all: Remove lib/util package (#9049)

Grab-bag packages are nasty, this cleans it up a little by splitting it
into topical packages sempahore, netutil, stringutil, structutil.

lib/api/api_test.go

@@ -44,8 +44,8 @@ import (
 	"github.com/syncthing/syncthing/lib/sync"
 	"github.com/syncthing/syncthing/lib/tlsutil"
 	"github.com/syncthing/syncthing/lib/ur"
-	"github.com/syncthing/syncthing/lib/util"
 	"github.com/thejerf/suture/v4"
+	"golang.org/x/exp/slices"
 )
 
 var (
@@ -1313,7 +1313,7 @@ func TestBrowse(t *testing.T) {
 
 	for _, tc := range cases {
 		ret := browseFiles(ffs, tc.current)
-		if !util.EqualStrings(ret, tc.returns) {
+		if !slices.Equal(ret, tc.returns) {
 			t.Errorf("browseFiles(%q) => %q, expected %q", tc.current, ret, tc.returns)
 		}
 	}

lib/api/confighandler.go

@@ -15,7 +15,7 @@ import (
 
 	"github.com/syncthing/syncthing/lib/config"
 	"github.com/syncthing/syncthing/lib/protocol"
-	"github.com/syncthing/syncthing/lib/util"
+	"github.com/syncthing/syncthing/lib/structutil"
 )
 
 type configMuxBuilder struct {
@@ -212,7 +212,7 @@ func (c *configMuxBuilder) registerDefaultFolder(path string) {
 
 	c.HandlerFunc(http.MethodPut, path, func(w http.ResponseWriter, r *http.Request) {
 		var cfg config.FolderConfiguration
-		util.SetDefaults(&cfg)
+		structutil.SetDefaults(&cfg)
 		c.adjustFolder(w, r, cfg, true)
 	})
 
@@ -228,7 +228,7 @@ func (c *configMuxBuilder) registerDefaultDevice(path string) {
 
 	c.HandlerFunc(http.MethodPut, path, func(w http.ResponseWriter, r *http.Request) {
 		var cfg config.DeviceConfiguration
-		util.SetDefaults(&cfg)
+		structutil.SetDefaults(&cfg)
 		c.adjustDevice(w, r, cfg, true)
 	})
 
@@ -266,7 +266,7 @@ func (c *configMuxBuilder) registerOptions(path string) {
 
 	c.HandlerFunc(http.MethodPut, path, func(w http.ResponseWriter, r *http.Request) {
 		var cfg config.OptionsConfiguration
-		util.SetDefaults(&cfg)
+		structutil.SetDefaults(&cfg)
 		c.adjustOptions(w, r, cfg)
 	})
 
@@ -282,7 +282,7 @@ func (c *configMuxBuilder) registerLDAP(path string) {
 
 	c.HandlerFunc(http.MethodPut, path, func(w http.ResponseWriter, r *http.Request) {
 		var cfg config.LDAPConfiguration
-		util.SetDefaults(&cfg)
+		structutil.SetDefaults(&cfg)
 		c.adjustLDAP(w, r, cfg)
 	})
 
@@ -298,7 +298,7 @@ func (c *configMuxBuilder) registerGUI(path string) {
 
 	c.HandlerFunc(http.MethodPut, path, func(w http.ResponseWriter, r *http.Request) {
 		var cfg config.GUIConfiguration
-		util.SetDefaults(&cfg)
+		structutil.SetDefaults(&cfg)
 		c.adjustGUI(w, r, cfg)
 	})
 

lib/config/config.go

@@ -16,14 +16,16 @@ import (
 	"net"
 	"net/url"
 	"os"
+	"reflect"
 	"sort"
 	"strconv"
 	"strings"
 
