517 lines
17 KiB
C
517 lines
17 KiB
C
#include <stdio.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
#include <unistd.h>
|
||
#include <sys/socket.h>
|
||
#include <netinet/in.h>
|
||
#include <arpa/inet.h>
|
||
#include <pthread.h>
|
||
#include <netinet/tcp.h>
|
||
|
||
#define MAX_BUFFER 1024
|
||
#define MAX_USERS 100
|
||
#define MAX_FRIENDS 50
|
||
#define PORT 8888
|
||
|
||
// 用户结构体
|
||
typedef struct {
|
||
char username[50];
|
||
char password[50];
|
||
int friends[MAX_FRIENDS];
|
||
int friend_count;
|
||
int online;
|
||
int socket; // 添加socket字段
|
||
} User;
|
||
|
||
// 全局变量
|
||
User users[MAX_USERS];
|
||
int user_count = 0;
|
||
pthread_mutex_t users_mutex = PTHREAD_MUTEX_INITIALIZER;
|
||
|
||
// 函数声明
|
||
void load_users();
|
||
void save_users();
|
||
int find_user(const char* username);
|
||
void* handle_client(void* arg);
|
||
void process_login(int client_socket, char* buffer);
|
||
void process_register(int client_socket, char* buffer);
|
||
void process_add_friend(int client_socket, char* buffer);
|
||
void process_remove_friend(int client_socket, char* buffer);
|
||
void process_chat(int client_socket, char* buffer);
|
||
void display_online_users(); // 新增函数声明
|
||
void process_get_friends(int client_socket, char* buffer);
|
||
|
||
int main() {
|
||
int server_socket, client_socket;
|
||
struct sockaddr_in server_addr, client_addr;
|
||
socklen_t client_len = sizeof(client_addr);
|
||
pthread_t thread_id;
|
||
|
||
// 加载用户数据
|
||
load_users();
|
||
|
||
// 创建socket
|
||
server_socket = socket(AF_INET, SOCK_STREAM, 0);
|
||
if (server_socket < 0) {
|
||
perror("创建Socket失败");
|
||
exit(EXIT_FAILURE);
|
||
}
|
||
|
||
// 设置服务器地址
|
||
memset(&server_addr, 0, sizeof(server_addr));
|
||
server_addr.sin_family = AF_INET;
|
||
server_addr.sin_addr.s_addr = INADDR_ANY;
|
||
server_addr.sin_port = htons(PORT);
|
||
|
||
// 绑定socket
|
||
if (bind(server_socket, (struct sockaddr*)&server_addr, sizeof(server_addr)) < 0) {
|
||
perror("绑定失败");
|
||
exit(EXIT_FAILURE);
|
||
}
|
||
|
||
// 监听连接
|
||
if (listen(server_socket, 5) < 0) {
|
||
perror("监听失败");
|
||
exit(EXIT_FAILURE);
|
||
}
|
||
|
||
printf("服务器已启动，监听端口 %d\n", PORT);
|
||
|
||
// 接受客户端连接
|
||
while (1) {
|
||
client_socket = accept(server_socket, (struct sockaddr*)&client_addr, &client_len);
|
||
if (client_socket < 0) {
|
||
perror("接受连接失败");
|
||
continue;
|
||
}
|
||
|
||
printf("新客户端连接：%s:%d\n",inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
|
||
|
||
// 为每个客户端创建新线程
|
||
if (pthread_create(&thread_id, NULL, handle_client, (void*)&client_socket) != 0) {
|
||
perror("创建线程失败");
|
||
close(client_socket);
|
||
}
|
||
}
|
||
|
||
close(server_socket);
|
||
return 0;
|
||
}
|
||
|
||
void load_users() {
|
||
FILE* file = fopen("Users.txt", "r");
|
||
if (file == NULL) {
|
||
printf("未找到用户文件，将创建新文件。\n");
|
||
return;
|
||
}
|
||
|
||
while (fscanf(file, "%s %s %d", users[user_count].username,
|
||
users[user_count].password, &users[user_count].friend_count) == 3) {
|
||
for (int i = 0; i < users[user_count].friend_count; i++) {
|
||
fscanf(file, "%d", &users[user_count].friends[i]);
