Timezone: Support for FreeBSD/NetBSD and improve SmartOS handling (#20268)

* Tweaks for SmartOS:

- prevent attempting from changing timezone in the global zone (read-only)
- provide meaningful error message in the unlikely case smtools isn't present

* Add support for FreeBSD and NetBSD to timezone module

lib/ansible/modules/system/timezone.py

@@ -38,15 +38,15 @@ module: timezone
 short_description: Configure timezone setting
 description:
   - This module configures the timezone setting, both of the system clock
-    and of the hardware clock. I(Currently only Linux, OpenBSD and SmartOS
+    and of the hardware clock. I(Currently only Linux, FreeBSD, NetBSD,
-    instances are supported.)
+    OpenBSD and SmartOS instances are supported.)
     It is recommended to restart C(crond) after changing the timezone,
     otherwise the jobs may run at the wrong time.
     On Linux it uses the C(timedatectl) command if available. Otherwise,
     it edits C(/etc/sysconfig/clock) or C(/etc/timezone) for the system clock,
     and uses the C(hwclock) command for the hardware clock.
     On SmartOS the C(sm-set-timezone) utility is used to set the zone timezone,
-    and on OpenBSD C(/etc/localtime) is modified.
+    and on *BSD, C(/etc/localtime) is modified.
     If you want to set up the NTP, use M(service) module.
 version_added: "2.2"
 options:
@@ -117,12 +117,17 @@ class Timezone(object):
                 return super(Timezone, NosystemdTimezone).__new__(NosystemdTimezone)
         elif re.match('^joyent_.*Z', platform.version()):
             # get_platform() returns SunOS, which is too broad. So look at the
-            # platform version instead.
+            # platform version instead. However we have to ensure that we're not
+            # running in the global zone where changing the timezone has no effect.
+            zonename_cmd = module.get_bin_path('zonename')
+            if zonename_cmd is not None:
+                (rc, stdout, _ ) = module.run_command(zonename_cmd)
+                if rc == 0 and stdout.strip() == 'global':
+                    module.fail_json(msg='Adjusting timezone is not supported in Global Zone')
+
             return super(Timezone, SmartOSTimezone).__new__(SmartOSTimezone)
-        elif re.match('^OpenBSD', platform.platform()):
+        elif re.match('^(Free|Net|Open)BSD', platform.platform()):
-            # This might be too specific for now, however it can then serve as
+            return super(Timezone, BSDTimezone).__new__(BSDTimezone)
-            # a generic base for /etc/localtime honoring Unix-like systems.
-            return super(Timezone, OpenBSDTimezone).__new__(OpenBSDTimezone)
         else:
             # Not supported yet
             return super(Timezone, Timezone).__new__(Timezone)
@@ -460,7 +465,9 @@ class SmartOSTimezone(Timezone):
 
     def __init__(self, module):
         super(SmartOSTimezone, self).__init__(module)
-        self.settimezone = self.module.get_bin_path('sm-set-timezone', required=True)
+        self.settimezone = self.module.get_bin_path('sm-set-timezone', required=False)
+        if not self.settimezone:
+            module.fail_json(msg='sm-set-timezone not found. Make sure the smtools package is installed.')
 
     def get(self, key, phase):
         """Lookup the current timezone name in `/etc/default/init`. If anything else
@@ -500,14 +507,14 @@ class SmartOSTimezone(Timezone):
                                   format(key))
 
 
-class OpenBSDTimezone(Timezone):
+class BSDTimezone(Timezone):
-    """This is the timezone implementation for OpenBSD which works simply through
+    """This is the timezone implementation for *BSD which works simply through
     updating the `/etc/localtime` symlink to point to a valid timezone name under
     `/usr/share/zoneinfo`.
     """
 
     def __init__(self, module):
-        super(OpenBSDTimezone, self).__init__(module)
+        super(BSDTimezone, self).__init__(module)
 
     def get(self, key, phase):
         """Lookup the current timezone by resolving `/etc/localtime`."""