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-rw-r--r--src/compress/gzip/gunzip.go287
-rw-r--r--src/compress/gzip/gunzip_test.go410
-rw-r--r--src/compress/gzip/gzip.go272
-rw-r--r--src/compress/gzip/gzip_test.go231
-rw-r--r--src/compress/gzip/testdata/issue6550.gzbin0 -> 65536 bytes
5 files changed, 1200 insertions, 0 deletions
diff --git a/src/compress/gzip/gunzip.go b/src/compress/gzip/gunzip.go
new file mode 100644
index 000000000..72ee55c4f
--- /dev/null
+++ b/src/compress/gzip/gunzip.go
@@ -0,0 +1,287 @@
+// Copyright 2009 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 gzip implements reading and writing of gzip format compressed files,
+// as specified in RFC 1952.
+package gzip
+
+import (
+ "bufio"
+ "compress/flate"
+ "errors"
+ "hash"
+ "hash/crc32"
+ "io"
+ "time"
+)
+
+const (
+ gzipID1 = 0x1f
+ gzipID2 = 0x8b
+ gzipDeflate = 8
+ flagText = 1 << 0
+ flagHdrCrc = 1 << 1
+ flagExtra = 1 << 2
+ flagName = 1 << 3
+ flagComment = 1 << 4
+)
+
+func makeReader(r io.Reader) flate.Reader {
+ if rr, ok := r.(flate.Reader); ok {
+ return rr
+ }
+ return bufio.NewReader(r)
+}
+
+var (
+ // ErrChecksum is returned when reading GZIP data that has an invalid checksum.
+ ErrChecksum = errors.New("gzip: invalid checksum")
+ // ErrHeader is returned when reading GZIP data that has an invalid header.
+ ErrHeader = errors.New("gzip: invalid header")
+)
+
+// The gzip file stores a header giving metadata about the compressed file.
+// That header is exposed as the fields of the Writer and Reader structs.
+type Header struct {
+ Comment string // comment
+ Extra []byte // "extra data"
+ ModTime time.Time // modification time
+ Name string // file name
+ OS byte // operating system type
+}
+
+// A Reader is an io.Reader that can be read to retrieve
+// uncompressed data from a gzip-format compressed file.
+//
+// In general, a gzip file can be a concatenation of gzip files,
+// each with its own header. Reads from the Reader
+// return the concatenation of the uncompressed data of each.
+// Only the first header is recorded in the Reader fields.
+//
+// Gzip files store a length and checksum of the uncompressed data.
+// The Reader will return a ErrChecksum when Read
+// reaches the end of the uncompressed data if it does not
+// have the expected length or checksum. Clients should treat data
+// returned by Read as tentative until they receive the io.EOF
+// marking the end of the data.
+type Reader struct {
+ Header
+ r flate.Reader
+ decompressor io.ReadCloser
+ digest hash.Hash32
+ size uint32
+ flg byte
+ buf [512]byte
+ err error
+ multistream bool
+}
+
+// NewReader creates a new Reader reading the given reader.
+// If r does not also implement io.ByteReader,
+// the decompressor may read more data than necessary from r.
+// It is the caller's responsibility to call Close on the Reader when done.
+func NewReader(r io.Reader) (*Reader, error) {
+ z := new(Reader)
+ z.r = makeReader(r)
+ z.multistream = true
+ z.digest = crc32.NewIEEE()
+ if err := z.readHeader(true); err != nil {
+ return nil, err
+ }
+ return z, nil
+}
+
+// Reset discards the Reader z's state and makes it equivalent to the
+// result of its original state from NewReader, but reading from r instead.
+// This permits reusing a Reader rather than allocating a new one.
+func (z *Reader) Reset(r io.Reader) error {
+ z.r = makeReader(r)
+ if z.digest == nil {
+ z.digest = crc32.NewIEEE()
+ } else {
+ z.digest.Reset()
+ }
+ z.size = 0
+ z.err = nil
+ z.multistream = true
+ return z.readHeader(true)
+}
+
+// Multistream controls whether the reader supports multistream files.
+//
+// If enabled (the default), the Reader expects the input to be a sequence
+// of individually gzipped data streams, each with its own header and
+// trailer, ending at EOF. The effect is that the concatenation of a sequence
+// of gzipped files is treated as equivalent to the gzip of the concatenation
+// of the sequence. This is standard behavior for gzip readers.
+//
+// Calling Multistream(false) disables this behavior; disabling the behavior
+// can be useful when reading file formats that distinguish individual gzip
+// data streams or mix gzip data streams with other data streams.
+// In this mode, when the Reader reaches the end of the data stream,
+// Read returns io.EOF. If the underlying reader implements io.ByteReader,
+// it will be left positioned just after the gzip stream.
+// To start the next stream, call z.Reset(r) followed by z.Multistream(false).
+// If there is no next stream, z.Reset(r) will return io.EOF.
+func (z *Reader) Multistream(ok bool) {
+ z.multistream = ok
+}
+
+// GZIP (RFC 1952) is little-endian, unlike ZLIB (RFC 1950).
+func get4(p []byte) uint32 {
+ return uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 | uint32(p[3])<<24
+}
+
+func (z *Reader) readString() (string, error) {
+ var err error
+ needconv := false
+ for i := 0; ; i++ {
+ if i >= len(z.buf) {
+ return "", ErrHeader
+ }
+ z.buf[i], err = z.r.ReadByte()
+ if err != nil {
+ return "", err
+ }
+ if z.buf[i] > 0x7f {
+ needconv = true
+ }
+ if z.buf[i] == 0 {
+ // GZIP (RFC 1952) specifies that strings are NUL-terminated ISO 8859-1 (Latin-1).
