c++实现一个高并发服务器（三）服务器

简介：

前面我实现了一个完整的动态线程池，接下来我要使用该线程池来实现服务器。下面介绍一下本服务器的基本特点。

• 本服务器利用linux提供的epoll io复用技术来实现高并发访问
• 对于客户端提供指定目录下文件的下载功能
• 利用线程池来处理客户端的请求

前文
c++实现一个高并发服务器（二）线程池
c++实现一个高并发服务器（一）任务队列

组件

• 服务器类 Server

成员	简介
Server()	创建线程池
~Server()	释放线程池
run()	进行端口和工作目录的设定，调用epollrun（）
initListenFd()	创建socket，绑定地址端口，监听等一些列操作
epollRun(int lfd)	创建epoll,将服务器fd加入监听，循环监听
ThreadPool *m_pool	线程池指针

• 文件信息类 FdInfo
  用来封装一个文件描述符

成员	简介
int fd	文件描述符
int epfd	epoll描述符
pthread_t tid	对应的线程号

• 一些用到的static 函数

函数	简介
static void* acceptClient(void * arg);	当epoll中监听服务器fd可读就代表有新的客户端连接，客户端连接处理函数，将新的客户端fd加入监听
static void* recvHttpRequest(void* arg);	参数强制转换为FdInfo,从此fd中读取http请求，读取完毕后调用解析函数，即下面的函数
static int parseRequestLine(const char*line,int cfd);	利用正则表达式将http请求中的method,path,protocol获取，将path转换为相对路径，发送http响应头和对应文件
static int sendHeadMsg(int cfd,int status,const char* descr,const char* type,int length);	发送响应头，包括版本，状态码，状态码描述，content-type和content-length
static int sendFile(const char* fileName,int cfd);	将对应文件发送给对应客户端fd
static int sendDir(const char* dirName,int cfd);	使用一个文件名链表，获取当前目录所有文件名，根据每个文件的文件属性编写响应报文（检查是不是子目录），最后发送响应报文
static const char* getFileType(const char *name);	解析文件名称，根据后缀名返回对应的html语句
static int hexToDec(char c);	16进制的字符转10进制数字
static void decodeMsg(char * to,char * from);	将16进制的http请求报文转换为10进制

流程图

Server.h

#pragma once

#include
#include"ThreadPool.h"
#include"TaskQueue.h"

struct FdInfo{
	int fd;
	int epfd;
	pthread_t tid;
};
class Server{
public:
	Server();
	~Server();

	int run(int argc, char* argv[]);
private:
	int initListenFd(unsigned short port);
	int epollRun(int fd);
private:
	ThreadPool *m_pool;
};

Server.cpp

#include"Server.h"
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include

static void* acceptClient(void * arg);
static void* recvHttpRequest(void* arg);

static int parseRequestLine(const char*line,int cfd);
static int sendHeadMsg(int cfd,int status,const char* descr,const char* type,int length);
static int sendFile(const char* fileName,int cfd);
static int sendDir(const char* dirName,int cfd);
static const char* getFileType(const char *name);
static int hexToDec(char c);
static void decodeMsg(char * to,char * from);

Server::Server(){
	m_pool=new ThreadPool(8,8);
}

Server::~Server(){
	if(m_pool!=nullptr){
		delete m_pool;
		m_pool=nullptr;
	}
}

int Server::run(int argc,char* argv[]){
	if(argc<3){
		printf("Please input : ./xxx port path\n");
		return -1;
	}
	unsigned short port=atoi(argv[1]);
	chdir(argv[2]);

	printf("Init listen...\n");
	int lfd=initListenFd(port);
	if(lfd==-1){
		return -1;
	}

	printf("epoll run ...\n");
	epollRun(lfd);

	return 0;
}

int Server::initListenFd(unsigned short port){

	//1.create socket 
	int lfd=socket(AF_INET, SOCK_STREAM, 0);
	if(lfd==-1){
		perror("socket");
		return -1;
	}

	//2.set addr reuse
	int opt=1;
	int ret=setsockopt(lfd, SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt));
	if(ret==-1){
		perror("setsockopt");
		return -1;
	}

	//3.bind the addr
	struct sockaddr_in addr;
	addr.sin_family = AF_INET;
	addr.sin_addr.s_addr =INADDR_ANY;
	addr.sin_port = htons(port);
	ret=bind(lfd,(struct sockaddr *)&addr,sizeof(addr));
	if(ret==-1){
		perror("bind");
		return -1;
	}

