osci-render/Source/ixwebsocket/IXGetFreePort.cpp

97 wiersze
2.3 KiB
C++

/*
* IXGetFreePort.cpp
* Author: Benjamin Sergeant
* Copyright (c) 2019 Machine Zone. All rights reserved.
*/
// Using inet_addr will trigger an error on uwp without this
// FIXME: use a different api
#ifdef _WIN32
#ifndef _WINSOCK_DEPRECATED_NO_WARNINGS
#define _WINSOCK_DEPRECATED_NO_WARNINGS
#endif
#endif
#include "IXGetFreePort.h"
#include "IXNetSystem.h"
#include "IXSocket.h"
#include <random>
#include <string>
namespace ix
{
int getAnyFreePortRandom()
{
std::random_device rd;
std::uniform_int_distribution<int> dist(1024 + 1, 65535);
return dist(rd);
}
int getAnyFreePort()
{
socket_t sockfd;
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
{
return getAnyFreePortRandom();
}
int enable = 1;
if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (char*) &enable, sizeof(enable)) < 0)
{
return getAnyFreePortRandom();
}
// Bind to port 0. This is the standard way to get a free port.
struct sockaddr_in server; // server address information
server.sin_family = AF_INET;
server.sin_port = htons(0);
server.sin_addr.s_addr = inet_addr("127.0.0.1");
if (bind(sockfd, (struct sockaddr*) &server, sizeof(server)) < 0)
{
Socket::closeSocket(sockfd);
return getAnyFreePortRandom();
}
struct sockaddr_in sa; // server address information
socklen_t len = sizeof(sa);
if (getsockname(sockfd, (struct sockaddr*) &sa, &len) < 0)
{
Socket::closeSocket(sockfd);
return getAnyFreePortRandom();
}
int port = ntohs(sa.sin_port);
Socket::closeSocket(sockfd);
return port;
}
int getFreePort()
{
while (true)
{
#if defined(__has_feature)
#if __has_feature(address_sanitizer)
int port = getAnyFreePortRandom();
#else
int port = getAnyFreePort();
#endif
#else
int port = getAnyFreePort();
#endif
//
// Only port above 1024 can be used by non root users, but for some
// reason I got port 7 returned with macOS when binding on port 0...
//
if (port > 1024)
{
return port;
}
}
return -1;
}
} // namespace ix