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Diffstat (limited to 'src/pkg/encoding/ascii85')
-rw-r--r--src/pkg/encoding/ascii85/ascii85.go311
-rw-r--r--src/pkg/encoding/ascii85/ascii85_test.go210
2 files changed, 0 insertions, 521 deletions
diff --git a/src/pkg/encoding/ascii85/ascii85.go b/src/pkg/encoding/ascii85/ascii85.go
deleted file mode 100644
index 60da304b5..000000000
--- a/src/pkg/encoding/ascii85/ascii85.go
+++ /dev/null
@@ -1,311 +0,0 @@
-// 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 ascii85 implements the ascii85 data encoding
-// as used in the btoa tool and Adobe's PostScript and PDF document formats.
-package ascii85
-
-import (
- "io"
- "strconv"
-)
-
-/*
- * Encoder
- */
-
-// Encode encodes src into at most MaxEncodedLen(len(src))
-// bytes of dst, returning the actual number of bytes written.
-//
-// The encoding handles 4-byte chunks, using a special encoding
-// for the last fragment, so Encode is not appropriate for use on
-// individual blocks of a large data stream. Use NewEncoder() instead.
-//
-// Often, ascii85-encoded data is wrapped in <~ and ~> symbols.
-// Encode does not add these.
-func Encode(dst, src []byte) int {
- if len(src) == 0 {
- return 0
- }
-
- n := 0
- for len(src) > 0 {
- dst[0] = 0
- dst[1] = 0
- dst[2] = 0
- dst[3] = 0
- dst[4] = 0
-
- // Unpack 4 bytes into uint32 to repack into base 85 5-byte.
- var v uint32
- switch len(src) {
- default:
- v |= uint32(src[3])
- fallthrough
- case 3:
- v |= uint32(src[2]) << 8
- fallthrough
- case 2:
- v |= uint32(src[1]) << 16
- fallthrough
- case 1:
- v |= uint32(src[0]) << 24
- }
-
- // Special case: zero (!!!!!) shortens to z.
- if v == 0 && len(src) >= 4 {
- dst[0] = 'z'
- dst = dst[1:]
- src = src[4:]
- n++
- continue
- }
-
- // Otherwise, 5 base 85 digits starting at !.
- for i := 4; i >= 0; i-- {
- dst[i] = '!' + byte(v%85)
- v /= 85
- }
-
- // If src was short, discard the low destination bytes.
- m := 5
- if len(src) < 4 {
- m -= 4 - len(src)
- src = nil
- } else {
- src = src[4:]
- }
- dst = dst[m:]
- n += m
- }
- return n
-}
-
-// MaxEncodedLen returns the maximum length of an encoding of n source bytes.
-func MaxEncodedLen(n int) int { return (n + 3) / 4 * 5 }
-
-// NewEncoder returns a new ascii85 stream encoder. Data written to
-// the returned writer will be encoded and then written to w.
-// Ascii85 encodings operate in 32-bit blocks; when finished
-// writing, the caller must Close the returned encoder to flush any
-// trailing partial block.
-func NewEncoder(w io.Writer) io.WriteCloser { return &encoder{w: w} }
-
-type encoder struct {
- err error
- w io.Writer
- buf [4]byte // buffered data waiting to be encoded
- nbuf int // number of bytes in buf
- out [1024]byte // output buffer
-}
-
-func (e *encoder) Write(p []byte) (n int, err error) {
- if e.err != nil {
- return 0, e.err
- }
-
- // Leading fringe.
- if e.nbuf > 0 {
- var i int
- for i = 0; i < len(p) && e.nbuf < 4; i++ {
- e.buf[e.nbuf] = p[i]
- e.nbuf++
- }
- n += i
- p = p[i:]
- if e.nbuf < 4 {
- return
- }
- nout := Encode(e.out[0:], e.buf[0:])
- if _, e.err = e.w.Write(e.out[0:nout]); e.err != nil {
- return n, e.err
- }
- e.nbuf = 0
- }
-
- // Large interior chunks.
- for len(p) >= 4 {
- nn := len(e.out) / 5 * 4
- if nn > len(p) {
- nn = len(p)
- }
- nn -= nn % 4
- if nn > 0 {
- nout := Encode(e.out[0:], p[0:nn])
- if _, e.err = e.w.Write(e.out[0:nout]); e.err != nil {
- return n, e.err
- }
- }
- n += nn
- p = p[nn:]
- }
-
- // Trailing fringe.
