// Copyright 2018 Espressif Systems (Shanghai) PTE LTD
//
// 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.
#ifndef ESP_EVENT_H_
#define ESP_EVENT_H_
#include "esp_err.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "freertos/semphr.h"
#include "esp_event_base.h"
#include "esp_event_legacy.h"
#ifdef __cplusplus
extern "C" {
#endif
/// Configuration for creating event loops
typedef struct {
int32_t queue_size; /**< size of the event loop queue */
const char* task_name; /**< name of the event loop task; if NULL,
a dedicated task is not created for event loop*/
UBaseType_t task_priority; /**< priority of the event loop task, ignored if task name is NULL */
uint32_t task_stack_size; /**< stack size of the event loop task, ignored if task name is NULL */
BaseType_t task_core_id; /**< core to which the event loop task is pinned to,
ignored if task name is NULL */
} esp_event_loop_args_t;
/**
* @brief Create a new event loop.
*
* @param[in] event_loop_args configuration structure for the event loop to create
* @param[out] event_loop handle to the created event loop
*
* @return
* - ESP_OK: Success
* - ESP_ERR_NO_MEM: Cannot allocate memory for event loops list
* - ESP_FAIL: Failed to create task loop
* - Others: Fail
*/
esp_err_t esp_event_loop_create(const esp_event_loop_args_t* event_loop_args, esp_event_loop_handle_t* event_loop);
/**
* @brief Delete an existing event loop.
*
* @param[in] event_loop event loop to delete
*
* @return
* - ESP_OK: Success
* - Others: Fail
*/
esp_err_t esp_event_loop_delete(esp_event_loop_handle_t event_loop);
/**
* @brief Create default event loop
*
* @return
* - ESP_OK: Success
* - ESP_ERR_NO_MEM: Cannot allocate memory for event loops list
* - ESP_FAIL: Failed to create task loop
* - Others: Fail
*/
esp_err_t esp_event_loop_create_default();
/**
* @brief Delete the default event loop
*
* @return
* - ESP_OK: Success
* - Others: Fail
*/
esp_err_t esp_event_loop_delete_default();
/**
* @brief Dispatch events posted to an event loop.
*
* This function is used to dispatch events posted to a loop with no dedicated task, i.e task name was set to NULL
* in event_loop_args argument during loop creation. This function includes an argument to limit the amount of time
* it runs, returning control to the caller when that time expires (or some time afterwards). There is no guarantee
* that a call to this function will exit at exactly the time of expiry. There is also no guarantee that events have
* been dispatched during the call, as the function might have spent all of the alloted time waiting on the event queue.
* Once an event has been unqueued, however, it is guaranteed to be dispatched. This guarantee contributes to not being
* able to exit exactly at time of expiry as (1) blocking on internal mutexes is necessary for dispatching the unqueued
* event, and (2) during dispatch of the unqueued event there is no way to control the time occupied by handler code
* execution. The guaranteed time of exit is therefore the alloted time + amount of time required to dispatch
* the last unqueued event.
*
* In cases where waiting on the queue times out, ESP_OK is returned and not ESP_ERR_TIMEOUT, since it is
* normal behavior.
*
* @param[in] event_loop event loop to dispatch posted events from
* @param[in] ticks_to_run number of ticks to run the loop
*
* @note encountering an unknown event that has been posted to the loop will only generate a warning, not an error.
*
* @return
* - ESP_OK: Success
* - Others: Fail
*/
esp_err_t esp_event_loop_run(esp_event_loop_handle_t event_loop, TickType_t ticks_to_run);
/**
* @brief Register an event handler to the system event loop.
*
* This function can be used to register a handler for either: (1) specific events,
* (2) all events of a certain event base, or (3) all events known by the system event loop.
*
* - specific events: specify exact event_base and event_id
* - all events of a certain base: specify exact event_base and use ESP_EVENT_ANY_ID as the event_id
* - all events known by the loop: use ESP_EVENT_ANY_BASE for event_base and ESP_EVENT_ANY_ID as the event_id
*
* Registering multiple handlers to events is possible. Registering a single handler to multiple events is
* also possible. However, registering the same handler to the same event multiple times would cause the
* previous registrations to be overwritten.
*
* @param[in] event_base the base id of the event to register the handler for
* @param[in] event_id the id of the event to register the handler for
* @param[in] event_handler the handler function which gets called when the event is dispatched
* @param[in] event_handler_arg data, aside from event data, that is passed to the handler when it is called
*
* @note the event loop library does not maintain a copy of event_handler_arg, therefore the user should
* ensure that event_handler_arg still points to a valid location by the time the handler gets called
*
* @return
* - ESP_OK: Success
* - ESP_ERR_NO_MEM: Cannot allocate memory for the handler
* - ESP_ERR_INVALID_ARG: Invalid combination of event base and event id
* - Others: Fail
*/
esp_err_t esp_event_handler_register(esp_event_base_t event_base,
int32_t event_id,
esp_event_handler_t event_handler,
void* event_handler_arg);
/**
* @brief Register an event handler to a specific loop.
*
* This function behaves in the same manner as esp_event_handler_register, except the additional
* specification of the event loop to register the handler to.
