exit: move final and early code to internal package

Exit cleanup state information is now stored in a dedicated struct and built up using methods of that struct.

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

8 files changed, 119 insertions, 69 deletions

diff --git a/internal/app/dbus.go b/internal/app/dbus.go
index a327e2cd..fe8039f6 100644
--- a/internal/app/dbus.go
+++ b/internal/app/dbus.go
@@ -9,8 +9,7 @@ import (
 
 	"git.ophivana.moe/cat/fortify/acl"
 	"git.ophivana.moe/cat/fortify/dbus"
-	"git.ophivana.moe/cat/fortify/internal/final"
-	"git.ophivana.moe/cat/fortify/internal/state"
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/util"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
@@ -26,7 +25,7 @@ var (
 )
 
 func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
-	a.setEnablement(state.EnableDBus)
+	a.setEnablement(internal.EnableDBus)
 
 	dbusSystem = dsg != nil
 	var binPath string
@@ -41,7 +40,7 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 	}
 
 	if b, ok := util.Which("xdg-dbus-proxy"); !ok {
-		final.Fatal("D-Bus: Did not find 'xdg-dbus-proxy' in PATH")
+		internal.Fatal("D-Bus: Did not find 'xdg-dbus-proxy' in PATH")
 	} else {
 		binPath = b
 	}
@@ -69,7 +68,7 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 		verbose.Println("D-Bus: sealing system proxy", dsg.Args(systemBus))
 	}
 	if err := p.Seal(dse, dsg); err != nil {
-		final.Fatal("D-Bus: invalid config when sealing proxy,", err)
+		internal.Fatal("D-Bus: invalid config when sealing proxy,", err)
 	}
 
 	ready := make(chan bool, 1)
@@ -80,7 +79,7 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 		verbose.Printf("Starting system bus proxy '%s' for address '%s'\n", dbusAddress[1], systemBus[0])
 	}
 	if err := p.Start(&ready); err != nil {
-		final.Fatal("D-Bus: error starting proxy,", err)
+		internal.Fatal("D-Bus: error starting proxy,", err)
 	}
 	verbose.Println("D-Bus proxy launch:", p)
 
@@ -97,24 +96,24 @@ func (a *App) ShareDBus(dse, dsg *dbus.Config, log bool) {
 	}()
 
 	// register early to enable Fatal cleanup
-	final.RegisterDBus(p, &done)
+	a.exit.SealDBus(p, &done)
 
 	if !<-ready {
-		final.Fatal("D-Bus: proxy did not start correctly")
+		internal.Fatal("D-Bus: proxy did not start correctly")
 	}
 
 	a.AppendEnv(dbusSessionBusAddress, dbusAddress[0])
 	if err := acl.UpdatePerm(sessionBus[1], a.UID(), acl.Read, acl.Write); err != nil {
-		final.Fatal(fmt.Sprintf("Error preparing D-Bus session proxy '%s':", dbusAddress[0]), err)
+		internal.Fatal(fmt.Sprintf("Error preparing D-Bus session proxy '%s':", dbusAddress[0]), err)
 	} else {
-		final.RegisterRevertPath(sessionBus[1])
+		a.exit.RegisterRevertPath(sessionBus[1])
 	}
 	if dsg != nil {
 		a.AppendEnv(dbusSystemBusAddress, dbusAddress[1])
 		if err := acl.UpdatePerm(systemBus[1], a.UID(), acl.Read, acl.Write); err != nil {
-			final.Fatal(fmt.Sprintf("Error preparing D-Bus system proxy '%s':", dbusAddress[1]), err)
+			internal.Fatal(fmt.Sprintf("Error preparing D-Bus system proxy '%s':", dbusAddress[1]), err)
 		} else {
-			final.RegisterRevertPath(systemBus[1])
+			a.exit.RegisterRevertPath(systemBus[1])
 		}
 	}
 	verbose.Printf("Session bus proxy '%s' for address '%s' configured\n", dbusAddress[0], sessionBus[0])
diff --git a/internal/app/ensure.go b/internal/app/ensure.go
index ada6349f..ed283a94 100644
--- a/internal/app/ensure.go
+++ b/internal/app/ensure.go
@@ -8,29 +8,29 @@ import (
 	"path"
 
