fmsg: produce all output through fmsg

The behaviour of print functions from package fmt is not thread safe. Functions provided by fmsg wrap around Logger methods. This makes prefix much cleaner and makes it easy to deal with future changes to logging.

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

config.go

@@ -9,6 +9,7 @@ import (
 	"git.ophivana.moe/security/fortify/dbus"
 	"git.ophivana.moe/security/fortify/internal"
 	"git.ophivana.moe/security/fortify/internal/app"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 	"git.ophivana.moe/security/fortify/internal/system"
 )
 
@@ -60,7 +61,7 @@ func init() {
 func tryTemplate() {
 	if printTemplate {
 		if s, err := json.MarshalIndent(app.Template(), "", "  "); err != nil {
-			fatalf("cannot generate template: %v", err)
+			fmsg.Fatalf("cannot generate template: %v", err)
 			panic("unreachable")
 		} else {
 			fmt.Println(string(s))
@@ -77,10 +78,10 @@ func loadConfig() *app.Config {
 		// config from file
 		c := new(app.Config)
 		if f, err := os.Open(confPath); err != nil {
-			fatalf("cannot access config file '%s': %s\n", confPath, err)
+			fmsg.Fatalf("cannot access config file %q: %s", confPath, err)
 			panic("unreachable")
 		} else if err = json.NewDecoder(f).Decode(&c); err != nil {
-			fatalf("cannot parse config file '%s': %s\n", confPath, err)
+			fmsg.Fatalf("cannot parse config file %q: %s", confPath, err)
 			panic("unreachable")
 		} else {
 			return c
@@ -110,7 +111,7 @@ func configFromFlags() (config *app.Config) {
 			config.Confinement.SessionBus = dbus.NewConfig(dbusID, true, mpris)
 		} else {
 			if c, err := dbus.NewConfigFromFile(dbusConfigSession); err != nil {
-				fatalf("cannot load session bus proxy config from %q: %s\n", dbusConfigSession, err)
+				fmsg.Fatalf("cannot load session bus proxy config from %q: %s", dbusConfigSession, err)
 			} else {
 				config.Confinement.SessionBus = c
 			}
@@ -119,7 +120,7 @@ func configFromFlags() (config *app.Config) {
 		// system bus proxy is optional
 		if dbusConfigSystem != "nil" {
 			if c, err := dbus.NewConfigFromFile(dbusConfigSystem); err != nil {
-				fatalf("cannot load system bus proxy config from %q: %s\n", dbusConfigSystem, err)
+				fmsg.Fatalf("cannot load system bus proxy config from %q: %s", dbusConfigSystem, err)
 			} else {
 				config.Confinement.SystemBus = c
 			}

error.go

@@ -3,7 +3,6 @@ package main
 import (
 	"errors"
 	"fmt"
-	"os"
 
 	"git.ophivana.moe/security/fortify/internal/app"
 	"git.ophivana.moe/security/fortify/internal/fmsg"
@@ -12,13 +11,13 @@ import (
 func logWaitError(err error) {
 	var e *fmsg.BaseError
 	if !fmsg.AsBaseError(err, &e) {
-		fmt.Println("fortify: wait failed:", err)
+		fmsg.Println("wait failed:", err)
 	} else {
 		// Wait only returns either *app.ProcessError or *app.StateStoreError wrapped in a *app.BaseError
 		var se *app.StateStoreError
 		if !errors.As(err, &se) {
 			// does not need special handling
-			fmt.Print("fortify: " + e.Message())
+			fmsg.Print(e.Message())
 		} else {
 			// inner error are either unwrapped store errors
 			// or joined errors returned by *appSealTx revert
@@ -26,7 +25,7 @@ func logWaitError(err error) {
 			var ej app.RevertCompoundError
 			if !errors.As(se.InnerErr, &ej) {
 				// does not require special handling
-				fmt.Print("fortify: " + e.Message())
+				fmsg.Print(e.Message())
 			} else {
 				errs := ej.Unwrap()
 
@@ -35,10 +34,10 @@ func logWaitError(err error) {
 					var eb *fmsg.BaseError
 					if !errors.As(ei, &eb) {
 						// unreachable
-						fmt.Println("fortify: invalid error type returned by revert:", ei)
+						fmsg.Println("invalid error type returned by revert:", ei)
 					} else {
 						// print inner *app.BaseError message
-						fmt.Print("fortify: " + eb.Message())
+						fmsg.Print(eb.Message())
 					}
 				}
 			}
@@ -50,13 +49,8 @@ func logBaseError(err error, message string) {
 	var e *fmsg.BaseError
 
 	if fmsg.AsBaseError(err, &e) {
-		fmt.Print("fortify: " + e.Message())
+		fmsg.Print(e.Message())
 	} else {
 		fmt.Println(message, err)
 	}
 }
-
-func fatalf(format string, a ...any) {
-	fmt.Printf("fortify: "+format, a...)
-	os.Exit(1)
-}

internal/app/launch.machinectl.go

@@ -4,7 +4,7 @@ import (
 	"os/exec"
 	"strings"
 
-	"git.ophivana.moe/security/fortify/internal/verbose"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 )
 
 func (a *app) commandBuilderMachineCtl(shimEnv string) (args []string) {
@@ -14,7 +14,7 @@ func (a *app) commandBuilderMachineCtl(shimEnv string) (args []string) {
 	args = append(args, "shell", "--uid="+a.seal.sys.user.Username)
 
 	// --quiet
-	if !verbose.Get() {
+	if !fmsg.Verbose() {
 		args = append(args, "--quiet")
 	}
 

internal/app/launch.sudo.go

@@ -3,7 +3,7 @@ package app
 import (
 	"os"
 
-	"git.ophivana.moe/security/fortify/internal/verbose"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 )
 
 const (
@@ -18,7 +18,7 @@ func (a *app) commandBuilderSudo(shimEnv string) (args []string) {
 
