C++ 实现的netstat -an 的功能<转>-目的为获取rtmp推流地址如果是域名的话查看1935的ip

目的可能是为了获取rtmp真正的推流ip

如果rtmp推流地址是域名，往CDN推流的话，需要nslookup  的那种DNS解析，然后获取的几个ip

可以使用netstat -n 等命令查看 1935端口的真正ip是多少，废话不多说，下面是代码：

--------------------

 代码中可能只需要关心 EnumTCPTable()  然后判断 if (htons((u_short)pTcpTable->table[i].dwRemotePort) == 1935)

获取该端口的ip

-------------------------------------------------------------------------------------------------------------------------

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <stdio.h>
#include <Iphlpapi.h>
#include <malloc.h>
#include <Winsock2.h>
#include <stdlib.h>
#include <tchar.h>


#pragma comment(lib, "Iphlpapi.lib")
#pragma comment(lib, "ws2_32.lib")


static char TcpState[][32] = 
{
"???",
"CLOSED",
"LISTENING",
"SYN_SENT",
"SEN_RECEIVED",
"ESTABLISHED",
"FIN_WAIT",
"FIN_WAIT2",
"CLOSE_WAIT",
"CLOSING",
"LAST_ACK",
"TIME_WAIT"
};


DWORD EnumTCPTable()
{
PMIB_TCPTABLE pTcpTable = NULL;
DWORD dwSize = 0;
DWORD dwRetVal = ERROR_SUCCESS;

struct   in_addr rip;
struct   in_addr lip;
char  szrip[32] = {0};
char  szlip[32] = {0};

//获得pTcpTable所需要的真实长度,dwSize
if (GetTcpTable(pTcpTable, &dwSize, TRUE) == ERROR_INSUFFICIENT_BUFFER)
{
pTcpTable = (MIB_TCPTABLE*) malloc ((UINT) dwSize);
}
else
return dwRetVal;

printf("Active Connections

");
printf("  Proto	%-24s%-24s%s
","Local Address","Foreign Address","State");

if ((dwRetVal = GetTcpTable(pTcpTable, &dwSize, TRUE)) == NO_ERROR) 
{
for (int i = 0; i < (int) pTcpTable->dwNumEntries; i++) 
{
rip.S_un.S_addr = pTcpTable->table[i].dwRemoteAddr;
lip.S_un.S_addr = pTcpTable->table[i].dwLocalAddr;
//监听端口，远程主机端口为0，但函数返回是有值的，不知道它是怎么考虑的
if (pTcpTable->table[i].dwState == MIB_TCP_STATE_LISTEN)   
pTcpTable->table[i].dwRemotePort = 0;

//dwLocalPort，dwRemotePort 是网络字节
_snprintf(szlip,sizeof(szlip),"%s:%d",inet_ntoa(lip),htons((u_short)pTcpTable->table[i].dwLocalPort));
_snprintf(szrip,sizeof(szrip),"%s:%d",inet_ntoa(rip),htons((u_short)pTcpTable->table[i].dwRemotePort));
printf("  TCP	%-24s%-24s%s
",szlip,szrip,TcpState[pTcpTable->table[i].dwState]);
}
}
else
{
printf("	Call to GetTcpTable failed.
");

LPVOID lpMsgBuf;

if (FormatMessage( 
FORMAT_MESSAGE_ALLOCATE_BUFFER | 
FORMAT_MESSAGE_FROM_SYSTEM | 
FORMAT_MESSAGE_IGNORE_INSERTS,
NULL,
dwRetVal,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
(LPTSTR) &lpMsgBuf,
0,
NULL ))
{
printf("	Error: %s", lpMsgBuf);
}
LocalFree( lpMsgBuf );
}
GlobalFree(pTcpTable);
return dwRetVal;
}


DWORD EnumUDPTable()
{
PMIB_UDPTABLE pUdpTable = NULL;
DWORD dwSize = 0;
DWORD dwRetVal = ERROR_SUCCESS;