+ if needconv {
+ s := make([]rune, 0, i)
+ for _, v := range z.buf[0:i] {
+ s = append(s, rune(v))
+ }
+ return string(s), nil
+ }
+ return string(z.buf[0:i]), nil
+ }
+ }
+}
+
+func (z *Reader) read2() (uint32, error) {
+ _, err := io.ReadFull(z.r, z.buf[0:2])
+ if err != nil {
+ return 0, err
+ }
+ return uint32(z.buf[0]) | uint32(z.buf[1])<<8, nil
+}
+
+func (z *Reader) readHeader(save bool) error {
+ _, err := io.ReadFull(z.r, z.buf[0:10])
+ if err != nil {
+ return err
+ }
+ if z.buf[0] != gzipID1 || z.buf[1] != gzipID2 || z.buf[2] != gzipDeflate {
+ return ErrHeader
+ }
+ z.flg = z.buf[3]
+ if save {
+ z.ModTime = time.Unix(int64(get4(z.buf[4:8])), 0)
+ // z.buf[8] is xfl, ignored
+ z.OS = z.buf[9]
+ }
+ z.digest.Reset()
+ z.digest.Write(z.buf[0:10])
+
+ if z.flg&flagExtra != 0 {
+ n, err := z.read2()
+ if err != nil {
+ return err
+ }
+ data := make([]byte, n)
+ if _, err = io.ReadFull(z.r, data); err != nil {
+ return err
+ }
+ if save {
+ z.Extra = data
+ }
+ }
+
+ var s string
+ if z.flg&flagName != 0 {
+ if s, err = z.readString(); err != nil {
+ return err
+ }
+ if save {
+ z.Name = s
+ }
+ }
+
+ if z.flg&flagComment != 0 {
+ if s, err = z.readString(); err != nil {
+ return err
+ }
+ if save {
+ z.Comment = s
+ }
+ }
+
+ if z.flg&flagHdrCrc != 0 {
+ n, err := z.read2()
+ if err != nil {
+ return err
+ }
+ sum := z.digest.Sum32() & 0xFFFF
+ if n != sum {
+ return ErrHeader
+ }
+ }
+
+ z.digest.Reset()
+ if z.decompressor == nil {
+ z.decompressor = flate.NewReader(z.r)
+ } else {
+ z.decompressor.(flate.Resetter).Reset(z.r, nil)
+ }
+ return nil
+}
+
+func (z *Reader) Read(p []byte) (n int, err error) {
+ if z.err != nil {
+ return 0, z.err
+ }
+ if len(p) == 0 {
+ return 0, nil
+ }
+
+ n, err = z.decompressor.Read(p)
+ z.digest.Write(p[0:n])
+ z.size += uint32(n)
+ if n != 0 || err != io.EOF {
+ z.err = err
+ return
+ }
+
+ // Finished file; check checksum + size.
+ if _, err := io.ReadFull(z.r, z.buf[0:8]); err != nil {
+ z.err = err
+ return 0, err
+ }
+ crc32, isize := get4(z.buf[0:4]), get4(z.buf[4:8])
+ sum := z.digest.Sum32()
+ if sum != crc32 || isize != z.size {
+ z.err = ErrChecksum
+ return 0, z.err
+ }
+
+ // File is ok; is there another?
+ if !z.multistream {
+ return 0, io.EOF
+ }
+
+ if err = z.readHeader(false); err != nil {
+ z.err = err
+ return
+ }
+
+ // Yes. Reset and read from it.
+ z.digest.Reset()
+ z.size = 0
+ return z.Read(p)
+}
+
+// Close closes the Reader. It does not close the underlying io.Reader.
+func (z *Reader) Close() error { return z.decompressor.Close() }
diff --git a/src/compress/gzip/gunzip_test.go b/src/compress/gzip/gunzip_test.go
new file mode 100644
index 000000000..0636dec9a
--- /dev/null
+++ b/src/compress/gzip/gunzip_test.go
@@ -0,0 +1,410 @@
+// Copyright 2009 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 gzip
+
+import (
+ "bytes"
+ "io"
+ "io/ioutil"
+ "os"
+ "strings"
+ "testing"
+ "time"
+)
+
+type gunzipTest struct {
+ name string
+ desc string
+ raw string
+ gzip []byte
+ err error
+}
+
+var gunzipTests = []gunzipTest{
+ { // has 1 empty fixed-huffman block
+ "empty.txt",
+ "empty.txt",
+ "",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xf7, 0x5e, 0x14, 0x4a,
+ 0x00, 0x03, 0x65, 0x6d, 0x70, 0x74, 0x79, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0x03, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ },
+ nil,
+ },
+ { // has 1 non-empty fixed huffman block
+ "hello.txt",
+ "hello.txt",
+ "hello world\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xc8, 0x58, 0x13, 0x4a,
+ 0x00, 0x03, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0xcb, 0x48, 0xcd, 0xc9,
+ 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0xe1,
+ 0x02, 0x00, 0x2d, 0x3b, 0x08, 0xaf, 0x0c, 0x00,
+ 0x00, 0x00,
+ },
+ nil,
+ },
+ { // concatenation
+ "hello.txt",
+ "hello.txt x2",
+ "hello world\n" +
+ "hello world\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xc8, 0x58, 0x13, 0x4a,
