Merge pull request #26029 from Luap99/machine-tz

pkg/machine: more timezone fixes

pkg/machine/e2e/init_test.go

@@ -279,6 +279,12 @@ var _ = Describe("podman machine init", func() {
 		Expect(err).ToNot(HaveOccurred())
 		Expect(timezoneSession).To(Exit(0))
 		Expect(timezoneSession.outputToString()).To(ContainSubstring("HST"))
+
+		sshTimezone = sshMachine{}
+		timezoneSession, err = mb.setName(name).setCmd(sshTimezone.withSSHCommand([]string{"timedatectl show --property Timezone"})).run()
+		Expect(err).ToNot(HaveOccurred())
+		Expect(timezoneSession).To(Exit(0))
+		Expect(timezoneSession.outputToString()).To(ContainSubstring("Pacific/Honolulu"))
 	})
 
 	It("machine init with swap", func() {

pkg/machine/ignition/ignition.go

@@ -143,36 +143,43 @@ func (ign *DynamicIgnition) GenerateIgnitionConfig() error {
 
 	// Add or set the time zone for the machine
 	if len(ign.TimeZone) > 0 {
-		var (
-			err error
-			tz  string
-		)
+		var err error
+		tz := ign.TimeZone
 		// local means the same as the host
 		// look up where it is pointing to on the host
 		if ign.TimeZone == "local" {
-			tz, err = getLocalTimeZone()
-			if err != nil {
-				return fmt.Errorf("error getting local timezone: %q", err)
+			if env, ok := os.LookupEnv("TZ"); ok {
+				tz = env
+			} else {
+				tz, err = getLocalTimeZone()
+				if err != nil {
+					return fmt.Errorf("error getting local timezone: %q", err)
+				}
 			}
+		}
+		// getLocalTimeZone() can return empty string, do not add broken symlink in that case
+		// coreos will default to UTC
+		if tz == "" {
+			logrus.Info("Unable to determine local timezone, machine will default to UTC")
 		} else {
-			tz = ign.TimeZone
+			tzLink := Link{
+				Node: Node{
+					Group:     GetNodeGrp("root"),
+					Path:      "/etc/localtime",
+					Overwrite: BoolToPtr(false),
+					User:      GetNodeUsr("root"),
+				},
+				LinkEmbedded1: LinkEmbedded1{
+					Hard: BoolToPtr(false),
+					// We always want this value in unix form (../usr/share/zoneinfo) because this is being
+					// set in the machine OS (always Linux) and systemd needs the relative symlink.  However,
+					// filepath.join on windows will use a "\\" separator so use path.Join() which always
+					// uses the slash.
+					Target: path.Join("../usr/share/zoneinfo", tz),
+				},
+			}
+			ignStorage.Links = append(ignStorage.Links, tzLink)
 		}
-		tzLink := Link{
-			Node: Node{
-				Group:     GetNodeGrp("root"),
-				Path:      "/etc/localtime",
-				Overwrite: BoolToPtr(false),
-				User:      GetNodeUsr("root"),
-			},
-			LinkEmbedded1: LinkEmbedded1{
-				Hard: BoolToPtr(false),
-				// We always want this value in unix form (/path/to/something) because this is being
-				// set in the machine OS (always Linux).  However, filepath.join on windows will use a "\\"
-				// separator; therefore we use ToSlash to convert the path to unix style
-				Target: filepath.ToSlash(filepath.Join("/usr/share/zoneinfo", tz)),
-			},
-		}
-		ignStorage.Links = append(ignStorage.Links, tzLink)
 	}
 
 	// This service gets environment variables that are provided

pkg/machine/ignition/ignition_linux.go

@@ -1,29 +1,29 @@
 package ignition
 
 import (
+	"errors"
 	"os"
-	"os/exec"
+	"path/filepath"
 	"strings"
-
-	"github.com/sirupsen/logrus"
 )
 
 func getLocalTimeZone() (string, error) {
-	trimTzFunc := func(s string) string {
-		return strings.TrimPrefix(strings.TrimSuffix(s, "\n"), "Timezone=")
+	path, err := filepath.EvalSymlinks("/etc/localtime")
+	if err != nil {
+		// of the path does not exist, ignore it as the code default to UTC then
+		if errors.Is(err, os.ErrNotExist) {
+			return "", nil
+		}
+		return "", err
 	}
 
-	// perform a variety of ways to see if we can determine the tz
-	output, err := exec.Command("timedatectl", "show", "--property=Timezone").Output()
-	if err == nil {
-		return trimTzFunc(string(output)), nil
+	// Allow using TZDIR per:
+	// https://sourceware.org/git/?p=glibc.git;a=blob;f=time/tzfile.c;h=8a923d0cccc927a106dc3e3c641be310893bab4e;hb=HEAD#l149
+	zoneinfo := os.Getenv("TZDIR")
+	if zoneinfo == "" {
+		// default zoneinfo location
+		zoneinfo = "/usr/share/zoneinfo"
 	}
-	logrus.Debugf("Timedatectl show --property=Timezone failed: %s", err)
-	output, err = os.ReadFile("/etc/timezone")
-	if err == nil {
-		return trimTzFunc(string(output)), nil
-	}
-	logrus.Debugf("unable to read /etc/timezone, falling back to empty timezone: %s", err)
-	// if we cannot determine the tz, return empty string
-	return "", nil
+	// Trim of the TZDIR part to extract the actual timezone name
+	return strings.TrimPrefix(path, filepath.Clean(zoneinfo)+"/"), nil
 }