Line-Following-Robot/Input/Externals/raspicam-master/dependencies/vcos/vcos_quickslow_mutex.h

/*
Copyright (c) 2012, Broadcom Europe Ltd
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
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      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    * Neither the name of the copyright holder nor the
      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.

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ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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*/

/*=============================================================================
VideoCore OS Abstraction Layer - mutex public header file
=============================================================================*/

#ifndef VCOS_QUICKSLOW_MUTEX_H
#define VCOS_QUICKSLOW_MUTEX_H

#ifdef __cplusplus
extern "C" {
#endif

#include "vcos_types.h"
#include "pthreads/vcos_platform.h"

/**
 * \file vcos_quickslow_mutex.h
 *
 * "Quick/Slow" Mutex API. This is a mutex which supports an additional "quick"
 * (spinlock-based) locking mechanism. While in this quick locked state, other
 * operating system commands will be unavailable and the caller should complete
 * whatever it has to do in a short, bounded length of time (as the spinlock
 * completely locks out other system activity).
 *
 * \sa vcos_mutex.h
 *
 */

/** Create a mutex.
  *
  * @param m      Filled in with mutex on return
  * @param name   A non-null name for the mutex, used for diagnostics.
  *
  * @return VCOS_SUCCESS if mutex was created, or error code.
  */
VCOS_INLINE_DECL
VCOS_STATUS_T vcos_quickslow_mutex_create(VCOS_QUICKSLOW_MUTEX_T *m, const char *name);

/** Delete the mutex.
  */
VCOS_INLINE_DECL
void vcos_quickslow_mutex_delete(VCOS_QUICKSLOW_MUTEX_T *m);

/**
  * \brief Wait to claim the mutex ("slow" mode).
  *
  * Obtain the mutex.
  */
VCOS_INLINE_DECL
void vcos_quickslow_mutex_lock(VCOS_QUICKSLOW_MUTEX_T *m);

/** Release the mutex ("slow" mode).
  */
VCOS_INLINE_DECL
void vcos_quickslow_mutex_unlock(VCOS_QUICKSLOW_MUTEX_T *m);

/**
  * \brief Wait to claim the mutex ("quick" mode).
  *
  * Obtain the mutex. The caller must not call any OS functions or do anything
  * "slow" before the corresponding call to vcos_mutex_quickslow_unlock_quick.
  */
VCOS_INLINE_DECL
void vcos_quickslow_mutex_lock_quick(VCOS_QUICKSLOW_MUTEX_T *m);

/** Release the mutex ("quick" mode).
  */
VCOS_INLINE_DECL
void vcos_quickslow_mutex_unlock_quick(VCOS_QUICKSLOW_MUTEX_T *m);


#ifdef __cplusplus
}
#endif
#endif