+ 0x00, 0x03, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0xcb, 0x48, 0xcd, 0xc9,
+ 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0xe1,
+ 0x02, 0x00, 0x2d, 0x3b, 0x08, 0xaf, 0x0c, 0x00,
+ 0x00, 0x00,
+ 0x1f, 0x8b, 0x08, 0x08, 0xc8, 0x58, 0x13, 0x4a,
+ 0x00, 0x03, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0xcb, 0x48, 0xcd, 0xc9,
+ 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0xe1,
+ 0x02, 0x00, 0x2d, 0x3b, 0x08, 0xaf, 0x0c, 0x00,
+ 0x00, 0x00,
+ },
+ nil,
+ },
+ { // has a fixed huffman block with some length-distance pairs
+ "shesells.txt",
+ "shesells.txt",
+ "she sells seashells by the seashore\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0x72, 0x66, 0x8b, 0x4a,
+ 0x00, 0x03, 0x73, 0x68, 0x65, 0x73, 0x65, 0x6c,
+ 0x6c, 0x73, 0x2e, 0x74, 0x78, 0x74, 0x00, 0x2b,
+ 0xce, 0x48, 0x55, 0x28, 0x4e, 0xcd, 0xc9, 0x29,
+ 0x06, 0x92, 0x89, 0xc5, 0x19, 0x60, 0x56, 0x52,
+ 0xa5, 0x42, 0x09, 0x58, 0x18, 0x28, 0x90, 0x5f,
+ 0x94, 0xca, 0x05, 0x00, 0x76, 0xb0, 0x3b, 0xeb,
+ 0x24, 0x00, 0x00, 0x00,
+ },
+ nil,
+ },
+ { // has dynamic huffman blocks
+ "gettysburg",
+ "gettysburg",
+ " Four score and seven years ago our fathers brought forth on\n" +
+ "this continent, a new nation, conceived in Liberty, and dedicated\n" +
+ "to the proposition that all men are created equal.\n" +
+ " Now we are engaged in a great Civil War, testing whether that\n" +
+ "nation, or any nation so conceived and so dedicated, can long\n" +
+ "endure.\n" +
+ " We are met on a great battle-field of that war.\n" +
+ " We have come to dedicate a portion of that field, as a final\n" +
+ "resting place for those who here gave their lives that that\n" +
+ "nation might live. It is altogether fitting and proper that\n" +
+ "we should do this.\n" +
+ " But, in a larger sense, we can not dedicate — we can not\n" +
+ "consecrate — we can not hallow — this ground.\n" +
+ " The brave men, living and dead, who struggled here, have\n" +
+ "consecrated it, far above our poor power to add or detract.\n" +
+ "The world will little note, nor long remember what we say here,\n" +
+ "but it can never forget what they did here.\n" +
+ " It is for us the living, rather, to be dedicated here to the\n" +
+ "unfinished work which they who fought here have thus far so\n" +
+ "nobly advanced. It is rather for us to be here dedicated to\n" +
+ "the great task remaining before us — that from these honored\n" +
+ "dead we take increased devotion to that cause for which they\n" +
+ "gave the last full measure of devotion —\n" +
+ " that we here highly resolve that these dead shall not have\n" +
+ "died in vain — that this nation, under God, shall have a new\n" +
+ "birth of freedom — and that government of the people, by the\n" +
+ "people, for the people, shall not perish from this earth.\n" +
+ "\n" +
+ "Abraham Lincoln, November 19, 1863, Gettysburg, Pennsylvania\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xd1, 0x12, 0x2b, 0x4a,
+ 0x00, 0x03, 0x67, 0x65, 0x74, 0x74, 0x79, 0x73,
+ 0x62, 0x75, 0x72, 0x67, 0x00, 0x65, 0x54, 0xcd,
+ 0x6e, 0xd4, 0x30, 0x10, 0xbe, 0xfb, 0x29, 0xe6,
+ 0x01, 0x42, 0xa5, 0x0a, 0x09, 0xc1, 0x11, 0x90,
+ 0x40, 0x48, 0xa8, 0xe2, 0x80, 0xd4, 0xf3, 0x24,
+ 0x9e, 0x24, 0x56, 0xbd, 0x9e, 0xc5, 0x76, 0x76,
+ 0x95, 0x1b, 0x0f, 0xc1, 0x13, 0xf2, 0x24, 0x7c,
+ 0x63, 0x77, 0x9b, 0x4a, 0x5c, 0xaa, 0x6e, 0x6c,
+ 0xcf, 0x7c, 0x7f, 0x33, 0x44, 0x5f, 0x74, 0xcb,
+ 0x54, 0x26, 0xcd, 0x42, 0x9c, 0x3c, 0x15, 0xb9,
+ 0x48, 0xa2, 0x5d, 0x38, 0x17, 0xe2, 0x45, 0xc9,
+ 0x4e, 0x67, 0xae, 0xab, 0xe0, 0xf7, 0x98, 0x75,
+ 0x5b, 0xd6, 0x4a, 0xb3, 0xe6, 0xba, 0x92, 0x26,
+ 0x57, 0xd7, 0x50, 0x68, 0xd2, 0x54, 0x43, 0x92,
+ 0x54, 0x07, 0x62, 0x4a, 0x72, 0xa5, 0xc4, 0x35,
+ 0x68, 0x1a, 0xec, 0x60, 0x92, 0x70, 0x11, 0x4f,
+ 0x21, 0xd1, 0xf7, 0x30, 0x4a, 0xae, 0xfb, 0xd0,
+ 0x9a, 0x78, 0xf1, 0x61, 0xe2, 0x2a, 0xde, 0x55,
+ 0x25, 0xd4, 0xa6, 0x73, 0xd6, 0xb3, 0x96, 0x60,
+ 0xef, 0xf0, 0x9b, 0x2b, 0x71, 0x8c, 0x74, 0x02,
+ 0x10, 0x06, 0xac, 0x29, 0x8b, 0xdd, 0x25, 0xf9,
