app: move wayland mediation to shim package

Values used in the Wayland mediation implementation is stored in various struct fields strewn across multiple app structs and checks are messy and confusing. This commit unifies them into a single struct and access it using much better looking methods.

Signed-off-by: Ophestra Umiker <cat@ophivana.moe>

internal/app/start.go

@@ -62,23 +62,19 @@ func (a *app) Start() error {
 	confSockPath := path.Join(a.seal.share, "shim")
 	a.cmd = exec.Command(a.seal.toolPath, commandBuilder(shim.EnvShim+"="+confSockPath)...)
 	a.cmd.Env = []string{}
-	a.cmd.Stdin = os.Stdin
-	a.cmd.Stdout = os.Stdout
-	a.cmd.Stderr = os.Stderr
+	a.cmd.Stdin, a.cmd.Stdout, a.cmd.Stderr = os.Stdin, os.Stdout, os.Stderr
 	a.cmd.Dir = a.seal.RunDirPath
 
-	if wls, err := shim.ServeConfig(confSockPath, a.seal.sys.UID(), &shim.Payload{
+	if err := shim.ServeConfig(confSockPath, a.seal.sys.UID(), &shim.Payload{
 		Argv:  a.seal.command,
 		Exec:  shimExec,
 		Bwrap: a.seal.sys.bwrap,
-		WL:    a.seal.wlDone != nil,
+		WL:    a.seal.wl != nil,
 
 		Verbose: verbose.Get(),
-	}, a.seal.wl, a.seal.wlDone); err != nil {
+	}, a.seal.wl); err != nil {
 		return fmsg.WrapErrorSuffix(err,
-			"cannot listen on shim socket:")
-	} else {
-		a.wayland = wls
+			"cannot serve shim setup:")
 	}
 
 	// start shim
@@ -185,9 +181,8 @@ func (a *app) Wait() (int, error) {
 	verbose.Println("process", strconv.Itoa(a.cmd.Process.Pid), "exited with exit code", r)
 
 	// close wayland connection
-	if a.wayland != nil {
-		close(a.seal.wlDone)
-		if err := a.wayland.Close(); err != nil {
+	if a.seal.wl != nil {
+		if err := a.seal.wl.Close(); err != nil {
 			fmt.Println("fortify: cannot close wayland connection:", err)
 		}
 	}