hst/dbus: move dbus config struct

This allows holding a xdg-dbus-proxy configuration without importing system/dbus.

It also makes more sense in the project structure since the config struct is part of the hst API however the rest of the implementation is not.

Signed-off-by: Ophestra <cat@gensokyo.uk>

system/dbus/config.go

@@ -1,64 +1,50 @@
 package dbus
 
 import (
-	"encoding/json"
-	"errors"
-	"io"
-	"os"
 	"strings"
+
+	"hakurei.app/hst"
 )
 
 // ProxyPair is an upstream dbus address and a downstream socket path.
 type ProxyPair [2]string
 
-type Config struct {
-	// See set 'see' policy for NAME (--see=NAME)
-	See []string `json:"see"`
-	// Talk set 'talk' policy for NAME (--talk=NAME)
-	Talk []string `json:"talk"`
-	// Own set 'own' policy for NAME (--own=NAME)
-	Own []string `json:"own"`
-
-	// Call set RULE for calls on NAME (--call=NAME=RULE)
-	Call map[string]string `json:"call"`
-	// Broadcast set RULE for broadcasts from NAME (--broadcast=NAME=RULE)
-	Broadcast map[string]string `json:"broadcast"`
-
-	Log    bool `json:"log,omitempty"`
-	Filter bool `json:"filter"`
-}
-
-func (c *Config) interfaces(yield func(string) bool) {
-	for _, iface := range c.See {
-		if !yield(iface) {
-			return
+// interfacesAll returns an iterator over all interfaces specified in c.
+func interfacesAll(c *hst.BusConfig) func(yield func(string) bool) {
+	return func(yield func(string) bool) {
+		for _, iface := range c.See {
+			if !yield(iface) {
+				return
+			}
 		}
-	}
-	for _, iface := range c.Talk {
-		if !yield(iface) {
-			return
+		for _, iface := range c.Talk {
+			if !yield(iface) {
+				return
+			}
 		}
-	}
-	for _, iface := range c.Own {
-		if !yield(iface) {
-			return
+		for _, iface := range c.Own {
+			if !yield(iface) {
+				return
+			}
 		}
-	}
 
-	for iface := range c.Call {
-		if !yield(iface) {
-			return
+		for iface := range c.Call {
+			if !yield(iface) {
+				return
+			}
 		}
-	}
-	for iface := range c.Broadcast {
-		if !yield(iface) {
-			return
+		for iface := range c.Broadcast {
+			if !yield(iface) {
+				return
+			}
 		}
 	}
 }
 
-func (c *Config) checkInterfaces(segment string) error {
-	for iface := range c.interfaces {
+// checkInterfaces checks [hst.BusConfig] for invalid interfaces based on an undocumented check in xdg-dbus-error,
+// returning [BadInterfaceError] if one is encountered.
+func checkInterfaces(c *hst.BusConfig, segment string) error {
+	for iface := range interfacesAll(c) {
 		/*
 			xdg-dbus-proxy fails without output when this condition is not met:
 				char *dot = strrchr (filter->interface, '.');
@@ -83,7 +69,8 @@ func (c *Config) checkInterfaces(segment string) error {
 	return nil
 }
 
-func (c *Config) Args(bus ProxyPair) (args []string) {
+// Args returns the xdg-dbus-proxy arguments equivalent of [hst.BusConfig].
+func Args(c *hst.BusConfig, bus ProxyPair) (args []string) {
 	argc := 2 + len(c.See) + len(c.Talk) + len(c.Own) + len(c.Call) + len(c.Broadcast)
 	if c.Log {
 		argc++
@@ -119,25 +106,9 @@ func (c *Config) Args(bus ProxyPair) (args []string) {
 	return
 }
 
