all: replace usages of whitelist/blacklist and master/slave

There's been plenty of discussion on the usage of these terms in tech.
I'm not trying to have yet another debate. It's clear that there are
people who are hurt by them and who are made to feel unwelcome by their
use due not to technical reasons but to their historical and social
context. That's simply enough reason to replace them.

Anyway, allowlist and blocklist are more self-explanatory than whitelist
and blacklist, so this change has negative cost.

Didn't change vendored, bundled, and minified files. Nearly all changes
are tests or comments, with a couple renames in cmd/link and cmd/oldlink
which are extremely safe. This should be fine to land during the freeze
without even asking for an exception.

Change-Id: I8fc54a3c8f9cc1973b710bbb9558a9e45810b896
Reviewed-on: https://go-review.googlesource.com/c/go/+/236857
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Khosrow Moossavi <khos2ow@gmail.com>
Reviewed-by: Leigh McCulloch <leighmcc@gmail.com>
Reviewed-by: Urban Ishimwe <urbainishimwe@gmail.com>
diff --git a/doc/go1.10.html b/doc/go1.10.html
index 41db36a..95871e0 100644
--- a/doc/go1.10.html
+++ b/doc/go1.10.html
@@ -30,7 +30,7 @@
 runs <a href="#test-vet">vet automatically during tests</a>,
 and
 permits <a href="#cgo">passing string values directly between Go and C using cgo</a>.
-A new <a href="#cgo">compiler option whitelist</a> may cause
+A new <a href="#cgo">hard-coded set of safe compiler options</a> may cause
 unexpected <a href="https://golang.org/s/invalidflag"><code>invalid
 flag</code></a> errors in code that built successfully with older
 releases.
@@ -267,7 +267,7 @@
 
 <p>
 Options specified by cgo using <code>#cgo CFLAGS</code> and the like
-are now checked against a whitelist of permitted options.
+are now checked against an allowlist of permitted options.
 This closes a security hole in which a downloaded package uses
 compiler options like
 <span style="white-space: nowrap"><code>-fplugin</code></span>
diff --git a/src/cmd/cgo/doc.go b/src/cmd/cgo/doc.go
index 4366df4..ca18c45 100644
--- a/src/cmd/cgo/doc.go
+++ b/src/cmd/cgo/doc.go
@@ -990,7 +990,7 @@
 linker in external linking mode.
 
 By default, cmd/link will decide the linking mode as follows: if the only
-packages using cgo are those on a whitelist of standard library
+packages using cgo are those on a list of known standard library
 packages (net, os/user, runtime/cgo), cmd/link will use internal linking
 mode. Otherwise, there are non-standard cgo packages involved, and cmd/link
 will use external linking mode. The first rule means that a build of
diff --git a/src/cmd/compile/fmt_test.go b/src/cmd/compile/fmt_test.go
index f1af647..768ca7f 100644
--- a/src/cmd/compile/fmt_test.go
+++ b/src/cmd/compile/fmt_test.go
@@ -96,7 +96,7 @@
 			}
 
 			importPath := filepath.Join("cmd/compile", path)
-			if blacklistedPackages[filepath.ToSlash(importPath)] {
+			if blocklistedPackages[filepath.ToSlash(importPath)] {
 				return filepath.SkipDir
 			}
 
@@ -344,8 +344,8 @@
 	for index, file := range files {
 		ast.Inspect(file, func(n ast.Node) bool {
 			if call, ok := n.(*ast.CallExpr); ok {
-				// ignore blacklisted functions
-				if blacklistedFunctions[nodeString(call.Fun)] {
+				// ignore blocklisted functions
+				if blocklistedFunctions[nodeString(call.Fun)] {
 					return true
 				}
 				// look for an arguments that might be a format string
@@ -354,7 +354,7 @@
 						// make sure we have enough arguments
 						n := numFormatArgs(s)
 						if i+1+n > len(call.Args) {
-							t.Errorf("%s: not enough format args (blacklist %s?)", posString(call), nodeString(call.Fun))
+							t.Errorf("%s: not enough format args (blocklist %s?)", posString(call), nodeString(call.Fun))
 							break // ignore this call
 						}
 						// assume last n arguments are to be formatted;
@@ -549,14 +549,14 @@
 	return string(append(buf, in[i0:]...))
 }
 
