(LPSTR lpszHost)
{
　 LPHOSTENT lpHostEnt;　// Internet host information structure
　 SOCKADDR_IN sockAddr;　// Socket address structure
　 LPSERVENT lpServEnt;　// Service information structure
　 short nProtocolPort;　// Protocol port
　 int nConnect;　// Socket connection results
　 SOCKET hControlSocket;　// Control socket handle

　 lpszFunctionName =　"ConnectFTPControlSocket ";
　 if (!(lpHostEnt = gethostbyname(lpszHost)))
{
　　 int iWinsockErr = WSAGetLastError();
　　 wsprintf(szCommandBuffer,"Error #%d while resolving address for %s ",
iWinsockErr, lpszHost);
　　 MessageBeep(MB_ICONHAND);
　　 MessageBox(NULL, szCommandBuffer, lpszFunctionName,MB_OK |MB_ICONSTOP);
　　 return(INVALID_SOCKET);
}

　 if ((hControlSocket = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP))
== INVALID_SOCKET)
{
　　 int iWinsockErr = WSAGetLastError();
　　 wsprintf(szCommandBuffer,"Error #%d occurred while creating socket!! ",
iWinsockErr);
　　 MessageBeep(MB_ICONHAND);
　　 MessageBox(NULL, szCommandBuffer, lpszFunctionName,MB_OK |MB_ICONSTOP);
　　 return(INVALID_SOCKET);
}

　 lpServEnt = getservbyname( "ftp ", DEFAULT_PROTOCOL);

　 if (lpServEnt == NULL)
　　 nProtocolPort = htons(IPPORT_FTP);
　 else
　　 nProtocolPort = lpServEnt- >s_port;
　 // Define the socket address
　 sockAddr.sin_family = AF_INET;
　 sockAddr.sin_port = nProtocolPort;
　 sockAddr.sin_addr = *((LPIN_ADDR)*lpHostEnt- >h_addr_list);

　 // Connect the socket
　 if( nConnect = connect(hControlSocket, (LPSOCKADDR)&sockAddr,
sizeof(sockAddr)))
{
　　 int iWinsockErr = WSAGetLastError();
　　 wsprintf(szCommandBuffer,
　　　　 "Error #%d occurred while connecting socket!! ",
iWinsockErr);
　　 MessageBeep(MB_ICONHAND);
　　 MessageBox(NULL, szCommandBuffer, lpszFunctionName,
MB_OK |MB_ICONSTOP);
　　 return(INVALID_SOCKET);
}

　 if (ReadFTPServerReply(hControlSocket)　>= 400)
return(INVALID_SOCKET);
　 else
return(hControlSocket);
}
int PASCAL WinMain(HANDLE hInstance, HANDLE hPrevInstance,
LPSTR lpszCmdParam, int nCmdShow)
{
　 WSADATA wsaData;　// Winsock implementation details
　 SOCKET hControlChannel;　// Socket handle for the control channel
　 UINT nReplyCode;　// FTP reply code
　 lpszFunctionName =　"WinMain ";

　 if (WSAStartup(WINSOCK_VERSION, &wsaData))
{
　　 MessageBeep(MB_ICONHAND);
　　 MessageBox(NULL,　"Could not load Windows Sockets DLL. ",
lpszFunctionName, MB_OK |MB_ICONSTOP);
　　 return(NULL);
}

　 hControlChannel = ConnectFTPControlSocket((LPSTR)HOST_NAME);
　 // Note that from a DLL, here we would return
　 // our control channel handle (if valid) for
　 // use by other program modules.
　 if (hControlChannel != INVALID_SOCKET)
{
　　 // If we have a control channel, then login.
　　 nReplyCode = AnonymousFTPLogIn(hControlChannel);

　　 if (nReplyCode == 230) // User logged in; we can proceed.
{
　　　 SendFTPCommand(hControlChannel,　"QUIT\r\n ");
　　　 closesocket(hControlChannel);
}
}

　 WSACleanup();
　 MessageBeep(MB_ICONEXCLAMATION);
　 MessageBox(NULL,　"THE END!! ", PROG_NAME, MB_OK |MB_ICONEXCLAMATION);
　 return(NULL);
}