*
* @param[in] event_loop the event loop to register this handler function to
* @param[in] event_base the base id of the event to register the handler for
* @param[in] event_id the id of the event to register the handler for
* @param[in] event_handler the handler function which gets called when the event is dispatched
* @param[in] event_handler_arg data, aside from event data, that is passed to the handler when it is called
*
* @note the event loop library does not maintain a copy of event_handler_arg, therefore the user should
* ensure that event_handler_arg still points to a valid location by the time the handler gets called
*
* @return
* - ESP_OK: Success
* - ESP_ERR_NO_MEM: Cannot allocate memory for the handler
* - ESP_ERR_INVALID_ARG: Invalid combination of event base and event id
* - Others: Fail
*/
esp_err_t esp_event_handler_register_with(esp_event_loop_handle_t event_loop,
esp_event_base_t event_base,
int32_t event_id,
esp_event_handler_t event_handler,
void* event_handler_arg);
/**
* @brief Unregister a handler with the system event loop.
*
* This function can be used to unregister a handler so that it no longer gets called during dispatch.
* Handlers can be unregistered for either: (1) specific events, (2) all events of a certain event base,
* or (3) all events known by the system event loop
*
* - specific events: specify exact event_base and event_id
* - all events of a certain base: specify exact event_base and use ESP_EVENT_ANY_ID as the event_id
* - all events known by the loop: use ESP_EVENT_ANY_BASE for event_base and ESP_EVENT_ANY_ID as the event_id
*
* This function ignores unregistration of handlers that has not been previously registered.
*
* @param[in] event_base the base of the event with which to unregister the handler
* @param[in] event_id the id of the event with which to unregister the handler
* @param[in] event_handler the handler to unregister
*
* @return ESP_OK success
* @return ESP_ERR_INVALID_ARG invalid combination of event base and event id
* @return others fail
*/
esp_err_t esp_event_handler_unregister(esp_event_base_t event_base, int32_t event_id, esp_event_handler_t event_handler);
/**
* @brief Unregister a handler with the system event loop.
*
* This function behaves in the same manner as esp_event_handler_unregister, except the additional specification of
* the event loop to unregister the handler with.
*
* @param[in] event_loop the event loop with which to unregister this handler function
* @param[in] event_base the base of the event with which to unregister the handler
* @param[in] event_id the id of the event with which to unregister the handler
* @param[in] event_handler the handler to unregister
*
* @return
* - ESP_OK: Success
* - ESP_ERR_INVALID_ARG: Invalid combination of event base and event id
* - Others: Fail
*/
esp_err_t esp_event_handler_unregister_with(esp_event_loop_handle_t event_loop,
esp_event_base_t event_base,
int32_t event_id,
esp_event_handler_t event_handler);
/**
* @brief Posts an event to the system default event loop. The event loop library keeps a copy of event_data and manages
* the copy's lifetime automatically (allocation + deletion); this ensures that the data the
* handler recieves is always valid.
*
* @param[in] event_base the event base that identifies the event
* @param[in] event_id the the event id that identifies the event
* @param[in] event_data the data, specific to the event occurence, that gets passed to the handler
* @param[in] event_data_size the size of the event data
* @param[in] ticks_to_wait number of ticks to block on a full event queue
*
* @note posting events from an ISR is not supported
*
* @return
* - ESP_OK: Success
* - ESP_ERR_TIMEOUT: Time to wait for event queue to unblock expired
* - ESP_ERR_INVALID_ARG: Invalid combination of event base and event id
* - Others: Fail
*/
esp_err_t esp_event_post(esp_event_base_t event_base,
int32_t event_id,
void* event_data,
size_t event_data_size,
TickType_t ticks_to_wait);
/**
* @brief Posts an event to the specified event loop. The event loop library keeps a copy of event_data and manages
* the copy's lifetime automatically (allocation + deletion); this ensures that the data the
* handler recieves is always valid.
*
* This function behaves in the same manner as esp_event_post_to, except the additional specification of the event loop
* to post the event to.
*
* @param[in] event_loop the event loop to post to
* @param[in] event_base the event base that identifies the event
* @param[in] event_id the the event id that identifies the event
* @param[in] event_data the data, specific to the event occurence, that gets passed to the handler
* @param[in] event_data_size the size of the event data
* @param[in] ticks_to_wait number of ticks to block on a full event queue
*
* @note posting events from an ISR is not supported
*
* @return
* - ESP_OK: Success
* - ESP_ERR_TIMEOUT: Time to wait for event queue to unblock expired
* - ESP_ERR_INVALID_ARG: Invalid combination of event base and event id
* - Others: Fail
*/
esp_err_t esp_event_post_to(esp_event_loop_handle_t event_loop,
esp_event_base_t event_base,
int32_t event_id,
void* event_data,
size_t event_data_size,
TickType_t ticks_to_wait);
/**
* @brief Dumps statistics of all event loops.
*
* Dumps event loop info in the format:
*
@verbatim
event loop
handler
handler
...
event loop
handler
handler
...
where:
event loop
format: address,name rx:total_recieved dr:total_dropped
where:
address - memory address of the event loop
name - name of the event loop, 'none' if no dedicated task
total_recieved - number of successfully posted events
total_dropped - number of events unsucessfully posted due to queue being full
handler
format: address ev:base,id inv:total_invoked run:total_runtime
where:
address - address of the handler function
base,id - the event specified by event base and id this handler executes
total_invoked - number of times this handler has been invoked
total_runtime - total amount of time used for invoking this handler
@endverbatim
*
* @param[in] file the file stream to output to
*
* @note this function is a noop when CONFIG_EVENT_LOOP_PROFILING is disabled
*
* @return
* - ESP_OK: Success
* - ESP_ERR_NO_MEM: Cannot allocate memory for event loops list
* - Others: Fail
*/
esp_err_t esp_event_dump(FILE* file);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // #ifndef ESP_EVENT_H_