Build with "go tool" AND import code from deps

11 files changed, 6933 insertions, 177 deletions

diff --git a/.gitignore b/.gitignore
index 85a298a..75d542a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,5 @@
 /*.bin
+/src/*.a
+/src/*.bin
+/tests/*.a
 /tests/*.bin
diff --git a/Makefile b/Makefile
index a6d47a2..4713192 100644
--- a/Makefile
+++ b/Makefile
@@ -8,6 +8,7 @@ LANGUAGES    = en
 PREFIX       = /usr
 BINDIR       = $(PREFIX)/bin
 LIBDIR       = $(PREFIX)/lib
+GOLIBDIR     = $(LIBDIR)/go
 INCLUDEDIR   = $(PREFIX)/include
 SRCDIR       = $(PREFIX)/src/$(NAME)
 SHAREDIR     = $(PREFIX)/share
@@ -17,12 +18,11 @@ EXEC         = ./
 ## Where to store the installation.  Empty by default.
 DESTDIR      =
 LDLIBS       =
-GOFLAGS      =
 
 
 
 .SUFFIXES:
-.SUFFIXES: .go .bin
+.SUFFIXES: .go .a .bin .bin-check
 
 
 
@@ -30,14 +30,24 @@ all:
 include deps.mk
 
 
+objects = \
+	src/$(NAME).a                  \
+	src/proxy.a                    \
+	src/socks.a                    \
+	src/main.a                     \
+	tests/$(NAME).a                \
+	tests/main.a                   \
+
 sources = \
-	src/lib.go                     \
-	src/cmd/main.go                \
+	src/$(NAME).go                 \
+	src/main.go                    \
 
 
 derived-assets = \
+	$(objects)                     \
+	src/main.bin                   \
+	tests/main.bin                 \
 	$(NAME).bin                    \
-	tests/lib_test.bin             \
 
 side-assets = \
 	$(NAME).socket                 \
@@ -49,22 +59,48 @@ side-assets = \
 all: $(derived-assets)
 
 
-$(NAME).bin: src/lib.go src/cmd/main.go Makefile
-	go build $(GOFLAGS) -v -o $@ src/cmd/main.go
+$(objects): Makefile
+
+src/$(NAME).a: src/$(NAME).go src/proxy.a
+src/proxy.a: src/proxy.go src/socks.a
+src/socks.a: src/socks.go
+src/$(NAME).a src/proxy.a src/socks.a:
+	go tool compile $(GOCFLAGS) -o $@ -p $(*F) -I src $*.go
+
+tests/$(NAME).a: tests/$(NAME).go src/$(NAME).go src/proxy.a
+tests/$(NAME).a:
+	go tool compile $(GOCFLAGS) -o $@ -p $(*F) -I src $*.go src/$(*F).go
+
+src/main.a: src/main.go src/$(NAME).a
+tests/main.a: tests/main.go tests/$(NAME).a
+src/main.a tests/main.a:
+	go tool compile $(GOCFLAGS) -o $@ -I $(@D) $*.go
+
+src/main.bin: src/main.a
+tests/main.bin: tests/main.a
+src/main.bin tests/main.bin:
+	go tool link   $(GOLDFLAGS) -o $@ -L $(@D) -L src $*.a
+
+$(NAME).bin: src/main.bin
+	ln -fs $? $@
+
 
-tests/lib_test.bin: src/lib.go tests/lib_test.go Makefile
-	go test  $(GOFLAGS) -v -o $@ -c $*.go
 
+tests.bin-check = \
+	tests/main.bin-check           \
 
+tests/main.bin-check: tests/main.bin
+$(tests.bin-check):
+	$(EXEC)$*.bin
 
-check-unit: tests/lib_test.bin
-	./tests/lib_test.bin
+check-unit: $(tests.bin-check)
 
 
 integration-tests = \
 	tests/cli-opts.sh              \
 	tests/integration.sh           \
 
+.PRECIOUS: $(integration-tests)
 $(integration-tests): $(NAME).bin
 $(integration-tests): ALWAYS
 	sh $@
@@ -90,21 +126,21 @@ clean:
 install: all
 	mkdir -p \
 		'$(DESTDIR)$(BINDIR)'     \
+		'$(DESTDIR)$(GOLIBDIR)'   \
+		'$(DESTDIR)$(SRCDIR)'     \
 
 	cp $(NAME).bin       '$(DESTDIR)$(BINDIR)'/$(NAME)
-	for f in $(sources); do \
-		dir='$(DESTDIR)$(SRCDIR)'/"`dirname "$${f#src/}"`"; \
-		mkdir -p "$$dir"; \
-		cp -P "$$f" "$$dir"; \
-	done
+	cp src/$(NAME).a     '$(DESTDIR)$(GOLIBDIR)'
+	cp $(sources)        '$(DESTDIR)$(SRCDIR)'
 
 ## Uninstalls from $(DESTDIR)$(PREFIX).  This is a perfect mirror
 ## of the "install" target, and removes *all* that was installed.
 ## A dedicated test asserts that this is always true.
 uninstall:
 	rm -rf \
-		'$(DESTDIR)$(BINDIR)'/$(NAME)       \
-		'$(DESTDIR)$(SRCDIR)'               \
+		'$(DESTDIR)$(BINDIR)'/$(NAME)         \
+		'$(DESTDIR)$(GOLIBDIR)'/$(NAME).a     \
+		'$(DESTDIR)$(SRCDIR)'                 \
 
 
 
diff --git a/go.mod b/go.mod
deleted file mode 100644
index 96e7eeb..0000000
--- a/go.mod
+++ /dev/null
@@ -1,16 +0,0 @@
-module euandre.org/wscat
-
-go 1.21.5
-
-require (
-	euandre.org/gobang v0.1.0
-	github.com/gorilla/websocket v1.5.3
-)
-
-require golang.org/x/net v0.26.0 // indirect
-
-replace (
-	euandre.org/gobang => ../gobang
-	github.com/gorilla/websocket => ../websocket
-	golang.org/x/net => ../netx
-)
diff --git a/src/lib.go b/src/lib.go
deleted file mode 100644
index 3733475..0000000
--- a/src/lib.go
+++ /dev/null
@@ -1,118 +0,0 @@
-package wscat
-
-import (
-	"fmt"
-	"net"
-	"net/http"
-	"os"
-
-	g "euandre.org/gobang/src"
-
-	"github.com/gorilla/websocket"
-)
-
-
-
-type CLIArgs struct {
-	FromAddr string
-	ToAddr   string
-}
-
-
-
-const X = 1
-
-var EmitActiveConnection = g.MakeGauge("active-connections")
-
-
-
-func ParseArgs(args []string) CLIArgs {
-	if len(args) != 3 {
-		fmt.Fprintf(
-			os.Stderr,
-			"Usage: %s FROM.socket TO.socket\n",
-			args[0],
-		)
-		os.Exit(2)
-	}
-	return CLIArgs {
-		FromAddr: args[1],
-		ToAddr:   args[2],
-	}
-}
-
-func Listen(fromAddr string) net.Listener {
-	listener, err := net.Listen("unix", fromAddr)
-	g.FatalIf(err)
-	g.Info("Started listening", "listen-start", "from-address", fromAddr)
-	return listener
-}
-
-func Start(toAddr string, listener net.Listener) {
-	upgrader := websocket.Upgrader {}
-	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
-		connFrom, err := upgrader.Upgrade(w, r, nil)
-		if err != nil {
-			g.Warning(
-				"Error upgrading connection",
-				"upgrade-connection-error",
-				"err", err,
-			)
-			return
-		}
-		defer connFrom.Close()
-		EmitActiveConnection.Inc()
-
-		connTo, err := net.Dial("unix", toAddr)
-		if err != nil {
-			g.Error(
-				"Error dialing connection",
-				"dial-connection",
-				"err", err,
-			)
-			os.Exit(1)
-		}
-		defer connTo.Close()
-
-		messageType, reader, err := connFrom.NextReader()
-		if err != nil {
-			g.Warning(
-				"Failed to get next reader from connection",
-				"connection-next-reader-error",
-				"err", err,
-			)
-			return
-		}
-
-		writer, err := connFrom.NextWriter(messageType)
-		if err != nil {
-			g.Warning(
-				"Failed to get next reader from connection",
-				"connection-next-reader-error",
-				"err", err,
-			)
-			return
-		}
-
-
-		c := make(chan g.CopyResult)
-		go g.CopyData(c, "c2s", connTo, writer)
-		go g.CopyData(c, "s2c", reader, connTo)
-		go func() {
-			<- c
-			EmitActiveConnection.Dec()
-		}()
-	});
-
-	server := http.Server{}
-	err := server.Serve(listener)
-	g.FatalIf(err)
-}
-
-
-func Main() {
-	g.Init()
-	args := ParseArgs(os.Args)
-	listener := Listen(args.FromAddr)
-	Start(args.ToAddr, listener)
-}
diff --git a/src/cmd/main.go b/src/main.go
index e6ae309..ddc8f19 100644
--- a/src/cmd/main.go
+++ b/src/main.go
@@ -1,6 +1,6 @@
 package main
 
-import "euandre.org/wscat/src"
+import "wscat"
 
