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path: root/src/pkg/compress/gzip/gunzip.go
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Diffstat (limited to 'src/pkg/compress/gzip/gunzip.go')
-rw-r--r--src/pkg/compress/gzip/gunzip.go89
1 files changed, 50 insertions, 39 deletions
diff --git a/src/pkg/compress/gzip/gunzip.go b/src/pkg/compress/gzip/gunzip.go
index 6ac9293d7..33736f635 100644
--- a/src/pkg/compress/gzip/gunzip.go
+++ b/src/pkg/compress/gzip/gunzip.go
@@ -9,15 +9,13 @@ package gzip
import (
"bufio"
"compress/flate"
+ "errors"
"hash"
"hash/crc32"
"io"
- "os"
+ "time"
)
-// BUG(nigeltao): Comments and Names don't properly map UTF-8 character codes outside of
-// the 0x00-0x7f range to ISO 8859-1 (Latin-1).
-
const (
gzipID1 = 0x1f
gzipID2 = 0x8b
@@ -36,34 +34,38 @@ func makeReader(r io.Reader) flate.Reader {
return bufio.NewReader(r)
}
-var HeaderError = os.NewError("invalid gzip header")
-var ChecksumError = os.NewError("gzip checksum error")
+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 Compressor and Decompressor structs.
+// That header is exposed as the fields of the Writer and Reader structs.
type Header struct {
- Comment string // comment
- Extra []byte // "extra data"
- Mtime uint32 // modification time (seconds since January 1, 1970)
- Name string // file name
- OS byte // operating system type
+ Comment string // comment
+ Extra []byte // "extra data"
+ ModTime time.Time // modification time
+ Name string // file name
+ OS byte // operating system type
}
-// An Decompressor is an io.Reader that can be read to retrieve
+// 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 Decompressor
+// 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 Decompressor fields.
+// Only the first header is recorded in the Reader fields.
//
// Gzip files store a length and checksum of the uncompressed data.
-// The Decompressor will return a ChecksumError when Read
+// 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 successful
-// (zero length, nil error) Read marking the end of the data.
-type Decompressor struct {
+// 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
@@ -71,18 +73,17 @@ type Decompressor struct {
size uint32
flg byte
buf [512]byte
- err os.Error
+ err error
}
-// NewReader creates a new Decompressor reading the given reader.
+// NewReader creates a new Reader reading the given reader.
// The implementation buffers input and may read more data than necessary from r.
-// It is the caller's responsibility to call Close on the Decompressor when done.
-func NewReader(r io.Reader) (*Decompressor, os.Error) {
- z := new(Decompressor)
+// 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.digest = crc32.NewIEEE()
if err := z.readHeader(true); err != nil {
- z.err = err
return nil, err
}
return z, nil
@@ -93,26 +94,36 @@ func get4(p []byte) uint32 {
return uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 | uint32(p[3])<<24
}
-func (z *Decompressor) readString() (string, os.Error) {
- var err os.Error
+func (z *Reader) readString() (string, error) {
+ var err error
+ needconv := false
for i := 0; ; i++ {
if i >= len(z.buf) {
- return "", HeaderError
+ 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).
- // TODO(nigeltao): Convert from ISO 8859-1 (Latin-1) to UTF-8.
+ 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
}
}
panic("not reached")
}
-func (z *Decompressor) read2() (uint32, os.Error) {
+func (z *Reader) read2() (uint32, error) {
_, err := io.ReadFull(z.r, z.buf[0:2])
if err != nil {
return 0, err
@@ -120,17 +131,17 @@ func (z *Decompressor) read2() (uint32, os.Error) {
return uint32(z.buf[0]) | uint32(z.buf[1])<<8, nil
}
-func (z *Decompressor) readHeader(save bool) os.Error {
+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 HeaderError
+ return ErrHeader
}
z.flg = z.buf[3]
if save {
- z.Mtime = get4(z.buf[4:8])
+ z.ModTime = time.Unix(int64(get4(z.buf[4:8])), 0)
// z.buf[8] is xfl, ignored
z.OS = z.buf[9]
}
@@ -177,7 +188,7 @@ func (z *Decompressor) readHeader(save bool) os.Error {
}
sum := z.digest.Sum32() & 0xFFFF
if n != sum {
- return HeaderError
+ return ErrHeader
}
}
@@ -186,7 +197,7 @@ func (z *Decompressor) readHeader(save bool) os.Error {
return nil
}
-func (z *Decompressor) Read(p []byte) (n int, err os.Error) {
+func (z *Reader) Read(p []byte) (n int, err error) {
if z.err != nil {
return 0, z.err
}
@@ -197,7 +208,7 @@ func (z *Decompressor) Read(p []byte) (n int, err os.Error) {
n, err = z.decompressor.Read(p)
z.digest.Write(p[0:n])
z.size += uint32(n)
- if n != 0 || err != os.EOF {
+ if n != 0 || err != io.EOF {
z.err = err
return
}
@@ -210,7 +221,7 @@ func (z *Decompressor) Read(p []byte) (n int, err os.Error) {
crc32, isize := get4(z.buf[0:4]), get4(z.buf[4:8])
sum := z.digest.Sum32()
if sum != crc32 || isize != z.size {
- z.err = ChecksumError
+ z.err = ErrChecksum
return 0, z.err
}
@@ -226,5 +237,5 @@ func (z *Decompressor) Read(p []byte) (n int, err os.Error) {
return z.Read(p)
}
-// Calling Close does not close the wrapped io.Reader originally passed to NewReader.
-func (z *Decompressor) Close() os.Error { return z.decompressor.Close() }
+// Close closes the Reader. It does not close the underlying io.Reader.
+func (z *Reader) Close() error { return z.decompressor.Close() }
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-22 19:04:54 +0000