-// blacklistedPackages is the set of packages which can
+// blocklistedPackages is the set of packages which can
 // be ignored.
-var blacklistedPackages = map[string]bool{}
+var blocklistedPackages = map[string]bool{}
 
-// blacklistedFunctions is the set of functions which may have
+// blocklistedFunctions is the set of functions which may have
 // format-like arguments but which don't do any formatting and
 // thus may be ignored.
-var blacklistedFunctions = map[string]bool{}
+var blocklistedFunctions = map[string]bool{}
 
 func init() {
 	// verify that knownFormats entries are correctly formatted
diff --git a/src/cmd/compile/internal/gc/esc.go b/src/cmd/compile/internal/gc/esc.go
index 8e781a7..f3e9ab7 100644
--- a/src/cmd/compile/internal/gc/esc.go
+++ b/src/cmd/compile/internal/gc/esc.go
@@ -141,13 +141,13 @@
 	return samesafeexpr(dst.Left, src.Left)
 }
 
-// mayAffectMemory reports whether n evaluation may affect program memory state.
-// If expression can't affect it, then it can be safely ignored by the escape analysis.
+// mayAffectMemory reports whether evaluation of n may affect the program's
+// memory state. If the expression can't affect memory state, then it can be
+// safely ignored by the escape analysis.
 func mayAffectMemory(n *Node) bool {
-	// We may want to use "memory safe" black list instead of general
-	// "side-effect free", which can include all calls and other ops
-	// that can affect allocate or change global state.
-	// It's safer to start from a whitelist for now.
+	// We may want to use a list of "memory safe" ops instead of generally
+	// "side-effect free", which would include all calls and other ops that can
+	// allocate or change global state. For now, it's safer to start with the latter.
 	//
 	// We're ignoring things like division by zero, index out of range,
 	// and nil pointer dereference here.
diff --git a/src/cmd/go/internal/work/gc.go b/src/cmd/go/internal/work/gc.go
index 318d688..9a4fdcd 100644
--- a/src/cmd/go/internal/work/gc.go
+++ b/src/cmd/go/internal/work/gc.go
@@ -168,7 +168,7 @@
 CheckFlags:
 	for _, flag := range gcflags {
 		// Concurrent compilation is presumed incompatible with any gcflags,
-		// except for a small whitelist of commonly used flags.
+		// except for a small allowlist of commonly used flags.
 		// If the user knows better, they can manually add their own -c to the gcflags.
 		switch flag {
 		case "-N", "-l", "-S", "-B", "-C", "-I":
diff --git a/src/cmd/link/internal/loader/loader.go b/src/cmd/link/internal/loader/loader.go
index ab38bc3..b871f66 100644
--- a/src/cmd/link/internal/loader/loader.go
+++ b/src/cmd/link/internal/loader/loader.go
@@ -634,15 +634,15 @@
 	}
 	fmt.Fprintf(os.Stderr, "cmd/link: while reading object for '%v': duplicate symbol '%s', previous def at '%v', with mismatched payload: %s\n", r.unit.Lib, name, rdup.unit.Lib, reason)
 
