C++ 当我关闭客户端套接字时,如何防止服务器关闭?C++;
我有以下代码,即“server.cpp”。它正确地建立与客户端的连接并流式传输视频。问题是,当我关闭客户端时,不管主程序中的while周期如何,服务器也会自动关闭,即使我正在使用pthread_create 您能帮我找到一个解决方案,避免它关闭,并在新客户端连接到它之前保持活动状态吗C++ 当我关闭客户端套接字时,如何防止服务器关闭?C++;,c++,sockets,tcp,server,client,C++,Sockets,Tcp,Server,Client,我有以下代码,即“server.cpp”。它正确地建立与客户端的连接并流式传输视频。问题是,当我关闭客户端时,不管主程序中的while周期如何,服务器也会自动关闭,即使我正在使用pthread_create 您能帮我找到一个解决方案,避免它关闭,并在新客户端连接到它之前保持活动状态吗 /** * OpenCV video streaming over TCP/IP * Server: Captures video from a webcam and send it to a client
/**
* OpenCV video streaming over TCP/IP
* Server: Captures video from a webcam and send it to a client
* by Isaac Maia
*/
#include "opencv2/opencv.hpp"
#include <iostream>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <unistd.h>
#include <string.h>
using namespace cv;
void *display(void *);
int capDev = 0;
VideoCapture cap(capDev); // open the default camera
int main(int argc, char** argv)
{
//--------------------------------------------------------
//networking stuff: socket, bind, listen
//--------------------------------------------------------
int localSocket, remoteSocket, port = 4097;
struct sockaddr_in localAddr, remoteAddr;
pthread_t thread_id;
int addrLen = sizeof(struct sockaddr_in);
if ((argc > 1) && (strcmp(argv[1], "-h") == 0))
{
std::cerr << "usage: ./cv_video_srv [port] [capture device]\n"
<< "port : socket port (4097 default)\n"
<< "capture device : (0 default)\n" << std::endl;
exit(1);
}
if (argc == 2)
port = atoi(argv[1]);
localSocket = socket(AF_INET, SOCK_STREAM, 0);
if (localSocket == -1)
{
perror("socket() call failed!!");
}
localAddr.sin_family = AF_INET;
localAddr.sin_addr.s_addr = INADDR_ANY;
localAddr.sin_port = htons(port);
if (bind(localSocket, (struct sockaddr *) &localAddr, sizeof(localAddr))
< 0)
{
perror("Can't bind() socket");
exit(1);
}
//Listening
listen(localSocket, 3);
std::cout << "Waiting for connections...\n" << "Server Port:" << port
<< std::endl;
//accept connection from an incoming client
while (1)
{
//if (remoteSocket < 0) {
// perror("accept failed!");
// exit(1);
//}
remoteSocket = accept(localSocket,
(struct sockaddr *) &remoteAddr,
(socklen_t*) &addrLen);
//std::cout << remoteSocket<< "32"<< std::endl;
if (remoteSocket < 0)
{
perror("accept failed!");
exit(1);
}
std::cout << "Connection accepted" << std::endl;
pthread_create(&thread_id, NULL, display, &remoteSocket);
//pthread_join(thread_id,NULL);
}
//pthread_join(thread_id,NULL);
//close(remoteSocket);
return 0;
}
void *display(void *ptr)
{
int socket = *(int *) ptr;
//OpenCV Code
//----------------------------------------------------------
Mat img, imgGray;
img = Mat::zeros(480, 640, CV_8UC1);
//make it continuous
if (!img.isContinuous())
{
img = img.clone();
}
int imgSize = img.total() * img.elemSize();
int bytes = 0;
int key;
//make img continuos
if (!img.isContinuous())
{
img = img.clone();
imgGray = img.clone();
}
std::cout << "Image Size:" << imgSize << std::endl;
while (1)
{
/* get a frame from camera */
cap >> img;
//do video processing here
cvtColor(img, imgGray, CV_BGR2GRAY);
//send processed image
if ((bytes = send(socket, imgGray.data, imgSize, 0)) < 0)
{
std::cerr << "bytes = " << bytes << std::endl;
break;
}
}
}
/**
*基于TCP/IP的OpenCV视频流
*服务器:从网络摄像头捕获视频并将其发送到客户端
*艾萨克·玛亚
*/
#包括“opencv2/opencv.hpp”
#包括
#包括
#包括
#包括
#包括
#包括
#包括
使用名称空间cv;
作废*显示(作废*);
int capDev=0;
视频捕获cap(capDev);//打开默认相机
int main(int argc,字符**argv)
{
//--------------------------------------------------------
//网络材料:套接字、绑定、侦听
//--------------------------------------------------------
int localSocket,remoteSocket,端口=4097;
localAddr、remoteAddr中的结构sockaddr\u;
pthread_t thread_id;
int addrLen=sizeof(结构sockaddr_in);
如果((argc>1)和&(strcmp(argv[1],“-h”)==0))
{
std::cerr您没有安全地将remoteSocket
传递到display()
,因此如果另一个客户端在display()之前连接,您的竞争条件可能会改变remoteSocket
的值
有机会使用上一个值。不要传递指向原始remoteSocket
的指针,而是传递它的副本
另外,display()
在退出之前使用接受的套接字时,不会关闭它,因此您正在泄漏套接字描述符。最终,accept()
将由于缺少可用描述符而失败,主循环将退出程序
请尝试类似以下内容:
/**
* OpenCV video streaming over TCP/IP
* Server: Captures video from a webcam and send it to a client
