Create socket dir on startup

dist/freebsd/etc/rc.d/zrepl

@@ -49,7 +49,7 @@ load_rc_config "$name"
 : "${zrepl_gracefully:=NO}"
 
 : "${zrepl_control_group:=$zrepl_group}"
-: "${zrepl_control_mode:=0700}"
+: "${zrepl_control_mode:=0750}"
 
 pidfile="/var/run/zrepl.pid"
 command="/usr/sbin/daemon"
@@ -71,10 +71,8 @@ zrepl_checkconfig() {
 }
 
 zrepl_precmd() {
-    if [ ! -d "/var/run/zrepl" ]; then
-        install -d -g "$zrepl_control_group" -o "$zrepl_user" \
-                -m "$zrepl_control_mode"   "/var/run/zrepl"
-    fi
+    install -d -g "$zrepl_control_group" -o "$zrepl_user" \
+            -m "$zrepl_control_mode" "/var/run/zrepl"
     zrepl_checkconfig
 }
 

internal/daemon/http.go

@@ -7,6 +7,7 @@ import (
 	"net"
 	"net/http"
 	"os"
+	"path/filepath"
 	"sync"
 )
 
@@ -32,15 +33,24 @@ func (self *server) Clone() *server {
 }
 
 func (self *server) WithUnix(path string, mode uint32) error {
+	if err := unlinkStaleUnix(path); err != nil {
+		return err
+	}
+
 	self.Addr = path
 	laddr, err := net.ResolveUnixAddr("unix", path)
 	if err != nil {
 		return fmt.Errorf("resolve unix address %q: %w", path, err)
 	}
 
-	if self.listener, err = net.ListenUnix("unix", laddr); err != nil {
+	l, err := net.ListenUnix("unix", laddr)
+	if err != nil {
 		return fmt.Errorf("listen unix on %q: %w", path, err)
-	} else if mode == 0 {
+	}
+
+	l.SetUnlinkOnClose(true)
+	self.listener = l
+	if mode == 0 {
 		return nil
 	}
 
@@ -50,6 +60,33 @@ func (self *server) WithUnix(path string, mode uint32) error {
 	return nil
 }
 
+func unlinkStaleUnix(path string) error {
+	sockdir := filepath.Dir(path)
+	stat, err := os.Stat(sockdir)
+	switch {
+	case err != nil && os.IsNotExist(err):
+		if err := os.MkdirAll(sockdir, 0o755); err != nil {
+			return fmt.Errorf("cannot mkdir %q: %w", sockdir, err)
+		}
+		return nil
+	case err != nil:
+		return fmt.Errorf("cannot stat(2) %q: %w", sockdir, err)
+	case !stat.IsDir():
+		return fmt.Errorf("not a directory: %q", sockdir)
+	}
+
+	_, err = os.Stat(path)
+	switch {
+	case err == nil:
+		if err := os.Remove(path); err != nil {
+			return fmt.Errorf("cannot remove stale socket %q: %w", path, err)
+		}
+	case !os.IsNotExist(err):
+		return fmt.Errorf("cannot stat(2) %q: %w", path, err)
+	}
+	return nil
+}
+
 //nolint:wrapcheck // not needed
 func (self *server) Serve() error {
 	self.initTLSConfig()