- for i := 0; i < len(p); i++ {
- e.buf[i] = p[i]
- }
- e.nbuf = len(p)
- n += len(p)
- return
-}
-
-// Close flushes any pending output from the encoder.
-// It is an error to call Write after calling Close.
-func (e *encoder) Close() error {
- // If there's anything left in the buffer, flush it out
- if e.err == nil && e.nbuf > 0 {
- nout := Encode(e.out[0:], e.buf[0:e.nbuf])
- e.nbuf = 0
- _, e.err = e.w.Write(e.out[0:nout])
- }
- return e.err
-}
-
-/*
- * Decoder
- */
-
-type CorruptInputError int64
-
-func (e CorruptInputError) Error() string {
- return "illegal ascii85 data at input byte " + strconv.FormatInt(int64(e), 10)
-}
-
-// Decode decodes src into dst, returning both the number
-// of bytes written to dst and the number consumed from src.
-// If src contains invalid ascii85 data, Decode will return the
-// number of bytes successfully written and a CorruptInputError.
-// Decode ignores space and control characters in src.
-// Often, ascii85-encoded data is wrapped in <~ and ~> symbols.
-// Decode expects these to have been stripped by the caller.
-//
-// If flush is true, Decode assumes that src represents the
-// end of the input stream and processes it completely rather
-// than wait for the completion of another 32-bit block.
-//
-// NewDecoder wraps an io.Reader interface around Decode.
-//
-func Decode(dst, src []byte, flush bool) (ndst, nsrc int, err error) {
- var v uint32
- var nb int
- for i, b := range src {
- if len(dst)-ndst < 4 {
- return
- }
- switch {
- case b <= ' ':
- continue
- case b == 'z' && nb == 0:
- nb = 5
- v = 0
- case '!' <= b && b <= 'u':
- v = v*85 + uint32(b-'!')
- nb++
- default:
- return 0, 0, CorruptInputError(i)
- }
- if nb == 5 {
- nsrc = i + 1
- dst[ndst] = byte(v >> 24)
- dst[ndst+1] = byte(v >> 16)
- dst[ndst+2] = byte(v >> 8)
- dst[ndst+3] = byte(v)
- ndst += 4
- nb = 0
- v = 0
- }
- }
- if flush {
- nsrc = len(src)
- if nb > 0 {
- // The number of output bytes in the last fragment
- // is the number of leftover input bytes - 1:
- // the extra byte provides enough bits to cover
- // the inefficiency of the encoding for the block.
- if nb == 1 {
- return 0, 0, CorruptInputError(len(src))
- }
- for i := nb; i < 5; i++ {
- // The short encoding truncated the output value.
- // We have to assume the worst case values (digit 84)
- // in order to ensure that the top bits are correct.
- v = v*85 + 84
- }
- for i := 0; i < nb-1; i++ {
- dst[ndst] = byte(v >> 24)
- v <<= 8
- ndst++
- }
- }
- }
- return
-}
-
-// NewDecoder constructs a new ascii85 stream decoder.
-func NewDecoder(r io.Reader) io.Reader { return &decoder{r: r} }
-
-type decoder struct {
- err error
- readErr error
- r io.Reader
- end bool // saw end of message
- buf [1024]byte // leftover input
- nbuf int
- out []byte // leftover decoded output
- outbuf [1024]byte
-}
-
-func (d *decoder) Read(p []byte) (n int, err error) {
- if len(p) == 0 {
- return 0, nil
- }
- if d.err != nil {
- return 0, d.err
- }
-
- for {
- // Copy leftover output from last decode.
- if len(d.out) > 0 {
- n = copy(p, d.out)
- d.out = d.out[n:]
- return
- }
-
- // Decode leftover input from last read.
- var nn, nsrc, ndst int
- if d.nbuf > 0 {
- ndst, nsrc, d.err = Decode(d.outbuf[0:], d.buf[0:d.nbuf], d.readErr != nil)
- if ndst > 0 {
- d.out = d.outbuf[0:ndst]
- d.nbuf = copy(d.buf[0:], d.buf[nsrc:d.nbuf])
- continue // copy out and return
- }
- if ndst == 0 && d.err == nil {
- // Special case: input buffer is mostly filled with non-data bytes.
- // Filter out such bytes to make room for more input.
- off := 0
- for i := 0; i < d.nbuf; i++ {
- if d.buf[i] > ' ' {
- d.buf[off] = d.buf[i]
- off++
- }
- }
- d.nbuf = off
- }
- }
-
- // Out of input, out of decoded output. Check errors.