 	// -A?
 	if _, ok := os.LookupEnv(sudoAskPass); ok {
-		verbose.Printf("%s set, adding askpass flag\n", sudoAskPass)
+		fmsg.VPrintln(sudoAskPass, "set, adding askpass flag")
 		args = append(args, "-A")
 	}
 

internal/app/seal.go

@@ -14,7 +14,6 @@ import (
 	"git.ophivana.moe/security/fortify/internal/shim"
 	"git.ophivana.moe/security/fortify/internal/state"
 	"git.ophivana.moe/security/fortify/internal/system"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 const (
@@ -152,7 +151,7 @@ func (a *app) Seal(config *Config) error {
 
 	// map sandbox config to bwrap
 	if config.Confinement.Sandbox == nil {
-		verbose.Println("sandbox configuration not supplied, PROCEED WITH CAUTION")
+		fmsg.VPrintln("sandbox configuration not supplied, PROCEED WITH CAUTION")
 
 		// permissive defaults
 		conf := &SandboxConfig{
@@ -242,7 +241,7 @@ func (a *app) Seal(config *Config) error {
 	}
 
 	// verbose log seal information
-	verbose.Println("created application seal as user",
+	fmsg.VPrintln("created application seal as user",
 		seal.sys.user.Username, "("+seal.sys.user.Uid+"),",
 		"method:", config.Method+",",
 		"launcher:", seal.toolPath+",",

internal/app/start.go

@@ -7,7 +7,6 @@ import (
 	"os/exec"
 	"path"
 	"path/filepath"
-	"strconv"
 	"strings"
 	"time"
 
@@ -16,7 +15,6 @@ import (
 	"git.ophivana.moe/security/fortify/internal/shim"
 	"git.ophivana.moe/security/fortify/internal/state"
 	"git.ophivana.moe/security/fortify/internal/system"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 // Start starts the fortified child
@@ -71,14 +69,14 @@ func (a *app) Start() error {
 		Bwrap: a.seal.sys.bwrap,
 		WL:    a.seal.wl != nil,
 
-		Verbose: verbose.Get(),
+		Verbose: fmsg.Verbose(),
 	}, a.seal.wl); err != nil {
 		return fmsg.WrapErrorSuffix(err,
 			"cannot serve shim setup:")
 	}
 
 	// start shim
-	verbose.Println("starting shim as target user:", a.cmd)
+	fmsg.VPrintln("starting shim as target user:", a.cmd)
 	if err := a.cmd.Start(); err != nil {
 		return fmsg.WrapErrorSuffix(err,
 			"cannot start process:")
@@ -178,12 +176,12 @@ func (a *app) Wait() (int, error) {
 		r = a.cmd.ProcessState.ExitCode()
 	}
 
-	verbose.Println("process", strconv.Itoa(a.cmd.Process.Pid), "exited with exit code", r)
+	fmsg.VPrintf("process %d exited with exit code %d", a.cmd.Process.Pid, r)
 
 	// close wayland connection
 	if a.seal.wl != nil {
 		if err := a.seal.wl.Close(); err != nil {
-			fmt.Println("fortify: cannot close wayland connection:", err)
+			fmsg.Println("cannot close wayland connection:", err)
 		}
 	}
 
@@ -205,10 +203,10 @@ func (a *app) Wait() (int, error) {
 			} else {
 				if l := len(states); l == 0 {
 					// cleanup globals as the final launcher
-					verbose.Println("no other launchers active, will clean up globals")
+					fmsg.VPrintln("no other launchers active, will clean up globals")
 					ec.Set(system.User)
 				} else {
-					verbose.Printf("found %d active launchers, cleaning up without globals\n", l)
+					fmsg.VPrintf("found %d active launchers, cleaning up without globals", l)
 				}
 
 				// accumulate capabilities of other launchers
@@ -222,7 +220,7 @@ func (a *app) Wait() (int, error) {
 					ec.Set(i)
 				}
 			}
-			if verbose.Get() {
+			if fmsg.Verbose() {
 				labels := make([]string, 0, system.ELen+1)
 				for i := system.Enablement(0); i < system.Enablement(system.ELen+2); i++ {
 					if ec.Has(i) {
@@ -230,7 +228,7 @@ func (a *app) Wait() (int, error) {
 					}
 				}
 				if len(labels) > 0 {
-					verbose.Println("reverting operations labelled", strings.Join(labels, ", "))
+					fmsg.VPrintln("reverting operations labelled", strings.Join(labels, ", "))
 				}
 			}
 

internal/early.go

@@ -2,9 +2,10 @@ package internal
 
 import (
 	"errors"
-	"fmt"
 	"io/fs"
 	"os"
+
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 )
 
 const (
@@ -13,7 +14,7 @@ const (
 
 var SdBootedV = func() bool {
 	if v, err := SdBooted(); err != nil {
-		fmt.Println("warn: read systemd marker:", err)
+		fmsg.Println("cannot read systemd marker:", err)
 		return false
 	} else {
 		return v

internal/environ.go

@@ -1,13 +1,12 @@
 package internal
 
 import (
-	"fmt"
 	"os"
 	"path"
 	"strconv"
 	"sync"
 
-	"git.ophivana.moe/security/fortify/internal/verbose"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 )
 
 // state that remain constant for the lifetime of the process
@@ -37,16 +36,16 @@ func copySC() {
 		SharePath: path.Join(os.TempDir(), "fortify."+strconv.Itoa(os.Geteuid())),
 	}
 
-	verbose.Println("process share directory at", sc.SharePath)
+	fmsg.VPrintf("process share directory at %q", sc.SharePath)
 