* by Isaac Maia
*/
#include "opencv2/opencv.hpp"
#include <iostream>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <unistd.h>
#include <string.h>
#include <cstdlib>
using namespace cv;
void* display(void *);
int capDev = 0;
VideoCapture cap(capDev); // open the default camera
int main(int argc, char** argv)
{
//--------------------------------------------------------
//networking stuff: socket, bind, listen
//--------------------------------------------------------
int localSocket, remoteSocket;
unsigned short port = 4097;
struct sockaddr_in localAddr, remoteAddr;
socklen_t addrLen;
pthread_t thread_id;
int err;
if (argc > 1)
{
long lport = strtol(argv[1], NULL, 10);
if ((lport <= 0) || (lport > 65535))
{
std::cerr << "usage: ./cv_video_srv [port] [capture device]\n"
<< "port : socket port (4097 default)\n"
<< "capture device : (0 default)\n" << std::endl;
return 1;
}
port = (unsigned short) lport;
}
localSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (localSocket == -1)
{
perror("socket() call failed");
return 1;
}
localAddr.sin_family = AF_INET;
localAddr.sin_addr.s_addr = INADDR_ANY;
localAddr.sin_port = htons(port);
if (bind(localSocket, (struct sockaddr *) &localAddr, sizeof(localAddr)) < 0)
{
perror("Can't bind() socket");
close(localSocket);
return 1;
}
//Listening
if (listen(localSocket, 3) < 0)
{
perror("Can't listen() socket");
close(localSocket);
return 1;
}
std::cout << "Waiting for connections...\n"
<< "Server Port:" << port << std::endl;
//accept connection from an incoming client
while (1)
{
addrLen = sizeof(struct sockaddr_in);
remoteSocket = accept(localSocket,
(struct sockaddr *) &remoteAddr,
&addrLen);
//std::cout << remoteSocket << std::endl;
if (remoteSocket < 0)
{
perror("accept failed");
close(localSocket);
return 1;
}
std::cout << "Connection accepted" << std::endl;
int *socket = new int(remoteSocket);
err = pthread_create(&thread_id, NULL, display, socket);
if (err != 0)
{
//perror("pthread_create failed");
std::cerr << "pthread_create failed: " << strerror(err) << std::endl;
close(remoteSocket);
delete socket;
continue;
}
//pthread_join(thread_id,NULL);
}
//pthread_join(thread_id,NULL);
return 0;
}
void* display(void *ptr)
{
int socket = * (int*) ptr;
delete (int*) ptr;
//OpenCV Code
//----------------------------------------------------------
Mat img, imgGray;
img = Mat::zeros(480, 640, CV_8UC1);
//make it continuous
if (!img.isContinuous())
{
img = img.clone();
}
int imgSize = img.total() * img.elemSize();
int bytes = 0;
int key;
//make img continuos
if (!img.isContinuous())
{
img = img.clone();
imgGray = img.clone();
}
std::cout << "Image Size:" << imgSize << std::endl;
while (1)
{
/* get a frame from camera */
cap >> img;
//do video processing here
cvtColor(img, imgGray, CV_BGR2GRAY);
//send processed image
bytes = send(socket, imgGray.data, imgSize, 0);
if (bytes <= 0)
{
if (bytes < 0)
perror("send failed");
break;
}
}
close(socket);
return NULL;
}
/**
*基于TCP/IP的OpenCV视频流
*服务器:从网络摄像头捕获视频并将其发送到客户端
*艾萨克·玛亚
*/
#包括“opencv2/opencv.hpp”
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
使用名称空间cv;
作废*显示(作废*);
int capDev=0;
VideoCapture cap(capDev);//打开默认摄像机
int main(int argc,字符**argv)
{
//--------------------------------------------------------
//网络材料:套接字、绑定、侦听
//--------------------------------------------------------
int localSocket,remoteSocket;
无符号短端口=4097;
localAddr、remoteAddr中的结构sockaddr\u;
索克伦·阿德伦;
pthread_t thread_id;
INTERR;
如果(argc>1)
{
long lport=strtol(argv[1],NULL,10);
如果((端口65535))
{
std::cerr请正确格式化您的代码,即使用缩进,并告诉我们“退出”的确切含义。它是否崩溃?打印错误并退出?悄悄退出?结束大括号比开始大括号少。循环后,是否显示
执行?使用调试器执行断开逻辑的步骤可能会证明更正确从长远来看,这比问问题更有成效。无关:exit(1)main
中的
是一种毫无意义的return 1;
将执行此任务。如果线程带异常退出,则可能会导致应用程序终止。您应该在try-catch块中运行线程中的所有内容,以防止异常逃逸。(您应该检查pthread的文档。但是线程的任何异常终止都可能导致应用程序终止)。您使用的remoteSocket
存在竞争条件。此解决方案不起作用…我发现,如果在函数显示的调用–发送–中使用标志MSG_NOSIGNAL而不是0,则程序不会关闭…问题是,当我尝试重新连接客户端时,程序将在while(1)之前保持阻塞状态功能上display@F.DEVIVO:请参阅。但是无论使用哪种方法禁用SIGPIPE
,send()
都会在断开连接时失败,并产生错误代码,该代码已处理该错误代码以终止线程循环。除非send()
正在报告成功。当客户端断开连接时,循环应中断。当客户端重新连接时,新线程应启动。