// struct   in_addr rip;
struct   in_addr lip;
// char  szrip[32] = {0};
char  szlip[32] = {0};

//获得pUdpTable所需要的真实长度,dwSize
if (GetUdpTable(pUdpTable, &dwSize, TRUE) == ERROR_INSUFFICIENT_BUFFER)
{
pUdpTable = (MIB_UDPTABLE*) malloc ((UINT) dwSize);
}
else
return dwRetVal;

printf("Active Connections

");
printf("  Proto	%-24s%-24s
","Local Addr","Local Port");

if ((dwRetVal = GetUdpTable(pUdpTable, &dwSize, TRUE)) == NO_ERROR) 
{
for (int i = 0; i < (int) pUdpTable->dwNumEntries; i++) 
{
// rip.S_un.S_addr = pUdpTable->table[i].dwRemoteAddr;
lip.S_un.S_addr = pUdpTable->table[i].dwLocalAddr;
//监听端口，远程主机端口为0，但函数返回是有值的，不知道它是怎么考虑的
// if (pUdpTable->table[i].dwState == MIB_Udp_STATE_LISTEN)   
// pUdpTable->table[i].dwRemotePort = 0;

//dwLocalPort，dwRemotePort 是网络字节
_snprintf(szlip,sizeof(szlip),"%s:%d",inet_ntoa(lip),htons((u_short)pUdpTable->table[i].dwLocalPort));
// _snprintf(szrip,sizeof(szrip),"%s:%d",inet_ntoa(rip),htons((u_short)pTcpTable->table[i].dwRemotePort));
// printf("  TCP	%-24s%-24s%s
",szlip,szrip,TcpState[pTcpTable->table[i].dwState]);
printf("  UDP	%-24s
",szlip);
}
}
else
{
printf("	Call to GetUdpTable failed.
");

LPVOID lpMsgBuf;

if (FormatMessage( 
FORMAT_MESSAGE_ALLOCATE_BUFFER | 
FORMAT_MESSAGE_FROM_SYSTEM | 
FORMAT_MESSAGE_IGNORE_INSERTS,
NULL,
dwRetVal,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
(LPTSTR) &lpMsgBuf,
0,
NULL ))
{
printf("	Error: %s", lpMsgBuf);
}
LocalFree( lpMsgBuf );
}
GlobalFree(pUdpTable);
return dwRetVal;
}


DWORD DelTCPConnect(const char *lpszLocalAddr,
const char * lpszRemoteAddr,
DWORD dwLocalPort,
DWORD dwRemotePort)
{
DWORD dwRetVal = ERROR_NOT_FOUND;
MIB_TCPROW srtTcpRow;
srtTcpRow.dwLocalAddr = inet_addr(lpszLocalAddr);
srtTcpRow.dwRemoteAddr = inet_addr(lpszRemoteAddr);
srtTcpRow.dwLocalPort = htons(dwLocalPort);
srtTcpRow.dwRemotePort = htons(dwRemotePort);
srtTcpRow.dwState = MIB_TCP_STATE_DELETE_TCB; //目前为止，settcpEntry只支持该参数
dwRetVal = SetTcpEntry(&srtTcpRow);
if (dwRetVal != ERROR_SUCCESS)
{
LPVOID lpMsgBuf;
if (FormatMessage( 
FORMAT_MESSAGE_ALLOCATE_BUFFER | 
FORMAT_MESSAGE_FROM_SYSTEM | 
FORMAT_MESSAGE_IGNORE_INSERTS,
NULL,
dwRetVal,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
(LPTSTR) &lpMsgBuf,
0,
NULL ))
{
printf("	Error: %s", lpMsgBuf);
}
LocalFree( lpMsgBuf );
}
return dwRetVal;
}


void main()
{
DWORD TcpInfo = EnumTCPTable();
DWORD UdpInfo = EnumUDPTable();
system("pause");
system("pause");
}

http://blog.csdn.net/syytem004/article/details/43272359