 func main() {
 	wscat.Main()
diff --git a/src/proxy.go b/src/proxy.go
new file mode 100644
index 0000000..7ef4be3
--- /dev/null
+++ b/src/proxy.go
@@ -0,0 +1,405 @@
+// Copyright 2019 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
+
+import (
+	"context"
+	"errors"
+	"net"
+	"net/url"
+	"os"
+	"strings"
+	"sync"
+
+	"socks"
+)
+
+// A ContextDialer dials using a context.
+type ContextDialer interface {
+	DialContext(ctx context.Context, network, address string) (net.Conn, error)
+}
+
+// Dial works like DialContext on net.Dialer but using a dialer returned by FromEnvironment.
+//
+// The passed ctx is only used for returning the Conn, not the lifetime of the Conn.
+//
+// Custom dialers (registered via RegisterDialerType) that do not implement ContextDialer
+// can leak a goroutine for as long as it takes the underlying Dialer implementation to timeout.
+//
+// A Conn returned from a successful Dial after the context has been cancelled will be immediately closed.
+func Dial(ctx context.Context, network, address string) (net.Conn, error) {
+	d := FromEnvironment()
+	if xd, ok := d.(ContextDialer); ok {
+		return xd.DialContext(ctx, network, address)
+	}
+	return dialContext(ctx, d, network, address)
+}
+
+// WARNING: this can leak a goroutine for as long as the underlying Dialer implementation takes to timeout
+// A Conn returned from a successful Dial after the context has been cancelled will be immediately closed.
+func dialContext(ctx context.Context, d Dialer, network, address string) (net.Conn, error) {
+	var (
+		conn net.Conn
+		done = make(chan struct{}, 1)
+		err  error
+	)
+	go func() {
+		conn, err = d.Dial(network, address)
+		close(done)
+		if conn != nil && ctx.Err() != nil {
+			conn.Close()
+		}
+	}()
+	select {
+	case <-ctx.Done():
+		err = ctx.Err()
+	case <-done:
+	}
+	return conn, err
+}
+// 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.
+
+
+type direct struct{}
+
+// Direct implements Dialer by making network connections directly using net.Dial or net.DialContext.
+var Direct = direct{}
+
+var (
+	_ Dialer        = Direct
+	_ ContextDialer = Direct
+)
+
+// Dial directly invokes net.Dial with the supplied parameters.
+func (direct) Dial(network, addr string) (net.Conn, error) {
+	return net.Dial(network, addr)
+}
+
+// DialContext instantiates a net.Dialer and invokes its DialContext receiver with the supplied parameters.
+func (direct) DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
+	var d net.Dialer
+	return d.DialContext(ctx, network, addr)
+}
+// 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.
+
+
+// A PerHost directs connections to a default Dialer unless the host name
+// requested matches one of a number of exceptions.
+type PerHost struct {
+	def, bypass Dialer
+
+	bypassNetworks []*net.IPNet
+	bypassIPs      []net.IP
+	bypassZones    []string
+	bypassHosts    []string
+}
+
+// NewPerHost returns a PerHost Dialer that directs connections to either
+// defaultDialer or bypass, depending on whether the connection matches one of
+// the configured rules.
+func NewPerHost(defaultDialer, bypass Dialer) *PerHost {
+	return &PerHost{
+		def:    defaultDialer,
+		bypass: bypass,
+	}
+}
+
+// Dial connects to the address addr on the given network through either
+// defaultDialer or bypass.
+func (p *PerHost) Dial(network, addr string) (c net.Conn, err error) {
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+
+	return p.dialerForRequest(host).Dial(network, addr)
+}
+
+// DialContext connects to the address addr on the given network through either
+// defaultDialer or bypass.
+func (p *PerHost) DialContext(ctx context.Context, network, addr string) (c net.Conn, err error) {
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+	d := p.dialerForRequest(host)
+	if x, ok := d.(ContextDialer); ok {
+		return x.DialContext(ctx, network, addr)
+	}
+	return dialContext(ctx, d, network, addr)
+}
+
+func (p *PerHost) dialerForRequest(host string) Dialer {
+	if ip := net.ParseIP(host); ip != nil {
+		for _, net := range p.bypassNetworks {
+			if net.Contains(ip) {
+				return p.bypass
+			}
+		}
+		for _, bypassIP := range p.bypassIPs {
+			if bypassIP.Equal(ip) {
+				return p.bypass
+			}
+		}
+		return p.def
+	}
+
+	for _, zone := range p.bypassZones {
+		if strings.HasSuffix(host, zone) {
+			return p.bypass
+		}
+		if host == zone[1:] {
+			// For a zone ".example.com", we match "example.com"
+			// too.
+			return p.bypass
+		}
+	}
+	for _, bypassHost := range p.bypassHosts {
+		if bypassHost == host {
+			return p.bypass
+		}
+	}
+	return p.def
+}
+
+// AddFromString parses a string that contains comma-separated values
+// specifying hosts that should use the bypass proxy. Each value is either an
+// IP address, a CIDR range, a zone (*.example.com) or a host name
+// (localhost). A best effort is made to parse the string and errors are
+// ignored.
+func (p *PerHost) AddFromString(s string) {
+	hosts := strings.Split(s, ",")
+	for _, host := range hosts {
+		host = strings.TrimSpace(host)
+		if len(host) == 0 {
+			continue
+		}
+		if strings.Contains(host, "/") {
+			// We assume that it's a CIDR address like 127.0.0.0/8
+			if _, net, err := net.ParseCIDR(host); err == nil {
+				p.AddNetwork(net)
+			}
+			continue
+		}
+		if ip := net.ParseIP(host); ip != nil {
+			p.AddIP(ip)
+			continue
+		}
+		if strings.HasPrefix(host, "*.") {
+			p.AddZone(host[1:])
+			continue
+		}
+		p.AddHost(host)
+	}
+}
+
+// AddIP specifies an IP address that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match an IP.
+func (p *PerHost) AddIP(ip net.IP) {
+	p.bypassIPs = append(p.bypassIPs, ip)
+}
+
+// AddNetwork specifies an IP range that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match.
+func (p *PerHost) AddNetwork(net *net.IPNet) {
+	p.bypassNetworks = append(p.bypassNetworks, net)
+}
+
+// AddZone specifies a DNS suffix that will use the bypass proxy. A zone of
+// "example.com" matches "example.com" and all of its subdomains.
+func (p *PerHost) AddZone(zone string) {
+	zone = strings.TrimSuffix(zone, ".")
+	if !strings.HasPrefix(zone, ".") {
+		zone = "." + zone
+	}
+	p.bypassZones = append(p.bypassZones, zone)
+}
+
+// AddHost specifies a host name that will use the bypass proxy.
+func (p *PerHost) AddHost(host string) {
+	host = strings.TrimSuffix(host, ".")
+	p.bypassHosts = append(p.bypassHosts, host)
+}
+// 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"
+
+// A Dialer is a means to establish a connection.
+// Custom dialers should also implement ContextDialer.
+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 and makes underlying connections
+// directly.
+func FromEnvironment() Dialer {
+	return FromEnvironmentUsing(Direct)
+}
+
+// FromEnvironmentUsing returns the dialer specify by the proxy-related
+// variables in the environment and makes underlying connections
+// using the provided forwarding Dialer (for instance, a *net.Dialer
+// with desired configuration).
+func FromEnvironmentUsing(forward Dialer) Dialer {
+	allProxy := allProxyEnv.Get()
+	if len(allProxy) == 0 {
+		return forward
+	}
+
+	proxyURL, err := url.Parse(allProxy)
+	if err != nil {
+		return forward
+	}
+	proxy, err := FromURL(proxyURL, forward)
+	if err != nil {
+		return forward
+	}
+
+	noProxy := noProxyEnv.Get()
+	if len(noProxy) == 0 {
+		return proxy
+	}
+
+	perHost := NewPerHost(proxy, forward)
+	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", "socks5h":
+		addr := u.Hostname()
+		port := u.Port()
+		if port == "" {
+			port = "1080"
+		}
+		return SOCKS5("tcp", net.JoinHostPort(addr, port), 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 = ""
+}
+// 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.
+
+
+// SOCKS5 returns a Dialer that makes SOCKSv5 connections to the given
+// address with an optional username and password.
+// See RFC 1928 and RFC 1929.
+func SOCKS5(network, address string, auth *Auth, forward Dialer) (Dialer, error) {
+	d := socks.NewDialer(network, address)
+	if forward != nil {
+		if f, ok := forward.(ContextDialer); ok {
+			d.ProxyDial = func(ctx context.Context, network string, address string) (net.Conn, error) {
+				return f.DialContext(ctx, network, address)
+			}
+		} else {
+			d.ProxyDial = func(ctx context.Context, network string, address string) (net.Conn, error) {
+				return dialContext(ctx, forward, network, address)
+			}
+		}
+	}
+	if auth != nil {
+		up := socks.UsernamePassword{
+			Username: auth.User,
+			Password: auth.Password,
+		}
+		d.AuthMethods = []socks.AuthMethod{
+			socks.AuthMethodNotRequired,
+			socks.AuthMethodUsernamePassword,
+		}
+		d.Authenticate = up.Authenticate
+	}
+	return d, nil
+}
diff --git a/src/socks.go b/src/socks.go
new file mode 100644
index 0000000..d506505
--- /dev/null
+++ b/src/socks.go
@@ -0,0 +1,473 @@
+// Package socks provides a SOCKS version 5 client implementation.
+//
+// SOCKS protocol version 5 is defined in RFC 1928.
+// Username/Password authentication for SOCKS version 5 is defined in
+// RFC 1929.
+package socks
+
+import (
+	"context"
+	"errors"
+	"io"
+	"net"
+	"strconv"
+	"time"
+)
+
+
+
+var (
+	noDeadline   = time.Time{}
+	aLongTimeAgo = time.Unix(1, 0)
+)
+
+func (d *Dialer) connect(ctx context.Context, c net.Conn, address string) (_ net.Addr, ctxErr error) {
+	host, port, err := splitHostPort(address)
+	if err != nil {
+		return nil, err
+	}
+	if deadline, ok := ctx.Deadline(); ok && !deadline.IsZero() {
+		c.SetDeadline(deadline)
+		defer c.SetDeadline(noDeadline)
+	}
+	if ctx != context.Background() {
+		errCh := make(chan error, 1)
+		done := make(chan struct{})
+		defer func() {
+			close(done)
+			if ctxErr == nil {
+				ctxErr = <-errCh
+			}
+		}()
+		go func() {
+			select {
+			case <-ctx.Done():
+				c.SetDeadline(aLongTimeAgo)
+				errCh <- ctx.Err()
+			case <-done:
+				errCh <- nil
+			}
+		}()
+	}
+
+	b := make([]byte, 0, 6+len(host)) // the size here is just an estimate
+	b = append(b, Version5)
+	if len(d.AuthMethods) == 0 || d.Authenticate == nil {
+		b = append(b, 1, byte(AuthMethodNotRequired))
+	} else {
+		ams := d.AuthMethods
+		if len(ams) > 255 {
+			return nil, errors.New("too many authentication methods")
+		}
+		b = append(b, byte(len(ams)))
+		for _, am := range ams {
+			b = append(b, byte(am))
+		}
+	}
+	if _, ctxErr = c.Write(b); ctxErr != nil {
+		return
+	}
+
+	if _, ctxErr = io.ReadFull(c, b[:2]); ctxErr != nil {
+		return
+	}
+	if b[0] != Version5 {
+		return nil, errors.New("unexpected protocol version " + strconv.Itoa(int(b[0])))
+	}
+	am := AuthMethod(b[1])
+	if am == AuthMethodNoAcceptableMethods {
+		return nil, errors.New("no acceptable authentication methods")
+	}
+	if d.Authenticate != nil {
+		if ctxErr = d.Authenticate(ctx, c, am); ctxErr != nil {
+			return
+		}
+	}
+
+	b = b[:0]
+	b = append(b, Version5, byte(d.cmd), 0)
+	if ip := net.ParseIP(host); ip != nil {
+		if ip4 := ip.To4(); ip4 != nil {
+			b = append(b, AddrTypeIPv4)
+			b = append(b, ip4...)
+		} else if ip6 := ip.To16(); ip6 != nil {
+			b = append(b, AddrTypeIPv6)
+			b = append(b, ip6...)
+		} else {
+			return nil, errors.New("unknown address type")
+		}
+	} else {
+		if len(host) > 255 {
+			return nil, errors.New("FQDN too long")
+		}
+		b = append(b, AddrTypeFQDN)
+		b = append(b, byte(len(host)))
+		b = append(b, host...)
+	}
+	b = append(b, byte(port>>8), byte(port))
+	if _, ctxErr = c.Write(b); ctxErr != nil {
+		return
+	}
+
+	if _, ctxErr = io.ReadFull(c, b[:4]); ctxErr != nil {
+		return
+	}
+	if b[0] != Version5 {
+		return nil, errors.New("unexpected protocol version " + strconv.Itoa(int(b[0])))
+	}
+	if cmdErr := Reply(b[1]); cmdErr != StatusSucceeded {
+		return nil, errors.New("unknown error " + cmdErr.String())
+	}
+	if b[2] != 0 {
+		return nil, errors.New("non-zero reserved field")
+	}
+	l := 2
+	var a Addr
+	switch b[3] {
+	case AddrTypeIPv4:
+		l += net.IPv4len
+		a.IP = make(net.IP, net.IPv4len)
+	case AddrTypeIPv6:
+		l += net.IPv6len
+		a.IP = make(net.IP, net.IPv6len)
+	case AddrTypeFQDN:
+		if _, err := io.ReadFull(c, b[:1]); err != nil {
+			return nil, err
+		}
+		l += int(b[0])
+	default:
+		return nil, errors.New("unknown address type " + strconv.Itoa(int(b[3])))
+	}
+	if cap(b) < l {
+		b = make([]byte, l)
+	} else {
+		b = b[:l]
+	}
+	if _, ctxErr = io.ReadFull(c, b); ctxErr != nil {
+		return
+	}
+	if a.IP != nil {
+		copy(a.IP, b)
+	} else {
+		a.Name = string(b[:len(b)-2])
+	}
+	a.Port = int(b[len(b)-2])<<8 | int(b[len(b)-1])
+	return &a, nil
+}
+
+func splitHostPort(address string) (string, int, error) {
+	host, port, err := net.SplitHostPort(address)
+	if err != nil {
+		return "", 0, err
+	}
+	portnum, err := strconv.Atoi(port)
+	if err != nil {
+		return "", 0, err
+	}
+	if 1 > portnum || portnum > 0xffff {
+		return "", 0, errors.New("port number out of range " + port)
+	}
+	return host, portnum, nil
+}
+// Copyright 2018 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.
+
+// A Command represents a SOCKS command.
+type Command int
+
+func (cmd Command) String() string {
+	switch cmd {
+	case CmdConnect:
+		return "socks connect"
+	case cmdBind:
+		return "socks bind"
+	default:
+		return "socks " + strconv.Itoa(int(cmd))
+	}
+}
+
+// An AuthMethod represents a SOCKS authentication method.
+type AuthMethod int
+
+// A Reply represents a SOCKS command reply code.
+type Reply int
+
+func (code Reply) String() string {
+	switch code {
+	case StatusSucceeded:
+		return "succeeded"
+	case 0x01:
+		return "general SOCKS server failure"
+	case 0x02:
+		return "connection not allowed by ruleset"
+	case 0x03:
+		return "network unreachable"
+	case 0x04:
+		return "host unreachable"
+	case 0x05:
+		return "connection refused"
+	case 0x06:
+		return "TTL expired"
+	case 0x07:
+		return "command not supported"
+	case 0x08:
+		return "address type not supported"
+	default:
+		return "unknown code: " + strconv.Itoa(int(code))
+	}
+}
+
+// Wire protocol constants.
+const (
+	Version5 = 0x05
+
+	AddrTypeIPv4 = 0x01
+	AddrTypeFQDN = 0x03
+	AddrTypeIPv6 = 0x04
+
+	CmdConnect Command = 0x01 // establishes an active-open forward proxy connection
+	cmdBind    Command = 0x02 // establishes a passive-open forward proxy connection
+
+	AuthMethodNotRequired         AuthMethod = 0x00 // no authentication required
+	AuthMethodUsernamePassword    AuthMethod = 0x02 // use username/password
+	AuthMethodNoAcceptableMethods AuthMethod = 0xff // no acceptable authentication methods
+
+	StatusSucceeded Reply = 0x00
+)
+
+// An Addr represents a SOCKS-specific address.
+// Either Name or IP is used exclusively.
+type Addr struct {
+	Name string // fully-qualified domain name
+	IP   net.IP
+	Port int
+}
+
+func (a *Addr) Network() string { return "socks" }
+
+func (a *Addr) String() string {
+	if a == nil {
+		return "<nil>"
+	}
+	port := strconv.Itoa(a.Port)
+	if a.IP == nil {
+		return net.JoinHostPort(a.Name, port)
+	}
+	return net.JoinHostPort(a.IP.String(), port)
+}
+
+// A Conn represents a forward proxy connection.
+type Conn struct {
+	net.Conn
+
+	boundAddr net.Addr
+}
+
+// BoundAddr returns the address assigned by the proxy server for
+// connecting to the command target address from the proxy server.
+func (c *Conn) BoundAddr() net.Addr {
+	if c == nil {
+		return nil
+	}
+	return c.boundAddr
+}
+
+// A Dialer holds SOCKS-specific options.
+type Dialer struct {
+	cmd          Command // either CmdConnect or cmdBind
+	proxyNetwork string  // network between a proxy server and a client
+	proxyAddress string  // proxy server address
+
+	// ProxyDial specifies the optional dial function for
+	// establishing the transport connection.
+	ProxyDial func(context.Context, string, string) (net.Conn, error)
+
+	// AuthMethods specifies the list of request authentication
+	// methods.
+	// If empty, SOCKS client requests only AuthMethodNotRequired.
+	AuthMethods []AuthMethod
+
+	// Authenticate specifies the optional authentication
+	// function. It must be non-nil when AuthMethods is not empty.
+	// It must return an error when the authentication is failed.
+	Authenticate func(context.Context, io.ReadWriter, AuthMethod) error
+}
+
+// DialContext connects to the provided address on the provided
+// network.
+//
+// The returned error value may be a net.OpError. When the Op field of
+// net.OpError contains "socks", the Source field contains a proxy
+// server address and the Addr field contains a command target
+// address.
+//
+// See func Dial of the net package of standard library for a
+// description of the network and address parameters.
+func (d *Dialer) DialContext(ctx context.Context, network, address string) (net.Conn, error) {
+	if err := d.validateTarget(network, address); err != nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: err}
+	}
+	if ctx == nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: errors.New("nil context")}
+	}
+	var err error
+	var c net.Conn
+	if d.ProxyDial != nil {
+		c, err = d.ProxyDial(ctx, d.proxyNetwork, d.proxyAddress)
+	} else {
+		var dd net.Dialer
+		c, err = dd.DialContext(ctx, d.proxyNetwork, d.proxyAddress)
+	}
+	if err != nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: err}
+	}
+	a, err := d.connect(ctx, c, address)
+	if err != nil {
+		c.Close()
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: err}
+	}
+	return &Conn{Conn: c, boundAddr: a}, nil
+}
+
+// DialWithConn initiates a connection from SOCKS server to the target
+// network and address using the connection c that is already
+// connected to the SOCKS server.
+//
+// It returns the connection's local address assigned by the SOCKS
+// server.
+func (d *Dialer) DialWithConn(ctx context.Context, c net.Conn, network, address string) (net.Addr, error) {
+	if err := d.validateTarget(network, address); err != nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: err}
+	}
+	if ctx == nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: errors.New("nil context")}
+	}
+	a, err := d.connect(ctx, c, address)
+	if err != nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: err}
+	}
+	return a, nil
+}
+
+// Dial connects to the provided address on the provided network.
+//
+// Unlike DialContext, it returns a raw transport connection instead
+// of a forward proxy connection.
+//
+// Deprecated: Use DialContext or DialWithConn instead.
+func (d *Dialer) Dial(network, address string) (net.Conn, error) {
+	if err := d.validateTarget(network, address); err != nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: err}
+	}
+	var err error
+	var c net.Conn
+	if d.ProxyDial != nil {
+		c, err = d.ProxyDial(context.Background(), d.proxyNetwork, d.proxyAddress)
+	} else {
+		c, err = net.Dial(d.proxyNetwork, d.proxyAddress)
+	}
+	if err != nil {
+		proxy, dst, _ := d.pathAddrs(address)
+		return nil, &net.OpError{Op: d.cmd.String(), Net: network, Source: proxy, Addr: dst, Err: err}
+	}
+	if _, err := d.DialWithConn(context.Background(), c, network, address); err != nil {
+		c.Close()
+		return nil, err
+	}
+	return c, nil
+}
+
+func (d *Dialer) validateTarget(network, address string) error {
+	switch network {
+	case "tcp", "tcp6", "tcp4":
+	default:
+		return errors.New("network not implemented")
+	}
+	switch d.cmd {
+	case CmdConnect, cmdBind:
+	default:
+		return errors.New("command not implemented")
+	}
+	return nil
+}
+
+func (d *Dialer) pathAddrs(address string) (proxy, dst net.Addr, err error) {
+	for i, s := range []string{d.proxyAddress, address} {
+		host, port, err := splitHostPort(s)
+		if err != nil {
+			return nil, nil, err
+		}
+		a := &Addr{Port: port}
+		a.IP = net.ParseIP(host)
+		if a.IP == nil {
+			a.Name = host
+		}
+		if i == 0 {
+			proxy = a
+		} else {
+			dst = a
+		}
+	}
+	return
+}
+
+// NewDialer returns a new Dialer that dials through the provided
+// proxy server's network and address.
+func NewDialer(network, address string) *Dialer {
+	return &Dialer{proxyNetwork: network, proxyAddress: address, cmd: CmdConnect}
+}
+
+const (
+	authUsernamePasswordVersion = 0x01
+	authStatusSucceeded         = 0x00
+)
+
+// UsernamePassword are the credentials for the username/password
+// authentication method.
+type UsernamePassword struct {
+	Username string
+	Password string
+}
+
+// Authenticate authenticates a pair of username and password with the
+// proxy server.
+func (up *UsernamePassword) Authenticate(ctx context.Context, rw io.ReadWriter, auth AuthMethod) error {
+	switch auth {
+	case AuthMethodNotRequired:
+		return nil
+	case AuthMethodUsernamePassword:
+		if len(up.Username) == 0 || len(up.Username) > 255 || len(up.Password) > 255 {
+			return errors.New("invalid username/password")
+		}
+		b := []byte{authUsernamePasswordVersion}
+		b = append(b, byte(len(up.Username)))
+		b = append(b, up.Username...)
+		b = append(b, byte(len(up.Password)))
+		b = append(b, up.Password...)
+		// TODO(mikio): handle IO deadlines and cancelation if
+		// necessary
+		if _, err := rw.Write(b); err != nil {
+			return err
+		}
+		if _, err := io.ReadFull(rw, b[:2]); err != nil {
+			return err
+		}
+		if b[0] != authUsernamePasswordVersion {
+			return errors.New("invalid username/password version")
+		}
+		if b[1] != authStatusSucceeded {
+			return errors.New("username/password authentication failed")
+		}
+		return nil
+	}
+	return errors.New("unsupported authentication method " + strconv.Itoa(int(auth)))
+}
diff --git a/src/wscat.go b/src/wscat.go
new file mode 100644
index 0000000..b9a17a6
--- /dev/null
+++ b/src/wscat.go
@@ -0,0 +1,3148 @@
+package wscat
+
+import (
+	"bufio"
+	"bytes"
+	"compress/flate"
+	"context"
+	"crypto/rand"
+	"crypto/sha1"
+	"crypto/tls"
+	"encoding/base64"
+	"encoding/binary"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/http/httptrace"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+	"unicode/utf8"
+	"unsafe"
+
+	"proxy"
+
+	g "gobang"
+)
+
+// ErrBadHandshake is returned when the server response to opening handshake is
+// invalid.
+var ErrBadHandshake = errors.New("websocket: bad handshake")
+
+var errInvalidCompression = errors.New("websocket: invalid compression negotiation")
+
+// NewClient creates a new client connection using the given net connection.
+// The URL u specifies the host and request URI. Use requestHeader to specify
+// the origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies
+// (Cookie). Use the response.Header to get the selected subprotocol
+// (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
+//
+// If the WebSocket handshake fails, ErrBadHandshake is returned along with a
+// non-nil *http.Response so that callers can handle redirects, authentication,
+// etc.
+//
+// Deprecated: Use Dialer instead.
+func NewClient(netConn net.Conn, u *url.URL, requestHeader http.Header, readBufSize, writeBufSize int) (c *Conn, response *http.Response, err error) {
+	d := Dialer{
+		ReadBufferSize:  readBufSize,
+		WriteBufferSize: writeBufSize,
+		NetDial: func(net, addr string) (net.Conn, error) {
+			return netConn, nil
+		},
+	}
+	return d.Dial(u.String(), requestHeader)
+}
+
+// A Dialer contains options for connecting to WebSocket server.
+//
+// It is safe to call Dialer's methods concurrently.
+type Dialer struct {
+	// NetDial specifies the dial function for creating TCP connections. If
+	// NetDial is nil, net.Dialer DialContext is used.
+	NetDial func(network, addr string) (net.Conn, error)
+
+	// NetDialContext specifies the dial function for creating TCP connections. If
+	// NetDialContext is nil, NetDial is used.
+	NetDialContext func(ctx context.Context, network, addr string) (net.Conn, error)
+
+	// NetDialTLSContext specifies the dial function for creating TLS/TCP connections. If
+	// NetDialTLSContext is nil, NetDialContext is used.
+	// If NetDialTLSContext is set, Dial assumes the TLS handshake is done there and
+	// TLSClientConfig is ignored.
+	NetDialTLSContext func(ctx context.Context, network, addr string) (net.Conn, error)
+
+	// Proxy specifies a function to return a proxy for a given
+	// Request. If the function returns a non-nil error, the
+	// request is aborted with the provided error.
+	// If Proxy is nil or returns a nil *URL, no proxy is used.
+	Proxy func(*http.Request) (*url.URL, error)
+
+	// TLSClientConfig specifies the TLS configuration to use with tls.Client.
+	// If nil, the default configuration is used.
+	// If either NetDialTLS or NetDialTLSContext are set, Dial assumes the TLS handshake
+	// is done there and TLSClientConfig is ignored.
+	TLSClientConfig *tls.Config
+
+	// HandshakeTimeout specifies the duration for the handshake to complete.
+	HandshakeTimeout time.Duration
+
+	// ReadBufferSize and WriteBufferSize specify I/O buffer sizes in bytes. If a buffer
+	// size is zero, then a useful default size is used. The I/O buffer sizes
+	// do not limit the size of the messages that can be sent or received.
+	ReadBufferSize, WriteBufferSize int
+
+	// WriteBufferPool is a pool of buffers for write operations. If the value
+	// is not set, then write buffers are allocated to the connection for the
+	// lifetime of the connection.
+	//
+	// A pool is most useful when the application has a modest volume of writes
+	// across a large number of connections.
+	//
+	// Applications should use a single pool for each unique value of
+	// WriteBufferSize.
+	WriteBufferPool BufferPool
+
+	// Subprotocols specifies the client's requested subprotocols.
+	Subprotocols []string
+
+	// EnableCompression specifies if the client should attempt to negotiate
+	// per message compression (RFC 7692). Setting this value to true does not
+	// guarantee that compression will be supported. Currently only "no context
+	// takeover" modes are supported.
+	EnableCompression bool
+
+	// Jar specifies the cookie jar.
+	// If Jar is nil, cookies are not sent in requests and ignored
+	// in responses.
+	Jar http.CookieJar
+}
+
+// Dial creates a new client connection by calling DialContext with a background context.
+func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
+	return d.DialContext(context.Background(), urlStr, requestHeader)
+}
+
+var errMalformedURL = errors.New("malformed ws or wss URL")
+
+func hostPortNoPort(u *url.URL) (hostPort, hostNoPort string) {
+	hostPort = u.Host
+	hostNoPort = u.Host
+	if i := strings.LastIndex(u.Host, ":"); i > strings.LastIndex(u.Host, "]") {
+		hostNoPort = hostNoPort[:i]
+	} else {
+		switch u.Scheme {
+		case "wss":
+			hostPort += ":443"
+		case "https":
+			hostPort += ":443"
+		default:
+			hostPort += ":80"
+		}
+	}
+	return hostPort, hostNoPort
+}
+
+// DefaultDialer is a dialer with all fields set to the default values.
+var DefaultDialer = &Dialer{
+	Proxy:            http.ProxyFromEnvironment,
+	HandshakeTimeout: 45 * time.Second,
+}
+
+// nilDialer is dialer to use when receiver is nil.
+var nilDialer = *DefaultDialer
+
+// DialContext creates a new client connection. Use requestHeader to specify the
+// origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies (Cookie).
+// Use the response.Header to get the selected subprotocol