-	// For the moment, whitelist DWARF subprogram DIEs for
+	// For the moment, allowlist DWARF subprogram DIEs for
 	// auto-generated wrapper functions. What seems to happen
 	// here is that we get different line numbers on formal
 	// params; I am guessing that the pos is being inherited
 	// from the spot where the wrapper is needed.
-	whitelist := strings.HasPrefix(name, "go.info.go.interface") ||
+	allowlist := strings.HasPrefix(name, "go.info.go.interface") ||
 		strings.HasPrefix(name, "go.info.go.builtin") ||
 		strings.HasPrefix(name, "go.debuglines")
-	if !whitelist {
+	if !allowlist {
 		l.strictDupMsgs++
 	}
 }
diff --git a/src/cmd/oldlink/internal/objfile/objfile.go b/src/cmd/oldlink/internal/objfile/objfile.go
index 6882b76..ae28e96 100644
--- a/src/cmd/oldlink/internal/objfile/objfile.go
+++ b/src/cmd/oldlink/internal/objfile/objfile.go
@@ -411,16 +411,16 @@
 			}
 			fmt.Fprintf(os.Stderr, "cmd/link: while reading object for '%v': duplicate symbol '%s', previous def at '%v', with mismatched payload: %s\n", r.lib, dup, dup.Unit.Lib, reason)
 
-			// For the moment, whitelist DWARF subprogram DIEs for
+			// For the moment, allowlist DWARF subprogram DIEs for
 			// auto-generated wrapper functions. What seems to happen
 			// here is that we get different line numbers on formal
 			// params; I am guessing that the pos is being inherited
 			// from the spot where the wrapper is needed.
-			whitelist := (strings.HasPrefix(dup.Name, "go.info.go.interface") ||
+			allowlist := (strings.HasPrefix(dup.Name, "go.info.go.interface") ||
 				strings.HasPrefix(dup.Name, "go.info.go.builtin") ||
 				strings.HasPrefix(dup.Name, "go.isstmt.go.builtin") ||
 				strings.HasPrefix(dup.Name, "go.debuglines"))
-			if !whitelist {
+			if !allowlist {
 				r.strictDupMsgs++
 			}
 		}
diff --git a/src/html/template/html.go b/src/html/template/html.go
index 13a0cd0..d3359ca 100644
--- a/src/html/template/html.go
+++ b/src/html/template/html.go
@@ -240,7 +240,7 @@
 	}
 	s = strings.ToLower(s)
 	if t := attrType(s); t != contentTypePlain {
-		// TODO: Split attr and element name part filters so we can whitelist
+		// TODO: Split attr and element name part filters so we can allowlist
 		// attributes.
 		return filterFailsafe
 	}
diff --git a/src/net/http/request.go b/src/net/http/request.go
index e924e2a..e4a00dd 100644
--- a/src/net/http/request.go
+++ b/src/net/http/request.go
@@ -503,7 +503,7 @@
 
 // NOTE: This is not intended to reflect the actual Go version being used.
 // It was changed at the time of Go 1.1 release because the former User-Agent
-// had ended up on a blacklist for some intrusion detection systems.
+// had ended up on a blocklist for some intrusion detection systems.
 // See https://codereview.appspot.com/7532043.
 const defaultUserAgent = "Go-http-client/1.1"
 
diff --git a/src/net/http/server.go b/src/net/http/server.go
index b613c21..a75dd14 100644
--- a/src/net/http/server.go
+++ b/src/net/http/server.go
@@ -1698,8 +1698,8 @@
 	time.Sleep(rstAvoidanceDelay)
 }
 
-// validNextProto reports whether the proto is not a blacklisted ALPN
-// protocol name. Empty and built-in protocol types are blacklisted
+// validNextProto reports whether the proto is not a blocklisted ALPN
+// protocol name. Empty and built-in protocol types are blocklisted
 // and can't be overridden with alternate implementations.
 func validNextProto(proto string) bool {
 	switch proto {
diff --git a/src/os/signal/internal/pty/pty.go b/src/os/signal/internal/pty/pty.go
index fb3ee1e..f8813ce 100644
--- a/src/os/signal/internal/pty/pty.go
+++ b/src/os/signal/internal/pty/pty.go
@@ -40,8 +40,8 @@
 