 	"github.com/syncthing/syncthing/lib/build"
 	"github.com/syncthing/syncthing/lib/fs"
+	"github.com/syncthing/syncthing/lib/netutil"
 	"github.com/syncthing/syncthing/lib/protocol"
-	"github.com/syncthing/syncthing/lib/util"
+	"github.com/syncthing/syncthing/lib/structutil"
 )
 
 const (
@@ -42,9 +44,9 @@ var (
 	// "consumer" of the configuration as we don't want these saved to the
 	// config.
 	DefaultListenAddresses = []string{
-		util.Address("tcp", net.JoinHostPort("0.0.0.0", strconv.Itoa(DefaultTCPPort))),
+		netutil.AddressURL("tcp", net.JoinHostPort("0.0.0.0", strconv.Itoa(DefaultTCPPort))),
 		"dynamic+https://relays.syncthing.net/endpoint",
-		util.Address("quic", net.JoinHostPort("0.0.0.0", strconv.Itoa(DefaultQUICPort))),
+		netutil.AddressURL("quic", net.JoinHostPort("0.0.0.0", strconv.Itoa(DefaultQUICPort))),
 	}
 	DefaultGUIPort = 8384
 	// DefaultDiscoveryServersV4 should be substituted when the configuration
@@ -101,7 +103,7 @@ func New(myID protocol.DeviceID) Configuration {
 
 	cfg.Options.UnackedNotificationIDs = []string{"authenticationUserAndPassword"}
 
-	util.SetDefaults(&cfg)
+	structutil.SetDefaults(&cfg)
 
 	// Can't happen.
 	if err := cfg.prepare(myID); err != nil {
@@ -127,9 +129,9 @@ func (cfg *Configuration) ProbeFreePorts() error {
 		cfg.Options.RawListenAddresses = []string{"default"}
 	} else {
 		cfg.Options.RawListenAddresses = []string{
-			util.Address("tcp", net.JoinHostPort("0.0.0.0", strconv.Itoa(port))),
+			netutil.AddressURL("tcp", net.JoinHostPort("0.0.0.0", strconv.Itoa(port))),
 			"dynamic+https://relays.syncthing.net/endpoint",
-			util.Address("quic", net.JoinHostPort("0.0.0.0", strconv.Itoa(port))),
+			netutil.AddressURL("quic", net.JoinHostPort("0.0.0.0", strconv.Itoa(port))),
 		}
 	}
 
@@ -144,7 +146,7 @@ type xmlConfiguration struct {
 func ReadXML(r io.Reader, myID protocol.DeviceID) (Configuration, int, error) {
 	var cfg xmlConfiguration
 
-	util.SetDefaults(&cfg)
+	structutil.SetDefaults(&cfg)
 
 	if err := xml.NewDecoder(r).Decode(&cfg); err != nil {
 		return Configuration{}, 0, err
@@ -166,7 +168,7 @@ func ReadJSON(r io.Reader, myID protocol.DeviceID) (Configuration, error) {
 
 	var cfg Configuration
 
-	util.SetDefaults(&cfg)
+	structutil.SetDefaults(&cfg)
 
 	if err := json.Unmarshal(bs, &cfg); err != nil {
 		return Configuration{}, err
@@ -259,7 +261,7 @@ func (cfg *Configuration) prepare(myID protocol.DeviceID) error {
 
 	cfg.removeDeprecatedProtocols()
 
-	util.FillNilExceptDeprecated(cfg)
+	structutil.FillNilExceptDeprecated(cfg)
 
 	// TestIssue1750 relies on migrations happening after preparing options.
 	cfg.applyMigrations()
@@ -636,14 +638,44 @@ func (defaults *Defaults) prepare(myID protocol.DeviceID, existingDevices map[pr
 }
 
 func ensureZeroForNodefault(empty interface{}, target interface{}) {
-	util.CopyMatchingTag(empty, target, "nodefault", func(v string) bool {
+	copyMatchingTag(empty, target, "nodefault", func(v string) bool {
 		if len(v) > 0 && v != "true" {
 			panic(fmt.Sprintf(`unexpected tag value: %s. expected untagged or "true"`, v))
 		}
 		return len(v) > 0
 	})
 }
 
