mirror of
https://github.com/Keychron/qmk_firmware.git
synced 2024-11-23 08:56:47 +06:00
01ecf332ff
* Initial import of wear-leveling algorithm. * Alignment. * Docs tweaks. * Lock/unlock. * Update quantum/wear_leveling/wear_leveling_internal.h Co-authored-by: Stefan Kerkmann <karlk90@pm.me> * More tests, fix issue with consolidation when unlocked. * More tests. * Review comments. * Add plumbing for FNV1a. * Another test checking that checksum mismatch clears the cache. * Check that the write log still gets played back. Co-authored-by: Stefan Kerkmann <karlk90@pm.me>
313 lines
8.6 KiB
C
313 lines
8.6 KiB
C
/*
|
|
* hash_64 - 64 bit Fowler/Noll/Vo-0 hash code
|
|
*
|
|
* @(#) $Revision: 5.1 $
|
|
* @(#) $Id: hash_64.c,v 5.1 2009/06/30 09:01:38 chongo Exp $
|
|
* @(#) $Source: /usr/local/src/cmd/fnv/RCS/hash_64.c,v $
|
|
*
|
|
***
|
|
*
|
|
* Fowler/Noll/Vo hash
|
|
*
|
|
* The basis of this hash algorithm was taken from an idea sent
|
|
* as reviewer comments to the IEEE POSIX P1003.2 committee by:
|
|
*
|
|
* Phong Vo (http://www.research.att.com/info/kpv/)
|
|
* Glenn Fowler (http://www.research.att.com/~gsf/)
|
|
*
|
|
* In a subsequent ballot round:
|
|
*
|
|
* Landon Curt Noll (http://www.isthe.com/chongo/)
|
|
*
|
|
* improved on their algorithm. Some people tried this hash
|
|
* and found that it worked rather well. In an EMail message
|
|
* to Landon, they named it the ``Fowler/Noll/Vo'' or FNV hash.
|
|
*
|
|
* FNV hashes are designed to be fast while maintaining a low
|
|
* collision rate. The FNV speed allows one to quickly hash lots
|
|
* of data while maintaining a reasonable collision rate. See:
|
|
*
|
|
* http://www.isthe.com/chongo/tech/comp/fnv/index.html
|
|
*
|
|
* for more details as well as other forms of the FNV hash.
|
|
*
|
|
***
|
|
*
|
|
* NOTE: The FNV-0 historic hash is not recommended. One should use
|
|
* the FNV-1 hash instead.
|
|
*
|
|
* To use the 64 bit FNV-0 historic hash, pass FNV0_64_INIT as the
|
|
* Fnv64_t hashval argument to fnv_64_buf() or fnv_64_str().
|
|
*
|
|
* To use the recommended 64 bit FNV-1 hash, pass FNV1_64_INIT as the
|
|
* Fnv64_t hashval argument to fnv_64_buf() or fnv_64_str().
|
|
*
|
|
***
|
|
*
|
|
* Please do not copyright this code. This code is in the public domain.
|
|
*
|
|
* LANDON CURT NOLL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
|
|
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO
|
|
* EVENT SHALL LANDON CURT NOLL BE LIABLE FOR ANY SPECIAL, INDIRECT OR
|
|
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
|
|
* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
|
|
* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
|
|
* PERFORMANCE OF THIS SOFTWARE.
|
|
*
|
|
* By:
|
|
* chongo <Landon Curt Noll> /\oo/\
|
|
* http://www.isthe.com/chongo/
|
|
*
|
|
* Share and Enjoy! :-)
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include "fnv.h"
|
|
|
|
|
|
/*
|
|
* FNV-0 defines the initial basis to be zero
|
|
*/
|
|
#if !defined(HAVE_64BIT_LONG_LONG)
|
|
const Fnv64_t fnv0_64_init = { 0UL, 0UL };
|
|
#endif /* ! HAVE_64BIT_LONG_LONG */
|
|
|
|
|
|
/*
|
|
* FNV-1 defines the initial basis to be non-zero
|
|
*/
|
|
#if !defined(HAVE_64BIT_LONG_LONG)
|
|
const Fnv64_t fnv1_64_init = { 0x84222325UL, 0xcbf29ce4UL };
|
|
#endif /* ! HAVE_64BIT_LONG_LONG */
|
|
|
|
|
|
/*
|
|
* 64 bit magic FNV-0 and FNV-1 prime
|
|
*/
|
|
#if defined(HAVE_64BIT_LONG_LONG)
|
|
#define FNV_64_PRIME ((Fnv64_t)0x100000001b3ULL)
|
|
#else /* HAVE_64BIT_LONG_LONG */
|
|
#define FNV_64_PRIME_LOW ((unsigned long)0x1b3) /* lower bits of FNV prime */
|
|
#define FNV_64_PRIME_SHIFT (8) /* top FNV prime shift above 2^32 */
|
|
#endif /* HAVE_64BIT_LONG_LONG */
|
|
|
|
|
|
/*
|
|
* fnv_64_buf - perform a 64 bit Fowler/Noll/Vo hash on a buffer
|
|
*
|
|
* input:
|
|
* buf - start of buffer to hash
|
|
* len - length of buffer in octets
|
|
* hval - previous hash value or 0 if first call
|
|
*
|
|
* returns:
|
|
* 64 bit hash as a static hash type
|
|
*
|
|
* NOTE: To use the 64 bit FNV-0 historic hash, use FNV0_64_INIT as the hval
|
|
* argument on the first call to either fnv_64_buf() or fnv_64_str().