+// (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
+//
+// The context will be used in the request and in the Dialer.
+//
+// If the WebSocket handshake fails, ErrBadHandshake is returned along with a
+// non-nil *http.Response so that callers can handle redirects, authentication,
+// etcetera. The response body may not contain the entire response and does not
+// need to be closed by the application.
+func (d *Dialer) DialContext(ctx context.Context, urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
+	if d == nil {
+		d = &nilDialer
+	}
+
+	challengeKey, err := generateChallengeKey()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	u, err := url.Parse(urlStr)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	switch u.Scheme {
+	case "ws":
+		u.Scheme = "http"
+	case "wss":
+		u.Scheme = "https"
+	default:
+		return nil, nil, errMalformedURL
+	}
+
+	if u.User != nil {
+		// User name and password are not allowed in websocket URIs.
+		return nil, nil, errMalformedURL
+	}
+
+	req := &http.Request{
+		Method:     http.MethodGet,
+		URL:        u,
+		Proto:      "HTTP/1.1",
+		ProtoMajor: 1,
+		ProtoMinor: 1,
+		Header:     make(http.Header),
+		Host:       u.Host,
+	}
+	req = req.WithContext(ctx)
+
+	// Set the cookies present in the cookie jar of the dialer
+	if d.Jar != nil {
+		for _, cookie := range d.Jar.Cookies(u) {
+			req.AddCookie(cookie)
+		}
+	}
+
+	// Set the request headers using the capitalization for names and values in
+	// RFC examples. Although the capitalization shouldn't matter, there are
+	// servers that depend on it. The Header.Set method is not used because the
+	// method canonicalizes the header names.
+	req.Header["Upgrade"] = []string{"websocket"}
+	req.Header["Connection"] = []string{"Upgrade"}
+	req.Header["Sec-WebSocket-Key"] = []string{challengeKey}
+	req.Header["Sec-WebSocket-Version"] = []string{"13"}
+	if len(d.Subprotocols) > 0 {
+		req.Header["Sec-WebSocket-Protocol"] = []string{strings.Join(d.Subprotocols, ", ")}
+	}
+	for k, vs := range requestHeader {
+		switch {
+		case k == "Host":
+			if len(vs) > 0 {
+				req.Host = vs[0]
+			}
+		case k == "Upgrade" ||
+			k == "Connection" ||
+			k == "Sec-Websocket-Key" ||
+			k == "Sec-Websocket-Version" ||
+			k == "Sec-Websocket-Extensions" ||
+			(k == "Sec-Websocket-Protocol" && len(d.Subprotocols) > 0):
+			return nil, nil, errors.New("websocket: duplicate header not allowed: " + k)
+		case k == "Sec-Websocket-Protocol":
+			req.Header["Sec-WebSocket-Protocol"] = vs
+		default:
+			req.Header[k] = vs
+		}
+	}
+
+	if d.EnableCompression {
+		req.Header["Sec-WebSocket-Extensions"] = []string{"permessage-deflate; server_no_context_takeover; client_no_context_takeover"}
+	}
+
+	if d.HandshakeTimeout != 0 {
+		var cancel func()
+		ctx, cancel = context.WithTimeout(ctx, d.HandshakeTimeout)
+		defer cancel()
+	}
+
+	var netDial netDialerFunc
+	switch {
+	case u.Scheme == "https" && d.NetDialTLSContext != nil:
+		netDial = d.NetDialTLSContext
+	case d.NetDialContext != nil:
+		netDial = d.NetDialContext
+	case d.NetDial != nil:
+		netDial = func(ctx context.Context, net, addr string) (net.Conn, error) {
+			return d.NetDial(net, addr)
+		}
+	default:
+		netDial = (&net.Dialer{}).DialContext
+	}
+
+	// If needed, wrap the dial function to set the connection deadline.
+	if deadline, ok := ctx.Deadline(); ok {
+		forwardDial := netDial
+		netDial = func(ctx context.Context, network, addr string) (net.Conn, error) {
+			c, err := forwardDial(ctx, network, addr)
+			if err != nil {
+				return nil, err
+			}
+			err = c.SetDeadline(deadline)
+			if err != nil {
+				c.Close()
+				return nil, err
+			}
+			return c, nil
+		}
+	}
+
+	// If needed, wrap the dial function to connect through a proxy.
+	if d.Proxy != nil {
+		proxyURL, err := d.Proxy(req)
+		if err != nil {
+			return nil, nil, err
+		}
+		if proxyURL != nil {
+			netDial, err = proxyFromURL(proxyURL, netDial)
+			if err != nil {
+				return nil, nil, err
+			}
+		}
+	}
+
+	hostPort, hostNoPort := hostPortNoPort(u)
+	trace := httptrace.ContextClientTrace(ctx)
+	if trace != nil && trace.GetConn != nil {
+		trace.GetConn(hostPort)
+	}
+
+	netConn, err := netDial(ctx, "tcp", hostPort)
+	if err != nil {
+		return nil, nil, err
+	}
+	if trace != nil && trace.GotConn != nil {
+		trace.GotConn(httptrace.GotConnInfo{
+			Conn: netConn,
+		})
+	}
+
+	// Close the network connection when returning an error. The variable
+	// netConn is set to nil before the success return at the end of the
+	// function.
+	defer func() {
+		if netConn != nil {
+			// It's safe to ignore the error from Close() because this code is
+			// only executed when returning a more important error to the
+			// application.
+			_ = netConn.Close()
+		}
+	}()
+
+	if u.Scheme == "https" && d.NetDialTLSContext == nil {
+		// If NetDialTLSContext is set, assume that the TLS handshake has already been done
+
+		cfg := cloneTLSConfig(d.TLSClientConfig)
+		if cfg.ServerName == "" {
+			cfg.ServerName = hostNoPort
+		}
+		tlsConn := tls.Client(netConn, cfg)
+		netConn = tlsConn
+
+		if trace != nil && trace.TLSHandshakeStart != nil {
+			trace.TLSHandshakeStart()
+		}
+		err := doHandshake(ctx, tlsConn, cfg)
+		if trace != nil && trace.TLSHandshakeDone != nil {
+			trace.TLSHandshakeDone(tlsConn.ConnectionState(), err)
+		}
+
+		if err != nil {
+			return nil, nil, err
+		}
+	}
+
+	conn := newConn(netConn, false, d.ReadBufferSize, d.WriteBufferSize, d.WriteBufferPool, nil, nil)
+
+	if err := req.Write(netConn); err != nil {
+		return nil, nil, err
+	}
+
+	if trace != nil && trace.GotFirstResponseByte != nil {
+		if peek, err := conn.br.Peek(1); err == nil && len(peek) == 1 {
+			trace.GotFirstResponseByte()
+		}
+	}
+
+	resp, err := http.ReadResponse(conn.br, req)
+	if err != nil {
+		if d.TLSClientConfig != nil {
+			for _, proto := range d.TLSClientConfig.NextProtos {
+				if proto != "http/1.1" {
+					return nil, nil, fmt.Errorf(
+						"websocket: protocol %q was given but is not supported;"+
+							"sharing tls.Config with net/http Transport can cause this error: %w",
+						proto, err,
+					)
+				}
+			}
+		}
+		return nil, nil, err
+	}
+
+	if d.Jar != nil {
+		if rc := resp.Cookies(); len(rc) > 0 {
+			d.Jar.SetCookies(u, rc)
+		}
+	}
+
+	if resp.StatusCode != 101 ||
+		!tokenListContainsValue(resp.Header, "Upgrade", "websocket") ||
+		!tokenListContainsValue(resp.Header, "Connection", "upgrade") ||
+		resp.Header.Get("Sec-Websocket-Accept") != computeAcceptKey(challengeKey) {
+		// Before closing the network connection on return from this
+		// function, slurp up some of the response to aid application
+		// debugging.
+		buf := make([]byte, 1024)
+		n, _ := io.ReadFull(resp.Body, buf)
+		resp.Body = io.NopCloser(bytes.NewReader(buf[:n]))
+		return nil, resp, ErrBadHandshake
+	}
+
+	for _, ext := range parseExtensions(resp.Header) {
+		if ext[""] != "permessage-deflate" {
+			continue
+		}
+		_, snct := ext["server_no_context_takeover"]
+		_, cnct := ext["client_no_context_takeover"]
+		if !snct || !cnct {
+			return nil, resp, errInvalidCompression
+		}
+		conn.newCompressionWriter = compressNoContextTakeover
+		conn.newDecompressionReader = decompressNoContextTakeover
+		break
+	}
+
+	resp.Body = io.NopCloser(bytes.NewReader([]byte{}))
+	conn.subprotocol = resp.Header.Get("Sec-Websocket-Protocol")
+
+	if err := netConn.SetDeadline(time.Time{}); err != nil {
+		return nil, resp, err
+	}
+
+	// Success! Set netConn to nil to stop the deferred function above from
+	// closing the network connection.
+	netConn = nil
+
+	return conn, resp, nil
+}
+
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+	return cfg.Clone()
+}
+
+func doHandshake(ctx context.Context, tlsConn *tls.Conn, cfg *tls.Config) error {
+	if err := tlsConn.HandshakeContext(ctx); err != nil {
+		return err
+	}
+	if !cfg.InsecureSkipVerify {
+		if err := tlsConn.VerifyHostname(cfg.ServerName); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+const (
+	minCompressionLevel     = -2 // flate.HuffmanOnly not defined in Go < 1.6
+	maxCompressionLevel     = flate.BestCompression
+	defaultCompressionLevel = 1
+)
+
+var (
+	flateWriterPools [maxCompressionLevel - minCompressionLevel + 1]sync.Pool
+	flateReaderPool  = sync.Pool{New: func() interface{} {
+		return flate.NewReader(nil)
+	}}
+)
+
+func decompressNoContextTakeover(r io.Reader) io.ReadCloser {
+	const tail =
+	// Add four bytes as specified in RFC
+	"\x00\x00\xff\xff" +
+		// Add final block to squelch unexpected EOF error from flate reader.
+		"\x01\x00\x00\xff\xff"
+
+	fr, _ := flateReaderPool.Get().(io.ReadCloser)
+	mr := io.MultiReader(r, strings.NewReader(tail))
+	if err := fr.(flate.Resetter).Reset(mr, nil); err != nil {
+		// Reset never fails, but handle error in case that changes.
+		fr = flate.NewReader(mr)
+	}
+	return &flateReadWrapper{fr}
+}
+
+func isValidCompressionLevel(level int) bool {
+	return minCompressionLevel <= level && level <= maxCompressionLevel
+}
+
+func compressNoContextTakeover(w io.WriteCloser, level int) io.WriteCloser {
+	p := &flateWriterPools[level-minCompressionLevel]
+	tw := &truncWriter{w: w}
+	fw, _ := p.Get().(*flate.Writer)
+	if fw == nil {
+		fw, _ = flate.NewWriter(tw, level)
+	} else {
+		fw.Reset(tw)
+	}
+	return &flateWriteWrapper{fw: fw, tw: tw, p: p}
+}
+
+// truncWriter is an io.Writer that writes all but the last four bytes of the
+// stream to another io.Writer.
+type truncWriter struct {
+	w io.WriteCloser
+	n int
+	p [4]byte
+}
+
+func (w *truncWriter) Write(p []byte) (int, error) {
+	n := 0
+
+	// fill buffer first for simplicity.
+	if w.n < len(w.p) {
+		n = copy(w.p[w.n:], p)
+		p = p[n:]
+		w.n += n
+		if len(p) == 0 {
+			return n, nil
+		}
+	}
+
+	m := len(p)
+	if m > len(w.p) {
+		m = len(w.p)
+	}
+
+	if nn, err := w.w.Write(w.p[:m]); err != nil {
+		return n + nn, err
+	}
+
+	copy(w.p[:], w.p[m:])
+	copy(w.p[len(w.p)-m:], p[len(p)-m:])
+	nn, err := w.w.Write(p[:len(p)-m])
+	return n + nn, err
+}
+
+type flateWriteWrapper struct {
+	fw *flate.Writer
+	tw *truncWriter
+	p  *sync.Pool
+}
+
+func (w *flateWriteWrapper) Write(p []byte) (int, error) {
+	if w.fw == nil {
+		return 0, errWriteClosed
+	}
+	return w.fw.Write(p)
+}
+
+func (w *flateWriteWrapper) Close() error {
+	if w.fw == nil {
+		return errWriteClosed
+	}
+	err1 := w.fw.Flush()
+	w.p.Put(w.fw)
+	w.fw = nil
+	if w.tw.p != [4]byte{0, 0, 0xff, 0xff} {
+		return errors.New("websocket: internal error, unexpected bytes at end of flate stream")
+	}
+	err2 := w.tw.w.Close()
+	if err1 != nil {
+		return err1
+	}
+	return err2
+}
+
+type flateReadWrapper struct {
+	fr io.ReadCloser
+}
+
+func (r *flateReadWrapper) Read(p []byte) (int, error) {
+	if r.fr == nil {
+		return 0, io.ErrClosedPipe
+	}
+	n, err := r.fr.Read(p)
+	if err == io.EOF {
+		// Preemptively place the reader back in the pool. This helps with
+		// scenarios where the application does not call NextReader() soon after
+		// this final read.
+		r.Close()
+	}
+	return n, err
+}
+
+func (r *flateReadWrapper) Close() error {
+	if r.fr == nil {
+		return io.ErrClosedPipe
+	}
+	err := r.fr.Close()
+	flateReaderPool.Put(r.fr)
+	r.fr = nil
+	return err
+}
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+const (
+	// Frame header byte 0 bits from Section 5.2 of RFC 6455
+	finalBit = 1 << 7
+	rsv1Bit  = 1 << 6
+	rsv2Bit  = 1 << 5
+	rsv3Bit  = 1 << 4
+
+	// Frame header byte 1 bits from Section 5.2 of RFC 6455
+	maskBit = 1 << 7
+
+	maxFrameHeaderSize         = 2 + 8 + 4 // Fixed header + length + mask
+	maxControlFramePayloadSize = 125
+
+	writeWait = time.Second
+
+	defaultReadBufferSize  = 4096
+	defaultWriteBufferSize = 4096
+
+	continuationFrame = 0
+	noFrame           = -1
+)
+
+// Close codes defined in RFC 6455, section 11.7.
+const (
+	CloseNormalClosure           = 1000
+	CloseGoingAway               = 1001
+	CloseProtocolError           = 1002
+	CloseUnsupportedData         = 1003
+	CloseNoStatusReceived        = 1005
+	CloseAbnormalClosure         = 1006
+	CloseInvalidFramePayloadData = 1007
+	ClosePolicyViolation         = 1008
+	CloseMessageTooBig           = 1009
+	CloseMandatoryExtension      = 1010
+	CloseInternalServerErr       = 1011
+	CloseServiceRestart          = 1012
+	CloseTryAgainLater           = 1013
+	CloseTLSHandshake            = 1015
+)
+
+// The message types are defined in RFC 6455, section 11.8.
+const (
+	// TextMessage denotes a text data message. The text message payload is
+	// interpreted as UTF-8 encoded text data.
+	TextMessage = 1
+
+	// BinaryMessage denotes a binary data message.
+	BinaryMessage = 2
+
+	// CloseMessage denotes a close control message. The optional message
+	// payload contains a numeric code and text. Use the FormatCloseMessage
+	// function to format a close message payload.
+	CloseMessage = 8
+
+	// PingMessage denotes a ping control message. The optional message payload
+	// is UTF-8 encoded text.
+	PingMessage = 9
+
+	// PongMessage denotes a pong control message. The optional message payload
+	// is UTF-8 encoded text.
+	PongMessage = 10
+)
+
+// ErrCloseSent is returned when the application writes a message to the
+// connection after sending a close message.
+var ErrCloseSent = errors.New("websocket: close sent")
+
+// ErrReadLimit is returned when reading a message that is larger than the
+// read limit set for the connection.
+var ErrReadLimit = errors.New("websocket: read limit exceeded")
+
+// netError satisfies the net Error interface.
+type netError struct {
+	msg       string
+	temporary bool
+	timeout   bool
+}
+
+func (e *netError) Error() string   { return e.msg }
+func (e *netError) Temporary() bool { return e.temporary }
+func (e *netError) Timeout() bool   { return e.timeout }
+
+// CloseError represents a close message.
+type CloseError struct {
+	// Code is defined in RFC 6455, section 11.7.
+	Code int
+
+	// Text is the optional text payload.
+	Text string
+}
+
+func (e *CloseError) Error() string {
+	s := []byte("websocket: close ")
+	s = strconv.AppendInt(s, int64(e.Code), 10)
+	switch e.Code {
+	case CloseNormalClosure:
+		s = append(s, " (normal)"...)
+	case CloseGoingAway:
+		s = append(s, " (going away)"...)
+	case CloseProtocolError:
+		s = append(s, " (protocol error)"...)
+	case CloseUnsupportedData:
+		s = append(s, " (unsupported data)"...)
+	case CloseNoStatusReceived:
+		s = append(s, " (no status)"...)
+	case CloseAbnormalClosure:
+		s = append(s, " (abnormal closure)"...)
+	case CloseInvalidFramePayloadData:
+		s = append(s, " (invalid payload data)"...)
+	case ClosePolicyViolation:
+		s = append(s, " (policy violation)"...)
+	case CloseMessageTooBig:
+		s = append(s, " (message too big)"...)
+	case CloseMandatoryExtension:
+		s = append(s, " (mandatory extension missing)"...)
+	case CloseInternalServerErr:
+		s = append(s, " (internal server error)"...)
+	case CloseTLSHandshake:
+		s = append(s, " (TLS handshake error)"...)
+	}
+	if e.Text != "" {
+		s = append(s, ": "...)
+		s = append(s, e.Text...)
+	}
+	return string(s)
+}
+
+// IsCloseError returns boolean indicating whether the error is a *CloseError
+// with one of the specified codes.
+func IsCloseError(err error, codes ...int) bool {
+	if e, ok := err.(*CloseError); ok {
+		for _, code := range codes {
+			if e.Code == code {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// IsUnexpectedCloseError returns boolean indicating whether the error is a
+// *CloseError with a code not in the list of expected codes.
+func IsUnexpectedCloseError(err error, expectedCodes ...int) bool {
+	if e, ok := err.(*CloseError); ok {
+		for _, code := range expectedCodes {
+			if e.Code == code {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}
+
+var (
+	errWriteTimeout        = &netError{msg: "websocket: write timeout", timeout: true, temporary: true}
+	errUnexpectedEOF       = &CloseError{Code: CloseAbnormalClosure, Text: io.ErrUnexpectedEOF.Error()}
+	errBadWriteOpCode      = errors.New("websocket: bad write message type")
+	errWriteClosed         = errors.New("websocket: write closed")
+	errInvalidControlFrame = errors.New("websocket: invalid control frame")
+)
+
+// maskRand is an io.Reader for generating mask bytes. The reader is initialized
+// to crypto/rand Reader. Tests swap the reader to a math/rand reader for
+// reproducible results.
+var maskRand = rand.Reader
+
+// newMaskKey returns a new 32 bit value for masking client frames.
+func newMaskKey() [4]byte {
+	var k [4]byte
+	_, _ = io.ReadFull(maskRand, k[:])
+	return k
+}
+
+func isControl(frameType int) bool {
+	return frameType == CloseMessage || frameType == PingMessage || frameType == PongMessage
+}
+
+func isData(frameType int) bool {
+	return frameType == TextMessage || frameType == BinaryMessage
+}
+
+var validReceivedCloseCodes = map[int]bool{
+	// see http://www.iana.org/assignments/websocket/websocket.xhtml#close-code-number
+
+	CloseNormalClosure:           true,
+	CloseGoingAway:               true,
+	CloseProtocolError:           true,
+	CloseUnsupportedData:         true,
+	CloseNoStatusReceived:        false,
+	CloseAbnormalClosure:         false,
+	CloseInvalidFramePayloadData: true,
+	ClosePolicyViolation:         true,
+	CloseMessageTooBig:           true,
+	CloseMandatoryExtension:      true,
+	CloseInternalServerErr:       true,
+	CloseServiceRestart:          true,
+	CloseTryAgainLater:           true,
+	CloseTLSHandshake:            false,
+}
+
+func isValidReceivedCloseCode(code int) bool {
+	return validReceivedCloseCodes[code] || (code >= 3000 && code <= 4999)
+}
+
+// BufferPool represents a pool of buffers. The *sync.Pool type satisfies this
+// interface.  The type of the value stored in a pool is not specified.
+type BufferPool interface {
+	// Get gets a value from the pool or returns nil if the pool is empty.
+	Get() interface{}
+	// Put adds a value to the pool.
+	Put(interface{})
+}
+
+// writePoolData is the type added to the write buffer pool. This wrapper is
+// used to prevent applications from peeking at and depending on the values
+// added to the pool.
+type writePoolData struct{ buf []byte }
+
+// The Conn type represents a WebSocket connection.
+type Conn struct {
+	conn        net.Conn
+	isServer    bool
+	subprotocol string
+
+	// Write fields
+	mu            chan struct{} // used as mutex to protect write to conn
+	writeBuf      []byte        // frame is constructed in this buffer.
+	writePool     BufferPool
+	writeBufSize  int
+	writeDeadline time.Time
+	writer        io.WriteCloser // the current writer returned to the application
+	isWriting     bool           // for best-effort concurrent write detection
+
+	writeErrMu sync.Mutex
+	writeErr   error
+
+	enableWriteCompression bool
+	compressionLevel       int
+	newCompressionWriter   func(io.WriteCloser, int) io.WriteCloser
+
+	// Read fields
+	reader  io.ReadCloser // the current reader returned to the application
+	readErr error
+	br      *bufio.Reader
+	// bytes remaining in current frame.
+	// set setReadRemaining to safely update this value and prevent overflow
+	readRemaining int64
+	readFinal     bool  // true the current message has more frames.
+	readLength    int64 // Message size.
+	readLimit     int64 // Maximum message size.
+	readMaskPos   int
+	readMaskKey   [4]byte
+	handlePong    func(string) error
+	handlePing    func(string) error
+	handleClose   func(int, string) error
+	readErrCount  int
+	messageReader *messageReader // the current low-level reader
+
+	readDecompress         bool // whether last read frame had RSV1 set
+	newDecompressionReader func(io.Reader) io.ReadCloser
+}
+
+func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int, writeBufferPool BufferPool, br *bufio.Reader, writeBuf []byte) *Conn {
+
+	if br == nil {
+		if readBufferSize == 0 {
+			readBufferSize = defaultReadBufferSize
+		} else if readBufferSize < maxControlFramePayloadSize {
+			// must be large enough for control frame
+			readBufferSize = maxControlFramePayloadSize
+		}
+		br = bufio.NewReaderSize(conn, readBufferSize)
+	}
+
+	if writeBufferSize <= 0 {
+		writeBufferSize = defaultWriteBufferSize
+	}
+	writeBufferSize += maxFrameHeaderSize
+
+	if writeBuf == nil && writeBufferPool == nil {
+		writeBuf = make([]byte, writeBufferSize)
+	}
+
+	mu := make(chan struct{}, 1)
+	mu <- struct{}{}
+	c := &Conn{
+		isServer:               isServer,
+		br:                     br,
+		conn:                   conn,
+		mu:                     mu,
+		readFinal:              true,
+		writeBuf:               writeBuf,
+		writePool:              writeBufferPool,
+		writeBufSize:           writeBufferSize,
+		enableWriteCompression: true,
+		compressionLevel:       defaultCompressionLevel,
+	}
+	c.SetCloseHandler(nil)
+	c.SetPingHandler(nil)
+	c.SetPongHandler(nil)
+	return c
+}
+
+// setReadRemaining tracks the number of bytes remaining on the connection. If n
+// overflows, an ErrReadLimit is returned.
+func (c *Conn) setReadRemaining(n int64) error {
+	if n < 0 {
+		return ErrReadLimit
+	}
+
+	c.readRemaining = n
+	return nil
+}
+
+// Subprotocol returns the negotiated protocol for the connection.
+func (c *Conn) Subprotocol() string {
+	return c.subprotocol
+}
+
+// Close closes the underlying network connection without sending or waiting
+// for a close message.
+func (c *Conn) Close() error {
+	return c.conn.Close()
+}
+
+// LocalAddr returns the local network address.
+func (c *Conn) LocalAddr() net.Addr {
+	return c.conn.LocalAddr()
+}
+
+// RemoteAddr returns the remote network address.
+func (c *Conn) RemoteAddr() net.Addr {
+	return c.conn.RemoteAddr()
+}
+
+// Write methods
+
+func (c *Conn) writeFatal(err error) error {
+	c.writeErrMu.Lock()
+	if c.writeErr == nil {
+		c.writeErr = err
+	}
+	c.writeErrMu.Unlock()
+	return err
+}
+
+func (c *Conn) read(n int) ([]byte, error) {
+	p, err := c.br.Peek(n)
+	if err == io.EOF {
+		err = errUnexpectedEOF
+	}
+	// Discard is guaranteed to succeed because the number of bytes to discard
+	// is less than or equal to the number of bytes buffered.
+	_, _ = c.br.Discard(len(p))
+	return p, err
+}
+
+func (c *Conn) write(frameType int, deadline time.Time, buf0, buf1 []byte) error {
+	<-c.mu
+	defer func() { c.mu <- struct{}{} }()
+
+	c.writeErrMu.Lock()
+	err := c.writeErr
+	c.writeErrMu.Unlock()
+	if err != nil {
+		return err
+	}
+
+	if err := c.conn.SetWriteDeadline(deadline); err != nil {
+		return c.writeFatal(err)
+	}
+	if len(buf1) == 0 {
+		_, err = c.conn.Write(buf0)
+	} else {
+		err = c.writeBufs(buf0, buf1)
+	}
+	if err != nil {
+		return c.writeFatal(err)
+	}
+	if frameType == CloseMessage {
+		_ = c.writeFatal(ErrCloseSent)
+	}
+	return nil
+}
+
+func (c *Conn) writeBufs(bufs ...[]byte) error {
+	b := net.Buffers(bufs)
+	_, err := b.WriteTo(c.conn)
+	return err
+}
+
+// WriteControl writes a control message with the given deadline. The allowed
+// message types are CloseMessage, PingMessage and PongMessage.
+func (c *Conn) WriteControl(messageType int, data []byte, deadline time.Time) error {
+	if !isControl(messageType) {
+		return errBadWriteOpCode
+	}
+	if len(data) > maxControlFramePayloadSize {
+		return errInvalidControlFrame
+	}
+
+	b0 := byte(messageType) | finalBit
+	b1 := byte(len(data))
+	if !c.isServer {
+		b1 |= maskBit
+	}
+
+	buf := make([]byte, 0, maxFrameHeaderSize+maxControlFramePayloadSize)
+	buf = append(buf, b0, b1)
+
+	if c.isServer {
+		buf = append(buf, data...)
+	} else {
+		key := newMaskKey()
+		buf = append(buf, key[:]...)
+		buf = append(buf, data...)
+		maskBytes(key, 0, buf[6:])
+	}
+
+	if deadline.IsZero() {
+		// No timeout for zero time.
+		<-c.mu
+	} else {
+		d := time.Until(deadline)
+		if d < 0 {
+			return errWriteTimeout
+		}
+		select {
+		case <-c.mu:
+		default:
+			timer := time.NewTimer(d)
+			select {
+			case <-c.mu:
+				timer.Stop()
+			case <-timer.C:
+				return errWriteTimeout
+			}
+		}
+	}
+
+	defer func() { c.mu <- struct{}{} }()
+
+	c.writeErrMu.Lock()
+	err := c.writeErr
+	c.writeErrMu.Unlock()
+	if err != nil {
+		return err
+	}
+
+	if err := c.conn.SetWriteDeadline(deadline); err != nil {
+		return c.writeFatal(err)
+	}
+	if _, err = c.conn.Write(buf); err != nil {
+		return c.writeFatal(err)
+	}
+	if messageType == CloseMessage {
+		_ = c.writeFatal(ErrCloseSent)
+	}
+	return err
+}
+
+// beginMessage prepares a connection and message writer for a new message.
+func (c *Conn) beginMessage(mw *messageWriter, messageType int) error {
+	// Close previous writer if not already closed by the application. It's
+	// probably better to return an error in this situation, but we cannot
+	// change this without breaking existing applications.
+	if c.writer != nil {
+		c.writer.Close()
+		c.writer = nil
+	}
+
+	if !isControl(messageType) && !isData(messageType) {
+		return errBadWriteOpCode
+	}
+
+	c.writeErrMu.Lock()
+	err := c.writeErr
+	c.writeErrMu.Unlock()
+	if err != nil {
+		return err
+	}
+
+	mw.c = c
+	mw.frameType = messageType
+	mw.pos = maxFrameHeaderSize
+
+	if c.writeBuf == nil {
+		wpd, ok := c.writePool.Get().(writePoolData)
+		if ok {
+			c.writeBuf = wpd.buf
+		} else {
+			c.writeBuf = make([]byte, c.writeBufSize)
+		}
+	}
+	return nil
+}
+
+// NextWriter returns a writer for the next message to send. The writer's Close
+// method flushes the complete message to the network.
+//
+// There can be at most one open writer on a connection. NextWriter closes the
+// previous writer if the application has not already done so.
+//
+// All message types (TextMessage, BinaryMessage, CloseMessage, PingMessage and
+// PongMessage) are supported.
+func (c *Conn) NextWriter(messageType int) (io.WriteCloser, error) {
+	var mw messageWriter
+	if err := c.beginMessage(&mw, messageType); err != nil {
+		return nil, err
+	}
+	c.writer = &mw
+	if c.newCompressionWriter != nil && c.enableWriteCompression && isData(messageType) {
+		w := c.newCompressionWriter(c.writer, c.compressionLevel)
+		mw.compress = true
+		c.writer = w
+	}
+	return c.writer, nil
+}
+
+type messageWriter struct {
+	c         *Conn
+	compress  bool // whether next call to flushFrame should set RSV1
+	pos       int  // end of data in writeBuf.
+	frameType int  // type of the current frame.
+	err       error
+}
+
+func (w *messageWriter) endMessage(err error) error {
+	if w.err != nil {
+		return err
+	}
+	c := w.c
+	w.err = err
+	c.writer = nil
+	if c.writePool != nil {
+		c.writePool.Put(writePoolData{buf: c.writeBuf})
+		c.writeBuf = nil
+	}
+	return err
+}
+
+// flushFrame writes buffered data and extra as a frame to the network. The
+// final argument indicates that this is the last frame in the message.
+func (w *messageWriter) flushFrame(final bool, extra []byte) error {
+	c := w.c
+	length := w.pos - maxFrameHeaderSize + len(extra)
+
+	// Check for invalid control frames.
+	if isControl(w.frameType) &&
+		(!final || length > maxControlFramePayloadSize) {
+		return w.endMessage(errInvalidControlFrame)
+	}
+
+	b0 := byte(w.frameType)
+	if final {
