SDK之SOCKET服务端
#include
#include
#include
#pragma comment(lib, "ws2_32.lib")
/*常量*/
#define DEFAULT_PORT "1000" //端口
#define MAX_REQUEST 1024 //接收数据的缓存
#define BUF_SIZE 4096 //发送数据缓存
/************************
* CommuncationThread
* 功能：用于接收和发送数据的线程
* 为每个连接客户端创建一个数据发送的线程
* 可以使用多个客户端同时连接到服务端
* 参数：lpParameter、SOCKET
*************************/
DWORD WINAPI CommunicationThread(
LPVOID lpParameter
)
{
DWORD dwTid = GetCurrentThreadId();
//获得参数
SOCKET socket = (SOCKET) lpParameter;
//接收数据分配空间
LPSTR szRequest = (char *)HeapAlloc(
GetProcessHeap(),
0 ,
MAX_REQUEST);
int iResult;
int bytesSent; //用于保存send的返回值，即实际发送的数据的大小
//接收数据
iResult = recv(socket,//socket
szRequest, //接收缓存
MAX_REQUEST, //缓存大小
0); //无标志
if(iResult == 0) //接收数据失败，连接关闭
{
printf("Connection closing....\n");
HeapFree(GetProcessHeap(), 0 , szRequest);
closesocket(socket);
return 1;
}
else if(iResult == SOCKET_ERROR) //接收数据失败，Socket错误
{
printf("recv faild:%d\n",WSAGetLastError());
HeapFree(GetProcessHeap(), 0 , szRequest);
closesocket(socket);
return 1;
}
else if(iResult > 0) //接收数据成功
{
//显示接收到的数据
printf("\tCommunicationThread(%d)\tBytes received:%d\n",dwTid,iResult);
printf("\tCommunicationThread(%d)\trequest string is:%s\n",dwTid,szRequest);
//如果接收到的数据是“download file”
if(lstrcmpi(szRequest,"download file") == 0)
{
//读取文件 download.txt 将发送
HANDLE hFile;
LPVOID lpReadBuf; //发送缓存
DWORD dwBytesRead;
DWORD dwFileSize;
DWORD dwSendFile = 0;
hFile = CreateFile("download.txt",
GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if(hFile == INVALID_HANDLE_VALUE)
{
printf("\tCommunicationThread\tCould not open file(error %d)\n",
GetLastError());
send(socket,"error",6,0);
closesocket(socket);
return 1;
}
//分配发送数据的缓存
lpReadBuf = HeapAlloc(GetProcessHeap(), 0 , BUF_SIZE);
//获得文件大小
dwFileSize = GetFileSize(hFile,NULL);
//循环发送
while(1)
{
//读文件到缓存
if(!ReadFile(hFile, lpReadBuf , BUF_SIZE ,&dwBytesRead,NULL))
{
printf("\tCommunicationThread\t Could not read file(error %d)\n",GetLastError());
closesocket(socket);
CloseHandle(hFile);
return 1;
}
//发送读取的文件数据
bytesSent = send(socket,
(const char*)lpReadBuf,
dwBytesRead,
0);
if(bytesSent == SOCKET_ERROR)
{
printf("\tCommunicationThread\tsend error %d\n",
GetLastError());
closesocket(socket);
CloseHandle(hFile);
return 1;
}
//显示发送数据的大小
printf("\tCommunicationThread(%d)\tsend %d Bytes\n",dwTid,bytesSent);
//累加已发送的大小
dwSendFile = dwSendFile +dwBytesRead;
//如果所有数据已发送
if(dwSendFile == dwFileSize)
{
printf("\tCommunicationThread\tFile download ok\n");
break;//退出循环
}
}
//释放内存、关闭连接、关闭文件
HeapFree(GetProcessHeap(), 0 , lpReadBuf);
CloseHandle(hFile);
closesocket(socket);
}
//如果接收到的数据是 “get information”
else if(lstrcmpi(szRequest, "get information") == 0)
{
//发送数据
bytesSent = send(socket, //socket
"this is information",//数据
lstrlen("this is information") + 1,//数据长度
0); //标志
//判断是否成功
if(bytesSent == SOCKET_ERROR)
{
printf("\tCommunicationThread\tsend error %d\n",WSAGetLastError());
closesocket(socket);
return 1;
}
printf("\tCommunicationThread(%d)\tsend %d Bytes\n",dwTid,bytesSent);
}
else //收到未知数据
{
printf("unreferenced request\n");
}
}
//释放接收数据缓存，关闭Socket
HeapFree(GetProcessHeap(), 0 ,szRequest);
closesocket(socket);
return 0;
}
/*********************
* int _cdecl main(void)
* 功能 Socket服务端程序
**********************/
int _cdecl main(void)
{
WSADATA wsaData;
SOCKET ListenSocket = INVALID_SOCKET; //监听Socket
SOCKET ClientSocket = INVALID_SOCKET; //连接Scoket
struct addrinfo *result = NULL,hints;
int iResult; //保存返回结果
//初始化WinSocke,保证Ws_32.dll已经加载
iResult = WSAStartup(MAKEWORD(2,2),&wsaData);
if(iResult !=0 )
{
printf("WSAStartup failed: %d\n",iResult);
return 1;
}
//地址
ZeroMemory(&hints, sizeof(hints));
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
hints.ai_flags = AI_PASSIVE;
//获取主机地址，保证网络协议可用
iResult = getaddrinfo(NULL, //本机
DEFAULT_PORT, //端口
&hints, //使用的网络协议、连接类型
&result); //结果
if(iResult !=0 )
{
printf("getaddrinfo failed: %d\n",iResult);
WSACleanup();
return 1;
}
//创建Socket，用于监听
ListenSocket = socket(result->ai_family , //网络协议、AF_INEF，Ipv4
result->ai_socktype , //类型，SOCK_STREAM
result->ai_protocol ); //通信协议，TCP
if(ListenSocket == INVALID_SOCKET)
{
printf("socket failed: %ld\n",WSAGetLastError());
freeaddrinfo(result);
return 1;
}
//绑定到端口
iResult = bind(ListenSocket,result->ai_addr ,(int)result->ai_addrlen );
if(iResult == SOCKET_ERROR)
{
printf("bind failed: %d\n",WSAGetLastError());
freeaddrinfo(result);
WSACleanup();
return 1;
}
printf("bind\n");
freeaddrinfo(result); //result 不再使用
//开始监听
iResult = listen(ListenSocket,SOMAXCONN);
printf("start listen......\n");
if(iResult == SOCKET_ERROR)
{
printf("bind failed: %d\n",WSAGetLastError());
freeaddrinfo(result);
WSACleanup();
return 1;
}
while(1)
{
//接收客户端的连接，accept函数会等待，直到连接建立
printf("ready to accept \n");
ClientSocket =accept(ListenSocket,NULL,NULL);
//accept 函数返回，说明已经有客户端连接
//返回连接Socket
printf("accept a connection\n");
if(ClientSocket == INVALID_SOCKET)
{
printf("accept failed: %d\n",WSAGetLastError());
closesocket(ListenSocket);
break; //等待连接错误，退出循环
}
//为每一个连接创建一个数据发送的接收线程
//使服务端又可以立即接收其他客户的连接
if(!CreateThread(NULL,
0,
CommunicationThread,//线程函数
(LPVOID)ClientSocket,//将Socket作为参数
0,
NULL))
{
printf("Create Thread error (%d)",GetLastError());
break;
}
}
//循环退出，释放DLL
WSACleanup();
return 0;
}