X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=crc%2Ffnv.c;h=4cd06501fd2e1b92bed2bb8d5e9eff0a85c74ddc;hp=04c0560c9f421bea6796b1f3aef680bc5eb80827;hb=855f03627f2bce6a7f725fe6cc92e7ebe8d39deb;hpb=41177ed32fe815545061f7d10ce13559f1e9eb98

diff --git a/crc/fnv.c b/crc/fnv.c
index 04c0560c..4cd06501 100644
--- a/crc/fnv.c
+++ b/crc/fnv.c
@@ -2,14 +2,32 @@
 
 #define FNV_PRIME	0x100000001b3ULL
 
+/*
+ * 64-bit fnv, but don't require 64-bit multiples of data. Use bytes
+ * for the last unaligned chunk.
+ */
 uint64_t fnv(const void *buf, uint32_t len, uint64_t hval)
 {
 	const uint64_t *ptr = buf;
-	const uint64_t *end = (void *) buf + len;
 
-	while (ptr < end) {
+	while (len) {
 		hval *= FNV_PRIME;
-		hval ^= (uint64_t) *ptr++;
+		if (len >= sizeof(uint64_t)) {
+			hval ^= (uint64_t) *ptr++;
+			len -= sizeof(uint64_t);
+			continue;
+		} else {
+			const uint8_t *ptr8 = (const uint8_t *) ptr;
+			uint64_t val = 0;
+			int i;
+
+			for (i = 0; i < len; i++) {
+				val <<= 8;
+				val |= (uint8_t) *ptr8++;
+			}
+			hval ^= val;
+			break;
+		}
 	}
 
 	return hval;