+		b0 |= finalBit
+	}
+	if w.compress {
+		b0 |= rsv1Bit
+	}
+	w.compress = false
+
+	b1 := byte(0)
+	if !c.isServer {
+		b1 |= maskBit
+	}
+
+	// Assume that the frame starts at beginning of c.writeBuf.
+	framePos := 0
+	if c.isServer {
+		// Adjust up if mask not included in the header.
+		framePos = 4
+	}
+
+	switch {
+	case length >= 65536:
+		c.writeBuf[framePos] = b0
+		c.writeBuf[framePos+1] = b1 | 127
+		binary.BigEndian.PutUint64(c.writeBuf[framePos+2:], uint64(length))
+	case length > 125:
+		framePos += 6
+		c.writeBuf[framePos] = b0
+		c.writeBuf[framePos+1] = b1 | 126
+		binary.BigEndian.PutUint16(c.writeBuf[framePos+2:], uint16(length))
+	default:
+		framePos += 8
+		c.writeBuf[framePos] = b0
+		c.writeBuf[framePos+1] = b1 | byte(length)
+	}
+
+	if !c.isServer {
+		key := newMaskKey()
+		copy(c.writeBuf[maxFrameHeaderSize-4:], key[:])
+		maskBytes(key, 0, c.writeBuf[maxFrameHeaderSize:w.pos])
+		if len(extra) > 0 {
+			return w.endMessage(c.writeFatal(errors.New("websocket: internal error, extra used in client mode")))
+		}
+	}
+
+	// Write the buffers to the connection with best-effort detection of
+	// concurrent writes. See the concurrency section in the package
+	// documentation for more info.
+
+	if c.isWriting {
+		panic("concurrent write to websocket connection")
+	}
+	c.isWriting = true
+
+	err := c.write(w.frameType, c.writeDeadline, c.writeBuf[framePos:w.pos], extra)
+
+	if !c.isWriting {
+		panic("concurrent write to websocket connection")
+	}
+	c.isWriting = false
+
+	if err != nil {
+		return w.endMessage(err)
+	}
+
+	if final {
+		_ = w.endMessage(errWriteClosed)
+		return nil
+	}
+
+	// Setup for next frame.
+	w.pos = maxFrameHeaderSize
+	w.frameType = continuationFrame
+	return nil
+}
+
+func (w *messageWriter) ncopy(max int) (int, error) {
+	n := len(w.c.writeBuf) - w.pos
+	if n <= 0 {
+		if err := w.flushFrame(false, nil); err != nil {
+			return 0, err
+		}
+		n = len(w.c.writeBuf) - w.pos
+	}
+	if n > max {
+		n = max
+	}
+	return n, nil
+}
+
+func (w *messageWriter) Write(p []byte) (int, error) {
+	if w.err != nil {
+		return 0, w.err
+	}
+
+	if len(p) > 2*len(w.c.writeBuf) && w.c.isServer {
+		// Don't buffer large messages.
+		err := w.flushFrame(false, p)
+		if err != nil {
+			return 0, err
+		}
+		return len(p), nil
+	}
+
+	nn := len(p)
+	for len(p) > 0 {
+		n, err := w.ncopy(len(p))
+		if err != nil {
+			return 0, err
+		}
+		copy(w.c.writeBuf[w.pos:], p[:n])
+		w.pos += n
+		p = p[n:]
+	}
+	return nn, nil
+}
+
+func (w *messageWriter) WriteString(p string) (int, error) {
+	if w.err != nil {
+		return 0, w.err
+	}
+
+	nn := len(p)
+	for len(p) > 0 {
+		n, err := w.ncopy(len(p))
+		if err != nil {
+			return 0, err
+		}
+		copy(w.c.writeBuf[w.pos:], p[:n])
+		w.pos += n
+		p = p[n:]
+	}
+	return nn, nil
+}
+
+func (w *messageWriter) ReadFrom(r io.Reader) (nn int64, err error) {
+	if w.err != nil {
+		return 0, w.err
+	}
+	for {
+		if w.pos == len(w.c.writeBuf) {
+			err = w.flushFrame(false, nil)
+			if err != nil {
+				break
+			}
+		}
+		var n int
+		n, err = r.Read(w.c.writeBuf[w.pos:])
+		w.pos += n
+		nn += int64(n)
+		if err != nil {
+			if err == io.EOF {
+				err = nil
+			}
+			break
+		}
+	}
+	return nn, err
+}
+
+func (w *messageWriter) Close() error {
+	if w.err != nil {
+		return w.err
+	}
+	return w.flushFrame(true, nil)
+}
+
+// WritePreparedMessage writes prepared message into connection.
+func (c *Conn) WritePreparedMessage(pm *PreparedMessage) error {
+	frameType, frameData, err := pm.frame(prepareKey{
+		isServer:         c.isServer,
+		compress:         c.newCompressionWriter != nil && c.enableWriteCompression && isData(pm.messageType),
+		compressionLevel: c.compressionLevel,
+	})
+	if err != nil {
+		return err
+	}
+	if c.isWriting {
+		panic("concurrent write to websocket connection")
+	}
+	c.isWriting = true
+	err = c.write(frameType, c.writeDeadline, frameData, nil)
+	if !c.isWriting {
+		panic("concurrent write to websocket connection")
+	}
+	c.isWriting = false
+	return err
+}
+
+// WriteMessage is a helper method for getting a writer using NextWriter,
+// writing the message and closing the writer.
+func (c *Conn) WriteMessage(messageType int, data []byte) error {
+
+	if c.isServer && (c.newCompressionWriter == nil || !c.enableWriteCompression) {
+		// Fast path with no allocations and single frame.
+
+		var mw messageWriter
+		if err := c.beginMessage(&mw, messageType); err != nil {
+			return err
+		}
+		n := copy(c.writeBuf[mw.pos:], data)
+		mw.pos += n
+		data = data[n:]
+		return mw.flushFrame(true, data)
+	}
+
+	w, err := c.NextWriter(messageType)
+	if err != nil {
+		return err
+	}
+	if _, err = w.Write(data); err != nil {
+		return err
+	}
+	return w.Close()
+}
+
+// SetWriteDeadline sets the write deadline on the underlying network
+// connection. After a write has timed out, the websocket state is corrupt and
+// all future writes will return an error. A zero value for t means writes will
+// not time out.
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	c.writeDeadline = t
+	return nil
+}
+
+// Read methods
+
+func (c *Conn) advanceFrame() (int, error) {
+	// 1. Skip remainder of previous frame.
+
+	if c.readRemaining > 0 {
+		if _, err := io.CopyN(io.Discard, c.br, c.readRemaining); err != nil {
+			return noFrame, err
+		}
+	}
+
+	// 2. Read and parse first two bytes of frame header.
+	// To aid debugging, collect and report all errors in the first two bytes
+	// of the header.
+
+	var errors []string
+
+	p, err := c.read(2)
+	if err != nil {
+		return noFrame, err
+	}
+
+	frameType := int(p[0] & 0xf)
+	final := p[0]&finalBit != 0
+	rsv1 := p[0]&rsv1Bit != 0
+	rsv2 := p[0]&rsv2Bit != 0
+	rsv3 := p[0]&rsv3Bit != 0
+	mask := p[1]&maskBit != 0
+	_ = c.setReadRemaining(int64(p[1] & 0x7f)) // will not fail because argument is >= 0
+
+	c.readDecompress = false
+	if rsv1 {
+		if c.newDecompressionReader != nil {
+			c.readDecompress = true
+		} else {
+			errors = append(errors, "RSV1 set")
+		}
+	}
+
+	if rsv2 {
+		errors = append(errors, "RSV2 set")
+	}
+
+	if rsv3 {
+		errors = append(errors, "RSV3 set")
+	}
+
+	switch frameType {
+	case CloseMessage, PingMessage, PongMessage:
+		if c.readRemaining > maxControlFramePayloadSize {
+			errors = append(errors, "len > 125 for control")
+		}
+		if !final {
+			errors = append(errors, "FIN not set on control")
+		}
+	case TextMessage, BinaryMessage:
+		if !c.readFinal {
+			errors = append(errors, "data before FIN")
+		}
+		c.readFinal = final
+	case continuationFrame:
+		if c.readFinal {
+			errors = append(errors, "continuation after FIN")
+		}
+		c.readFinal = final
+	default:
+		errors = append(errors, "bad opcode "+strconv.Itoa(frameType))
+	}
+
+	if mask != c.isServer {
+		errors = append(errors, "bad MASK")
+	}
+
+	if len(errors) > 0 {
+		return noFrame, c.handleProtocolError(strings.Join(errors, ", "))
+	}
+
+	// 3. Read and parse frame length as per
+	// https://tools.ietf.org/html/rfc6455#section-5.2
+	//
+	// The length of the "Payload data", in bytes: if 0-125, that is the payload
+	// length.
+	// - If 126, the following 2 bytes interpreted as a 16-bit unsigned
+	// integer are the payload length.
+	// - If 127, the following 8 bytes interpreted as
+	// a 64-bit unsigned integer (the most significant bit MUST be 0) are the
+	// payload length. Multibyte length quantities are expressed in network byte
+	// order.
+
+	switch c.readRemaining {
+	case 126:
+		p, err := c.read(2)
+		if err != nil {
+			return noFrame, err
+		}
+
+		if err := c.setReadRemaining(int64(binary.BigEndian.Uint16(p))); err != nil {
+			return noFrame, err
+		}
+	case 127:
+		p, err := c.read(8)
+		if err != nil {
+			return noFrame, err
+		}
+
+		if err := c.setReadRemaining(int64(binary.BigEndian.Uint64(p))); err != nil {
+			return noFrame, err
+		}
+	}
+
+	// 4. Handle frame masking.
+
+	if mask {
+		c.readMaskPos = 0
+		p, err := c.read(len(c.readMaskKey))
+		if err != nil {
+			return noFrame, err
+		}
+		copy(c.readMaskKey[:], p)
+	}
+
+	// 5. For text and binary messages, enforce read limit and return.
+
+	if frameType == continuationFrame || frameType == TextMessage || frameType == BinaryMessage {
+
+		c.readLength += c.readRemaining
+		// Don't allow readLength to overflow in the presence of a large readRemaining
+		// counter.
+		if c.readLength < 0 {
+			return noFrame, ErrReadLimit
+		}
+
+		if c.readLimit > 0 && c.readLength > c.readLimit {
+			// Make a best effort to send a close message describing the problem.
+			_ = c.WriteControl(CloseMessage, FormatCloseMessage(CloseMessageTooBig, ""), time.Now().Add(writeWait))
+			return noFrame, ErrReadLimit
+		}
+
+		return frameType, nil
+	}
+
+	// 6. Read control frame payload.
+
+	var payload []byte
+	if c.readRemaining > 0 {
+		payload, err = c.read(int(c.readRemaining))
+		_ = c.setReadRemaining(0) // will not fail because argument is >= 0
+		if err != nil {
+			return noFrame, err
+		}
+		if c.isServer {
+			maskBytes(c.readMaskKey, 0, payload)
+		}
+	}
+
+	// 7. Process control frame payload.
+
+	switch frameType {
+	case PongMessage:
+		if err := c.handlePong(string(payload)); err != nil {
+			return noFrame, err
+		}
+	case PingMessage:
+		if err := c.handlePing(string(payload)); err != nil {
+			return noFrame, err
+		}
+	case CloseMessage:
+		closeCode := CloseNoStatusReceived
+		closeText := ""
+		if len(payload) >= 2 {
+			closeCode = int(binary.BigEndian.Uint16(payload))
+			if !isValidReceivedCloseCode(closeCode) {
+				return noFrame, c.handleProtocolError("bad close code " + strconv.Itoa(closeCode))
+			}
+			closeText = string(payload[2:])
+			if !utf8.ValidString(closeText) {
+				return noFrame, c.handleProtocolError("invalid utf8 payload in close frame")
+			}
+		}
+		if err := c.handleClose(closeCode, closeText); err != nil {
+			return noFrame, err
+		}
+		return noFrame, &CloseError{Code: closeCode, Text: closeText}
+	}
+
+	return frameType, nil
+}
+
+func (c *Conn) handleProtocolError(message string) error {
+	data := FormatCloseMessage(CloseProtocolError, message)
+	if len(data) > maxControlFramePayloadSize {
+		data = data[:maxControlFramePayloadSize]
+	}
+	// Make a best effor to send a close message describing the problem.
+	_ = c.WriteControl(CloseMessage, data, time.Now().Add(writeWait))
+	return errors.New("websocket: " + message)
+}
+
+// NextReader returns the next data message received from the peer. The
+// returned messageType is either TextMessage or BinaryMessage.
+//
+// There can be at most one open reader on a connection. NextReader discards
+// the previous message if the application has not already consumed it.
+//
+// Applications must break out of the application's read loop when this method
+// returns a non-nil error value. Errors returned from this method are
+// permanent. Once this method returns a non-nil error, all subsequent calls to
+// this method return the same error.
+func (c *Conn) NextReader() (messageType int, r io.Reader, err error) {
+	// Close previous reader, only relevant for decompression.
+	if c.reader != nil {
+		c.reader.Close()
+		c.reader = nil
+	}
+
+	c.messageReader = nil
+	c.readLength = 0
+
+	for c.readErr == nil {
+		frameType, err := c.advanceFrame()
+		if err != nil {
+			c.readErr = err
+			break
+		}
+
+		if frameType == TextMessage || frameType == BinaryMessage {
+			c.messageReader = &messageReader{c}
+			c.reader = c.messageReader
+			if c.readDecompress {
+				c.reader = c.newDecompressionReader(c.reader)
+			}
+			return frameType, c.reader, nil
+		}
+	}
+
+	// Applications that do handle the error returned from this method spin in
+	// tight loop on connection failure. To help application developers detect
+	// this error, panic on repeated reads to the failed connection.
+	c.readErrCount++
+	if c.readErrCount >= 1000 {
+		panic("repeated read on failed websocket connection")
+	}
+
+	return noFrame, nil, c.readErr
+}
+
+type messageReader struct{ c *Conn }
+
+func (r *messageReader) Read(b []byte) (int, error) {
+	c := r.c
+	if c.messageReader != r {
+		return 0, io.EOF
+	}
+
+	for c.readErr == nil {
+
+		if c.readRemaining > 0 {
+			if int64(len(b)) > c.readRemaining {
+				b = b[:c.readRemaining]
+			}
+			n, err := c.br.Read(b)
+			c.readErr = err
+			if c.isServer {
+				c.readMaskPos = maskBytes(c.readMaskKey, c.readMaskPos, b[:n])
+			}
+			rem := c.readRemaining
+			rem -= int64(n)
+			_ = c.setReadRemaining(rem) // rem is guaranteed to be >= 0
+			if c.readRemaining > 0 && c.readErr == io.EOF {
+				c.readErr = errUnexpectedEOF
+			}
+			return n, c.readErr
+		}
+
+		if c.readFinal {
+			c.messageReader = nil
+			return 0, io.EOF
+		}
+
+		frameType, err := c.advanceFrame()
+		switch {
+		case err != nil:
+			c.readErr = err
+		case frameType == TextMessage || frameType == BinaryMessage:
+			c.readErr = errors.New("websocket: internal error, unexpected text or binary in Reader")
+		}
+	}
+
+	err := c.readErr
+	if err == io.EOF && c.messageReader == r {
+		err = errUnexpectedEOF
+	}
+	return 0, err
+}
+
+func (r *messageReader) Close() error {
+	return nil
+}
+
+// ReadMessage is a helper method for getting a reader using NextReader and
+// reading from that reader to a buffer.
+func (c *Conn) ReadMessage() (messageType int, p []byte, err error) {
+	var r io.Reader
+	messageType, r, err = c.NextReader()
+	if err != nil {
+		return messageType, nil, err
+	}
+	p, err = io.ReadAll(r)
+	return messageType, p, err
+}
+
+// SetReadDeadline sets the read deadline on the underlying network connection.
+// After a read has timed out, the websocket connection state is corrupt and
+// all future reads will return an error. A zero value for t means reads will
+// not time out.
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	return c.conn.SetReadDeadline(t)
+}
+
+// SetReadLimit sets the maximum size in bytes for a message read from the peer. If a
+// message exceeds the limit, the connection sends a close message to the peer
+// and returns ErrReadLimit to the application.
+func (c *Conn) SetReadLimit(limit int64) {
+	c.readLimit = limit
+}
+
+// CloseHandler returns the current close handler
+func (c *Conn) CloseHandler() func(code int, text string) error {
+	return c.handleClose
+}
+
+// SetCloseHandler sets the handler for close messages received from the peer.
+// The code argument to h is the received close code or CloseNoStatusReceived
+// if the close message is empty. The default close handler sends a close
+// message back to the peer.
+//
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// close messages as described in the section on Control Messages above.
+//
+// The connection read methods return a CloseError when a close message is
+// received. Most applications should handle close messages as part of their
+// normal error handling. Applications should only set a close handler when the
+// application must perform some action before sending a close message back to
+// the peer.
+func (c *Conn) SetCloseHandler(h func(code int, text string) error) {
+	if h == nil {
+		h = func(code int, text string) error {
+			message := FormatCloseMessage(code, "")
+			// Make a best effor to send the close message.
+			_ = c.WriteControl(CloseMessage, message, time.Now().Add(writeWait))
+			return nil
+		}
+	}
+	c.handleClose = h
+}
+
+// PingHandler returns the current ping handler
+func (c *Conn) PingHandler() func(appData string) error {
+	return c.handlePing
+}
+
+// SetPingHandler sets the handler for ping messages received from the peer.
+// The appData argument to h is the PING message application data. The default
+// ping handler sends a pong to the peer.
+//
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// ping messages as described in the section on Control Messages above.
+func (c *Conn) SetPingHandler(h func(appData string) error) {
+	if h == nil {
+		h = func(message string) error {
+			// Make a best effort to send the pong message.
+			_ = c.WriteControl(PongMessage, []byte(message), time.Now().Add(writeWait))
+			return nil
+		}
+	}
+	c.handlePing = h
+}
+
+// PongHandler returns the current pong handler
+func (c *Conn) PongHandler() func(appData string) error {
+	return c.handlePong
+}
+
+// SetPongHandler sets the handler for pong messages received from the peer.
+// The appData argument to h is the PONG message application data. The default
+// pong handler does nothing.
+//
+// The handler function is called from the NextReader, ReadMessage and message
+// reader Read methods. The application must read the connection to process
+// pong messages as described in the section on Control Messages above.
+func (c *Conn) SetPongHandler(h func(appData string) error) {
+	if h == nil {
+		h = func(string) error { return nil }
+	}
+	c.handlePong = h
+}
+
+// NetConn returns the underlying connection that is wrapped by c.
+// Note that writing to or reading from this connection directly will corrupt the
+// WebSocket connection.
+func (c *Conn) NetConn() net.Conn {
+	return c.conn
+}
+
+// UnderlyingConn returns the internal net.Conn. This can be used to further
+// modifications to connection specific flags.
+// Deprecated: Use the NetConn method.
+func (c *Conn) UnderlyingConn() net.Conn {
+	return c.conn
+}
+
+// EnableWriteCompression enables and disables write compression of
+// subsequent text and binary messages. This function is a noop if
+// compression was not negotiated with the peer.
+func (c *Conn) EnableWriteCompression(enable bool) {
+	c.enableWriteCompression = enable
+}
+
+// SetCompressionLevel sets the flate compression level for subsequent text and
+// binary messages. This function is a noop if compression was not negotiated
+// with the peer. See the compress/flate package for a description of
+// compression levels.
+func (c *Conn) SetCompressionLevel(level int) error {
+	if !isValidCompressionLevel(level) {
+		return errors.New("websocket: invalid compression level")
+	}
+	c.compressionLevel = level
+	return nil
+}
+
+// FormatCloseMessage formats closeCode and text as a WebSocket close message.
+// An empty message is returned for code CloseNoStatusReceived.
+func FormatCloseMessage(closeCode int, text string) []byte {
+	if closeCode == CloseNoStatusReceived {
+		// Return empty message because it's illegal to send
+		// CloseNoStatusReceived. Return non-nil value in case application
+		// checks for nil.
+		return []byte{}
+	}
+	buf := make([]byte, 2+len(text))
+	binary.BigEndian.PutUint16(buf, uint16(closeCode))
+	copy(buf[2:], text)
+	return buf
+}
+// Copyright 2013 The Gorilla WebSocket 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 websocket implements the WebSocket protocol defined in RFC 6455.
+//
+// Overview
+//
+// The Conn type represents a WebSocket connection. A server application calls
+// the Upgrader.Upgrade method from an HTTP request handler to get a *Conn:
+//
+//  var upgrader = websocket.Upgrader{
+//      ReadBufferSize:  1024,
+//      WriteBufferSize: 1024,
+//  }
+//
+//  func handler(w http.ResponseWriter, r *http.Request) {
+//      conn, err := upgrader.Upgrade(w, r, nil)
+//      if err != nil {
+//          log.Println(err)
+//          return
+//      }
+//      ... Use conn to send and receive messages.
+//  }
+//
+// Call the connection's WriteMessage and ReadMessage methods to send and
+// receive messages as a slice of bytes. This snippet of code shows how to echo
+// messages using these methods:
+//
+//  for {
+//      messageType, p, err := conn.ReadMessage()
+//      if err != nil {
+//          log.Println(err)
+//          return
+//      }
+//      if err := conn.WriteMessage(messageType, p); err != nil {
+//          log.Println(err)
+//          return
+//      }
+//  }
+//
+// In above snippet of code, p is a []byte and messageType is an int with value
+// websocket.BinaryMessage or websocket.TextMessage.
+//
+// An application can also send and receive messages using the io.WriteCloser
+// and io.Reader interfaces. To send a message, call the connection NextWriter
+// method to get an io.WriteCloser, write the message to the writer and close
+// the writer when done. To receive a message, call the connection NextReader
+// method to get an io.Reader and read until io.EOF is returned. This snippet
+// shows how to echo messages using the NextWriter and NextReader methods:
+//
+//  for {
+//      messageType, r, err := conn.NextReader()
+//      if err != nil {
+//          return
+//      }
+//      w, err := conn.NextWriter(messageType)
+//      if err != nil {
+//          return err
+//      }
+//      if _, err := io.Copy(w, r); err != nil {
+//          return err
+//      }
+//      if err := w.Close(); err != nil {
+//          return err
+//      }
+//  }
+//
+// Data Messages
+//
+// The WebSocket protocol distinguishes between text and binary data messages.
+// Text messages are interpreted as UTF-8 encoded text. The interpretation of
+// binary messages is left to the application.
+//
+// This package uses the TextMessage and BinaryMessage integer constants to
+// identify the two data message types. The ReadMessage and NextReader methods
+// return the type of the received message. The messageType argument to the
+// WriteMessage and NextWriter methods specifies the type of a sent message.
+//
+// It is the application's responsibility to ensure that text messages are
+// valid UTF-8 encoded text.
+//
+// Control Messages
+//
+// The WebSocket protocol defines three types of control messages: close, ping
+// and pong. Call the connection WriteControl, WriteMessage or NextWriter
+// methods to send a control message to the peer.
+//
+// Connections handle received close messages by calling the handler function
+// set with the SetCloseHandler method and by returning a *CloseError from the
+// NextReader, ReadMessage or the message Read method. The default close
+// handler sends a close message to the peer.
+//
+// Connections handle received ping messages by calling the handler function
+// set with the SetPingHandler method. The default ping handler sends a pong
+// message to the peer.
+//
+// Connections handle received pong messages by calling the handler function
+// set with the SetPongHandler method. The default pong handler does nothing.
+// If an application sends ping messages, then the application should set a
+// pong handler to receive the corresponding pong.
+//
+// The control message handler functions are called from the NextReader,
+// ReadMessage and message reader Read methods. The default close and ping
+// handlers can block these methods for a short time when the handler writes to
+// the connection.
+//
+// The application must read the connection to process close, ping and pong
+// messages sent from the peer. If the application is not otherwise interested
+// in messages from the peer, then the application should start a goroutine to
+// read and discard messages from the peer. A simple example is:
+//
+//  func readLoop(c *websocket.Conn) {
+//      for {
+//          if _, _, err := c.NextReader(); err != nil {
+//              c.Close()
+//              break
+//          }
+//      }
+//  }
+//
+// Concurrency
+//
+// Connections support one concurrent reader and one concurrent writer.
+//
+// Applications are responsible for ensuring that no more than one goroutine
+// calls the write methods (NextWriter, SetWriteDeadline, WriteMessage,
+// WriteJSON, EnableWriteCompression, SetCompressionLevel) concurrently and
+// that no more than one goroutine calls the read methods (NextReader,
+// SetReadDeadline, ReadMessage, ReadJSON, SetPongHandler, SetPingHandler)
+// concurrently.
+//
+// The Close and WriteControl methods can be called concurrently with all other
+// methods.
+//
+// Origin Considerations
+//
+// Web browsers allow Javascript applications to open a WebSocket connection to
+// any host. It's up to the server to enforce an origin policy using the Origin
+// request header sent by the browser.
+//
+// The Upgrader calls the function specified in the CheckOrigin field to check
+// the origin. If the CheckOrigin function returns false, then the Upgrade
+// method fails the WebSocket handshake with HTTP status 403.
+//
+// If the CheckOrigin field is nil, then the Upgrader uses a safe default: fail
+// the handshake if the Origin request header is present and the Origin host is
+// not equal to the Host request header.
+//
+// The deprecated package-level Upgrade function does not perform origin
+// checking. The application is responsible for checking the Origin header
+// before calling the Upgrade function.
+//
+// Buffers
+//
+// Connections buffer network input and output to reduce the number
+// of system calls when reading or writing messages.
+//
+// Write buffers are also used for constructing WebSocket frames. See RFC 6455,
+// Section 5 for a discussion of message framing. A WebSocket frame header is
+// written to the network each time a write buffer is flushed to the network.
+// Decreasing the size of the write buffer can increase the amount of framing
+// overhead on the connection.
+//
+// The buffer sizes in bytes are specified by the ReadBufferSize and
+// WriteBufferSize fields in the Dialer and Upgrader. The Dialer uses a default
+// size of 4096 when a buffer size field is set to zero. The Upgrader reuses
+// buffers created by the HTTP server when a buffer size field is set to zero.
+// The HTTP server buffers have a size of 4096 at the time of this writing.
+//
+// The buffer sizes do not limit the size of a message that can be read or
+// written by a connection.
+//
+// Buffers are held for the lifetime of the connection by default. If the
+// Dialer or Upgrader WriteBufferPool field is set, then a connection holds the
+// write buffer only when writing a message.
+//
+// Applications should tune the buffer sizes to balance memory use and
+// performance. Increasing the buffer size uses more memory, but can reduce the
+// number of system calls to read or write the network. In the case of writing,
+// increasing the buffer size can reduce the number of frame headers written to
+// the network.
+//
+// Some guidelines for setting buffer parameters are:
+//
+// Limit the buffer sizes to the maximum expected message size. Buffers larger
+// than the largest message do not provide any benefit.
+//
+// Depending on the distribution of message sizes, setting the buffer size to
+// a value less than the maximum expected message size can greatly reduce memory
+// use with a small impact on performance. Here's an example: If 99% of the
+// messages are smaller than 256 bytes and the maximum message size is 512
+// bytes, then a buffer size of 256 bytes will result in 1.01 more system calls
+// than a buffer size of 512 bytes. The memory savings is 50%.
+//
+// A write buffer pool is useful when the application has a modest number
+// writes over a large number of connections. when buffers are pooled, a larger
+// buffer size has a reduced impact on total memory use and has the benefit of
