// Copyright 2021 Nick Brassel (@tzarc) // SPDX-License-Identifier: GPL-2.0-or-later #pragma once #include <stdbool.h> #include <stdint.h> // A token that can be used to cancel an existing deferred execution. typedef uint8_t deferred_token; #define INVALID_DEFERRED_TOKEN 0 // Callback to execute. // -- Parameter trigger_time: the intended trigger time to execute the callback -- equivalent time-space as timer_read32() // cb_arg: the callback argument specified when enqueueing the deferred executor // -- Return value: Non-zero re-queues the callback to execute after the returned number of milliseconds. Zero cancels repeated execution. typedef uint32_t (*deferred_exec_callback)(uint32_t trigger_time, void *cb_arg); // Configures the supplied deferred executor to be executed after the required number of milliseconds. // -- Parameter delay_ms: the number of milliseconds before executing the callback // -- callback: the executor to invoke // -- cb_arg: the argument to pass to the executor, may be NULL if unused by the executor // -- Return value: a token usable for cancellation, or INVALID_DEFERRED_TOKEN if an error occurred deferred_token defer_exec(uint32_t delay_ms, deferred_exec_callback callback, void *cb_arg); // Allows for extending the timeframe before an existing deferred execution is invoked. // -- Parameter token: the returned value from defer_exec for the deferred execution you wish to extend. // -- delay_ms: the new delay (with respect to the current time) // -- Return value: if the token was found, and the delay was extended bool extend_deferred_exec(deferred_token token, uint32_t delay_ms); // Allows for cancellation of an existing deferred execution. // -- Parameter token: the returned value from defer_exec for the deferred execution you wish to cancel. // -- Return value: if the token was found, and the executor was cancelled bool cancel_deferred_exec(deferred_token token); // Forward declaration for the main loop in order to execute any deferred executors. Should not be invoked by keyboard/user code. void deferred_exec_task(void);