system/dbus: remove builder state leak

This enables external testing of system.I state.

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

internal/app/app_test.go

@@ -25,6 +25,7 @@ import (
 	"hakurei.app/message"
 	"hakurei.app/system"
 	"hakurei.app/system/acl"
+	"hakurei.app/system/dbus"
 )
 
 func TestApp(t *testing.T) {
@@ -213,7 +214,7 @@ func TestApp(t *testing.T) {
 				Ensure(m("/run/user/1971"), 0700).UpdatePermType(system.User, m("/run/user/1971"), acl.Execute). // this is ordered as is because the previous Ensure only calls mkdir if XDG_RUNTIME_DIR is unset
 				Ephemeral(system.Process, m("/run/user/1971/hakurei/ebf083d1b175911782d413369b64ce7c"), 0700).UpdatePermType(system.Process, m("/run/user/1971/hakurei/ebf083d1b175911782d413369b64ce7c"), acl.Execute).
 				Link(m("/run/user/1971/pulse/native"), m("/run/user/1971/hakurei/ebf083d1b175911782d413369b64ce7c/pulse")).
-				MustProxyDBus(m("/tmp/hakurei.0/ebf083d1b175911782d413369b64ce7c/bus"), &hst.BusConfig{
+				MustProxyDBus(&hst.BusConfig{
 					Talk: []string{
 						"org.freedesktop.Notifications",
 						"org.freedesktop.FileManager1",
@@ -235,13 +236,19 @@ func TestApp(t *testing.T) {
 						"org.freedesktop.portal.*": "@/org/freedesktop/portal/*",
 					},
 					Filter: true,
-				}, m("/tmp/hakurei.0/ebf083d1b175911782d413369b64ce7c/system_bus_socket"), &hst.BusConfig{
+				}, &hst.BusConfig{
 					Talk: []string{
 						"org.bluez",
 						"org.freedesktop.Avahi",
 						"org.freedesktop.UPower",
 					},
 					Filter: true,
+				}, dbus.ProxyPair{
+					"unix:path=/run/user/1971/bus",
+					"/tmp/hakurei.0/ebf083d1b175911782d413369b64ce7c/bus",
+				}, dbus.ProxyPair{
+					"unix:path=/var/run/dbus/system_bus_socket",
+					"/tmp/hakurei.0/ebf083d1b175911782d413369b64ce7c/system_bus_socket",
 				}).
 				UpdatePerm(m("/tmp/hakurei.0/ebf083d1b175911782d413369b64ce7c/bus"), acl.Read, acl.Write).
 				UpdatePerm(m("/tmp/hakurei.0/ebf083d1b175911782d413369b64ce7c/system_bus_socket"), acl.Read, acl.Write),
@@ -364,7 +371,7 @@ func TestApp(t *testing.T) {
 				Ephemeral(system.Process, m("/run/user/1971/hakurei/8e2c76b066dabe574cf073bdb46eb5c1"), 0700).UpdatePermType(system.Process, m("/run/user/1971/hakurei/8e2c76b066dabe574cf073bdb46eb5c1"), acl.Execute).
 				Link(m("/run/user/1971/pulse/native"), m("/run/user/1971/hakurei/8e2c76b066dabe574cf073bdb46eb5c1/pulse")).
 				Ephemeral(system.Process, m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1"), 0711).
-				MustProxyDBus(m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/bus"), &hst.BusConfig{
+				MustProxyDBus(&hst.BusConfig{
 					Talk: []string{
 						"org.freedesktop.FileManager1", "org.freedesktop.Notifications",
 						"org.freedesktop.ScreenSaver", "org.freedesktop.secrets",
@@ -377,13 +384,19 @@ func TestApp(t *testing.T) {
 					},
 					Call: map[string]string{}, Broadcast: map[string]string{},
 					Filter: true,
-				}, m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/system_bus_socket"), &hst.BusConfig{
+				}, &hst.BusConfig{
 					Talk: []string{
 						"org.bluez",
 						"org.freedesktop.Avahi",
 						"org.freedesktop.UPower",
 					},
 					Filter: true,
+				}, dbus.ProxyPair{
+					"unix:path=/run/user/1971/bus",
+					"/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/bus",
+				}, dbus.ProxyPair{
+					"unix:path=/var/run/dbus/system_bus_socket",
+					"/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/system_bus_socket",
 				}).
 				UpdatePerm(m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/bus"), acl.Read, acl.Write).
 				UpdatePerm(m("/tmp/hakurei.0/8e2c76b066dabe574cf073bdb46eb5c1/system_bus_socket"), acl.Read, acl.Write),
@@ -739,6 +752,10 @@ func (k *stubNixOS) overflowGid(message.Msg) int { return 65534 }
 
 func (k *stubNixOS) mustHsuPath() *check.Absolute { return m("/proc/nonexistent/hsu") }
 
