system/dbus: remove builder state leak

This enables external testing of system.I state.

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

5 files changed, 62 insertions, 54 deletions

diff --git a/system/dbus.go b/system/dbus.go
index 1cc24a22..424f9dfa 100644
--- a/system/dbus.go
+++ b/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 = errors.New("dbus config not supplied")
-)
+// ErrDBusConfig is returned when a required [hst.BusConfig] argument is nil.
+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 {
-	if err := sys.ProxyDBus(session, system, sessionPath, systemPath); err != nil {
+func (sys *I) MustProxyDBus(
+	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) {
diff --git a/system/dbus/dbus.go b/system/dbus/dbus.go
index 08db8f1b..9ea89f51 100644
--- a/system/dbus/dbus.go
+++ b/system/dbus/dbus.go
@@ -8,27 +8,31 @@ 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.
+		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.
 
-	The address of the login session message bus is given in the DBUS_SESSION_BUS_ADDRESS environment variable.
-	If DBUS_SESSION_BUS_ADDRESS is not set, or if it's set to the string "autolaunch:",
-	the system should use platform-specific methods of locating a running D-Bus session server,
-	or starting one if a running instance cannot be found.
-	Note that this mechanism is not recommended for attempting to determine if a daemon is running.
-	It is inherently racy to attempt to make this determination, since the bus daemon may be started just before or just after the determination is made.
-	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.
+		The address of the login session message bus is given in the DBUS_SESSION_BUS_ADDRESS environment variable.
+		If DBUS_SESSION_BUS_ADDRESS is not set, or if it's set to the string "autolaunch:",
+		the system should use platform-specific methods of locating a running D-Bus session server,
+		or starting one if a running instance cannot be found.
+		Note that this mechanism is not recommended for attempting to determine if a daemon is running.
+		It is inherently racy to attempt to make this determination, since the bus daemon may be started just before or just after the determination is made.
+		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.*/
+		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.
+	*/
 	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.*/
+		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.
+	*/
 	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]
 }
diff --git a/system/dbus_test.go b/system/dbus_test.go
index 2a1f12db..a346711e 100644
--- a/system/dbus_test.go
+++ b/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,
-				},
-				m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/bus"),
-				m("/tmp/hakurei.0/99dd71ee2146369514e0d10783368f8f/system_bus_socket")); !reflect.DeepEqual(err, wantErr) {
+				}, 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",
+				}); !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"},
diff --git a/system/dispatcher.go b/system/dispatcher.go
index 3f17dc1a..cdc95072 100644
--- a/system/dispatcher.go
+++ b/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)
 }
diff --git a/system/dispatcher_test.go b/system/dispatcher_test.go
index 5edc2751..fd6e5d09 100644
--- a/system/dispatcher_test.go
+++ b/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")