|
||
}
|
||
users[user_count].online = 0;
|
||
users[user_count].socket = -1;
|
||
user_count++;
|
||
}
|
||
|
||
fclose(file);
|
||
}
|
||
|
||
void save_users() {
|
||
FILE* file = fopen("Users.txt", "w");
|
||
if (file == NULL) {
|
||
perror("无法打开用户文件");
|
||
return;
|
||
}
|
||
|
||
for (int i = 0; i < user_count; i++) {
|
||
fprintf(file, "%s %s %d", users[i].username,
|
||
users[i].password, users[i].friend_count);
|
||
for (int j = 0; j < users[i].friend_count; j++) {
|
||
fprintf(file, " %d", users[i].friends[j]);
|
||
}
|
||
fprintf(file, "\n");
|
||
}
|
||
|
||
fclose(file);
|
||
}
|
||
|
||
int find_user(const char* username) {
|
||
for (int i = 0; i < user_count; i++) {
|
||
if (strcmp(users[i].username, username) == 0) {
|
||
return i;
|
||
}
|
||
}
|
||
return -1;
|
||
}
|
||
|
||
void* handle_client(void* arg) {
|
||
int client_socket = *((int*)arg);
|
||
char buffer[MAX_BUFFER];
|
||
int user_index = -1;
|
||
|
||
// 设置socket选项，启用保活机制
|
||
int keepalive = 1;
|
||
int keepidle = 5; // 5秒没有数据交互就开始探测
|
||
int keepinterval = 2; // 探测间隔2秒
|
||
int keepcount = 3; // 探测3次无响应就断开
|
||
|
||
setsockopt(client_socket, SOL_SOCKET, SO_KEEPALIVE, &keepalive, sizeof(keepalive));
|
||
setsockopt(client_socket, IPPROTO_TCP, TCP_KEEPIDLE, &keepidle, sizeof(keepidle));
|
||
setsockopt(client_socket, IPPROTO_TCP, TCP_KEEPINTVL, &keepinterval, sizeof(keepinterval));
|
||
setsockopt(client_socket, IPPROTO_TCP, TCP_KEEPCNT, &keepcount, sizeof(keepcount));
|
||
|
||
while (1) {
|
||
memset(buffer, 0, MAX_BUFFER);
|
||
int bytes_received = recv(client_socket, buffer, MAX_BUFFER, 0);
|
||
|
||
// 检查连接状态
|
||
if (bytes_received <= 0) {
|
||
pthread_mutex_lock(&users_mutex);
|
||
// 查找并更新断开连接的用户状态
|
||
for (int i = 0; i < user_count; i++) {
|
||
if (users[i].socket == client_socket) {
|
||
user_index = i;
|
||
users[i].online = 0;
|
||
users[i].socket = -1;
|
||
printf("\n用户 %s 断开连接\n", users[i].username);
|
||
|
||
// 通知所有在线好友
|
||
for (int j = 0; j < users[i].friend_count; j++) {
|
||
int friend_index = users[i].friends[j];
|
||
if (users[friend_index].online && users[friend_index].socket != -1) {
|
||
char notify[MAX_BUFFER];
|
||
sprintf(notify, "系统消息: 您的好友 %s 已离线", users[i].username);
|
||
send(users[friend_index].socket, notify, MAX_BUFFER, 0);
|
||
}
|
||
}
|
||
break;
|
||
}
|
||
}
|
||
save_users();
|
||
display_online_users();
|
||
pthread_mutex_unlock(&users_mutex);
|
||
break;
|
||
}
|
||
|
||
char command[20];
|
||
sscanf(buffer, "%s", command);
|
||
|
||
if (strcmp(command, "LOGIN") == 0) {
|
||
process_login(client_socket, buffer);
|
||
// 更新user_index
|
||
for (int i = 0; i < user_count; i++) {
|
||
if (users[i].socket == client_socket) {
|
||
user_index = i;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
else if (strcmp(command, "REGISTER") == 0) {
|
||
process_register(client_socket, buffer);
|
||
}
|
||
else if (strcmp(command, "ADDFRIEND") == 0) {
|
||
process_add_friend(client_socket, buffer);
|
||
}
|
||
else if (strcmp(command, "REMOVEFRIEND") == 0) {
|
||
process_remove_friend(client_socket, buffer);
|
||
}
|
||
