[webOS] Fix timezone reading

[sundermann]

Description

Timezone was not set correctly on startup on webOS. Some refactoring is done first to avoid duplicating code. The diff is a bit large because clang format required fixing up the header inclusion order and variable spacing

Motivation and context

The webOS jailer only mounts /etc/localtime which is a symlink to /var/luna/preferences/localtime. /var/luna/preferences/localtime however is another symlink to the actual zone info.

How has this been tested?

webOS22/7

What is the effect on users?

Fixes timezone initialization

Screenshots (if appropriate):

Types of change

• Bug fix (non-breaking change which fixes an issue)
• Clean up (non-breaking change which removes non-working, unmaintained functionality)
• Improvement (non-breaking change which improves existing functionality)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that will cause existing functionality to change)
• Cosmetic change (non-breaking change that doesn't touch code)
• Student submission (PR was done for educational purposes and will be treated as such)
• None of the above (please explain below)

Checklist:

• My code follows the Code Guidelines of this project
• My change requires a change to the documentation, either Doxygen or wiki
• I have updated the documentation accordingly
• I have read the Contributing document
• I have added tests to cover my change
• All new and existing tests passed

[sundermann]

It seems std::filesystem is not available until macOS 10.15 and fstream is not available until NDK 24.

[throwaway96]

Information for webOS 4.1.0 (MStar M3 SoC, using the YouTube jail as an example):

/var/luna/preferences/timezone is present in the jail, but it's Universal instead of the system timezone (America/New_York):

root@lg-m3[m3 4.1.0]:~# cat /var/palm/jail/youtube.leanback.v4/var/luna/preferences/timezone
Universal

/etc/localtime is a symlink to /var/luna/preferences/localtime:

root@lg-m3[m3 4.1.0]:~# readlink /var/palm/jail/youtube.leanback.v4/etc/localtime
/var/luna/preferences/localtime

/var/luna/preferences/localtime (symlink to correct zoneinfo) is present in the jail:

root@lg-m3[m3 4.1.0]:~# readlink /var/palm/jail/youtube.leanback.v4/var/luna/preferences/localtime
/usr/share/zoneinfo/America/New_York

It seems that /usr/share/zoneinfo is available from inside the jail, e.g.:

  File: /var/palm/jail/youtube.leanback.v4/usr/share/zoneinfo/America/New_York
  Size: 3545            Blocks: 7          IO Block: 1024   regular file
Device: b31dh/45853d    Inode: 61542       Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2018-09-17 22:29:54.000000000
Modify: 2018-09-17 22:29:54.000000000
Change: 2018-09-17 22:29:54.000000000

These are the relevant lines in /etc/jail_native.conf (although I'm not sure exactly which configuration file is used, or how it's chosen, these lines seem to be common to all):

# /var/luna/preferences
mkdir /var/luna
mkdir /var/luna/preferences
mount ro /var/luna/preferences

link /var/luna/preferences/localtime /etc/localtime

/usr/share (apparently responsible for the existence of /usr/share/zoneinfo, although they mount /usr/share/fonts explicitly) is also mounted by jail_native.conf:

mount ro /usr/share

These files are the same outside of the jail. It looks like /var/luna/preferences/timezone has the wrong timezone setting. That may be an artifact of the strange way my webOS boards are configured (missed a firstuse step?), but I can look into it on other boards/versions.

[sundermann]

Thank you for checking this on different webOS versions. As you suggested I have changed to reading the symlink path from /var/luna/preferences/localtime instead

[wsnipex]

looks good to me

[jenkins4kodi]

I've made some formatting changes to meet the current code style. The diffs are available in the following links:

• PR23847-0002-6e4793f903-PosixTimezone-webOS-Use-realpath-t.diff
• PR23847.diff

For more information please see our current code style guidelines.