+// reducing system calls and frame overhead.
+//
+// Compression EXPERIMENTAL
+//
+// Per message compression extensions (RFC 7692) are experimentally supported
+// by this package in a limited capacity. Setting the EnableCompression option
+// to true in Dialer or Upgrader will attempt to negotiate per message deflate
+// support.
+//
+//  var upgrader = websocket.Upgrader{
+//      EnableCompression: true,
+//  }
+//
+// If compression was successfully negotiated with the connection's peer, any
+// message received in compressed form will be automatically decompressed.
+// All Read methods will return uncompressed bytes.
+//
+// Per message compression of messages written to a connection can be enabled
+// or disabled by calling the corresponding Conn method:
+//
+//  conn.EnableWriteCompression(false)
+//
+// Currently this package does not support compression with "context takeover".
+// This means that messages must be compressed and decompressed in isolation,
+// without retaining sliding window or dictionary state across messages. For
+// more details refer to RFC 7692.
+//
+// Use of compression is experimental and may result in decreased performance.
+
+// Copyright 2019 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+// JoinMessages concatenates received messages to create a single io.Reader.
+// The string term is appended to each message. The returned reader does not
+// support concurrent calls to the Read method.
+func JoinMessages(c *Conn, term string) io.Reader {
+	return &joinReader{c: c, term: term}
+}
+
+type joinReader struct {
+	c    *Conn
+	term string
+	r    io.Reader
+}
+
+func (r *joinReader) Read(p []byte) (int, error) {
+	if r.r == nil {
+		var err error
+		_, r.r, err = r.c.NextReader()
+		if err != nil {
+			return 0, err
+		}
+		if r.term != "" {
+			r.r = io.MultiReader(r.r, strings.NewReader(r.term))
+		}
+	}
+	n, err := r.r.Read(p)
+	if err == io.EOF {
+		err = nil
+		r.r = nil
+	}
+	return n, err
+}
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+// WriteJSON writes the JSON encoding of v as a message.
+//
+// Deprecated: Use c.WriteJSON instead.
+func WriteJSON(c *Conn, v interface{}) error {
+	return c.WriteJSON(v)
+}
+
+// WriteJSON writes the JSON encoding of v as a message.
+//
+// See the documentation for encoding/json Marshal for details about the
+// conversion of Go values to JSON.
+func (c *Conn) WriteJSON(v interface{}) error {
+	w, err := c.NextWriter(TextMessage)
+	if err != nil {
+		return err
+	}
+	err1 := json.NewEncoder(w).Encode(v)
+	err2 := w.Close()
+	if err1 != nil {
+		return err1
+	}
+	return err2
+}
+
+// ReadJSON reads the next JSON-encoded message from the connection and stores
+// it in the value pointed to by v.
+//
+// Deprecated: Use c.ReadJSON instead.
+func ReadJSON(c *Conn, v interface{}) error {
+	return c.ReadJSON(v)
+}
+
+// ReadJSON reads the next JSON-encoded message from the connection and stores
+// it in the value pointed to by v.
+//
+// See the documentation for the encoding/json Unmarshal function for details
+// about the conversion of JSON to a Go value.
+func (c *Conn) ReadJSON(v interface{}) error {
+	_, r, err := c.NextReader()
+	if err != nil {
+		return err
+	}
+	err = json.NewDecoder(r).Decode(v)
+	if err == io.EOF {
+		// One value is expected in the message.
+		err = io.ErrUnexpectedEOF
+	}
+	return err
+}
+// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.  Use of
+// this source code is governed by a BSD-style license that can be found in the
+// LICENSE file.
+
+/// go:build !appengine //  +build !appengine
+
+
+const wordSize = int(unsafe.Sizeof(uintptr(0)))
+
+func maskBytesUnsafe(key [4]byte, pos int, b []byte) int {
+	// Mask one byte at a time for small buffers.
+	if len(b) < 2*wordSize {
+		for i := range b {
+			b[i] ^= key[pos&3]
+			pos++
+		}
+		return pos & 3
+	}
+
+	// Mask one byte at a time to word boundary.
+	if n := int(uintptr(unsafe.Pointer(&b[0]))) % wordSize; n != 0 {
+		n = wordSize - n
+		for i := range b[:n] {
+			b[i] ^= key[pos&3]
+			pos++
+		}
+		b = b[n:]
+	}
+
+	// Create aligned word size key.
+	var k [wordSize]byte
+	for i := range k {
+		k[i] = key[(pos+i)&3]
+	}
+	kw := *(*uintptr)(unsafe.Pointer(&k))
+
+	// Mask one word at a time.
+	n := (len(b) / wordSize) * wordSize
+	for i := 0; i < n; i += wordSize {
+		*(*uintptr)(unsafe.Pointer(uintptr(unsafe.Pointer(&b[0])) + uintptr(i))) ^= kw
+	}
+
+	// Mask one byte at a time for remaining bytes.
+	b = b[n:]
+	for i := range b {
+		b[i] ^= key[pos&3]
+		pos++
+	}
+
+	return pos & 3
+}
+// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.  Use of
+// this source code is governed by a BSD-style license that can be found in the
+// LICENSE file.
+
+/// go:build appengine // +build appengine
+
+
+func maskBytes(key [4]byte, pos int, b []byte) int {
+	for i := range b {
+		b[i] ^= key[pos&3]
+		pos++
+	}
+	return pos & 3
+}
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+// PreparedMessage caches on the wire representations of a message payload.
+// Use PreparedMessage to efficiently send a message payload to multiple
+// connections. PreparedMessage is especially useful when compression is used
+// because the CPU and memory expensive compression operation can be executed
+// once for a given set of compression options.
+type PreparedMessage struct {
+	messageType int
+	data        []byte
+	mu          sync.Mutex
+	frames      map[prepareKey]*preparedFrame
+}
+
+// prepareKey defines a unique set of options to cache prepared frames in PreparedMessage.
+type prepareKey struct {
+	isServer         bool
+	compress         bool
+	compressionLevel int
+}
+
+// preparedFrame contains data in wire representation.
+type preparedFrame struct {
+	once sync.Once
+	data []byte
+}
+
+// NewPreparedMessage returns an initialized PreparedMessage. You can then send
+// it to connection using WritePreparedMessage method. Valid wire
+// representation will be calculated lazily only once for a set of current
+// connection options.
+func NewPreparedMessage(messageType int, data []byte) (*PreparedMessage, error) {
+	pm := &PreparedMessage{
+		messageType: messageType,
+		frames:      make(map[prepareKey]*preparedFrame),
+		data:        data,
+	}
+
+	// Prepare a plain server frame.
+	_, frameData, err := pm.frame(prepareKey{isServer: true, compress: false})
+	if err != nil {
+		return nil, err
+	}
+
+	// To protect against caller modifying the data argument, remember the data
+	// copied to the plain server frame.
+	pm.data = frameData[len(frameData)-len(data):]
+	return pm, nil
+}
+
+func (pm *PreparedMessage) frame(key prepareKey) (int, []byte, error) {
+	pm.mu.Lock()
+	frame, ok := pm.frames[key]
+	if !ok {
+		frame = &preparedFrame{}
+		pm.frames[key] = frame
+	}
+	pm.mu.Unlock()
+
+	var err error
+	frame.once.Do(func() {
+		// Prepare a frame using a 'fake' connection.
+		// TODO: Refactor code in conn.go to allow more direct construction of
+		// the frame.
+		mu := make(chan struct{}, 1)
+		mu <- struct{}{}
+		var nc prepareConn
+		c := &Conn{
+			conn:                   &nc,
+			mu:                     mu,
+			isServer:               key.isServer,
+			compressionLevel:       key.compressionLevel,
+			enableWriteCompression: true,
+			writeBuf:               make([]byte, defaultWriteBufferSize+maxFrameHeaderSize),
+		}
+		if key.compress {
+			c.newCompressionWriter = compressNoContextTakeover
+		}
+		err = c.WriteMessage(pm.messageType, pm.data)
+		frame.data = nc.buf.Bytes()
+	})
+	return pm.messageType, frame.data, err
+}
+
+type prepareConn struct {
+	buf bytes.Buffer
+	net.Conn
+}
+
+func (pc *prepareConn) Write(p []byte) (int, error)        { return pc.buf.Write(p) }
+func (pc *prepareConn) SetWriteDeadline(t time.Time) error { return nil }
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+type netDialerFunc func(ctx context.Context, network, addr string) (net.Conn, error)
+
+func (fn netDialerFunc) Dial(network, addr string) (net.Conn, error) {
+	return fn(context.Background(), network, addr)
+}
+
+func (fn netDialerFunc) DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
+	return fn(ctx, network, addr)
+}
+
+func proxyFromURL(proxyURL *url.URL, forwardDial netDialerFunc) (netDialerFunc, error) {
+	if proxyURL.Scheme == "http" {
+		return (&httpProxyDialer{proxyURL: proxyURL, forwardDial: forwardDial}).DialContext, nil
+	}
+	dialer, err := proxy.FromURL(proxyURL, forwardDial)
+	if err != nil {
+		return nil, err
+	}
+	if d, ok := dialer.(proxy.ContextDialer); ok {
+		return d.DialContext, nil
+	}
+	return func(ctx context.Context, net, addr string) (net.Conn, error) {
+		return dialer.Dial(net, addr)
+	}, nil
+}
+
+type httpProxyDialer struct {
+	proxyURL    *url.URL
+	forwardDial netDialerFunc
+}
+
+func (hpd *httpProxyDialer) DialContext(ctx context.Context, network string, addr string) (net.Conn, error) {
+	hostPort, _ := hostPortNoPort(hpd.proxyURL)
+	conn, err := hpd.forwardDial(ctx, network, hostPort)
+	if err != nil {
+		return nil, err
+	}
+
+	connectHeader := make(http.Header)
+	if user := hpd.proxyURL.User; user != nil {
+		proxyUser := user.Username()
+		if proxyPassword, passwordSet := user.Password(); passwordSet {
+			credential := base64.StdEncoding.EncodeToString([]byte(proxyUser + ":" + proxyPassword))
+			connectHeader.Set("Proxy-Authorization", "Basic "+credential)
+		}
+	}
+
+	connectReq := &http.Request{
+		Method: http.MethodConnect,
+		URL:    &url.URL{Opaque: addr},
+		Host:   addr,
+		Header: connectHeader,
+	}
+
+	if err := connectReq.Write(conn); err != nil {
+		conn.Close()
+		return nil, err
+	}
+
+	// Read response. It's OK to use and discard buffered reader here because
+	// the remote server does not speak until spoken to.
+	br := bufio.NewReader(conn)
+	resp, err := http.ReadResponse(br, connectReq)
+	if err != nil {
+		conn.Close()
+		return nil, err
+	}
+
+	// Close the response body to silence false positives from linters. Reset
+	// the buffered reader first to ensure that Close() does not read from
+	// conn.
+	// Note: Applications must call resp.Body.Close() on a response returned
+	// http.ReadResponse to inspect trailers or read another response from the
+	// buffered reader. The call to resp.Body.Close() does not release
+	// resources.
+	br.Reset(bytes.NewReader(nil))
+	_ = resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		_ = conn.Close()
+		f := strings.SplitN(resp.Status, " ", 2)
+		return nil, errors.New(f[1])
+	}
+	return conn, nil
+}
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+// HandshakeError describes an error with the handshake from the peer.
+type HandshakeError struct {
+	message string
+}
+
+func (e HandshakeError) Error() string { return e.message }
+
+// Upgrader specifies parameters for upgrading an HTTP connection to a
+// WebSocket connection.
+//
+// It is safe to call Upgrader's methods concurrently.
+type Upgrader struct {
+	// HandshakeTimeout specifies the duration for the handshake to complete.
+	HandshakeTimeout time.Duration
+
+	// ReadBufferSize and WriteBufferSize specify I/O buffer sizes in bytes. If a buffer
+	// size is zero, then buffers allocated by the HTTP server are used. The
+	// I/O buffer sizes do not limit the size of the messages that can be sent
+	// or received.
+	ReadBufferSize, WriteBufferSize int
+
+	// WriteBufferPool is a pool of buffers for write operations. If the value
+	// is not set, then write buffers are allocated to the connection for the
+	// lifetime of the connection.
+	//
+	// A pool is most useful when the application has a modest volume of writes
+	// across a large number of connections.
+	//
+	// Applications should use a single pool for each unique value of
+	// WriteBufferSize.
+	WriteBufferPool BufferPool
+
+	// Subprotocols specifies the server's supported protocols in order of
+	// preference. If this field is not nil, then the Upgrade method negotiates a
+	// subprotocol by selecting the first match in this list with a protocol
+	// requested by the client. If there's no match, then no protocol is
+	// negotiated (the Sec-Websocket-Protocol header is not included in the
+	// handshake response).
+	Subprotocols []string
+
+	// Error specifies the function for generating HTTP error responses. If Error
+	// is nil, then http.Error is used to generate the HTTP response.
+	Error func(w http.ResponseWriter, r *http.Request, status int, reason error)
+
+	// CheckOrigin returns true if the request Origin header is acceptable. If
+	// CheckOrigin is nil, then a safe default is used: return false if the
+	// Origin request header is present and the origin host is not equal to
+	// request Host header.
+	//
+	// A CheckOrigin function should carefully validate the request origin to
+	// prevent cross-site request forgery.
+	CheckOrigin func(r *http.Request) bool
+
+	// EnableCompression specify if the server should attempt to negotiate per
+	// message compression (RFC 7692). Setting this value to true does not
+	// guarantee that compression will be supported. Currently only "no context
+	// takeover" modes are supported.
+	EnableCompression bool
+}
+
+func (u *Upgrader) returnError(w http.ResponseWriter, r *http.Request, status int, reason string) (*Conn, error) {
+	err := HandshakeError{reason}
+	if u.Error != nil {
+		u.Error(w, r, status, err)
+	} else {
+		w.Header().Set("Sec-Websocket-Version", "13")
+		http.Error(w, http.StatusText(status), status)
+	}
+	return nil, err
+}
+
+// checkSameOrigin returns true if the origin is not set or is equal to the request host.
+func checkSameOrigin(r *http.Request) bool {
+	origin := r.Header["Origin"]
+	if len(origin) == 0 {
+		return true
+	}
+	u, err := url.Parse(origin[0])
+	if err != nil {
+		return false
+	}
+	return equalASCIIFold(u.Host, r.Host)
+}
+
+func (u *Upgrader) selectSubprotocol(r *http.Request, responseHeader http.Header) string {
+	if u.Subprotocols != nil {
+		clientProtocols := Subprotocols(r)
+		for _, clientProtocol := range clientProtocols {
+			for _, serverProtocol := range u.Subprotocols {
+				if clientProtocol == serverProtocol {
+					return clientProtocol
+				}
+			}
+		}
+	} else if responseHeader != nil {
+		return responseHeader.Get("Sec-Websocket-Protocol")
+	}
+	return ""
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie). To specify
+// subprotocols supported by the server, set Upgrader.Subprotocols directly.
+//
+// If the upgrade fails, then Upgrade replies to the client with an HTTP error
+// response.
+func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header) (*Conn, error) {
+	const badHandshake = "websocket: the client is not using the websocket protocol: "
+
+	if !tokenListContainsValue(r.Header, "Connection", "upgrade") {
+		return u.returnError(w, r, http.StatusBadRequest, badHandshake+"'upgrade' token not found in 'Connection' header")
+	}
+
+	if !tokenListContainsValue(r.Header, "Upgrade", "websocket") {
+		w.Header().Set("Upgrade", "websocket")
+		return u.returnError(w, r, http.StatusUpgradeRequired, badHandshake+"'websocket' token not found in 'Upgrade' header")
+	}
+
+	if r.Method != http.MethodGet {
+		return u.returnError(w, r, http.StatusMethodNotAllowed, badHandshake+"request method is not GET")
+	}
+
+	if !tokenListContainsValue(r.Header, "Sec-Websocket-Version", "13") {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: unsupported version: 13 not found in 'Sec-Websocket-Version' header")
+	}
+
+	if _, ok := responseHeader["Sec-Websocket-Extensions"]; ok {
+		return u.returnError(w, r, http.StatusInternalServerError, "websocket: application specific 'Sec-WebSocket-Extensions' headers are unsupported")
+	}
+
+	checkOrigin := u.CheckOrigin
+	if checkOrigin == nil {
+		checkOrigin = checkSameOrigin
+	}
+	if !checkOrigin(r) {
+		return u.returnError(w, r, http.StatusForbidden, "websocket: request origin not allowed by Upgrader.CheckOrigin")
+	}
+
+	challengeKey := r.Header.Get("Sec-Websocket-Key")
+	if !isValidChallengeKey(challengeKey) {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: not a websocket handshake: 'Sec-WebSocket-Key' header must be Base64 encoded value of 16-byte in length")
+	}
+
+	subprotocol := u.selectSubprotocol(r, responseHeader)
+
+	// Negotiate PMCE
+	var compress bool
+	if u.EnableCompression {
+		for _, ext := range parseExtensions(r.Header) {
+			if ext[""] != "permessage-deflate" {
+				continue
+			}
+			compress = true
+			break
+		}
+	}
+
+	netConn, brw, err := http.NewResponseController(w).Hijack()
+	if err != nil {
+		return u.returnError(w, r, http.StatusInternalServerError,
+			"websocket: hijack: "+err.Error())
+	}
+
+	// Close the network connection when returning an error. The variable
+	// netConn is set to nil before the success return at the end of the
+	// function.
+	defer func() {
+		if netConn != nil {
+			// It's safe to ignore the error from Close() because this code is
+			// only executed when returning a more important error to the
+			// application.
+			_ = netConn.Close()
+		}
+	}()
+
+	var br *bufio.Reader
+	if u.ReadBufferSize == 0 && brw.Reader.Size() > 256 {
+		// Use hijacked buffered reader as the connection reader.
+		br = brw.Reader
+	} else if brw.Reader.Buffered() > 0 {
+		// Wrap the network connection to read buffered data in brw.Reader
+		// before reading from the network connection. This should be rare
+		// because a client must not send message data before receiving the
+		// handshake response.
+		netConn = &brNetConn{br: brw.Reader, Conn: netConn}
+	}
+
+	buf := brw.Writer.AvailableBuffer()
+
+	var writeBuf []byte
+	if u.WriteBufferPool == nil && u.WriteBufferSize == 0 && len(buf) >= maxFrameHeaderSize+256 {
+		// Reuse hijacked write buffer as connection buffer.
+		writeBuf = buf
+	}
+
+	c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize, u.WriteBufferPool, br, writeBuf)
+	c.subprotocol = subprotocol
+
+	if compress {
+		c.newCompressionWriter = compressNoContextTakeover
+		c.newDecompressionReader = decompressNoContextTakeover
+	}
+
+	// Use larger of hijacked buffer and connection write buffer for header.
+	p := buf
+	if len(c.writeBuf) > len(p) {
+		p = c.writeBuf
+	}
+	p = p[:0]
+
+	p = append(p, "HTTP/1.1 101 Switching Protocols\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Accept: "...)
+	p = append(p, computeAcceptKey(challengeKey)...)
+	p = append(p, "\r\n"...)
+	if c.subprotocol != "" {
+		p = append(p, "Sec-WebSocket-Protocol: "...)
+		p = append(p, c.subprotocol...)
+		p = append(p, "\r\n"...)
+	}
+	if compress {
+		p = append(p, "Sec-WebSocket-Extensions: permessage-deflate; server_no_context_takeover; client_no_context_takeover\r\n"...)
+	}
+	for k, vs := range responseHeader {
+		if k == "Sec-Websocket-Protocol" {
+			continue
+		}
+		for _, v := range vs {
+			p = append(p, k...)
+			p = append(p, ": "...)
+			for i := 0; i < len(v); i++ {
+				b := v[i]
+				if b <= 31 {
+					// prevent response splitting.
+					b = ' '
+				}
+				p = append(p, b)
+			}
+			p = append(p, "\r\n"...)
+		}
+	}
+	p = append(p, "\r\n"...)
+
+	if u.HandshakeTimeout > 0 {
+		if err := netConn.SetWriteDeadline(time.Now().Add(u.HandshakeTimeout)); err != nil {
+			return nil, err
+		}
+	} else {
+		// Clear deadlines set by HTTP server.
+		if err := netConn.SetDeadline(time.Time{}); err != nil {
+			return nil, err
+		}
+	}
+
+	if _, err = netConn.Write(p); err != nil {
+		return nil, err
+	}
+	if u.HandshakeTimeout > 0 {
+		if err := netConn.SetWriteDeadline(time.Time{}); err != nil {
+			return nil, err
+		}
+	}
+
+	// Success! Set netConn to nil to stop the deferred function above from
+	// closing the network connection.
+	netConn = nil
+
+	return c, nil
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// Deprecated: Use websocket.Upgrader instead.
+//
+// Upgrade does not perform origin checking. The application is responsible for
+// checking the Origin header before calling Upgrade. An example implementation
+// of the same origin policy check is:
+//
+//	if req.Header.Get("Origin") != "http://"+req.Host {
+//		http.Error(w, "Origin not allowed", http.StatusForbidden)
+//		return
+//	}
+//
+// If the endpoint supports subprotocols, then the application is responsible
+// for negotiating the protocol used on the connection. Use the Subprotocols()
+// function to get the subprotocols requested by the client. Use the
+// Sec-Websocket-Protocol response header to specify the subprotocol selected
+// by the application.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie) and the
+// negotiated subprotocol (Sec-Websocket-Protocol).
+//
+// The connection buffers IO to the underlying network connection. The
+// readBufSize and writeBufSize parameters specify the size of the buffers to
+// use. Messages can be larger than the buffers.
+//
+// If the request is not a valid WebSocket handshake, then Upgrade returns an
+// error of type HandshakeError. Applications should handle this error by
+// replying to the client with an HTTP error response.
+func Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header, readBufSize, writeBufSize int) (*Conn, error) {
+	u := Upgrader{ReadBufferSize: readBufSize, WriteBufferSize: writeBufSize}
+	u.Error = func(w http.ResponseWriter, r *http.Request, status int, reason error) {
+		// don't return errors to maintain backwards compatibility
+	}
+	u.CheckOrigin = func(r *http.Request) bool {
+		// allow all connections by default
+		return true
+	}
+	return u.Upgrade(w, r, responseHeader)
+}
+
+// Subprotocols returns the subprotocols requested by the client in the
+// Sec-Websocket-Protocol header.
+func Subprotocols(r *http.Request) []string {
+	h := strings.TrimSpace(r.Header.Get("Sec-Websocket-Protocol"))
+	if h == "" {
+		return nil
+	}
+	protocols := strings.Split(h, ",")
+	for i := range protocols {
+		protocols[i] = strings.TrimSpace(protocols[i])
+	}
+	return protocols
+}
+
+// IsWebSocketUpgrade returns true if the client requested upgrade to the
+// WebSocket protocol.
+func IsWebSocketUpgrade(r *http.Request) bool {
+	return tokenListContainsValue(r.Header, "Connection", "upgrade") &&
+		tokenListContainsValue(r.Header, "Upgrade", "websocket")
+}
+
+type brNetConn struct {
+	br *bufio.Reader
+	net.Conn
+}
+
+func (b *brNetConn) Read(p []byte) (n int, err error) {
+	if b.br != nil {
+		// Limit read to buferred data.
+		if n := b.br.Buffered(); len(p) > n {
+			p = p[:n]
+		}
+		n, err = b.br.Read(p)
+		if b.br.Buffered() == 0 {
+			b.br = nil
+		}
+		return n, err
+	}
+	return b.Conn.Read(p)
+}
+
+// NetConn returns the underlying connection that is wrapped by b.
+func (b *brNetConn) NetConn() net.Conn {
+	return b.Conn
+}
+
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+var keyGUID = []byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
+
+func computeAcceptKey(challengeKey string) string {
+	h := sha1.New()
+	h.Write([]byte(challengeKey))
+	h.Write(keyGUID)
+	return base64.StdEncoding.EncodeToString(h.Sum(nil))
+}
+
+func generateChallengeKey() (string, error) {
+	p := make([]byte, 16)
+	if _, err := io.ReadFull(rand.Reader, p); err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(p), nil
+}
+
+// Token octets per RFC 2616.
+var isTokenOctet = [256]bool{
+	'!':  true,
+	'#':  true,
+	'$':  true,
+	'%':  true,
+	'&':  true,
+	'\'': true,
+	'*':  true,
+	'+':  true,
+	'-':  true,
+	'.':  true,
+	'0':  true,
+	'1':  true,
+	'2':  true,
+	'3':  true,
+	'4':  true,
+	'5':  true,
+	'6':  true,
+	'7':  true,
+	'8':  true,
+	'9':  true,
+	'A':  true,
+	'B':  true,
+	'C':  true,
+	'D':  true,
+	'E':  true,
+	'F':  true,
+	'G':  true,
+	'H':  true,
+	'I':  true,
+	'J':  true,
+	'K':  true,
+	'L':  true,
+	'M':  true,
+	'N':  true,
+	'O':  true,
+	'P':  true,
+	'Q':  true,
+	'R':  true,
+	'S':  true,
+	'T':  true,
+	'U':  true,
+	'W':  true,
+	'V':  true,
+	'X':  true,
+	'Y':  true,
+	'Z':  true,
+	'^':  true,
+	'_':  true,
+	'`':  true,
+	'a':  true,
+	'b':  true,
+	'c':  true,
+	'd':  true,
+	'e':  true,
+	'f':  true,
+	'g':  true,
+	'h':  true,
+	'i':  true,
+	'j':  true,
+	'k':  true,
+	'l':  true,
+	'm':  true,
+	'n':  true,
+	'o':  true,
+	'p':  true,
+	'q':  true,
+	'r':  true,
+	's':  true,
+	't':  true,
+	'u':  true,
+	'v':  true,
+	'w':  true,
+	'x':  true,
+	'y':  true,
+	'z':  true,
+	'|':  true,
+	'~':  true,
+}
+
+// skipSpace returns a slice of the string s with all leading RFC 2616 linear
+// whitespace removed.
+func skipSpace(s string) (rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if b := s[i]; b != ' ' && b != '\t' {
+			break
+		}
+	}
+	return s[i:]
+}
+
+// nextToken returns the leading RFC 2616 token of s and the string following
+// the token.
+func nextToken(s string) (token, rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if !isTokenOctet[s[i]] {
+			break
+		}
+	}
+	return s[:i], s[i:]
+}
+
+// nextTokenOrQuoted returns the leading token or quoted string per RFC 2616
+// and the string following the token or quoted string.
+func nextTokenOrQuoted(s string) (value string, rest string) {
+	if !strings.HasPrefix(s, "\"") {
+		return nextToken(s)
+	}
+	s = s[1:]
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '"':
+			return s[:i], s[i+1:]
+		case '\\':
+			p := make([]byte, len(s)-1)
+			j := copy(p, s[:i])
+			escape := true
+			for i = i + 1; i < len(s); i++ {
+				b := s[i]
+				switch {
+				case escape:
+					escape = false
+					p[j] = b
+					j++
+				case b == '\\':
+					escape = true
+				case b == '"':
+					return string(p[:j]), s[i+1:]
+				default:
+					p[j] = b
+					j++
+				}
+			}
+			return "", ""
+		}
+	}
+	return "", ""
+}
+
+// equalASCIIFold returns true if s is equal to t with ASCII case folding as
+// defined in RFC 4790.
+func equalASCIIFold(s, t string) bool {
+	for s != "" && t != "" {
+		sr, size := utf8.DecodeRuneInString(s)
+		s = s[size:]
+		tr, size := utf8.DecodeRuneInString(t)
+		t = t[size:]
+		if sr == tr {
+			continue
+		}
+		if 'A' <= sr && sr <= 'Z' {
+			sr = sr + 'a' - 'A'
+		}
+		if 'A' <= tr && tr <= 'Z' {
+			tr = tr + 'a' - 'A'
+		}
+		if sr != tr {
+			return false
+		}
+	}
+	return s == t
+}
+
+// tokenListContainsValue returns true if the 1#token header with the given
+// name contains a token equal to value with ASCII case folding.
+func tokenListContainsValue(header http.Header, name string, value string) bool {
+headers:
+	for _, s := range header[name] {
+		for {
+			var t string
+			t, s = nextToken(skipSpace(s))
+			if t == "" {
+				continue headers
+			}
+			s = skipSpace(s)
+			if s != "" && s[0] != ',' {
+				continue headers
+			}
+			if equalASCIIFold(t, value) {
+				return true
+			}
+			if s == "" {
+				continue headers
+			}
+			s = s[1:]
+		}
+	}
+	return false
+}
+
+// parseExtensions parses WebSocket extensions from a header.
+func parseExtensions(header http.Header) []map[string]string {
+	// From RFC 6455:
+	//
+	//  Sec-WebSocket-Extensions = extension-list
+	//  extension-list = 1#extension
+	//  extension = extension-token *( ";" extension-param )