-func (c *Config) Load(r io.Reader) error { return json.NewDecoder(r).Decode(&c) }
-
-// NewConfigFromFile opens the target config file at path and parses its contents into *Config.
-func NewConfigFromFile(path string) (*Config, error) {
-	if f, err := os.Open(path); err != nil {
-		return nil, err
-	} else {
-		c := new(Config)
-		err1 := c.Load(f)
-		err = f.Close()
-
-		return c, errors.Join(err1, err)
-	}
-}
-
-// NewConfig returns a reference to a Config struct with optional defaults.
-// If id is an empty string own defaults are omitted.
-func NewConfig(id string, defaults, mpris bool) (c *Config) {
-	c = &Config{
+// NewConfig returns the address of a new [hst.BusConfig] with optional defaults.
+func NewConfig(id string, defaults, mpris bool) *hst.BusConfig {
+	c := hst.BusConfig{
 		Call:      make(map[string]string),
 		Broadcast: make(map[string]string),
 
@@ -158,5 +129,5 @@ func NewConfig(id string, defaults, mpris bool) (c *Config) {
 		}
 	}
 
-	return
+	return &c
 }

system/dbus/config_test.go

@@ -1,26 +1,24 @@
 package dbus_test
 
 import (
-	"errors"
-	"os"
-	"path"
 	"reflect"
 	"slices"
 	"strings"
 	"testing"
 
+	"hakurei.app/hst"
 	"hakurei.app/system/dbus"
 )
 
 func TestConfig_Args(t *testing.T) {
-	for _, tc := range makeTestCases() {
+	for _, tc := range testCasesExt {
 		if tc.wantErr {
 			// args does not check for nulls
 			continue
 		}
 
 		t.Run("build arguments for "+tc.id, func(t *testing.T) {
-			if got := tc.c.Args(tc.bus); !slices.Equal(got, tc.want) {
+			if got := dbus.Args(tc.c, tc.bus); !slices.Equal(got, tc.want) {
 				t.Errorf("Args(%q) = %v, want %v",
 					tc.bus,
 					got, tc.want)
@@ -29,74 +27,36 @@ func TestConfig_Args(t *testing.T) {
 	}
 }
 
-func TestNewConfigFromFile(t *testing.T) {
-	for _, tc := range makeTestCases() {
-		name := new(strings.Builder)
-		name.WriteString("parse configuration file for application ")
-		name.WriteString(tc.id)
-		if tc.wantErr {
-			name.WriteString(" with unexpected results")
-		}
-
-		samplePath := path.Join("testdata", tc.id+".json")
-
-		t.Run(name.String(), func(t *testing.T) {
-			got, err := dbus.NewConfigFromFile(samplePath)
-			if errors.Is(err, os.ErrNotExist) != tc.wantErrF {
-				t.Errorf("NewConfigFromFile(%q) error = %v, wantErrF %v",
-					samplePath,
-					err, tc.wantErrF)
-				return
-			}
-
-			if tc.wantErrF {
-				return
-			}
-
-			if !tc.wantErr && !reflect.DeepEqual(got, tc.c) {
-				t.Errorf("NewConfigFromFile(%q) got = %v, want %v",
-					samplePath,
-					got, tc.c)
-			}
-			if tc.wantErr && reflect.DeepEqual(got, tc.c) {
-				t.Errorf("NewConfigFromFile(%q) got = %v, wantErr %v",
-					samplePath,
-					got, tc.wantErr)
-			}
-		})
-	}
-}
-
 func TestNewConfig(t *testing.T) {
 	ids := [...]string{"org.chromium.Chromium", "dev.vencord.Vesktop"}
 
 	type newTestCase struct {
 		id   string
 		args [2]bool
-		want *dbus.Config
+		want *hst.BusConfig
 	}
 
