Function priv_net_create_socket

src/base/net.cpp:825–893

}

static int priv_net_create_socket(int domain, int type, const NETADDR *bindaddr)
{
	int sock = socket(domain, type, 0);
	if(sock < 0)
	{
		log_error("net", "Failed to create socket with domain %d and type %d (%s)", domain, type, net_error_message().c_str());
		return -1;
	}

#if defined(CONF_FAMILY_UNIX)
	// On TCP sockets set SO_REUSEADDR to fix port rebind on restart
	if(domain == AF_INET && type == SOCK_STREAM)
	{
		int reuse_addr = 1;
		if(setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (const char *)&reuse_addr, sizeof(reuse_addr)) != 0)
		{
			log_error("net", "Setting SO_REUSEADDR failed with domain %d and type %d (%s)", domain, type, net_error_message().c_str());
		}
	}
#elif defined(CONF_FAMILY_WINDOWS)
	{
		// Ensure exclusive use of address, otherwise it's possible on Windows to bind to the same address and port with another socket.
		// See https://learn.microsoft.com/en-us/windows/win32/winsock/using-so-reuseaddr-and-so-exclusiveaddruse (last update 06/14/2022)
		int exclusive_addr_use = 1;
		if(setsockopt(sock, SOL_SOCKET, SO_EXCLUSIVEADDRUSE, (const char *)&exclusive_addr_use, sizeof(exclusive_addr_use)) != 0)
		{
			log_error("net", "Setting SO_EXCLUSIVEADDRUSE failed with domain %d and type %d (%s)", domain, type, net_error_message().c_str());
		}
	}
#endif

	// Set to IPv6-only if that's what we are creating, to ensure that dual-stack does not block the same IPv4 port.
#if defined(IPV6_V6ONLY)
	if(domain == AF_INET6)
	{
		int ipv6only = 1;
		if(setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, (const char *)&ipv6only, sizeof(ipv6only)) != 0)
		{
			log_error("net", "Setting IPV6_V6ONLY failed with domain %d and type %d (%s)", domain, type, net_error_message().c_str());
		}
	}
#endif

	sockaddr_storage addr;
	socklen_t addr_len;
	if(bindaddr->type == NETTYPE_IPV4)
	{
		netaddr_to_sockaddr_in(bindaddr, (sockaddr_in *)&addr);
		addr_len = sizeof(sockaddr_in);
	}
	else if(bindaddr->type == NETTYPE_IPV6)
	{
		netaddr_to_sockaddr_in6(bindaddr, (sockaddr_in6 *)&addr);
		addr_len = sizeof(sockaddr_in6);
	}
	else
	{
		dbg_assert_failed("socket type invalid: %d", type);