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 }
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 }
func cgoLookupIPCNAME(name string) (addrs []IP, cname string, err error, completed bool) { var res *syscall.Addrinfo var hints syscall.Addrinfo hints.Ai_flags = int32(cgoAddrInfoFlags()) hints.Ai_socktype = syscall.SOCK_STREAM h := syscall.StringBytePtr(name) syscall.Entersyscall() gerrno := libc_getaddrinfo(h, nil, &hints, &res) syscall.Exitsyscall() if gerrno != 0 { var str string if gerrno == syscall.EAI_NONAME { str = noSuchHost } else if gerrno == syscall.EAI_SYSTEM { str = syscall.GetErrno().Error() } else { str = bytePtrToString(libc_gai_strerror(gerrno)) } return nil, "", &DNSError{Err: str, Name: name}, true } defer libc_freeaddrinfo(res) if res != nil { cname = bytePtrToString((*byte)(unsafe.Pointer(res.Ai_canonname))) if cname == "" { cname = name } if len(cname) > 0 && cname[len(cname)-1] != '.' { cname += "." } } for r := res; r != nil; r = r.Ai_next { // We only asked for SOCK_STREAM, but check anyhow. if r.Ai_socktype != syscall.SOCK_STREAM { continue } switch r.Ai_family { default: continue case syscall.AF_INET: sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.Ai_addr)) addrs = append(addrs, copyIP(sa.Addr[:])) case syscall.AF_INET6: sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.Ai_addr)) addrs = append(addrs, copyIP(sa.Addr[:])) } } return addrs, cname, nil, true }
func cgoLookupIPCNAME(name string) (addrs []IPAddr, cname string, err error, completed bool) { acquireThread() defer releaseThread() var hints syscall.Addrinfo hints.Ai_flags = int32(cgoAddrInfoFlags) hints.Ai_socktype = syscall.SOCK_STREAM h := syscall.StringBytePtr(name) var res *syscall.Addrinfo syscall.Entersyscall() gerrno := libc_getaddrinfo(h, nil, &hints, &res) syscall.Exitsyscall() if gerrno != 0 { switch gerrno { case syscall.EAI_SYSTEM: errno := syscall.GetErrno() if errno == 0 { // err should not be nil, but sometimes getaddrinfo returns // gerrno == C.EAI_SYSTEM with err == nil on Linux. // The report claims that it happens when we have too many // open files, so use syscall.EMFILE (too many open files in system). // Most system calls would return ENFILE (too many open files), // so at the least EMFILE should be easy to recognize if this // comes up again. golang.org/issue/6232. errno = syscall.EMFILE } err = errno case syscall.EAI_NONAME: err = errNoSuchHost default: err = addrinfoErrno(gerrno) } return nil, "", &DNSError{Err: err.Error(), Name: name}, true } defer libc_freeaddrinfo(res) if res != nil { cname = bytePtrToString((*byte)(unsafe.Pointer(res.Ai_canonname))) if cname == "" { cname = name } if len(cname) > 0 && cname[len(cname)-1] != '.' { cname += "." } } for r := res; r != nil; r = r.Ai_next { // We only asked for SOCK_STREAM, but check anyhow. if r.Ai_socktype != syscall.SOCK_STREAM { continue } switch r.Ai_family { case syscall.AF_INET: sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(r.Ai_addr)) addr := IPAddr{IP: copyIP(sa.Addr[:])} addrs = append(addrs, addr) case syscall.AF_INET6: sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(r.Ai_addr)) addr := IPAddr{IP: copyIP(sa.Addr[:]), Zone: zoneToString(int(sa.Scope_id))} addrs = append(addrs, addr) } } return addrs, cname, nil, true }