 func (e *PtyError) Unwrap() error { return e.Errno }
 
-// Open returns a master pty and the name of the linked slave tty.
-func Open() (master *os.File, slave string, err error) {
+// Open returns a control pty and the name of the linked process tty.
+func Open() (pty *os.File, processTTY string, err error) {
 	m, err := C.posix_openpt(C.O_RDWR)
 	if err != nil {
 		return nil, "", ptyError("posix_openpt", err)
@@ -54,6 +54,6 @@
 		C.close(m)
 		return nil, "", ptyError("unlockpt", err)
 	}
-	slave = C.GoString(C.ptsname(m))
-	return os.NewFile(uintptr(m), "pty-master"), slave, nil
+	processTTY = C.GoString(C.ptsname(m))
+	return os.NewFile(uintptr(m), "pty"), processTTY, nil
 }
diff --git a/src/os/signal/signal_cgo_test.go b/src/os/signal/signal_cgo_test.go
index 849a96e..a117221 100644
--- a/src/os/signal/signal_cgo_test.go
+++ b/src/os/signal/signal_cgo_test.go
@@ -19,7 +19,7 @@
 	"io"
 	"os"
 	"os/exec"
-	"os/signal/internal/pty"
+	ptypkg "os/signal/internal/pty"
 	"strconv"
 	"strings"
 	"sync"
@@ -71,20 +71,20 @@
 	// The test only fails when using a "slow device," in this
 	// case a pseudo-terminal.
 
-	master, sname, err := pty.Open()
+	pty, procTTYName, err := ptypkg.Open()
 	if err != nil {
-		ptyErr := err.(*pty.PtyError)
+		ptyErr := err.(*ptypkg.PtyError)
 		if ptyErr.FuncName == "posix_openpt" && ptyErr.Errno == syscall.EACCES {
 			t.Skip("posix_openpt failed with EACCES, assuming chroot and skipping")
 		}
 		t.Fatal(err)
 	}
-	defer master.Close()
-	slave, err := os.OpenFile(sname, os.O_RDWR, 0)
+	defer pty.Close()
+	procTTY, err := os.OpenFile(procTTYName, os.O_RDWR, 0)
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer slave.Close()
+	defer procTTY.Close()
 
 	// Start an interactive shell.
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
@@ -92,9 +92,9 @@
 	cmd := exec.CommandContext(ctx, bash, "--norc", "--noprofile", "-i")
 	// Clear HISTFILE so that we don't read or clobber the user's bash history.
 	cmd.Env = append(os.Environ(), "HISTFILE=")
-	cmd.Stdin = slave
-	cmd.Stdout = slave
-	cmd.Stderr = slave
+	cmd.Stdin = procTTY
+	cmd.Stdout = procTTY
+	cmd.Stderr = procTTY
 	cmd.SysProcAttr = &syscall.SysProcAttr{
 		Setsid:  true,
 		Setctty: true,
@@ -105,21 +105,21 @@
 		t.Fatal(err)
 	}
 
-	if err := slave.Close(); err != nil {
-		t.Errorf("closing slave: %v", err)
+	if err := procTTY.Close(); err != nil {
+		t.Errorf("closing procTTY: %v", err)
 	}
 
 	progReady := make(chan bool)
 	sawPrompt := make(chan bool, 10)
 	const prompt = "prompt> "
 
-	// Read data from master in the background.
+	// Read data from pty in the background.
 	var wg sync.WaitGroup
 	wg.Add(1)
 	defer wg.Wait()
 	go func() {
 		defer wg.Done()
-		input := bufio.NewReader(master)
+		input := bufio.NewReader(pty)
 		var line, handled []byte
 		for {
 			b, err := input.ReadByte()
@@ -130,11 +130,11 @@
 				if perr, ok := err.(*os.PathError); ok {
 					err = perr.Err
 				}
-				// EOF means master is closed.
+				// EOF means pty is closed.
 				// EIO means child process is done.
-				// "file already closed" means deferred close of master has happened.
+				// "file already closed" means deferred close of pty has happened.
 				if err != io.EOF && err != syscall.EIO && !strings.Contains(err.Error(), "file already closed") {
-					t.Logf("error reading from master: %v", err)
+					t.Logf("error reading from pty: %v", err)
 				}
 				return
 			}
@@ -161,7 +161,7 @@
 	}()
 
