mirror of https://github.com/ARMmbed/mbed-os.git
182 lines
6.5 KiB
C++
182 lines
6.5 KiB
C++
/* mbed Microcontroller Library
|
|
* Copyright (c) 2006-2012 ARM Limited
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
* SOFTWARE.
|
|
*/
|
|
#ifndef MUTEX_H
|
|
#define MUTEX_H
|
|
|
|
#include <stdint.h>
|
|
#include "cmsis_os2.h"
|
|
#include "mbed_rtos1_types.h"
|
|
#include "mbed_rtos_storage.h"
|
|
|
|
#include "platform/NonCopyable.h"
|
|
#include "platform/ScopedLock.h"
|
|
#include "platform/mbed_toolchain.h"
|
|
|
|
namespace rtos {
|
|
/** \addtogroup rtos */
|
|
/** @{*/
|
|
|
|
class Mutex;
|
|
/** Typedef for the mutex lock
|
|
*
|
|
* Usage:
|
|
* @code
|
|
* void foo(Mutex &m) {
|
|
* ScopedMutexLock lock(m);
|
|
* // Mutex lock protects code in this block
|
|
* }
|
|
* @endcode
|
|
*/
|
|
typedef mbed::ScopedLock<Mutex> ScopedMutexLock;
|
|
|
|
/**
|
|
* \defgroup rtos_Mutex Mutex class
|
|
* @{
|
|
*/
|
|
|
|
/** The Mutex class is used to synchronize the execution of threads.
|
|
This is for example used to protect access to a shared resource.
|
|
|
|
@note You cannot use member functions of this class in ISR context. If you require Mutex functionality within
|
|
ISR handler, consider using @a Semaphore.
|
|
|
|
@note
|
|
Memory considerations: The mutex control structures will be created on current thread's stack, both for the Mbed OS
|
|
and underlying RTOS objects (static or dynamic RTOS memory pools are not being used).
|
|
*/
|
|
class Mutex : private mbed::NonCopyable<Mutex> {
|
|
public:
|
|
/** Create and Initialize a Mutex object
|
|
*
|
|
* @note You cannot call this function from ISR context.
|
|
*/
|
|
Mutex();
|
|
|
|
/** Create and Initialize a Mutex object
|
|
|
|
@param name name to be used for this mutex. It has to stay allocated for the lifetime of the thread.
|
|
@note You cannot call this function from ISR context.
|
|
*/
|
|
Mutex(const char *name);
|
|
|
|
/**
|
|
Wait until a Mutex becomes available.
|
|
|
|
@return status code that indicates the execution status of the function:
|
|
@a osOK the mutex has been obtained.
|
|
|
|
@note You cannot call this function from ISR context.
|
|
@note This function treats RTOS errors as fatal system errors, so can only return osOK.
|
|
Use of the return value is deprecated, as the return is expected to become void in the future.
|
|
*/
|
|
osStatus lock(void);
|
|
|
|
/**
|
|
For backwards compatibility.
|
|
@deprecated Do not use this function. This function has been replaced with lock(), trylock() and trylock_for() functions.
|
|
|
|
Wait until a Mutex becomes available.
|
|
@param millisec timeout value or 0 in case of no time-out.
|
|
@return status code that indicates the execution status of the function:
|
|
@a osOK the mutex has been obtained.
|
|
@a osErrorTimeout the mutex could not be obtained in the given time.
|
|
@a osErrorResource the mutex could not be obtained when no timeout was specified.
|
|
|
|
@note You cannot call this function from ISR context.
|
|
@note This function treats RTOS errors as fatal system errors, so can only return osOK or
|
|
osErrorResource in case when millisec is 0 or osErrorTimeout if millisec is not osWaitForever.
|
|
*/
|
|
MBED_DEPRECATED_SINCE("mbed-os-5.10.0", "Replaced with lock(), trylock() and trylock_for() functions")
|
|
osStatus lock(uint32_t millisec);
|
|
|
|
/** Try to lock the mutex, and return immediately
|
|
@return true if the mutex was acquired, false otherwise.
|
|
@note equivalent to trylock_for(0)
|
|
|
|
@note You cannot call this function from ISR context.
|
|
*/
|
|
bool trylock();
|
|
|
|
/** Try to lock the mutex for a specified time
|
|
@param millisec timeout value or 0 in case of no time-out.
|
|
@return true if the mutex was acquired, false otherwise.
|
|
@note the underlying RTOS may have a limit to the maximum wait time
|
|
due to internal 32-bit computations, but this is guaranteed to work if the
|
|
wait is <= 0x7fffffff milliseconds (~24 days). If the limit is exceeded,
|
|
the lock attempt will time out earlier than specified.
|
|
|
|
@note You cannot call this function from ISR context.
|
|
*/
|
|
bool trylock_for(uint32_t millisec);
|
|
|
|
/** Try to lock the mutex until specified time
|
|
@param millisec absolute timeout time, referenced to Kernel::get_ms_count()
|
|
@return true if the mutex was acquired, false otherwise.
|
|
@note the underlying RTOS may have a limit to the maximum wait time
|
|
due to internal 32-bit computations, but this is guaranteed to work if the
|
|
wait is <= 0x7fffffff milliseconds (~24 days). If the limit is exceeded,
|
|
the lock attempt will time out earlier than specified.
|
|
|
|
@note You cannot call this function from ISR context.
|
|
*/
|
|
bool trylock_until(uint64_t millisec);
|
|
|
|
/**
|
|
Unlock the mutex that has previously been locked by the same thread
|
|
|
|
@return status code that indicates the execution status of the function:
|
|
@a osOK the mutex has been released.
|
|
|
|
@note You cannot call this function from ISR context.
|
|
@note This function treats RTOS errors as fatal system errors, so can only return osOK.
|
|
Use of the return value is deprecated, as the return is expected to become void in the future.
|
|
*/
|
|
osStatus unlock();
|
|
|
|
/** Get the owner the this mutex
|
|
@return the current owner of this mutex.
|
|
|
|
@note You cannot call this function from ISR context.
|
|
*/
|
|
osThreadId get_owner();
|
|
|
|
/** Mutex destructor
|
|
*
|
|
* @note You cannot call this function from ISR context.
|
|
*/
|
|
~Mutex();
|
|
|
|
private:
|
|
void constructor(const char *name = NULL);
|
|
friend class ConditionVariable;
|
|
|
|
osMutexId_t _id;
|
|
mbed_rtos_storage_mutex_t _obj_mem;
|
|
uint32_t _count;
|
|
};
|
|
/** @}*/
|
|
/** @}*/
|
|
}
|
|
#endif
|
|
|
|
|