Example #1
0
func cgoLookupPort(network, service string) (port int, err error, completed bool) {
	acquireThread()
	defer releaseThread()

	var hints syscall.Addrinfo
	switch network {
	case "": // no hints
	case "tcp", "tcp4", "tcp6":
		hints.Ai_socktype = syscall.SOCK_STREAM
		hints.Ai_protocol = syscall.IPPROTO_TCP
	case "udp", "udp4", "udp6":
		hints.Ai_socktype = syscall.SOCK_DGRAM
		hints.Ai_protocol = syscall.IPPROTO_UDP
	default:
		return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}, true
	}
	if len(network) >= 4 {
		switch network[3] {
		case '4':
			hints.Ai_family = syscall.AF_INET
		case '6':
			hints.Ai_family = syscall.AF_INET6
		}
	}

	s := syscall.StringBytePtr(service)
	var res *syscall.Addrinfo
	syscall.Entersyscall()
	gerrno := libc_getaddrinfo(nil, s, &hints, &res)
	syscall.Exitsyscall()
	if gerrno != 0 {
		switch gerrno {
		case syscall.EAI_SYSTEM:
			errno := syscall.GetErrno()
			if errno == 0 { // see golang.org/issue/6232
				errno = syscall.EMFILE
			}
			err = errno
		default:
			err = addrinfoErrno(gerrno)
		}
		return 0, &DNSError{Err: err.Error(), Name: network + "/" + service}, true
	}
	defer libc_freeaddrinfo(res)

	for r := res; r != nil; r = r.Ai_next {
		switch r.Ai_family {
		case syscall.AF_INET:
			sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.Ai_addr))
			p := (*[2]byte)(unsafe.Pointer(&sa.Port))
			return int(p[0])<<8 | int(p[1]), nil, true
		case syscall.AF_INET6:
			sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.Ai_addr))
			p := (*[2]byte)(unsafe.Pointer(&sa.Port))
			return int(p[0])<<8 | int(p[1]), nil, true
		}
	}
	return 0, &DNSError{Err: "unknown port", Name: network + "/" + service}, true
}
Example #2
0
func cgoLookupPort(net, service string) (port int, err error, completed bool) {
	acquireThread()
	defer releaseThread()

	var res *syscall.Addrinfo
	var hints syscall.Addrinfo

	switch net {
	case "":
		// no hints
	case "tcp", "tcp4", "tcp6":
		hints.Ai_socktype = syscall.SOCK_STREAM
		hints.Ai_protocol = syscall.IPPROTO_TCP
	case "udp", "udp4", "udp6":
		hints.Ai_socktype = syscall.SOCK_DGRAM
		hints.Ai_protocol = syscall.IPPROTO_UDP
	default:
		return 0, UnknownNetworkError(net), true
	}
	if len(net) >= 4 {
		switch net[3] {
		case '4':
			hints.Ai_family = syscall.AF_INET
		case '6':
			hints.Ai_family = syscall.AF_INET6
		}
	}

	s := syscall.StringBytePtr(service)
	syscall.Entersyscall()
	gerrno := libc_getaddrinfo(nil, s, &hints, &res)
	syscall.Exitsyscall()
	if gerrno == 0 {
		defer libc_freeaddrinfo(res)
		for r := res; r != nil; r = r.Ai_next {
			switch r.Ai_family {
			default:
				continue
			case syscall.AF_INET:
				sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.Ai_addr))
				p := (*[2]byte)(unsafe.Pointer(&sa.Port))
				return int(p[0])<<8 | int(p[1]), nil, true
			case syscall.AF_INET6:
				sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.Ai_addr))
				p := (*[2]byte)(unsafe.Pointer(&sa.Port))
				return int(p[0])<<8 | int(p[1]), nil, true
			}
		}
	}
	return 0, &AddrError{"unknown port", net + "/" + service}, true
}