 	"git.ophivana.moe/cat/fortify/acl"
-	"git.ophivana.moe/cat/fortify/internal/final"
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
 
 func (a *App) EnsureRunDir() {
 	if err := os.Mkdir(a.runDirPath, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
-		final.Fatal("Error creating runtime directory:", err)
+		internal.Fatal("Error creating runtime directory:", err)
 	}
 }
 
 func (a *App) EnsureRuntime() {
 	if s, err := os.Stat(a.runtimePath); err != nil {
 		if errors.Is(err, fs.ErrNotExist) {
-			final.Fatal("Runtime directory does not exist")
+			internal.Fatal("Runtime directory does not exist")
 		}
-		final.Fatal("Error accessing runtime directory:", err)
+		internal.Fatal("Error accessing runtime directory:", err)
 	} else if !s.IsDir() {
-		final.Fatal(fmt.Sprintf("Path '%s' is not a directory", a.runtimePath))
+		internal.Fatal(fmt.Sprintf("Path '%s' is not a directory", a.runtimePath))
 	} else {
 		if err = acl.UpdatePerm(a.runtimePath, a.UID(), acl.Execute); err != nil {
-			final.Fatal("Error preparing runtime directory:", err)
+			internal.Fatal("Error preparing runtime directory:", err)
 		} else {
-			final.RegisterRevertPath(a.runtimePath)
+			a.exit.RegisterRevertPath(a.runtimePath)
 		}
 		verbose.Printf("Runtime data dir '%s' configured\n", a.runtimePath)
 	}
@@ -39,7 +39,7 @@ func (a *App) EnsureRuntime() {
 func (a *App) EnsureShare() {
 	// acl is unnecessary as this directory is world executable
 	if err := os.Mkdir(a.sharePath, 0701); err != nil && !errors.Is(err, fs.ErrExist) {
-		final.Fatal("Error creating shared directory:", err)
+		internal.Fatal("Error creating shared directory:", err)
 	}
 
 	// workaround for launch method sudo
@@ -47,12 +47,12 @@ func (a *App) EnsureShare() {
 		// ensure child runtime directory (e.g. `/tmp/fortify.%d/%d.share`)
 		cr := path.Join(a.sharePath, a.Uid+".share")
 		if err := os.Mkdir(cr, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
-			final.Fatal("Error creating child runtime directory:", err)
+			internal.Fatal("Error creating child runtime directory:", err)
 		} else {
 			if err = acl.UpdatePerm(cr, a.UID(), acl.Read, acl.Write, acl.Execute); err != nil {
-				final.Fatal("Error preparing child runtime directory:", err)
+				internal.Fatal("Error preparing child runtime directory:", err)
 			} else {
-				final.RegisterRevertPath(cr)
+				a.exit.RegisterRevertPath(cr)
 			}
 			a.AppendEnv("XDG_RUNTIME_DIR", cr)
 			a.AppendEnv("XDG_SESSION_CLASS", "user")
diff --git a/internal/app/launch.go b/internal/app/launch.go
index 886e683c..b44c7785 100644
--- a/internal/app/launch.go
+++ b/internal/app/launch.go
@@ -5,11 +5,11 @@ import (
 	"encoding/base64"
 	"encoding/gob"
 	"fmt"
-	"git.ophivana.moe/cat/fortify/internal/final"
 	"os"
 	"strings"
 	"syscall"
 
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/util"
 )
 
@@ -20,7 +20,7 @@ func (a *App) launcherPayloadEnv() string {
 	enc := base64.NewEncoder(base64.StdEncoding, r)
 
 	if err := gob.NewEncoder(enc).Encode(a.command); err != nil {
-		final.Fatal("Error encoding launcher payload:", err)
+		internal.Fatal("Error encoding launcher payload:", err)
 	}
 
 	_ = enc.Close()
diff --git a/internal/app/pulse.go b/internal/app/pulse.go
index 7c360252..8b4921ed 100644
--- a/internal/app/pulse.go
+++ b/internal/app/pulse.go
@@ -8,58 +8,102 @@ import (
 	"path"
 
 	"git.ophivana.moe/cat/fortify/acl"
-	"git.ophivana.moe/cat/fortify/internal/final"
-	"git.ophivana.moe/cat/fortify/internal/state"
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/util"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
 
+const (
+	pulseServer = "PULSE_SERVER"
+	pulseCookie = "PULSE_COOKIE"
+
+	home          = "HOME"
+	xdgConfigHome = "XDG_CONFIG_HOME"
+)
+
 func (a *App) SharePulse() {
-	a.setEnablement(state.EnablePulse)
+	a.setEnablement(internal.EnablePulse)
 
