string.c (mrb_byte_hash): separate byte hashing functions.
@@ -1665,22 +1665,19 @@ mrb_str_substr(mrb_state *mrb, mrb_value str, mrb_int beg, mrb_int len)
/*
* 32 bit magic FNV-0 and FNV-1 prime
- */
+b */
#define FNV_32_PRIME ((uint32_t)0x01000193)
#define FNV1_32_INIT ((uint32_t)0x811c9dc5)
uint32_t
-mrb_str_hash(mrb_state *mrb, mrb_value str)
+mrb_byte_hash_step(const uint8_t *s, mrb_int len, uint32_t hval)
{
- struct RString *s = mrb_str_ptr(str);
- const unsigned char *bp = (unsigned char*)RSTR_PTR(s); /* start of buffer */
- const unsigned char *be = bp + RSTR_LEN(s); /* beyond end of buffer */
- uint32_t hval = FNV1_32_INIT;
+ const uint8_t *send = s + len;
/*
* FNV-1 hash each octet in the buffer
*/
- while (bp < be) {
+ while (s < send) {
/* multiply by the 32 bit FNV magic prime mod 2^32 */
#if defined(NO_FNV_GCC_OPTIMIZATION)
hval *= FNV_32_PRIME;
@@ -1689,13 +1686,26 @@ mrb_str_hash(mrb_state *mrb, mrb_value str)
#endif
/* xor the bottom with the current octet */
- hval ^= (uint32_t)*bp++;
+ hval ^= (uint32_t)*s++;
}
/* return our new hash value */
return hval;
}
+uint32_t
+mrb_byte_hash(const uint8_t *s, mrb_int len)
+{
+ return mrb_byte_hash_step(s, len, FNV1_32_INIT);
+}
+
+uint32_t
+mrb_str_hash(mrb_state *mrb, mrb_value str)
+{
+ struct RString *s = mrb_str_ptr(str);
+ return mrb_byte_hash((uint8_t*)RSTR_PTR(s), RSTR_LEN(s));
+}
+
/* 15.2.10.5.20 */
/*
* call-seq:
