#include <Winsock2.h>
#include <windows.h>
#include <malloc.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
 
#pragma comment (lib,"ws2_32")
#define uPort 80
#define MAX_BUFFER   100000
#define SENDBLOCK   200000
#define SERVERNAME   "AcIDSoftWebServer/0.1b"
#define FileName   "HelloWorld.html"
 
typedef struct _NODE_ 
{
 SOCKET s;
 sockaddr_in Addr;
 _NODE_* pNext;
 
}Node,*pNode;
 
 
//多线程处理多个客户端的连接
typedef struct _THREAD_
{
 DWORD ThreadID;
 HANDLE hThread;
 _THREAD_* pNext;
}Thread,*pThread;
 
pNode pHead = NULL;
pNode pTail = NULL;
pThread pHeadThread = NULL;
pThread pTailThread = NULL;
 
bool InitSocket();//线程函数
DWORD WINAPI AcceptThread(LPVOID lpParam);
DWORD WINAPI ClientThread(LPVOID lpParam);
bool IoComplete(char* szRequest);     //数据包的校验函数
bool AddClientList(SOCKET s,sockaddr_in addr);
bool AddThreadList(HANDLE hThread,DWORD ThreadID);
bool ParseRequest(char* szRequest, char* szResponse, BOOL &bKeepAlive);
 
//我们存放Html文件的目录
char HtmlDir[512]={0};
 
void main()
{
 if (!InitSocket())
 {
  printf("InitSocket Error\n");
  return;
 }
 
 GetCurrentDirectory(512,HtmlDir);
 
 strcat(HtmlDir,"\\HTML\\");
 
 strcat(HtmlDir,FileName);
 //启动一个接受线程
 HANDLE hAcceptThread = CreateThread(NULL,0,AcceptThread,NULL,0,NULL);
 
 //在这里我们使用事件模型来实现我们的Web服务器
 //创建一个事件
 WaitForSingleObject(hAcceptThread,INFINITE);
}
 
DWORD WINAPI AcceptThread(LPVOID lpParam)   //接收线程
{
 //创建一个监听套接字
 SOCKET sListen = WSASocket(AF_INET,SOCK_STREAM,0,NULL,0,WSA_FLAG_OVERLAPPED); //使用事件重叠的套接字
 if (sListen==INVALID_SOCKET)
 {
  printf("Create Listen Error\n");
  return -1; 
 }
 //初始化本服务器的地址
 sockaddr_in LocalAddr;
 LocalAddr.sin_addr.S_un.S_addr = INADDR_ANY;
 LocalAddr.sin_family = AF_INET;
 LocalAddr.sin_port = htons(uPort);
 //绑定套接字 80端口
 int Ret = bind(sListen,(sockaddr*)&LocalAddr,sizeof(LocalAddr));
 if (Ret==SOCKET_ERROR)
 {
  printf("Bind Error\n");
  return -1;
 }
 //监听
 listen(sListen,5);
 //创建一个事件
 WSAEVENT Event = WSACreateEvent();
 if (Event==WSA_INVALID_EVENT)
 {
  printf("Create WSAEVENT Error\n");
  closesocket(sListen);
  CloseHandle(Event);     //创建事件失败 关闭套接字 关闭事件
  return -1;
 }
 //将我们的监听套接字与我们的事件进行关联属性为Accept
 WSAEventSelect(sListen,Event,FD_ACCEPT);
 WSANETWORKEVENTS NetWorkEvent;
 sockaddr_in ClientAddr;
 int nLen = sizeof(ClientAddr);
 DWORD dwIndex = 0;
 while (1)
 {
  dwIndex = WSAWaitForMultipleEvents(1,&Event,FALSE,WSA_INFINITE,FALSE);
  dwIndex = dwIndex - WAIT_OBJECT_0;
  if (dwIndex==WSA_WAIT_TIMEOUT||dwIndex==WSA_WAIT_FAILED)
  {
   continue;
  }
  //如果有真正的事件我们就进行判断
  WSAEnumNetworkEvents(sListen,Event,&NetWorkEvent);
  ResetEvent(&Event);   //
  if (NetWorkEvent.lNetworkEvents == FD_ACCEPT)
  {
   if (NetWorkEvent.iErrorCode[FD_ACCEPT_BIT]==0)
   {
    //我们要为新的连接进行接受并申请内存存入链表中
    SOCKET sClient = WSAAccept(sListen, (sockaddr*)&ClientAddr, &nLen, NULL, NULL);
    if (sClient==INVALID_SOCKET)
    {
     continue;
    }
    else
    {
     //如果接收成功我们要把用户的所有信息存放到链表中
     if (!AddClientList(sClient,ClientAddr))
     {
      continue;
     }  
    }
   }
  }
 }
 return 0;
}
 
