cmd/dockerd: windows: move setting PIDFile location to setPlatformOptions

Unlike Linux, which uses fixed locations as default, the Windows daemon uses
paths relative to the data-root as defaults for storing both the PIDFile, and
the daemon configuration file (daemon.json).

The data-root is configurable both through command-line options (`--data-root`),
and through the daemon configuration file (daemon.json). This patch moves Windows-
specific config handling to config-related code.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cmd/dockerd/daemon_windows.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"path/filepath"
 	"time"
 
 	"github.com/containerd/log"
@@ -23,8 +24,14 @@ func getDefaultDaemonConfigFile() string {
 }
 
 // setPlatformOptions applies platform-specific CLI configuration options.
-// There is none on windows, so this is a no-op.
 func setPlatformOptions(conf *config.Config) error {
+	if conf.Pidfile == "" {
+		// On Windows, the pid-file location is relative to the daemon's data-root,
+		// which is configurable, so we cannot use a fixed default location.
+		// Instead, we set the location here, after we parsed command-line flags
+		// and loaded the configuration file (if any).
+		conf.Pidfile = filepath.Join(conf.Root, "docker.pid")
+	}
 	return nil
 }
 

cmd/dockerd/docker_windows.go

@@ -4,17 +4,12 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"path/filepath"
 
 	"github.com/Microsoft/go-winio/pkg/etwlogrus"
 	"github.com/containerd/log"
 )
 
 func runDaemon(opts *daemonOptions) error {
-	// Windows specific settings as these are not defaulted.
-	if opts.daemonConfig.Pidfile == "" {
-		opts.daemonConfig.Pidfile = filepath.Join(opts.daemonConfig.Root, "docker.pid")
-	}
 	cli, err := NewDaemonCli(opts)
 	if err != nil {
 		return err