 	// populate tests from IDs in generic tests
 	tcs := make([]newTestCase, 0, (len(ids)+1)*4)
 	// tests for defaults without id
 	tcs = append(tcs,
-		newTestCase{"", [2]bool{false, false}, &dbus.Config{
+		newTestCase{"", [2]bool{false, false}, &hst.BusConfig{
 			Call:      make(map[string]string),
 			Broadcast: make(map[string]string),
 			Filter:    true,
 		}},
-		newTestCase{"", [2]bool{false, true}, &dbus.Config{
+		newTestCase{"", [2]bool{false, true}, &hst.BusConfig{
 			Call:      make(map[string]string),
 			Broadcast: make(map[string]string),
 			Filter:    true,
 		}},
-		newTestCase{"", [2]bool{true, false}, &dbus.Config{
+		newTestCase{"", [2]bool{true, false}, &hst.BusConfig{
 			Talk:      []string{"org.freedesktop.DBus", "org.freedesktop.Notifications"},
 			Call:      map[string]string{"org.freedesktop.portal.*": "*"},
 			Broadcast: map[string]string{"org.freedesktop.portal.*": "@/org/freedesktop/portal/*"},
 			Filter:    true,
 		}},
-		newTestCase{"", [2]bool{true, true}, &dbus.Config{
+		newTestCase{"", [2]bool{true, true}, &hst.BusConfig{
 			Talk:      []string{"org.freedesktop.DBus", "org.freedesktop.Notifications"},
 			Call:      map[string]string{"org.freedesktop.portal.*": "*"},
 			Broadcast: map[string]string{"org.freedesktop.portal.*": "@/org/freedesktop/portal/*"},
@@ -105,24 +65,24 @@ func TestNewConfig(t *testing.T) {
 	)
 	for _, id := range ids {
 		tcs = append(tcs,
-			newTestCase{id, [2]bool{false, false}, &dbus.Config{
+			newTestCase{id, [2]bool{false, false}, &hst.BusConfig{
 				Call:      make(map[string]string),
 				Broadcast: make(map[string]string),
 				Filter:    true,
 			}},
-			newTestCase{id, [2]bool{false, true}, &dbus.Config{
+			newTestCase{id, [2]bool{false, true}, &hst.BusConfig{
 				Call:      make(map[string]string),
 				Broadcast: make(map[string]string),
 				Filter:    true,
 			}},
-			newTestCase{id, [2]bool{true, false}, &dbus.Config{
+			newTestCase{id, [2]bool{true, false}, &hst.BusConfig{
 				Talk:      []string{"org.freedesktop.DBus", "org.freedesktop.Notifications"},
 				Own:       []string{id + ".*"},
 				Call:      map[string]string{"org.freedesktop.portal.*": "*"},
 				Broadcast: map[string]string{"org.freedesktop.portal.*": "@/org/freedesktop/portal/*"},
 				Filter:    true,
 			}},
-			newTestCase{id, [2]bool{true, true}, &dbus.Config{
+			newTestCase{id, [2]bool{true, true}, &hst.BusConfig{
 				Talk:      []string{"org.freedesktop.DBus", "org.freedesktop.Notifications"},
 				Own:       []string{id + ".*", "org.mpris.MediaPlayer2." + id + ".*"},
 				Call:      map[string]string{"org.freedesktop.portal.*": "*"},

system/dbus/dbus_test.go

@@ -22,7 +22,7 @@ func TestFinalise(t *testing.T) {
 			err, syscall.EBADE)
 	}
 
-	for id, tc := range testCasePairs() {
+	for id, tc := range testCasePairs {
 		t.Run("create final for "+id, func(t *testing.T) {
 			var wt io.WriterTo
 			if v, err := dbus.Finalise(tc[0].bus, tc[1].bus, tc[0].c, tc[1].c); (errors.Is(err, syscall.EINVAL)) != tc[0].wantErr {
@@ -105,7 +105,7 @@ func testProxyFinaliseStartWaitCloseString(t *testing.T, useSandbox bool) {
 		}
 	})
 
-	for id, tc := range testCasePairs() {
+	for id, tc := range testCasePairs {
 		// this test does not test errors
 		if tc[0].wantErr {
 			continue

system/dbus/proxy.go

@@ -9,6 +9,7 @@ import (
 
 	"hakurei.app/container"
 	"hakurei.app/helper"
+	"hakurei.app/hst"
 )
 
 // ProxyName is the file name or path to the proxy program.
@@ -66,23 +67,23 @@ type Final struct {
 }
 
