C++ Socket发送文件服务端代码

/*
**服务端代码头文件
*/

pragma comment(lib, “WS2_32”)

include

include

//#include

include

ifndef COMMONDEF_H

define COMMONDEF_H

define MAX_PACKET_SIZE 10240 // 数据包的最大长度,单位是sizeof(char)

define MAXFILEDIRLENGTH 256 // 存放文件路径的最大长度

define PORT 4096 // 端口号

define SERVER_IP “127.0.0.1” // server端的IP地址

// 各种消息的宏定义

define INVALID_MSG -1 // 无效的消息标识

define MSG_FILENAME 1 // 文件的名称

define MSG_FILELENGTH 2 // 传送文件的长度

define MSG_CLIENT_READY 3 // 客户端准备接收文件

define MSG_FILE 4 // 传送文件

define MSG_SENDFILESUCCESS 5 // 传送文件成功

define MSG_OPENFILE_ERROR 10 // 打开文件失败,可能是文件路径错误找不到文件等原因

define MSG_FILEALREADYEXIT_ERROR 11 // 要保存的文件已经存在了

class CCSDef
{
public:

pragma pack(1) // 使结构体的数据按照1字节来对齐,省空间

// 消息头struct TMSG_HEADER{    char    cMsgID;    // 消息标识    TMSG_HEADER(char MsgID = INVALID_MSG)        : cMsgID(MsgID)    {    }};// 请求传送的文件名// 客户端传给服务器端的是全路径名称// 服务器传回给客户端的是文件名struct TMSG_FILENAME : public TMSG_HEADER{    char szFileName[256];   // 保存文件名的字符数组    TMSG_FILENAME()        : TMSG_HEADER(MSG_FILENAME)    {    }};// 传送文件长度struct TMSG_FILELENGTH : public TMSG_HEADER{    long lLength;    TMSG_FILELENGTH(long length)        : TMSG_HEADER(MSG_FILELENGTH), lLength(length)     {    }};// Client端已经准备好了,要求Server端开始传送文件struct TMSG_CLIENT_READY : public TMSG_HEADER{    TMSG_CLIENT_READY()        : TMSG_HEADER(MSG_CLIENT_READY)    {    }};// 传送文件struct TMSG_FILE : public TMSG_HEADER{    union     // 采用union保证了数据包的大小不大于MAX_PACKET_SIZE * sizeof(char)    {        char szBuff[MAX_PACKET_SIZE];        struct        {            int nStart;            int nSize;            char szBuff[MAX_PACKET_SIZE - 2 * sizeof(int)];        }tFile;    };    TMSG_FILE()        : TMSG_HEADER(MSG_FILE)    {    }};// 传送文件成功struct TMSG_SENDFILESUCCESS : public TMSG_HEADER{    TMSG_SENDFILESUCCESS()        : TMSG_HEADER(MSG_SENDFILESUCCESS)    {    }};// 传送出错信息,包括:// MSG_OPENFILE_ERROR:打开文件失败// MSG_FILEALREADYEXIT_ERROR:要保存的文件已经存在了struct TMSG_ERROR_MSG : public TMSG_HEADER{    TMSG_ERROR_MSG(char cErrorMsg)        : TMSG_HEADER(cErrorMsg)    {    }};

pragma pack()

};

endif

/*
**服务端代码源文件
*/

include “SocketTransfer.h”

char g_szNewFileName[MAXFILEDIRLENGTH];
char g_szBuff[MAX_PACKET_SIZE + 1];
long g_lLength;
char* g_pBuff = NULL;

// 初始化socket库
bool InitSocket();
// 关闭socket库
bool CloseSocket();
// 解析消息进行相应的处理
bool ProcessMsg(SOCKET sClient);
// 监听Client的消息
void ListenToClient();
// 打开文件
bool OpenFile(CCSDef::TMSG_HEADER* pMsgHeader, SOCKET sClient);
// 传送文件
bool SendFile(SOCKET sClient);
// 读取文件进入缓冲区
bool ReadFile(SOCKET sClient);

int main()
{
InitSocket();
ListenToClient();
CloseSocket();

return 0;

}

void ListenToClient()
{
// 创建socket套接字
SOCKET sListen = ::socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (SOCKET_ERROR == sListen)
{
printf(“Init Socket Error!\n”);
return;
}

// 绑定socket到一个本地地址sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.S_un.S_addr = INADDR_ANY;if (::bind(sListen, (LPSOCKADDR)&sin, sizeof(sockaddr_in)) == SOCKET_ERROR){    printf("Bind Error!\n");    return;}// 设置socket进入监听状态if (::listen(sListen, 10) == SOCKET_ERROR){    printf("Listen Error!\n");    return;}printf("Listening To Client...\n");// 循环接收client端的连接请求sockaddr_in ClientAddr;int nAddrLen = sizeof(sockaddr_in);SOCKET sClient;while (INVALID_SOCKET == (sClient = ::accept(sListen, (sockaddr*)&ClientAddr, &nAddrLen))){}while (true == ProcessMsg(sClient)){}// 关闭同客户端的连接::closesocket(sClient);::closesocket(sListen);