+func (k *stubNixOS) dbusAddress() (string, string) {
+	return "unix:path=/run/user/1971/bus", "unix:path=/var/run/dbus/system_bus_socket"
+}
+
 func (k *stubNixOS) fatalf(format string, v ...any) { panic(fmt.Sprintf(format, v...)) }
 
 func (k *stubNixOS) isVerbose() bool                  { return true }

internal/app/dispatcher.go

@@ -13,6 +13,7 @@ import (
 	"hakurei.app/container/check"
 	"hakurei.app/internal"
 	"hakurei.app/message"
+	"hakurei.app/system/dbus"
 )
 
 // osFile represents [os.File].
@@ -63,6 +64,9 @@ type syscallDispatcher interface {
 	// mustHsuPath provides [internal.MustHsuPath].
 	mustHsuPath() *check.Absolute
 
+	// dbusAddress provides [dbus.Address].
+	dbusAddress() (session, system string)
+
 	// fatalf provides [log.Fatalf].
 	fatalf(format string, v ...any)
 }
@@ -99,4 +103,6 @@ func (direct) overflowGid(msg message.Msg) int { return container.OverflowGid(ms
 
 func (direct) mustHsuPath() *check.Absolute { return internal.MustHsuPath() }
 
+func (k direct) dbusAddress() (session, system string) { return dbus.Address() }
+
 func (direct) fatalf(format string, v ...any) { log.Fatalf(format, v...) }

internal/app/dispatcher_test.go

@@ -97,7 +97,7 @@ func checkOpBehaviour(t *testing.T, testCases []opBehaviourTestCase) {
 				if err := s.populateLocal(k, k); err != nil {
 					t.Fatalf("populateLocal: error = %v", err)
 				}
-				stateSys := s.newSys(config, newI())
+				stateSys := s.newSys(config, system.New(panicMsgContext{}, k, checkExpectUid))
 				if tc.pStateSys != nil {
 					tc.pStateSys(stateSys)
 				}
@@ -218,6 +218,12 @@ func (k *kstub) mustHsuPath() *check.Absolute {
 	return k.Expects("mustHsuPath").Ret.(*check.Absolute)
 }
 
+func (k *kstub) dbusAddress() (session, system string) {
+	k.Helper()
+	ret := k.Expects("dbusAddress").Ret.([2]string)
+	return ret[0], ret[1]
+}
+
 func (k *kstub) GetLogger() *log.Logger { panic("unreachable") }
 
 func (k *kstub) IsVerbose() bool { k.Helper(); return k.Expects("isVerbose").Ret.(bool) }
@@ -320,4 +326,5 @@ func (panicDispatcher) cmdOutput(*exec.Cmd) ([]byte, error)   { panic("unreachab
 func (panicDispatcher) overflowUid(message.Msg) int           { panic("unreachable") }
 func (panicDispatcher) overflowGid(message.Msg) int           { panic("unreachable") }
 func (panicDispatcher) mustHsuPath() *check.Absolute          { panic("unreachable") }
+func (panicDispatcher) dbusAddress() (string, string)         { panic("unreachable") }
 func (panicDispatcher) fatalf(string, ...any)                 { panic("unreachable") }

internal/app/spdbus.go

@@ -13,8 +13,7 @@ func init() { gob.Register(new(spDBusOp)) }
 
 // spDBusOp maintains an xdg-dbus-proxy instance for the container.
 type spDBusOp struct {
-	// Whether to bind the system bus socket.
+	// Whether to bind the system bus socket. Populated during toSystem.
-	// Populated during toSystem.
 	ProxySystem bool
 }
 
@@ -30,10 +29,10 @@ func (s *spDBusOp) toSystem(state *outcomeStateSys) error {
 	// downstream socket paths
 	sessionPath, systemPath := state.instance().Append("bus"), state.instance().Append("system_bus_socket")
 
