Add --tz flag to create, run

--tz flag sets timezone inside container
Can be set to IANA timezone as well as `local` to match host machine

Signed-off-by: Ashley Cui <acui@redhat.com>

5 files changed, 95 insertions, 0 deletions

diff --git a/libpod/container.go b/libpod/container.go
index 20688e3ee..8ea25d6a0 100644
--- a/libpod/container.go
+++ b/libpod/container.go
@@ -424,6 +424,10 @@ type ContainerConfig struct {
 	// to 0, 1, 2) that will be passed to the executed process. The total FDs
 	// passed will be 3 + PreserveFDs.
 	PreserveFDs uint `json:"preserveFds,omitempty"`
+
+	// Timezone is the timezone inside the container.
+	// Local means it has the same timezone as the host machine
+	Timezone string `json:"timezone,omitempty"`
 }
 
 // ContainerNamedVolume is a named volume that will be mounted into the
@@ -1248,3 +1252,8 @@ func (c *Container) AutoRemove() bool {
 	}
 	return c.Spec().Annotations[define.InspectAnnotationAutoremove] == define.InspectResponseTrue
 }
+
+func (c *Container) Timezone() string {
+	return c.config.Timezone
+
+}
diff --git a/libpod/container_inspect.go b/libpod/container_inspect.go
index c6d9e1a65..9fbdf2c8b 100644
--- a/libpod/container_inspect.go
+++ b/libpod/container_inspect.go
@@ -322,6 +322,8 @@ func (c *Container) generateInspectContainerConfig(spec *spec.Spec) *define.Insp
 
 	ctrConfig.CreateCommand = c.config.CreateCommand
 
+	ctrConfig.Timezone = c.config.Timezone
+
 	return ctrConfig
 }
 
diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go
index 2c78f6bd2..d61268eab 100644
--- a/libpod/container_internal_linux.go
+++ b/libpod/container_internal_linux.go
@@ -1241,6 +1241,31 @@ func (c *Container) makeBindMounts() error {
 		c.state.BindMounts["/etc/hostname"] = hostnamePath
 	}
 
+	// Make /etc/localtime
+	if c.Timezone() != "" {
+		if _, ok := c.state.BindMounts["/etc/localtime"]; !ok {
+			var zonePath string
+			if c.Timezone() == "local" {
+				zonePath, err = filepath.EvalSymlinks("/etc/localtime")
+				if err != nil {
+					return errors.Wrapf(err, "error finding local timezone for container %s", c.ID())
+				}
+			} else {
+				zone := filepath.Join("/usr/share/zoneinfo", c.Timezone())
+				zonePath, err = filepath.EvalSymlinks(zone)
+				if err != nil {
+					return errors.Wrapf(err, "error setting timezone for container %s", c.ID())
+				}
+			}
+			localtimePath, err := c.copyTimezoneFile(zonePath)
+			if err != nil {
+				return errors.Wrapf(err, "error setting timezone for container %s", c.ID())
+			}
+			c.state.BindMounts["/etc/localtime"] = localtimePath
+
+		}
+	}
+
 	// Make .containerenv
 	// Empty file, so no need to recreate if it exists
 	if _, ok := c.state.BindMounts["/run/.containerenv"]; !ok {
@@ -1533,3 +1558,35 @@ func (c *Container) getOCICgroupPath() (string, error) {
 		return "", errors.Wrapf(define.ErrInvalidArg, "invalid cgroup manager %s requested", c.runtime.config.Engine.CgroupManager)
 	}
 }
+
+func (c *Container) copyTimezoneFile(zonePath string) (string, error) {
+	var localtimeCopy string = filepath.Join(c.state.RunDir, "localtime")
+	file, err := os.Stat(zonePath)
+	if err != nil {
+		return "", err
+	}
+	if file.IsDir() {
+		return "", errors.New("Invalid timezone: is a directory")
+	}
+	src, err := os.Open(zonePath)
+	if err != nil {
+		return "", err
+	}
+	defer src.Close()
+	dest, err := os.Create(localtimeCopy)
+	if err != nil {
+		return "", err
+	}
+	defer dest.Close()
+	_, err = io.Copy(dest, src)
+	if err != nil {
+		return "", err
+	}
+	if err := label.Relabel(localtimeCopy, c.config.MountLabel, false); err != nil {
+		return "", err
+	}
+	if err := dest.Chown(c.RootUID(), c.RootGID()); err != nil {
+		return "", err
+	}
+	return localtimeCopy, err
+}
diff --git a/libpod/define/container_inspect.go b/libpod/define/container_inspect.go
index 3fbeb8f0b..4e1fcca35 100644
--- a/libpod/define/container_inspect.go
+++ b/libpod/define/container_inspect.go
@@ -54,6 +54,9 @@ type InspectContainerConfig struct {
 	// CreateCommand is the full command plus arguments of the process the
 	// container has been created with.
 	CreateCommand []string `json:"CreateCommand,omitempty"`
+	// Timezone is the timezone inside the container.
+	// Local means it has the same timezone as the host machine
+	Timezone string `json:"Timezone,omitempty"`
 }
 
 // InspectRestartPolicy holds information about the container's restart policy.
diff --git a/libpod/options.go b/libpod/options.go
index 4041fb1cf..83d2c2e1f 100644
--- a/libpod/options.go
+++ b/libpod/options.go
@@ -1525,6 +1525,30 @@ func withSetAnon() VolumeCreateOption {
 	}
 }
 
+// WithTimezone sets the timezone in the container
+func WithTimezone(path string) CtrCreateOption {
+	return func(ctr *Container) error {
+		if ctr.valid {
+			return define.ErrCtrFinalized
+		}
+		if path != "local" {
+			zone := filepath.Join("/usr/share/zoneinfo", path)
+
+			file, err := os.Stat(zone)
+			if err != nil {
+				return err
+			}
+			//We don't want to mount a timezone directory
+			if file.IsDir() {
+				return errors.New("Invalid timezone: is a directory")
+			}
+		}
+
+		ctr.config.Timezone = path
+		return nil
+	}
+}
+
 // Pod Creation Options
 
 // WithPodName sets the name of the pod.