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author | Ben Cheng <bccheng@google.com> | 2013-03-28 11:14:20 -0700 |
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committer | Ben Cheng <bccheng@google.com> | 2013-03-28 12:40:33 -0700 |
commit | af0c51ac87ab2a87caa03fa108f0d164987a2764 (patch) | |
tree | 4b8b470f7c5b69642fdab8d0aa1fbc148d02196b /gcc-4.8/libgo/go/archive/zip/writer.go | |
parent | d87cae247d39ebf4f5a6bf25c932a14d2fdb9384 (diff) | |
download | toolchain_gcc-af0c51ac87ab2a87caa03fa108f0d164987a2764.tar.gz toolchain_gcc-af0c51ac87ab2a87caa03fa108f0d164987a2764.tar.bz2 toolchain_gcc-af0c51ac87ab2a87caa03fa108f0d164987a2764.zip |
[GCC 4.8] Initial check-in of GCC 4.8.0
Change-Id: I0719d8a6d0f69b367a6ab6f10eb75622dbf12771
Diffstat (limited to 'gcc-4.8/libgo/go/archive/zip/writer.go')
-rw-r--r-- | gcc-4.8/libgo/go/archive/zip/writer.go | 352 |
1 files changed, 352 insertions, 0 deletions
diff --git a/gcc-4.8/libgo/go/archive/zip/writer.go b/gcc-4.8/libgo/go/archive/zip/writer.go new file mode 100644 index 000000000..4c696e152 --- /dev/null +++ b/gcc-4.8/libgo/go/archive/zip/writer.go @@ -0,0 +1,352 @@ +// Copyright 2011 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 zip + +import ( + "bufio" + "compress/flate" + "encoding/binary" + "errors" + "hash" + "hash/crc32" + "io" +) + +// TODO(adg): support zip file comments +// TODO(adg): support specifying deflate level + +// Writer implements a zip file writer. +type Writer struct { + cw *countWriter + dir []*header + last *fileWriter + closed bool +} + +type header struct { + *FileHeader + offset uint64 +} + +// NewWriter returns a new Writer writing a zip file to w. +func NewWriter(w io.Writer) *Writer { + return &Writer{cw: &countWriter{w: bufio.NewWriter(w)}} +} + +// Close finishes writing the zip file by writing the central directory. +// It does not (and can not) close the underlying writer. +func (w *Writer) Close() error { + if w.last != nil && !w.last.closed { + if err := w.last.close(); err != nil { + return err + } + w.last = nil + } + if w.closed { + return errors.New("zip: writer closed twice") + } + w.closed = true + + // write central directory + start := w.cw.count + for _, h := range w.dir { + var buf [directoryHeaderLen]byte + b := writeBuf(buf[:]) + b.uint32(uint32(directoryHeaderSignature)) + b.uint16(h.CreatorVersion) + b.uint16(h.ReaderVersion) + b.uint16(h.Flags) + b.uint16(h.Method) + b.uint16(h.ModifiedTime) + b.uint16(h.ModifiedDate) + b.uint32(h.CRC32) + if h.isZip64() || h.offset > uint32max { + // the file needs a zip64 header. store maxint in both + // 32 bit size fields (and offset later) to signal that the + // zip64 extra header should be used. + b.uint32(uint32max) // compressed size + b.uint32(uint32max) // uncompressed size + + // append a zip64 extra block to Extra + var buf [28]byte // 2x uint16 + 3x uint64 + eb := writeBuf(buf[:]) + eb.uint16(zip64ExtraId) + eb.uint16(24) // size = 3x uint64 + eb.uint64(h.UncompressedSize64) + eb.uint64(h.CompressedSize64) + eb.uint64(h.offset) + h.Extra = append(h.Extra, buf[:]...) + } else { + b.uint32(h.CompressedSize) + b.uint32(h.UncompressedSize) + } + b.uint16(uint16(len(h.Name))) + b.uint16(uint16(len(h.Extra))) + b.uint16(uint16(len(h.Comment))) + b = b[4:] // skip disk number start and internal file attr (2x uint16) + b.uint32(h.ExternalAttrs) + if h.offset > uint32max { + b.uint32(uint32max) + } else { + b.uint32(uint32(h.offset)) + } + if _, err := w.cw.Write(buf[:]); err != nil { + return err + } + if _, err := io.WriteString(w.cw, h.Name); err != nil { + return err + } + if _, err := w.cw.Write(h.Extra); err != nil { + return err + } + if _, err := io.WriteString(w.cw, h.Comment); err != nil { + return err + } + } + end := w.cw.count + + records := uint64(len(w.dir)) + size := uint64(end - start) + offset := uint64(start) + + if records > uint16max || size > uint32max || offset > uint32max { + var buf [directory64EndLen + directory64LocLen]byte + b := writeBuf(buf[:]) + + // zip64 end of central directory record + b.uint32(directory64EndSignature) + b.uint64(directory64EndLen) + b.uint16(zipVersion45) // version made by + b.uint16(zipVersion45) // version needed to extract + b.uint32(0) // number of this disk + b.uint32(0) // number of the disk with the start of the central directory + b.uint64(records) // total number of entries in the central directory on this disk + b.uint64(records) // total number of entries in the central directory + b.uint64(size) // size of the central directory + b.uint64(offset) // offset of start of central directory with respect to the starting disk number + + // zip64 end of central directory locator + b.uint32(directory64LocSignature) + b.uint32(0) // number of the disk with the start of the zip64 end of central directory + b.uint64(uint64(end)) // relative offset of the zip64 end of central directory record + b.uint32(1) // total number of disks + + if _, err := w.cw.Write(buf[:]); err != nil { + return err + } + + // store max values in the regular end record to signal that + // that the zip64 values should be used instead + records = uint16max + size = uint32max + offset = uint32max + } + + // write end record + var buf [directoryEndLen]byte + b := writeBuf(buf[:]) + b.uint32(uint32(directoryEndSignature)) + b = b[4:] // skip over disk number and first disk number (2x uint16) + b.uint16(uint16(records)) // number of entries this disk + b.uint16(uint16(records)) // number of entries total + b.uint32(uint32(size)) // size of directory + b.uint32(uint32(offset)) // start of directory + // skipped size of comment (always zero) + if _, err := w.cw.Write(buf[:]); err != nil { + return err + } + + return w.cw.w.(*bufio.Writer).Flush() +} + +// Create adds a file to the zip file using the provided name. +// It returns a Writer to which the file contents should be written. +// The file's contents must be written to the io.Writer before the next +// call to Create, CreateHeader, or Close. +func (w *Writer) Create(name string) (io.Writer, error) { + header := &FileHeader{ + Name: name, + Method: Deflate, + } + return w.CreateHeader(header) +} + +// CreateHeader adds a file to the zip file using the provided FileHeader +// for the file metadata. +// It returns a Writer to which the file contents should be written. +// The file's contents must be written to the io.Writer before the next +// call to Create, CreateHeader, or Close. +func (w *Writer) CreateHeader(fh *FileHeader) (io.Writer, error) { + if w.last != nil && !w.last.closed { + if err := w.last.close(); err != nil { + return nil, err + } + } + + fh.Flags |= 0x8 // we will write a data descriptor + + fh.CreatorVersion = fh.CreatorVersion&0xff00 | zipVersion20 // preserve compatibility byte + fh.ReaderVersion = zipVersion20 + + fw := &fileWriter{ + zipw: w.cw, + compCount: &countWriter{w: w.cw}, + crc32: crc32.NewIEEE(), + } + switch fh.Method { + case Store: + fw.comp = nopCloser{fw.compCount} + case