+	//  extension-token = registered-token
+	//  registered-token = token
+	//  extension-param = token [ "=" (token | quoted-string) ]
+	//     ;When using the quoted-string syntax variant, the value
+	//     ;after quoted-string unescaping MUST conform to the
+	//     ;'token' ABNF.
+
+	var result []map[string]string
+headers:
+	for _, s := range header["Sec-Websocket-Extensions"] {
+		for {
+			var t string
+			t, s = nextToken(skipSpace(s))
+			if t == "" {
+				continue headers
+			}
+			ext := map[string]string{"": t}
+			for {
+				s = skipSpace(s)
+				if !strings.HasPrefix(s, ";") {
+					break
+				}
+				var k string
+				k, s = nextToken(skipSpace(s[1:]))
+				if k == "" {
+					continue headers
+				}
+				s = skipSpace(s)
+				var v string
+				if strings.HasPrefix(s, "=") {
+					v, s = nextTokenOrQuoted(skipSpace(s[1:]))
+					s = skipSpace(s)
+				}
+				if s != "" && s[0] != ',' && s[0] != ';' {
+					continue headers
+				}
+				ext[k] = v
+			}
+			if s != "" && s[0] != ',' {
+				continue headers
+			}
+			result = append(result, ext)
+			if s == "" {
+				continue headers
+			}
+			s = s[1:]
+		}
+	}
+	return result
+}
+
+// isValidChallengeKey checks if the argument meets RFC6455 specification.
+func isValidChallengeKey(s string) bool {
+	// From RFC6455:
+	//
+	// A |Sec-WebSocket-Key| header field with a base64-encoded (see
+	// Section 4 of [RFC4648]) value that, when decoded, is 16 bytes in
+	// length.
+
+	if s == "" {
+		return false
+	}
+	decoded, err := base64.StdEncoding.DecodeString(s)
+	return err == nil && len(decoded) == 16
+}
+
+type CLIArgs struct {
+	FromAddr string
+	ToAddr   string
+}
+
+
+
+const X = 1
+
+var EmitActiveConnection = g.MakeGauge("active-connections")
+
+
+
+func ParseArgs(args []string) CLIArgs {
+	if len(args) != 3 {
+		fmt.Fprintf(
+			os.Stderr,
+			"Usage: %s FROM.socket TO.socket\n",
+			args[0],
+		)
+		os.Exit(2)
+	}
+	return CLIArgs {
+		FromAddr: args[1],
+		ToAddr:   args[2],
+	}
+}
+
+func Listen(fromAddr string) net.Listener {
+	listener, err := net.Listen("unix", fromAddr)
+	g.FatalIf(err)
+	g.Info("Started listening", "listen-start", "from-address", fromAddr)
+	return listener
+}
+
+func copyData(c chan struct {}, from io.Reader, to io.WriteCloser) {
+	io.Copy(to, from)
+	c <- struct {} {}
+}
+
+func Start(toAddr string, listener net.Listener) {
+	/*
+	upgrader := websocket.Upgrader {}
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		connFrom, err := upgrader.Upgrade(w, r, nil)
+		if err != nil {
+			g.Warning(
+				"Error upgrading connection",
+				"upgrade-connection-error",
+				"err", err,
+			)
+			return
+		}
+		defer connFrom.Close()
+		EmitActiveConnection.Inc()
+
+		connTo, err := net.Dial("unix", toAddr)
+		if err != nil {
+			g.Error(
+				"Error dialing connection",
+				"dial-connection",
+				"err", err,
+			)
+			os.Exit(1)
+		}
+		defer connTo.Close()
+
+		messageType, reader, err := connFrom.NextReader()
+		if err != nil {
+			g.Warning(
+				"Failed to get next reader from connection",
+				"connection-next-reader-error",
+				"err", err,
+			)
+			return
+		}
+
+		writer, err := connFrom.NextWriter(messageType)
+		if err != nil {
+			g.Warning(
+				"Failed to get next reader from connection",
+				"connection-next-reader-error",
+				"err", err,
+			)
+			return
+		}
+
+
+		c := make(chan struct {})
+		go copyData(c, connTo, writer)
+		go copyData(c, reader, connTo)
+		go func() {
+			<- c
+			EmitActiveConnection.Dec()
+		}()
+	});
+
+	server := http.Server{}
+	err := server.Serve(listener)
+	g.FatalIf(err)
+	*/
+}
+
+
+func Main() {
+	g.Init()
+	args := ParseArgs(os.Args)
+	listener := Listen(args.FromAddr)
+	Start(args.ToAddr, listener)
+}
diff --git a/tests/lib_test.go b/tests/lib_test.go
deleted file mode 100644
index 1007609..0000000
--- a/tests/lib_test.go
+++ /dev/null
@@ -1,24 +0,0 @@
-package wscat_test
-
-import (
-	"testing"
-
-	g "euandre.org/gobang/src"
-
-	"euandre.org/wscat/src"
-)
-
-
-func TestPlaceholder(t *testing.T) {
-	g.AssertEqual(t, wscat.X, 1)
-}
-
-func TestParseArgs(t *testing.T) {
-	given := wscat.ParseArgs([]string { "x", "y", "z" })
-	expected := wscat.CLIArgs {
-		FromAddr: "y",
-		ToAddr:   "z",
-	}
-
-	g.AssertEqual(t, given, expected)
-}
diff --git a/tests/main.go b/tests/main.go
new file mode 100644
index 0000000..8123486
--- /dev/null
+++ b/tests/main.go
@@ -0,0 +1,7 @@
+package main
+
+import "wscat"
+
+func main() {
+	wscat.MainTest()
+}
diff --git a/tests/wscat.go b/tests/wscat.go
new file mode 100644
index 0000000..da16f66
--- /dev/null
+++ b/tests/wscat.go
@@ -0,0 +1,2842 @@
+package wscat
+
+import (
+	"bufio"
+	"bytes"
+	"compress/flate"
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/binary"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"math/rand"
+	"net"
+	"net/http"
+	"net/http/cookiejar"
+	"net/http/httptest"
+	"net/http/httptrace"
+	"net/url"
+	"os"
+	"reflect"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"testing/internal/testdeps"
+	"testing/iotest"
+	"time"
+
+	g "gobang"
+)
+
+
+
+var cstUpgrader = Upgrader{
+	Subprotocols:      []string{"p0", "p1"},
+	ReadBufferSize:    1024,
+	WriteBufferSize:   1024,
+	EnableCompression: true,
+	Error: func(w http.ResponseWriter, r *http.Request, status int, reason error) {
+		http.Error(w, reason.Error(), status)
+	},
+}
+
+var cstDialer = Dialer{
+	Subprotocols:     []string{"p1", "p2"},
+	ReadBufferSize:   1024,
+	WriteBufferSize:  1024,
+	HandshakeTimeout: 30 * time.Second,
+}
+
+type cstHandler struct {
+	*testing.T
+	s *cstServer
+}
+
+type cstServer struct {
+	URL    string
+	Server *httptest.Server
+	wg     sync.WaitGroup
+}
+
+const (
+	cstPath       = "/a/b"
+	cstRawQuery   = "x=y"
+	cstRequestURI = cstPath + "?" + cstRawQuery
+)
+
+func (s *cstServer) Close() {
+	s.Server.Close()
+	// Wait for handler functions to complete.
+	s.wg.Wait()
+}
+
+func newServer(t *testing.T) *cstServer {
+	var s cstServer
+	s.Server = httptest.NewServer(cstHandler{T: t, s: &s})
+	s.Server.URL += cstRequestURI
+	s.URL = makeWsProto(s.Server.URL)
+	return &s
+}
+
+func newTLSServer(t *testing.T) *cstServer {
+	var s cstServer
+	s.Server = httptest.NewTLSServer(cstHandler{T: t, s: &s})
+	s.Server.URL += cstRequestURI
+	s.URL = makeWsProto(s.Server.URL)
+	return &s
+}
+
+func (t cstHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	// Because tests wait for a response from a server, we are guaranteed that
+	// the wait group count is incremented before the test waits on the group
+	// in the call to (*cstServer).Close().
+	t.s.wg.Add(1)
+	defer t.s.wg.Done()
+
+	if r.URL.Path != cstPath {
+		t.Logf("path=%v, want %v", r.URL.Path, cstPath)
+		http.Error(w, "bad path", http.StatusBadRequest)
+		return
+	}
+	if r.URL.RawQuery != cstRawQuery {
+		t.Logf("query=%v, want %v", r.URL.RawQuery, cstRawQuery)
+		http.Error(w, "bad path", http.StatusBadRequest)
+		return
+	}
+	subprotos := Subprotocols(r)
+	if !reflect.DeepEqual(subprotos, cstDialer.Subprotocols) {
+		t.Logf("subprotols=%v, want %v", subprotos, cstDialer.Subprotocols)
+		http.Error(w, "bad protocol", http.StatusBadRequest)
+		return
+	}
+	ws, err := cstUpgrader.Upgrade(w, r, http.Header{"Set-Cookie": {"sessionID=1234"}})
+	if err != nil {
+		t.Logf("Upgrade: %v", err)
+		return
+	}
+	defer ws.Close()
+
+	if ws.Subprotocol() != "p1" {
+		t.Logf("Subprotocol() = %s, want p1", ws.Subprotocol())
+		ws.Close()
+		return
+	}
+	op, rd, err := ws.NextReader()
+	if err != nil {
+		t.Logf("NextReader: %v", err)
+		return
+	}
+	wr, err := ws.NextWriter(op)
+	if err != nil {
+		t.Logf("NextWriter: %v", err)
+		return
+	}
+	if _, err = io.Copy(wr, rd); err != nil {
+		t.Logf("NextWriter: %v", err)
+		return
+	}
+	if err := wr.Close(); err != nil {
+		t.Logf("Close: %v", err)
+		return
+	}
+}
+
+func makeWsProto(s string) string {
+	return "ws" + strings.TrimPrefix(s, "http")
+}
+
+func sendRecv(t *testing.T, ws *Conn) {
+	const message = "Hello World!"
+	if err := ws.SetWriteDeadline(time.Now().Add(time.Second)); err != nil {
+		t.Fatalf("SetWriteDeadline: %v", err)
+	}
+	if err := ws.WriteMessage(TextMessage, []byte(message)); err != nil {
+		t.Fatalf("WriteMessage: %v", err)
+	}
+	if err := ws.SetReadDeadline(time.Now().Add(time.Second)); err != nil {
+		t.Fatalf("SetReadDeadline: %v", err)
+	}
+	_, p, err := ws.ReadMessage()
+	if err != nil {
+		t.Fatalf("ReadMessage: %v", err)
+	}
+	if string(p) != message {
+		t.Fatalf("message=%s, want %s", p, message)
+	}
+}
+
+func TestProxyDial(t *testing.T) {
+
+	s := newServer(t)
+	defer s.Close()
+
+	surl, _ := url.Parse(s.Server.URL)
+
+	cstDialer := cstDialer // make local copy for modification on next line.
+	cstDialer.Proxy = http.ProxyURL(surl)
+
+	connect := false
+	origHandler := s.Server.Config.Handler
+
+	// Capture the request Host header.
+	s.Server.Config.Handler = http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			if r.Method == http.MethodConnect {
+				connect = true
+				w.WriteHeader(http.StatusOK)
+				return
+			}
+
+			if !connect {
+				t.Log("connect not received")
+				http.Error(w, "connect not received", http.StatusMethodNotAllowed)
+				return
+			}
+			origHandler.ServeHTTP(w, r)
+		})
+
+	ws, _, err := cstDialer.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+func TestProxyAuthorizationDial(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	surl, _ := url.Parse(s.Server.URL)
+	surl.User = url.UserPassword("username", "password")
+
+	cstDialer := cstDialer // make local copy for modification on next line.
+	cstDialer.Proxy = http.ProxyURL(surl)
+
+	connect := false
+	origHandler := s.Server.Config.Handler
+
+	// Capture the request Host header.
+	s.Server.Config.Handler = http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			proxyAuth := r.Header.Get("Proxy-Authorization")
+			expectedProxyAuth := "Basic " + base64.StdEncoding.EncodeToString([]byte("username:password"))
+			if r.Method == http.MethodConnect && proxyAuth == expectedProxyAuth {
+				connect = true
+				w.WriteHeader(http.StatusOK)
+				return
+			}
+
+			if !connect {
+				t.Log("connect with proxy authorization not received")
+				http.Error(w, "connect with proxy authorization not received", http.StatusMethodNotAllowed)
+				return
+			}
+			origHandler.ServeHTTP(w, r)
+		})
+
+	ws, _, err := cstDialer.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+func TestDial(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	ws, _, err := cstDialer.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+func TestDialCookieJar(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	jar, _ := cookiejar.New(nil)
+	d := cstDialer
+	d.Jar = jar
+
+	u, _ := url.Parse(s.URL)
+
+	switch u.Scheme {
+	case "ws":
+		u.Scheme = "http"
+	case "wss":
+		u.Scheme = "https"
+	}
+
+	cookies := []*http.Cookie{{Name: "gorilla", Value: "ws", Path: "/"}}
+	d.Jar.SetCookies(u, cookies)
+
+	ws, _, err := d.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+
+	var gorilla string
+	var sessionID string
+	for _, c := range d.Jar.Cookies(u) {
+		if c.Name == "gorilla" {
+			gorilla = c.Value
+		}
+
+		if c.Name == "sessionID" {
+			sessionID = c.Value
+		}
+	}
+	if gorilla != "ws" {
+		t.Error("Cookie not present in jar.")
+	}
+
+	if sessionID != "1234" {
+		t.Error("Set-Cookie not received from the server.")
+	}
+
+	sendRecv(t, ws)
+}
+
+func rootCAs(t *testing.T, s *httptest.Server) *x509.CertPool {
+	certs := x509.NewCertPool()
+	for _, c := range s.TLS.Certificates {
+		roots, err := x509.ParseCertificates(c.Certificate[len(c.Certificate)-1])
+		if err != nil {
+			t.Fatalf("error parsing server's root cert: %v", err)
+		}
+		for _, root := range roots {
+			certs.AddCert(root)
+		}
+	}
+	return certs
+}
+
+func TestDialTLS(t *testing.T) {
+	s := newTLSServer(t)
+	defer s.Close()
+
+	d := cstDialer
+	d.TLSClientConfig = &tls.Config{RootCAs: rootCAs(t, s.Server)}
+	ws, _, err := d.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+func TestDialTimeout(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	d := cstDialer
+	d.HandshakeTimeout = -1
+	ws, _, err := d.Dial(s.URL, nil)
+	if err == nil {
+		ws.Close()
+		t.Fatalf("Dial: nil")
+	}
+}
+
+// requireDeadlineNetConn fails the current test when Read or Write are called
+// with no deadline.
+type requireDeadlineNetConn struct {
+	t                  *testing.T
+	c                  net.Conn
+	readDeadlineIsSet  bool
+	writeDeadlineIsSet bool
+}
+
+func (c *requireDeadlineNetConn) SetDeadline(t time.Time) error {
+	c.writeDeadlineIsSet = !t.Equal(time.Time{})
+	c.readDeadlineIsSet = c.writeDeadlineIsSet
+	return c.c.SetDeadline(t)
+}
+
+func (c *requireDeadlineNetConn) SetReadDeadline(t time.Time) error {
+	c.readDeadlineIsSet = !t.Equal(time.Time{})
+	return c.c.SetDeadline(t)
+}
+
+func (c *requireDeadlineNetConn) SetWriteDeadline(t time.Time) error {
+	c.writeDeadlineIsSet = !t.Equal(time.Time{})
+	return c.c.SetDeadline(t)
+}
+
+func (c *requireDeadlineNetConn) Write(p []byte) (int, error) {
+	if !c.writeDeadlineIsSet {
+		c.t.Fatalf("write with no deadline")
+	}
+	return c.c.Write(p)
+}
+
+func (c *requireDeadlineNetConn) Read(p []byte) (int, error) {
+	if !c.readDeadlineIsSet {
+		c.t.Fatalf("read with no deadline")
+	}
+	return c.c.Read(p)
+}
+
+func (c *requireDeadlineNetConn) Close() error         { return c.c.Close() }
+func (c *requireDeadlineNetConn) LocalAddr() net.Addr  { return c.c.LocalAddr() }
+func (c *requireDeadlineNetConn) RemoteAddr() net.Addr { return c.c.RemoteAddr() }
+
+func TestHandshakeTimeout(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	d := cstDialer
+	d.NetDial = func(n, a string) (net.Conn, error) {
+		c, err := net.Dial(n, a)
+		return &requireDeadlineNetConn{c: c, t: t}, err
+	}
+	ws, _, err := d.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatal("Dial:", err)
+	}
+	ws.Close()
+}
+
+func TestHandshakeTimeoutInContext(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	d := cstDialer
+	d.HandshakeTimeout = 0
+	d.NetDialContext = func(ctx context.Context, n, a string) (net.Conn, error) {
+		netDialer := &net.Dialer{}
+		c, err := netDialer.DialContext(ctx, n, a)
+		return &requireDeadlineNetConn{c: c, t: t}, err
+	}
+
+	ctx, cancel := context.WithDeadline(context.Background(), time.Now().Add(30*time.Second))
+	defer cancel()
+	ws, _, err := d.DialContext(ctx, s.URL, nil)
+	if err != nil {
+		t.Fatal("Dial:", err)
+	}
+	ws.Close()
+}
+
+func TestDialBadScheme(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	ws, _, err := cstDialer.Dial(s.Server.URL, nil)
+	if err == nil {
+		ws.Close()
+		t.Fatalf("Dial: nil")
+	}
+}
+
+func TestDialBadOrigin(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	ws, resp, err := cstDialer.Dial(s.URL, http.Header{"Origin": {"bad"}})
+	if err == nil {
+		ws.Close()
+		t.Fatalf("Dial: nil")
+	}
+	if resp == nil {
+		t.Fatalf("resp=nil, err=%v", err)
+	}
+	if resp.StatusCode != http.StatusForbidden {
+		t.Fatalf("status=%d, want %d", resp.StatusCode, http.StatusForbidden)
+	}
+}
+
+func TestDialBadHeader(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	for _, k := range []string{"Upgrade",
+		"Connection",
+		"Sec-Websocket-Key",
+		"Sec-Websocket-Version",
+		"Sec-Websocket-Protocol"} {
+		h := http.Header{}
+		h.Set(k, "bad")
+		ws, _, err := cstDialer.Dial(s.URL, http.Header{"Origin": {"bad"}})
+		if err == nil {
+			ws.Close()
+			t.Errorf("Dial with header %s returned nil", k)
+		}
+	}
+}
+
+func TestBadMethod(t *testing.T) {
+	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ws, err := cstUpgrader.Upgrade(w, r, nil)
+		if err == nil {
+			t.Errorf("handshake succeeded, expect fail")
+			ws.Close()
+		}
+	}))
+	defer s.Close()
+
+	req, err := http.NewRequest(http.MethodPost, s.URL, strings.NewReader(""))
+	if err != nil {
+		t.Fatalf("NewRequest returned error %v", err)
+	}
+	req.Header.Set("Connection", "upgrade")
+	req.Header.Set("Upgrade", "websocket")
+	req.Header.Set("Sec-Websocket-Version", "13")
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("Do returned error %v", err)
+	}
+	resp.Body.Close()
+	if resp.StatusCode != http.StatusMethodNotAllowed {
+		t.Errorf("Status = %d, want %d", resp.StatusCode, http.StatusMethodNotAllowed)
+	}
+}
+
+func TestNoUpgrade(t *testing.T) {
+	t.Parallel()
+	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ws, err := cstUpgrader.Upgrade(w, r, nil)
+		if err == nil {
+			t.Errorf("handshake succeeded, expect fail")
+			ws.Close()
+		}
+	}))
+	defer s.Close()
+
+	req, err := http.NewRequest(http.MethodGet, s.URL, strings.NewReader(""))
+	if err != nil {
+		t.Fatalf("NewRequest returned error %v", err)
+	}
+	req.Header.Set("Connection", "upgrade")
+	req.Header.Set("Sec-Websocket-Version", "13")
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("Do returned error %v", err)
+	}
+	resp.Body.Close()
+	if u := resp.Header.Get("Upgrade"); u != "websocket" {
+		t.Errorf("Upgrade response header is %q, want %q", u, "websocket")
+	}
+	if resp.StatusCode != http.StatusUpgradeRequired {
+		t.Errorf("Status = %d, want %d", resp.StatusCode, http.StatusUpgradeRequired)
+	}
+}
+
+func TestDialExtraTokensInRespHeaders(t *testing.T) {
+	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		challengeKey := r.Header.Get("Sec-Websocket-Key")
+		w.Header().Set("Upgrade", "foo, websocket")
+		w.Header().Set("Connection", "upgrade, keep-alive")
+		w.Header().Set("Sec-Websocket-Accept", computeAcceptKey(challengeKey))
+		w.WriteHeader(101)
+	}))
+	defer s.Close()
+
+	ws, _, err := cstDialer.Dial(makeWsProto(s.URL), nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+}
+
+func TestHandshake(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	ws, resp, err := cstDialer.Dial(s.URL, http.Header{"Origin": {s.URL}})
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+
+	var sessionID string
+	for _, c := range resp.Cookies() {
+		if c.Name == "sessionID" {
+			sessionID = c.Value
+		}
+	}
+	if sessionID != "1234" {
+		t.Error("Set-Cookie not received from the server.")
+	}
+
+	if ws.Subprotocol() != "p1" {
+		t.Errorf("ws.Subprotocol() = %s, want p1", ws.Subprotocol())
+	}
+	sendRecv(t, ws)
+}
+
+func TestRespOnBadHandshake(t *testing.T) {
+	const expectedStatus = http.StatusGone
+	const expectedBody = "This is the response body."
+
+	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(expectedStatus)
+		_, _ = io.WriteString(w, expectedBody)
+	}))
+	defer s.Close()
+
+	ws, resp, err := cstDialer.Dial(makeWsProto(s.URL), nil)
+	if err == nil {
+		ws.Close()
+		t.Fatalf("Dial: nil")
+	}
+
+	if resp == nil {
+		t.Fatalf("resp=nil, err=%v", err)
+	}
+
+	if resp.StatusCode != expectedStatus {
+		t.Errorf("resp.StatusCode=%d, want %d", resp.StatusCode, expectedStatus)
+	}
+
+	p, err := io.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatalf("ReadFull(resp.Body) returned error %v", err)
+	}
+
+	if string(p) != expectedBody {
+		t.Errorf("resp.Body=%s, want %s", p, expectedBody)
+	}
+}
+
+type testLogWriter struct {
+	t *testing.T
+}
+
+func (w testLogWriter) Write(p []byte) (int, error) {
+	w.t.Logf("%s", p)
+	return len(p), nil
+}
+
+// TestHost tests handling of host names and confirms that it matches net/http.
+func TestHost(t *testing.T) {
+
+	upgrader := Upgrader{}
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if IsWebSocketUpgrade(r) {
+			c, err := upgrader.Upgrade(w, r, http.Header{"X-Test-Host": {r.Host}})
+			if err != nil {
+				t.Fatal(err)
+			}
+			c.Close()
+		} else {
+			w.Header().Set("X-Test-Host", r.Host)
+		}
+	})
+
+	server := httptest.NewServer(handler)
+	defer server.Close()
+
+	tlsServer := httptest.NewTLSServer(handler)
+	defer tlsServer.Close()
+
+	addrs := map[*httptest.Server]string{server: server.Listener.Addr().String(), tlsServer: tlsServer.Listener.Addr().String()}
+	wsProtos := map[*httptest.Server]string{server: "ws://", tlsServer: "wss://"}
+	httpProtos := map[*httptest.Server]string{server: "http://", tlsServer: "https://"}
+
+	// Avoid log noise from net/http server by logging to testing.T
+	server.Config.ErrorLog = log.New(testLogWriter{t}, "", 0)
+	tlsServer.Config.ErrorLog = server.Config.ErrorLog
+
+	cas := rootCAs(t, tlsServer)
+
+	tests := []struct {
+		fail               bool             // true if dial / get should fail
+		server             *httptest.Server // server to use
+		url                string           // host for request URI
+		header             string           // optional request host header
+		tls                string           // optional host for tls ServerName
+		wantAddr           string           // expected host for dial
+		wantHeader         string           // expected request header on server
+		insecureSkipVerify bool
+	}{
+		{
+			server:     server,
+			url:        addrs[server],
+			wantAddr:   addrs[server],
+			wantHeader: addrs[server],
+		},
+		{
+			server:     tlsServer,
+			url:        addrs[tlsServer],
+			wantAddr:   addrs[tlsServer],
+			wantHeader: addrs[tlsServer],
+		},
+
+		{
+			server:     server,
+			url:        addrs[server],
+			header:     "badhost.com",
+			wantAddr:   addrs[server],
+			wantHeader: "badhost.com",
+		},
+		{
+			server:     tlsServer,
+			url:        addrs[tlsServer],
+			header:     "badhost.com",
+			wantAddr:   addrs[tlsServer],
+			wantHeader: "badhost.com",
+		},
+
+		{
+			server:     server,
+			url:        "example.com",
+			header:     "badhost.com",
+			wantAddr:   "example.com:80",
+			wantHeader: "badhost.com",
+		},
+		{
+			server:     tlsServer,
+			url:        "example.com",
+			header:     "badhost.com",
+			wantAddr:   "example.com:443",
+			wantHeader: "badhost.com",
+		},
+
+		{
+			server:     server,
+			url:        "badhost.com",
+			header:     "example.com",
+			wantAddr:   "badhost.com:80",
+			wantHeader: "example.com",
+		},
+		{
+			fail:     true,
+			server:   tlsServer,
+			url:      "badhost.com",
+			header:   "example.com",
+			wantAddr: "badhost.com:443",
+		},
+		{
+			server:             tlsServer,
+			url:                "badhost.com",
+			insecureSkipVerify: true,
+			wantAddr:           "badhost.com:443",
+			wantHeader:         "badhost.com",
+		},
+		{
+			server:     tlsServer,
+			url:        "badhost.com",
+			tls:        "example.com",
+			wantAddr:   "badhost.com:443",
+			wantHeader: "badhost.com",
+		},
+	}
+
+	for i, tt := range tests {
+
+		tls := &tls.Config{
+			RootCAs:            cas,
+			ServerName:         tt.tls,
+			InsecureSkipVerify: tt.insecureSkipVerify,
+		}
+
+		var gotAddr string
+		dialer := Dialer{
+			NetDial: func(network, addr string) (net.Conn, error) {
+				gotAddr = addr
+				return net.Dial(network, addrs[tt.server])
+			},
+			TLSClientConfig: tls,
+		}
+
+		// Test websocket dial
+
+		h := http.Header{}
+		if tt.header != "" {
+			h.Set("Host", tt.header)
+		}
+		c, resp, err := dialer.Dial(wsProtos[tt.server]+tt.url+"/", h)
+		if err == nil {
+			c.Close()
+		}
+
+		check := func(protos map[*httptest.Server]string) {
+			name := fmt.Sprintf("%d: %s%s/ header[Host]=%q, tls.ServerName=%q", i+1, protos[tt.server], tt.url, tt.header, tt.tls)
+			if gotAddr != tt.wantAddr {
+				t.Errorf("%s: got addr %s, want %s", name, gotAddr, tt.wantAddr)
+			}
+			switch {
+			case tt.fail && err == nil:
+				t.Errorf("%s: unexpected success", name)
+			case !tt.fail && err != nil:
+				t.Errorf("%s: unexpected error %v", name, err)
+			case !tt.fail && err == nil:
+				if gotHost := resp.Header.Get("X-Test-Host"); gotHost != tt.wantHeader {
+					t.Errorf("%s: got host %s, want %s", name, gotHost, tt.wantHeader)
+				}
+			}
+		}
+
+		check(wsProtos)
+
+		// Confirm that net/http has same result
+
+		transport := &http.Transport{
+			Dial:            dialer.NetDial,
+			TLSClientConfig: dialer.TLSClientConfig,
+		}
+		req, _ := http.NewRequest(http.MethodGet, httpProtos[tt.server]+tt.url+"/", nil)
+		if tt.header != "" {
+			req.Host = tt.header
+		}
+		client := &http.Client{Transport: transport}
+		resp, err = client.Do(req)
+		if err == nil {
+			resp.Body.Close()
+		}
+		transport.CloseIdleConnections()
+		check(httpProtos)
+	}
+}
+
+func TestDialCompression(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	dialer := cstDialer
+	dialer.EnableCompression = true
+	ws, _, err := dialer.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+func TestSocksProxyDial(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	proxyListener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("listen failed: %v", err)
+	}
+	defer proxyListener.Close()
+	go func() {
+		c1, err := proxyListener.Accept()
+		if err != nil {
+			t.Errorf("proxy accept failed: %v", err)
+			return
+		}
+		defer c1.Close()
+
+		_ = c1.SetDeadline(time.Now().Add(30 * time.Second))
+
+		buf := make([]byte, 32)
+		if _, err := io.ReadFull(c1, buf[:3]); err != nil {
+			t.Errorf("read failed: %v", err)
+			return
+		}
+		if want := []byte{5, 1, 0}; !bytes.Equal(want, buf[:len(want)]) {
+			t.Errorf("read %x, want %x", buf[:len(want)], want)
+		}
+		if _, err := c1.Write([]byte{5, 0}); err != nil {
+			t.Errorf("write failed: %v", err)
+			return
+		}
+		if _, err := io.ReadFull(c1, buf[:10]); err != nil {
+			t.Errorf("read failed: %v", err)
+			return
+		}
+		if want := []byte{5, 1, 0, 1}; !bytes.Equal(want, buf[:len(want)]) {
+			t.Errorf("read %x, want %x", buf[:len(want)], want)
+			return
+		}
+		buf[1] = 0
+		if _, err := c1.Write(buf[:10]); err != nil {
+			t.Errorf("write failed: %v", err)
+			return
+		}
+
+		ip := net.IP(buf[4:8])
+		port := binary.BigEndian.Uint16(buf[8:10])
+
+		c2, err := net.DialTCP("tcp", nil, &net.TCPAddr{IP: ip, Port: int(port)})
+		if err != nil {
+			t.Errorf("dial failed; %v", err)
+			return
+		}
+		defer c2.Close()
+		done := make(chan struct{})
+		go func() {
+			_, _ = io.Copy(c1, c2)
+			close(done)
+		}()
+		_, _ = io.Copy(c2, c1)
+		<-done
+	}()
+
+	purl, err := url.Parse("socks5://" + proxyListener.Addr().String())
+	if err != nil {
+		t.Fatalf("parse failed: %v", err)
+	}
+
+	cstDialer := cstDialer // make local copy for modification on next line.
+	cstDialer.Proxy = http.ProxyURL(purl)
+
+	ws, _, err := cstDialer.Dial(s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+func TestTracingDialWithContext(t *testing.T) {
+
+	var headersWrote, requestWrote, getConn, gotConn, connectDone, gotFirstResponseByte bool
+	trace := &httptrace.ClientTrace{
+		WroteHeaders: func() {
+			headersWrote = true
+		},
+		WroteRequest: func(httptrace.WroteRequestInfo) {
+			requestWrote = true
+		},
+		GetConn: func(hostPort string) {
+			getConn = true
+		},
+		GotConn: func(info httptrace.GotConnInfo) {
+			gotConn = true
+		},
+		ConnectDone: func(network, addr string, err error) {
+			connectDone = true
+		},
+		GotFirstResponseByte: func() {
+			gotFirstResponseByte = true
+		},
+	}
+	ctx := httptrace.WithClientTrace(context.Background(), trace)
+
+	s := newTLSServer(t)
+	defer s.Close()
+
+	d := cstDialer
+	d.TLSClientConfig = &tls.Config{RootCAs: rootCAs(t, s.Server)}
+
+	ws, _, err := d.DialContext(ctx, s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+
