github.com/google/syzkaller@v0.0.0-20251211124644-a066d2bc4b02/pkg/hash/hash.go (about)

     1  // Copyright 2016 syzkaller project authors. All rights reserved.
     2  // Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
     3  
     4  package hash
     5  
     6  import (
     7  	"bytes"
     8  	"crypto/sha1"
     9  	"encoding/binary"
    10  	"encoding/hex"
    11  	"fmt"
    12  )
    13  
    14  type Sig [sha1.Size]byte
    15  
    16  func Hash(pieces ...any) Sig {
    17  	h := sha1.New()
    18  	for _, data := range pieces {
    19  		if str, ok := data.(string); ok {
    20  			data = []byte(str)
    21  		}
    22  		if err := binary.Write(h, binary.LittleEndian, data); err != nil {
    23  			panic(err)
    24  		}
    25  	}
    26  	var sig Sig
    27  	copy(sig[:], h.Sum(nil))
    28  	return sig
    29  }
    30  
    31  func String(pieces ...any) string {
    32  	sig := Hash(pieces...)
    33  	return sig.String()
    34  }
    35  
    36  func (sig *Sig) String() string {
    37  	return hex.EncodeToString((*sig)[:])
    38  }
    39  
    40  // Truncate64 returns first 64 bits of the hash as int64.
    41  func (sig *Sig) Truncate64() int64 {
    42  	var v int64
    43  	if err := binary.Read(bytes.NewReader((*sig)[:]), binary.LittleEndian, &v); err != nil {
    44  		panic(fmt.Sprintf("failed convert hash to id: %v", err))
    45  	}
    46  	return v
    47  }