 	// runtimePath, runDirPath
 	if r, ok := os.LookupEnv(xdgRuntimeDir); !ok {
-		fmt.Println("Env variable", xdgRuntimeDir, "unset")
+		fmsg.Println("variable", xdgRuntimeDir, "unset")
 		os.Exit(1)
 	} else {
 		sc.RuntimePath = r
 		sc.RunDirPath = path.Join(sc.RuntimePath, "fortify")
-		verbose.Println("XDG runtime directory at", sc.RunDirPath)
+		fmsg.VPrintf("XDG runtime directory at %q", sc.RunDirPath)
 	}
 
 	scVal = sc

internal/fmsg/fmsg.go

@@ -1,2 +1,41 @@
 // Package fmsg provides various functions for output messages.
 package fmsg
+
+import (
+	"log"
+	"os"
+	"sync/atomic"
+)
+
+var (
+	std  = log.New(os.Stdout, "fortify: ", 0)
+	warn = log.New(os.Stderr, "fortify: ", 0)
+
+	verbose = new(atomic.Bool)
+)
+
+func SetPrefix(prefix string) {
+	prefix += ": "
+	std.SetPrefix(prefix)
+	warn.SetPrefix(prefix)
+}
+
+func Print(v ...any) {
+	warn.Print(v...)
+}
+
+func Printf(format string, v ...any) {
+	warn.Printf(format, v...)
+}
+
+func Println(v ...any) {
+	warn.Println(v...)
+}
+
+func Fatal(v ...any) {
+	warn.Fatal(v...)
+}
+
+func Fatalf(format string, v ...any) {
+	warn.Fatalf(format, v...)
+}

internal/fmsg/verbose.go

@@ -0,0 +1,21 @@
+package fmsg
+
+func Verbose() bool {
+	return verbose.Load()
+}
+
+func SetVerbose(v bool) {
+	verbose.Store(v)
+}
+
+func VPrintf(format string, v ...any) {
+	if verbose.Load() {
+		std.Printf(format, v...)
+	}
+}
+
+func VPrintln(v ...any) {
+	if verbose.Load() {
+		std.Println(v...)
+	}
+}

internal/init/main.go

@@ -4,7 +4,6 @@ import (
 	"encoding/gob"
 	"errors"
 	"flag"
-	"fmt"
 	"os"
 	"os/exec"
 	"os/signal"
@@ -13,7 +12,7 @@ import (
 	"syscall"
 	"time"
 
-	"git.ophivana.moe/security/fortify/internal/verbose"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 )
 
 const (
@@ -25,49 +24,46 @@ const (
 // proceed with caution!
 
 func doInit(fd uintptr) {
+	fmsg.SetPrefix("init")
+
 	// re-exec
 	if len(os.Args) > 0 && os.Args[0] != "fortify" && path.IsAbs(os.Args[0]) {
 		if err := syscall.Exec(os.Args[0], []string{"fortify", "init"}, os.Environ()); err != nil {
-			fmt.Println("fortify-init: cannot re-exec self:", err)
+			fmsg.Println("cannot re-exec self:", err)
 			// continue anyway
 		}
 	}
 
-	verbose.Prefix = "fortify-init:"
-
 	var payload Payload
 	p := os.NewFile(fd, "config-stream")
 	if p == nil {
-		fmt.Println("fortify-init: invalid config descriptor")
+		fmsg.Fatal("invalid config descriptor")
-		os.Exit(1)
 	}
 	if err := gob.NewDecoder(p).Decode(&payload); err != nil {
-		fmt.Println("fortify-init: cannot decode init payload:", err)
+		fmsg.Fatal("cannot decode init payload:", err)
-		os.Exit(1)
 	} else {
 		// sharing stdout with parent
 		// USE WITH CAUTION
-		verbose.Set(payload.Verbose)
+		fmsg.SetVerbose(payload.Verbose)
 
 		// child does not need to see this
 		if err = os.Unsetenv(EnvInit); err != nil {
-			fmt.Println("fortify-init: cannot unset", EnvInit+":", err)
+			fmsg.Println("cannot unset", EnvInit+":", err)
 			// not fatal
 		} else {
-			verbose.Println("received configuration")
+			fmsg.VPrintln("received configuration")
 		}
 	}
 
 	// close config fd
 	if err := p.Close(); err != nil {
-		fmt.Println("fortify-init: cannot close config fd:", err)
+		fmsg.Println("cannot close config fd:", err)
 		// not fatal
 	}
 
 	// die with parent
 	if _, _, errno := syscall.RawSyscall(syscall.SYS_PRCTL, syscall.PR_SET_PDEATHSIG, uintptr(syscall.SIGKILL), 0); errno != 0 {
-		fmt.Println("fortify-init: prctl(PR_SET_PDEATHSIG, SIGKILL):", errno.Error())
+		fmsg.Fatal("prctl(PR_SET_PDEATHSIG, SIGKILL):", errno.Error())
-		os.Exit(1)
 	}
 
 	cmd := exec.Command(payload.Argv0)
@@ -84,8 +80,7 @@ func doInit(fd uintptr) {
 	}
 
 	if err := cmd.Start(); err != nil {
-		fmt.Printf("fortify-init: cannot start %q: %v", payload.Argv0, err)
+		fmsg.Fatalf("cannot start %q: %v", payload.Argv0, err)
-		os.Exit(1)
 	}
 
 	sig := make(chan os.Signal, 2)
@@ -121,7 +116,7 @@ func doInit(fd uintptr) {
 			}
 		}
 		if !errors.Is(err, syscall.ECHILD) {
-			fmt.Println("fortify-init: unexpected wait4 response:", err)
+			fmsg.Println("unexpected wait4 response:", err)
 		}
 
 		close(done)
@@ -133,7 +128,7 @@ func doInit(fd uintptr) {
 	for {
 		select {
 		case s := <-sig:
-			verbose.Println("received", s.String())
+			fmsg.VPrintln("received", s.String())
 			os.Exit(0)
 		case w := <-info:
 			if w.wpid == cmd.Process.Pid {
@@ -154,7 +149,7 @@ func doInit(fd uintptr) {
 		case <-done:
 			os.Exit(r)
 		case <-timeout:
-			fmt.Println("fortify-init: timeout exceeded waiting for lingering processes")
+			fmsg.Println("timeout exceeded waiting for lingering processes")
 			os.Exit(r)
 		}
 	}
@@ -169,8 +164,7 @@ func Try() {
 	if args := flag.Args(); len(args) == 1 && args[0] == "init" {
 		if s, ok := os.LookupEnv(EnvInit); ok {
 			if fd, err := strconv.Atoi(s); err != nil {
-				fmt.Printf("fortify-init: cannot parse %q: %v", s, err)
+				fmsg.Fatalf("cannot parse %q: %v", s, err)
-				os.Exit(1)
 			} else {
 				doInit(uintptr(fd))
 			}

internal/shim/main.go

@@ -4,7 +4,6 @@ import (
 	"encoding/gob"
 	"errors"
 	"flag"
-	"fmt"
 	"net"
 	"os"
 	"path"
@@ -12,29 +11,29 @@ import (
 	"syscall"
 
