02.10 TCP之文件传输

1.思维导图

2.作业

服务器代码：

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <pthread.h>
#include <semaphore.h>
#include <wait.h>
#include <signal.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <semaphore.h>
#include <sys/msg.h>
#include <sys/shm.h>
#include <sys/un.h>
#include <sys/epoll.h>

typedef struct sockaddr_in addr_in_t;
typedef struct sockaddr addr_t;
typedef struct sockaddr_un addr_un_t;

enum Type{
    TYPE_REGIST,
    TYPE_LOGIN,
    TYPE_CHAT,
	TYPE_FILE_UPLOAD_REQUEST
};

typedef struct Pack{
	enum Type type;
	char name[20];
	char pswd[20];
	char filename[20];
	long filesize;
	char tarname[20];
	char text[1024];
}pack_t;

// 李四:你好
typedef struct User{
	char name[20];
	char pswd[20];
	int sock;
	int hasMsg; // 用来表示当前客户端是否拥有未读消息的数据：0表示不拥有，1表示拥有未读消息
	char msg[1024]; // 用来缓存针对该用户的未读消息
//	当该用户上线的时候，检索一下hasMsg是0还是1，如果是1，就将msg里面的数据发给自己
}user_t;

user_t user_arr[50] = {0};
int user_len = 0;

void read_data(int client);
void insert_user(user_t user);
int find_user(const char* username);

int main(int argc, const char *argv[])
{
	if(argc != 2){
		printf("请输入端口号\n");
		return 1;
	}



	// ./server 8888
	int port = atoi(argv[1]);// 将字符串 8888 转换成int类型port

	// 创建服务器套接字
	int server = socket(AF_INET,SOCK_STREAM,0);

	// 准备网络地址结构体：struct sockaddr_in
	addr_in_t addr = {0};
	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = inet_addr("0.0.0.0");

	// 为套接字绑定ip 和 port
	if(bind(server,(addr_t*)&addr,sizeof(addr)) == -1){
		perror("bind");
		return 1;
	}

	// 监听
	listen(server,10);
	
	// 创建监视列表
	int epfd = epoll_create1(EPOLL_CLOEXEC);


	// 将 0 和 server 存入监视列表 epfd 中
	struct epoll_event epoll_stdin = {
		.events = EPOLLIN,
		.data.fd = 0
	};

	struct epoll_event epoll_server = {
		.events = EPOLLIN,
		.data.fd = server
	};

	epoll_ctl(epfd,EPOLL_CTL_ADD,0,&epoll_stdin);
	epoll_ctl(epfd,EPOLL_CTL_ADD,server,&epoll_server);

	// 准备一个数组，用来存放所有激活的描述符
	struct epoll_event arr[50] = {0};

	while(1){
		int len = epoll_wait(epfd,arr,50,-1);
		for(int i=0;i<len;i++){
			int fd = arr[i].data.fd;// 将到底是哪个描述符激活了单独取出来
			if(fd == server){
				printf("有新客户端连接\n");
				int client = accept(server,0,0);

				struct epoll_event epoll_client = {
					.events = EPOLLIN,
					.data.fd = client
				};
				epoll_ctl(epfd,EPOLL_CTL_ADD,client,&epoll_client);


			}else if(fd == 0){
				char buf[64] = "";
				scanf("%63s",buf);
				while(getchar()!=10);
				printf("键盘输入数据:%s\n",buf);
			}else{
				read_data(fd);
			}
		}
	}
	
	return 0;
}

void insert_user(user_t user){
	user_arr[user_len] = user;
	user_len ++;
}

int find_user(const char* username){
	for(int i=0;i<user_len;i++){
		if(strcmp(username,user_arr[i].name) == 0){
			return i;
		}
	}
	return -1;
}



