原则上说,打洞服务器应该是可以返回多个节点的,这里为了简化,只返回一个节点。
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <list>
#include <ostream>
#include <algorithm>
#include "p2pServer.hpp"
namespace ShaCoin
{
static std::list<Node> g_lstNode;
static Node &GetQualityNode(std::list<Node> &lstNode, Node &node)
{
std::list<Node>::iterator it, next;
for (it = lstNode.begin(); it != lstNode.end(); ++it)
{
if (*it == node)
continue;
return *it;
}
return node;
}
}
using namespace ShaCoin;
int main(int argc, char **argv)
{
NodeInfo nodeInfo;
const unsigned long long nodeSize = sizeof(NodeInfo);
memset(&nodeInfo, 0, nodeSize);
char client_ip[16] = { 0 };
int sock = socket(AF_INET, SOCK_DGRAM, 0);
if (sock < 0)
{
perror("socket");
exit(1);
}
int val = 1;
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) < 0)
{
perror("setsockopt");
}
struct sockaddr_in local;
local.sin_family = AF_INET;
local.sin_port = htons(SERVERPORT);
local.sin_addr.s_addr = htonl(INADDR_ANY);
if (bind(sock, (struct sockaddr*)&local, sizeof(local)) < 0)
{
perror("bind");
exit(2);
}
struct sockaddr_in client;
socklen_t len = sizeof(client);
while (1)
{
//读取数据
memset(&nodeInfo, 0, nodeSize);
int r = recvfrom(sock, &nodeInfo, nodeSize, 0, (struct sockaddr*)&client, &len);
if (r < 0)
{
perror("recvfrom");
exit(3);
}
memset(client_ip, 0, sizeof(client_ip));
inet_ntop(AF_INET, &client.sin_addr, client_ip, sizeof(client_ip));
switch (nodeInfo.cmd)
{
case cmd_register:
nodeInfo.node.count = 0;
strcpy(nodeInfo.node.queryIp, client_ip);
nodeInfo.node.queryPort = ntohs(client.sin_port);
printf("query:%s:%d\n", nodeInfo.node.queryIp, nodeInfo.node.queryPort);
printf("recv:%s:%d\n", nodeInfo.node.recvIp, nodeInfo.node.recvPort);
if (g_lstNode.end() == std::find(g_lstNode.begin(), g_lstNode.end(), nodeInfo.node))
g_lstNode.push_back(nodeInfo.node);
if (sendto(sock, &nodeInfo, nodeSize, 0, (struct sockaddr*)&client, len) < 0)
{
perror("sendto");
exit(4);
}
break;
case cmd_unregister:
g_lstNode.remove(nodeInfo.node);
break;
case cmd_getnode:
if (g_lstNode.size() > 1)
{
Node recvNode = nodeInfo.node;
memset(&nodeInfo, 0, nodeSize);
nodeInfo.cmd = cmd_getnode;
nodeInfo.node = GetQualityNode(g_lstNode, recvNode);
++nodeInfo.node.count;
if (sendto(sock, &nodeInfo, nodeSize, 0, (struct sockaddr*)&client, len) < 0)
{
perror("sendto");
exit(4);
}
}
break;
default:
break;
}
}
return 0;
}