Deflate: + var err error + fw.comp, err = flate.NewWriter(fw.compCount, 5) + if err != nil { + return nil, err + } + default: + return nil, ErrAlgorithm + } + fw.rawCount = &countWriter{w: fw.comp} + + h := &header{ + FileHeader: fh, + offset: uint64(w.cw.count), + } + w.dir = append(w.dir, h) + fw.header = h + + if err := writeHeader(w.cw, fh); err != nil { + return nil, err + } + + w.last = fw + return fw, nil +} + +func writeHeader(w io.Writer, h *FileHeader) error { + var buf [fileHeaderLen]byte + b := writeBuf(buf[:]) + b.uint32(uint32(fileHeaderSignature)) + b.uint16(h.ReaderVersion) + b.uint16(h.Flags) + b.uint16(h.Method) + b.uint16(h.ModifiedTime) + b.uint16(h.ModifiedDate) + b.uint32(0) // since we are writing a data descriptor crc32, + b.uint32(0) // compressed size, + b.uint32(0) // and uncompressed size should be zero + b.uint16(uint16(len(h.Name))) + b.uint16(uint16(len(h.Extra))) + if _, err := w.Write(buf[:]); err != nil { + return err + } + if _, err := io.WriteString(w, h.Name); err != nil { + return err + } + _, err := w.Write(h.Extra) + return err +} + +type fileWriter struct { + *header + zipw io.Writer + rawCount *countWriter + comp io.WriteCloser + compCount *countWriter + crc32 hash.Hash32 + closed bool +} + +func (w *fileWriter) Write(p []byte) (int, error) { + if w.closed { + return 0, errors.New("zip: write to closed file") + } + w.crc32.Write(p) + return w.rawCount.Write(p) +} + +func (w *fileWriter) close() error { + if w.closed { + return errors.New("zip: file closed twice") + } + w.closed = true + if err := w.comp.Close(); err != nil { + return err + } + + // update FileHeader + fh := w.header.FileHeader + fh.CRC32 = w.crc32.Sum32() + fh.CompressedSize64 = uint64(w.compCount.count) + fh.UncompressedSize64 = uint64(w.rawCount.count) + + if fh.isZip64() { + fh.CompressedSize = uint32max + fh.UncompressedSize = uint32max + fh.ReaderVersion = zipVersion45 // requires 4.5 - File uses ZIP64 format extensions + } else { + fh.CompressedSize = uint32(fh.CompressedSize64) + fh.UncompressedSize = uint32(fh.UncompressedSize64) + } + + // Write data descriptor. This is more complicated than one would + // think, see e.g. comments in zipfile.c:putextended() and + // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7073588. + // The approach here is to write 8 byte sizes if needed without + // adding a zip64 extra in the local header (too late anyway). + var buf []byte + if fh.isZip64() { + buf = make([]byte, dataDescriptor64Len) + } else { + buf = make([]byte, dataDescriptorLen) + } + b := writeBuf(buf) + b.uint32(dataDescriptorSignature) // de-facto standard, required by OS X + b.uint32(fh.CRC32) + if fh.isZip64() { + b.uint64(fh.CompressedSize64) + b.uint64(fh.UncompressedSize64) + } else { + b.uint32(fh.CompressedSize) + b.uint32(fh.UncompressedSize) + } + _, err := w.zipw.Write(buf) + return err +} + +type countWriter struct { + w io.Writer + count int64 +} + +func (w *countWriter) Write(p []byte) (int, error) { + n, err := w.w.Write(p) + w.count += int64(n) + return n, err +} + +type nopCloser struct { + io.Writer +} + +func (w nopCloser) Close() error { + return nil +} + +type writeBuf []byte + +func (b *writeBuf) uint16(v uint16) { + binary.LittleEndian.PutUint16(*b, v) + *b = (*b)[2:] +} + +func (b *writeBuf) uint32(v uint32) { + binary.LittleEndian.PutUint32(*b, v) + *b = (*b)[4:] +} + +func (b *writeBuf) uint64(v uint64) { + binary.LittleEndian.PutUint64(*b, v) + *b = (*b)[8:] +} |