- if d.err != nil {
- return 0, d.err
- }
- if d.readErr != nil {
- d.err = d.readErr
- return 0, d.err
- }
-
- // Read more data.
- nn, d.readErr = d.r.Read(d.buf[d.nbuf:])
- d.nbuf += nn
- }
-}
diff --git a/src/pkg/encoding/ascii85/ascii85_test.go b/src/pkg/encoding/ascii85/ascii85_test.go
deleted file mode 100644
index aad199b4f..000000000
--- a/src/pkg/encoding/ascii85/ascii85_test.go
+++ /dev/null
@@ -1,210 +0,0 @@
-// 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 ascii85
-
-import (
- "bytes"
- "io"
- "io/ioutil"
- "strings"
- "testing"
-)
-
-type testpair struct {
- decoded, encoded string
-}
-
-var pairs = []testpair{
- // Encode returns 0 when len(src) is 0
- {
- "",
- "",
- },
- // Wikipedia example
- {
- "Man is distinguished, not only by his reason, but by this singular passion from " +
- "other animals, which is a lust of the mind, that by a perseverance of delight in " +
- "the continued and indefatigable generation of knowledge, exceeds the short " +
- "vehemence of any carnal pleasure.",
- "9jqo^BlbD-BleB1DJ+*+F(f,q/0JhKF<GL>Cj@.4Gp$d7F!,L7@<6@)/0JDEF<G%<+EV:2F!,\n" +
- "O<DJ+*.@<*K0@<6L(Df-\\0Ec5e;DffZ(EZee.Bl.9pF\"AGXBPCsi+DGm>@3BB/F*&OCAfu2/AKY\n" +
- "i(DIb:@FD,*)+C]U=@3BN#EcYf8ATD3s@q?d$AftVqCh[NqF<G:8+EV:.+Cf>-FD5W8ARlolDIa\n" +
- "l(DId<j@<?3r@:F%a+D58'ATD4$Bl@l3De:,-DJs`8ARoFb/0JMK@qB4^F!,R<AKZ&-DfTqBG%G\n" +
- ">uD.RTpAKYo'+CT/5+Cei#DII?(E,9)oF*2M7/c\n",
- },
- // Special case when shortening !!!!! to z.
- {
- "\000\000\000\000",
- "z",
- },
-}
-
-var bigtest = pairs[len(pairs)-1]
-
-func testEqual(t *testing.T, msg string, args ...interface{}) bool {
- if args[len(args)-2] != args[len(args)-1] {
- t.Errorf(msg, args...)
- return false
- }
- return true
-}
-
-func strip85(s string) string {
- t := make([]byte, len(s))
- w := 0
- for r := 0; r < len(s); r++ {
- c := s[r]
- if c > ' ' {
- t[w] = c
- w++
- }
- }
- return string(t[0:w])
-}
-
-func TestEncode(t *testing.T) {
- for _, p := range pairs {
- buf := make([]byte, MaxEncodedLen(len(p.decoded)))
- n := Encode(buf, []byte(p.decoded))
- buf = buf[0:n]
- testEqual(t, "Encode(%q) = %q, want %q", p.decoded, strip85(string(buf)), strip85(p.encoded))
- }
-}
-
-func TestEncoder(t *testing.T) {
- for _, p := range pairs {
- bb := &bytes.Buffer{}
- encoder := NewEncoder(bb)
- encoder.Write([]byte(p.decoded))
- encoder.Close()
- testEqual(t, "Encode(%q) = %q, want %q", p.decoded, strip85(bb.String()), strip85(p.encoded))
- }
-}
-
-func TestEncoderBuffering(t *testing.T) {
- input := []byte(bigtest.decoded)
- for bs := 1; bs <= 12; bs++ {
- bb := &bytes.Buffer{}
- encoder := NewEncoder(bb)
- for pos := 0; pos < len(input); pos += bs {
- end := pos + bs
- if end > len(input) {
- end = len(input)
- }
- n, err := encoder.Write(input[pos:end])
- testEqual(t, "Write(%q) gave error %v, want %v", input[pos:end], err, error(nil))
- testEqual(t, "Write(%q) gave length %v, want %v", input[pos:end], n, end-pos)
- }
- err := encoder.Close()
- testEqual(t, "Close gave error %v, want %v", err, error(nil))
- testEqual(t, "Encoding/%d of %q = %q, want %q", bs, bigtest.decoded, strip85(bb.String()), strip85(bigtest.encoded))
- }
-}
-
-func TestDecode(t *testing.T) {
- for _, p := range pairs {
