pebble/src/libutil/hash.c
2025-01-27 11:38:16 -08:00

37 lines
967 B
C

/*
* Copyright 2024 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "util/hash.h"
#include <stdint.h>
// Based on DJB2 Hash
uint32_t hash(const uint8_t *bytes, const uint32_t length) {
uint32_t hash = 5381;
if (length == 0) {
return hash;
}
uint8_t c;
const uint8_t *last_byte = bytes + length;
while (bytes != last_byte) {
c = *bytes;
hash = ((hash << 5) + hash) + c;
bytes++;
}
return hash;
}