+// copyMatchingTag copies fields tagged tag:"value" from "from" struct onto "to" struct.
+func copyMatchingTag(from interface{}, to interface{}, tag string, shouldCopy func(value string) bool) {
+	fromStruct := reflect.ValueOf(from).Elem()
+	fromType := fromStruct.Type()
+
+	toStruct := reflect.ValueOf(to).Elem()
+	toType := toStruct.Type()
+
+	if fromType != toType {
+		panic(fmt.Sprintf("non equal types: %s != %s", fromType, toType))
+	}
+
+	for i := 0; i < toStruct.NumField(); i++ {
+		fromField := fromStruct.Field(i)
+		toField := toStruct.Field(i)
+
+		if !toField.CanSet() {
+			// Unexported fields
+			continue
+		}
+
+		structTag := toType.Field(i).Tag
+
+		v := structTag.Get(tag)
+		if shouldCopy(v) {
+			toField.Set(fromField)
+		}
+	}
+}
+
 func (i Ignores) Copy() Ignores {
 	out := Ignores{Lines: make([]string, len(i.Lines))}
 	copy(out.Lines, i.Lines)

lib/config/config_test.go

@@ -1597,3 +1597,61 @@ func handleFile(name string) {
 	fd.Write(origin)
 	fd.Close()
 }
+
+func TestCopyMatching(t *testing.T) {
+	type Nested struct {
+		A int
+	}
+	type Test struct {
+		CopyA  int
+		CopyB  []string
+		CopyC  Nested
+		CopyD  *Nested
+		NoCopy int `restart:"true"`
+	}
+
+	from := Test{
+		CopyA: 1,
+		CopyB: []string{"friend", "foe"},
+		CopyC: Nested{
+			A: 2,
+		},
+		CopyD: &Nested{
+			A: 3,
+		},
+		NoCopy: 4,
+	}
+
+	to := Test{
+		CopyA: 11,
+		CopyB: []string{"foot", "toe"},
+		CopyC: Nested{
+			A: 22,
+		},
+		CopyD: &Nested{
+			A: 33,
+		},
+		NoCopy: 44,
+	}
+
+	// Copy empty fields
+	copyMatchingTag(&from, &to, "restart", func(v string) bool {
+		return v != "true"
+	})
+
+	if to.CopyA != 1 {
+		t.Error("CopyA")
+	}
+	if len(to.CopyB) != 2 || to.CopyB[0] != "friend" || to.CopyB[1] != "foe" {
+		t.Error("CopyB")
+	}
+	if to.CopyC.A != 2 {
+		t.Error("CopyC")
+	}
+	if to.CopyD.A != 3 {
+		t.Error("CopyC")
+	}
+	if to.NoCopy != 44 {
+		t.Error("NoCopy")
+	}
+}

lib/config/folderconfiguration.go

@@ -21,7 +21,6 @@ import (
 	"github.com/syncthing/syncthing/lib/db"
 	"github.com/syncthing/syncthing/lib/fs"
 	"github.com/syncthing/syncthing/lib/protocol"
-	"github.com/syncthing/syncthing/lib/util"
 )
 
 var (
@@ -244,7 +243,7 @@ func (f FolderConfiguration) RequiresRestartOnly() FolderConfiguration {
 	// copier, yet should not cause a restart.
 
 	blank := FolderConfiguration{}
-	util.CopyMatchingTag(&blank, &copy, "restart", func(v string) bool {
+	copyMatchingTag(&blank, &copy, "restart", func(v string) bool {
 		if len(v) > 0 && v != "false" {
 			panic(fmt.Sprintf(`unexpected tag value: %s. expected untagged or "false"`, v))
 		}

lib/config/migrations.go

@@ -17,8 +17,8 @@ import (
 
 	"github.com/syncthing/syncthing/lib/build"
 	"github.com/syncthing/syncthing/lib/fs"
+	"github.com/syncthing/syncthing/lib/netutil"
 	"github.com/syncthing/syncthing/lib/upgrade"
-	"github.com/syncthing/syncthing/lib/util"
 )
 
 // migrations is the set of config migration functions, with their target
@@ -197,11 +197,11 @@ func migrateToConfigV24(cfg *Configuration) {
 }
 
 func migrateToConfigV23(cfg *Configuration) {
-	permBits := fs.FileMode(0777)
+	permBits := fs.FileMode(0o777)
 	if build.IsWindows {
 		// Windows has no umask so we must chose a safer set of bits to
 		// begin with.
-		permBits = 0700
+		permBits = 0o700
 	}
 