-	if err := state.sys.ProxyDBus(
+	var sessionBus, systemBus dbus.ProxyPair
-		state.sessionBus, state.systemBus,
+	sessionBus[0], systemBus[0] = state.k.dbusAddress()
-		sessionPath, systemPath,
+	sessionBus[1], systemBus[1] = sessionPath.String(), systemPath.String()
-	); err != nil {
+	if err := state.sys.ProxyDBus(state.sessionBus, state.systemBus, sessionBus, systemBus); err != nil {
 		return err
 	}
 

system/dbus.go

@@ -12,18 +12,19 @@ import (
 	"syscall"
 
 	"hakurei.app/container"
-	"hakurei.app/container/check"
 	"hakurei.app/hst"
 	"hakurei.app/system/dbus"
 )
 
-var (
+// ErrDBusConfig is returned when a required [hst.BusConfig] argument is nil.
-	ErrDBusConfig = errors.New("dbus config not supplied")
+var ErrDBusConfig = errors.New("dbus config not supplied")
-)
 
 // MustProxyDBus calls ProxyDBus and panics if an error is returned.
-func (sys *I) MustProxyDBus(sessionPath *check.Absolute, session *hst.BusConfig, systemPath *check.Absolute, system *hst.BusConfig) *I {
+func (sys *I) MustProxyDBus(
-	if err := sys.ProxyDBus(session, system, sessionPath, systemPath); err != nil {
+	session, system *hst.BusConfig,
+	sessionBus, systemBus dbus.ProxyPair,
+) *I {
+	if err := sys.ProxyDBus(session, system, sessionBus, systemBus); err != nil {
 		panic(err.Error())
 	} else {
 		return sys
@@ -32,7 +33,10 @@ func (sys *I) MustProxyDBus(sessionPath *check.Absolute, session *hst.BusConfig,
 
 // ProxyDBus finalises configuration ahead of time and starts xdg-dbus-proxy via [dbus] and terminates it on revert.
 // This [Op] is always [Process] scoped.
-func (sys *I) ProxyDBus(session, system *hst.BusConfig, sessionPath, systemPath *check.Absolute) error {
+func (sys *I) ProxyDBus(
+	session, system *hst.BusConfig,
+	sessionBus, systemBus dbus.ProxyPair,
+) error {
 	d := new(dbusProxyOp)
 
 	// session bus is required as otherwise this is effectively a very expensive noop
@@ -44,9 +48,6 @@ func (sys *I) ProxyDBus(session, system *hst.BusConfig, sessionPath, systemPath
 	// system bus is optional
 	d.system = system != nil
 
-	var sessionBus, systemBus dbus.ProxyPair
-	sessionBus[0], systemBus[0] = sys.dbusAddress()
-	sessionBus[1], systemBus[1] = sessionPath.String(), systemPath.String()
 	d.out = &linePrefixWriter{println: log.Println, prefix: "(dbus) ", buf: new(strings.Builder)}
 	if final, err := sys.dbusFinalise(sessionBus, systemBus, session, system); err != nil {
 		if errors.Is(err, syscall.EINVAL) {

system/dbus/dbus.go

@@ -8,7 +8,8 @@ import (
 )
 
 const (
-	/*SessionBusAddress is the name of the environment variable where the address of the login session message bus is given in.
+	/*
+		SessionBusAddress is the name of the environment variable where the address of the login session message bus is given in.
 
 		If that variable is not set, applications may also try to read the address from the X Window System root window property _DBUS_SESSION_BUS_ADDRESS.
 		The root window property must have type STRING. The environment variable should have precedence over the root window property.
@@ -22,13 +23,16 @@ const (
 		Therefore, it is recommended that applications do not try to make this determination for their functionality purposes, and instead they should attempt to start the server.
 
 		This package diverges from the specification, as the caller is unlikely to be an X client, or be in a position to autolaunch a dbus server.
-	So a fallback address with a socket located in the well-known default XDG_RUNTIME_DIR formatting is used.*/
+		So a fallback address with a socket located in the well-known default XDG_RUNTIME_DIR formatting is used.
+	*/
 	SessionBusAddress = "DBUS_SESSION_BUS_ADDRESS"
 
-	/*SystemBusAddress is the name of the environment variable where the address of the system message bus is given in.
+	/*
+		SystemBusAddress is the name of the environment variable where the address of the system message bus is given in.
 
