System State Management Architecture Overview

Purpose

SSMA provides a generic an a customizable mechanism to control the state of the system such as the activities to be performed at the start-up of the device, the order in which activities are executed or the actions to be performed at shut-down of the device.

Architecture

The following image shows the System State Management Architecture.

Figure 1. SSMA Architecture

Description

System State Manager and System State Plug-in together constitute the architecture of SSMA.

• The SSM client sends a state or a system wide-proeprty transition request to the System State Manager server (SysState.exe), SysState.exe loads the policy plug-in using the policy plug-in interfaces. The state policy plug-in consists of command list. The command list has the substates defined. The SysState.exe calls the command list executer using the SSM CLE interface. System Command List Executer (SysCLE) contains a list of commands that are executed by the SSM.

• System State Manager Utility Server (SUS) receives a request from the SSM client. SUS is responsible to monitor and control the system-wide property changes.

  SUS loads the utility plug-in using the SSM Utility plug-in interface. The policy DLL will be dynamically loaded and an object will be instantiated that will implement one of the interfaces (M Class).

• System State Manager Adaptation Server (SAS) receives a request from the SSM client. SAS is responsible for security checks, admission control and multiplexing and de-multiplexing of requests to and from the adaptation plug-in interfaces.

  The SSM adaptation server will create the adaptation classes by calling the first ordinal in the adaptation.dll. The different types of Adaptation plug-in are Emergency Call RF adaptation, Miscellaneous adaptation, SIM adaptation, state adaptation and RTC adaptation plug-in and use the EmergencyCallRfAdaptation, MiscAdaptation, SimAdaptation, StateAdaptation and RtcAdaptation interfaces respectively.

  All the interfaces are implemented by the corresponding R classes exposed from the SSM adaptation server. This allows custom commands and other components in the system with appropriate capabilities to access the functionality provided in these adaptation interfaces.

Components

• System State Manager: System State Manager (SSM) is a Symbian platform component that manages the state of a system throughout its lifecycle. The SSM extends the existing Generic Start-up Architecture (GSA) to manage the whole system lifecycle.

• System State plug-in: The system state plug-in framework provides interfaces suitable for interpreting the conditional resource files. It also provides interfaces which allow customisation of the behaviour of state and system wide property changes.