else if (strcmp(command, "CHAT") == 0) {
|
||
process_chat(client_socket, buffer);
|
||
}
|
||
else if (strcmp(command, "LOGOUT") == 0) {
|
||
pthread_mutex_lock(&users_mutex);
|
||
// 查找当前用户
|
||
for (int i = 0; i < user_count; i++) {
|
||
if (users[i].socket == client_socket) {
|
||
user_index = i;
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (user_index != -1) {
|
||
users[user_index].online = 0;
|
||
users[user_index].socket = -1;
|
||
// 通知所有在线好友
|
||
for (int i = 0; i < users[user_index].friend_count; i++) {
|
||
int friend_index = users[user_index].friends[i];
|
||
if (users[friend_index].online && users[friend_index].socket != -1) {
|
||
char notify[MAX_BUFFER];
|
||
sprintf(notify, "系统消息: 您的好友 %s 已离线", users[user_index].username);
|
||
send(users[friend_index].socket, notify, MAX_BUFFER, 0);
|
||
}
|
||
}
|
||
save_users();
|
||
printf("\n用户 %s 退出登录\n", users[user_index].username);
|
||
display_online_users();
|
||
}
|
||
pthread_mutex_unlock(&users_mutex);
|
||
break;
|
||
}
|
||
else if (strcmp(command, "GETFRIENDS") == 0) {
|
||
process_get_friends(client_socket, buffer);
|
||
}
|
||
}
|
||
|
||
// 确保在断开连接时清理用户状态
|
||
if (user_index != -1) {
|
||
pthread_mutex_lock(&users_mutex);
|
||
users[user_index].online = 0;
|
||
users[user_index].socket = -1;
|
||
save_users();
|
||
display_online_users();
|
||
pthread_mutex_unlock(&users_mutex);
|
||
}
|
||
|
||
close(client_socket);
|
||
return NULL;
|
||
}
|
||
|
||
void process_login(int client_socket, char* buffer) {
|
||
char username[50], password[50];
|
||
sscanf(buffer, "LOGIN %s %s", username, password);
|
||
|
||
pthread_mutex_lock(&users_mutex);
|
||
int user_index = find_user(username);
|
||
|
||
if (user_index == -1) {
|
||
send(client_socket, "FAIL 用户不存在", MAX_BUFFER, 0);
|
||
}
|
||
else if (strcmp(users[user_index].password, password) != 0) {
|
||
send(client_socket, "FAIL 密码错误", MAX_BUFFER, 0);
|
||
}
|
||
else {
|
||
// 如果用户已经在线，先将其标记为离线
|
||
if (users[user_index].online) {
|
||
users[user_index].online = 0;
|
||
users[user_index].socket = -1;
|
||
}
|
||
|
||
// 更新用户状态
|
||
users[user_index].online = 1;
|
||
users[user_index].socket = client_socket;
|
||
save_users();
|
||
|
||
char response[MAX_BUFFER];
|
||
snprintf(response, MAX_BUFFER, "SUCCESS %d", user_index);
|
||
send(client_socket, response, MAX_BUFFER, 0);
|
||
printf("\n用户 %s 登录成功\n", username);
|
||
|
||
// 通知所有在线好友
|
||
for (int i = 0; i < users[user_index].friend_count; i++) {
|
||
int friend_index = users[user_index].friends[i];
|
||
if (users[friend_index].online && users[friend_index].socket != -1) {
|
||
char notify[MAX_BUFFER];
|
||
snprintf(notify, MAX_BUFFER, "系统消息: 您的好友 %s 已上线", username);
|
||
send(users[friend_index].socket, notify, MAX_BUFFER, 0);
|
||
}
|
||
}
|
||
display_online_users();
|
||
}
|
||
pthread_mutex_unlock(&users_mutex);
|
||
}
|
||
|
||
void process_register(int client_socket, char* buffer) {
|
||
char username[50], password[50];
|
||
sscanf(buffer, "REGISTER %s %s", username, password);
|
||
|
||
pthread_mutex_lock(&users_mutex);
|
||
if (find_user(username) != -1) {
|
||
