当我关闭连接到服务器的客户端时,我从服务器收到此错误,服务器自行关闭。我知道客户端可以优雅地终止连接,但我打算将其发送给某些人,并且不希望我的服务器被关闭只是因为它们没有正常终止。那么什么可以阻止服务器关闭呢? 我正在使用sys / socket.h
这是我的代码的一部分
int server() {
//Set up variables
int sockfd, new_fd; //Listen on sock_fd, new connection on new_fd
struct sockaddr_in my_addr; //My(server) address information
struct sockaddr_in their_addr; //Connector's address information
socklen_t sin_size;
//Generate the socket
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket");
exit(1);
}
//Generate the end point
my_addr.sin_family = AF_INET; //Host byte order
my_addr.sin_port = htons(MYPORT); //Short, network byte order
my_addr.sin_addr.s_addr = INADDR_ANY; //Auto-fill with my IP
if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) \
== -1) {
perror("bind");
exit(1);
}
//Start listnening
if (listen(sockfd, BACKLOG) == -1) {
perror("listen");
exit(1);
}
while(TERMINATE == 0) { // main accept() loop
sin_size = sizeof(struct sockaddr_in);
//Create a new connection for the accepted socket
if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, \
&sin_size)) == -1) {
perror("accept");
continue;
}
//some semaphore stuff
}
return 0;
}
int main(int argc, char *argv[]){
//extra stuff
//Set up mutex locks
pthread_mutex_init(&mutex, NULL);
sem_init(&empty, 0, 30);
sem_init(&full, 0, 0);
//Set up and run Threads
pthread_t threads[30]; //Array of threads
pthread_t server_thread;
pthread_attr_t attr; //Set of thread attributes
//Get the default thread attributes
pthread_attr_init(&attr);
signal(SIGINT, termination);//Wait for a SIGINT
//Loop to create threads and execute consumer_thread
for (int i = 0; i < 30; i++) {
//Set up data in structure
threadArray[i].threadID = i;
threadArray[i].running = 0;
threadArray[i].line_counter_pointer = &line_counter;
threadArray[i].vid_details_pointer = &vid_details;
pthread_create(&threads[i],&attr,consumer_thread, &threadArray[i]);
}
//Execute the producer_thread
pthread_create(&server_thread,&attr,producer_thread, NULL);
//Wait for all the threads to exit
for (int i = 0; i < 30; i++) {
pthread_join(threads[i],NULL);
}
//Destroy semaphores so that it can TERMINATE gracefully
sem_destroy(&empty);
sem_destroy(&full);
return 0;
}
void *producer_thread(void *param) {
server();//Runs the server() function
return NULL;
}
void *consumer_thread(void *param) {
//Pass variable
struct thread_params *threadStruct;
threadStruct = (struct thread_params *) param;
int *line_counter = threadStruct->line_counter_pointer;
vid_details_struct *vid_details = threadStruct->vid_details_pointer;
//End of pass
char found_result [MAXDATASIZE];
int queue_item = 0;
int numbytes;
struct timeval item_wait_time;// Get the current time
while (TERMINATE == 0) { //Main accept() loop
int new_fd;
//Use a variable that would be set to 0 after the client termination
//so that the current connection will be closed on both thread and
//client, that would make thread to go back to idle
int current_connection = 1;
//Acquire full semaphore
sem_wait(&full);
//Acquire mutex lock to protect buffer
pthread_mutex_lock(&mutex);
//some extra stuff including socket information
//now handling queue[queue_item]
new_fd = queue[queue_item].new_fd;
queue[queue_item].waiting = 0;
//Release mutex lock and empty semaphore
pthread_mutex_unlock(&mutex);
sem_post(&empty);
while (current_connection == 1) {
char buf[MAXDATASIZE];
//Receive the query
if ((numbytes=recv(new_fd, buf, MAXDATASIZE, 0)) == -1) {
perror("recv");
exit(1);
}
buf[numbytes] = '\0';//Set the end point of the string
if (!strcmp(buf,"q")) {//Client prompts to TERMINATE
current_connection = 0;//Flag the connection as closed
}
if (current_connection == 1) {//If still connected
//do something
if (send(new_fd, found_result, MAXDATASIZE, 0) == -1) {
perror("send");
close(new_fd);
exit(0);
}
}
}
close(new_fd); // Close the socket connection
//Wait for half a second before accepting a new request
usleep(500000);
}//End of the main while loop
FINISHEDSEMS++;
printf("Thread %d is closing\n", threadStruct->threadID);
return NULL;
}
答案 0 :(得分:2)
这个if语句是您需要查看的内容:
if ((numbytes=recv(new_fd, buf, MAXDATASIZE, 0)) == -1) {
perror("recv");
exit(1);
}
这是您发布的唯一有recv
的地方,所以这就是错误。
查看man page:recv
返回成功完成时消息的长度。如果消息太长而无法容纳在提供的缓冲区中,则可能会丢弃多余的字节,具体取决于接收消息的套接字类型。如果套接字上没有消息可用,则接收调用等待消息到达,除非套接字是非阻塞的(参见fcntl(2)),在这种情况下返回值-1并设置外部变量errno
因此,不要调用exit
(终止进程),而是尝试优雅地处理错误:
if ((numbytes=recv(new_fd, buf, MAXDATASIZE, 0)) < 0) {
// user disconnected or timeout (if you set a timeout)
// NO call to exit; use "continue" or "return", or something else
// to gracefully handle the break;
my_error_function("client disconnected\n");
break;
}
答案 1 :(得分:0)
'由peer重置连接'有许多原因,但最常见的是您已写入已由对等方关闭的连接。换句话说,应用程序协议错误。