|
|
*
|
|
* NOTE: To use the recommended 64 bit FNV-1 hash, use FNV1_64_INIT as the hval
|
|
* argument on the first call to either fnv_64_buf() or fnv_64_str().
|
|
*/
|
|
Fnv64_t
|
|
fnv_64_buf(void *buf, size_t len, Fnv64_t hval)
|
|
{
|
|
unsigned char *bp = (unsigned char *)buf; /* start of buffer */
|
|
unsigned char *be = bp + len; /* beyond end of buffer */
|
|
|
|
#if defined(HAVE_64BIT_LONG_LONG)
|
|
|
|
/*
|
|
* FNV-1 hash each octet of the buffer
|
|
*/
|
|
while (bp < be) {
|
|
|
|
/* multiply by the 64 bit FNV magic prime mod 2^64 */
|
|
#if defined(NO_FNV_GCC_OPTIMIZATION)
|
|
hval *= FNV_64_PRIME;
|
|
#else /* NO_FNV_GCC_OPTIMIZATION */
|
|
hval += (hval << 1) + (hval << 4) + (hval << 5) +
|
|
(hval << 7) + (hval << 8) + (hval << 40);
|
|
#endif /* NO_FNV_GCC_OPTIMIZATION */
|
|
|
|
/* xor the bottom with the current octet */
|
|
hval ^= (Fnv64_t)*bp++;
|
|
}
|
|
|
|
#else /* HAVE_64BIT_LONG_LONG */
|
|
|
|
unsigned long val[4]; /* hash value in base 2^16 */
|
|
unsigned long tmp[4]; /* tmp 64 bit value */
|
|
|
|
/*
|
|
* Convert Fnv64_t hval into a base 2^16 array
|
|
*/
|
|
val[0] = hval.w32[0];
|
|
val[1] = (val[0] >> 16);
|
|
val[0] &= 0xffff;
|
|
val[2] = hval.w32[1];
|
|
val[3] = (val[2] >> 16);
|
|
val[2] &= 0xffff;
|
|
|
|
/*
|
|
* FNV-1 hash each octet of the buffer
|
|
*/
|
|
while (bp < be) {
|
|
|
|
/*
|
|
* multiply by the 64 bit FNV magic prime mod 2^64
|
|
*
|
|
* Using 0x100000001b3 we have the following digits base 2^16:
|
|
*
|
|
* 0x0 0x100 0x0 0x1b3
|
|
*
|
|
* which is the same as:
|
|
*
|
|
* 0x0 1<<FNV_64_PRIME_SHIFT 0x0 FNV_64_PRIME_LOW
|
|
*/
|
|
/* multiply by the lowest order digit base 2^16 */
|
|
tmp[0] = val[0] * FNV_64_PRIME_LOW;
|
|
tmp[1] = val[1] * FNV_64_PRIME_LOW;
|
|
tmp[2] = val[2] * FNV_64_PRIME_LOW;
|
|
tmp[3] = val[3] * FNV_64_PRIME_LOW;
|
|
/* multiply by the other non-zero digit */
|
|
tmp[2] += val[0] << FNV_64_PRIME_SHIFT; /* tmp[2] += val[0] * 0x100 */
|
|
tmp[3] += val[1] << FNV_64_PRIME_SHIFT; /* tmp[3] += val[1] * 0x100 */
|
|
/* propagate carries */
|
|
tmp[1] += (tmp[0] >> 16);
|
|
val[0] = tmp[0] & 0xffff;
|
|
tmp[2] += (tmp[1] >> 16);
|
|
val[1] = tmp[1] & 0xffff;
|
|
val[3] = tmp[3] + (tmp[2] >> 16);
|
|
val[2] = tmp[2] & 0xffff;
|
|
/*
|
|
* Doing a val[3] &= 0xffff; is not really needed since it simply
|
|
* removes multiples of 2^64. We can discard these excess bits
|
|
* outside of the loop when we convert to Fnv64_t.