 	// ensure PulseAudio directory ACL (e.g. `/run/user/%d/pulse`)
 	pulse := path.Join(a.runtimePath, "pulse")
 	pulseS := path.Join(pulse, "native")
 	if s, err := os.Stat(pulse); err != nil {
 		if !errors.Is(err, fs.ErrNotExist) {
-			final.Fatal("Error accessing PulseAudio directory:", err)
+			internal.Fatal("Error accessing PulseAudio directory:", err)
 		}
-		final.Fatal(fmt.Sprintf("PulseAudio dir '%s' not found", pulse))
+		internal.Fatal(fmt.Sprintf("PulseAudio dir '%s' not found", pulse))
 	} else {
 		// add environment variable for new process
-		a.AppendEnv(util.PulseServer, "unix:"+pulseS)
+		a.AppendEnv(pulseServer, "unix:"+pulseS)
 		if err = acl.UpdatePerm(pulse, a.UID(), acl.Execute); err != nil {
-			final.Fatal("Error preparing PulseAudio:", err)
+			internal.Fatal("Error preparing PulseAudio:", err)
 		} else {
-			final.RegisterRevertPath(pulse)
+			a.exit.RegisterRevertPath(pulse)
 		}
 
 		// ensure PulseAudio socket permission (e.g. `/run/user/%d/pulse/native`)
 		if s, err = os.Stat(pulseS); err != nil {
 			if errors.Is(err, fs.ErrNotExist) {
-				final.Fatal("PulseAudio directory found but socket does not exist")
+				internal.Fatal("PulseAudio directory found but socket does not exist")
 			}
-			final.Fatal("Error accessing PulseAudio socket:", err)
+			internal.Fatal("Error accessing PulseAudio socket:", err)
 		} else {
 			if m := s.Mode(); m&0o006 != 0o006 {
-				final.Fatal(fmt.Sprintf("Unexpected permissions on '%s':", pulseS), m)
+				internal.Fatal(fmt.Sprintf("Unexpected permissions on '%s':", pulseS), m)
 			}
 		}
 
 		// Publish current user's pulse-cookie for target user
-		pulseCookieSource := util.DiscoverPulseCookie()
+		pulseCookieSource := discoverPulseCookie()
 		pulseCookieFinal := path.Join(a.sharePath, "pulse-cookie")
-		a.AppendEnv(util.PulseCookie, pulseCookieFinal)
+		a.AppendEnv(pulseCookie, pulseCookieFinal)
 		verbose.Printf("Publishing PulseAudio cookie '%s' to '%s'\n", pulseCookieSource, pulseCookieFinal)
 		if err = util.CopyFile(pulseCookieFinal, pulseCookieSource); err != nil {
-			final.Fatal("Error copying PulseAudio cookie:", err)
+			internal.Fatal("Error copying PulseAudio cookie:", err)
 		}
 		if err = acl.UpdatePerm(pulseCookieFinal, a.UID(), acl.Read); err != nil {
-			final.Fatal("Error publishing PulseAudio cookie:", err)
+			internal.Fatal("Error publishing PulseAudio cookie:", err)
 		} else {
-			final.RegisterRevertPath(pulseCookieFinal)
+			a.exit.RegisterRevertPath(pulseCookieFinal)
 		}
 
 		verbose.Printf("PulseAudio dir '%s' configured\n", pulse)
 	}
 }
+
+// discoverPulseCookie try various standard methods to discover the current user's PulseAudio authentication cookie
+func discoverPulseCookie() string {
+	if p, ok := os.LookupEnv(pulseCookie); ok {
+		return p
+	}
+
+	if p, ok := os.LookupEnv(home); ok {
+		p = path.Join(p, ".pulse-cookie")
+		if s, err := os.Stat(p); err != nil {
+			if !errors.Is(err, fs.ErrNotExist) {
+				internal.Fatal("Error accessing PulseAudio cookie:", err)
+				// unreachable
+				return p
+			}
+		} else if !s.IsDir() {
+			return p
+		}
+	}
+
+	if p, ok := os.LookupEnv(xdgConfigHome); ok {
+		p = path.Join(p, "pulse", "cookie")
+		if s, err := os.Stat(p); err != nil {
+			if !errors.Is(err, fs.ErrNotExist) {
+				internal.Fatal("Error accessing PulseAudio cookie:", err)
+				// unreachable
+				return p
+			}
+		} else if !s.IsDir() {
+			return p
+		}
+	}
+
+	internal.Fatal(fmt.Sprintf("Cannot locate PulseAudio cookie (tried $%s, $%s/pulse/cookie, $%s/.pulse-cookie)",
+		pulseCookie, xdgConfigHome, home))
+	return ""
+}
diff --git a/internal/app/run.go b/internal/app/run.go
index d4a9e13c..cc01f487 100644
--- a/internal/app/run.go
+++ b/internal/app/run.go
@@ -3,11 +3,11 @@ package app
 import (
 	"errors"
 	"fmt"
-	"git.ophivana.moe/cat/fortify/internal/final"
 	"os"
 	"os/exec"
 	"strings"
 
