c4a6bed feat(cli): add -display and NEFERBAR_DISPLAY to pick the Wayland socket, and clear connect errors · neferbar

M README.md +3 -1


@@ -15,7 +15,9 @@ go build -o neferbar ./cmd/neferbar
15	15		./neferbar -config examples/config.toml
16	16		```
17	17
18		-	Flags: `-config <file>`, `-pprof <loopback addr>`, `-memstats <interval>`.
	18	+	Flags: `-config <file>`, `-display <socket>`, `-pprof <loopback addr>`, `-memstats <interval>`.
	19	+
	20	+	The Wayland socket comes from `-display`, then `$NEFERBAR_DISPLAY`, then `$WAYLAND_DISPLAY`, then `wayland-0`. A relative name lives in `$XDG_RUNTIME_DIR`; an absolute path is used as is.
19	21
20	22		## Configuration
21	23


@@ -15,7 +15,9 @@ go build -o neferbar ./cmd/neferbar
15		./neferbar -config examples/config.toml	15		./neferbar -config examples/config.toml
16		```	16		```
17			17
18	-	Flags: `-config <file>`, `-pprof <loopback addr>`, `-memstats <interval>`.	18	+	Flags: `-config <file>`, `-display <socket>`, `-pprof <loopback addr>`, `-memstats <interval>`.
			19	+
			20	+	The Wayland socket comes from `-display`, then `$NEFERBAR_DISPLAY`, then `$WAYLAND_DISPLAY`, then `wayland-0`. A relative name lives in `$XDG_RUNTIME_DIR`; an absolute path is used as is.
19			21
20		## Configuration	22		## Configuration
21			23

M cmd/neferbar/main.go +6 -8


@@ -21,6 +21,7 @@ import (
21	21
22	22		func main() {
23	23		cfgPath := flag.String("config", "", "config file (default: $XDG_CONFIG_HOME/neferbar/config.toml)")
	24	+	display := flag.String("display", os.Getenv("NEFERBAR_DISPLAY"), "Wayland socket name or absolute path (default: $NEFERBAR_DISPLAY, then $WAYLAND_DISPLAY)")
24	25		pprofAddr := flag.String("pprof", "", "serve pprof on this loopback address, e.g. localhost:6060")
25	26		memStats := flag.Duration("memstats", 0, "log allocation counters at this interval (0: off)")
26	27		flag.Parse()

@@ -28,13 +29,13 @@ func main() {
28	29		log := slog.New(slog.NewTextHandler(os.Stderr, nil))
29	30		ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
30	31		defer stop()
31		-	if err := run(ctx, log, cfgPath, pprofAddr, *memStats); err != nil {
32		-	log.Error("neferbar", "err", err)
	32	+	if err := run(ctx, log, cfgPath, display, pprofAddr, memStats); err != nil {
	33	+	fmt.Fprintf(os.Stderr, "neferbar: %v\n", err)
33	34		os.Exit(1)
34	35		}
35	36		}
36	37
37		-	func run(ctx context.Context, log *slog.Logger, cfgPath, pprofAddr string, memStats time.Duration) error {
	38	+	func run(ctx context.Context, log *slog.Logger, cfgPath, display, pprofAddr string, memStats time.Duration) error {
38	39		explicit := cfgPath != ""
39	40		if !explicit {
40	41		cfgPath = config.DefaultPath()

@@ -48,17 +49,14 @@ func run(ctx context.Context, log *slog.Logger, cfgPath, pprofAddr string, memSt
48	49		return err
49	50		}
50	51		}
51		-	b, err := bar.New(cfg, log)
	52	+	b, err := bar.New(cfg, log, display)
52	53		if err != nil {
53	54		return err
54	55		}
55	56		if memStats > 0 {
56	57		go logMemStats(ctx, log, memStats)
57	58		}
58		-	err = b.Run(ctx)
59		-	log.Info("stats", "presented", b.Stats.Presented, "rebuilds", b.Stats.Rebuilds,
60		-	"recreated", b.Stats.Recreated, "no_slot", b.Stats.NoSlot, "dirty", b.Stats.Dirty, "module_wakes", b.Stats.ModuleWake)
61		-	return err
	59	+	return b.Run(ctx)
62	60		}
63	61
64	62		// servePprof serves the pprof handlers on a loopback address only.

