X-Git-Url: http://git.osdn.net/view?p=bytom%2Fvapor.git;a=blobdiff_plain;f=vendor%2Fgolang.org%2Fx%2Fnet%2Fproxy%2Fproxy.go;fp=vendor%2Fgolang.org%2Fx%2Fnet%2Fproxy%2Fproxy.go;h=553ead7cf0ed03df1b93f2a2894a3eab6cd46ddf;hp=0000000000000000000000000000000000000000;hb=db158dcf09436b003defd333f1a665e7e051d820;hpb=d09b7a78d44dc259725902b8141cdba0d716b121 diff --git a/vendor/golang.org/x/net/proxy/proxy.go b/vendor/golang.org/x/net/proxy/proxy.go new file mode 100644 index 00000000..553ead7c --- /dev/null +++ b/vendor/golang.org/x/net/proxy/proxy.go @@ -0,0 +1,134 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package proxy provides support for a variety of protocols to proxy network +// data. +package proxy // import "golang.org/x/net/proxy" + +import ( + "errors" + "net" + "net/url" + "os" + "sync" +) + +// A Dialer is a means to establish a connection. +type Dialer interface { + // Dial connects to the given address via the proxy. + Dial(network, addr string) (c net.Conn, err error) +} + +// Auth contains authentication parameters that specific Dialers may require. +type Auth struct { + User, Password string +} + +// FromEnvironment returns the dialer specified by the proxy related variables in +// the environment. +func FromEnvironment() Dialer { + allProxy := allProxyEnv.Get() + if len(allProxy) == 0 { + return Direct + } + + proxyURL, err := url.Parse(allProxy) + if err != nil { + return Direct + } + proxy, err := FromURL(proxyURL, Direct) + if err != nil { + return Direct + } + + noProxy := noProxyEnv.Get() + if len(noProxy) == 0 { + return proxy + } + + perHost := NewPerHost(proxy, Direct) + perHost.AddFromString(noProxy) + return perHost +} + +// proxySchemes is a map from URL schemes to a function that creates a Dialer +// from a URL with such a scheme. +var proxySchemes map[string]func(*url.URL, Dialer) (Dialer, error) + +// RegisterDialerType takes a URL scheme and a function to generate Dialers from +// a URL with that scheme and a forwarding Dialer. Registered schemes are used +// by FromURL. +func RegisterDialerType(scheme string, f func(*url.URL, Dialer) (Dialer, error)) { + if proxySchemes == nil { + proxySchemes = make(map[string]func(*url.URL, Dialer) (Dialer, error)) + } + proxySchemes[scheme] = f +} + +// FromURL returns a Dialer given a URL specification and an underlying +// Dialer for it to make network requests. +func FromURL(u *url.URL, forward Dialer) (Dialer, error) { + var auth *Auth + if u.User != nil { + auth = new(Auth) + auth.User = u.User.Username() + if p, ok := u.User.Password(); ok { + auth.Password = p + } + } + + switch u.Scheme { + case "socks5": + return SOCKS5("tcp", u.Host, auth, forward) + } + + // If the scheme doesn't match any of the built-in schemes, see if it + // was registered by another package. + if proxySchemes != nil { + if f, ok := proxySchemes[u.Scheme]; ok { + return f(u, forward) + } + } + + return nil, errors.New("proxy: unknown scheme: " + u.Scheme) +} + +var ( + allProxyEnv = &envOnce{ + names: []string{"ALL_PROXY", "all_proxy"}, + } + noProxyEnv = &envOnce{ + names: []string{"NO_PROXY", "no_proxy"}, + } +) + +// envOnce looks up an environment variable (optionally by multiple +// names) once. It mitigates expensive lookups on some platforms +// (e.g. Windows). +// (Borrowed from net/http/transport.go) +type envOnce struct { + names []string + once sync.Once + val string +} + +func (e *envOnce) Get() string { + e.once.Do(e.init) + return e.val +} + +func (e *envOnce) init() { + for _, n := range e.names { + e.val = os.Getenv(n) + if e.val != "" { + return + } + } +} + +// reset is used by tests +func (e *envOnce) reset() { + e.once = sync.Once{} + e.val = "" +}