	//4.set listen
	ret=listen(lfd,128);
	if(ret==-1){
		perror("listen");
		return -1;
	}

	return lfd;
}

int Server::epollRun(int lfd){
	//1.create a epoll instance
	int epfd=epoll_create(1);
	if(epfd==-1){
		perror("eppoll_create");
		return -1;
	}

	//2.register lfd in epoll
	struct epoll_event ev;
	ev.data.fd=lfd;
	ev.events=EPOLLIN;
	int ret=epoll_ctl(epfd,EPOLL_CTL_ADD,lfd,&ev);
	if(ret==-1){
		perror("epoll_create");
		return -1;
	}

	//loop to check
	struct epoll_event evs[1024];
	int size=sizeof(evs)/sizeof(struct epoll_event);
	while(1){
		int num=epoll_wait(epfd,evs,size,-1);
		for(int i=0;i<num;++i){
			int fd=evs[i].data.fd;
			struct FdInfo* info=new struct FdInfo;
			info->fd=fd;
			info->epfd=epfd;
			if(fd==lfd){
				acceptClient(info);
				printf("acceptClient...\n");
				usleep(1);
			}else{
				printf("recvHttpRequest...\n");
				m_pool->addTask(Task(recvHttpRequest,info));
				usleep(1);
			}
		}
	}
	return 0;
}

static void * acceptClient(void* arg){
	printf("acceptClient threadId:%ld\n",pthread_self());
	struct FdInfo* info=(struct FdInfo*)arg;
	//1.establish connection
	int cfd=accept(info->fd,NULL,NULL);
	if(cfd==-1){
		perror("accept");
		return NULL;
	}

	//set cfd is noblock 
	int flag=fcntl(cfd,F_GETFL);
	flag |=O_NONBLOCK;
	fcntl(cfd,F_SETFL,flag);

	//add cfd to epoll
	struct epoll_event ev;
	ev.data.fd=cfd;
	ev.events=EPOLLIN|EPOLLET;
	int ret=epoll_ctl(info->epfd,EPOLL_CTL_ADD,cfd,&ev);
	if(ret==-1){
		perror("epoll_ctl");
		return NULL;
	}

	free(info);
	return NULL;
}


static void* recvHttpRequest(void *arg){
	printf("recvHttpRequest threadId:%ld\n",pthread_self());
	struct FdInfo* info=(struct FdInfo*)arg;

	int len=0,total=0;
	char tmp[1024]={0};
	char buf[4096]={0};
	while((len=recv(info->fd,tmp,sizeof tmp,0))>0){
		if(total+len<sizeof buf){
			memcpy(buf+total,tmp,len);
		}
		total=total+len;
	}

	if(len==-1&&errno==EAGAIN){
		parseRequestLine(buf,info->fd);
	}else if(len==0){
		epoll_ctl(info->epfd,EPOLL_CTL_DEL,info->fd,NULL);
		close(info->fd);
	}else{
		perror("recv");
	}
	free(info);
	return NULL;
}

static int parseRequestLine(const char *line ,int cfd){
	printf("pareRequestLine...\n");
	char method[12]="";
	char path[1024]="";
	char protocol[256]="";
	
	sscanf(line,"%[^ ] %[^ ] %[^ \r\n]",method,path,protocol);
	printf("before decode: [%s]  [%s]  [%s]\n",method,path,protocol);
	decodeMsg(path,path);
	printf("after decode: [%s]  [%s]  [%s]\n",method,path ,protocol);

	

	if(strcasecmp(method,"get")!=0){
		printf("not get\n");
		return -1;
	}

	char *file=NULL;
	
	//deal the static file which client asked
	if(strcmp(path,"/")==0){
		file="./";
	}else{
		file=path +1;
	}

	//get file property
	struct stat st;
	int ret=stat(file,&st);
	if(ret==-1){
		//file not exist
		sendHeadMsg(cfd,404,"Not Found",getFileType(".html"),-1);
		sendFile("404.html",cfd);
		return 0;
	}
	if(S_ISDIR(st.st_mode)){
		sendHeadMsg(cfd,200,"OK",getFileType(".html"),-1);
		sendDir(file,cfd);
	}else{
		sendHeadMsg(cfd,200,"OK",getFileType(file),st.st_size);
		sendFile(file,cfd);
	}

	return 0;

}

static int sendHeadMsg(int cfd,int status,const char* descr,const char* type,int length){
	//response line
	char buf[4096]={0};
	sprintf(buf,"HTTP/1.1 %d %s\r\n",status,descr);
	
