Import of the watch repository from Pebble

src/fw/applib/app_timer.h

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+/*
+ * Copyright 2024 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+//! @addtogroup Foundation
+//! @{
+//!   @addtogroup Timer
+//!   \brief Can be used to execute some code at some point in the future.
+//!   @{
+
+//! An opaque handle to a timer
+struct AppTimer;
+typedef struct AppTimer AppTimer;
+
+//! The type of function which can be called when a timer fires.  The argument will be the @p callback_data passed to
+//! @ref app_timer_register().
+typedef void (*AppTimerCallback)(void* data);
+
+//! Registers a timer that ends up in callback being called some specified time in the future.
+//! @param timeout_ms The expiry time in milliseconds from the current time
+//! @param callback The callback that gets called at expiry time
+//! @param callback_data The data that will be passed to callback
+//! @return A pointer to an `AppTimer` that can be used to later reschedule or cancel this timer
+AppTimer* app_timer_register(uint32_t timeout_ms, AppTimerCallback callback, void* callback_data);
+
+//! @internal
+//! Registers a timer that ends up in callback being called repeatedly at a specified interval
+//! @param timeout_ms The interval time in milliseconds from the current time
+//! @param callback The callback that gets called at every interval
+//! @param callback_data The data that will be passed to callback
+//! @return A pointer to an `AppTimer` that can be used to later reschedule or cancel this timer
+AppTimer* app_timer_register_repeatable(uint32_t timeout_ms,
+                                        AppTimerCallback callback,
+                                        void* callback_data,
+                                        bool repeating);
+
+//! @internal
+//! Get the data passed to the app timer
+void *app_timer_get_data(AppTimer *timer);
+
+//! Reschedules an already running timer for some point in the future.
+//! @param timer_handle The timer to reschedule
+//! @param new_timeout_ms The new expiry time in milliseconds from the current time
+//! @return true if the timer was rescheduled, false if the timer has already elapsed
+bool app_timer_reschedule(AppTimer *timer_handle, uint32_t new_timeout_ms);
+
+//! Cancels an already registered timer.
+//! Once cancelled the handle may no longer be used for any purpose.
+void app_timer_cancel(AppTimer *timer_handle);
+
+//!   @} // group Timer
+//! @} // group Foundation
+