send(client_socket, "FAIL 用户名已存在", MAX_BUFFER, 0);
|
||
}
|
||
else if (user_count >= MAX_USERS) {
|
||
send(client_socket, "FAIL 用户数量已达上限", MAX_BUFFER, 0);
|
||
}
|
||
else {
|
||
strcpy(users[user_count].username, username);
|
||
strcpy(users[user_count].password, password);
|
||
users[user_count].friend_count = 0;
|
||
users[user_count].online = 0;
|
||
users[user_count].socket = -1;
|
||
user_count++;
|
||
save_users();
|
||
send(client_socket, "SUCCESS", MAX_BUFFER, 0);
|
||
}
|
||
pthread_mutex_unlock(&users_mutex);
|
||
}
|
||
|
||
void process_add_friend(int client_socket, char* buffer) {
|
||
int user_index;
|
||
char friend_name[50];
|
||
sscanf(buffer, "ADDFRIEND %d %s", &user_index, friend_name);
|
||
|
||
pthread_mutex_lock(&users_mutex);
|
||
int friend_index = find_user(friend_name);
|
||
|
||
if (friend_index == -1) {
|
||
send(client_socket, "FAIL 好友不存在", MAX_BUFFER, 0);
|
||
}
|
||
else if (user_index == friend_index) {
|
||
send(client_socket, "FAIL 不能添加自己为好友", MAX_BUFFER, 0);
|
||
}
|
||
else {
|
||
// 检查是否已经是好友
|
||
for (int i = 0; i < users[user_index].friend_count; i++) {
|
||
if (users[user_index].friends[i] == friend_index) {
|
||
send(client_socket, "FAIL 已经是好友关系", MAX_BUFFER, 0);
|
||
pthread_mutex_unlock(&users_mutex);
|
||
return;
|
||
}
|
||
}
|
||
|
||
// 添加好友
|
||
users[user_index].friends[users[user_index].friend_count++] = friend_index;
|
||
users[friend_index].friends[users[friend_index].friend_count++] = user_index;
|
||
save_users();
|
||
send(client_socket, "SUCCESS", MAX_BUFFER, 0);
|
||
|
||
// 通知被添加的用户
|
||
if (users[friend_index].online && users[friend_index].socket != -1) {
|
||
char notify[MAX_BUFFER];
|
||
snprintf(notify, MAX_BUFFER, "系统消息: %s 添加您为好友", users[user_index].username);
|
||
send(users[friend_index].socket, notify, MAX_BUFFER, 0);
|
||
}
|
||
}
|
||
pthread_mutex_unlock(&users_mutex);
|
||
}
|
||
|
||
void process_remove_friend(int client_socket, char* buffer) {
|
||
int user_index;
|
||
char friend_name[50];
|
||
sscanf(buffer, "REMOVEFRIEND %d %s", &user_index, friend_name);
|
||
|
||
pthread_mutex_lock(&users_mutex);
|
||
int friend_index = find_user(friend_name);
|
||
|
||
if (friend_index == -1) {
|
||
send(client_socket, "FAIL 好友不存在", MAX_BUFFER, 0);
|
||
pthread_mutex_unlock(&users_mutex);
|
||
return;
|
||
}
|
||
|
||
int found = 0;
|
||
// 从用户的好友列表中移除
|
||
for (int i = 0; i < users[user_index].friend_count; i++) {
|
||
if (users[user_index].friends[i] == friend_index) {
|
||
for (int j = i; j < users[user_index].friend_count - 1; j++) {
|
||
users[user_index].friends[j] = users[user_index].friends[j + 1];
|
||
}
|
||
users[user_index].friend_count--;
|
||
found = 1;
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (found) {
|
||
// 从好友的好友列表中移除
|
||
for (int i = 0; i < users[friend_index].friend_count; i++) {
|
||
if (users[friend_index].friends[i] == user_index) {
|
||
for (int j = i; j < users[friend_index].friend_count - 1; j++) {
|
||
users[friend_index].friends[j] = users[friend_index].friends[j + 1];
|
||
}
|
||
users[friend_index].friend_count--;
|
||
break;
|
||
}
|
||
}
|
||
|