+ 0xb5, 0x71, 0xbc, 0x73, 0x44, 0x0f, 0x7a, 0xa5,
+ 0xab, 0xb4, 0x33, 0x49, 0x0b, 0x2f, 0xbd, 0x03,
+ 0xd3, 0x62, 0x17, 0xe9, 0x73, 0xb8, 0x84, 0x48,
+ 0x8f, 0x9c, 0x07, 0xaa, 0x52, 0x00, 0x6d, 0xa1,
+ 0xeb, 0x2a, 0xc6, 0xa0, 0x95, 0x76, 0x37, 0x78,
+ 0x9a, 0x81, 0x65, 0x7f, 0x46, 0x4b, 0x45, 0x5f,
+ 0xe1, 0x6d, 0x42, 0xe8, 0x01, 0x13, 0x5c, 0x38,
+ 0x51, 0xd4, 0xb4, 0x38, 0x49, 0x7e, 0xcb, 0x62,
+ 0x28, 0x1e, 0x3b, 0x82, 0x93, 0x54, 0x48, 0xf1,
+ 0xd2, 0x7d, 0xe4, 0x5a, 0xa3, 0xbc, 0x99, 0x83,
+ 0x44, 0x4f, 0x3a, 0x77, 0x36, 0x57, 0xce, 0xcf,
+ 0x2f, 0x56, 0xbe, 0x80, 0x90, 0x9e, 0x84, 0xea,
+ 0x51, 0x1f, 0x8f, 0xcf, 0x90, 0xd4, 0x60, 0xdc,
+ 0x5e, 0xb4, 0xf7, 0x10, 0x0b, 0x26, 0xe0, 0xff,
+ 0xc4, 0xd1, 0xe5, 0x67, 0x2e, 0xe7, 0xc8, 0x93,
+ 0x98, 0x05, 0xb8, 0xa8, 0x45, 0xc0, 0x4d, 0x09,
+ 0xdc, 0x84, 0x16, 0x2b, 0x0d, 0x9a, 0x21, 0x53,
+ 0x04, 0x8b, 0xd2, 0x0b, 0xbd, 0xa2, 0x4c, 0xa7,
+ 0x60, 0xee, 0xd9, 0xe1, 0x1d, 0xd1, 0xb7, 0x4a,
+ 0x30, 0x8f, 0x63, 0xd5, 0xa5, 0x8b, 0x33, 0x87,
+ 0xda, 0x1a, 0x18, 0x79, 0xf3, 0xe3, 0xa6, 0x17,
+ 0x94, 0x2e, 0xab, 0x6e, 0xa0, 0xe3, 0xcd, 0xac,
+ 0x50, 0x8c, 0xca, 0xa7, 0x0d, 0x76, 0x37, 0xd1,
+ 0x23, 0xe7, 0x05, 0x57, 0x8b, 0xa4, 0x22, 0x83,
+ 0xd9, 0x62, 0x52, 0x25, 0xad, 0x07, 0xbb, 0xbf,
+ 0xbf, 0xff, 0xbc, 0xfa, 0xee, 0x20, 0x73, 0x91,
+ 0x29, 0xff, 0x7f, 0x02, 0x71, 0x62, 0x84, 0xb5,
+ 0xf6, 0xb5, 0x25, 0x6b, 0x41, 0xde, 0x92, 0xb7,
+ 0x76, 0x3f, 0x91, 0x91, 0x31, 0x1b, 0x41, 0x84,
+ 0x62, 0x30, 0x0a, 0x37, 0xa4, 0x5e, 0x18, 0x3a,
+ 0x99, 0x08, 0xa5, 0xe6, 0x6d, 0x59, 0x22, 0xec,
+ 0x33, 0x39, 0x86, 0x26, 0xf5, 0xab, 0x66, 0xc8,
+ 0x08, 0x20, 0xcf, 0x0c, 0xd7, 0x47, 0x45, 0x21,
+ 0x0b, 0xf6, 0x59, 0xd5, 0xfe, 0x5c, 0x8d, 0xaa,
+ 0x12, 0x7b, 0x6f, 0xa1, 0xf0, 0x52, 0x33, 0x4f,
+ 0xf5, 0xce, 0x59, 0xd3, 0xab, 0x66, 0x10, 0xbf,
+ 0x06, 0xc4, 0x31, 0x06, 0x73, 0xd6, 0x80, 0xa2,
+ 0x78, 0xc2, 0x45, 0xcb, 0x03, 0x65, 0x39, 0xc9,
+ 0x09, 0xd1, 0x06, 0x04, 0x33, 0x1a, 0x5a, 0xf1,
+ 0xde, 0x01, 0xb8, 0x71, 0x83, 0xc4, 0xb5, 0xb3,
+ 0xc3, 0x54, 0x65, 0x33, 0x0d, 0x5a, 0xf7, 0x9b,
+ 0x90, 0x7c, 0x27, 0x1f, 0x3a, 0x58, 0xa3, 0xd8,
+ 0xfd, 0x30, 0x5f, 0xb7, 0xd2, 0x66, 0xa2, 0x93,
+ 0x1c, 0x28, 0xb7, 0xe9, 0x1b, 0x0c, 0xe1, 0x28,
+ 0x47, 0x26, 0xbb, 0xe9, 0x7d, 0x7e, 0xdc, 0x96,
+ 0x10, 0x92, 0x50, 0x56, 0x7c, 0x06, 0xe2, 0x27,
+ 0xb4, 0x08, 0xd3, 0xda, 0x7b, 0x98, 0x34, 0x73,
+ 0x9f, 0xdb, 0xf6, 0x62, 0xed, 0x31, 0x41, 0x13,
+ 0xd3, 0xa2, 0xa8, 0x4b, 0x3a, 0xc6, 0x1d, 0xe4,
+ 0x2f, 0x8c, 0xf8, 0xfb, 0x97, 0x64, 0xf4, 0xb6,
+ 0x2f, 0x80, 0x5a, 0xf3, 0x56, 0xe0, 0x40, 0x50,
+ 0xd5, 0x19, 0xd0, 0x1e, 0xfc, 0xca, 0xe5, 0xc9,
+ 0xd4, 0x60, 0x00, 0x81, 0x2e, 0xa3, 0xcc, 0xb6,
+ 0x52, 0xf0, 0xb4, 0xdb, 0x69, 0x99, 0xce, 0x7a,
+ 0x32, 0x4c, 0x08, 0xed, 0xaa, 0x10, 0x10, 0xe3,
+ 0x6f, 0xee, 0x99, 0x68, 0x95, 0x9f, 0x04, 0x71,
+ 0xb2, 0x49, 0x2f, 0x62, 0xa6, 0x5e, 0xb4, 0xef,
+ 0x02, 0xed, 0x4f, 0x27, 0xde, 0x4a, 0x0f, 0xfd,
+ 0xc1, 0xcc, 0xdd, 0x02, 0x8f, 0x08, 0x16, 0x54,
+ 0xdf, 0xda, 0xca, 0xe0, 0x82, 0xf1, 0xb4, 0x31,
+ 0x7a, 0xa9, 0x81, 0xfe, 0x90, 0xb7, 0x3e, 0xdb,
+ 0xd3, 0x35, 0xc0, 0x20, 0x80, 0x33, 0x46, 0x4a,
+ 0x63, 0xab, 0xd1, 0x0d, 0x29, 0xd2, 0xe2, 0x84,
+ 0xb8, 0xdb, 0xfa, 0xe9, 0x89, 0x44, 0x86, 0x7c,
+ 0xe8, 0x0b, 0xe6, 0x02, 0x6a, 0x07, 0x9b, 0x96,
+ 0xd0, 0xdb, 0x2e, 0x41, 0x4c, 0xa1, 0xd5, 0x57,
+ 0x45, 0x14, 0xfb, 0xe3, 0xa6, 0x72, 0x5b, 0x87,
+ 0x6e, 0x0c, 0x6d, 0x5b, 0xce, 0xe0, 0x2f, 0xe2,
+ 0x21, 0x81, 0x95, 0xb0, 0xe8, 0xb6, 0x32, 0x0b,
+ 0xb2, 0x98, 0x13, 0x52, 0x5d, 0xfb, 0xec, 0x63,
+ 0x17, 0x8a, 0x9e, 0x23, 0x22, 0x36, 0xee, 0xcd,
+ 0xda, 0xdb, 0xcf, 0x3e, 0xf1, 0xc7, 0xf1, 0x01,
+ 0x12, 0x93, 0x0a, 0xeb, 0x6f, 0xf2, 0x02, 0x15,
+ 0x96, 0x77, 0x5d, 0xef, 0x9c, 0xfb, 0x88, 0x91,
+ 0x59, 0xf9, 0x84, 0xdd, 0x9b, 0x26, 0x8d, 0x80,
+ 0xf9, 0x80, 0x66, 0x2d, 0xac, 0xf7, 0x1f, 0x06,
+ 0xba, 0x7f, 0xff, 0xee, 0xed, 0x40, 0x5f, 0xa5,
+ 0xd6, 0xbd, 0x8c, 0x5b, 0x46, 0xd2, 0x7e, 0x48,
+ 0x4a, 0x65, 0x8f, 0x08, 0x42, 0x60, 0xf7, 0x0f,