|
|
*/
|
|
|
|
/* xor the bottom with the current octet */
|
|
val[0] ^= (unsigned long)*bp++;
|
|
}
|
|
|
|
/*
|
|
* Convert base 2^16 array back into an Fnv64_t
|
|
*/
|
|
hval.w32[1] = ((val[3]<<16) | val[2]);
|
|
hval.w32[0] = ((val[1]<<16) | val[0]);
|
|
|
|
#endif /* HAVE_64BIT_LONG_LONG */
|
|
|
|
/* return our new hash value */
|
|
return hval;
|
|
}
|
|
|
|
|
|
/*
|
|
* fnv_64_str - perform a 64 bit Fowler/Noll/Vo hash on a buffer
|
|
*
|
|
* input:
|
|
* buf - start of buffer to hash
|
|
* hval - previous hash value or 0 if first call
|
|
*
|
|
* returns:
|
|
* 64 bit hash as a static hash type
|
|
*
|
|
* NOTE: To use the 64 bit FNV-0 historic hash, use FNV0_64_INIT as the hval
|
|
* argument on the first call to either fnv_64_buf() or fnv_64_str().
|
|
*
|
|
* NOTE: To use the recommended 64 bit FNV-1 hash, use FNV1_64_INIT as the hval
|
|
* argument on the first call to either fnv_64_buf() or fnv_64_str().
|
|
*/
|
|
Fnv64_t
|
|
fnv_64_str(char *str, Fnv64_t hval)
|
|
{
|
|
unsigned char *s = (unsigned char *)str; /* unsigned string */
|
|
|
|
#if defined(HAVE_64BIT_LONG_LONG)
|
|
|
|
/*
|
|
* FNV-1 hash each octet of the string
|
|
*/
|
|
while (*s) {
|
|
|
|
/* multiply by the 64 bit FNV magic prime mod 2^64 */
|
|
#if defined(NO_FNV_GCC_OPTIMIZATION)
|
|
hval *= FNV_64_PRIME;
|
|
#else /* NO_FNV_GCC_OPTIMIZATION */
|
|
hval += (hval << 1) + (hval << 4) + (hval << 5) +
|
|
(hval << 7) + (hval << 8) + (hval << 40);
|
|
#endif /* NO_FNV_GCC_OPTIMIZATION */
|
|
|
|
/* xor the bottom with the current octet */
|
|
hval ^= (Fnv64_t)*s++;
|
|
}
|
|
|
|
#else /* !HAVE_64BIT_LONG_LONG */
|
|
|
|
unsigned long val[4]; /* hash value in base 2^16 */
|
|
unsigned long tmp[4]; /* tmp 64 bit value */
|
|
|
|
/*
|
|
* Convert Fnv64_t hval into a base 2^16 array
|
|
*/
|
|
val[0] = hval.w32[0];
|
|
val[1] = (val[0] >> 16);
|
|
val[0] &= 0xffff;
|
|
val[2] = hval.w32[1];
|
|
val[3] = (val[2] >> 16);
|
|
val[2] &= 0xffff;
|
|
|
|
/*
|
|
* FNV-1 hash each octet of the string
|
|
*/
|
|
while (*s) {
|
|
|
|
/*
|
|
* multiply by the 64 bit FNV magic prime mod 2^64
|
|
*
|
|
* Using 1099511628211, we have the following digits base 2^16:
|
|
*
|
|
* 0x0 0x100 0x0 0x1b3
|
|
*
|
|
* which is the same as:
|
|
*
|
|
* 0x0 1<<FNV_64_PRIME_SHIFT 0x0 FNV_64_PRIME_LOW
|
|
*/
|
|
/* multiply by the lowest order digit base 2^16 */
|
|
tmp[0] = val[0] * FNV_64_PRIME_LOW;
|
|
tmp[1] = val[1] * FNV_64_PRIME_LOW;
|
|
tmp[2] = val[2] * FNV_64_PRIME_LOW;
|
|
tmp[3] = val[3] * FNV_64_PRIME_LOW;
|
|
/* multiply by the other non-zero digit */
|
|
tmp[2] += val[0] << FNV_64_PRIME_SHIFT; /* tmp[2] += val[0] * 0x100 */
|
|
tmp[3] += val[1] << FNV_64_PRIME_SHIFT; /* tmp[3] += val[1] * 0x100 */
|
|
/* propagate carries */
|
|
tmp[1] += (tmp[0] >> 16);
|
|
val[0] = tmp[0] & 0xffff;
|
|
tmp[2] += (tmp[1] >> 16);
|
|
val[1] = tmp[1] & 0xffff;
|
|
val[3] = tmp[3] + (tmp[2] >> 16);
|
|
val[2] = tmp[2] & 0xffff;
|
|
/*
|
|
* Doing a val[3] &= 0xffff; is not really needed since it simply
|
|
* removes multiples of 2^64. We can discard these excess bits
|
|
* outside of the loop when we convert to Fnv64_t.
|
|
*/
|
|
|
|
/* xor the bottom with the current octet */
|
|
val[0] ^= (unsigned long)(*s++);
|
|
}
|
|
|
|
/*
|
|
* Convert base 2^16 array back into an Fnv64_t
|
|
*/
|
|
hval.w32[1] = ((val[3]<<16) | val[2]);
|
|
hval.w32[0] = ((val[1]<<16) | val[0]);
|
|
|
|
#endif /* !HAVE_64BIT_LONG_LONG */
|
|
|
|
/* return our new hash value */
|
|
return hval;
|
|
}
|