EventFlags.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2017 ARM Limited
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00020  * SOFTWARE.
00021  */
00022 #ifndef EVENT_FLAG_H
00023 #define EVENT_FLAG_H
00024 
00025 #include <stdint.h>
00026 #include "cmsis_os2.h"
00027 #include "mbed_rtos1_types.h"
00028 #include "mbed_rtos_storage.h"
00029 
00030 #include "platform/NonCopyable.h"
00031 
00032 namespace rtos {
00033 /** \addtogroup rtos */
00034 /** @{*/
00035 /**
00036  * \defgroup rtos_EventFlags EventFlags class
00037  * @{
00038  */
00039  
00040 /** The EventFlags class is used to control event flags or wait for event flags other threads control.
00041 
00042  @note 
00043  EventFlags support 31 flags. The MSB flag is ignored. It is used to return an error code (@a osFlagsError).
00044 
00045  @note
00046  Memory considerations: The EventFlags control structures will be created on the current thread's stack, both for the Mbed OS
00047  and underlying RTOS objects (static or dynamic RTOS memory pools are not being used).
00048 */
00049 class EventFlags : private mbed::NonCopyable<EventFlags> {
00050 public:
00051     /** Create and initialize an EventFlags object.
00052      *
00053      * @note You cannot call this function from ISR context.
00054     */
00055     EventFlags();
00056 
00057     /** Create and initialize an EventFlags object.
00058 
00059      @param name name to be used for this EventFlags. It has to stay allocated for the lifetime of the thread.
00060 
00061      @note You cannot call this function from ISR context.
00062     */
00063     EventFlags(const char *name);
00064 
00065     /** Set the specified event flags.
00066       @param   flags the flags that will be set.
00067       @return  event flags after setting or error code if highest bit set (see @a osFlagsError for details).
00068 
00069       @note This function may be called from ISR context.
00070      */
00071     uint32_t set(uint32_t flags);
00072 
00073     /** Clear the specified event flags.
00074       @param   flags the flags that will be cleared (default: 0x7fffffff -- all flags).
00075       @return  event flags before clearing or error code if highest bit set (see @a osFlagsError for details).
00076 
00077       @note You may call this function from ISR context.
00078      */
00079     uint32_t clear(uint32_t flags = 0x7fffffff);
00080 
00081     /** Get the currently set event flags.
00082       @return  current event flags.
00083 
00084       @note You may call this function from ISR context.
00085      */
00086     uint32_t get() const;
00087 
00088     /** Wait for all of the specified event flags to become signaled.
00089       @param   flags    the flags to wait for (default: 0 -- no flags).
00090       @param   timeout  timeout value or 0 in case of no time-out (default: osWaitForever).
00091       @param   clear    clear specified event flags after waiting for them (default: true).
00092       @return  event flags before clearing or error code if highest bit set (see @a osFlagsError for details).
00093 
00094       @note You may call this function from ISR context if the timeout parameter is set to 0.
00095      */
00096     uint32_t wait_all(uint32_t flags = 0, uint32_t timeout = osWaitForever, bool clear = true);
00097 
00098     /** Wait for any of the specified event flags to become signaled.
00099       @param   flags    the flags to wait for (default: 0 -- no flags).
00100       @param   timeout  timeout value or 0 in case of no timeout (default: osWaitForever).
00101       @param   clear    clear specified event flags after waiting for them (default: true).
00102       @return  event flags before clearing or error code if highest bit set (see @a osFlagsError for details).
00103 
00104       @note This function may be called from ISR context if the timeout parameter is set to 0.
00105      */
00106     uint32_t wait_any(uint32_t flags = 0, uint32_t timeout = osWaitForever, bool clear = true);
00107 
00108     /** EventFlags destructor.
00109 
00110       @note You cannot call this function from ISR context.
00111     */
00112     ~EventFlags();
00113 
00114 private:
00115     void constructor(const char *name = NULL);
00116     uint32_t wait(uint32_t flags, uint32_t opt, uint32_t timeout, bool clear);
00117     osEventFlagsId_t                _id;
00118     mbed_rtos_storage_event_flags_t _obj_mem;
00119 };
00120 
00121 /** @}*/
00122 /** @}*/
00123 
00124 }
00125 #endif
00126