 // Finalise creates a checked argument writer for [Proxy].
-func Finalise(sessionBus, systemBus ProxyPair, session, system *Config) (final *Final, err error) {
+func Finalise(sessionBus, systemBus ProxyPair, session, system *hst.BusConfig) (final *Final, err error) {
 	if session == nil && system == nil {
 		return nil, syscall.EBADE
 	}
 
 	var args []string
 	if session != nil {
-		if err = session.checkInterfaces("session"); err != nil {
+		if err = checkInterfaces(session, "session"); err != nil {
 			return
 		}
-		args = append(args, session.Args(sessionBus)...)
+		args = append(args, Args(session, sessionBus)...)
 	}
 	if system != nil {
-		if err = system.checkInterfaces("system"); err != nil {
+		if err = checkInterfaces(system, "system"); err != nil {
 			return
 		}
-		args = append(args, system.Args(systemBus)...)
+		args = append(args, Args(system, systemBus)...)
 	}
 
 	final = &Final{Session: sessionBus, System: systemBus}

system/dbus/samples_test.go

@@ -1,9 +1,7 @@
 package dbus_test
 
 import (
-	"sync"
-
-	"hakurei.app/system/dbus"
+	"hakurei.app/hst"
 )
 
 const (
@@ -14,7 +12,7 @@ const (
 
 var samples = []dbusTestCase{
 	{
-		"org.chromium.Chromium", &dbus.Config{
+		"org.chromium.Chromium", &hst.BusConfig{
 			See: nil,
 			Talk: []string{"org.freedesktop.Notifications", "org.freedesktop.FileManager1", "org.freedesktop.ScreenSaver",
 				"org.freedesktop.secrets", "org.kde.kwalletd5", "org.kde.kwalletd6", "org.gnome.SessionManager"},
@@ -45,7 +43,7 @@ var samples = []dbusTestCase{
 		},
 	},
 	{
-		"org.chromium.Chromium+", &dbus.Config{
+		"org.chromium.Chromium+", &hst.BusConfig{
 			See:       nil,
 			Talk:      []string{"org.bluez", "org.freedesktop.Avahi", "org.freedesktop.UPower"},
 			Own:       nil,
@@ -66,7 +64,7 @@ var samples = []dbusTestCase{
 	},
 
 	{
-		"dev.vencord.Vesktop", &dbus.Config{
+		"dev.vencord.Vesktop", &hst.BusConfig{
 			See:       nil,
 			Talk:      []string{"org.freedesktop.Notifications", "org.kde.StatusNotifierWatcher"},
 			Own:       []string{"dev.vencord.Vesktop.*", "org.mpris.MediaPlayer2.dev.vencord.Vesktop.*"},
@@ -89,7 +87,7 @@ var samples = []dbusTestCase{
 	},
 
 	{
-		"uk.gensokyo.CrashTestDummy", &dbus.Config{
+		"uk.gensokyo.CrashTestDummy", &hst.BusConfig{
 			See:       []string{"uk.gensokyo.CrashTestDummy1"},
 			Talk:      []string{"org.freedesktop.Notifications"},
 			Own:       []string{"uk.gensokyo.CrashTestDummy.*", "org.mpris.MediaPlayer2.uk.gensokyo.CrashTestDummy.*"},
@@ -112,7 +110,7 @@ var samples = []dbusTestCase{
 			"--log"},
 	},
 	{
-		"uk.gensokyo.CrashTestDummy1", &dbus.Config{
+		"uk.gensokyo.CrashTestDummy1", &hst.BusConfig{
 			See:       []string{"uk.gensokyo.CrashTestDummy"},
 			Talk:      []string{"org.freedesktop.Notifications"},
 			Own:       []string{"uk.gensokyo.CrashTestDummy1.*", "org.mpris.MediaPlayer2.uk.gensokyo.CrashTestDummy1.*"},
@@ -138,7 +136,7 @@ var samples = []dbusTestCase{
 
 type dbusTestCase struct {
 	id       string
-	c        *dbus.Config
+	c        *hst.BusConfig
 	wantErr  bool
 	wantErrF bool
 	bus      [2]string
@@ -146,83 +144,71 @@ type dbusTestCase struct {
 }
 
 var (
-	testCasesV     []dbusTestCase
-	testCasePairsV map[string][2]dbusTestCase
+	testCasesExt = func() []dbusTestCase {
+		testCases := make([]dbusTestCase, len(samples)*2)
+		for i := range samples {
+			testCases[i] = samples[i]
 
-	testCaseOnce sync.Once
-)
+			fi := &testCases[len(samples)+i]
+			*fi = samples[i]
 
