# verify should fail on a missing ziphash. tidy should restore it.
rm $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.1.0.ziphash
! go mod verify
stderr '^rsc.io/quote v1.1.0: missing ziphash: open '$GOPATH'[/\\]pkg[/\\]mod[/\\]cache[/\\]download[/\\]rsc.io[/\\]quote[/\\]@v[/\\]v1.1.0.ziphash'
go mod tidy
exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.1.0.ziphash
go mod verify

	// Do the file I/O before acquiring the go.sum lock.
	ziphash, err := CachePath(ctx, mod, "ziphash")
	if err != nil {
		base.Fatalf("verifying %v", module.VersionError(mod, err))
	}
	data, err := lockedfile.Read(ziphash)
	if err != nil {
		base.Fatalf("verifying %v", module.VersionError(mod, err))
	}
	data = bytes.TrimSpace(data)
	if !isValidSum(data) {
		// Recreate ziphash file from zip file and use that to check the mod sum.

go get use
cmp go.sum go.sum.tidy
go build -n use

# If we delete the hash *and* the ziphash file, we should see the same behavior.
cp go.sum.bug go.sum
rm $WORK/gopath/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.2.ziphash
! go build -n use
stderr '^use.go:3:8: missing go.sum entry for module providing package rsc.io/quote \(imported by use\); to add:\n\tgo get use$'
go get use

			h := sha256.New()
			f, err := os.Open(zipPath)
			if err != nil {
				t.Errorf("%s: %v", test.m, err)
			}
			defer f.Close()
			if _, err := io.Copy(h, f); err != nil {
				t.Errorf("%s: %v", test.m, err)
			}
			zipHash := hex.EncodeToString(h.Sum(nil))
			if zipHash != test.wantFileHash {
				if *updateTestData {
					t.Logf("%s: updating zip file hash to %s", test.m, zipHash)
					test.wantFileHash = zipHash

			return nil
		}
		errs = append(errs, fmt.Errorf("%s %s: missing ziphash: %v", mod.Path, mod.Version, err))
		return errs
	}
	h := string(bytes.TrimSpace(data))

	if zipErr != nil && errors.Is(zipErr, fs.ErrNotExist) {
		// ok
	} else {
		hZ, err := dirhash.HashZip(zip, dirhash.DefaultHash)
		if err != nil {
			errs = append(errs, fmt.Errorf("%s %s: %v", mod.Path, mod.Version, err))

	} else if !os.IsNotExist(err) {
		return dir, err
	}

	// Check if a .ziphash file exists. It should be created before the
	// zip is extracted, but if it was deleted (by another program?), we need
	// to re-calculate it. Note that checkMod will repopulate the ziphash
	// file if it doesn't exist, but if the module is excluded by checks

import java.util.Set;

public class ZipHasher implements RegularFileSnapshotContextHasher, ConfigurableNormalizer {

    private static final Set<String> KNOWN_ZIP_EXTENSIONS = ImmutableSet.of("zip", "jar", "war", "rar", "ear", "apk", "aar", "klib");
    private static final Logger LOGGER = LoggerFactory.getLogger(ZipHasher.class);
    private static final HashCode EMPTY_HASH_MARKER = Hashing.signature(ZipHasher.class);

// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package maphash provides hash functions on byte sequences.
// These hash functions are intended to be used to implement hash tables or
// other data structures that need to map arbitrary strings or byte
// sequences to a uniform distribution on unsigned 64-bit integers.

      for (int j = 0; j < i; ++j) {
        msg[j] = (byte) j;
      }
      assertSip(msg, EXPECTED[i]);
    }
  }

  // This test data comes from "SipHash: a fast short-input PRF", "Appendix A: Test values".
  // It can be downloaded here: https://131002.net/siphash/siphash.pdf
  public void test15ByteStringFromSipHashPaper() {
    byte[] message =
        new byte[] {

 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

/*
 * SipHash-c-d was designed by Jean-Philippe Aumasson and Daniel J. Bernstein and is described in
 * "SipHash: a fast short-input PRF" (available at https://131002.net/siphash/siphash.pdf).
 */

package com.google.common.hash;

import static com.google.common.base.Preconditions.checkArgument;