 	"git.ophivana.moe/security/fortify/helper"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 	init0 "git.ophivana.moe/security/fortify/internal/init"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 // everything beyond this point runs as target user
 // proceed with caution!
 
 func doShim(socket string) {
+	fmsg.SetPrefix("shim")
+
 	// re-exec
 	if len(os.Args) > 0 && os.Args[0] != "fortify" && path.IsAbs(os.Args[0]) {
 		if err := syscall.Exec(os.Args[0], []string{"fortify", "shim"}, os.Environ()); err != nil {
-			fmt.Println("fortify-shim: cannot re-exec self:", err)
+			fmsg.Println("cannot re-exec self:", err)
 			// continue anyway
 		}
 	}
 
-	verbose.Prefix = "fortify-shim:"
-
 	// dial setup socket
 	var conn *net.UnixConn
 	if c, err := net.DialUnix("unix", nil, &net.UnixAddr{Name: socket, Net: "unix"}); err != nil {
-		fmt.Println("fortify-shim: cannot dial setup socket:", err)
+		fmsg.Fatal("cannot dial setup socket:", err)
-		os.Exit(1)
+		panic("unreachable")
 	} else {
 		conn = c
 	}
@@ -42,25 +41,22 @@ func doShim(socket string) {
 	// decode payload gob stream
 	var payload Payload
 	if err := gob.NewDecoder(conn).Decode(&payload); err != nil {
-		fmt.Println("fortify-shim: cannot decode shim payload:", err)
+		fmsg.Fatal("cannot decode shim payload:", err)
-		os.Exit(1)
 	} else {
 		// sharing stdout with parent
 		// USE WITH CAUTION
-		verbose.Set(payload.Verbose)
+		fmsg.SetVerbose(payload.Verbose)
 	}
 
 	if payload.Bwrap == nil {
-		fmt.Println("fortify-shim: bwrap config not supplied")
+		fmsg.Fatal("bwrap config not supplied")
-		os.Exit(1)
 	}
 
 	// receive wayland fd over socket
 	wfd := -1
 	if payload.WL {
 		if fd, err := receiveWLfd(conn); err != nil {
-			fmt.Println("fortify-shim: cannot receive wayland fd:", err)
+			fmsg.Fatal("cannot receive wayland fd:", err)
-			os.Exit(1)
 		} else {
 			wfd = fd
 		}
@@ -68,7 +64,7 @@ func doShim(socket string) {
 
 	// close setup socket
 	if err := conn.Close(); err != nil {
-		fmt.Println("fortify-shim: cannot close setup socket:", err)
+		fmsg.Println("cannot close setup socket:", err)
 		// not fatal
 	}
 
@@ -83,8 +79,7 @@ func doShim(socket string) {
 		// no argv, look up shell instead
 		var ok bool
 		if ic.Argv0, ok = os.LookupEnv("SHELL"); !ok {
-			fmt.Println("fortify-shim: no command was specified and $SHELL was unset")
+			fmsg.Fatal("no command was specified and $SHELL was unset")
-			os.Exit(1)
 		}
 
 		ic.Argv = []string{ic.Argv0}
@@ -106,41 +101,37 @@ func doShim(socket string) {
 
 	// share config pipe
 	if r, w, err := os.Pipe(); err != nil {
-		fmt.Println("fortify-shim: cannot pipe:", err)
+		fmsg.Fatal("cannot pipe:", err)
-		os.Exit(1)
 	} else {
 		conf.SetEnv[init0.EnvInit] = strconv.Itoa(3 + len(extraFiles))
 		extraFiles = append(extraFiles, r)
 
-		verbose.Println("transmitting config to init")
+		fmsg.VPrintln("transmitting config to init")
 		go func() {
 			// stream config to pipe
 			if err = gob.NewEncoder(w).Encode(&ic); err != nil {
-				fmt.Println("fortify-shim: cannot transmit init config:", err)
+				fmsg.Fatal("cannot transmit init config:", err)
-				os.Exit(1)
 			}
 		}()
 	}
 
 	helper.BubblewrapName = payload.Exec[1] // resolved bwrap path by parent
 	if b, err := helper.NewBwrap(conf, nil, payload.Exec[0], func(int, int) []string { return []string{"init"} }); err != nil {
-		fmt.Println("fortify-shim: malformed sandbox config:", err)
+		fmsg.Fatal("malformed sandbox config:", err)
-		os.Exit(1)
 	} else {
 		cmd := b.Unwrap()
 		cmd.Stdin, cmd.Stdout, cmd.Stderr = os.Stdin, os.Stdout, os.Stderr
 		cmd.ExtraFiles = extraFiles
 
-		if verbose.Get() {
+		if fmsg.Verbose() {
-			verbose.Println("bwrap args:", conf.Args())
+			fmsg.VPrintln("bwrap args:", conf.Args())
 		}
 
 		// run and pass through exit code
 		if err = b.Start(); err != nil {
-			fmt.Println("fortify-shim: cannot start target process:", err)
+			fmsg.Fatal("cannot start target process:", err)
-			os.Exit(1)
 		} else if err = b.Wait(); err != nil {
-			verbose.Println("wait:", err)
+			fmsg.VPrintln("wait:", err)
 		}
 		if b.Unwrap().ProcessState != nil {
 			os.Exit(b.Unwrap().ProcessState.ExitCode())

internal/shim/parent.go

@@ -3,13 +3,12 @@ package shim
 import (
 	"encoding/gob"
 	"errors"
-	"fmt"
 	"net"
 	"os"
 	"syscall"
 
 	"git.ophivana.moe/security/fortify/acl"
-	"git.ophivana.moe/security/fortify/internal/verbose"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 )
 