 func main() {
 	cfgPath := flag.String("config", "", "config file (default: $XDG_CONFIG_HOME/neferbar/config.toml)")
+	display := flag.String("display", os.Getenv("NEFERBAR_DISPLAY"), "Wayland socket name or absolute path (default: $NEFERBAR_DISPLAY, then $WAYLAND_DISPLAY)")
 	pprofAddr := flag.String("pprof", "", "serve pprof on this loopback address, e.g. localhost:6060")
 	memStats := flag.Duration("memstats", 0, "log allocation counters at this interval (0: off)")
 	flag.Parse()
 	log := slog.New(slog.NewTextHandler(os.Stderr, nil))
 	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
 	defer stop()
-	if err := run(ctx, log, *cfgPath, *pprofAddr, *memStats); err != nil {
+	if err := run(ctx, log, *cfgPath, *display, *pprofAddr, *memStats); err != nil {
-		log.Error("neferbar", "err", err)
+		fmt.Fprintf(os.Stderr, "neferbar: %v\n", err)
 		os.Exit(1)
 	}
 }
-func run(ctx context.Context, log *slog.Logger, cfgPath, pprofAddr string, memStats time.Duration) error {
+func run(ctx context.Context, log *slog.Logger, cfgPath, display, pprofAddr string, memStats time.Duration) error {
 	explicit := cfgPath != ""
 	if !explicit {
 		cfgPath = config.DefaultPath()
 			return err
 		}
 	}
-	b, err := bar.New(cfg, log)
+	b, err := bar.New(cfg, log, display)
 	if err != nil {
 		return err
 	}
 	if memStats > 0 {
 		go logMemStats(ctx, log, memStats)
 	}
-	err = b.Run(ctx)
+	return b.Run(ctx)
-	log.Info("stats", "presented", b.Stats.Presented, "rebuilds", b.Stats.Rebuilds,
-		"recreated", b.Stats.Recreated, "no_slot", b.Stats.NoSlot, "dirty", b.Stats.Dirty, "module_wakes", b.Stats.ModuleWake)
-	return err
 }
 // servePprof serves the pprof handlers on a loopback address only.

M internal/bar/bar.go +44 -8


@@ -13,7 +13,9 @@ import (
13	13		"fmt"
14	14		"log/slog"
15	15		"math"
	16	+	"os"
16	17		"path/filepath"
	18	+	"syscall"
17	19
18	20		"github.com/bnema/neferclient"
19	21

@@ -40,9 +42,10 @@ type Stats struct {
40	42
41	43		// Bar is the running application.
42	44		type Bar struct {
43		-	cfg config.Config
44		-	log *slog.Logger
45		-	fg, bg [3]uint8
	45	+	cfg config.Config
	46	+	log *slog.Logger
	47	+	display string
	48	+	fg, bg [3]uint8
46	49
47	50		conn *neferclient.Conn
48	51		surf *neferclient.Surface

@@ -76,8 +79,9 @@ type Bar struct {
76	79		}
77	80
78	81		// New builds a bar from a validated config.
79		-	func New(cfg config.Config, log slog.Logger) (Bar, error) {
80		-	b := &Bar{cfg: cfg, log: log, modCh: make(chan struct{}, 1)}
	82	+	// display names the Wayland socket; empty uses $WAYLAND_DISPLAY.
	83	+	func New(cfg config.Config, log slog.Logger, display string) (Bar, error) {
	84	+	b := &Bar{cfg: cfg, log: log, display: display, modCh: make(chan struct{}, 1)}
81	85		var err error
82	86		if b.fg, err = config.ParseColor(cfg.Bar.Foreground); err != nil {
83	87		return nil, err

@@ -104,11 +108,15 @@ func New(cfg config.Config, log slog.Logger) (Bar, error) {
104	108		// Run connects to the compositor and serves until ctx ends or the surface is
105	109		// closed. It returns the first fatal error.
106	110		func (b *Bar) Run(ctx context.Context) (err error) {
107		-	b.conn, err = neferclient.Connect(ctx, "")
	111	+	b.conn, err = neferclient.Connect(ctx, b.display)
108	112		if err != nil {
109		-	return fmt.Errorf("connect: %w", err)
	113	+	return connectError(b.display, err)
110	114		}
111		-	defer func() { err = errors.Join(err, b.shutdown()) }()
	115	+	defer func() {
	116	+	err = errors.Join(err, b.shutdown())
	117	+	b.log.Info("stats", "presented", b.Stats.Presented, "rebuilds", b.Stats.Rebuilds,
	118	+	"recreated", b.Stats.Recreated, "no_slot", b.Stats.NoSlot, "dirty", b.Stats.Dirty, "module_wakes", b.Stats.ModuleWake)
	119	+	}()
112	120		if err = b.createSurface(estimateHeight(b.cfg.Bar.Size * b.cfg.Bar.Scale)); err != nil {
113	121		return err
114	122		}