+ 0xb9, 0x16, 0x0b, 0x0c, 0x1a, 0x06, 0x00, 0x00,
+ },
+ nil,
+ },
+ { // has 1 non-empty fixed huffman block then garbage
+ "hello.txt",
+ "hello.txt + garbage",
+ "hello world\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xc8, 0x58, 0x13, 0x4a,
+ 0x00, 0x03, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0xcb, 0x48, 0xcd, 0xc9,
+ 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0xe1,
+ 0x02, 0x00, 0x2d, 0x3b, 0x08, 0xaf, 0x0c, 0x00,
+ 0x00, 0x00, 'g', 'a', 'r', 'b', 'a', 'g', 'e', '!', '!', '!',
+ },
+ ErrHeader,
+ },
+ { // has 1 non-empty fixed huffman block not enough header
+ "hello.txt",
+ "hello.txt + garbage",
+ "hello world\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xc8, 0x58, 0x13, 0x4a,
+ 0x00, 0x03, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0xcb, 0x48, 0xcd, 0xc9,
+ 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0xe1,
+ 0x02, 0x00, 0x2d, 0x3b, 0x08, 0xaf, 0x0c, 0x00,
+ 0x00, 0x00, gzipID1,
+ },
+ io.ErrUnexpectedEOF,
+ },
+ { // has 1 non-empty fixed huffman block but corrupt checksum
+ "hello.txt",
+ "hello.txt + corrupt checksum",
+ "hello world\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xc8, 0x58, 0x13, 0x4a,
+ 0x00, 0x03, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0xcb, 0x48, 0xcd, 0xc9,
+ 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0xe1,
+ 0x02, 0x00, 0xff, 0xff, 0xff, 0xff, 0x0c, 0x00,
+ 0x00, 0x00,
+ },
+ ErrChecksum,
+ },
+ { // has 1 non-empty fixed huffman block but corrupt size
+ "hello.txt",
+ "hello.txt + corrupt size",
+ "hello world\n",
+ []byte{
+ 0x1f, 0x8b, 0x08, 0x08, 0xc8, 0x58, 0x13, 0x4a,
+ 0x00, 0x03, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x2e,
+ 0x74, 0x78, 0x74, 0x00, 0xcb, 0x48, 0xcd, 0xc9,
+ 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0xe1,
+ 0x02, 0x00, 0x2d, 0x3b, 0x08, 0xaf, 0xff, 0x00,
+ 0x00, 0x00,
+ },
+ ErrChecksum,
+ },
+}
+
+func TestDecompressor(t *testing.T) {
+ b := new(bytes.Buffer)
+ for _, tt := range gunzipTests {
+ in := bytes.NewReader(tt.gzip)
+ gzip, err := NewReader(in)
+ if err != nil {
+ t.Errorf("%s: NewReader: %s", tt.name, err)
+ continue
+ }
+ defer gzip.Close()
+ if tt.name != gzip.Name {
+ t.Errorf("%s: got name %s", tt.name, gzip.Name)
+ }
+ b.Reset()
+ n, err := io.Copy(b, gzip)
+ if err != tt.err {
+ t.Errorf("%s: io.Copy: %v want %v", tt.name, err, tt.err)
+ }
+ s := b.String()
+ if s != tt.raw {
+ t.Errorf("%s: got %d-byte %q want %d-byte %q", tt.name, n, s, len(tt.raw), tt.raw)
+ }
+
+ // Test Reader Reset.
+ in = bytes.NewReader(tt.gzip)
+ err = gzip.Reset(in)
+ if err != nil {
+ t.Errorf("%s: Reset: %s", tt.name, err)
+ continue
+ }
+ if tt.name != gzip.Name {
+ t.Errorf("%s: got name %s", tt.name, gzip.Name)
+ }
+ b.Reset()
+ n, err = io.Copy(b, gzip)
+ if err != tt.err {
+ t.Errorf("%s: io.Copy: %v want %v", tt.name, err, tt.err)
+ }
+ s = b.String()
+ if s != tt.raw {
+ t.Errorf("%s: got %d-byte %q want %d-byte %q", tt.name, n, s, len(tt.raw), tt.raw)
+ }
+ }
+}
+
+func TestIssue6550(t *testing.T) {
+ f, err := os.Open("testdata/issue6550.gz")
+ if err != nil {
+ t.Fatal(err)
+ }
+ gzip, err := NewReader(f)
+ if err != nil {
+ t.Fatalf("NewReader(testdata/issue6550.gz): %v", err)
+ }
+ defer gzip.Close()
+ done := make(chan bool, 1)
+ go func() {
+ _, err := io.Copy(ioutil.Discard, gzip)
+ if err == nil {
+ t.Errorf("Copy succeeded")
+ } else {
+ t.Logf("Copy failed (correctly): %v", err)
+ }
+ done <- true
+ }()
+ select {
+ case <-time.After(1 * time.Second):
+ t.Errorf("Copy hung")
+ case <-done:
+ // ok
+ }
+}
+
+func TestInitialReset(t *testing.T) {
+ var r Reader
+ if err := r.Reset(bytes.NewReader(gunzipTests[1].gzip)); err != nil {
+ t.Error(err)
+ }
+ var buf bytes.Buffer
+ if _, err := io.Copy(&buf, &r); err != nil {
+ t.Error(err)
+ }
+ if s := buf.String(); s != gunzipTests[1].raw {
+ t.Errorf("got %q want %q", s, gunzipTests[1].raw)
+ }
+}
+
+func TestMultistreamFalse(t *testing.T) {
+ // Find concatenation test.