}

bool InitSocket()
{
// 初始化socket dll
WSADATA wsaData;
WORD socketVersion = MAKEWORD(2, 2);
if (::WSAStartup(socketVersion, &wsaData) != 0)
{
printf(“Init socket dll error\n”);
return false;
}

return true;

}

bool CloseSocket()
{
// 释放winsock库
::WSACleanup();

if (NULL != g_pBuff){    delete [] g_pBuff;    g_pBuff = NULL;}return true;

}

bool ProcessMsg(SOCKET sClient)
{
int nRecv = ::recv(sClient, g_szBuff, MAX_PACKET_SIZE + 1, 0);
if (nRecv > 0)
{
g_szBuff[nRecv] = ‘\0’;
}

// 解析命令CCSDef::TMSG_HEADER* pMsgHeader = (CCSDef::TMSG_HEADER*)g_szBuff;switch (pMsgHeader->cMsgID){case MSG_FILENAME:    // 文件名    {        OpenFile(pMsgHeader, sClient);    }    break;case MSG_CLIENT_READY:   // 客户端准备好了,开始传送文件    {        SendFile(sClient);    }    break;case MSG_SENDFILESUCCESS: // 传送文件成功    {        printf("Send File Success!\n");        return false;    }    break;case MSG_FILEALREADYEXIT_ERROR: // 要保存的文件已经存在了    {        printf("The file reay to send already exit!\n");        return false;    }    break;}return true;

}

bool ReadFile(SOCKET sClient)
{
if (NULL != g_pBuff)
{
return true;
}

// 打开文件FILE *pFile;if (NULL == (pFile = fopen(g_szNewFileName, "rb")))   // 打开文件失败{    printf("Cannot find the file, request the client input file name again\n");    CCSDef::TMSG_ERROR_MSG tMsgErrorMsg(MSG_OPENFILE_ERROR);    ::send(sClient, (char*)(&tMsgErrorMsg), sizeof(CCSDef::TMSG_ERROR_MSG), 0);    return false;}// 把文件的长度传回到client去fseek(pFile, 0, SEEK_END);g_lLength = ftell(pFile);printf("File Length = %d\n", g_lLength);CCSDef::TMSG_FILELENGTH tMsgFileLength(g_lLength);::send(sClient, (char*)(&tMsgFileLength), sizeof(CCSDef::TMSG_FILELENGTH), 0);// 处理文件全路径名,把文件名分解出来char szDrive[_MAX_DRIVE], szDir[_MAX_DIR], szFname[_MAX_FNAME], szExt[_MAX_EXT];_splitpath(g_szNewFileName, szDrive, szDir, szFname, szExt);strcat(szFname,szExt);CCSDef::TMSG_FILENAME tMsgFileName;strcpy(tMsgFileName.szFileName, szFname);printf("Send File Name: %s\n", tMsgFileName.szFileName);::send(sClient, (char*)(&tMsgFileName), sizeof(CCSDef::TMSG_FILENAME), 0);// 分配缓冲区读取文件内容g_pBuff = new char[g_lLength + 1];if (NULL == g_pBuff){    return false;}fseek(pFile, 0, SEEK_SET);fread(g_pBuff, sizeof(char), g_lLength, pFile);g_pBuff[g_lLength] = '\0';fclose(pFile);return true;

}

// 打开文件
bool OpenFile(CCSDef::TMSG_HEADER* pMsgHeader, SOCKET sClient)
{
CCSDef::TMSG_FILENAME* pRequestFilenameMsg = (CCSDef::TMSG_FILENAME*)pMsgHeader;

// 对文件路径名进行一些处理char *p1, *p2;for (p1 = pRequestFilenameMsg->szFileName, p2 = g_szNewFileName;    '\0' != *p1;    ++p1, ++p2){    if ('\n' != *p1)    {        *p2 = *p1;    }    if ('\\' == *p2)    {        *(++p2) = '\\';    }}*p2 = '\0';ReadFile(sClient);return true;

}

// 传送文件
bool SendFile(SOCKET sClient)
{
if (NULL == g_pBuff)
{
ReadFile(sClient);
}

int nPacketBufferSize = MAX_PACKET_SIZE - 2 * sizeof(int); // 每个数据包存放文件的buffer大小// 如果文件的长度大于每个数据包所能传送的buffer长度那么就分块传送for (int i = 0; i < g_lLength; i += nPacketBufferSize){      CCSDef::TMSG_FILE tMsgFile;    tMsgFile.tFile.nStart = i;    if (i + nPacketBufferSize + 1> g_lLength)    {        tMsgFile.tFile.nSize = g_lLength - i;    }    else    {        tMsgFile.tFile.nSize = nPacketBufferSize;    }    //printf("start = %d, size = %d\n", tMsgFile.tFile.nStart, tMsgFile.tFile.nSize);    memcpy(tMsgFile.tFile.szBuff, g_pBuff + tMsgFile.tFile.nStart, tMsgFile.tFile.nSize);    ::send(sClient, (char*)(&tMsgFile), sizeof(CCSDef::TMSG_FILE), 0);    Sleep(0.5);}delete [] g_pBuff;g_pBuff = NULL;return true;

}