Struct LogCallbackManager 

pub struct LogCallbackManager { /* private fields */ }

Manager for FFI log callbacks

Each plugin can register its own log callback. The callback is cleared when the plugin that registered it shuts down to prevent use-after-free (the callback function pointer is tied to the plugin’s FFI arena lifetime).

Log level is shared globally and persists across plugin reload cycles.

Implementations

impl LogCallbackManager

pub fn new() -> Self

Create a new callback manager

pub fn global() -> &'static LogCallbackManager

Get the global callback manager instance

pub fn set_callback(&self, callback: Option<LogCallback>)

Set the log callback

pub fn register_plugin(&self, callback: Option<LogCallback>)

Register a plugin with the callback manager

This increments the reference count and optionally sets the callback. If a callback is provided, it replaces any existing callback.

Important: The callback function pointer is tied to the plugin’s FFI arena lifetime. When the plugin shuts down, the callback becomes invalid and must be cleared before the arena is closed.

This should be called during plugin initialization.

pub fn unregister_plugin(&self)

Unregister a plugin from the callback manager

Critical: This ALWAYS clears the callback to prevent use-after-free. The callback function pointer is tied to the plugin’s FFI arena, which will be closed immediately after this function returns. If we didn’t clear the callback, any subsequent logging would call an invalid pointer.

This means that with multiple plugins, the last one to unregister will disable logging for any remaining plugins until they re-register a callback. This is a safety trade-off: we prioritize crash prevention over convenience.

Note: The reload handle is NOT cleared because logging initialization only happens once per process. The reload handle must persist across plugin reload cycles.

This should be called during plugin shutdown.

pub fn plugin_count(&self) -> usize

Get the current reference count (number of active plugins)

pub fn get_callback(&self) -> Option<LogCallback>

Get the current log callback

pub fn set_level(&self, level: LogLevel)

Set the log level

pub fn level(&self) -> LogLevel

Get the current log level

pub fn is_enabled(&self, level: LogLevel) -> bool

Check if a log level is enabled

pub fn log(&self, level: LogLevel, target: &str, message: &str)

Invoke the callback if set and level is enabled

Safety

The callback must be a valid function pointer that follows the LogCallback signature contract.

Trait Implementations

impl Default for LogCallbackManager

fn default() -> Self

Returns the “default value” for a type.

impl Send for LogCallbackManager

impl Sync for LogCallbackManager