-func makeTestCases() []dbusTestCase {
-	testCaseOnce.Do(testCaseGenerate)
-	return testCasesV
-}
+			// create null-injected test cases
+			fi.wantErr = true
+			injectNulls := func(t *[]string) {
+				f := make([]string, len(*t))
+				for i := range f {
+					f[i] = "\x00" + (*t)[i] + "\x00"
+				}
+				*t = f
+			}
 
-func testCasePairs() map[string][2]dbusTestCase {
-	testCaseOnce.Do(testCaseGenerate)
-	return testCasePairsV
-}
-
-func injectNulls(t *[]string) {
-	f := make([]string, len(*t))
-	for i := range f {
-		f[i] = "\x00" + (*t)[i] + "\x00"
-	}
-	*t = f
-}
-
-func testCaseGenerate() {
-	// create null-injected test cases
-	testCasesV = make([]dbusTestCase, len(samples)*2)
-	for i := range samples {
-		testCasesV[i] = samples[i]
-		testCasesV[len(samples)+i] = samples[i]
-		testCasesV[len(samples)+i].c = new(dbus.Config)
-		*testCasesV[len(samples)+i].c = *samples[i].c
-
-		// inject nulls
-		fi := &testCasesV[len(samples)+i]
-		fi.wantErr = true
-
-		injectNulls(&fi.c.See)
-		injectNulls(&fi.c.Talk)
-		injectNulls(&fi.c.Own)
-	}
-
-	// enumerate test case pairs
-	var pc int
-	for _, tc := range samples {
-		if tc.id != "" {
-			pc++
-		}
-	}
-	testCasePairsV = make(map[string][2]dbusTestCase, pc)
-	for i, tc := range testCasesV {
-		if tc.id == "" {
-			continue
+			fi.c = new(hst.BusConfig)
+			*fi.c = *samples[i].c
+			injectNulls(&fi.c.See)
+			injectNulls(&fi.c.Talk)
+			injectNulls(&fi.c.Own)
 		}
+		return testCases
+	}()
 
-		// skip already enumerated system bus test
-		if tc.id[len(tc.id)-1] == '+' {
-			continue
-		}
-
-		ftp := [2]dbusTestCase{tc}
-
-		// system proxy tests always place directly after its user counterpart with id ending in +
-		if i+1 < len(testCasesV) && testCasesV[i+1].id[len(testCasesV[i+1].id)-1] == '+' {
-			// attach system bus config
-			ftp[1] = testCasesV[i+1]
-
-			// check for misplaced/mismatching tests
-			if ftp[0].wantErr != ftp[1].wantErr || ftp[0].id+"+" != ftp[1].id {
-				panic("mismatching session/system pairing")
+	testCasePairs = func() map[string][2]dbusTestCase {
+		// enumerate test case pairs
+		var pc int
+		for _, tc := range samples {
+			if tc.id != "" {
+				pc++
 			}
 		}
+		pairs := make(map[string][2]dbusTestCase, pc)
+		for i, tc := range testCasesExt {
+			if tc.id == "" {
+				continue
+			}
 
-		k := tc.id
-		if tc.wantErr {
-			k = "malformed_" + k
+			// skip already enumerated system bus test
+			if tc.id[len(tc.id)-1] == '+' {
+				continue
+			}
+
+			ftp := [2]dbusTestCase{tc}
+
+			// system proxy tests always place directly after its user counterpart with id ending in +
+			if i+1 < len(testCasesExt) && testCasesExt[i+1].id[len(testCasesExt[i+1].id)-1] == '+' {
+				// attach system bus config
+				ftp[1] = testCasesExt[i+1]
+
+				// check for misplaced/mismatching tests
+				if ftp[0].wantErr != ftp[1].wantErr || ftp[0].id+"+" != ftp[1].id {
+					panic("mismatching session/system pairing")
+				}
+			}
+
+			k := tc.id
+			if tc.wantErr {
+				k = "malformed_" + k
+			}
+			pairs[k] = ftp
 		}
-		testCasePairsV[k] = ftp
-	}
-}
+		return pairs
+	}()
+)