ut_control_plane: Overview (ut_control_plane.h)

Purpose:

This module provides a framework for building a "control plane" within a larger system. A control plane, typically:

• Monitors: Listens for incoming messages or events on a specific port.
• Reacts: Triggers pre-registered callback functions based on the content of received messages.
• Manages: Handles registration and unregistration of these callback functions.

Key Features:

• Initialization (UT_ControlPlane_Init):
  • Creates a control plane instance.
  • Specifies the network port to monitor.
• Callback Registration (UT_ControlPlane_RegisterCallbackOnMessage):
  • Associates specific message "keys" (strings) with callback functions.
  • When a message with a matching key is received, the corresponding callback is executed.
  • Supports user-defined data to be passed to the callback.
• Operation (UT_ControlPlane_Start, UT_ControlPlane_Stop):
  • Starts and stops the active monitoring process.
• Clean-up (UT_ControlPlane_Exit):
  • Releases all resources used by the control plane.

Data Structures:

• ut_controlPlane_instance_t: An opaque handle representing a control plane instance.
• ut_control_plane_status_t: An enumeration of possible status codes (success, failure reasons).
• ut_control_callback_t: A function pointer type defining the signature of a callback function.

Typical Usage:

1. Initialize: Create a control plane instance (UT_ControlPlane_Init).
2. Register Callbacks: For each type of message you want to handle, associate a callback function and optional user data (UT_ControlPlane_RegisterCallbackOnMessage).
3. Start: Begin listening for messages (UT_ControlPlane_Start).
4. (Internal operation) The control plane runs continuously, calling registered callbacks when matching messages arrive.
5. Stop (optional): If needed, pause message processing (UT_ControlPlane_Stop).
6. Exit: Clean up the control plane when finished (UT_ControlPlane_Exit).

Additional Notes:

• Maximum Callbacks: There's a limit of 32 registered callbacks (UT_CONTROL_PLANE_MAX_CALLBACK_ENTRIES).