github.com/wangyougui/gf/v2@v2.6.5/encoding/ghash/ghash_rs.go (about)

     1  // Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
     2  //
     3  // This Source Code Form is subject to the terms of the MIT License.
     4  // If a copy of the MIT was not distributed with this file,
     5  // You can obtain one at https://github.com/wangyougui/gf.
     6  
     7  package ghash
     8  
     9  // RS implements the classic RS hash algorithm for 32 bits.
    10  func RS(str []byte) uint32 {
    11  	var (
    12  		b    uint32 = 378551
    13  		a    uint32 = 63689
    14  		hash uint32 = 0
    15  	)
    16  	for i := 0; i < len(str); i++ {
    17  		hash = hash*a + uint32(str[i])
    18  		a *= b
    19  	}
    20  	return hash
    21  }
    22  
    23  // RS64 implements the classic RS hash algorithm for 64 bits.
    24  func RS64(str []byte) uint64 {
    25  	var (
    26  		b    uint64 = 378551
    27  		a    uint64 = 63689
    28  		hash uint64 = 0
    29  	)
    30  	for i := 0; i < len(str); i++ {
    31  		hash = hash*a + uint64(str[i])
    32  		a *= b
    33  	}
    34  	return hash
    35  }