Question

我被困在这几个小时，出于某种原因我只在Linux上遇到Segmentation fault错误。它只发生在长度为17或更多字符的数据包中。我正在使用 Enet 库来发送数据包。任何人都可以帮助我，我不知道我在这里缺少什么...

这是gdb输出的屏幕截图这是服务器端示例：

void GameServer::start()
{
if (!m_isRunning)
    m_isRunning = true;

ENetEvent  event;
//ENetPacket *packet;

while (m_isRunning)
{
    while (enet_host_service(server, &event, 1000) > 0)
    {
        switch (event.type)
        {
        case ENET_EVENT_TYPE_CONNECT:
            std::cout << "A new client connected from ";
            std::cout << event.peer->address.host << " ";
            std::cout << event.peer->address.port << std::endl;

            break;
        case ENET_EVENT_TYPE_DISCONNECT:
            printf("%s disconnected.\n", event.peer->data);
            delete (char*)event.peer->data;
            break;
        case ENET_EVENT_TYPE_RECEIVE:
        {
            std::cout << "A packet of length ";
            std::cout << event.packet->dataLength;
            std::cout << " containing ";
            std::cout << event.packet->data;
            std::cout << " was received from ";
            printf("%s", event.peer->data);
            std::cout << " on channel ";
            std::cout << event.channelID << std::endl;

            // Split the packet data, ex:   packettype:data:data
            std::vector<std::string> tokens;
            std::string data;
            std::istringstream split((const char *)event.packet->data);

            // Process the packet data
            while (std::getline(split, data, ':')) Line 89: Crash here
                tokens.push_back(data);

            if (tokens.size() > 1)
            {

                //pc = player connected so we will broadcast the name to all peers
                if (tokens[0] == "pc")
                {
                    if (tokens.size() == 2)
                    {
                        char* data = new char[tokens[1].length() + 1];
                        strcpy(data, tokens[1].c_str());
                        event.peer->data = (void*)data;
                        for (size_t i = 0; i < server->connectedPeers; i++)
                        {
                            enet_host_broadcast(server, 0, event.packet);
                        }
                    }
                }

                //ma = message all so we are going to broadcast the message to all peers
                else if (tokens[0] == "ma") 
                {
                    if (tokens.size() == 2)
                    {
                        enet_host_broadcast(server, 0, event.packet);
                    }
                }


                /* One could just use enet_host_service() instead. */
                enet_host_flush(server);
            }
            /* Clean up the packet now that we're done using it. */
            enet_packet_destroy(event.packet);
            break;
        }
        case ENET_EVENT_TYPE_NONE:
            break;
        default:
            break;
        }

    }
}

}

以下是客户端如何创建数据包，然后将其发送到服务器。

if (connected) {
        std::cout << "Input: ";
        std::string str = "";
        std::getline(std::cin, str);

        if (str.length() == 0) { continue; }

        packet = enet_packet_create(str.c_str(), str.length() + 1, ENET_PACKET_FLAG_RELIABLE);
        enet_peer_send(peer, 0, packet);

    }

如果代码示例不够，我可以提供更多。

Answer 1

malloc()中的崩溃通常意味着有人在某个时间之前写了一个已分配缓冲区的末尾。缓冲区溢出损坏了存储在空闲内存中的指针，以将空闲块链接在一起。在malloc()尝试使用这些指针之前，它没有引起问题。然后是BOOM！

发布event.packet类型的声明。你确定数据[]足够大，可以放入你输入的数据吗？

SIGSEGV，分段错误。仅在Linux上，它适用于Windows

1 个答案: