system/link: use syscall dispatcher

This enables hardlink op methods to be instrumented.

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

system/acl_test.go

@@ -54,7 +54,7 @@ func TestACLUpdateOp(t *testing.T) {
 			}, nil},
 	})
 
-	checkOpsBuilder(t, "UpdatePerm", []opsBuilderTestCase{
+	checkOpsBuilder(t, "UpdatePermType", []opsBuilderTestCase{
 		{"simple",
 			0xdeadbeef,
 			func(_ *testing.T, sys *I) {
@@ -65,8 +65,7 @@ func TestACLUpdateOp(t *testing.T) {
 				&aclUpdateOp{Process, "/run/user/1971/hakurei", []acl.Perm{acl.Execute}},
 				&aclUpdateOp{Process, "/tmp/hakurei.0/tmpdir/150", []acl.Perm{acl.Read, acl.Write, acl.Execute}},
 			}, stub.Expect{}},
-	})
+
-	checkOpsBuilder(t, "UpdatePermType", []opsBuilderTestCase{
 		{"tmpdirp", 0xdeadbeef, func(_ *testing.T, sys *I) {
 			sys.UpdatePermType(User, "/tmp/hakurei.0/tmpdir", acl.Execute)
 		}, []Op{

system/dispatcher.go

@@ -1,6 +1,8 @@
 package system
 
 import (
+	"os"
+
 	"hakurei.app/system/acl"
 	"hakurei.app/system/dbus"
 )
@@ -13,6 +15,11 @@ type syscallDispatcher interface {
 	// just synchronising access is not enough, as this is for test instrumentation.
 	new(f func(k syscallDispatcher))
 
+	// link provides os.Link.
+	link(oldname, newname string) error
+	// remove provides os.Remove.
+	remove(name string) error
+
 	// aclUpdate provides [acl.Update].
 	aclUpdate(name string, uid int, perms ...acl.Perm) error
 
@@ -37,6 +44,9 @@ type direct struct{}
 
 func (k direct) new(f func(k syscallDispatcher)) { go f(k) }
 
+func (k direct) link(oldname, newname string) error { return os.Link(oldname, newname) }
+func (k direct) remove(name string) error           { return os.Remove(name) }
+
 func (k direct) aclUpdate(name string, uid int, perms ...acl.Perm) error {
 	return acl.Update(name, uid, perms...)
 }

system/dispatcher_test.go

@@ -192,6 +192,19 @@ type kstub struct{ *stub.Stub[syscallDispatcher] }
 
 func (k *kstub) new(f func(k syscallDispatcher)) { k.Helper(); k.New(f) }
 
+func (k *kstub) link(oldname, newname string) error {
+	k.Helper()
+	return k.Expects("link").Error(
+		stub.CheckArg(k.Stub, "oldname", oldname, 0),
+		stub.CheckArg(k.Stub, "newname", newname, 1))
+}
+
+func (k *kstub) remove(name string) error {
+	k.Helper()
+	return k.Expects("remove").Error(
+		stub.CheckArg(k.Stub, "name", name, 0))
+}
+
 func (k *kstub) aclUpdate(name string, uid int, perms ...acl.Perm) error {
 	k.Helper()
 	return k.Expects("aclUpdate").Error(

system/link.go

@@ -2,7 +2,6 @@ package system
 
 import (
 	"fmt"
-	"os"
 )
 
 // Link calls LinkFileType with the [Process] criteria.
@@ -22,17 +21,17 @@ type hardlinkOp struct {
 
 func (l *hardlinkOp) Type() Enablement { return l.et }
 
-func (l *hardlinkOp) apply(*I) error {
+func (l *hardlinkOp) apply(sys *I) error {
-	msg.Verbose("linking", l)
+	sys.verbose("linking", l)
-	return newOpError("hardlink", os.Link(l.src, l.dst), false)
+	return newOpError("hardlink", sys.link(l.src, l.dst), false)
 }
 
-func (l *hardlinkOp) revert(_ *I, ec *Criteria) error {
+func (l *hardlinkOp) revert(sys *I, ec *Criteria) error {
 	if ec.hasType(l.Type()) {
-		msg.Verbosef("removing hard link %q", l.dst)
+		sys.verbosef("removing hard link %q", l.dst)
-		return newOpError("hardlink", os.Remove(l.dst), true)
+		return newOpError("hardlink", sys.remove(l.dst), true)
 	} else {
-		msg.Verbosef("skipping hard link %q", l.dst)
+		sys.verbosef("skipping hard link %q", l.dst)
 		return nil
 	}
 }

system/link_test.go

@@ -0,0 +1,84 @@
+package system
+
+import (
+	"testing"
+
+	"hakurei.app/container/stub"
+)
+
+func TestHardlinkOp(t *testing.T) {
+	checkOpBehaviour(t, []opBehaviourTestCase{
+		{"link", 0xdeadbeef, 0xff, &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}, []stub.Call{
+			call("verbose", stub.ExpectArgs{[]any{"linking", &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}}}, nil, nil),
+			call("link", stub.ExpectArgs{"/run/user/1000/pulse/native", "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}, nil, stub.UniqueError(1)),
+		}, &OpError{Op: "hardlink", Err: stub.UniqueError(1)}, nil, nil},
+
+		{"remove", 0xdeadbeef, 0xff, &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}, []stub.Call{
+			call("verbose", stub.ExpectArgs{[]any{"linking", &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}}}, nil, nil),
+			call("link", stub.ExpectArgs{"/run/user/1000/pulse/native", "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}, nil, nil),
+		}, nil, []stub.Call{
+			call("verbosef", stub.ExpectArgs{"removing hard link %q", []any{"/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}}, nil, nil),
+			call("remove", stub.ExpectArgs{"/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}, nil, stub.UniqueError(0)),
+		}, &OpError{Op: "hardlink", Err: stub.UniqueError(0), Revert: true}},
+
+		{"success skip", 0xdeadbeef, EWayland | EX11, &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}, []stub.Call{
+			call("verbose", stub.ExpectArgs{[]any{"linking", &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}}}, nil, nil),
+			call("link", stub.ExpectArgs{"/run/user/1000/pulse/native", "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}, nil, nil),
+		}, nil, []stub.Call{
+			call("verbosef", stub.ExpectArgs{"skipping hard link %q", []any{"/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}}, nil, nil),
+		}, nil},
+
+		{"success", 0xdeadbeef, 0xff, &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}, []stub.Call{
+			call("verbose", stub.ExpectArgs{[]any{"linking", &hardlinkOp{EPulse, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"}}}, nil, nil),
+			call("link", stub.ExpectArgs{"/run/user/1000/pulse/native", "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}, nil, nil),
+		}, nil, []stub.Call{
+			call("verbosef", stub.ExpectArgs{"removing hard link %q", []any{"/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}}, nil, nil),
+			call("remove", stub.ExpectArgs{"/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse"}, nil, nil),
+		}, nil},
+	})
+
+	checkOpsBuilder(t, "LinkFileType", []opsBuilderTestCase{
+		{"type", 0xcafebabe, func(_ *testing.T, sys *I) {
+			sys.LinkFileType(User, "/run/user/1000/pulse/native", "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse")
+		}, []Op{
+			&hardlinkOp{User, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+		}, stub.Expect{}},
+
+		{"link", 0xcafebabe, func(_ *testing.T, sys *I) {
+			sys.Link("/run/user/1000/pulse/native", "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse")
+		}, []Op{
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+		}, stub.Expect{}},
+	})
+
+	checkOpIs(t, []opIsTestCase{
+		{"nil", (*hardlinkOp)(nil), (*hardlinkOp)(nil), false},
+		{"zero", new(hardlinkOp), new(hardlinkOp), true},
+
+		{"src differs",
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse"},
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+			false},
+
+		{"dst differs",
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6", "/run/user/1000/pulse/native"},
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+			false},
+
+		{"et differs",
+			&hardlinkOp{User, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+			false},
+
+		{"equals",
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+			&hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+			true},
+	})
+
+	checkOpMeta(t, []opMetaTestCase{
+		{"link", &hardlinkOp{Process, "/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse", "/run/user/1000/pulse/native"},
+			Process, "/run/user/1000/pulse/native",
+			`"/run/user/1000/hakurei/9663730666a44cfc2a81610379e02ed6/pulse" from "/run/user/1000/pulse/native"`},
+	})
+}

system/tmpfiles_test.go

@@ -24,43 +24,6 @@ func TestCopyFile(t *testing.T) {
 	}
 }
 
-func TestLink(t *testing.T) {
-	testCases := []struct {
-		dst, src string
-	}{
-		{"/tmp/hakurei.1971/f587afe9fce3c8e1ad5b64deb6c41ad5/pulse-cookie", "/home/ophestra/xdg/config/pulse/cookie"},
-		{"/tmp/hakurei.1971/62154f708b5184ab01f9dcc2bbe7a33b/pulse-cookie", "/home/ophestra/xdg/config/pulse/cookie"},
-	}
-	for _, tc := range testCases {
-		t.Run("link file "+tc.dst+" from "+tc.src, func(t *testing.T) {
-			sys := New(t.Context(), 150)
-			sys.Link(tc.src, tc.dst)
-			(&tcOp{Process, tc.src}).test(t, sys.ops, []Op{
-				&hardlinkOp{Process, tc.dst, tc.src},
-			}, "Link")
-		})
-	}
-}
-
-func TestLinkFileType(t *testing.T) {
-	testCases := []struct {
-		tcOp
-		dst string
-	}{
-		{tcOp{User, "/tmp/hakurei.1971/f587afe9fce3c8e1ad5b64deb6c41ad5/pulse-cookie"}, "/home/ophestra/xdg/config/pulse/cookie"},
-		{tcOp{Process, "/tmp/hakurei.1971/62154f708b5184ab01f9dcc2bbe7a33b/pulse-cookie"}, "/home/ophestra/xdg/config/pulse/cookie"},
-	}
-	for _, tc := range testCases {
-		t.Run("link file "+tc.dst+" from "+tc.path+" with type "+TypeString(tc.et), func(t *testing.T) {
-			sys := New(t.Context(), 150)
-			sys.LinkFileType(tc.et, tc.path, tc.dst)
-			tc.test(t, sys.ops, []Op{
-				&hardlinkOp{tc.et, tc.dst, tc.path},
-			}, "LinkFileType")
-		})
-	}
-}
-
 func TestTmpfile_String(t *testing.T) {
 	testCases := []struct {
 		src  string