util/syspolicy: remove handler, other dead code

Fixes #17022

Change-Id: I6a0f6488ae3ea75c5844dfcba68e1e8024e930be
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

util/syspolicy/handler.go

@@ -1,99 +0,0 @@
-// Copyright (c) Tailscale Inc & AUTHORS
-// SPDX-License-Identifier: BSD-3-Clause
-
-package syspolicy
-
-import (
-	"tailscale.com/util/syspolicy/pkey"
-	"tailscale.com/util/syspolicy/rsop"
-	"tailscale.com/util/syspolicy/setting"
-	"tailscale.com/util/syspolicy/source"
-)
-
-// TODO(nickkhyl): delete this file once other repos are updated.
-
-// Handler reads system policies from OS-specific storage.
-//
-// Deprecated: implementing a [source.Store] should be preferred.
-type Handler interface {
-	// ReadString reads the policy setting's string value for the given key.
-	// It should return ErrNoSuchKey if the key does not have a value set.
-	ReadString(key string) (string, error)
-	// ReadUInt64 reads the policy setting's uint64 value for the given key.
-	// It should return ErrNoSuchKey if the key does not have a value set.
-	ReadUInt64(key string) (uint64, error)
-	// ReadBool reads the policy setting's boolean value for the given key.
-	// It should return ErrNoSuchKey if the key does not have a value set.
-	ReadBoolean(key string) (bool, error)
-	// ReadStringArray reads the policy setting's string array value for the given key.
-	// It should return ErrNoSuchKey if the key does not have a value set.
-	ReadStringArray(key string) ([]string, error)
-}
-
-// RegisterHandler wraps and registers the specified handler as the device's
-// policy [source.Store] for the program's lifetime.
-//
-// Deprecated: using [RegisterStore] should be preferred.
-func RegisterHandler(h Handler) {
-	rsop.RegisterStore("DeviceHandler", setting.DeviceScope, handlerStore{h})
-}
-
-var _ source.Store = handlerStore{}
-
-// handlerStore is a [source.Store] that calls the underlying [Handler].
-//
-// TODO(nickkhyl): remove it when the corp and android repos are updated.
-type handlerStore struct {
-	h Handler
-}
-
-// Lock implements [source.Lockable].
-func (s handlerStore) Lock() error {
-	if lockable, ok := s.h.(source.Lockable); ok {
-		return lockable.Lock()
-	}
-	return nil
-}
-
-// Unlock implements [source.Lockable].
-func (s handlerStore) Unlock() {
-	if lockable, ok := s.h.(source.Lockable); ok {
-		lockable.Unlock()
-	}
-}
-
-// RegisterChangeCallback implements [source.Changeable].
-func (s handlerStore) RegisterChangeCallback(callback func()) (unregister func(), err error) {
-	if changeable, ok := s.h.(source.Changeable); ok {
-		return changeable.RegisterChangeCallback(callback)
-	}
-	return func() {}, nil
-}
-
-// ReadString implements [source.Store].
-func (s handlerStore) ReadString(key pkey.Key) (string, error) {
-	return s.h.ReadString(string(key))
-}
-
-// ReadUInt64 implements [source.Store].
-func (s handlerStore) ReadUInt64(key pkey.Key) (uint64, error) {
-	return s.h.ReadUInt64(string(key))
-}
-
-// ReadBoolean implements [source.Store].
-func (s handlerStore) ReadBoolean(key pkey.Key) (bool, error) {
-	return s.h.ReadBoolean(string(key))
-}
-
-// ReadStringArray implements [source.Store].
-func (s handlerStore) ReadStringArray(key pkey.Key) ([]string, error) {
-	return s.h.ReadStringArray(string(key))
-}
-
-// Done implements [source.Expirable].
-func (s handlerStore) Done() <-chan struct{} {
-	if expirable, ok := s.h.(source.Expirable); ok {
-		return expirable.Done()
-	}
-	return nil
-}

util/syspolicy/policy_keys.go

@@ -4,7 +4,6 @@
 package syspolicy
 
 import (
-	"tailscale.com/types/lazy"
 	"tailscale.com/util/syspolicy/internal"
 	"tailscale.com/util/syspolicy/pkey"
 	"tailscale.com/util/syspolicy/setting"
@@ -78,24 +77,6 @@ func init() {
 	})
 }
 
-var implicitDefinitionMap lazy.SyncValue[setting.DefinitionMap]
-
-// WellKnownSettingDefinition returns a well-known, implicit setting definition by its key,
-// or an [ErrNoSuchKey] if a policy setting with the specified key does not exist
-// among implicit policy definitions.
-func WellKnownSettingDefinition(k pkey.Key) (*setting.Definition, error) {
-	m, err := implicitDefinitionMap.GetErr(func() (setting.DefinitionMap, error) {
-		return setting.DefinitionMapOf(implicitDefinitions)
-	})
-	if err != nil {
-		return nil, err
-	}
-	if d, ok := m[k]; ok {
-		return d, nil
-	}
-	return nil, ErrNoSuchKey
-}
-
 // RegisterWellKnownSettingsForTest registers all implicit setting definitions
 // for the duration of the test.
 func RegisterWellKnownSettingsForTest(tb testenv.TB) {

util/syspolicy/policy_keys_test.go

@@ -46,13 +46,6 @@ func TestKnownKeysRegistered(t *testing.T) {
 	}
 }
 
-func TestNotAWellKnownSetting(t *testing.T) {
-	d, err := WellKnownSettingDefinition("TestSettingDoesNotExist")
-	if d != nil || err == nil {
-		t.Fatalf("got %v, %v; want nil, %v", d, err, ErrNoSuchKey)
-	}
-}
-
 func listStringConsts[T ~string](filename string) (map[string]T, error) {
 	fset := token.NewFileSet()
 	src, err := os.ReadFile(filename)