Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

archive/zip: zip64 support

Browse source 
R=golang-dev, r, adg
CC=golang-dev
https://golang.org/cl/6463050
This commit is contained in:
Joakim Sernbrant 2012-08-22 11:05:24 +10:00 • committed by Andrew Gerrand
parent 7e3ebaacd8
commit 2e6d0968e3
6 changed files with 395 additions and 73 deletions
Download patch file Download diff file Expand all files Collapse all files

93
src/pkg/archive/zip/struct.go
View file

@ -7,12 +7,19 @@ Package zip provides support for reading and writing ZIP archives.
See: http://www.pkware.com/documents/casestudies/APPNOTE.TXT
This package does not support ZIP64 or disk spanning.
This package does not support disk spanning.
A note about ZIP64:
To be backwards compatible the FileHeader has both 32 and 64 bit Size
fields. The 64 bit fields will always contain the correct value and
for normal archives both fields will be the same. For files requiring
the ZIP64 format the 32 bit fields will be 0xffffffff and the 64 bit
fields must be used instead.
*/
package zip
import (
"errors"
"os"
"time"
)
@ -27,11 +34,16 @@ const (
fileHeaderSignature = 0x04034b50
directoryHeaderSignature = 0x02014b50
directoryEndSignature = 0x06054b50
directory64LocSignature = 0x07064b50
directory64EndSignature = 0x06064b50
dataDescriptorSignature = 0x08074b50 // de-facto standard; required by OS X Finder
fileHeaderLen = 30 // + filename + extra
directoryHeaderLen = 46 // + filename + extra + comment
directoryEndLen = 22 // + comment
dataDescriptorLen = 16 // four uint32: descriptor signature, crc32, compressed size, size
dataDescriptor64Len = 24 // descriptor with 8 byte sizes
directory64LocLen = 20 //
directory64EndLen = 56 // + extra
// Constants for the first byte in CreatorVersion
creatorFAT = 0
@ -39,22 +51,35 @@ const (
creatorNTFS = 11
creatorVFAT = 14
creatorMacOSX = 19
// version numbers
zipVersion20 = 20 // 2.0
zipVersion45 = 45 // 4.5 (reads and writes zip64 archives)
// limits for non zip64 files
uint16max = (1 << 16) - 1
uint32max = (1 << 32) - 1
// extra header id's
zip64ExtraId = 0x0001 // zip64 Extended Information Extra Field
)
type FileHeader struct {
Name string
CreatorVersion uint16
ReaderVersion uint16
Flags uint16
Method uint16
ModifiedTime uint16 // MS-DOS time
ModifiedDate uint16 // MS-DOS date
CRC32 uint32
CompressedSize uint32
UncompressedSize uint32
Extra []byte
ExternalAttrs uint32 // Meaning depends on CreatorVersion
Comment string
Name string
CreatorVersion uint16
ReaderVersion uint16
Flags uint16
Method uint16
ModifiedTime uint16 // MS-DOS time
ModifiedDate uint16 // MS-DOS date
CRC32 uint32
CompressedSize uint32 // deprecated; use CompressedSize64
UncompressedSize uint32 // deprecated; use UncompressedSize64
CompressedSize64 uint64
UncompressedSize64 uint64
Extra []byte
ExternalAttrs uint32 // Meaning depends on CreatorVersion
Comment string
}
// FileInfo returns an os.FileInfo for the FileHeader.
@ -67,8 +92,13 @@ type headerFileInfo struct {
fh *FileHeader
}
func (fi headerFileInfo) Name() string { return fi.fh.Name }
func (fi headerFileInfo) Size() int64 { return int64(fi.fh.UncompressedSize) }
func (fi headerFileInfo) Name() string { return fi.fh.Name }
func (fi headerFileInfo) Size() int64 {
if fi.fh.UncompressedSize64 > 0 {
return int64(fi.fh.UncompressedSize64)
}
return int64(fi.fh.UncompressedSize)
}
func (fi headerFileInfo) IsDir() bool { return fi.Mode().IsDir() }
func (fi headerFileInfo) ModTime() time.Time { return fi.fh.ModTime() }
func (fi headerFileInfo) Mode() os.FileMode { return fi.fh.Mode() }
@ -78,25 +108,27 @@ func (fi headerFileInfo) Sys() interface{} { return fi.fh }
// os.FileInfo.
func FileInfoHeader(fi os.FileInfo) (*FileHeader, error) {
size := fi.Size()
if size > (1<<32 - 1) {
return nil, errors.New("zip: file over 4GB")
}
fh := &FileHeader{
Name: fi.Name(),
UncompressedSize: uint32(size),
Name: fi.Name(),
UncompressedSize64: uint64(size),
}
fh.SetModTime(fi.ModTime())
fh.SetMode(fi.Mode())
if fh.UncompressedSize64 > uint32max {
fh.UncompressedSize = uint32max
} else {
fh.UncompressedSize = uint32(fh.UncompressedSize64)
}
return fh, nil
}
type directoryEnd struct {
diskNbr uint16 // unused
dirDiskNbr uint16 // unused
dirRecordsThisDisk uint16 // unused
directoryRecords uint16
directorySize uint32
directoryOffset uint32 // relative to file
diskNbr uint32 // unused
dirDiskNbr uint32 // unused
dirRecordsThisDisk uint64 // unused
directoryRecords uint64
directorySize uint64
directoryOffset uint64 // relative to file
commentLen uint16
comment string
}
@ -190,6 +222,11 @@ func (h *FileHeader) SetMode(mode os.FileMode) {
}
}
// isZip64 returns true if the file size exceeds the 32 bit limit
func (fh *FileHeader) isZip64() bool {
return fh.CompressedSize64 > uint32max || fh.UncompressedSize64 > uint32max
}
func msdosModeToFileMode(m uint32) (mode os.FileMode) {
if m&msdosDir != 0 {
mode = os.ModeDir | 0777