 // called in the parent process
@@ -19,7 +18,7 @@ func ServeConfig(socket string, uid int, payload *Payload, wl *Wayland) error {
 		if f, err := net.DialUnix("unix", nil, &net.UnixAddr{Name: wl.Path, Net: "unix"}); err != nil {
 			return err
 		} else {
-			verbose.Println("connected to wayland at", wl)
+			fmsg.VPrintf("connected to wayland at %q", wl.Path)
 			wl.UnixConn = f
 		}
 	}
@@ -27,18 +26,18 @@ func ServeConfig(socket string, uid int, payload *Payload, wl *Wayland) error {
 	if c, err := net.ListenUnix("unix", &net.UnixAddr{Name: socket, Net: "unix"}); err != nil {
 		return err
 	} else {
-		verbose.Println("configuring shim on socket", socket)
+		fmsg.VPrintf("configuring shim on socket %q", socket)
 		if err = acl.UpdatePerm(socket, uid, acl.Read, acl.Write, acl.Execute); err != nil {
-			fmt.Println("fortify: cannot change permissions of shim setup socket:", err)
+			fmsg.Println("cannot change permissions of shim setup socket:", err)
 		}
 
 		go func() {
 			var conn *net.UnixConn
 			if conn, err = c.AcceptUnix(); err != nil {
-				fmt.Println("fortify: cannot accept connection from shim:", err)
+				fmsg.Println("cannot accept connection from shim:", err)
 			} else {
 				if err = gob.NewEncoder(conn).Encode(*payload); err != nil {
-					fmt.Println("fortify: cannot stream shim payload:", err)
+					fmsg.Println("cannot stream shim payload:", err)
 					_ = os.Remove(socket)
 					return
 				}
@@ -47,23 +46,23 @@ func ServeConfig(socket string, uid int, payload *Payload, wl *Wayland) error {
 					// get raw connection
 					var rc syscall.RawConn
 					if rc, err = wl.SyscallConn(); err != nil {
-						fmt.Println("fortify: cannot obtain raw wayland connection:", err)
+						fmsg.Println("cannot obtain raw wayland connection:", err)
 						return
 					} else {
 						go func() {
 							// pass wayland socket fd
 							if err = rc.Control(func(fd uintptr) {
 								if _, _, err = conn.WriteMsgUnix(nil, syscall.UnixRights(int(fd)), nil); err != nil {
-									fmt.Println("fortify: cannot pass wayland connection to shim:", err)
+									fmsg.Println("cannot pass wayland connection to shim:", err)
 									return
 								}
 								_ = conn.Close()
 
 								// block until shim exits
 								<-wl.done
-								verbose.Println("releasing wayland connection")
+								fmsg.VPrintln("releasing wayland connection")
 							}); err != nil {
-								fmt.Println("fortify: cannot obtain wayland connection fd:", err)
+								fmsg.Println("cannot obtain wayland connection fd:", err)
 							}
 						}()
 					}
@@ -72,10 +71,10 @@ func ServeConfig(socket string, uid int, payload *Payload, wl *Wayland) error {
 				}
 			}
 			if err = c.Close(); err != nil {
-				fmt.Println("fortify: cannot close shim socket:", err)
+				fmsg.Println("cannot close shim socket:", err)
 			}
 			if err = os.Remove(socket); err != nil && !errors.Is(err, os.ErrNotExist) {
-				fmt.Println("fortify: cannot remove dangling shim socket:", err)
+				fmsg.Println("cannot remove dangling shim socket:", err)
 			}
 		}()
 		return nil

internal/state/print.go

@@ -10,8 +10,8 @@ import (
 	"text/tabwriter"
 	"time"
 
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 	"git.ophivana.moe/security/fortify/internal/system"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 // MustPrintLauncherStateSimpleGlobal prints active launcher states of all simple stores
@@ -21,19 +21,19 @@ func MustPrintLauncherStateSimpleGlobal(w **tabwriter.Writer, runDir string) {
 
 	// read runtime directory to get all UIDs
 	if dirs, err := os.ReadDir(path.Join(runDir, "state")); err != nil && !errors.Is(err, os.ErrNotExist) {
-		fmt.Println("cannot read runtime directory:", err)
+		fmsg.Println("cannot read runtime directory:", err)
 		os.Exit(1)
 	} else {
 		for _, e := range dirs {
 			// skip non-directories
 			if !e.IsDir() {
-				verbose.Println("skipped non-directory entry", e.Name())
+				fmsg.VPrintf("skipped non-directory entry %q", e.Name())
 				continue
 			}
 
 			// skip non-numerical names
 			if _, err = strconv.Atoi(e.Name()); err != nil {
-				verbose.Println("skipped non-uid entry", e.Name())
+				fmsg.VPrintf("skipped non-uid entry %q", e.Name())
 				continue
 			}
 
@@ -45,7 +45,7 @@ func MustPrintLauncherStateSimpleGlobal(w **tabwriter.Writer, runDir string) {
 
 			// mustPrintLauncherState causes store activity so store needs to be closed
 			if err = s.Close(); err != nil {
-				fmt.Printf("warn: error closing store for user %s: %s\n", e.Name(), err)
+				fmsg.Printf("cannot close store for user %q: %s", e.Name(), err)
 			}
 		}
 	}
@@ -67,7 +67,7 @@ func (s *simpleStore) mustPrintLauncherState(w **tabwriter.Writer, now time.Time
 				*w = tabwriter.NewWriter(os.Stdout, 0, 1, 4, ' ', 0)
 
 				// write header when initialising
-				if !verbose.Get() {
+				if !fmsg.Verbose() {
 					_, _ = fmt.Fprintln(*w, "\tUID\tPID\tUptime\tEnablements\tMethod\tCommand")
 				} else {
 					// argv is emitted in body when verbose
@@ -96,7 +96,7 @@ func (s *simpleStore) mustPrintLauncherState(w **tabwriter.Writer, now time.Time
 					ets.WriteString("(No enablements)")
 				}
 
