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/*
	WARNING: This file was generated by dkct.
	Changes you make here will be lost if dkct is run again!
	You should modify the original source and run dkct on it.
	Original source: dk4memrs.ctr
*/

/*
Copyright (C) 2015-2017, Dirk Krause

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above opyright 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 author nor the names of contributors may be used
  to endorse or promote products derived from this software without specific
  prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef DK4MEMRS_H_INCLUDED
/** Avoid multiple inclusions. */
#define DK4MEMRS_H_INCLUDED 1


#line 9 "dk4memrs.ctr"

/**	@file
	Secure memory reset (reset byte buffer
	to 0x00 bytes and read the buffer to prevent compilers
	from optimizing the resetting out).
*/

#ifdef __cplusplus
extern "C" {
#endif

/**	Secure memory reset.
	This function does not just reset the bytes to 0,
	it also reads each byte to check it.
	Reading each byte should prevent the compiler from optimizing
	out.
	This function has significantly lower performance than
	dk4mem_reset(), so use it to clear sensitive memory
	(i.e. used for passwords, keys...) only.

	CRT on Windows: Not used.
	@param	ptr	Start address of memory range.
	@param	sz	Size of memory range in bytes.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if ptr is NULL or sz is 0,
	- DK4_E_BUG<br>
	  if one of the bytes in the buffer is not 0 during check.
*/
int
dk4mem_reset_secure(void *ptr, size_t sz, dk4_er_t *erp);

/**	Secure memory release.
	This function does not just reset the bytes to 0 before releasing
	memory, it also reads each byte to check it.
	Reading each byte should prevent the compiler from optimizing
	out.
	This function has significantly lower performance than
	dk4mem_free(), so use it to clear sensitive memory
	(i.e. used for passwords, keys...) only.

	CRT on Windows: Not used.
	@param	ptr	Start address of memory range.
	@param	sz	Size of memory range in bytes.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.

	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if ptr is NULL or sz is 0,
	- DK4_E_BUG<br>
	  if one of the bytes in the buffer is not 0 during check.
*/
int
dk4mem_free_secure(void *ptr, size_t sz, dk4_er_t *erp);

#ifdef __cplusplus
}
#endif

/**	Release memory securely (sanitize memory before releasing it).
*/
#define	dk4mem_release_secure(ptr,sz,erp) \
do { if (NULL != ptr) { (void)dk4mem_free_secure(ptr,sz,erp); } ptr = NULL; } while (0)



#endif