1 /**
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40 /** @file
41  *
42  * @defgroup crc16 CRC16 compute
43  * @{
44  * @ingroup hci_transport
45  *
46  * @brief    This module implements CRC-16-CCITT (polynomial 0x1021) with 0xFFFF initial value.
47  *           The data can be passed in multiple blocks.
48  */
49 
50 #ifndef CRC16_H__
51 #define CRC16_H__
52 
53 #include <stdint.h>
54 
55 #ifdef __cplusplus
56 extern "C"
57 {
58 #endif
59 
60     /**@brief Function for calculating CRC-16 in blocks.
61  *
62  * Feed each consecutive data block into this function, along with the current value of p_crc as
63  * returned by the previous call of this function. The first call of this function should pass NULL
64  * as the initial value of the crc in p_crc.
65  *
66  * @param[in] p_data The input data block for computation.
67  * @param[in] size   The size of the input data block in bytes.
68  * @param[in] p_crc  The previous calculated CRC-16 value or NULL if first call.
69  *
70  * @return The updated CRC-16 value, based on the input supplied.
71  */
72     uint16_t util_crc16_compute(uint8_t const *p_data, uint32_t size, uint16_t const *p_crc);
73 
74     /**@brief Function for calculating CRC-16-CCITT in blocks.
75  *
76  * Feed each consecutive data block into this function, along with the current value of p_crc as
77  * returned by the previous call of this function. The first call of this function should pass NULL
78  * as the initial value of the crc in p_crc.
79  *
80  * @param[in] p_data The input data block for computation.
81  * @param[in] size   The size of the input data block in bytes.
82  * @param[in] p_crc  The previous calculated CRC-16 value or NULL if first call.
83  *
84  * @return The updated CRC-16-CCITT value, based on the input supplied.
85  */
86     uint16_t util_crc16_ccitt(uint8_t const *p_data, uint32_t size, uint16_t const *p_crc);
87 
88 #ifdef __cplusplus
89 }
90 #endif
91 
92 #endif // CRC16_H__
93 
94 /** @} */
95