-				if !verbose.Get() {
+				if !fmsg.Verbose() {
 					_, _ = fmt.Fprintf(*w, "\t%s\t%d\t%s\t%s\t%s\t%s\n",
 						s.path[len(s.path)-1], state.PID, now.Sub(state.Time).Round(time.Second).String(), strings.TrimPrefix(ets.String(), ", "), state.Method,
 						state.Command)
@@ -110,15 +110,15 @@ func (s *simpleStore) mustPrintLauncherState(w **tabwriter.Writer, now time.Time
 			return nil
 		}()
 	}); err != nil {
-		fmt.Printf("cannot perform action on store '%s': %s\n", path.Join(s.path...), err)
+		fmsg.Printf("cannot perform action on store %q: %s", path.Join(s.path...), err)
 		if !ok {
-			fmt.Println("warn: store faulted before printing")
+			fmsg.Println("store faulted before printing")
 			os.Exit(1)
 		}
 	}
 
 	if innerErr != nil {
-		fmt.Printf("cannot print launcher state for store '%s': %s\n", path.Join(s.path...), innerErr)
+		fmsg.Printf("cannot print launcher state for store %q: %s", path.Join(s.path...), innerErr)
 		os.Exit(1)
 	}
 }

internal/system/acl.go

@@ -6,7 +6,6 @@ import (
 
 	"git.ophivana.moe/security/fortify/acl"
 	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 // UpdatePerm appends an ephemeral acl update Op.
@@ -33,18 +32,20 @@ func (a *ACL) Type() Enablement {
 }
 
 func (a *ACL) apply(sys *I) error {
-	verbose.Println("applying ACL", a, "uid:", sys.uid, "type:", TypeString(a.et), "path:", a.path)
+	fmsg.VPrintf("applying ACL %s uid: %d type: %s path: %q",
+		a, sys.uid, TypeString(a.et), a.path)
 	return fmsg.WrapErrorSuffix(acl.UpdatePerm(a.path, sys.uid, a.perms...),
 		fmt.Sprintf("cannot apply ACL entry to %q:", a.path))
 }
 
 func (a *ACL) revert(sys *I, ec *Criteria) error {
 	if ec.hasType(a) {
-		verbose.Println("stripping ACL", a, "uid:", sys.uid, "type:", TypeString(a.et), "path:", a.path)
+		fmsg.VPrintf("stripping ACL %s uid: %d type: %s path: %q",
+			a, sys.uid, TypeString(a.et), a.path)
 		return fmsg.WrapErrorSuffix(acl.UpdatePerm(a.path, sys.uid),
 			fmt.Sprintf("cannot strip ACL entry from %q:", a.path))
 	} else {
-		verbose.Println("skipping ACL", a, "uid:", sys.uid, "tag:", TypeString(a.et), "path:", a.path)
+		fmsg.VPrintln("skipping ACL", a, "uid:", sys.uid, "tag:", TypeString(a.et), "path:", a.path)
 		return nil
 	}
 }

internal/system/dbus.go

@@ -2,12 +2,10 @@ package system
 
 import (
 	"errors"
-	"fmt"
 	"os"
 
 	"git.ophivana.moe/security/fortify/dbus"
 	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 var (
@@ -42,12 +40,12 @@ func (sys *I) ProxyDBus(session, system *dbus.Config, sessionPath, systemPath st
 	d.proxy = dbus.New(sessionBus, systemBus)
 
 	defer func() {
-		if verbose.Get() && d.proxy.Sealed() {
+		if fmsg.Verbose() && d.proxy.Sealed() {
-			verbose.Println("sealed session proxy", session.Args(sessionBus))
+			fmsg.VPrintln("sealed session proxy", session.Args(sessionBus))
 			if system != nil {
-				verbose.Println("sealed system proxy", system.Args(systemBus))
+				fmsg.VPrintln("sealed system proxy", system.Args(systemBus))
 			}
-			verbose.Println("message bus proxy final args:", d.proxy)
+			fmsg.VPrintln("message bus proxy final args:", d.proxy)
 		}
 	}()
 
@@ -73,9 +71,9 @@ func (d *DBus) Type() Enablement {
 }
 
 func (d *DBus) apply(_ *I) error {
-	verbose.Printf("session bus proxy on %q for upstream %q\n", d.proxy.Session()[1], d.proxy.Session()[0])
+	fmsg.VPrintf("session bus proxy on %q for upstream %q", d.proxy.Session()[1], d.proxy.Session()[0])
 	if d.system {
-		verbose.Printf("system bus proxy on %q for upstream %q\n", d.proxy.System()[1], d.proxy.System()[0])
+		fmsg.VPrintf("system bus proxy on %q for upstream %q", d.proxy.System()[1], d.proxy.System()[0])
 	}
 
 	// ready channel passed to dbus package
@@ -86,27 +84,27 @@ func (d *DBus) apply(_ *I) error {
 		return fmsg.WrapErrorSuffix(err,
 			"cannot start message bus proxy:")
 	}
-	verbose.Println("starting message bus proxy:", d.proxy)
+	fmsg.VPrintln("starting message bus proxy:", d.proxy)
-	if verbose.Get() { // save the extra bwrap arg build when verbose logging is off
+	if fmsg.Verbose() { // save the extra bwrap arg build when verbose logging is off
-		verbose.Println("message bus proxy bwrap args:", d.proxy.Bwrap())
+		fmsg.VPrintln("message bus proxy bwrap args:", d.proxy.Bwrap())
 	}
 
 	// background wait for proxy instance and notify completion
 	go func() {
 		if err := d.proxy.Wait(); err != nil {
-			fmt.Println("fortify: message bus proxy exited with error:", err)
+			fmsg.Println("message bus proxy exited with error:", err)
 			go func() { ready <- err }()
 		} else {
-			verbose.Println("message bus proxy exit")
+			fmsg.VPrintln("message bus proxy exit")
 		}
 
 		// ensure socket removal so ephemeral directory is empty at revert
 		if err := os.Remove(d.proxy.Session()[1]); err != nil && !errors.Is(err, os.ErrNotExist) {
-			fmt.Println("fortify: cannot remove dangling session bus socket:", err)
+			fmsg.Println("cannot remove dangling session bus socket:", err)
 		}
 		if d.system {
 			if err := os.Remove(d.proxy.System()[1]); err != nil && !errors.Is(err, os.ErrNotExist) {
-				fmt.Println("fortify: cannot remove dangling system bus socket:", err)
+				fmsg.Println("cannot remove dangling system bus socket:", err)
 			}
 		}
 