- dbuf := make([]byte, 4*len(p.encoded))
- ndst, nsrc, err := Decode(dbuf, []byte(p.encoded), true)
- testEqual(t, "Decode(%q) = error %v, want %v", p.encoded, err, error(nil))
- testEqual(t, "Decode(%q) = nsrc %v, want %v", p.encoded, nsrc, len(p.encoded))
- testEqual(t, "Decode(%q) = ndst %v, want %v", p.encoded, ndst, len(p.decoded))
- testEqual(t, "Decode(%q) = %q, want %q", p.encoded, string(dbuf[0:ndst]), p.decoded)
- }
-}
-
-func TestDecoder(t *testing.T) {
- for _, p := range pairs {
- decoder := NewDecoder(strings.NewReader(p.encoded))
- dbuf, err := ioutil.ReadAll(decoder)
- if err != nil {
- t.Fatal("Read failed", err)
- }
- testEqual(t, "Read from %q = length %v, want %v", p.encoded, len(dbuf), len(p.decoded))
- testEqual(t, "Decoding of %q = %q, want %q", p.encoded, string(dbuf), p.decoded)
- if err != nil {
- testEqual(t, "Read from %q = %v, want %v", p.encoded, err, io.EOF)
- }
- }
-}
-
-func TestDecoderBuffering(t *testing.T) {
- for bs := 1; bs <= 12; bs++ {
- decoder := NewDecoder(strings.NewReader(bigtest.encoded))
- buf := make([]byte, len(bigtest.decoded)+12)
- var total int
- for total = 0; total < len(bigtest.decoded); {
- n, err := decoder.Read(buf[total : total+bs])
- testEqual(t, "Read from %q at pos %d = %d, %v, want _, %v", bigtest.encoded, total, n, err, error(nil))
- total += n
- }
- testEqual(t, "Decoding/%d of %q = %q, want %q", bs, bigtest.encoded, string(buf[0:total]), bigtest.decoded)
- }
-}
-
-func TestDecodeCorrupt(t *testing.T) {
- type corrupt struct {
- e string
- p int
- }
- examples := []corrupt{
- {"v", 0},
- {"!z!!!!!!!!!", 1},
- }
-
- for _, e := range examples {
- dbuf := make([]byte, 4*len(e.e))
- _, _, err := Decode(dbuf, []byte(e.e), true)
- switch err := err.(type) {
- case CorruptInputError:
- testEqual(t, "Corruption in %q at offset %v, want %v", e.e, int(err), e.p)
- default:
- t.Error("Decoder failed to detect corruption in", e)
- }
- }
-}
-
-func TestBig(t *testing.T) {
- n := 3*1000 + 1
- raw := make([]byte, n)
- const alpha = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
- for i := 0; i < n; i++ {
- raw[i] = alpha[i%len(alpha)]
- }
- encoded := new(bytes.Buffer)
- w := NewEncoder(encoded)
- nn, err := w.Write(raw)
- if nn != n || err != nil {
- t.Fatalf("Encoder.Write(raw) = %d, %v want %d, nil", nn, err, n)
- }
- err = w.Close()
- if err != nil {
- t.Fatalf("Encoder.Close() = %v want nil", err)
- }
- decoded, err := ioutil.ReadAll(NewDecoder(encoded))
- if err != nil {
- t.Fatalf("io.ReadAll(NewDecoder(...)): %v", err)
- }
-
- if !bytes.Equal(raw, decoded) {
- var i int
- for i = 0; i < len(decoded) && i < len(raw); i++ {
- if decoded[i] != raw[i] {
- break
- }
- }
- t.Errorf("Decode(Encode(%d-byte string)) failed at offset %d", n, i)
- }
-}
-
-func TestDecoderInternalWhitespace(t *testing.T) {
- s := strings.Repeat(" ", 2048) + "z"
- decoded, err := ioutil.ReadAll(NewDecoder(strings.NewReader(s)))
- if err != nil {
- t.Errorf("Decode gave error %v", err)
- }
- if want := []byte("\000\000\000\000"); !bytes.Equal(want, decoded) {
- t.Errorf("Decode failed: got %v, want %v", decoded, want)
- }
-}
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-29 22:30:50 +0000