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#ifndef AWS_COMMON_ZERO_H 
#define AWS_COMMON_ZERO_H 
 
/** 
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. 
 * SPDX-License-Identifier: Apache-2.0. 
 */ 
 
#include <aws/common/stdbool.h> 
#include <aws/common/stdint.h> 
 
#include <string.h> 
 
AWS_EXTERN_C_BEGIN 
 
/** 
 * Set each byte in the struct to zero. 
 */ 
#define AWS_ZERO_STRUCT(object)                                                                                        \ 
    do {                                                                                                               \ 
        memset(&(object), 0, sizeof(object));                                                                          \ 
    } while (0) 
 
/** 
 * Set each byte in the array to zero. 
 * Does not work with arrays of unknown bound. 
 */ 
#define AWS_ZERO_ARRAY(array) memset((void *)(array), 0, sizeof(array)) 
 
/** 
 * Returns whether each byte in the object is zero. 
 */ 
#ifdef CBMC 
/* clang-format off */ 
#    define AWS_IS_ZEROED(object)                                                                                      \ 
        __CPROVER_forall {                                                                                             \ 
            int i;                                                                                                     \ 
            (i >= 0 && i < sizeof(object)) ==> ((const uint8_t *)&object)[i] == 0                                      \ 
        } 
/* clang-format on */ 
#else 
#    define AWS_IS_ZEROED(object) aws_is_mem_zeroed(&(object), sizeof(object)) 
#endif 
 
/** 
 * Returns whether each byte is zero. 
 */ 
AWS_STATIC_IMPL 
bool aws_is_mem_zeroed(const void *buf, size_t bufsize); 
 
/** 
 * Securely zeroes a memory buffer. This function will attempt to ensure that 
 * the compiler will not optimize away this zeroing operation. 
 */ 
AWS_COMMON_API 
void aws_secure_zero(void *pBuf, size_t bufsize); 
 
#ifndef AWS_NO_STATIC_IMPL 
#    include <aws/common/zero.inl> 
#endif /* AWS_NO_STATIC_IMPL */ 
 
AWS_EXTERN_C_END 
 
#endif /* AWS_COMMON_ZERO_H */