zephyr/include/microkernel/event.h

151 lines
3.9 KiB
C

/*
* Copyright (c) 1997-2014 Wind River Systems, Inc.
*
* 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.
*/
/**
* @file
* @brief Event header file.
*/
#ifndef EVENT_H
#define EVENT_H
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Microkernel Events
* @defgroup microkernel_event Microkernel Events
* @ingroup microkernel_services
* @{
*/
#include <microkernel/base_api.h>
/* well-known events */
extern const kevent_t TICK_EVENT;
/**
*
* @brief Signal an event from an ISR
*
* This routine does NOT validate the specified event number.
*
* @param event Event to signal.
*
* @return N/A
*/
extern void isr_event_send(kevent_t event);
/**
*
* @brief Signal an event from a fiber
*
* This routine does NOT validate the specified event number.
*
* @param event Event to signal.
*
* @return N/A
*/
extern void fiber_event_send(kevent_t event);
/**
*
* @brief Set event handler request
*
* This routine specifies the event handler that runs (in the context of the
* microkernel server fiber) when the associated event is signaled. Specifying
* a non-NULL handler installs a new handler, while specifying a NULL event
* handler removes the existing event handler.
*
* A new event handler cannot be installed if one already exists for that event;
* the old handler must be removed first. However, it is permitted to replace
* the NULL event handler with itself.
*
* @param event Event upon which to reigster.
* @param handler Function pointer to handler.
*
* @return RC_FAIL if an event handler exists or the event number is invalid,
* else RC_OK
*/
extern int task_event_handler_set(kevent_t event, kevent_handler_t handler);
/**
*
* @brief Signal an event request
*
* This routine signals the specified event from a task. If an event handler
* is installed for that event, it will run; if no event handler is installed,
* any task waiting on the event is released.
*
* @param event Event to signal.
*
* @return RC_FAIL if event number is invalid, else RC_OK
*/
extern int task_event_send(kevent_t event);
/**
*
* @brief Test for event request with timeout
*
* This routine tests an event to see if it has been signaled.
*
* @param event Event for which to test.
* @param timeout Affects the action taken should the event not yet be
* signaled. If TICKS_NONE, then return immediately. If TICKS_UNLIMITED, then
* wait as long as necessary. Otherwise wait up to the specified number of
* ticks before timing out.
*
* @retval RC_OK Successfully received signaled event
* @retval RC_TIME Timed out while waiting for signaled event
* @retval RC_FAIL Failed to immediately receive signaled event when
* @a timeout = TICKS_NONE
*/
extern int task_event_recv(kevent_t event, int32_t timeout);
/**
* @}
*/
#define _K_EVENT_INITIALIZER(handler) \
{ \
.status = 0, \
.func = (kevent_handler_t)handler, \
.waiter = NULL, \
.count = 0, \
}
/**
* @brief Define a private microkernel event
*
* This declares and initializes a private event. The new event
* can be passed to the microkernel event functions.
*
* @param name Name of the event
* @param handler Function to handle the event (can be NULL)
*/
#define DEFINE_EVENT(name, handler) \
struct _k_event_struct _k_event_obj_##name \
__in_section(_k_event_list, event, name) = \
_K_EVENT_INITIALIZER(handler); \
const kevent_t name = (kevent_t)&_k_event_obj_##name;
#ifdef __cplusplus
}
#endif
#endif /* EVENT_H */