dedup

commit e8031b23797e666b43f96906372d97e2da4f4d0a
parent 51e30cc320f67d76423856e7f0fc790431f9cf5f
Author: sin <sin@2f30.org>
Date:   Fri, 22 Feb 2019 11:20:51 +0000

Simplify hash a bit

Diffstat:
M
hash.c
 | 
15
++++++---------

1 file changed, 6 insertions(+), 9 deletions(-)
diff --git a/hash.c b/hash.c
@@ -49,22 +49,19 @@ static uint32_t buz[] = {
 
 /* Buzhash: https://en.wikipedia.org/wiki/Rolling_hash#Cyclic_polynomial */
 uint32_t
-buzh_init(uint8_t *buf, size_t size)
+buzh_init(uint8_t *buf, size_t winsize)
 {
-	size_t i;
 	uint32_t fp;
+	size_t i;
 
-	if (!size)
-		return 0;
-
-	for (i = size - 1, fp = 0; i > 0; i--, buf++)
-		fp ^= ROTL(buz[*buf], i % 32);
+	for (i = 1, fp = 0; i < winsize; i++, buf++)
+		fp ^= ROTL(buz[*buf], (winsize - i) % 32);
 
 	return fp ^ buz[*buf];
 }
 
 uint32_t
-buzh_update(uint32_t fp, uint8_t in, uint8_t out, size_t size)
+buzh_update(uint32_t fp, uint8_t in, uint8_t out, size_t winsize)
 {
-	return ROTL(fp, 1) ^ ROTL(buz[out], size % 32) ^ buz[in];
+	return ROTL(fp, 1) ^ ROTL(buz[out], winsize % 32) ^ buz[in];
 }