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-rw-r--r--vendor/github.com/miekg/dns/vendor/golang.org/x/crypto/openpgp/packet/compressed.go123
1 files changed, 123 insertions, 0 deletions
diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/crypto/openpgp/packet/compressed.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/crypto/openpgp/packet/compressed.go
new file mode 100644
index 000000000..e8f0b5caa
--- /dev/null
+++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/crypto/openpgp/packet/compressed.go
@@ -0,0 +1,123 @@
+// 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 packet
+
+import (
+ "compress/bzip2"
+ "compress/flate"
+ "compress/zlib"
+ "golang.org/x/crypto/openpgp/errors"
+ "io"
+ "strconv"
+)
+
+// Compressed represents a compressed OpenPGP packet. The decompressed contents
+// will contain more OpenPGP packets. See RFC 4880, section 5.6.
+type Compressed struct {
+ Body io.Reader
+}
+
+const (
+ NoCompression = flate.NoCompression
+ BestSpeed = flate.BestSpeed
+ BestCompression = flate.BestCompression
+ DefaultCompression = flate.DefaultCompression
+)
+
+// CompressionConfig contains compressor configuration settings.
+type CompressionConfig struct {
+ // Level is the compression level to use. It must be set to
+ // between -1 and 9, with -1 causing the compressor to use the
+ // default compression level, 0 causing the compressor to use
+ // no compression and 1 to 9 representing increasing (better,
+ // slower) compression levels. If Level is less than -1 or
+ // more then 9, a non-nil error will be returned during
+ // encryption. See the constants above for convenient common
+ // settings for Level.
+ Level int
+}
+
+func (c *Compressed) parse(r io.Reader) error {
+ var buf [1]byte
+ _, err := readFull(r, buf[:])
+ if err != nil {
+ return err
+ }
+
+ switch buf[0] {
+ case 1:
+ c.Body = flate.NewReader(r)
+ case 2:
+ c.Body, err = zlib.NewReader(r)
+ case 3:
+ c.Body = bzip2.NewReader(r)
+ default:
+ err = errors.UnsupportedError("unknown compression algorithm: " + strconv.Itoa(int(buf[0])))
+ }
+
+ return err
+}
+
+// compressedWriterCloser represents the serialized compression stream
+// header and the compressor. Its Close() method ensures that both the
+// compressor and serialized stream header are closed. Its Write()
+// method writes to the compressor.
+type compressedWriteCloser struct {
+ sh io.Closer // Stream Header
+ c io.WriteCloser // Compressor
+}
+
+func (cwc compressedWriteCloser) Write(p []byte) (int, error) {
+ return cwc.c.Write(p)
+}
+
+func (cwc compressedWriteCloser) Close() (err error) {
+ err = cwc.c.Close()
+ if err != nil {
+ return err
+ }
+
+ return cwc.sh.Close()
+}
+
+// SerializeCompressed serializes a compressed data packet to w and
+// returns a WriteCloser to which the literal data packets themselves
+// can be written and which MUST be closed on completion. If cc is
+// nil, sensible defaults will be used to configure the compression
+// algorithm.
+func SerializeCompressed(w io.WriteCloser, algo CompressionAlgo, cc *CompressionConfig) (literaldata io.WriteCloser, err error) {
+ compressed, err := serializeStreamHeader(w, packetTypeCompressed)
+ if err != nil {
+ return
+ }
+
+ _, err = compressed.Write([]byte{uint8(algo)})
+ if err != nil {
+ return
+ }
+
+ level := DefaultCompression
+ if cc != nil {
+ level = cc.Level
+ }
+
+ var compressor io.WriteCloser
+ switch algo {
+ case CompressionZIP:
+ compressor, err = flate.NewWriter(compressed, level)
+ case CompressionZLIB:
+ compressor, err = zlib.NewWriterLevel(compressed, level)
+ default:
+ s := strconv.Itoa(int(algo))
+ err = errors.UnsupportedError("Unsupported compression algorithm: " + s)
+ }
+ if err != nil {
+ return
+ }
+
+ literaldata = compressedWriteCloser{compressed, compressor}
+
+ return
+}