	//response head
	sprintf(buf+strlen(buf),"content-type:%s\r\n",type);
	sprintf(buf+strlen(buf),"content-length:%d\r\n\r\n",length);

	send(cfd,buf,strlen(buf),0);
	return 0;
}

static int sendFile(const char* fileName,int cfd){
	printf("send file: %s\n",fileName);
	int fd=open(fileName,O_RDONLY);
	assert(fd>0);
	int size=lseek(fd,0,SEEK_END);
	lseek(fd,0,SEEK_SET);
	off_t offset=0;
	while(offset<size){
		//sendfile function has limitation of sending
		int ret=sendfile(cfd,fd,&offset,size-offset);
		usleep(1);
		printf("ret=%d\n",ret);
		if(ret==-1){
			if(errno==EAGAIN){
				printf("no data.../");
			}
			perror("sendfile");
		}

	}
	close(fd);
	return 0;
}

static int sendDir(const char* dirName,int cfd){
	printf("send Dir:%s\n",dirName);
	char buf[4096]={0};
	sprintf(buf,"",dirName);structdirent** namelist;//point to a pointer array//struct dirent* tmp[]int num=scandir(dirName,&namelist,NULL,alphasort);for(int i=0;i<num;i++){char*name=namelist[i]->d_name;structstat st;char subPath[1024]={0};sprintf(subPath,"%s/%s",dirName,name);stat(subPath,&st);if(S_ISDIR(st.st_mode)){sprintf(buf+strlen(buf),"%ld",
				name,name,st.st_size);}else{sprintf(buf+strlen(buf),"",
				name,name,st.st_size);}send(cfd,buf,strlen(buf),0);memset(buf,0,sizeof(buf));free(namelist[i]);}sprintf(buf,"

	 
							 
	
	
		 
		 
		
		
		
		
			
				
%s
		
			
				
%s
%ld
		
		
		

		
	
	
");
	send(cfd,buf,strlen(buf),0);

	free(namelist);
	return 0;

} 

static const char* getFileType(const char* name){
	const char *dot=strrchr(name,'.');
//judge file type by file name
	if(dot==NULL)
		return "text/plain;charset=utf-8";
	if(strcmp(dot,".html")==0||strcmp(dot,"htm")==0)
		return "text/html;charset=utf-8";
	if(strcmp(dot,".jpg")==0||strcmp(dot,".jpeg")==0)
		return "image/jpeg";
	if(strcmp(dot,".gif")==0)
		return "image/gif";
	if(strcmp(dot,".png")==0)
		return "image/png";
	if(strcmp(dot,".css")==0)
		return "text/css";
	if(strcmp(dot,"au")==0)
		return "audio/.au";
	if(strcmp(dot,".wav")==0)
		return "audio/.wav";
	if(strcmp(dot,".avi")==0)
		return "video/x-msvideo";
	if(strcmp(dot,".mov")==0||strcmp(dot,".qt")==0)
		return "video/quicktime";
	if(strcmp(dot,".mpeg")==0||strcmp(dot,".mpe")==0)
		return "video/mepeg";
	if(strcmp(dot,".mp3")==0)
		return "audio/mpeg";
	if(strcmp(dot,".vrml")==0)
		return "model/vrml";
	if(strcmp(dot,".ogg")==0)
		return "application/ogg";
	if(strcmp(dot,".pac")==0)
		return "application/x-nx-proxy-autoconfig";

	return"text/plain;charset=utf-8";
}

static int hexToDec(char c){
	if(c>='0'&&c<='9')
		return c-'0';
	if(c>='a'&&c<='f')
		return c-'a'+10;
	if(c>='A'&&c<='F')
		return c-'a'+10;

	return 0;
}

static void decodeMsg(char* to,char* from){
	for(;*from!='\0';++to,++from){
		//judge from %20 3 chars 
		if(from[0]=='%'&&isxdigit(from[1])&&isxdigit(from[2])){
		//turn hex to dec
		//3 chars become 1 char ,this original data
			*to=hexToDec(from[1])*16+hexToDec(from[2]);
			from+=2;
		}else{
			*to=*from;
		}
	}
	*to='\0';
}

main.cpp

#include
#include"Server.h"
#include
#include

int main(int argc, char **argv){
	Server server;
	return server.run(argc,argv);
	return 0;
}

测试

总结

到这里我们的高并发服务器基本上以及实现完毕了，后续还会做一些小的改进，或者添加一些新的功能。