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我一直在使用該網站一段時間（本學期後）期待回饋！但是，我最後一次希望得到你的幫助，而其他答案似乎沒有任何幫助。背景：使用C++，套接字和客戶機/服務器體系結構設計一個基本的聊天室，最多10個客戶機與服務器通話。客戶端所說的任何東西都會在所有客戶端和服務器（除了發送客戶端）之間回顯。使用C++套接字 - 使用accept（）和文件描述符加重錯誤
問題：錯誤發生在recv調用中，作爲clientTalk函數中的while循環條件。我收到了「接收失敗：錯誤的文件描述符」，但服務器和客戶端都沒有「完全崩潰」，並且沒有發生明顯的行爲變化，儘管事實上接收到的是完全轟炸。
試圖解決：
谷歌和SOF。 2小時...
移動變量，帶插座的設置和開放玩弄/關閉
-Valgrind：發生在我的接受聲明
==773== Warning: invalid file descriptor 96600128 in syscall read()
Recieve failed: Bad file descriptor
==773== Thread 2:
==773== Conditional jump or move depends on uninitialised value(s)
==773== at 0x4015A0: ??? (in /nethome/users/ghm455/CS284/ChatServer/server)
==773== by 0x4E39E99: start_thread (pthread_create.c:308)
==773== by 0x5442CBC: clone (clone.S:112)
==773==
==773== Conditional jump or move depends on uninitialised value(s)
==773== at 0x401614: ??? (in /nethome/users/ghm455/CS284/ChatServer/server)
==773== by 0x4E39E99: start_thread (pthread_create.c:308)
==773== by 0x5442CBC: clone (clone.S:112)
==773==
==773== Warning: invalid file descriptor 96600128 in syscall close()
的第一個警告。接收失敗發生在recv上，最後的警告發生在嘗試關閉時。這是由遍佈整個代碼的cout陳述確定的。
CODE：下面。如果您認爲錯誤在那裏，我會發布客戶端，但是一切都指向這是服務器端問題。
`#define SERVER_PORT 9999 /* define a server port number */
using std::cout;
using std::endl;
using std::string;
//Globals - descriptorArray holds client FDs. arraySize is its size.
//soc holds the information on the server's socket.
//m is the global mutex shared among the server and all clients
const int MAX_CLIENT = 10;
int descriptorArray[MAX_CLIENT];
int arraySize = 0;
int soc;
pthread_mutex_t m;
struct thread_info
{
pthread_t threadID; //Stores the ID number returned by pthread_create
int threadNumber; //We have to number incoming threads correctly
char *messageSent; //Message taken in from command line
};
int main()
{
void exitHandler(int sig); // Function that handles the control-C
void* clientTalk(void *arg); // Reads and writes with clients
struct sockaddr_in server_addr, client_addr;
int option = 1;
unsigned int clientCount;
uint8_t *new_socket;
//Initialize the socket
soc = socket(AF_INET, SOCK_STREAM, 0);
if (soc < 0)
{
cout << "ERROR : problem opening socket" <<endl;
return 1;
}
//Create socket structure
bzero((char *) &server_addr, sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = INADDR_ANY;
server_addr.sin_port = htons(SERVER_PORT);
//Binding host address
if (bind(soc, (struct sockaddr *) &server_addr, sizeof(server_addr)) < 0)
{
cout << "ERROR : problem occured while binding" <<endl;
close(soc);
exit(1);
}
if(setsockopt(soc, SOL_SOCKET, SO_REUSEADDR, (char*) &option, sizeof(option)) < 0)
{
printf("setsockopt failed\n");
close(soc);
exit(1);
}
signal(SIGINT, exitHandler);
listen(soc, MAX_CLIENT);
clientCount = sizeof(struct sockaddr_in);
int clientID;
//cout << "Z " <<endl;
while(clientID = accept(soc, (struct sockaddr *) &client_addr, (socklen_t*)&clientCount))
{
//printf("A");
if (clientID < 0)
{
perror("ERROR ON ACCEPT");
exit(1);
}
else
{
pthread_t newClient;
new_socket = (uint8_t*)malloc(1);
*new_socket = clientID;
pthread_mutex_lock(&m);
if (arraySize < 10)
{
descriptorArray[arraySize++] = newClient;
}
else
{
cout << "There are already 10 clients connected!" << endl;
}
pthread_mutex_unlock(&m);
if(pthread_create(&newClient, NULL, clientTalk, &new_socket) < 0)
{
perror("ERROR Creating thread");
return 1;
}
cout << "Assigned!" <<endl;
pthread_join(newClient, NULL);
}
}
close(soc);
return 0;
}
void exitHandler(int sig)
{
sig = sig + 0; //Removing the warning. A clean compile looks a lot nicer.
for (int i = 0; i < arraySize; i++)
{
write(descriptorArray[i], "WARNING: Server exiting in ten seconds. End your conversation!", 1000);
}
cout << "WARNING: Server exiting in ten seconds. ";
cout << "End your conversation!" << endl;
sleep(10f);
for (int i = 0; i < arraySize; i++)
{
close(descriptorArray[i]);
}
close(soc);
exit(1);
}
void* clientTalk(void* arg)
{
int* myFD = (int*) arg;
char buffer[2000];
read(*myFD, buffer, 20);
char username[20];
//strcpy(username, buffer); // Takes in the username and stores it
char movableString[2000];
int amount_read;
// for (int i = 0; i < arraySize; i++)
// {
//strcpy(movableString, username);
// strcat(movableString, " has joined the room!");
//if (descriptorArray[0] != *myFD)
//{
// write(descriptorArray[0], movableString, 2000);
//}
//}
cout << "x" << endl;
int arrayLocation;
while ((amount_read = recv(*myFD, buffer, 2000, MSG_WAITALL)) > 0)
{
cout << " Um" << endl;
pthread_mutex_lock(&m);
for (int i = 0; i < arraySize; i++)
{
if (descriptorArray[i] == *myFD)
{
arrayLocation = i;
break;
}
}
strcpy(movableString, username);
strcat(movableString, ": ");
strcat(movableString, buffer);
for (int i = 0; i < arraySize; i++)
{
//if (i != arrayLocation)
//{
write(*myFD, movableString, 2000);
//}
}
pthread_mutex_unlock(&m);
}
if (amount_read == 0)
{
cout << username << "disconnected unexpectedly" <<endl;
fflush(stdout);
}
if (amount_read == -1)
{
perror("Recieve failed");
}
pthread_mutex_lock(&m);
for (int i = 0; i < arraySize; i++)
{
if (descriptorArray[i] == *myFD)
{
arrayLocation = i;
break;
}
}
for (int i = arrayLocation; i < arraySize - 1; i++)
{
descriptorArray[i] = descriptorArray[i + 1];
}
arraySize--;
pthread_mutex_unlock(&m);
close(*myFD);
pthread_exit(NULL);
free(arg);
}
`
我會監視這個網站回答您的任何問題。我提前道歉，在提出問題時犯任何新手錯誤。
謝謝你的幫助！
當你將套接字傳遞給你的線程時，你使用'int8_t'，它應該是'size_t'（一個指針的大小），而在C++中你應該使用'new'而不是'malloc'。 –
應該是int作爲接受的posix定義返回一個int –
對不起，但我停止閱讀'行爲發生沒有明顯的變化，儘管事實上，接收轟炸完全'這對我來說根本沒有意義 –