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Document the properties of the CRC functions

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This commit is contained in:
Jef Driesen 2023-02-10 21:12:05 +01:00
parent 00033e4af0
commit 27b471e76b
1 changed files with 25 additions and 0 deletions
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25
src/checksum.c
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@ -68,6 +68,11 @@ checksum_xor_uint8 (const unsigned char data[], unsigned int size, unsigned char
}
/*
* Polynomial: 0x1021
* RefIn: False
* RefOut: False
*/
unsigned short
checksum_crc16_ccitt (const unsigned char data[], unsigned int size, unsigned short init, unsigned short xorout)
{
@ -114,6 +119,11 @@ checksum_crc16_ccitt (const unsigned char data[], unsigned int size, unsigned sh
}
/*
* Polynomial: 0x1021
* RefIn: True
* RefOut: True
*/
unsigned short
checksum_crc16r_ccitt (const unsigned char data[], unsigned int size, unsigned short init, unsigned short xorout)
{
@ -160,6 +170,13 @@ checksum_crc16r_ccitt (const unsigned char data[], unsigned int size, unsigned s
}
/*
* Polynomial: 0x04C11DB7
* Init: 0xffffffff
* XorOut: 0xffffffff
* RefIn: True
* RefOut: True
*/
unsigned int
checksum_crc32r (const unsigned char data[], unsigned int size)
{
@ -205,6 +222,14 @@ checksum_crc32r (const unsigned char data[], unsigned int size)
return crc ^ 0xffffffff;
}
/*
* Polynomial: 0x04C11DB7
* Init: 0xffffffff
* XorOut: 0xffffffff
* RefIn: False
* RefOut: False
*/
unsigned int
checksum_crc32 (const unsigned char data[], unsigned int size)
{