void read_data(int client){
	//while(1){
		pack_t pack = {0};
		int res = read(client,&pack,sizeof(pack));
		//if(res == 0){break;}
		switch(pack.type){
			case TYPE_REGIST:{
				int res = find_user(pack.name);// 根据用户发来的账号，在数组中查询是否存在
				char* msg = NULL;
				if(res == -1){ // 如果不存在返回-1
					user_t user = {0};
					strcpy(user.name,pack.name);
					strcpy(user.pswd,pack.pswd);
					insert_user(user);
					msg = "注册成功";
				}else{// 如果存在，返回这个账号在数组中的下标位置
					msg = "该账号已存在";
				}
				strcpy(pack.text,msg);
				write(client,&pack,sizeof(pack));
				break;
			}
			case TYPE_LOGIN:{
				int res  = find_user(pack.name);
				char* msg = NULL;
				if(res == -1){
					msg = "该账号不存在";
				}else{
					user_t user = user_arr[res];// 将找到的用户单独拎出来
					if(strcmp(user.pswd,pack.pswd) == 0){
						msg = "登录成功";
						user_arr[res].sock = client;
						// user_arr[res] 是根据当前登录用户发送过来的账号，找到的存放在数组中的用户结构体
						// client 是当前正在登录的用户在服务器的套接字

						if(user_arr[res].hasMsg == 1){
							// 说明当前用户存在未读消息
							pack_t pack = {0};
							pack.type = TYPE_CHAT;
							strcpy(pack.text , user_arr[res].msg); // 将缓存的消息写入 pack.text 里面
							write(client,&pack,sizeof(pack)); // 将缓存消息发给新登录的客户端
							user_arr[res].hasMsg = 0;
						}
					}else{	
						msg = "密码错误";
					}
				}
				strcpy(pack.text,msg);
				write(client,&pack,sizeof(pack));
				break;
			}
			case TYPE_CHAT:{
				char* msg = NULL;
				// 聊天的时候，客户端会发来如下格式的信息 "张三:你好",表明 你好这条消息是发给张三的
				// 所以我们要根据张三的账号，找到张三的套接字，张三的姓名和套接字都存放在 结构体数组 user_arr里面
				int res = find_user(pack.tarname);
				if(res == -1){
					msg = "该用户不存在";
					strcpy(pack.text,msg);
					write(client,&pack,sizeof(pack));
				}else{
					user_t user = user_arr[res];
					// user_arr[res] 为准备接受聊天信息的用户
					if(user.sock == 0){
						//msg = "用户未登录";
						//strcpy(pack.text,msg);
						//write(client,&pack,sizeof(pack));
						user_arr[res].hasMsg = 1;// 表明当前用户存在了未读消息
						strcpy(user_arr[res].msg , pack.text); // 将准备发送给该用户的消息，缓存到user_arr[res].msg里面去
					}else{
						// 用户存在并登录的状态
						int tarsock = user.sock;
						write(tarsock,&pack,sizeof(pack));
					}
				}
				break;
			}
			case TYPE_FILE_UPLOAD_REQUEST:{
				//printf("接收到客户端文件上传请求:%s %s\n",pack.tarname,pack.filename);
				int res = find_user(pack.tarname);
				if(res == -1){
					// 没注册 
                    printf("该用户不存在\n");
                    break;
				}else{
					if(user_arr[res].sock == 0){
						// 不在线
					}else{
						// 目标用户在线，直接将接收到的pack包转发给目标用户
						printf("转发文件中...\n");
						write(user_arr[res].sock,&pack,sizeof(pack));
					}
				}
			
				
				break;
			}
		}
	//}
}

		

客户端代码：

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <pthread.h>
#include <semaphore.h>
#include <wait.h>
#include <signal.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <semaphore.h>
#include <sys/msg.h>
#include <sys/shm.h>
#include <sys/un.h>

typedef struct sockaddr_in addr_in_t;
typedef struct sockaddr addr_t;
typedef struct sockaddr_un addr_un_t;

enum Type{
	TYPE_REGIST,
	TYPE_LOGIN,
	TYPE_CHAT,
	TYPE_FILE_UPLOAD_REQUEST
};

typedef struct Pack{
	enum Type type;
	char name[20];
	char pswd[20];
	char filename[20];
	long filesize;
	char tarname[20];
	char text[1024];
}pack_t;

void* thread_main(void* arg){
	int client = *(int*)arg;
	while(1){
		pack_t pack = {0};
		int res = read(client,&pack,sizeof(pack));
		if(res == 0){break;}
		switch(pack.type){
    		case TYPE_REGIST:{
				printf("%s\n",pack.text);
       			break;
			}
    		case TYPE_LOGIN:{
				printf("%s\n",pack.text);
       			break;
			}
			case TYPE_CHAT:{
				printf("接收到消息:%s\n",pack.text);
				break;
			}
			case TYPE_FILE_UPLOAD_REQUEST:{
				char filename[128] = "./client_file_system/";
				// 获取文件名，方便打开文件
				strcat(filename , pack.filename);
				int fd = open(filename,O_CREAT | O_TRUNC | O_WRONLY,0666);
				// 获取文件长度
				long filesize = pack.filesize;
				long readed_size = 0;
				
