github.com/phillinzzz/newBsc@v1.1.6/tests/fuzzers/bitutil/compress_fuzz.go (about)

     1  // Copyright 2017 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package bitutil
    18  
    19  import (
    20  	"bytes"
    21  
    22  	"github.com/phillinzzz/newBsc/common/bitutil"
    23  )
    24  
    25  // Fuzz implements a go-fuzz fuzzer method to test various encoding method
    26  // invocations.
    27  func Fuzz(data []byte) int {
    28  	if len(data) == 0 {
    29  		return 0
    30  	}
    31  	if data[0]%2 == 0 {
    32  		return fuzzEncode(data[1:])
    33  	}
    34  	return fuzzDecode(data[1:])
    35  }
    36  
    37  // fuzzEncode implements a go-fuzz fuzzer method to test the bitset encoding and
    38  // decoding algorithm.
    39  func fuzzEncode(data []byte) int {
    40  	proc, _ := bitutil.DecompressBytes(bitutil.CompressBytes(data), len(data))
    41  	if !bytes.Equal(data, proc) {
    42  		panic("content mismatch")
    43  	}
    44  	return 1
    45  }
    46  
    47  // fuzzDecode implements a go-fuzz fuzzer method to test the bit decoding and
    48  // reencoding algorithm.
    49  func fuzzDecode(data []byte) int {
    50  	blob, err := bitutil.DecompressBytes(data, 1024)
    51  	if err != nil {
    52  		return 0
    53  	}
    54  	// re-compress it (it's OK if the re-compressed differs from the
    55  	// original - the first input may not have been compressed at all)
    56  	comp := bitutil.CompressBytes(blob)
    57  	if len(comp) > len(blob) {
    58  		// After compression, it must be smaller or equal
    59  		panic("bad compression")
    60  	}
    61  	// But decompressing it once again should work
    62  	decomp, err := bitutil.DecompressBytes(data, 1024)
    63  	if err != nil {
    64  		panic(err)
    65  	}
    66  	if !bytes.Equal(decomp, blob) {
    67  		panic("content mismatch")
    68  	}
    69  	return 1
    70  }