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/state"
 	"git.ophivana.moe/cat/fortify/internal/util"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
@@ -52,28 +52,28 @@ func (a *App) Run() {
 	verbose.Println("Executing:", cmd)
 
 	if err := cmd.Start(); err != nil {
-		final.Fatal("Error starting process:", err)
+		internal.Fatal("Error starting process:", err)
 	}
 
-	final.RegisterEnablement(a.enablements)
+	a.exit.SealEnablements(a.enablements)
 
 	if statePath, err := state.SaveProcess(a.Uid, cmd, a.runDirPath, a.command, a.enablements); err != nil {
 		// process already started, shouldn't be fatal
 		fmt.Println("Error registering process:", err)
 	} else {
-		final.RegisterStatePath(statePath)
+		a.exit.SealStatePath(statePath)
 	}
 
 	var r int
 	if err := cmd.Wait(); err != nil {
 		var exitError *exec.ExitError
 		if !errors.As(err, &exitError) {
-			final.Fatal("Error running process:", err)
+			internal.Fatal("Error running process:", err)
 		}
 	}
 
 	verbose.Println("Process exited with exit code", r)
-	final.BeforeExit()
+	internal.BeforeExit()
 	os.Exit(r)
 }
 
@@ -101,7 +101,7 @@ func (a *App) commandBuilderSudo() (args []string) {
 
 func (a *App) commandBuilderBwrap() (args []string) {
 	// TODO: build bwrap command
-	final.Fatal("bwrap")
+	internal.Fatal("bwrap")
 	panic("unreachable")
 }
 
@@ -129,7 +129,7 @@ func (a *App) commandBuilderMachineCtl() (args []string) {
 
 	// /bin/sh -c
 	if sh, ok := util.Which("sh"); !ok {
-		final.Fatal("Did not find 'sh' in PATH")
+		internal.Fatal("Did not find 'sh' in PATH")
 	} else {
 		args = append(args, sh, "-c")
 	}
@@ -147,9 +147,9 @@ func (a *App) commandBuilderMachineCtl() (args []string) {
 	innerCommand.WriteString("; ")
 
 	if executable, err := os.Executable(); err != nil {
-		final.Fatal("Error reading executable path:", err)
+		internal.Fatal("Error reading executable path:", err)
 	} else {
-		if a.enablements.Has(state.EnableDBus) {
+		if a.enablements.Has(internal.EnableDBus) {
 			innerCommand.WriteString(dbusSessionBusAddress + "=" + "'" + dbusAddress[0] + "' ")
 			if dbusSystem {
 				innerCommand.WriteString(dbusSystemBusAddress + "=" + "'" + dbusAddress[1] + "' ")
diff --git a/internal/app/setup.go b/internal/app/setup.go
index 8d6eb881..c13468a0 100644
--- a/internal/app/setup.go
+++ b/internal/app/setup.go
@@ -8,7 +8,7 @@ import (
 	"path"
 	"strconv"
 
-	"git.ophivana.moe/cat/fortify/internal/state"
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/util"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
@@ -22,6 +22,8 @@ type App struct {
 	env     []string // modified via AppendEnv
 	command []string // set on initialisation
 
+	exit *internal.ExitState // assigned
+
 	launchOptionText string // set on initialisation
 	launchOption     uint8  // assigned
 
@@ -30,8 +32,8 @@ type App struct {
 	runDirPath  string // assigned
 	toolPath    string // assigned
 
-	enablements state.Enablements // set via setEnablement
-	*user.User                    // assigned
+	enablements internal.Enablements // set via setEnablement
+	*user.User                       // assigned
 
 	// absolutely *no* method of this type is thread-safe
 	// so don't treat it as if it is
@@ -45,7 +47,7 @@ func (a *App) RunDir() string {
 	return a.runDirPath
 }
 
-func (a *App) setEnablement(e state.Enablement) {
+func (a *App) setEnablement(e internal.Enablement) {
 	if a.enablements.Has(e) {
 		panic("enablement " + e.String() + " set twice")
 	}
@@ -53,6 +55,13 @@ func (a *App) setEnablement(e state.Enablement) {
 	a.enablements |= e.Mask()
 }
 
