Add support for restart command in Windows Agent

[aritosteles]

Description

This PR enables the Wazuh agent to support a command for self-restart in Windows.

Proposed Changes

• Devise a strategy to restart the Agent when running as a service. Windows Service Control does not offer a restart command like launchd or systemd do. This is problematic since the service cannot restart itself using a simple sequence of stop/start because it is stopped before it has a chance to start another instance of itself. The desired functionality can be achieved by leveraging Powershell command Restart-Service, running through a call to Win32 function CreateProcess().
• Devise a strategyto restart the Agent when running in the foreground. This presents a problem similar to the one described in the previous case because we are not running a separate process to do the restart. The problem can be solved by a call to 'cmd' before stopping the Agent. The instance of cmd will delay for some time to allow the running Agent to gracefully shutdown before starting a new instance.

Results and Evidence

• Agent restarted while running as a service:

Full sequence of events:

event log.txt

• Agent restarted while running in the foreground:

Artifacts Affected

• Windows executable

Configuration Changes

None

Documentation Updates

None

Tests Introduced

Review Checklist

• Code changes reviewed
• Relevant evidence provided
• Tests cover the new functionality
• Configuration changes documented
• Developer documentation reflects the changes
• Meets requirements and/or definition of done
• No unresolved dependencies with other issues
• ...

[jr0me]

Will this only work if windows has powershell? I ask because I'm not sure that it is always available.

[aritosteles]

Will this only work if windows has powershell? I ask because I'm not sure that it is always available.

Windows Powershell has been bundled since Windows XP SP3 and can be installed on earlier versions of XP. Should this be a concern?

[jr0me]

Windows Powershell has been bundled since Windows XP SP3 and can be installed on earlier versions of XP. Should this be a concern?

Not necessarily, but if it's not bundled in any of the Windows versions we support, it should be added to the requirements list or to the documentation.

[jr0me]

LGTM!