DWORD WINAPI ClientThread(LPVOID lpParam)
{
 //我们将每个用户的信息以参数的形式传入到该线程
 pNode pTemp = (pNode)lpParam;
 SOCKET sClient = pTemp->s; //这是通信套接字
 WSAEVENT Event = WSACreateEvent(); //该事件是与通信套接字关联以判断事件的种类
 WSANETWORKEVENTS NetWorkEvent;
 char szRequest[1024]={0}; //请求报文
 char szResponse[1024]={0}; //响应报文
 BOOL bKeepAlive = FALSE; //是否持续连接
 if(Event == WSA_INVALID_EVENT)
 {
  return -1;
 }
 int Ret = WSAEventSelect(sClient, Event, FD_READ | FD_WRITE | FD_CLOSE); //关联事件和套接字
 DWORD dwIndex = 0;
 while (1)
 {
  dwIndex = WSAWaitForMultipleEvents(1,&Event,FALSE,WSA_INFINITE,FALSE);
  dwIndex = dwIndex - WAIT_OBJECT_0;
  if (dwIndex==WSA_WAIT_TIMEOUT||dwIndex==WSA_WAIT_FAILED)
  {
   continue;
  }
  // 分析什么网络事件产生
  Ret = WSAEnumNetworkEvents(sClient,Event,&NetWorkEvent);
  //其他情况
  if(!NetWorkEvent.lNetworkEvents)
  {
   continue;
  }
  if (NetWorkEvent.lNetworkEvents & FD_READ) //这里很有意思的
  {
    DWORD NumberOfBytesRecvd;
    WSABUF Buffers;
    DWORD dwBufferCount = 1;
    char szBuffer[MAX_BUFFER];
    DWORD Flags = 0;
    Buffers.buf = szBuffer;
    Buffers.len = MAX_BUFFER;
    Ret = WSARecv(sClient,&Buffers,dwBufferCount,&NumberOfBytesRecvd,&Flags,NULL,NULL);
    //我们在这里要检测是否得到的完整请求
    memcpy(szRequest,szBuffer,NumberOfBytesRecvd);
    if (!IoComplete(szRequest)) //校验数据包
    {
     continue;
    }
    if (!ParseRequest(szRequest, szResponse, bKeepAlive)) //分析数据包
    {
     //我在这里就进行了简单的处理
     continue;
    }
    DWORD NumberOfBytesSent = 0;
    DWORD dwBytesSent = 0;
    //发送响应到客户端
    do
    {
     Buffers.len = (strlen(szResponse) - dwBytesSent) >= SENDBLOCK ? SENDBLOCK : strlen(szResponse) - dwBytesSent; 
     Buffers.buf = (char*)((DWORD)szResponse + dwBytesSent);  
     Ret = WSASend(
      sClient,            
      &Buffers,          
      1,         
      &NumberOfBytesSent,
      0,           
      0,       
      NULL);  
     if(SOCKET_ERROR != Ret)
      dwBytesSent += NumberOfBytesSent;
    }
    while((dwBytesSent < strlen(szResponse)) && SOCKET_ERROR != Ret); 
  }
 
  if(NetWorkEvent.lNetworkEvents & FD_CLOSE)
  {
    //在这里我没有处理，我们要将内存进行释放否则内存泄露
  }
 }
 return 0;
}
 
bool InitSocket()
{
 WSADATA wsadata;
 if (WSAStartup(MAKEWORD(2,2),&wsadata)==0)    //使用Socket前必须调用 参数 作用 返回值
 {
  return true;
 }
 return false;
}
 
bool AddClientList(SOCKET s,sockaddr_in addr)
{
 pNode pTemp = (pNode)malloc(sizeof(Node));
 HANDLE hThread = NULL;
 DWORD ThreadID = 0;
 if (pTemp==NULL)
 {
  printf("No Memory\n");
  return false;
 }
 else
 {
  pTemp->s = s;
  pTemp->Addr = addr;
  pTemp->pNext = NULL;
  if (pHead==NULL)
  {
   pHead = pTail = pTemp;
  }
  else
  {
   pTail->pNext = pTemp;
   pTail = pTail->pNext;
  }
  //我们要为用户开辟新的线程
  hThread = CreateThread(NULL,0,ClientThread,(LPVOID)pTemp,0,&ThreadID);
  if (hThread==NULL)
  {
   free(pTemp);
   return false;
  }
  if (!AddThreadList(hThread,ThreadID))
  {
   free(pTemp);
   return false;
  }
 }
 return true;
}
 
