diff options
Diffstat (limited to 'src/pkg/net/dial.go')
| -rw-r--r-- | src/pkg/net/dial.go | 118 |
1 files changed, 65 insertions, 53 deletions
diff --git a/src/pkg/net/dial.go b/src/pkg/net/dial.go index 22e1e7dd8..da5f7e302 100644 --- a/src/pkg/net/dial.go +++ b/src/pkg/net/dial.go @@ -11,7 +11,27 @@ import ( // A DialOption modifies a DialOpt call. type DialOption interface { - dialOption() + setDialOpt(*dialOpts) +} + +var noLocalAddr Addr // nil + +// dialOpts holds all the dial options, populated by a DialOption's +// setDialOpt. +// +// All fields may be their zero value. +type dialOpts struct { + deadline time.Time + localAddr Addr + network string // if empty, "tcp" + deferredConnect bool +} + +func (o *dialOpts) net() string { + if o.network == "" { + return "tcp" + } + return o.network } var ( @@ -38,7 +58,9 @@ func Network(net string) DialOption { type dialNetwork string -func (dialNetwork) dialOption() {} +func (s dialNetwork) setDialOpt(o *dialOpts) { + o.network = string(s) +} // Deadline returns a DialOption to fail a dial that doesn't // complete before t. @@ -46,19 +68,29 @@ func Deadline(t time.Time) DialOption { return dialDeadline(t) } +type dialDeadline time.Time + +func (t dialDeadline) setDialOpt(o *dialOpts) { + o.deadline = time.Time(t) +} + // Timeout returns a DialOption to fail a dial that doesn't // complete within the provided duration. func Timeout(d time.Duration) DialOption { - return dialDeadline(time.Now().Add(d)) + return dialTimeoutOpt(d) } -type dialDeadline time.Time +type dialTimeoutOpt time.Duration -func (dialDeadline) dialOption() {} +func (d dialTimeoutOpt) setDialOpt(o *dialOpts) { + o.deadline = time.Now().Add(time.Duration(d)) +} type tcpFastOpen struct{} -func (tcpFastOpen) dialOption() {} +func (tcpFastOpen) setDialOpt(o *dialOpts) { + o.deferredConnect = true +} // TODO(bradfitz): implement this (golang.org/issue/4842) and unexport this. // @@ -74,7 +106,9 @@ type localAddrOption struct { la Addr } -func (localAddrOption) dialOption() {} +func (a localAddrOption) setDialOpt(o *dialOpts) { + o.localAddr = a.la +} // LocalAddress returns a dial option to perform a dial with the // provided local address. The address must be of a compatible type @@ -135,67 +169,44 @@ func resolveAddr(op, net, addr string, deadline time.Time) (Addr, error) { // "unixpacket". // // For TCP and UDP networks, addresses have the form host:port. -// If host is a literal IPv6 address, it must be enclosed -// in square brackets. The functions JoinHostPort and SplitHostPort -// manipulate addresses in this form. +// If host is a literal IPv6 address or host name, it must be enclosed +// in square brackets as in "[::1]:80", "[ipv6-host]:http" or +// "[ipv6-host%zone]:80". +// The functions JoinHostPort and SplitHostPort manipulate addresses +// in this form. // // Examples: // Dial("tcp", "12.34.56.78:80") -// Dial("tcp", "google.com:80") -// Dial("tcp", "[de:ad:be:ef::ca:fe]:80") +// Dial("tcp", "google.com:http") +// Dial("tcp", "[2001:db8::1]:http") +// Dial("tcp", "[fe80::1%lo0]:80") // -// For IP networks, net must be "ip", "ip4" or "ip6" followed -// by a colon and a protocol number or name. +// For IP networks, the net must be "ip", "ip4" or "ip6" followed by a +// colon and a protocol number or name and the addr must be a literal +// IP address. // // Examples: // Dial("ip4:1", "127.0.0.1") // Dial("ip6:ospf", "::1") // +// For Unix networks, the addr must be a file system path. func Dial(net, addr string) (Conn, error) { return DialOpt(addr, dialNetwork(net)) } -func netFromOptions(opts []DialOption) string { - for _, opt := range opts { - if p, ok := opt.(dialNetwork); ok { - return string(p) - } - } - return "tcp" -} - -func deadlineFromOptions(opts []DialOption) time.Time { - for _, opt := range opts { - if d, ok := opt.(dialDeadline); ok { - return time.Time(d) - } - } - return noDeadline -} - -var noLocalAddr Addr // nil - -func localAddrFromOptions(opts []DialOption) Addr { - for _, opt := range opts { - if o, ok := opt.(localAddrOption); ok { - return o.la - } - } - return noLocalAddr -} - // DialOpt dials addr using the provided options. // If no options are provided, DialOpt(addr) is equivalent // to Dial("tcp", addr). See Dial for the syntax of addr. func DialOpt(addr string, opts ...DialOption) (Conn, error) { - net := netFromOptions(opts) - deadline := deadlineFromOptions(opts) - la := localAddrFromOptions(opts) - ra, err := resolveAddr("dial", net, addr, deadline) + var o dialOpts + for _, opt := range opts { + opt.setDialOpt(&o) + } + ra, err := resolveAddr("dial", o.net(), addr, o.deadline) if err != nil { return nil, err } - return dial(net, addr, la, ra, deadline) + return dial(o.net(), addr, o.localAddr, ra, o.deadline) } func dial(net, addr string, la, ra Addr, deadline time.Time) (c Conn, err error) { @@ -274,7 +285,6 @@ func dialTimeoutRace(net, addr string, timeout time.Duration) (Conn, error) { case p := <-ch: return p.Conn, p.error } - panic("unreachable") } type stringAddr struct { @@ -285,8 +295,9 @@ func (a stringAddr) Network() string { return a.net } func (a stringAddr) String() string { return a.addr } // Listen announces on the local network address laddr. -// The network string net must be a stream-oriented network: -// "tcp", "tcp4", "tcp6", "unix" or "unixpacket". +// The network net must be a stream-oriented network: "tcp", "tcp4", +// "tcp6", "unix" or "unixpacket". +// See Dial for the syntax of laddr. func Listen(net, laddr string) (Listener, error) { la, err := resolveAddr("listen", net, laddr, noDeadline) if err != nil { @@ -302,8 +313,9 @@ func Listen(net, laddr string) (Listener, error) { } // ListenPacket announces on the local network address laddr. -// The network string net must be a packet-oriented network: -// "udp", "udp4", "udp6", "ip", "ip4", "ip6" or "unixgram". +// The network net must be a packet-oriented network: "udp", "udp4", +// "udp6", "ip", "ip4", "ip6" or "unixgram". +// See Dial for the syntax of laddr. func ListenPacket(net, laddr string) (PacketConn, error) { la, err := resolveAddr("listen", net, laddr, noDeadline) if err != nil { |