@@ -138,6 +146,34 @@ func (b *Bar) Run(ctx context.Context) (err error) {
138	146		return nil
139	147		}
140	148
	149	+	// socketPath mirrors how neferclient resolves the socket, for error messages.
	150	+	func socketPath(display string) string {
	151	+	if display == "" {
	152	+	display = os.Getenv("WAYLAND_DISPLAY")
	153	+	}
	154	+	if display == "" {
	155	+	display = "wayland-0"
	156	+	}
	157	+	if filepath.IsAbs(display) {
	158	+	return display
	159	+	}
	160	+	return filepath.Join(os.Getenv("XDG_RUNTIME_DIR"), display)
	161	+	}
	162	+
	163	+	// connectError turns a failed dial into one actionable sentence.
	164	+	func connectError(display string, err error) error {
	165	+	path := socketPath(display)
	166	+	switch {
	167	+	case errors.Is(err, os.ErrNotExist):
	168	+	return fmt.Errorf("no Wayland socket at %s: is the compositor running? Set WAYLAND_DISPLAY, NEFERBAR_DISPLAY or -display", path)
	169	+	case errors.Is(err, syscall.ECONNREFUSED):
	170	+	return fmt.Errorf("the Wayland socket %s exists but refuses connections: stale socket or compositor not ready", path)
	171	+	case errors.Is(err, os.ErrPermission):
	172	+	return fmt.Errorf("not allowed to open the Wayland socket %s", path)
	173	+	}
	174	+	return err
	175	+	}
	176	+
141	177		// estimateHeight is the first request, before the real cell height is known.
142	178		func estimateHeight(px float64) int32 { return int32(math.Ceil(px * 1.5)) }
143	179

 	"fmt"
 	"log/slog"
 	"math"
+	"os"
 	"path/filepath"
+	"syscall"
 	"github.com/bnema/neferclient"
 // Bar is the running application.
 type Bar struct {
-	cfg    config.Config
+	cfg     config.Config
-	log    *slog.Logger
+	log     *slog.Logger
-	fg, bg [3]uint8
+	display string
+	fg, bg  [3]uint8
 	conn *neferclient.Conn
 	surf *neferclient.Surface
 }
 // New builds a bar from a validated config.
-func New(cfg config.Config, log *slog.Logger) (*Bar, error) {
+// display names the Wayland socket; empty uses $WAYLAND_DISPLAY.
-	b := &Bar{cfg: cfg, log: log, modCh: make(chan struct{}, 1)}
+func New(cfg config.Config, log *slog.Logger, display string) (*Bar, error) {
+	b := &Bar{cfg: cfg, log: log, display: display, modCh: make(chan struct{}, 1)}
 	var err error
 	if b.fg, err = config.ParseColor(cfg.Bar.Foreground); err != nil {
 		return nil, err
 // Run connects to the compositor and serves until ctx ends or the surface is
 // closed. It returns the first fatal error.
 func (b *Bar) Run(ctx context.Context) (err error) {
-	b.conn, err = neferclient.Connect(ctx, "")
+	b.conn, err = neferclient.Connect(ctx, b.display)
 	if err != nil {
-		return fmt.Errorf("connect: %w", err)
+		return connectError(b.display, err)
 	}
-	defer func() { err = errors.Join(err, b.shutdown()) }()
+	defer func() {
+		err = errors.Join(err, b.shutdown())
+		b.log.Info("stats", "presented", b.Stats.Presented, "rebuilds", b.Stats.Rebuilds,
+			"recreated", b.Stats.Recreated, "no_slot", b.Stats.NoSlot, "dirty", b.Stats.Dirty, "module_wakes", b.Stats.ModuleWake)
+	}()
 	if err = b.createSurface(estimateHeight(b.cfg.Bar.Size * b.cfg.Bar.Scale)); err != nil {
 		return err
 	}
 	return nil
 }
+// socketPath mirrors how neferclient resolves the socket, for error messages.
+func socketPath(display string) string {
+	if display == "" {
+		display = os.Getenv("WAYLAND_DISPLAY")
+	}
+	if display == "" {
+		display = "wayland-0"
+	}
+	if filepath.IsAbs(display) {
+		return display
+	}
+	return filepath.Join(os.Getenv("XDG_RUNTIME_DIR"), display)
+}
+// connectError turns a failed dial into one actionable sentence.
+func connectError(display string, err error) error {
+	path := socketPath(display)
+	switch {
+	case errors.Is(err, os.ErrNotExist):
+		return fmt.Errorf("no Wayland socket at %s: is the compositor running? Set WAYLAND_DISPLAY, NEFERBAR_DISPLAY or -display", path)
+	case errors.Is(err, syscall.ECONNREFUSED):
+		return fmt.Errorf("the Wayland socket %s exists but refuses connections: stale socket or compositor not ready", path)
+	case errors.Is(err, os.ErrPermission):
+		return fmt.Errorf("not allowed to open the Wayland socket %s", path)
+	}
+	return err
+}
 // estimateHeight is the first request, before the real cell height is known.
 func estimateHeight(px float64) int32 { return int32(math.Ceil(px * 1.5)) }