@@ -120,14 +118,14 @@ func (d *DBus) apply(_ *I) error {
 		return fmsg.WrapErrorSuffix(err,
 			"message bus proxy fault after start:")
 	}
-	verbose.Println("message bus proxy ready")
+	fmsg.VPrintln("message bus proxy ready")
 
 	return nil
 }
 
 func (d *DBus) revert(_ *I, _ *Criteria) error {
 	// criteria ignored here since dbus is always process-scoped
-	verbose.Println("terminating message bus proxy")
+	fmsg.VPrintln("terminating message bus proxy")
 
 	if err := d.proxy.Close(); err != nil {
 		if errors.Is(err, os.ErrClosed) {

internal/system/mkdir.go

@@ -6,7 +6,6 @@ import (
 	"os"
 
 	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 // Ensure the existence and mode of a directory.
@@ -37,7 +36,7 @@ func (m *Mkdir) Type() Enablement {
 }
 
 func (m *Mkdir) apply(_ *I) error {
-	verbose.Println("ensuring directory", m)
+	fmsg.VPrintln("ensuring directory", m)
 
 	// create directory
 	err := os.Mkdir(m.path, m.perm)
@@ -58,11 +57,11 @@ func (m *Mkdir) revert(_ *I, ec *Criteria) error {
 	}
 
 	if ec.hasType(m) {
-		verbose.Println("destroying ephemeral directory", m)
+		fmsg.VPrintln("destroying ephemeral directory", m)
 		return fmsg.WrapErrorSuffix(os.Remove(m.path),
 			fmt.Sprintf("cannot remove ephemeral directory %q:", m.path))
 	} else {
-		verbose.Println("skipping ephemeral directory", m)
+		fmsg.VPrintln("skipping ephemeral directory", m)
 		return nil
 	}
 }

internal/system/op.go

@@ -2,8 +2,9 @@ package system
 
 import (
 	"errors"
-	"fmt"
 	"sync"
+
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 )
 
 const (
@@ -80,7 +81,7 @@ func (sys *I) Commit() error {
 		if sp != nil {
 			// rollback partial commit
 			if err := sp.Revert(&Criteria{nil}); err != nil {
-				fmt.Println("fortify: errors returned reverting partial commit:", err)
+				fmsg.Println("errors returned reverting partial commit:", err)
 			}
 		}
 	}()

internal/system/tmpfiles.go

@@ -9,7 +9,6 @@ import (
 
 	"git.ophivana.moe/security/fortify/acl"
 	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 // CopyFile registers an Op that copies path dst from src.
@@ -72,15 +71,15 @@ func (t *Tmpfile) Type() Enablement {
 func (t *Tmpfile) apply(_ *I) error {
 	switch t.method {
 	case tmpfileCopy:
-		verbose.Printf("publishing tmpfile %s\n", t)
+		fmsg.VPrintln("publishing tmpfile", t)
 		return fmsg.WrapErrorSuffix(copyFile(t.dst, t.src),
 			fmt.Sprintf("cannot copy tmpfile %q:", t.dst))
 	case tmpfileLink:
-		verbose.Printf("linking tmpfile %s\n", t)
+		fmsg.VPrintln("linking tmpfile", t)
 		return fmsg.WrapErrorSuffix(os.Link(t.src, t.dst),
 			fmt.Sprintf("cannot link tmpfile %q:", t.dst))
 	case tmpfileWrite:
-		verbose.Printf("writing %s\n", t)
+		fmsg.VPrintln("writing", t)
 		return fmsg.WrapErrorSuffix(os.WriteFile(t.dst, []byte(t.src), 0600),
 			fmt.Sprintf("cannot write tmpfile %q:", t.dst))
 	default:
@@ -90,11 +89,11 @@ func (t *Tmpfile) apply(_ *I) error {
 
 func (t *Tmpfile) revert(_ *I, ec *Criteria) error {
 	if ec.hasType(t) {
-		verbose.Printf("removing tmpfile %q\n", t.dst)
+		fmsg.VPrintf("removing tmpfile %q", t.dst)
 		return fmsg.WrapErrorSuffix(os.Remove(t.dst),
 			fmt.Sprintf("cannot remove tmpfile %q:", t.dst))
 	} else {
-		verbose.Printf("skipping tmpfile %q\n", t.dst)
+		fmsg.VPrintf("skipping tmpfile %q", t.dst)
 		return nil
 	}
 }

internal/system/xhost.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 
 	"git.ophivana.moe/security/fortify/internal/fmsg"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 	"git.ophivana.moe/security/fortify/xcb"
 )
 
@@ -23,18 +22,18 @@ func (x XHost) Type() Enablement {
 }
 
 func (x XHost) apply(_ *I) error {
-	verbose.Printf("inserting entry %s to X11\n", x)
+	fmsg.VPrintf("inserting entry %s to X11", x)
 	return fmsg.WrapErrorSuffix(xcb.ChangeHosts(xcb.HostModeInsert, xcb.FamilyServerInterpreted, "localuser\x00"+string(x)),
 		fmt.Sprintf("cannot insert entry %s to X11:", x))
 }
 
 func (x XHost) revert(_ *I, ec *Criteria) error {
 	if ec.hasType(x) {
-		verbose.Printf("deleting entry %s from X11\n", x)
+		fmsg.VPrintf("deleting entry %s from X11", x)
 		return fmsg.WrapErrorSuffix(xcb.ChangeHosts(xcb.HostModeDelete, xcb.FamilyServerInterpreted, "localuser\x00"+string(x)),
 			fmt.Sprintf("cannot delete entry %s from X11:", x))
 	} else {
-		verbose.Printf("skipping entry %s in X11\n", x)
+		fmsg.VPrintf("skipping entry %s in X11", x)
 		return nil
 	}
 }