+func (a *App) SealExit(exit *internal.ExitState) {
+	if a.exit != nil {
+		panic("application exit state sealed twice")
+	}
+	a.exit = exit
+}
+
 func New(userName string, args []string, launchOptionText string) *App {
 	a := &App{
 		command:          args,
@@ -96,7 +105,7 @@ func New(userName string, args []string, launchOptionText string) *App {
 	}
 
 	verbose.Println("Running as user", a.Username, "("+a.Uid+"),", "command:", a.command)
-	if util.SdBootedV {
+	if internal.SdBootedV {
 		verbose.Println("System booted with systemd as init system (PID 1).")
 	}
 
@@ -120,7 +129,7 @@ func New(userName string, args []string, launchOptionText string) *App {
 		}
 	case "systemd":
 		a.launchOption = LaunchMethodMachineCtl
-		if !util.SdBootedV {
+		if !internal.SdBootedV {
 			fmt.Println("System has not been booted with systemd as init system (PID 1).")
 			os.Exit(1)
 		}
diff --git a/internal/app/wayland.go b/internal/app/wayland.go
index 3b12e3ec..33ed9914 100644
--- a/internal/app/wayland.go
+++ b/internal/app/wayland.go
@@ -6,8 +6,7 @@ import (
 	"path"
 
 	"git.ophivana.moe/cat/fortify/acl"
-	"git.ophivana.moe/cat/fortify/internal/final"
-	"git.ophivana.moe/cat/fortify/internal/state"
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 )
 
@@ -17,19 +16,19 @@ const (
 )
 
 func (a *App) ShareWayland() {
-	a.setEnablement(state.EnableWayland)
+	a.setEnablement(internal.EnableWayland)
 
 	// ensure Wayland socket ACL (e.g. `/run/user/%d/wayland-%d`)
 	if w, ok := os.LookupEnv(waylandDisplay); !ok {
-		final.Fatal("Wayland: WAYLAND_DISPLAY not set")
+		internal.Fatal("Wayland: WAYLAND_DISPLAY not set")
 	} else {
 		// add environment variable for new process
 		wp := path.Join(a.runtimePath, w)
 		a.AppendEnv(waylandDisplay, wp)
 		if err := acl.UpdatePerm(wp, a.UID(), acl.Read, acl.Write, acl.Execute); err != nil {
-			final.Fatal(fmt.Sprintf("Error preparing Wayland '%s':", w), err)
+			internal.Fatal(fmt.Sprintf("Error preparing Wayland '%s':", w), err)
 		} else {
-			final.RegisterRevertPath(wp)
+			a.exit.RegisterRevertPath(wp)
 		}
 		verbose.Printf("Wayland socket '%s' configured\n", w)
 	}
diff --git a/internal/app/x.go b/internal/app/x.go
index f198fee3..16b3d95c 100644
--- a/internal/app/x.go
+++ b/internal/app/x.go
@@ -4,8 +4,7 @@ import (
 	"fmt"
 	"os"
 
-	"git.ophivana.moe/cat/fortify/internal/final"
-	"git.ophivana.moe/cat/fortify/internal/state"
+	"git.ophivana.moe/cat/fortify/internal"
 	"git.ophivana.moe/cat/fortify/internal/verbose"
 	"git.ophivana.moe/cat/fortify/xcb"
 )
@@ -13,20 +12,20 @@ import (
 const display = "DISPLAY"
 
 func (a *App) ShareX() {
-	a.setEnablement(state.EnableX)
+	a.setEnablement(internal.EnableX)
 
 	// discovery X11 and grant user permission via the `ChangeHosts` command
 	if d, ok := os.LookupEnv(display); !ok {
-		final.Fatal("X11: DISPLAY not set")
+		internal.Fatal("X11: DISPLAY not set")
 	} else {
 		// add environment variable for new process
 		a.AppendEnv(display, d)
 
 		verbose.Printf("X11: Adding XHost entry SI:localuser:%s to display '%s'\n", a.Username, d)
 		if err := xcb.ChangeHosts(xcb.HostModeInsert, xcb.FamilyServerInterpreted, "localuser\x00"+a.Username); err != nil {
-			final.Fatal(fmt.Sprintf("Error adding XHost entry to '%s':", d), err)
+			internal.Fatal(fmt.Sprintf("Error adding XHost entry to '%s':", d), err)
 		} else {
-			final.XcbActionComplete()
+			a.exit.XcbActionComplete()
 		}
 	}
 }