+ var tt gunzipTest
+ for _, tt = range gunzipTests {
+ if strings.HasSuffix(tt.desc, " x2") {
+ goto Found
+ }
+ }
+ t.Fatal("cannot find hello.txt x2 in gunzip tests")
+
+Found:
+ br := bytes.NewReader(tt.gzip)
+ var r Reader
+ if err := r.Reset(br); err != nil {
+ t.Fatalf("first reset: %v", err)
+ }
+
+ // Expect two streams with "hello world\n", then real EOF.
+ const hello = "hello world\n"
+
+ r.Multistream(false)
+ data, err := ioutil.ReadAll(&r)
+ if string(data) != hello || err != nil {
+ t.Fatalf("first stream = %q, %v, want %q, %v", string(data), err, hello, nil)
+ }
+
+ if err := r.Reset(br); err != nil {
+ t.Fatalf("second reset: %v", err)
+ }
+ r.Multistream(false)
+ data, err = ioutil.ReadAll(&r)
+ if string(data) != hello || err != nil {
+ t.Fatalf("second stream = %q, %v, want %q, %v", string(data), err, hello, nil)
+ }
+
+ if err := r.Reset(br); err != io.EOF {
+ t.Fatalf("third reset: err=%v, want io.EOF", err)
+ }
+}
diff --git a/src/compress/gzip/gzip.go b/src/compress/gzip/gzip.go
new file mode 100644
index 000000000..5131d128e
--- /dev/null
+++ b/src/compress/gzip/gzip.go
@@ -0,0 +1,272 @@
+// Copyright 2010 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 gzip
+
+import (
+ "compress/flate"
+ "errors"
+ "fmt"
+ "hash"
+ "hash/crc32"
+ "io"
+)
+
+// These constants are copied from the flate package, so that code that imports
+// "compress/gzip" does not also have to import "compress/flate".
+const (
+ NoCompression = flate.NoCompression
+ BestSpeed = flate.BestSpeed
+ BestCompression = flate.BestCompression
+ DefaultCompression = flate.DefaultCompression
+)
+
+// A Writer is an io.WriteCloser.
+// Writes to a Writer are compressed and written to w.
+type Writer struct {
+ Header
+ w io.Writer
+ level int
+ wroteHeader bool
+ compressor *flate.Writer
+ digest hash.Hash32
+ size uint32
+ closed bool
+ buf [10]byte
+ err error
+}
+
+// NewWriter returns a new Writer.
+// Writes to the returned writer are compressed and written to w.
+//
+// It is the caller's responsibility to call Close on the WriteCloser when done.
+// Writes may be buffered and not flushed until Close.
+//
+// Callers that wish to set the fields in Writer.Header must do so before
+// the first call to Write or Close. The Comment and Name header fields are
+// UTF-8 strings in Go, but the underlying format requires NUL-terminated ISO
+// 8859-1 (Latin-1). NUL or non-Latin-1 runes in those strings will lead to an
+// error on Write.
+func NewWriter(w io.Writer) *Writer {
+ z, _ := NewWriterLevel(w, DefaultCompression)
+ return z
+}
+
+// NewWriterLevel is like NewWriter but specifies the compression level instead
+// of assuming DefaultCompression.
+//
+// The compression level can be DefaultCompression, NoCompression, or any
+// integer value between BestSpeed and BestCompression inclusive. The error
+// returned will be nil if the level is valid.
+func NewWriterLevel(w io.Writer, level int) (*Writer, error) {
+ if level < DefaultCompression || level > BestCompression {
+ return nil, fmt.Errorf("gzip: invalid compression level: %d", level)
+ }
+ z := new(Writer)
+ z.init(w, level)
+ return z, nil
+}
+
+func (z *Writer) init(w io.Writer, level int) {
+ digest := z.digest
+ if digest != nil {
+ digest.Reset()
+ } else {
+ digest = crc32.NewIEEE()
+ }
+ compressor := z.compressor
+ if compressor != nil {
+ compressor.Reset(w)
+ }
+ *z = Writer{
+ Header: Header{
+ OS: 255, // unknown
+ },
+ w: w,
+ level: level,
+ digest: digest,
+ compressor: compressor,
+ }
+}
+
+// Reset discards the Writer z's state and makes it equivalent to the
+// result of its original state from NewWriter or NewWriterLevel, but
+// writing to w instead. This permits reusing a Writer rather than
+// allocating a new one.
+func (z *Writer) Reset(w io.Writer) {
+ z.init(w, z.level)
+}
+
+// GZIP (RFC 1952) is little-endian, unlike ZLIB (RFC 1950).
+func put2(p []byte, v uint16) {
+ p[0] = uint8(v >> 0)
+ p[1] = uint8(v >> 8)
+}
+
+func put4(p []byte, v uint32) {
+ p[0] = uint8(v >> 0)
+ p[1] = uint8(v >> 8)
+ p[2] = uint8(v >> 16)
+ p[3] = uint8(v >> 24)
+}
+
+// writeBytes writes a length-prefixed byte slice to z.w.
+func (z *Writer) writeBytes(b []byte) error {
+ if len(b) > 0xffff {
+ return errors.New("gzip.Write: Extra data is too large")
+ }
+ put2(z.buf[0:2], uint16(len(b)))
+ _, err := z.w.Write(z.buf[0:2])
+ if err != nil {
+ return err
+ }
+ _, err = z.w.Write(b)
+ return err
+}
+
+// writeString writes a UTF-8 string s in GZIP's format to z.w.