M scripts/headless.sh +2 -2


@@ -2,7 +2,7 @@
2	2		# Run neferbar against a nested headless NeferWL with a clean environment.
3	3		# usage: scripts/headless.sh <config> <seconds> [neferbar args...]
4	4		# env: SIZE=WxH (output size), SCALE=1.5 (output scale), OUT=dir (screenshots),
5		-	# NEFERBAR=binary, LOGLINES=n (compositor log lines to show).
	5	+	# DISPLAY_VAR=NEFERBAR_DISPLAY (pass the socket that way), NEFERBAR=binary, LOGLINES=n (compositor log lines to show).
6	6		set -eu
7	7		cfg=$1; secs=$2; shift 2
8	8		out=${OUT:-/tmp/neferbar-shots}

@@ -24,6 +24,6 @@ for _ in $(seq 100); do
24	24		done
25	25		[ -n "${sock:-}" ] \|\| { echo "no compositor socket"; cat "$root/neferwl.log"; exit 1; }
26	26		set +e
27		-	timeout "$secs" "${clean[@]}" WAYLAND_DISPLAY="$sock" "${NEFERBAR:-/tmp/neferbar}" -config "$cfg" "$@"
	27	+	timeout "$secs" "${clean[@]}" "${DISPLAY_VAR:-WAYLAND_DISPLAY}=$sock" "${NEFERBAR:-/tmp/neferbar}" -config "$cfg" "$@"
28	28		echo "neferbar exit: $?"
29	29		echo "--- compositor log"; grep -v "not a conformant" "$root/neferwl.log" \| tail -"${LOGLINES:-8}"; cp "$root/neferwl.log" /tmp/neferwl-last.log


@@ -2,7 +2,7 @@
2		# Run neferbar against a nested headless NeferWL with a clean environment.	2		# Run neferbar against a nested headless NeferWL with a clean environment.
3		# usage: scripts/headless.sh <config> <seconds> [neferbar args...]	3		# usage: scripts/headless.sh <config> <seconds> [neferbar args...]
4		# env: SIZE=WxH (output size), SCALE=1.5 (output scale), OUT=dir (screenshots),	4		# env: SIZE=WxH (output size), SCALE=1.5 (output scale), OUT=dir (screenshots),
5	-	# NEFERBAR=binary, LOGLINES=n (compositor log lines to show).	5	+	# DISPLAY_VAR=NEFERBAR_DISPLAY (pass the socket that way), NEFERBAR=binary, LOGLINES=n (compositor log lines to show).
6		set -eu	6		set -eu
7		cfg=$1; secs=$2; shift 2	7		cfg=$1; secs=$2; shift 2
8		out=${OUT:-/tmp/neferbar-shots}	8		out=${OUT:-/tmp/neferbar-shots}

@@ -24,6 +24,6 @@ for _ in $(seq 100); do
24		done	24		done
25		[ -n "${sock:-}" ] \|\| { echo "no compositor socket"; cat "$root/neferwl.log"; exit 1; }	25		[ -n "${sock:-}" ] \|\| { echo "no compositor socket"; cat "$root/neferwl.log"; exit 1; }
26		set +e	26		set +e
27	-	timeout "$secs" "${clean[@]}" WAYLAND_DISPLAY="$sock" "${NEFERBAR:-/tmp/neferbar}" -config "$cfg" "$@"	27	+	timeout "$secs" "${clean[@]}" "${DISPLAY_VAR:-WAYLAND_DISPLAY}=$sock" "${NEFERBAR:-/tmp/neferbar}" -config "$cfg" "$@"
28		echo "neferbar exit: $?"	28		echo "neferbar exit: $?"
29		echo "--- compositor log"; grep -v "not a conformant" "$root/neferwl.log" \| tail -"${LOGLINES:-8}"; cp "$root/neferwl.log" /tmp/neferwl-last.log	29		echo "--- compositor log"; grep -v "not a conformant" "$root/neferwl.log" \| tail -"${LOGLINES:-8}"; cp "$root/neferwl.log" /tmp/neferwl-last.log