+	if !headersWrote {
+		t.Fatal("Headers was not written")
+	}
+	if !requestWrote {
+		t.Fatal("Request was not written")
+	}
+	if !getConn {
+		t.Fatal("getConn was not called")
+	}
+	if !gotConn {
+		t.Fatal("gotConn was not called")
+	}
+	if !connectDone {
+		t.Fatal("connectDone was not called")
+	}
+	if !gotFirstResponseByte {
+		t.Fatal("GotFirstResponseByte was not called")
+	}
+
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+func TestEmptyTracingDialWithContext(t *testing.T) {
+
+	trace := &httptrace.ClientTrace{}
+	ctx := httptrace.WithClientTrace(context.Background(), trace)
+
+	s := newTLSServer(t)
+	defer s.Close()
+
+	d := cstDialer
+	d.TLSClientConfig = &tls.Config{RootCAs: rootCAs(t, s.Server)}
+
+	ws, _, err := d.DialContext(ctx, s.URL, nil)
+	if err != nil {
+		t.Fatalf("Dial: %v", err)
+	}
+
+	defer ws.Close()
+	sendRecv(t, ws)
+}
+
+// TestNetDialConnect tests selection of dial method between NetDial, NetDialContext, NetDialTLS or NetDialTLSContext
+func TestNetDialConnect(t *testing.T) {
+
+	upgrader := Upgrader{}
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if IsWebSocketUpgrade(r) {
+			c, err := upgrader.Upgrade(w, r, http.Header{"X-Test-Host": {r.Host}})
+			if err != nil {
+				t.Fatal(err)
+			}
+			c.Close()
+		} else {
+			w.Header().Set("X-Test-Host", r.Host)
+		}
+	})
+
+	server := httptest.NewServer(handler)
+	defer server.Close()
+
+	tlsServer := httptest.NewTLSServer(handler)
+	defer tlsServer.Close()
+
+	testUrls := map[*httptest.Server]string{
+		server:    "ws://" + server.Listener.Addr().String() + "/",
+		tlsServer: "wss://" + tlsServer.Listener.Addr().String() + "/",
+	}
+
+	cas := rootCAs(t, tlsServer)
+	tlsConfig := &tls.Config{
+		RootCAs:            cas,
+		ServerName:         "example.com",
+		InsecureSkipVerify: false,
+	}
+
+	tests := []struct {
+		name              string
+		server            *httptest.Server // server to use
+		netDial           func(network, addr string) (net.Conn, error)
+		netDialContext    func(ctx context.Context, network, addr string) (net.Conn, error)
+		netDialTLSContext func(ctx context.Context, network, addr string) (net.Conn, error)
+		tlsClientConfig   *tls.Config
+	}{
+
+		{
+			name:   "HTTP server, all NetDial* defined, shall use NetDialContext",
+			server: server,
+			netDial: func(network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDial should not be called")
+			},
+			netDialContext: func(_ context.Context, network, addr string) (net.Conn, error) {
+				return net.Dial(network, addr)
+			},
+			netDialTLSContext: func(_ context.Context, network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDialTLSContext should not be called")
+			},
+			tlsClientConfig: nil,
+		},
+		{
+			name:              "HTTP server, all NetDial* undefined",
+			server:            server,
+			netDial:           nil,
+			netDialContext:    nil,
+			netDialTLSContext: nil,
+			tlsClientConfig:   nil,
+		},
+		{
+			name:   "HTTP server, NetDialContext undefined, shall fallback to NetDial",
+			server: server,
+			netDial: func(network, addr string) (net.Conn, error) {
+				return net.Dial(network, addr)
+			},
+			netDialContext: nil,
+			netDialTLSContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDialTLSContext should not be called")
+			},
+			tlsClientConfig: nil,
+		},
+		{
+			name:   "HTTPS server, all NetDial* defined, shall use NetDialTLSContext",
+			server: tlsServer,
+			netDial: func(network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDial should not be called")
+			},
+			netDialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDialContext should not be called")
+			},
+			netDialTLSContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				netConn, err := net.Dial(network, addr)
+				if err != nil {
+					return nil, err
+				}
+				tlsConn := tls.Client(netConn, tlsConfig)
+				err = tlsConn.Handshake()
+				if err != nil {
+					return nil, err
+				}
+				return tlsConn, nil
+			},
+			tlsClientConfig: nil,
+		},
+		{
+			name:   "HTTPS server, NetDialTLSContext undefined, shall fallback to NetDialContext and do handshake",
+			server: tlsServer,
+			netDial: func(network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDial should not be called")
+			},
+			netDialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return net.Dial(network, addr)
+			},
+			netDialTLSContext: nil,
+			tlsClientConfig:   tlsConfig,
+		},
+		{
+			name:   "HTTPS server, NetDialTLSContext and NetDialContext undefined, shall fallback to NetDial and do handshake",
+			server: tlsServer,
+			netDial: func(network, addr string) (net.Conn, error) {
+				return net.Dial(network, addr)
+			},
+			netDialContext:    nil,
+			netDialTLSContext: nil,
+			tlsClientConfig:   tlsConfig,
+		},
+		{
+			name:              "HTTPS server, all NetDial* undefined",
+			server:            tlsServer,
+			netDial:           nil,
+			netDialContext:    nil,
+			netDialTLSContext: nil,
+			tlsClientConfig:   tlsConfig,
+		},
+		{
+			name:   "HTTPS server, all NetDialTLSContext defined, dummy TlsClientConfig defined, shall not do handshake",
+			server: tlsServer,
+			netDial: func(network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDial should not be called")
+			},
+			netDialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return nil, errors.New("NetDialContext should not be called")
+			},
+			netDialTLSContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				netConn, err := net.Dial(network, addr)
+				if err != nil {
+					return nil, err
+				}
+				tlsConn := tls.Client(netConn, tlsConfig)
+				err = tlsConn.Handshake()
+				if err != nil {
+					return nil, err
+				}
+				return tlsConn, nil
+			},
+			tlsClientConfig: &tls.Config{
+				RootCAs:            nil,
+				ServerName:         "badserver.com",
+				InsecureSkipVerify: false,
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		dialer := Dialer{
+			NetDial:           tc.netDial,
+			NetDialContext:    tc.netDialContext,
+			NetDialTLSContext: tc.netDialTLSContext,
+			TLSClientConfig:   tc.tlsClientConfig,
+		}
+
+		// Test websocket dial
+		c, _, err := dialer.Dial(testUrls[tc.server], nil)
+		if err != nil {
+			t.Errorf("FAILED %s, err: %s", tc.name, err.Error())
+		} else {
+			c.Close()
+		}
+	}
+}
+func TestNextProtos(t *testing.T) {
+	ts := httptest.NewUnstartedServer(
+		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}),
+	)
+	ts.EnableHTTP2 = true
+	ts.StartTLS()
+	defer ts.Close()
+
+	d := Dialer{
+		TLSClientConfig: ts.Client().Transport.(*http.Transport).TLSClientConfig,
+	}
+
+	r, err := ts.Client().Get(ts.URL)
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	r.Body.Close()
+
+	// Asserts that Dialer.TLSClientConfig.NextProtos contains "h2"
+	// after the Client.Get call from net/http above.
+	var containsHTTP2 bool = false
+	for _, proto := range d.TLSClientConfig.NextProtos {
+		if proto == "h2" {
+			containsHTTP2 = true
+		}
+	}
+	if !containsHTTP2 {
+		t.Fatalf("Dialer.TLSClientConfig.NextProtos does not contain \"h2\"")
+	}
+
+	_, _, err = d.Dial(makeWsProto(ts.URL), nil)
+	if err == nil {
+		t.Fatalf("Dial succeeded, expect fail ")
+	}
+}
+
+type dataBeforeHandshakeResponseWriter struct {
+	http.ResponseWriter
+}
+
+type dataBeforeHandshakeConnection struct {
+	net.Conn
+	io.Reader
+}
+
+func (c *dataBeforeHandshakeConnection) Read(p []byte) (int, error) {
+	return c.Reader.Read(p)
+}
+
+func (w dataBeforeHandshakeResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	// Example single-frame masked text message from section 5.7 of the RFC.
+	message := []byte{0x81, 0x85, 0x37, 0xfa, 0x21, 0x3d, 0x7f, 0x9f, 0x4d, 0x51, 0x58}
+	n := len(message) / 2
+
+	c, rw, err := http.NewResponseController(w.ResponseWriter).Hijack()
+	if rw != nil {
+		// Load first part of message into bufio.Reader. If the websocket
+		// connection reads more than n bytes from the bufio.Reader, then the
+		// test will fail with an unexpected EOF error.
+		rw.Reader.Reset(bytes.NewReader(message[:n]))
+		rw.Reader.Peek(n)
+	}
+	if c != nil {
+		// Inject second part of message before data read from the network connection.
+		c = &dataBeforeHandshakeConnection{
+			Conn:   c,
+			Reader: io.MultiReader(bytes.NewReader(message[n:]), c),
+		}
+	}
+	return c, rw, err
+}
+
+func TestDataReceivedBeforeHandshake(t *testing.T) {
+	s := newServer(t)
+	defer s.Close()
+
+	origHandler := s.Server.Config.Handler
+	s.Server.Config.Handler = http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			origHandler.ServeHTTP(dataBeforeHandshakeResponseWriter{w}, r)
+		})
+
+	for _, readBufferSize := range []int{0, 1024} {
+		t.Run(fmt.Sprintf("ReadBufferSize=%d", readBufferSize), func(t *testing.T) {
+			dialer := cstDialer
+			dialer.ReadBufferSize = readBufferSize
+			ws, _, err := cstDialer.Dial(s.URL, nil)
+			if err != nil {
+				t.Fatalf("Dial: %v", err)
+			}
+			defer ws.Close()
+			_, m, err := ws.ReadMessage()
+			if err != nil || string(m) != "Hello" {
+				t.Fatalf("ReadMessage() = %q, %v, want \"Hello\", nil", m, err)
+			}
+		})
+	}
+}
+// Copyright 2014 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+var hostPortNoPortTests = []struct {
+	u                    *url.URL
+	hostPort, hostNoPort string
+}{
+	{&url.URL{Scheme: "ws", Host: "example.com"}, "example.com:80", "example.com"},
+	{&url.URL{Scheme: "wss", Host: "example.com"}, "example.com:443", "example.com"},
+	{&url.URL{Scheme: "ws", Host: "example.com:7777"}, "example.com:7777", "example.com"},
+	{&url.URL{Scheme: "wss", Host: "example.com:7777"}, "example.com:7777", "example.com"},
+}
+
+func TestHostPortNoPort(t *testing.T) {
+	for _, tt := range hostPortNoPortTests {
+		hostPort, hostNoPort := hostPortNoPort(tt.u)
+		if hostPort != tt.hostPort {
+			t.Errorf("hostPortNoPort(%v) returned hostPort %q, want %q", tt.u, hostPort, tt.hostPort)
+		}
+		if hostNoPort != tt.hostNoPort {
+			t.Errorf("hostPortNoPort(%v) returned hostNoPort %q, want %q", tt.u, hostNoPort, tt.hostNoPort)
+		}
+	}
+}
+
+type nopCloser struct{ io.Writer }
+
+func (nopCloser) Close() error { return nil }
+
+func TestTruncWriter(t *testing.T) {
+	const data = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijlkmnopqrstuvwxyz987654321"
+	for n := 1; n <= 10; n++ {
+		var b bytes.Buffer
+		w := &truncWriter{w: nopCloser{&b}}
+		p := []byte(data)
+		for len(p) > 0 {
+			m := len(p)
+			if m > n {
+				m = n
+			}
+			_, _ = w.Write(p[:m])
+			p = p[m:]
+		}
+		if b.String() != data[:len(data)-len(w.p)] {
+			t.Errorf("%d: %q", n, b.String())
+		}
+	}
+}
+
+func textMessages(num int) [][]byte {
+	messages := make([][]byte, num)
+	for i := 0; i < num; i++ {
+		msg := fmt.Sprintf("planet: %d, country: %d, city: %d, street: %d", i, i, i, i)
+		messages[i] = []byte(msg)
+	}
+	return messages
+}
+
+func BenchmarkWriteNoCompression(b *testing.B) {
+	w := io.Discard
+	c := newTestConn(nil, w, false)
+	messages := textMessages(100)
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = c.WriteMessage(TextMessage, messages[i%len(messages)])
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkWriteWithCompression(b *testing.B) {
+	w := io.Discard
+	c := newTestConn(nil, w, false)
+	messages := textMessages(100)
+	c.enableWriteCompression = true
+	c.newCompressionWriter = compressNoContextTakeover
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = c.WriteMessage(TextMessage, messages[i%len(messages)])
+	}
+	b.ReportAllocs()
+}
+
+func TestValidCompressionLevel(t *testing.T) {
+	c := newTestConn(nil, nil, false)
+	for _, level := range []int{minCompressionLevel - 1, maxCompressionLevel + 1} {
+		if err := c.SetCompressionLevel(level); err == nil {
+			t.Errorf("no error for level %d", level)
+		}
+	}
+	for _, level := range []int{minCompressionLevel, maxCompressionLevel} {
+		if err := c.SetCompressionLevel(level); err != nil {
+			t.Errorf("error for level %d", level)
+		}
+	}
+}
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+// broadcastBench allows to run broadcast benchmarks.
+// In every broadcast benchmark we create many connections, then send the same
+// message into every connection and wait for all writes complete. This emulates
+// an application where many connections listen to the same data - i.e. PUB/SUB
+// scenarios with many subscribers in one channel.
+type broadcastBench struct {
+	w           io.Writer
+	closeCh     chan struct{}
+	doneCh      chan struct{}
+	count       int32
+	conns       []*broadcastConn
+	compression bool
+	usePrepared bool
+}
+
+type broadcastMessage struct {
+	payload  []byte
+	prepared *PreparedMessage
+}
+
+type broadcastConn struct {
+	conn  *Conn
+	msgCh chan *broadcastMessage
+}
+
+func newBroadcastConn(c *Conn) *broadcastConn {
+	return &broadcastConn{
+		conn:  c,
+		msgCh: make(chan *broadcastMessage, 1),
+	}
+}
+
+func newBroadcastBench(usePrepared, compression bool) *broadcastBench {
+	bench := &broadcastBench{
+		w:           io.Discard,
+		doneCh:      make(chan struct{}),
+		closeCh:     make(chan struct{}),
+		usePrepared: usePrepared,
+		compression: compression,
+	}
+	bench.makeConns(10000)
+	return bench
+}
+
+func (b *broadcastBench) makeConns(numConns int) {
+	conns := make([]*broadcastConn, numConns)
+
+	for i := 0; i < numConns; i++ {
+		c := newTestConn(nil, b.w, true)
+		if b.compression {
+			c.enableWriteCompression = true
+			c.newCompressionWriter = compressNoContextTakeover
+		}
+		conns[i] = newBroadcastConn(c)
+		go func(c *broadcastConn) {
+			for {
+				select {
+				case msg := <-c.msgCh:
+					if msg.prepared != nil {
+						_ = c.conn.WritePreparedMessage(msg.prepared)
+					} else {
+						_ = c.conn.WriteMessage(TextMessage, msg.payload)
+					}
+					val := atomic.AddInt32(&b.count, 1)
+					if val%int32(numConns) == 0 {
+						b.doneCh <- struct{}{}
+					}
+				case <-b.closeCh:
+					return
+				}
+			}
+		}(conns[i])
+	}
+	b.conns = conns
+}
+
+func (b *broadcastBench) close() {
+	close(b.closeCh)
+}
+
+func (b *broadcastBench) broadcastOnce(msg *broadcastMessage) {
+	for _, c := range b.conns {
+		c.msgCh <- msg
+	}
+	<-b.doneCh
+}
+
+func BenchmarkBroadcast(b *testing.B) {
+	benchmarks := []struct {
+		name        string
+		usePrepared bool
+		compression bool
+	}{
+		{"NoCompression", false, false},
+		{"Compression", false, true},
+		{"NoCompressionPrepared", true, false},
+		{"CompressionPrepared", true, true},
+	}
+	payload := textMessages(1)[0]
+	for _, bm := range benchmarks {
+		b.Run(bm.name, func(b *testing.B) {
+			bench := newBroadcastBench(bm.usePrepared, bm.compression)
+			defer bench.close()
+			b.ResetTimer()
+			for i := 0; i < b.N; i++ {
+				message := &broadcastMessage{
+					payload: payload,
+				}
+				if bench.usePrepared {
+					pm, _ := NewPreparedMessage(TextMessage, message.payload)
+					message.prepared = pm
+				}
+				bench.broadcastOnce(message)
+			}
+			b.ReportAllocs()
+		})
+	}
+}
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+var _ net.Error = errWriteTimeout
+
+type fakeNetConn struct {
+	io.Reader
+	io.Writer
+}
+
+func (c fakeNetConn) Close() error                       { return nil }
+func (c fakeNetConn) LocalAddr() net.Addr                { return localAddr }
+func (c fakeNetConn) RemoteAddr() net.Addr               { return remoteAddr }
+func (c fakeNetConn) SetDeadline(t time.Time) error      { return nil }
+func (c fakeNetConn) SetReadDeadline(t time.Time) error  { return nil }
+func (c fakeNetConn) SetWriteDeadline(t time.Time) error { return nil }
+
+type fakeAddr int
+
+var (
+	localAddr  = fakeAddr(1)
+	remoteAddr = fakeAddr(2)
+)
+
+func (a fakeAddr) Network() string {
+	return "net"
+}
+
+func (a fakeAddr) String() string {
+	return "str"
+}
+
+// newTestConn creates a connection backed by a fake network connection using
+// default values for buffering.
+func newTestConn(r io.Reader, w io.Writer, isServer bool) *Conn {
+	return newConn(fakeNetConn{Reader: r, Writer: w}, isServer, 1024, 1024, nil, nil, nil)
+}
+
+func TestFraming(t *testing.T) {
+	frameSizes := []int{
+		0, 1, 2, 124, 125, 126, 127, 128, 129, 65534, 65535,
+		// 65536, 65537
+	}
+	var readChunkers = []struct {
+		name string
+		f    func(io.Reader) io.Reader
+	}{
+		{"half", iotest.HalfReader},
+		{"one", iotest.OneByteReader},
+		{"asis", func(r io.Reader) io.Reader { return r }},
+	}
+	writeBuf := make([]byte, 65537)
+	for i := range writeBuf {
+		writeBuf[i] = byte(i)
+	}
+	var writers = []struct {
+		name string
+		f    func(w io.Writer, n int) (int, error)
+	}{
+		{"iocopy", func(w io.Writer, n int) (int, error) {
+			nn, err := io.Copy(w, bytes.NewReader(writeBuf[:n]))
+			return int(nn), err
+		}},
+		{"write", func(w io.Writer, n int) (int, error) {
+			return w.Write(writeBuf[:n])
+		}},
+		{"string", func(w io.Writer, n int) (int, error) {
+			return io.WriteString(w, string(writeBuf[:n]))
+		}},
+	}
+
+	for _, compress := range []bool{false, true} {
+		for _, isServer := range []bool{true, false} {
+			for _, chunker := range readChunkers {
+
+				var connBuf bytes.Buffer
+				wc := newTestConn(nil, &connBuf, isServer)
+				rc := newTestConn(chunker.f(&connBuf), nil, !isServer)
+				if compress {
+					wc.newCompressionWriter = compressNoContextTakeover
+					rc.newDecompressionReader = decompressNoContextTakeover
+				}
+				for _, n := range frameSizes {
+					for _, writer := range writers {
+						name := fmt.Sprintf("z:%v, s:%v, r:%s, n:%d w:%s", compress, isServer, chunker.name, n, writer.name)
+
+						w, err := wc.NextWriter(TextMessage)
+						if err != nil {
+							t.Errorf("%s: wc.NextWriter() returned %v", name, err)
+							continue
+						}
+						nn, err := writer.f(w, n)
+						if err != nil || nn != n {
+							t.Errorf("%s: w.Write(writeBuf[:n]) returned %d, %v", name, nn, err)
+							continue
+						}
+						err = w.Close()
+						if err != nil {
+							t.Errorf("%s: w.Close() returned %v", name, err)
+							continue
+						}
+
+						opCode, r, err := rc.NextReader()
+						if err != nil || opCode != TextMessage {
+							t.Errorf("%s: NextReader() returned %d, r, %v", name, opCode, err)
+							continue
+						}
+
+						t.Logf("frame size: %d", n)
+						rbuf, err := io.ReadAll(r)
+						if err != nil {
+							t.Errorf("%s: ReadFull() returned rbuf, %v", name, err)
+							continue
+						}
+
+						if len(rbuf) != n {
+							t.Errorf("%s: len(rbuf) is %d, want %d", name, len(rbuf), n)
+							continue
+						}
+
+						for i, b := range rbuf {
+							if byte(i) != b {
+								t.Errorf("%s: bad byte at offset %d", name, i)
+								break
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+}
+
+func TestWriteControlDeadline(t *testing.T) {
+	t.Parallel()
+	message := []byte("hello")
+	var connBuf bytes.Buffer
+	c := newTestConn(nil, &connBuf, true)
+	if err := c.WriteControl(PongMessage, message, time.Time{}); err != nil {
+		t.Errorf("WriteControl(..., zero deadline) = %v, want nil", err)
+	}
+	if err := c.WriteControl(PongMessage, message, time.Now().Add(time.Second)); err != nil {
+		t.Errorf("WriteControl(..., future deadline) = %v, want nil", err)
+	}
+	if err := c.WriteControl(PongMessage, message, time.Now().Add(-time.Second)); err == nil {
+		t.Errorf("WriteControl(..., past deadline) = nil, want timeout error")
+	}
+}
+
+func TestConcurrencyWriteControl(t *testing.T) {
+	const message = "this is a ping/pong messsage"
+	loop := 10
+	workers := 10
+	for i := 0; i < loop; i++ {
+		var connBuf bytes.Buffer
+
+		wg := sync.WaitGroup{}
+		wc := newTestConn(nil, &connBuf, true)
+
+		for i := 0; i < workers; i++ {
+			wg.Add(1)
+			go func() {
+				defer wg.Done()
+				if err := wc.WriteControl(PongMessage, []byte(message), time.Now().Add(time.Second)); err != nil {
+					t.Errorf("concurrently wc.WriteControl() returned %v", err)
+				}
+			}()
+		}
+
+		wg.Wait()
+		wc.Close()
+	}
+}
+
+func TestControl(t *testing.T) {
+	const message = "this is a ping/pong message"
+	for _, isServer := range []bool{true, false} {
+		for _, isWriteControl := range []bool{true, false} {
+			name := fmt.Sprintf("s:%v, wc:%v", isServer, isWriteControl)
+			var connBuf bytes.Buffer
+			wc := newTestConn(nil, &connBuf, isServer)
+			rc := newTestConn(&connBuf, nil, !isServer)
+			if isWriteControl {
+				_ = wc.WriteControl(PongMessage, []byte(message), time.Now().Add(time.Second))
+			} else {
+				w, err := wc.NextWriter(PongMessage)
+				if err != nil {
+					t.Errorf("%s: wc.NextWriter() returned %v", name, err)
+					continue
+				}
+				if _, err := w.Write([]byte(message)); err != nil {
+					t.Errorf("%s: w.Write() returned %v", name, err)
+					continue
+				}
+				if err := w.Close(); err != nil {
+					t.Errorf("%s: w.Close() returned %v", name, err)
+					continue
+				}
+				var actualMessage string
+				rc.SetPongHandler(func(s string) error { actualMessage = s; return nil })
+				_, _, _ = rc.NextReader()
+				if actualMessage != message {
+					t.Errorf("%s: pong=%q, want %q", name, actualMessage, message)
+					continue
+				}
+			}
+		}
+	}
+}
+
+// simpleBufferPool is an implementation of BufferPool for TestWriteBufferPool.
+type simpleBufferPool struct {
+	v interface{}
+}
+
+func (p *simpleBufferPool) Get() interface{} {
+	v := p.v
+	p.v = nil
+	return v
+}
+
+func (p *simpleBufferPool) Put(v interface{}) {
+	p.v = v
+}
+
+func TestWriteBufferPool(t *testing.T) {
+	const message = "Now is the time for all good people to come to the aid of the party."
+
+	var buf bytes.Buffer
+	var pool simpleBufferPool
+	rc := newTestConn(&buf, nil, false)
+
+	// Specify writeBufferSize smaller than message size to ensure that pooling
+	// works with fragmented messages.
+	wc := newConn(fakeNetConn{Writer: &buf}, true, 1024, len(message)-1, &pool, nil, nil)
+
+	if wc.writeBuf != nil {
+		t.Fatal("writeBuf not nil after create")
+	}
+
+	// Part 1: test NextWriter/Write/Close
+
+	w, err := wc.NextWriter(TextMessage)
+	if err != nil {
+		t.Fatalf("wc.NextWriter() returned %v", err)
+	}
+
+	if wc.writeBuf == nil {
+		t.Fatal("writeBuf is nil after NextWriter")
+	}
+
+	writeBufAddr := &wc.writeBuf[0]
+
+	if _, err := io.WriteString(w, message); err != nil {
+		t.Fatalf("io.WriteString(w, message) returned %v", err)
+	}
+
+	if err := w.Close(); err != nil {
+		t.Fatalf("w.Close() returned %v", err)
+	}
+
+	if wc.writeBuf != nil {
+		t.Fatal("writeBuf not nil after w.Close()")
+	}
+
+	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
+		t.Fatal("writeBuf not returned to pool")
+	}
+
+	opCode, p, err := rc.ReadMessage()
+	if opCode != TextMessage || err != nil {
+		t.Fatalf("ReadMessage() returned %d, p, %v", opCode, err)
+	}
+
+	if s := string(p); s != message {
+		t.Fatalf("message is %s, want %s", s, message)
+	}
+
+	// Part 2: Test WriteMessage.
+
+	if err := wc.WriteMessage(TextMessage, []byte(message)); err != nil {
+		t.Fatalf("wc.WriteMessage() returned %v", err)
+	}
+
+	if wc.writeBuf != nil {
+		t.Fatal("writeBuf not nil after wc.WriteMessage()")
+	}
+
+	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
+		t.Fatal("writeBuf not returned to pool after WriteMessage")
+	}
+
+	opCode, p, err = rc.ReadMessage()
+	if opCode != TextMessage || err != nil {
+		t.Fatalf("ReadMessage() returned %d, p, %v", opCode, err)
+	}
+
+	if s := string(p); s != message {
+		t.Fatalf("message is %s, want %s", s, message)
+	}
+}
+
+// TestWriteBufferPoolSync ensures that *sync.Pool works as a buffer pool.
+func TestWriteBufferPoolSync(t *testing.T) {
+	var buf bytes.Buffer
+	var pool sync.Pool
+	wc := newConn(fakeNetConn{Writer: &buf}, true, 1024, 1024, &pool, nil, nil)
+	rc := newTestConn(&buf, nil, false)
+
+	const message = "Hello World!"
+	for i := 0; i < 3; i++ {
+		if err := wc.WriteMessage(TextMessage, []byte(message)); err != nil {
+			t.Fatalf("wc.WriteMessage() returned %v", err)
+		}
+		opCode, p, err := rc.ReadMessage()
+		if opCode != TextMessage || err != nil {
+			t.Fatalf("ReadMessage() returned %d, p, %v", opCode, err)
+		}
+		if s := string(p); s != message {
+			t.Fatalf("message is %s, want %s", s, message)
+		}
+	}
+}
+
+// errorWriter is an io.Writer than returns an error on all writes.
+type errorWriter struct{}
+
+func (ew errorWriter) Write(p []byte) (int, error) { return 0, errors.New("error") }
+
+// TestWriteBufferPoolError ensures that buffer is returned to pool after error
+// on write.
+func TestWriteBufferPoolError(t *testing.T) {
+
+	// Part 1: Test NextWriter/Write/Close
+
+	var pool simpleBufferPool
+	wc := newConn(fakeNetConn{Writer: errorWriter{}}, true, 1024, 1024, &pool, nil, nil)
+
+	w, err := wc.NextWriter(TextMessage)
+	if err != nil {
+		t.Fatalf("wc.NextWriter() returned %v", err)
+	}
+
+	if wc.writeBuf == nil {
+		t.Fatal("writeBuf is nil after NextWriter")
+	}
+
+	writeBufAddr := &wc.writeBuf[0]
+
+	if _, err := io.WriteString(w, "Hello"); err != nil {
+		t.Fatalf("io.WriteString(w, message) returned %v", err)
+	}
+
+	if err := w.Close(); err == nil {
+		t.Fatalf("w.Close() did not return error")
+	}
+
+	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
+		t.Fatal("writeBuf not returned to pool")
+	}
+
+	// Part 2: Test WriteMessage
+
+	wc = newConn(fakeNetConn{Writer: errorWriter{}}, true, 1024, 1024, &pool, nil, nil)
+
+	if err := wc.WriteMessage(TextMessage, []byte("Hello")); err == nil {
+		t.Fatalf("wc.WriteMessage did not return error")
+	}
+
+	if wpd, ok := pool.v.(writePoolData); !ok || len(wpd.buf) == 0 || &wpd.buf[0] != writeBufAddr {
+		t.Fatal("writeBuf not returned to pool")
+	}
+}
+
+func TestCloseFrameBeforeFinalMessageFrame(t *testing.T) {
+	const bufSize = 512
+
+	expectedErr := &CloseError{Code: CloseNormalClosure, Text: "hello"}
+
+	var b1, b2 bytes.Buffer
+	wc := newConn(&fakeNetConn{Reader: nil, Writer: &b1}, false, 1024, bufSize, nil, nil, nil)
+	rc := newTestConn(&b1, &b2, true)
+
+	w, _ := wc.NextWriter(BinaryMessage)
+	_, _ = w.Write(make([]byte, bufSize+bufSize/2))
+	_ = wc.WriteControl(CloseMessage, FormatCloseMessage(expectedErr.Code, expectedErr.Text), time.Now().Add(10*time.Second))
+	w.Close()
+
+	op, r, err := rc.NextReader()
+	if op != BinaryMessage || err != nil {
+		t.Fatalf("NextReader() returned %d, %v", op, err)
+	}
+	_, err = io.Copy(io.Discard, r)
+	if !reflect.DeepEqual(err, expectedErr) {
+		t.Fatalf("io.Copy() returned %v, want %v", err, expectedErr)
+	}
+	_, _, err = rc.NextReader()
+	if !reflect.DeepEqual(err, expectedErr) {
+		t.Fatalf("NextReader() returned %v, want %v", err, expectedErr)
+	}
+}
+
+func TestEOFWithinFrame(t *testing.T) {
+	const bufSize = 64
+
+	for n := 0; ; n++ {
+		var b bytes.Buffer
+		wc := newTestConn(nil, &b, false)
+		rc := newTestConn(&b, nil, true)
+
+		w, _ := wc.NextWriter(BinaryMessage)
+		_, _ = w.Write(make([]byte, bufSize))
+		w.Close()
+
+		if n >= b.Len() {
+			break
+		}
+		b.Truncate(n)
+
+		op, r, err := rc.NextReader()
+		if err == errUnexpectedEOF {
+			continue
+		}
+		if op != BinaryMessage || err != nil {
+			t.Fatalf("%d: NextReader() returned %d, %v", n, op, err)
+		}