				//printf("接收到文件名和文件大小\n");
				while(1){
					pack_t filepack = {0};
					int res = read(client,&filepack,sizeof(filepack)); // 读取别的客户端发来的文件内容
					if(res != sizeof(filepack)){
						printf("发生分包\n");
					}
					int size = strlen(filepack.text);
				
					//printf("接受到文件信息\n");
					write(fd,filepack.text,size);// 将接受到的文件内容，写入文件中去
					readed_size += size;
					if(readed_size >= filesize){
						close(fd);
						break;
					}

				}
				break;
			}
		}
	}
}

int main(int argc, const char *argv[])
{
	if(argc != 2){
		printf("请输入端口号\n");
		return 1;
	}
	// ./server 8888
	int port = atoi(argv[1]);// 将字符串 8888 转换成int类型port


	int client = socket(AF_INET,SOCK_STREAM,0);
	addr_in_t addr = {0};
	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = inet_addr("192.168.60.77");

	if(connect(client,(addr_t*)&addr,sizeof(addr)) == -1){
		perror("connect");
		return 1;
	}


	pthread_t id;
	pthread_create(&id,0,thread_main,&client);
	pthread_detach(id);

	while(1){
		int ch = -1;
		printf("1:注册\n");
		printf("2:登录\n");
		printf("3:聊天\n");
		printf("4:发送文件\n");
		printf("0:退出\n");
		printf("请选择:");
		scanf("%d",&ch);
		while(getchar()!=10);
		switch(ch){
			case 1:{
				pack_t pack = {0};
				printf("请输入账号:");
				scanf("%s",pack.name);
				while(getchar()!=10);
				printf("请输入密码:");
				scanf("%s",pack.pswd);
				while(getchar()!=10);
				pack.type = TYPE_REGIST;
				write(client,&pack,sizeof(pack));
				break;
			}
			case 2:{
				pack_t pack = {0};
				printf("请输入账号:");
				scanf("%s",pack.name);
				while(getchar()!=10);
				printf("请输入密码:");
				scanf("%s",pack.pswd);
				while(getchar()!=10);
				pack.type = TYPE_LOGIN;
				write(client,&pack,sizeof(pack));
			
				break;
			}
			case 3:{
				// 聊天对象的姓名:聊天内容
				// 聊天对象的姓名放在pack.tarname里面
				// 聊天内容放在 pack.text 里面
				// 张三:你好
				pack_t pack = {0};
				pack.type = TYPE_CHAT;

				scanf("%s %s",pack.tarname,pack.text);
				printf("tarname = %19s\n",pack.tarname);
				while(getchar()!=10);
				write(client,&pack,sizeof(pack));
				break;
			}
			case 4:{
				pack_t pack = {0};
				pack.type = TYPE_FILE_UPLOAD_REQUEST;
				printf("请输入接受文件的用户名:");
				char tarname[20] = "";
				scanf("%19s",pack.tarname);
				strcpy(tarname,pack.tarname);
				while(getchar()!=10);
				printf("请输入想要发送的文件名:");
				scanf("%19s",pack.filename);
				while(getchar()!=10);
				int fd = open(pack.filename,O_RDONLY);
				if(fd == -1){
					printf("该文件不存在\n");
					break;
				}
				struct stat buf = {0};
				stat(pack.filename,&buf);
				pack.filesize = buf.st_size;
				write(client,&pack,sizeof(pack));
				
				while(1){
					pack_t pack = {0};
					pack.type = TYPE_FILE_UPLOAD_REQUEST;
					strcpy(pack.tarname,tarname);
					int res = read(fd,pack.text,1023);
					if(res == 0){break;}
					write(client,&pack,sizeof(pack));
				}
				close(fd);
				break;
			}
			case 0:{
			
				break;
			}
		}
	}
	return 0;
}