 		If that variable is not set, applications should try to connect to the well-known address unix:path=/var/run/dbus/system_bus_socket.
-	Implementations of the well-known system bus should listen on an address that will result in that connection being successful.*/
+		Implementations of the well-known system bus should listen on an address that will result in that connection being successful.
+	*/
 	SystemBusAddress = "DBUS_SYSTEM_BUS_ADDRESS"
 
 	// FallbackSystemBusAddress is used when [SystemBusAddress] is not set.
@@ -36,28 +40,30 @@ const (
 )
 
 var (
-	addresses   [2]string
+	address     [2]string
 	addressOnce sync.Once
 )
 
+// Address returns the session and system bus addresses copied from environment,
+// or appropriate fallback values if they are not set.
 func Address() (session, system string) {
 	addressOnce.Do(func() {
 		// resolve upstream session bus address
 		if addr, ok := os.LookupEnv(SessionBusAddress); !ok {
 			// fall back to default format
-			addresses[0] = fmt.Sprintf("unix:path=/run/user/%d/bus", os.Getuid())
+			address[0] = fmt.Sprintf("unix:path=/run/user/%d/bus", os.Getuid())
 		} else {
-			addresses[0] = addr
+			address[0] = addr
 		}
 
 		// resolve upstream system bus address
 		if addr, ok := os.LookupEnv(SystemBusAddress); !ok {
 			// fall back to default hardcoded value
-			addresses[1] = FallbackSystemBusAddress
+			address[1] = FallbackSystemBusAddress
 		} else {
-			addresses[1] = addr
+			address[1] = addr
 		}
 	})
 
-	return addresses[0], addresses[1]
+	return address[0], address[1]
 }

system/dbus_test.go

@@ -85,7 +85,7 @@ func TestDBusProxyOp(t *testing.T) {
 				Op: "dbus", Err: ErrDBusConfig,
 				Msg: "attempted to create message bus proxy args without session bus config",
 			}
-			if err := sys.ProxyDBus(nil, new(hst.BusConfig), nil, nil); !reflect.DeepEqual(err, wantErr) {
+			if err := sys.ProxyDBus(nil, new(hst.BusConfig), dbus.ProxyPair{}, dbus.ProxyPair{}); !reflect.DeepEqual(err, wantErr) {
 				t.Errorf("ProxyDBus: error = %v, want %v", err, wantErr)
 			}
 		}, nil, stub.Expect{}},
@@ -99,15 +99,20 @@ func TestDBusProxyOp(t *testing.T) {
 			}()
 
 			sys.MustProxyDBus(
-				m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus"), &hst.BusConfig{
+				&hst.BusConfig{
 					// use impossible value here as an implicit assert that it goes through the stub
 					Talk: []string{"session\x00"}, Filter: true,
-				}, m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket"), &hst.BusConfig{
+				}, &hst.BusConfig{
 					// use impossible value here as an implicit assert that it goes through the stub
 					Talk: []string{"system\x00"}, Filter: true,
+				}, dbus.ProxyPair{
+					"unix:path=/run/user/1000/bus",
+					"/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus",
+				}, dbus.ProxyPair{
+					"unix:path=/run/dbus/system_bus_socket",
+					"/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket",
 				})
 		}, nil, stub.Expect{Calls: []stub.Call{
-			call("dbusAddress", stub.ExpectArgs{}, [2]string{"unix:path=/run/user/1000/bus", "unix:path=/run/dbus/system_bus_socket"}, nil),
 			call("dbusFinalise", stub.ExpectArgs{
 				dbus.ProxyPair{"unix:path=/run/user/1000/bus", "/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus"},
 				dbus.ProxyPair{"unix:path=/run/dbus/system_bus_socket", "/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket"},
@@ -128,13 +133,16 @@ func TestDBusProxyOp(t *testing.T) {
 				}, &hst.BusConfig{
 					// use impossible value here as an implicit assert that it goes through the stub
 					Talk: []string{"system\x00"}, Filter: true,
-				},
+				}, dbus.ProxyPair{
-				m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus"),
+					"unix:path=/run/user/1000/bus",
-				m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket")); !reflect.DeepEqual(err, wantErr) {
+					"/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus",
+				}, dbus.ProxyPair{
+					"unix:path=/run/dbus/system_bus_socket",
+					"/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket",
+				}); !reflect.DeepEqual(err, wantErr) {
 				t.Errorf("ProxyDBus: error = %v", err)
 			}
 		}, nil, stub.Expect{Calls: []stub.Call{
-			call("dbusAddress", stub.ExpectArgs{}, [2]string{"unix:path=/run/user/1000/bus", "unix:path=/run/dbus/system_bus_socket"}, nil),
 			call("dbusFinalise", stub.ExpectArgs{
 				dbus.ProxyPair{"unix:path=/run/user/1000/bus", "/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus"},
 				dbus.ProxyPair{"unix:path=/run/dbus/system_bus_socket", "/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket"},
@@ -145,12 +153,18 @@ func TestDBusProxyOp(t *testing.T) {
 