internal/verbose/print.go

@@ -1,19 +0,0 @@
-package verbose
-
-import (
-	"fmt"
-)
-
-var Prefix = "fortify:"
-
-func Println(a ...any) {
-	if verbose.Load() {
-		fmt.Println(append([]any{Prefix}, a...)...)
-	}
-}
-
-func Printf(format string, a ...any) {
-	if verbose.Load() {
-		fmt.Printf(Prefix+" "+format, a...)
-	}
-}

internal/verbose/print_test.go

@@ -1,67 +0,0 @@
-package verbose_test
-
-import (
-	"os"
-	"os/exec"
-	"strconv"
-	"strings"
-	"testing"
-
-	"git.ophivana.moe/security/fortify/internal/verbose"
-)
-
-const (
-	testVerbose = "GO_TEST_VERBOSE"
-	wantStdout  = "fortify: println\nfortify: printf"
-)
-
-func TestPrinter(t *testing.T) {
-	switch os.Getenv(testVerbose) {
-	case "0":
-		verbose.Set(false)
-	case "1":
-		verbose.Set(true)
-	default:
-		return
-	}
-
-	verbose.Println("println")
-	verbose.Printf("%s", "printf")
-}
-
-func TestPrintf_Println(t *testing.T) {
-	testPrintfPrintln(t, false)
-	testPrintfPrintln(t, true)
-
-	// make -cover happy
-	stdout := os.Stdout
-	t.Cleanup(func() {
-		os.Stdout = stdout
-	})
-	os.Stdout = nil
-	verbose.Set(true)
-	verbose.Printf("")
-	verbose.Println()
-}
-
-func testPrintfPrintln(t *testing.T, v bool) {
-	t.Run("start verbose printer with verbose "+strconv.FormatBool(v), func(t *testing.T) {
-		stdout, stderr := new(strings.Builder), new(strings.Builder)
-		stdout.Grow(len(wantStdout))
-		cmd := exec.Command(os.Args[0], "-test.run=TestPrinter")
-		cmd.Stdout, cmd.Stderr = stdout, stderr
-		if v {
-			cmd.Env = append(cmd.Env, testVerbose+"=1")
-		} else {
-			cmd.Env = append(cmd.Env, testVerbose+"=0")
-		}
-		if err := cmd.Run(); err != nil {
-			panic("cannot run printer process: " + err.Error() + " stderr: " + stderr.String())
-		}
-
-		if got := stdout.String(); strings.Contains(got, wantStdout) != v {
-			t.Errorf("Print: got %v; want %t",
-				got, v)
-		}
-	})
-}

internal/verbose/state.go

@@ -1,13 +0,0 @@
-package verbose
-
-import "sync/atomic"
-
-var verbose = new(atomic.Bool)
-
-func Get() bool {
-	return verbose.Load()
-}
-
-func Set(v bool) {
-	verbose.Store(v)
-}

internal/verbose/state_test.go

@@ -1,20 +0,0 @@
-package verbose_test
-
-import (
-	"testing"
-
-	"git.ophivana.moe/security/fortify/internal/verbose"
-)
-
-func TestGetSet(t *testing.T) {
-	verbose.Set(false)
-	if verbose.Get() {
-		t.Errorf("Get() = true, want false")
-	}
-
-	verbose.Set(true)
-	if !verbose.Get() {
-		t.Errorf("Get() = false, want true")
-	}
-
-}

main.go

@@ -2,15 +2,14 @@ package main
 
 import (
 	"flag"
-	"fmt"
 	"os"
 	"syscall"
 
 	"git.ophivana.moe/security/fortify/internal"
 	"git.ophivana.moe/security/fortify/internal/app"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 	init0 "git.ophivana.moe/security/fortify/internal/init"
 	"git.ophivana.moe/security/fortify/internal/shim"
-	"git.ophivana.moe/security/fortify/internal/verbose"
 )
 
 var (
@@ -24,14 +23,14 @@ func init() {
 func main() {
 	// linux/sched/coredump.h
 	if _, _, errno := syscall.RawSyscall(syscall.SYS_PRCTL, syscall.PR_SET_DUMPABLE, 0, 0); errno != 0 {
-		fmt.Printf("fortify: cannot set SUID_DUMP_DISABLE: %s", errno.Error())
+		fmsg.Printf("fortify: cannot set SUID_DUMP_DISABLE: %s", errno.Error())
 	}
 
 	flag.Parse()
-	verbose.Set(flagVerbose)
+	fmsg.SetVerbose(flagVerbose)
 
 	if internal.SdBootedV {
-		verbose.Println("system booted with systemd as init system")
+		fmsg.VPrintln("system booted with systemd as init system")
 	}
 
 	// shim/init early exit
@@ -40,7 +39,7 @@ func main() {
 
 	// root check
 	if os.Getuid() == 0 {
-		fmt.Println("fortify: this program must not run as root")
+		fmsg.Println("this program must not run as root")
 		os.Exit(1)
 	}
 
@@ -56,7 +55,7 @@ func main() {
 	r := 1
 	a, err := app.New()
 	if err != nil {
-		fatalf("cannot create app: %s\n", err)
+		fmsg.Fatalf("cannot create app: %s\n", err)
 	} else if err = a.Seal(loadConfig()); err != nil {
 		logBaseError(err, "fortify: cannot seal app:")
 	} else if err = a.Start(); err != nil {
@@ -68,7 +67,7 @@ func main() {
 		logWaitError(err)
 	}
 	if err = a.WaitErr(); err != nil {
-		fmt.Println("fortify: inner wait failed:", err)
+		fmsg.Println("inner wait failed:", err)
 	}
 	os.Exit(r)
 }

state.go

@@ -7,6 +7,7 @@ import (
 	"text/tabwriter"
 
 	"git.ophivana.moe/security/fortify/internal"
+	"git.ophivana.moe/security/fortify/internal/fmsg"
 	"git.ophivana.moe/security/fortify/internal/state"
 )
 
@@ -25,7 +26,7 @@ func tryState() {
 		state.MustPrintLauncherStateSimpleGlobal(&w, internal.GetSC().RunDirPath)
 		if w != nil {
 			if err := w.Flush(); err != nil {
-				fmt.Println("warn: error formatting output:", err)
+				fmsg.Println("cannot format output:", err)
 			}
 		} else {
 			fmt.Println("No information available")