+// GZIP (RFC 1952) specifies that strings are NUL-terminated ISO 8859-1 (Latin-1).
+func (z *Writer) writeString(s string) (err error) {
+ // GZIP stores Latin-1 strings; error if non-Latin-1; convert if non-ASCII.
+ needconv := false
+ for _, v := range s {
+ if v == 0 || v > 0xff {
+ return errors.New("gzip.Write: non-Latin-1 header string")
+ }
+ if v > 0x7f {
+ needconv = true
+ }
+ }
+ if needconv {
+ b := make([]byte, 0, len(s))
+ for _, v := range s {
+ b = append(b, byte(v))
+ }
+ _, err = z.w.Write(b)
+ } else {
+ _, err = io.WriteString(z.w, s)
+ }
+ if err != nil {
+ return err
+ }
+ // GZIP strings are NUL-terminated.
+ z.buf[0] = 0
+ _, err = z.w.Write(z.buf[0:1])
+ return err
+}
+
+// Write writes a compressed form of p to the underlying io.Writer. The
+// compressed bytes are not necessarily flushed until the Writer is closed.
+func (z *Writer) Write(p []byte) (int, error) {
+ if z.err != nil {
+ return 0, z.err
+ }
+ var n int
+ // Write the GZIP header lazily.
+ if !z.wroteHeader {
+ z.wroteHeader = true
+ z.buf[0] = gzipID1
+ z.buf[1] = gzipID2
+ z.buf[2] = gzipDeflate
+ z.buf[3] = 0
+ if z.Extra != nil {
+ z.buf[3] |= 0x04
+ }
+ if z.Name != "" {
+ z.buf[3] |= 0x08
+ }
+ if z.Comment != "" {
+ z.buf[3] |= 0x10
+ }
+ put4(z.buf[4:8], uint32(z.ModTime.Unix()))
+ if z.level == BestCompression {
+ z.buf[8] = 2
+ } else if z.level == BestSpeed {
+ z.buf[8] = 4
+ } else {
+ z.buf[8] = 0
+ }
+ z.buf[9] = z.OS
+ n, z.err = z.w.Write(z.buf[0:10])
+ if z.err != nil {
+ return n, z.err
+ }
+ if z.Extra != nil {
+ z.err = z.writeBytes(z.Extra)
+ if z.err != nil {
+ return n, z.err
+ }
+ }
+ if z.Name != "" {
+ z.err = z.writeString(z.Name)
+ if z.err != nil {
+ return n, z.err
+ }
+ }
+ if z.Comment != "" {
+ z.err = z.writeString(z.Comment)
+ if z.err != nil {
+ return n, z.err
+ }
+ }
+ if z.compressor == nil {
+ z.compressor, _ = flate.NewWriter(z.w, z.level)
+ }
+ }
+ z.size += uint32(len(p))
+ z.digest.Write(p)
+ n, z.err = z.compressor.Write(p)
+ return n, z.err
+}
+
+// Flush flushes any pending compressed data to the underlying writer.
+//
+// It is useful mainly in compressed network protocols, to ensure that
+// a remote reader has enough data to reconstruct a packet. Flush does
+// not return until the data has been written. If the underlying
+// writer returns an error, Flush returns that error.
+//
+// In the terminology of the zlib library, Flush is equivalent to Z_SYNC_FLUSH.
+func (z *Writer) Flush() error {
+ if z.err != nil {
+ return z.err
+ }
+ if z.closed {
+ return nil
+ }
+ if !z.wroteHeader {
+ z.Write(nil)
+ if z.err != nil {
+ return z.err
+ }
+ }
+ z.err = z.compressor.Flush()
+ return z.err
+}
+
+// Close closes the Writer, flushing any unwritten data to the underlying
+// io.Writer, but does not close the underlying io.Writer.
+func (z *Writer) Close() error {
+ if z.err != nil {
+ return z.err
+ }
+ if z.closed {
+ return nil
+ }
+ z.closed = true
+ if !z.wroteHeader {
+ z.Write(nil)
+ if z.err != nil {
+ return z.err
+ }
+ }
+ z.err = z.compressor.Close()
+ if z.err != nil {
+ return z.err
+ }
+ put4(z.buf[0:4], z.digest.Sum32())
+ put4(z.buf[4:8], z.size)
+ _, z.err = z.w.Write(z.buf[0:8])
+ return z.err
+}
diff --git a/src/compress/gzip/gzip_test.go b/src/compress/gzip/gzip_test.go
new file mode 100644
index 000000000..09271b24e
--- /dev/null
+++ b/src/compress/gzip/gzip_test.go
@@ -0,0 +1,231 @@
+// Copyright 2010 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 gzip
+
+import (
+ "bufio"
+ "bytes"
+ "io/ioutil"
+ "testing"
+ "time"
+)
+
+// TestEmpty tests that an empty payload still forms a valid GZIP stream.
+func TestEmpty(t *testing.T) {
+ buf := new(bytes.Buffer)
+
+ if err := NewWriter(buf).Close(); err != nil {
+ t.Fatalf("Writer.Close: %v", err)
+ }
+
+ r, err := NewReader(buf)
+ if err != nil {
+ t.Fatalf("NewReader: %v", err)
+ }
+ b, err := ioutil.ReadAll(r)
+ if err != nil {
+ t.Fatalf("ReadAll: %v", err)
+ }
+ if len(b) != 0 {
+ t.Fatalf("got %d bytes, want 0", len(b))
+ }
+ if err := r.Close(); err != nil {
+ t.Fatalf("Reader.Close: %v", err)
+ }
+}
+
+// TestRoundTrip tests that gzipping and then gunzipping is the identity
+// function.