+		_, err = io.Copy(io.Discard, r)
+		if err != errUnexpectedEOF {
+			t.Fatalf("%d: io.Copy() returned %v, want %v", n, err, errUnexpectedEOF)
+		}
+		_, _, err = rc.NextReader()
+		if err != errUnexpectedEOF {
+			t.Fatalf("%d: NextReader() returned %v, want %v", n, err, errUnexpectedEOF)
+		}
+	}
+}
+
+func TestEOFBeforeFinalFrame(t *testing.T) {
+	const bufSize = 512
+
+	var b1, b2 bytes.Buffer
+	wc := newConn(&fakeNetConn{Writer: &b1}, false, 1024, bufSize, nil, nil, nil)
+	rc := newTestConn(&b1, &b2, true)
+
+	w, _ := wc.NextWriter(BinaryMessage)
+	_, _ = w.Write(make([]byte, bufSize+bufSize/2))
+
+	op, r, err := rc.NextReader()
+	if op != BinaryMessage || err != nil {
+		t.Fatalf("NextReader() returned %d, %v", op, err)
+	}
+	_, err = io.Copy(io.Discard, r)
+	if err != errUnexpectedEOF {
+		t.Fatalf("io.Copy() returned %v, want %v", err, errUnexpectedEOF)
+	}
+	_, _, err = rc.NextReader()
+	if err != errUnexpectedEOF {
+		t.Fatalf("NextReader() returned %v, want %v", err, errUnexpectedEOF)
+	}
+}
+
+func TestWriteAfterMessageWriterClose(t *testing.T) {
+	wc := newTestConn(nil, &bytes.Buffer{}, false)
+	w, _ := wc.NextWriter(BinaryMessage)
+	_, _ = io.WriteString(w, "hello")
+	if err := w.Close(); err != nil {
+		t.Fatalf("unexpected error closing message writer, %v", err)
+	}
+
+	if _, err := io.WriteString(w, "world"); err == nil {
+		t.Fatalf("no error writing after close")
+	}
+
+	w, _ = wc.NextWriter(BinaryMessage)
+	_, _ = io.WriteString(w, "hello")
+
+	// close w by getting next writer
+	_, err := wc.NextWriter(BinaryMessage)
+	if err != nil {
+		t.Fatalf("unexpected error getting next writer, %v", err)
+	}
+
+	if _, err := io.WriteString(w, "world"); err == nil {
+		t.Fatalf("no error writing after close")
+	}
+}
+
+func TestReadLimit(t *testing.T) {
+	t.Run("Test ReadLimit is enforced", func(t *testing.T) {
+		const readLimit = 512
+		message := make([]byte, readLimit+1)
+
+		var b1, b2 bytes.Buffer
+		wc := newConn(&fakeNetConn{Writer: &b1}, false, 1024, readLimit-2, nil, nil, nil)
+		rc := newTestConn(&b1, &b2, true)
+		rc.SetReadLimit(readLimit)
+
+		// Send message at the limit with interleaved pong.
+		w, _ := wc.NextWriter(BinaryMessage)
+		_, _ = w.Write(message[:readLimit-1])
+		_ = wc.WriteControl(PongMessage, []byte("this is a pong"), time.Now().Add(10*time.Second))
+		_, _ = w.Write(message[:1])
+		w.Close()
+
+		// Send message larger than the limit.
+		_ = wc.WriteMessage(BinaryMessage, message[:readLimit+1])
+
+		op, _, err := rc.NextReader()
+		if op != BinaryMessage || err != nil {
+			t.Fatalf("1: NextReader() returned %d, %v", op, err)
+		}
+		op, r, err := rc.NextReader()
+		if op != BinaryMessage || err != nil {
+			t.Fatalf("2: NextReader() returned %d, %v", op, err)
+		}
+		_, err = io.Copy(io.Discard, r)
+		if err != ErrReadLimit {
+			t.Fatalf("io.Copy() returned %v", err)
+		}
+	})
+
+	t.Run("Test that ReadLimit cannot be overflowed", func(t *testing.T) {
+		const readLimit = 1
+
+		var b1, b2 bytes.Buffer
+		rc := newTestConn(&b1, &b2, true)
+		rc.SetReadLimit(readLimit)
+
+		// First, send a non-final binary message
+		b1.Write([]byte("\x02\x81"))
+
+		// Mask key
+		b1.Write([]byte("\x00\x00\x00\x00"))
+
+		// First payload
+		b1.Write([]byte("A"))
+
+		// Next, send a negative-length, non-final continuation frame
+		b1.Write([]byte("\x00\xFF\x80\x00\x00\x00\x00\x00\x00\x00"))
+
+		// Mask key
+		b1.Write([]byte("\x00\x00\x00\x00"))
+
+		// Next, send a too long, final continuation frame
+		b1.Write([]byte("\x80\xFF\x00\x00\x00\x00\x00\x00\x00\x05"))
+
+		// Mask key
+		b1.Write([]byte("\x00\x00\x00\x00"))
+
+		// Too-long payload
+		b1.Write([]byte("BCDEF"))
+
+		op, r, err := rc.NextReader()
+		if op != BinaryMessage || err != nil {
+			t.Fatalf("1: NextReader() returned %d, %v", op, err)
+		}
+
+		var buf [10]byte
+		var read int
+		n, err := r.Read(buf[:])
+		if err != nil && err != ErrReadLimit {
+			t.Fatalf("unexpected error testing read limit: %v", err)
+		}
+		read += n
+
+		n, err = r.Read(buf[:])
+		if err != nil && err != ErrReadLimit {
+			t.Fatalf("unexpected error testing read limit: %v", err)
+		}
+		read += n
+
+		if err == nil && read > readLimit {
+			t.Fatalf("read limit exceeded: limit %d, read %d", readLimit, read)
+		}
+	})
+}
+
+func TestAddrs(t *testing.T) {
+	c := newTestConn(nil, nil, true)
+	if c.LocalAddr() != localAddr {
+		t.Errorf("LocalAddr = %v, want %v", c.LocalAddr(), localAddr)
+	}
+	if c.RemoteAddr() != remoteAddr {
+		t.Errorf("RemoteAddr = %v, want %v", c.RemoteAddr(), remoteAddr)
+	}
+}
+
+func TestDeprecatedUnderlyingConn(t *testing.T) {
+	var b1, b2 bytes.Buffer
+	fc := fakeNetConn{Reader: &b1, Writer: &b2}
+	c := newConn(fc, true, 1024, 1024, nil, nil, nil)
+	ul := c.UnderlyingConn()
+	if ul != fc {
+		t.Fatalf("Underlying conn is not what it should be.")
+	}
+}
+
+func TestNetConn(t *testing.T) {
+	var b1, b2 bytes.Buffer
+	fc := fakeNetConn{Reader: &b1, Writer: &b2}
+	c := newConn(fc, true, 1024, 1024, nil, nil, nil)
+	ul := c.NetConn()
+	if ul != fc {
+		t.Fatalf("Underlying conn is not what it should be.")
+	}
+}
+
+func TestBufioReadBytes(t *testing.T) {
+	// Test calling bufio.ReadBytes for value longer than read buffer size.
+
+	m := make([]byte, 512)
+	m[len(m)-1] = '\n'
+
+	var b1, b2 bytes.Buffer
+	wc := newConn(fakeNetConn{Writer: &b1}, false, len(m)+64, len(m)+64, nil, nil, nil)
+	rc := newConn(fakeNetConn{Reader: &b1, Writer: &b2}, true, len(m)-64, len(m)-64, nil, nil, nil)
+
+	w, _ := wc.NextWriter(BinaryMessage)
+	_, _ = w.Write(m)
+	w.Close()
+
+	op, r, err := rc.NextReader()
+	if op != BinaryMessage || err != nil {
+		t.Fatalf("NextReader() returned %d, %v", op, err)
+	}
+
+	br := bufio.NewReader(r)
+	p, err := br.ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("ReadBytes() returned %v", err)
+	}
+	if len(p) != len(m) {
+		t.Fatalf("read returned %d bytes, want %d bytes", len(p), len(m))
+	}
+}
+
+var closeErrorTests = []struct {
+	err   error
+	codes []int
+	ok    bool
+}{
+	{&CloseError{Code: CloseNormalClosure}, []int{CloseNormalClosure}, true},
+	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived}, false},
+	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived, CloseNormalClosure}, true},
+	{errors.New("hello"), []int{CloseNormalClosure}, false},
+}
+
+func TestCloseError(t *testing.T) {
+	for _, tt := range closeErrorTests {
+		ok := IsCloseError(tt.err, tt.codes...)
+		if ok != tt.ok {
+			t.Errorf("IsCloseError(%#v, %#v) returned %v, want %v", tt.err, tt.codes, ok, tt.ok)
+		}
+	}
+}
+
+var unexpectedCloseErrorTests = []struct {
+	err   error
+	codes []int
+	ok    bool
+}{
+	{&CloseError{Code: CloseNormalClosure}, []int{CloseNormalClosure}, false},
+	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived}, true},
+	{&CloseError{Code: CloseNormalClosure}, []int{CloseNoStatusReceived, CloseNormalClosure}, false},
+	{errors.New("hello"), []int{CloseNormalClosure}, false},
+}
+
+func TestUnexpectedCloseErrors(t *testing.T) {
+	for _, tt := range unexpectedCloseErrorTests {
+		ok := IsUnexpectedCloseError(tt.err, tt.codes...)
+		if ok != tt.ok {
+			t.Errorf("IsUnexpectedCloseError(%#v, %#v) returned %v, want %v", tt.err, tt.codes, ok, tt.ok)
+		}
+	}
+}
+
+type blockingWriter struct {
+	c1, c2 chan struct{}
+}
+
+func (w blockingWriter) Write(p []byte) (int, error) {
+	// Allow main to continue
+	close(w.c1)
+	// Wait for panic in main
+	<-w.c2
+	return len(p), nil
+}
+
+func TestConcurrentWritePanic(t *testing.T) {
+	w := blockingWriter{make(chan struct{}), make(chan struct{})}
+	c := newTestConn(nil, w, false)
+	go func() {
+		_ = c.WriteMessage(TextMessage, []byte{})
+	}()
+
+	// wait for goroutine to block in write.
+	<-w.c1
+
+	defer func() {
+		close(w.c2)
+		if v := recover(); v != nil {
+			return
+		}
+	}()
+
+	_ = c.WriteMessage(TextMessage, []byte{})
+	t.Fatal("should not get here")
+}
+
+type failingReader struct{}
+
+func (r failingReader) Read(p []byte) (int, error) {
+	return 0, io.EOF
+}
+
+func TestFailedConnectionReadPanic(t *testing.T) {
+	c := newTestConn(failingReader{}, nil, false)
+
+	defer func() {
+		if v := recover(); v != nil {
+			return
+		}
+	}()
+
+	for i := 0; i < 20000; i++ {
+		_, _, _ = c.ReadMessage()
+	}
+	t.Fatal("should not get here")
+}
+// Copyright 2019 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+func TestJoinMessages(t *testing.T) {
+	messages := []string{"a", "bc", "def", "ghij", "klmno", "0", "12", "345", "6789"}
+	for _, readChunk := range []int{1, 2, 3, 4, 5, 6, 7} {
+		for _, term := range []string{"", ","} {
+			var connBuf bytes.Buffer
+			wc := newTestConn(nil, &connBuf, true)
+			rc := newTestConn(&connBuf, nil, false)
+			for _, m := range messages {
+				_ = wc.WriteMessage(BinaryMessage, []byte(m))
+			}
+
+			var result bytes.Buffer
+			_, err := io.CopyBuffer(&result, JoinMessages(rc, term), make([]byte, readChunk))
+			if IsUnexpectedCloseError(err, CloseAbnormalClosure) {
+				t.Errorf("readChunk=%d, term=%q: unexpected error %v", readChunk, term, err)
+			}
+			want := strings.Join(messages, term) + term
+			if result.String() != want {
+				t.Errorf("readChunk=%d, term=%q, got %q, want %q", readChunk, term, result.String(), want)
+			}
+		}
+	}
+}
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+func TestJSON(t *testing.T) {
+	var buf bytes.Buffer
+	wc := newTestConn(nil, &buf, true)
+	rc := newTestConn(&buf, nil, false)
+
+	var actual, expect struct {
+		A int
+		B string
+	}
+	expect.A = 1
+	expect.B = "hello"
+
+	if err := wc.WriteJSON(&expect); err != nil {
+		t.Fatal("write", err)
+	}
+
+	if err := rc.ReadJSON(&actual); err != nil {
+		t.Fatal("read", err)
+	}
+
+	if !reflect.DeepEqual(&actual, &expect) {
+		t.Fatal("equal", actual, expect)
+	}
+}
+
+func TestPartialJSONRead(t *testing.T) {
+	var buf0, buf1 bytes.Buffer
+	wc := newTestConn(nil, &buf0, true)
+	rc := newTestConn(&buf0, &buf1, false)
+
+	var v struct {
+		A int
+		B string
+	}
+	v.A = 1
+	v.B = "hello"
+
+	messageCount := 0
+
+	// Partial JSON values.
+
+	data, err := json.Marshal(v)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for i := len(data) - 1; i >= 0; i-- {
+		if err := wc.WriteMessage(TextMessage, data[:i]); err != nil {
+			t.Fatal(err)
+		}
+		messageCount++
+	}
+
+	// Whitespace.
+
+	if err := wc.WriteMessage(TextMessage, []byte(" ")); err != nil {
+		t.Fatal(err)
+	}
+	messageCount++
+
+	// Close.
+
+	if err := wc.WriteMessage(CloseMessage, FormatCloseMessage(CloseNormalClosure, "")); err != nil {
+		t.Fatal(err)
+	}
+
+	for i := 0; i < messageCount; i++ {
+		err := rc.ReadJSON(&v)
+		if err != io.ErrUnexpectedEOF {
+			t.Error("read", i, err)
+		}
+	}
+
+	err = rc.ReadJSON(&v)
+	if _, ok := err.(*CloseError); !ok {
+		t.Error("final", err)
+	}
+}
+
+func TestDeprecatedJSON(t *testing.T) {
+	var buf bytes.Buffer
+	wc := newTestConn(nil, &buf, true)
+	rc := newTestConn(&buf, nil, false)
+
+	var actual, expect struct {
+		A int
+		B string
+	}
+	expect.A = 1
+	expect.B = "hello"
+
+	if err := WriteJSON(wc, &expect); err != nil {
+		t.Fatal("write", err)
+	}
+
+	if err := ReadJSON(rc, &actual); err != nil {
+		t.Fatal("read", err)
+	}
+
+	if !reflect.DeepEqual(&actual, &expect) {
+		t.Fatal("equal", actual, expect)
+	}
+}
+// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.  Use of
+// this source code is governed by a BSD-style license that can be found in the
+// LICENSE file.
+
+// !appengine
+
+
+func maskBytesByByte(key [4]byte, pos int, b []byte) int {
+	for i := range b {
+		b[i] ^= key[pos&3]
+		pos++
+	}
+	return pos & 3
+}
+
+func notzero(b []byte) int {
+	for i := range b {
+		if b[i] != 0 {
+			return i
+		}
+	}
+	return -1
+}
+
+func TestMaskBytes(t *testing.T) {
+	key := [4]byte{1, 2, 3, 4}
+	for size := 1; size <= 1024; size++ {
+		for align := 0; align < wordSize; align++ {
+			for pos := 0; pos < 4; pos++ {
+				b := make([]byte, size+align)[align:]
+				maskBytes(key, pos, b)
+				maskBytesByByte(key, pos, b)
+				if i := notzero(b); i >= 0 {
+					t.Errorf("size:%d, align:%d, pos:%d, offset:%d", size, align, pos, i)
+				}
+			}
+		}
+	}
+}
+
+func BenchmarkMaskBytes(b *testing.B) {
+	for _, size := range []int{2, 4, 8, 16, 32, 512, 1024} {
+		b.Run(fmt.Sprintf("size-%d", size), func(b *testing.B) {
+			for _, align := range []int{wordSize / 2} {
+				b.Run(fmt.Sprintf("align-%d", align), func(b *testing.B) {
+					for _, fn := range []struct {
+						name string
+						fn   func(key [4]byte, pos int, b []byte) int
+					}{
+						{"byte", maskBytesByByte},
+						{"word", maskBytes},
+					} {
+						b.Run(fn.name, func(b *testing.B) {
+							key := newMaskKey()
+							data := make([]byte, size+align)[align:]
+							for i := 0; i < b.N; i++ {
+								fn.fn(key, 0, data)
+							}
+							b.SetBytes(int64(len(data)))
+						})
+					}
+				})
+			}
+		})
+	}
+}
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+var preparedMessageTests = []struct {
+	messageType            int
+	isServer               bool
+	enableWriteCompression bool
+	compressionLevel       int
+}{
+	// Server
+	{TextMessage, true, false, flate.BestSpeed},
+	{TextMessage, true, true, flate.BestSpeed},
+	{TextMessage, true, true, flate.BestCompression},
+	{PingMessage, true, false, flate.BestSpeed},
+	{PingMessage, true, true, flate.BestSpeed},
+
+	// Client
+	{TextMessage, false, false, flate.BestSpeed},
+	{TextMessage, false, true, flate.BestSpeed},
+	{TextMessage, false, true, flate.BestCompression},
+	{PingMessage, false, false, flate.BestSpeed},
+	{PingMessage, false, true, flate.BestSpeed},
+}
+
+func TestPreparedMessage(t *testing.T) {
+	testRand := rand.New(rand.NewSource(99))
+	prevMaskRand := maskRand
+	maskRand = testRand
+	defer func() { maskRand = prevMaskRand }()
+
+	for _, tt := range preparedMessageTests {
+		var data = []byte("this is a test")
+		var buf bytes.Buffer
+		c := newTestConn(nil, &buf, tt.isServer)
+		if tt.enableWriteCompression {
+			c.newCompressionWriter = compressNoContextTakeover
+		}
+		if err := c.SetCompressionLevel(tt.compressionLevel); err != nil {
+			t.Fatal(err)
+		}
+
+		// Seed random number generator for consistent frame mask.
+		testRand.Seed(1234)
+
+		if err := c.WriteMessage(tt.messageType, data); err != nil {
+			t.Fatal(err)
+		}
+		want := buf.String()
+
+		pm, err := NewPreparedMessage(tt.messageType, data)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		// Scribble on data to ensure that NewPreparedMessage takes a snapshot.
+		copy(data, "hello world")
+
+		// Seed random number generator for consistent frame mask.
+		testRand.Seed(1234)
+
+		buf.Reset()
+		if err := c.WritePreparedMessage(pm); err != nil {
+			t.Fatal(err)
+		}
+		got := buf.String()
+
+		if got != want {
+			t.Errorf("write message != prepared message for %+v", tt)
+		}
+	}
+}
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+var subprotocolTests = []struct {
+	h         string
+	protocols []string
+}{
+	{"", nil},
+	{"foo", []string{"foo"}},
+	{"foo,bar", []string{"foo", "bar"}},
+	{"foo, bar", []string{"foo", "bar"}},
+	{" foo, bar", []string{"foo", "bar"}},
+	{" foo, bar ", []string{"foo", "bar"}},
+}
+
+func TestSubprotocols(t *testing.T) {
+	for _, st := range subprotocolTests {
+		r := http.Request{Header: http.Header{"Sec-Websocket-Protocol": {st.h}}}
+		protocols := Subprotocols(&r)
+		if !reflect.DeepEqual(st.protocols, protocols) {
+			t.Errorf("SubProtocols(%q) returned %#v, want %#v", st.h, protocols, st.protocols)
+		}
+	}
+}
+
+var isWebSocketUpgradeTests = []struct {
+	ok bool
+	h  http.Header
+}{
+	{false, http.Header{"Upgrade": {"websocket"}}},
+	{false, http.Header{"Connection": {"upgrade"}}},
+	{true, http.Header{"Connection": {"upgRade"}, "Upgrade": {"WebSocket"}}},
+}
+
+func TestIsWebSocketUpgrade(t *testing.T) {
+	for _, tt := range isWebSocketUpgradeTests {
+		ok := IsWebSocketUpgrade(&http.Request{Header: tt.h})
+		if tt.ok != ok {
+			t.Errorf("IsWebSocketUpgrade(%v) returned %v, want %v", tt.h, ok, tt.ok)
+		}
+	}
+}
+
+func TestSubProtocolSelection(t *testing.T) {
+	upgrader := Upgrader{
+		Subprotocols: []string{"foo", "bar", "baz"},
+	}
+
+	r := http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"foo", "bar"}}}
+	s := upgrader.selectSubprotocol(&r, nil)
+	if s != "foo" {
+		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "foo")
+	}
+
+	r = http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"bar", "foo"}}}
+	s = upgrader.selectSubprotocol(&r, nil)
+	if s != "bar" {
+		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "bar")
+	}
+
+	r = http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"baz"}}}
+	s = upgrader.selectSubprotocol(&r, nil)
+	if s != "baz" {
+		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "baz")
+	}
+
+	r = http.Request{Header: http.Header{"Sec-Websocket-Protocol": {"quux"}}}
+	s = upgrader.selectSubprotocol(&r, nil)
+	if s != "" {
+		t.Errorf("Upgrader.selectSubprotocol returned %v, want %v", s, "empty string")
+	}
+}
+
+var checkSameOriginTests = []struct {
+	ok bool
+	r  *http.Request
+}{
+	{false, &http.Request{Host: "example.org", Header: map[string][]string{"Origin": {"https://other.org"}}}},
+	{true, &http.Request{Host: "example.org", Header: map[string][]string{"Origin": {"https://example.org"}}}},
+	{true, &http.Request{Host: "Example.org", Header: map[string][]string{"Origin": {"https://example.org"}}}},
+}
+
+func TestCheckSameOrigin(t *testing.T) {
+	for _, tt := range checkSameOriginTests {
+		ok := checkSameOrigin(tt.r)
+		if tt.ok != ok {
+			t.Errorf("checkSameOrigin(%+v) returned %v, want %v", tt.r, ok, tt.ok)
+		}
+	}
+}
+
+type reuseTestResponseWriter struct {
+	brw *bufio.ReadWriter
+	http.ResponseWriter
+}
+
+func (resp *reuseTestResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return fakeNetConn{strings.NewReader(""), &bytes.Buffer{}}, resp.brw, nil
+}
+
+var bufioReuseTests = []struct {
+	n     int
+	reuse bool
+}{
+	{4096, true},
+	{128, false},
+}
+
+func xTestBufioReuse(t *testing.T) {
+	for i, tt := range bufioReuseTests {
+		br := bufio.NewReaderSize(strings.NewReader(""), tt.n)
+		bw := bufio.NewWriterSize(&bytes.Buffer{}, tt.n)
+		resp := &reuseTestResponseWriter{
+			brw: bufio.NewReadWriter(br, bw),
+		}
+		upgrader := Upgrader{}
+		c, err := upgrader.Upgrade(resp, &http.Request{
+			Method: http.MethodGet,
+			Header: http.Header{
+				"Upgrade":               []string{"websocket"},
+				"Connection":            []string{"upgrade"},
+				"Sec-Websocket-Key":     []string{"dGhlIHNhbXBsZSBub25jZQ=="},
+				"Sec-Websocket-Version": []string{"13"},
+			}}, nil)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if reuse := c.br == br; reuse != tt.reuse {
+			t.Errorf("%d: buffered reader reuse=%v, want %v", i, reuse, tt.reuse)
+		}
+		writeBuf := bw.AvailableBuffer()
+		if reuse := &c.writeBuf[0] == &writeBuf[0]; reuse != tt.reuse {
+			t.Errorf("%d: write buffer reuse=%v, want %v", i, reuse, tt.reuse)
+		}
+	}
+}
+
+func TestHijack_NotSupported(t *testing.T) {
+	t.Parallel()
+
+	req := httptest.NewRequest(http.MethodGet, "http://example.com", nil)
+	req.Header.Set("Upgrade", "websocket")
+	req.Header.Set("Connection", "upgrade")
+	req.Header.Set("Sec-Websocket-Key", "dGhlIHNhbXBsZSBub25jZQ==")
+	req.Header.Set("Sec-Websocket-Version", "13")
+
+	recorder := httptest.NewRecorder()
+
+	upgrader := Upgrader{}
+	_, err := upgrader.Upgrade(recorder, req, nil)
+
+	if want := (HandshakeError{}); !errors.As(err, &want) || recorder.Code != http.StatusInternalServerError {
+		t.Errorf("want %T and status_code=%d", want, http.StatusInternalServerError)
+		t.Fatalf("got err=%T and status_code=%d", err, recorder.Code)
+	}
+}
+// Copyright 2014 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+var equalASCIIFoldTests = []struct {
+	t, s string
+	eq   bool
+}{
+	{"WebSocket", "websocket", true},
+	{"websocket", "WebSocket", true},
+	{"Öyster", "öyster", false},
+	{"WebSocket", "WetSocket", false},
+}
+
+func TestEqualASCIIFold(t *testing.T) {
+	for _, tt := range equalASCIIFoldTests {
+		eq := equalASCIIFold(tt.s, tt.t)
+		if eq != tt.eq {
+			t.Errorf("equalASCIIFold(%q, %q) = %v, want %v", tt.s, tt.t, eq, tt.eq)
+		}
+	}
+}
+
+var tokenListContainsValueTests = []struct {
+	value string
+	ok    bool
+}{
+	{"WebSocket", true},
+	{"WEBSOCKET", true},
+	{"websocket", true},
+	{"websockets", false},
+	{"x websocket", false},
+	{"websocket x", false},
+	{"other,websocket,more", true},
+	{"other, websocket, more", true},
+}
+
+func TestTokenListContainsValue(t *testing.T) {
+	for _, tt := range tokenListContainsValueTests {
+		h := http.Header{"Upgrade": {tt.value}}
+		ok := tokenListContainsValue(h, "Upgrade", "websocket")
+		if ok != tt.ok {
+			t.Errorf("tokenListContainsValue(h, n, %q) = %v, want %v", tt.value, ok, tt.ok)
+		}
+	}
+}
+
+var isValidChallengeKeyTests = []struct {
+	key string
+	ok  bool
+}{
+	{"dGhlIHNhbXBsZSBub25jZQ==", true},
+	{"", false},
+	{"InvalidKey", false},
+	{"WHQ4eXhscUtKYjBvOGN3WEdtOEQ=", false},
+}
+
+func TestIsValidChallengeKey(t *testing.T) {
+	for _, tt := range isValidChallengeKeyTests {
+		ok := isValidChallengeKey(tt.key)
+		if ok != tt.ok {
+			t.Errorf("isValidChallengeKey returns %v, want %v", ok, tt.ok)
+		}
+	}
+}
+
+var parseExtensionTests = []struct {
+	value      string
+	extensions []map[string]string
+}{
+	{`foo`, []map[string]string{{"": "foo"}}},
+	{`foo, bar; baz=2`, []map[string]string{
+		{"": "foo"},
+		{"": "bar", "baz": "2"}}},
+	{`foo; bar="b,a;z"`, []map[string]string{
+		{"": "foo", "bar": "b,a;z"}}},
+	{`foo , bar; baz = 2`, []map[string]string{
+		{"": "foo"},
+		{"": "bar", "baz": "2"}}},
+	{`foo, bar; baz=2 junk`, []map[string]string{
+		{"": "foo"}}},
+	{`foo junk, bar; baz=2 junk`, nil},
+	{`mux; max-channels=4; flow-control, deflate-stream`, []map[string]string{
+		{"": "mux", "max-channels": "4", "flow-control": ""},
+		{"": "deflate-stream"}}},
+	{`permessage-foo; x="10"`, []map[string]string{
+		{"": "permessage-foo", "x": "10"}}},
+	{`permessage-foo; use_y, permessage-foo`, []map[string]string{
+		{"": "permessage-foo", "use_y": ""},
+		{"": "permessage-foo"}}},
+	{`permessage-deflate; client_max_window_bits; server_max_window_bits=10 , permessage-deflate; client_max_window_bits`, []map[string]string{
+		{"": "permessage-deflate", "client_max_window_bits": "", "server_max_window_bits": "10"},
+		{"": "permessage-deflate", "client_max_window_bits": ""}}},
+	{"permessage-deflate; server_no_context_takeover; client_max_window_bits=15", []map[string]string{
+		{"": "permessage-deflate", "server_no_context_takeover": "", "client_max_window_bits": "15"},
+	}},
+}
+
+func TestParseExtensions(t *testing.T) {
+	for _, tt := range parseExtensionTests {
+		h := http.Header{http.CanonicalHeaderKey("Sec-WebSocket-Extensions"): {tt.value}}
+		extensions := parseExtensions(h)
+		if !reflect.DeepEqual(extensions, tt.extensions) {
+			t.Errorf("parseExtensions(%q)\n    = %v,\nwant %v", tt.value, extensions, tt.extensions)
+		}
+	}
+}
+
+func TestParseArgs(t *testing.T) {
+	given := ParseArgs([]string { "x", "y", "z" })
+	expected := CLIArgs {
+		FromAddr: "y",
+		ToAddr:   "z",
+	}
+
+	g.AssertEqual(given, expected)
+}
+
+
+
+func MainTest() {
+	tests := []testing.InternalTest {
+		{ "TestProxyDial", TestProxyDial },
+		{ "TestProxyAuthorizationDial", TestProxyAuthorizationDial },
+		{ "TestDial", TestDial },
+		{ "TestDialCookieJar", TestDialCookieJar },
+		{ "TestDialTLS", TestDialTLS },
+		{ "TestDialTimeout", TestDialTimeout },
+		{ "TestHandshakeTimeout", TestHandshakeTimeout },
+		{ "TestHandshakeTimeoutInContext", TestHandshakeTimeoutInContext },
+		{ "TestDialBadScheme", TestDialBadScheme },
+		{ "TestDialBadOrigin", TestDialBadOrigin },
+		{ "TestDialBadHeader", TestDialBadHeader },
+		{ "TestBadMethod", TestBadMethod },
+		{ "TestNoUpgrade", TestNoUpgrade },
+		{ "TestDialExtraTokensInRespHeaders", TestDialExtraTokensInRespHeaders },
+		{ "TestHandshake", TestHandshake },
+		{ "TestRespOnBadHandshake", TestRespOnBadHandshake },
+		{ "TestHost", TestHost },
+		{ "TestDialCompression", TestDialCompression },
+		{ "TestSocksProxyDial", TestSocksProxyDial },
+		{ "TestTracingDialWithContext", TestTracingDialWithContext },
+		{ "TestEmptyTracingDialWithContext", TestEmptyTracingDialWithContext },
+		{ "TestNetDialConnect", TestNetDialConnect },
+		{ "TestNextProtos", TestNextProtos },
+		{ "TestDataReceivedBeforeHandshake", TestDataReceivedBeforeHandshake },
+		{ "TestHostPortNoPort", TestHostPortNoPort },
+		{ "TestTruncWriter", TestTruncWriter },
+		{ "TestValidCompressionLevel", TestValidCompressionLevel },
+		{ "TestFraming", TestFraming },
+		{ "TestWriteControlDeadline", TestWriteControlDeadline },
+		{ "TestConcurrencyWriteControl", TestConcurrencyWriteControl },
+		{ "TestControl", TestControl },
+		{ "TestWriteBufferPool", TestWriteBufferPool },
+		{ "TestWriteBufferPoolSync", TestWriteBufferPoolSync },
+		{ "TestWriteBufferPoolError", TestWriteBufferPoolError },
+		{ "TestCloseFrameBeforeFinalMessageFrame", TestCloseFrameBeforeFinalMessageFrame },
+		{ "TestEOFWithinFrame", TestEOFWithinFrame },
+		{ "TestEOFBeforeFinalFrame", TestEOFBeforeFinalFrame },
+		{ "TestWriteAfterMessageWriterClose", TestWriteAfterMessageWriterClose },
+		{ "TestReadLimit", TestReadLimit },
+		{ "TestAddrs", TestAddrs },
+		{ "TestDeprecatedUnderlyingConn", TestDeprecatedUnderlyingConn },
+		{ "TestNetConn", TestNetConn },
+		{ "TestBufioReadBytes", TestBufioReadBytes },
+		{ "TestCloseError", TestCloseError },
+		{ "TestUnexpectedCloseErrors", TestUnexpectedCloseErrors },
+		{ "TestConcurrentWritePanic", TestConcurrentWritePanic },
+		{ "TestFailedConnectionReadPanic", TestFailedConnectionReadPanic },
+		{ "TestJoinMessages", TestJoinMessages },
+		{ "TestJSON", TestJSON },
+		{ "TestPartialJSONRead", TestPartialJSONRead },
+		{ "TestDeprecatedJSON", TestDeprecatedJSON },
+		{ "TestMaskBytes", TestMaskBytes },
+		{ "TestPreparedMessage", TestPreparedMessage },
+		{ "TestSubprotocols", TestSubprotocols },
+		{ "TestIsWebSocketUpgrade", TestIsWebSocketUpgrade },
+		{ "TestSubProtocolSelection", TestSubProtocolSelection },
+		{ "TestCheckSameOrigin", TestCheckSameOrigin },
+		{ "TestHijack_NotSupported", TestHijack_NotSupported },
+		{ "TestEqualASCIIFold", TestEqualASCIIFold },
+		{ "TestTokenListContainsValue", TestTokenListContainsValue },
+		{ "TestIsValidChallengeKey", TestIsValidChallengeKey },
+		{ "TestParseExtensions", TestParseExtensions },
+		{ "TestParseArgs", TestParseArgs },
+	}
+
+	// FIXME: run benchmarks
+	benchmarks  := []testing.InternalBenchmark  {
+		{ "BenchmarkWriteNoCompression", BenchmarkWriteNoCompression },
+		{ "BenchmarkWriteWithCompression", BenchmarkWriteWithCompression },
+		{ "BenchmarkBroadcast", BenchmarkBroadcast },
+		{ "BenchmarkMaskBytes", BenchmarkMaskBytes },
+	}
+
+	fuzzTargets := []testing.InternalFuzzTarget {}
+	examples    := []testing.InternalExample    {}
+	m := testing.MainStart(
+		testdeps.TestDeps {},
+		tests,
+		benchmarks,
+		fuzzTargets,
+		examples,
+	)
+	os.Exit(m.Run())
+}