||
save_users();
|
||
|
||
// 发送成功响应
|
||
send(client_socket, "FRIEND_REMOVE_SUCCESS", MAX_BUFFER, 0);
|
||
|
||
// 发送通知给被删除的好友
|
||
if (users[friend_index].online && users[friend_index].socket != -1) {
|
||
char notify[MAX_BUFFER];
|
||
snprintf(notify, MAX_BUFFER, "FRIEND_REMOVE %s 将您从好友列表中移除",
|
||
users[user_index].username);
|
||
send(users[friend_index].socket, notify, MAX_BUFFER, 0);
|
||
}
|
||
} else {
|
||
send(client_socket, "FAIL 不是好友关系", MAX_BUFFER, 0);
|
||
}
|
||
|
||
pthread_mutex_unlock(&users_mutex);
|
||
}
|
||
|
||
void process_chat(int client_socket, char* buffer) {
|
||
int user_index, friend_index;
|
||
char message[MAX_BUFFER];
|
||
sscanf(buffer, "CHAT %d %d %[^\n]", &user_index, &friend_index, message);
|
||
pthread_mutex_lock(&users_mutex);
|
||
// 验证是否是好友关系
|
||
int is_friend = 0;
|
||
for (int i = 0; i < users[user_index].friend_count; i++) {
|
||
if (users[user_index].friends[i] == friend_index) {
|
||
is_friend = 1;
|
||
break;
|
||
}
|
||
}
|
||
|
||
if (!is_friend) {
|
||
send(client_socket, "FAIL 不是好友关系", MAX_BUFFER, 0);
|
||
}
|
||
else {
|
||
char response[MAX_BUFFER];
|
||
// 限制 message 长度，防止溢出
|
||
char safe_message[MAX_BUFFER/2];
|
||
strncpy(safe_message, message, sizeof(safe_message) - 1);
|
||
safe_message[sizeof(safe_message) - 1] = '\0';
|
||
int n = snprintf(response, MAX_BUFFER, "CHAT %s: %s", users[user_index].username, safe_message);
|
||
if (n < 0 || n >= MAX_BUFFER) {
|
||
// 被截断，补上 ...
|
||
strcpy(&response[MAX_BUFFER-5], "...");
|
||
}
|
||
// 发送给发送者
|
||
send(client_socket, response, MAX_BUFFER, 0);
|
||
// 发送给接收者
|
||
if (users[friend_index].online && users[friend_index].socket != -1) {
|
||
send(users[friend_index].socket, response, MAX_BUFFER, 0);
|
||
} else {
|
||
// 好友不在线，给发送者提示
|
||
send(client_socket, "系统消息: 对方不在线，消息未送达", MAX_BUFFER, 0);
|
||
}
|
||
}
|
||
pthread_mutex_unlock(&users_mutex);
|
||
}
|
||
|
||
// 新增函数：显示在线用户
|
||
void display_online_users() {
|
||
printf("\n当前在线用户：\n");
|
||
int online_count = 0;
|
||
for (int i = 0; i < user_count; i++) {
|
||
if (users[i].online) {
|
||
printf("%d. %s\n", ++online_count, users[i].username);
|
||
}
|
||
}
|
||
if (online_count == 0) {
|
||
printf("暂无在线用户\n");
|
||
}
|
||
printf("------------------------\n");
|
||
}
|
||
|
||
// 新增函数：处理获取好友列表请求
|
||
void process_get_friends(int client_socket, char* buffer) {
|
||
int user_index;
|
||
sscanf(buffer, "GETFRIENDS %d", &user_index);
|
||
|
||
pthread_mutex_lock(&users_mutex);
|
||
char response[MAX_BUFFER] = "FRIENDLIST ";
|
||
char temp[64];
|
||
|
||
for (int i = 0; i < users[user_index].friend_count; i++) {
|
||
int friend_index = users[user_index].friends[i];
|
||
int n = snprintf(temp, sizeof(temp), "%s,%d ", users[friend_index].username, friend_index);
|
||
if (n < 0 || n >= sizeof(temp)) {
|
||
strcpy(&temp[sizeof(temp)-5], "...");
|
||
}
|
||
if (strlen(response) + strlen(temp) < MAX_BUFFER) {
|
||
strcat(response, temp);
|
||
} else {
|
||
strcat(response, "...");
|
||
break;
|
||
}
|
||
}
|
||
send(client_socket, response, MAX_BUFFER, 0);
|
||
pthread_mutex_unlock(&users_mutex);
|
||
} |