 		{"full", 0xcafebabe, func(_ *testing.T, sys *I) {
 			sys.MustProxyDBus(
-				m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus"), &hst.BusConfig{
+				&hst.BusConfig{
 					// use impossible value here as an implicit assert that it goes through the stub
 					Talk: []string{"session\x00"}, Filter: true,
-				}, m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket"), &hst.BusConfig{
+				}, &hst.BusConfig{
 					// use impossible value here as an implicit assert that it goes through the stub
 					Talk: []string{"system\x00"}, Filter: true,
+				}, dbus.ProxyPair{
+					"unix:path=/run/user/1000/bus",
+					"/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus",
+				}, dbus.ProxyPair{
+					"unix:path=/run/dbus/system_bus_socket",
+					"/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket",
 				})
 		}, []Op{
 			&dbusProxyOp{
@@ -158,7 +172,6 @@ func TestDBusProxyOp(t *testing.T) {
 				system: true,
 			},
 		}, stub.Expect{Calls: []stub.Call{
-			call("dbusAddress", stub.ExpectArgs{}, [2]string{"unix:path=/run/user/1000/bus", "unix:path=/run/dbus/system_bus_socket"}, nil),
 			call("dbusFinalise", stub.ExpectArgs{
 				dbus.ProxyPair{"unix:path=/run/user/1000/bus", "/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus"},
 				dbus.ProxyPair{"unix:path=/run/dbus/system_bus_socket", "/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket"},

system/dispatcher.go

@@ -48,8 +48,6 @@ type syscallDispatcher interface {
 	// xcbChangeHosts provides [xcb.ChangeHosts].
 	xcbChangeHosts(mode xcb.HostMode, family xcb.Family, address string) error
 
-	// dbusAddress provides [dbus.Address].
-	dbusAddress() (session, system string)
 	// dbusFinalise provides [dbus.Finalise].
 	dbusFinalise(sessionBus, systemBus dbus.ProxyPair, session, system *hst.BusConfig) (final *dbus.Final, err error)
 	// dbusProxyStart provides the Start method of [dbus.Proxy].
@@ -82,10 +80,6 @@ func (k direct) xcbChangeHosts(mode xcb.HostMode, family xcb.Family, address str
 	return xcb.ChangeHosts(mode, family, address)
 }
 
-func (k direct) dbusAddress() (session, system string) {
-	return dbus.Address()
-}
-
 func (k direct) dbusFinalise(sessionBus, systemBus dbus.ProxyPair, session, system *hst.BusConfig) (final *dbus.Final, err error) {
 	return dbus.Finalise(sessionBus, systemBus, session, system)
 }

system/dispatcher_test.go

@@ -276,12 +276,6 @@ func (k *kstub) xcbChangeHosts(mode xcb.HostMode, family xcb.Family, address str
 		stub.CheckArg(k.Stub, "address", address, 2))
 }
 
-func (k *kstub) dbusAddress() (session, system string) {
-	k.Helper()
-	ret := k.Expects("dbusAddress").Ret.([2]string)
-	return ret[0], ret[1]
-}
-
 func (k *kstub) dbusFinalise(sessionBus, systemBus dbus.ProxyPair, session, system *hst.BusConfig) (final *dbus.Final, err error) {
 	k.Helper()
 	expect := k.Expects("dbusFinalise")