 	// Set the bash prompt so that we can see it.
-	if _, err := master.Write([]byte("PS1='" + prompt + "'\n")); err != nil {
+	if _, err := pty.Write([]byte("PS1='" + prompt + "'\n")); err != nil {
 		t.Fatalf("setting prompt: %v", err)
 	}
 	select {
@@ -172,7 +172,7 @@
 
 	// Start a small program that reads from stdin
 	// (namely the code at the top of this function).
-	if _, err := master.Write([]byte("GO_TEST_TERMINAL_SIGNALS=1 " + os.Args[0] + " -test.run=TestTerminalSignal\n")); err != nil {
+	if _, err := pty.Write([]byte("GO_TEST_TERMINAL_SIGNALS=1 " + os.Args[0] + " -test.run=TestTerminalSignal\n")); err != nil {
 		t.Fatal(err)
 	}
 
@@ -190,7 +190,7 @@
 	time.Sleep(pause)
 
 	// Send a ^Z to stop the program.
-	if _, err := master.Write([]byte{26}); err != nil {
+	if _, err := pty.Write([]byte{26}); err != nil {
 		t.Fatalf("writing ^Z to pty: %v", err)
 	}
 
@@ -202,7 +202,7 @@
 	}
 
 	// Restart the stopped program.
-	if _, err := master.Write([]byte("fg\n")); err != nil {
+	if _, err := pty.Write([]byte("fg\n")); err != nil {
 		t.Fatalf("writing %q to pty: %v", "fg", err)
 	}
 
@@ -217,7 +217,7 @@
 
 	// Write some data for the program to read,
 	// which should cause it to exit.
-	if _, err := master.Write([]byte{'\n'}); err != nil {
+	if _, err := pty.Write([]byte{'\n'}); err != nil {
 		t.Fatalf("writing %q to pty: %v", "\n", err)
 	}
 
@@ -229,7 +229,7 @@
 	}
 
 	// Exit the shell with the program's exit status.
-	if _, err := master.Write([]byte("exit $?\n")); err != nil {
+	if _, err := pty.Write([]byte("exit $?\n")); err != nil {
 		t.Fatalf("writing %q to pty: %v", "exit", err)
 	}
 
diff --git a/src/runtime/cgo_sigaction.go b/src/runtime/cgo_sigaction.go
index bc5e078..967b8b9 100644
--- a/src/runtime/cgo_sigaction.go
+++ b/src/runtime/cgo_sigaction.go
@@ -18,7 +18,7 @@
 //go:nosplit
 //go:nowritebarrierrec
 func sigaction(sig uint32, new, old *sigactiont) {
-	// The runtime package is explicitly blacklisted from sanitizer
+	// The runtime package is explicitly blocklisted from sanitizer
 	// instrumentation in racewalk.go, but we might be calling into instrumented C
 	// functions here — so we need the pointer parameters to be properly marked.
 	//
diff --git a/src/runtime/debugcall.go b/src/runtime/debugcall.go
index 5cbe382..496e6ce 100644
--- a/src/runtime/debugcall.go
+++ b/src/runtime/debugcall.go
@@ -61,7 +61,7 @@
 			"debugCall16384",
 			"debugCall32768",
 			"debugCall65536":
-			// These functions are whitelisted so that the debugger can initiate multiple function calls.
+			// These functions are allowlisted so that the debugger can initiate multiple function calls.
 			// See: https://golang.org/cl/161137/
 			return
 		}