hst/dbus: validate interface strings

This is relocated to hst to validate early.

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

system/dbus/config.go

@@ -1,74 +1,12 @@
 package dbus
 
 import (
-	"strings"
-
 	"hakurei.app/hst"
 )
 
 // ProxyPair is an upstream dbus address and a downstream socket path.
 type ProxyPair [2]string
 
-// 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.Own {
-			if !yield(iface) {
-				return
-			}
-		}
-
-		for iface := range c.Call {
-			if !yield(iface) {
-				return
-			}
-		}
-		for iface := range c.Broadcast {
-			if !yield(iface) {
-				return
-			}
-		}
-	}
-}
-
-// 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, '.');
-				if (dot != NULL)
-				  {
-				    *dot = 0;
-				    if (strcmp (dot + 1, "*") != 0)
-				      filter->member = g_strdup (dot + 1);
-				  }
-
-			trim ".*" since they are removed before searching for '.':
-				if (g_str_has_suffix (name, ".*"))
-				  {
-				    name[strlen (name) - 2] = 0;
-				    wildcard = TRUE;
-				  }
-		*/
-		if strings.IndexByte(strings.TrimSuffix(iface, ".*"), '.') == -1 {
-			return &BadInterfaceError{iface, segment}
-		}
-	}
-	return nil
-}
-
 // 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)

system/dbus/config_test.go

@@ -10,7 +10,7 @@ import (
 	"hakurei.app/system/dbus"
 )
 
-func TestConfig_Args(t *testing.T) {
+func TestConfigArgs(t *testing.T) {
 	for _, tc := range testCasesExt {
 		if tc.wantErr {
 			// args does not check for nulls
@@ -19,9 +19,7 @@ func TestConfig_Args(t *testing.T) {
 
 		t.Run("build arguments for "+tc.id, func(t *testing.T) {
 			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)
+				t.Errorf("Args: %v, want %v", got, tc.want)
 			}
 		})
 	}

system/dbus/proxy.go

@@ -2,7 +2,6 @@ package dbus
 
 import (
 	"context"
-	"fmt"
 	"io"
 	"sync"
 	"syscall"
@@ -16,15 +15,6 @@ import (
 // Overriding ProxyName will only affect Proxy instance created after the change.
 var ProxyName = "xdg-dbus-proxy"
 
-type BadInterfaceError struct {
-	Interface string
-	Segment   string
-}
-
-func (e *BadInterfaceError) Error() string {
-	return fmt.Sprintf("bad interface string %q in %s bus configuration", e.Interface, e.Segment)
-}
-
 // Proxy holds the state of a xdg-dbus-proxy process, and should never be copied.
 type Proxy struct {
 	helper helper.Helper
@@ -74,13 +64,13 @@ func Finalise(sessionBus, systemBus ProxyPair, session, system *hst.BusConfig) (
 
 	var args []string
 	if session != nil {
-		if err = checkInterfaces(session, "session"); err != nil {
+		if err = session.CheckInterfaces("session"); err != nil {
 			return
 		}
 		args = append(args, Args(session, sessionBus)...)
 	}
 	if system != nil {
-		if err = checkInterfaces(system, "system"); err != nil {
+		if err = system.CheckInterfaces("system"); err != nil {
 			return
 		}
 		args = append(args, Args(system, systemBus)...)