Part of the Lifecycle subsystem in GENIVI
The node state management is the central function for information regarding the current running state of the embedded system. The Node State Manager (NSM) component provides a common implementation framework for the main state machine of the system. The NSM collates information from multiple sources and uses this to determine the current state(s).
The NSM notifies registered consumers (applications or other platform components) of relevant changes in system state. Node state information can also be requested on-demand via provided D-Bus interfaces.
The node state management also provides shutdown management, so one part of the information which is provided is the shutdown request notification to the consumers.
The node state management is the last/highest level of escalation on the node and will therefore command the reset and supply control logic. It is notified of errors and other status signals from components that are responsible for monitoring system health in different ways.
Internally, node state management is made up of a common generic component, Node State Manager (NSM), and a system-specific state machine (NSMC) that is plugged into the Node State Manager. Through this architecture there can be a standardized solution with stable interfaces towards the applications, which still allows for product-specific behavior through the definition of the specific state machine.