+func TestRoundTrip(t *testing.T) {
+ buf := new(bytes.Buffer)
+
+ w := NewWriter(buf)
+ w.Comment = "comment"
+ w.Extra = []byte("extra")
+ w.ModTime = time.Unix(1e8, 0)
+ w.Name = "name"
+ if _, err := w.Write([]byte("payload")); err != nil {
+ t.Fatalf("Write: %v", err)
+ }
+ if err := w.Close(); err != nil {
+ t.Fatalf("Writer.Close: %v", err)
+ }
+
+ r, err := NewReader(buf)
+ if err != nil {
+ t.Fatalf("NewReader: %v", err)
+ }
+ b, err := ioutil.ReadAll(r)
+ if err != nil {
+ t.Fatalf("ReadAll: %v", err)
+ }
+ if string(b) != "payload" {
+ t.Fatalf("payload is %q, want %q", string(b), "payload")
+ }
+ if r.Comment != "comment" {
+ t.Fatalf("comment is %q, want %q", r.Comment, "comment")
+ }
+ if string(r.Extra) != "extra" {
+ t.Fatalf("extra is %q, want %q", r.Extra, "extra")
+ }
+ if r.ModTime.Unix() != 1e8 {
+ t.Fatalf("mtime is %d, want %d", r.ModTime.Unix(), uint32(1e8))
+ }
+ if r.Name != "name" {
+ t.Fatalf("name is %q, want %q", r.Name, "name")
+ }
+ if err := r.Close(); err != nil {
+ t.Fatalf("Reader.Close: %v", err)
+ }
+}
+
+// TestLatin1 tests the internal functions for converting to and from Latin-1.
+func TestLatin1(t *testing.T) {
+ latin1 := []byte{0xc4, 'u', 0xdf, 'e', 'r', 'u', 'n', 'g', 0}
+ utf8 := "Äußerung"
+ z := Reader{r: bufio.NewReader(bytes.NewReader(latin1))}
+ s, err := z.readString()
+ if err != nil {
+ t.Fatalf("readString: %v", err)
+ }
+ if s != utf8 {
+ t.Fatalf("read latin-1: got %q, want %q", s, utf8)
+ }
+
+ buf := bytes.NewBuffer(make([]byte, 0, len(latin1)))
+ c := Writer{w: buf}
+ if err = c.writeString(utf8); err != nil {
+ t.Fatalf("writeString: %v", err)
+ }
+ s = buf.String()
+ if s != string(latin1) {
+ t.Fatalf("write utf-8: got %q, want %q", s, string(latin1))
+ }
+}
+
+// TestLatin1RoundTrip tests that metadata that is representable in Latin-1
+// survives a round trip.
+func TestLatin1RoundTrip(t *testing.T) {
+ testCases := []struct {
+ name string
+ ok bool
+ }{
+ {"", true},
+ {"ASCII is OK", true},
+ {"unless it contains a NUL\x00", false},
+ {"no matter where \x00 occurs", false},
+ {"\x00\x00\x00", false},
+ {"Látin-1 also passes (U+00E1)", true},
+ {"but LĀtin Extended-A (U+0100) does not", false},
+ {"neither does 日本語", false},
+ {"invalid UTF-8 also \xffails", false},
+ {"\x00 as does Látin-1 with NUL", false},
+ }
+ for _, tc := range testCases {
+ buf := new(bytes.Buffer)
+
+ w := NewWriter(buf)
+ w.Name = tc.name
+ err := w.Close()
+ if (err == nil) != tc.ok {
+ t.Errorf("Writer.Close: name = %q, err = %v", tc.name, err)
+ continue
+ }
+ if !tc.ok {
+ continue
+ }
+
+ r, err := NewReader(buf)
+ if err != nil {
+ t.Errorf("NewReader: %v", err)
+ continue
+ }
+ _, err = ioutil.ReadAll(r)
+ if err != nil {
+ t.Errorf("ReadAll: %v", err)
+ continue
+ }
+ if r.Name != tc.name {
+ t.Errorf("name is %q, want %q", r.Name, tc.name)
+ continue
+ }
+ if err := r.Close(); err != nil {
+ t.Errorf("Reader.Close: %v", err)
+ continue
+ }
+ }
+}
+
+func TestWriterFlush(t *testing.T) {
+ buf := new(bytes.Buffer)
+
+ w := NewWriter(buf)
+ w.Comment = "comment"
+ w.Extra = []byte("extra")
+ w.ModTime = time.Unix(1e8, 0)
+ w.Name = "name"
+
+ n0 := buf.Len()
+ if n0 != 0 {
+ t.Fatalf("buffer size = %d before writes; want 0", n0)
+ }
+
+ if err := w.Flush(); err != nil {
+ t.Fatal(err)
+ }
+
+ n1 := buf.Len()
+ if n1 == 0 {
+ t.Fatal("no data after first flush")
+ }
+
+ w.Write([]byte("x"))
+
+ n2 := buf.Len()
+ if n1 != n2 {
+ t.Fatalf("after writing a single byte, size changed from %d to %d; want no change", n1, n2)
+ }
+
+ if err := w.Flush(); err != nil {
+ t.Fatal(err)
+ }
+
+ n3 := buf.Len()
+ if n2 == n3 {
+ t.Fatal("Flush didn't flush any data")
+ }
+}
+
+// Multiple gzip files concatenated form a valid gzip file.
+func TestConcat(t *testing.T) {
+ var buf bytes.Buffer
+ w := NewWriter(&buf)
+ w.Write([]byte("hello "))
+ w.Close()
+ w = NewWriter(&buf)
+ w.Write([]byte("world\n"))
+ w.Close()
+
+ r, err := NewReader(&buf)
+ data, err := ioutil.ReadAll(r)
+ if string(data) != "hello world\n" || err != nil {
+ t.Fatalf("ReadAll = %q, %v, want %q, nil", data, err, "hello world")
+ }
+}
+
+func TestWriterReset(t *testing.T) {
+ buf := new(bytes.Buffer)
+ buf2 := new(bytes.Buffer)
+ z := NewWriter(buf)
+ msg := []byte("hello world")
+ z.Write(msg)
+ z.Close()
+ z.Reset(buf2)
+ z.Write(msg)
+ z.Close()
+ if buf.String() != buf2.String() {
+ t.Errorf("buf2 %q != original buf of %q", buf2.String(), buf.String())
+ }
+}
diff --git a/src/compress/gzip/testdata/issue6550.gz b/src/compress/gzip/testdata/issue6550.gz
new file mode 100644
index 000000000..57972b636
--- /dev/null
+++ b/src/compress/gzip/testdata/issue6550.gz
Binary files differ
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-01 15:31:02 +0000