bool AddThreadList(HANDLE hThread,DWORD ThreadID)
{
 pThread pTemp = (pThread)malloc(sizeof(Thread)); 
 if (pTemp==NULL)
 {
  printf("No Memory\n"); 
  return false;
 }
 else
 {
  pTemp->hThread = hThread;
  pTemp->ThreadID = ThreadID;
  pTemp->pNext = NULL; 
  if (pHeadThread==NULL)
  {
   pHeadThread = pTailThread = pTemp;
  } 
  else
  {
   pTailThread->pNext = pTemp;  
   pTailThread = pTailThread->pNext;
  }
 }
 return true;
}
 
//校验数据包
bool IoComplete(char* szRequest)
{
 char* pTemp = NULL;   //定义临时空指针
 int nLen = strlen(szRequest); //请求数据包长度
 pTemp = szRequest;   
 pTemp = pTemp+nLen-4; //定位指针
 if (strcmp(pTemp,"\r\n\r\n")==0)   //校验请求头部行末尾的回车控制符和换行符以及空行
 {
  return true;
 }
 return false;
}
 
//分析数据包
bool ParseRequest(char* szRequest, char* szResponse, BOOL &bKeepAlive)
{
 char* p = NULL;
 p = szRequest;
 int n = 0;
 char* pTemp = strstr(p," "); //判断字符串str2是否是str1的子串。如果是，则该函数返回str2在str1中首次出现的地址；否则，返回NULL。
 n = pTemp - p;    //指针长度
// pTemp = pTemp + n - 1; //将我们的指针下移
 //定义一个临时的缓冲区来存放我们
 char szMode[10]={0};
 char szFileName[10]={0};
 memcpy(szMode,p,n);   //将请求方法拷贝到szMode数组中
 if (strcmp(szMode,"GET")==0)  //一定要将Get写成大写
 { 
 //获取文件名
  pTemp = strstr(pTemp," ");
  pTemp = pTemp + 1;   //只有调试的时候才能发现这里的秘密
  memcpy(szFileName,pTemp,1);
  if (strcmp(szFileName,"/")==0)
  {
   strcpy(szFileName,FileName);
  }
  else
  {
   return false;
  }
 }
 else
 {
  return false;
 }
 // 分析链接类型
 pTemp = strstr(szRequest,"\nConnection: Keep-Alive");  //协议版本
 n = pTemp - p;
 if (p>0)
 {
  bKeepAlive = TRUE;
 }
 else  //这里的设置是为了Proxy程序的运行
 {
  bKeepAlive = TRUE;
 }
 //定义一个回显头
 char pResponseHeader[512]={0};
 char szStatusCode[20]={0};
 char szContentType[20]={0};
 strcpy(szStatusCode,"200 OK");
 strcpy(szContentType,"text/html");
 char szDT[128];
 struct tm *newtime;
 long ltime;
 time(&ltime);
 newtime = gmtime(&ltime);
 strftime(szDT, 128,"%a, %d %b %Y %H:%M:%S GMT", newtime);
 //读取文件
 //定义一个文件流指针
 FILE* fp = fopen(HtmlDir,"rb");
 fpos_t lengthActual = 0;
 int length = 0;
 char* BufferTemp = NULL;
 if (fp!=NULL)
 {
  // 获得文件大小
  fseek(fp, 0, SEEK_END);
  fgetpos(fp, &lengthActual);
  fseek(fp, 0, SEEK_SET);
  //计算出文件的大小后我们进行分配内存
  BufferTemp = (char*)malloc(sizeof(char)*((int)lengthActual));
  length = fread(BufferTemp,1,(int)lengthActual,fp);
  fclose(fp);
  // 返回响应
  sprintf(pResponseHeader, "HTTP/1.0 %s\r\nDate: %s\r\nServer: %s\r\nAccept-Ranges: bytes\r\nContent-Length: %d\r\nConnection: %s\r\nContent-Type: %s\r\n\r\n",
   szStatusCode, szDT, SERVERNAME, length, bKeepAlive ? "Keep-Alive" : "close", szContentType);   //响应报文
 }
 //如果我们的文件没有找到我们将引导用户到另外的错误页面
 else
 {
 }
 strcpy(szResponse,pResponseHeader);
 strcat(szResponse,BufferTemp);
 free(BufferTemp);
 BufferTemp = NULL;
 return true;
}