 	// Upgrade code remains hardcoded for .stfolder despite configurable
@@ -391,14 +391,14 @@ func migrateToConfigV12(cfg *Configuration) {
 	// Change listen address schema
 	for i, addr := range cfg.Options.RawListenAddresses {
 		if len(addr) > 0 && !strings.HasPrefix(addr, "tcp://") {
-			cfg.Options.RawListenAddresses[i] = util.Address("tcp", addr)
+			cfg.Options.RawListenAddresses[i] = netutil.AddressURL("tcp", addr)
 		}
 	}
 
 	for i, device := range cfg.Devices {
 		for j, addr := range device.Addresses {
 			if addr != "dynamic" && addr != "" {
-				cfg.Devices[i].Addresses[j] = util.Address("tcp", addr)
+				cfg.Devices[i].Addresses[j] = netutil.AddressURL("tcp", addr)
 			}
 		}
 	}

lib/config/optionsconfiguration.go

@@ -12,7 +12,8 @@ import (
 
 	"github.com/syncthing/syncthing/lib/protocol"
 	"github.com/syncthing/syncthing/lib/rand"
-	"github.com/syncthing/syncthing/lib/util"
+	"github.com/syncthing/syncthing/lib/stringutil"
+	"github.com/syncthing/syncthing/lib/structutil"
 )
 
 func (opts OptionsConfiguration) Copy() OptionsConfiguration {
@@ -29,10 +30,10 @@ func (opts OptionsConfiguration) Copy() OptionsConfiguration {
 }
 
 func (opts *OptionsConfiguration) prepare(guiPWIsSet bool) {
-	util.FillNilSlices(opts)
+	structutil.FillNilSlices(opts)
 
-	opts.RawListenAddresses = util.UniqueTrimmedStrings(opts.RawListenAddresses)
-	opts.RawGlobalAnnServers = util.UniqueTrimmedStrings(opts.RawGlobalAnnServers)
+	opts.RawListenAddresses = stringutil.UniqueTrimmedStrings(opts.RawListenAddresses)
+	opts.RawGlobalAnnServers = stringutil.UniqueTrimmedStrings(opts.RawGlobalAnnServers)
 
 	// Very short reconnection intervals are annoying
 	if opts.ReconnectIntervalS < 5 {
@@ -71,7 +72,7 @@ func (opts *OptionsConfiguration) prepare(guiPWIsSet bool) {
 func (opts OptionsConfiguration) RequiresRestartOnly() OptionsConfiguration {
 	optsCopy := opts
 	blank := OptionsConfiguration{}
-	util.CopyMatchingTag(&blank, &optsCopy, "restart", func(v string) bool {
+	copyMatchingTag(&blank, &optsCopy, "restart", func(v string) bool {
 		if len(v) > 0 && v != "true" {
 			panic(fmt.Sprintf(`unexpected tag value: %s. Expected untagged or "true"`, v))
 		}
@@ -94,7 +95,7 @@ func (opts OptionsConfiguration) ListenAddresses() []string {
 			addresses = append(addresses, addr)
 		}
 	}
-	return util.UniqueTrimmedStrings(addresses)
+	return stringutil.UniqueTrimmedStrings(addresses)
 }
 
 func (opts OptionsConfiguration) StunServers() []string {
@@ -116,7 +117,7 @@ func (opts OptionsConfiguration) StunServers() []string {
 		}
 	}
 
-	addresses = util.UniqueTrimmedStrings(addresses)
+	addresses = stringutil.UniqueTrimmedStrings(addresses)
 
 	return addresses
 }
@@ -135,7 +136,7 @@ func (opts OptionsConfiguration) GlobalDiscoveryServers() []string {
 			servers = append(servers, srv)
 		}
 	}
-	return util.UniqueTrimmedStrings(servers)
+	return stringutil.UniqueTrimmedStrings(servers)
 }
 
 func (opts OptionsConfiguration) MaxFolderConcurrency() int {

lib/config/size_test.go

@@ -10,7 +10,7 @@ import (
 	"testing"
 
 	"github.com/syncthing/syncthing/lib/fs"
-	"github.com/syncthing/syncthing/lib/util"
+	"github.com/syncthing/syncthing/lib/structutil"
 )
 
 type TestStruct struct {
@@ -20,7 +20,7 @@ type TestStruct struct {
 func TestSizeDefaults(t *testing.T) {
 	x := &TestStruct{}
 
-	util.SetDefaults(x)
+	structutil.SetDefaults(x)
 
 	if !x.Size.Percentage() {
 		t.Error("not percentage")