Skip to content

G
golang
Commit d8efcdcd authored by Ian Lance Taylor's avatar Ian Lance Taylor
Browse files
Options

These files were moved to encoding/base64. The directory was 

already removed from the Makefile.

R=rsc
http://go/go-review/1017006
parent 35ace1d1
Hide whitespace changes
Inline Side-by-side
Showing with 0 additions and 546 deletions
src/pkg/base64/Makefile deleted 100644 → 0
View file @ 35ace1d1
# 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.
include $(GOROOT)/src/Make.$(GOARCH)
TARG=base64
GOFILES=\
base64.go\
include $(GOROOT)/src/Make.pkg
src/pkg/base64/base64.go deleted 100644 → 0
View file @ 35ace1d1
// 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 base64 implements base64 encoding as specified by RFC 4648.
package base64
import (
"bytes";
"io";
"os";
"strconv";
)
/*
* Encodings
*/
// An Encoding is a radix 64 encoding/decoding scheme, defined by a
// 64-character alphabet. The most common encoding is the "base64"
// encoding defined in RFC 4648 and used in MIME (RFC 2045) and PEM
// (RFC 1421). RFC 4648 also defines an alternate encoding, which is
// the standard encoding with - and _ substituted for + and /.
type Encoding struct {
encode string;
decodeMap [256]byte;
}
const encodeStd = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
const encodeURL = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"
// NewEncoding returns a new Encoding defined by the given alphabet,
// which must be a 64-byte string.
func NewEncoding(encoder string) *Encoding {
e := new(Encoding);
e.encode = encoder;
for i := 0; i < len(e.decodeMap); i++ {
e.decodeMap[i] = 0xFF;
}
for i := 0; i < len(encoder); i++ {
e.decodeMap[encoder[i]] = byte(i);
}
return e;
}
// StdEncoding is the standard base64 encoding, as defined in
// RFC 4648.
var StdEncoding = NewEncoding(encodeStd)
// URLEncoding is the alternate base64 encoding defined in RFC 4648.
// It is typically used in URLs and file names.
var URLEncoding = NewEncoding(encodeURL)
/*
* Encoder
*/
// Encode encodes src using the encoding enc, writing
// EncodedLen(len(src)) bytes to dst.
//
// The encoding pads the output to a multiple of 4 bytes,
// so Encode is not appropriate for use on individual blocks
// of a large data stream. Use NewEncoder() instead.
func (enc *Encoding) Encode(src, dst []byte) {
if len(src) == 0 {
return;
}
for len(src) > 0 {
dst[0] = 0;
dst[1] = 0;
dst[2] = 0;
dst[3] = 0;
// Unpack 4x 6-bit source blocks into a 4 byte
// destination quantum
switch len(src) {
default:
dst[3] |= src[2]&0x3F;
dst[2] |= src[2]>>6;
fallthrough;
case 2:
dst[2] |= (src[1]<<2)&0x3F;
dst[1] |= src[1]>>4;
fallthrough;
case 1:
dst[1] |= (src[0]<<4)&0x3F;
dst[0] |= src[0]>>2;
}
// Encode 6-bit blocks using the base64 alphabet
for j := 0; j < 4; j++ {
dst[j] = enc.encode[dst[j]];
}
// Pad the final quantum
if len(src) < 3 {
dst[3] = '=';
if len(src) < 2 {
dst[2] = '=';
}
break;
}
src = src[3:len(src)];
dst = dst[4:len(dst)];
}
}
type encoder struct {
err os.Error;
enc *Encoding;
w io.Writer;
buf [3]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 os.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 < 3; i++ {
e.buf[e.nbuf] = p[i];
e.nbuf++;
}
n += i;
p = p[i:len(p)];
if e.nbuf < 3 {
return;
}
e.enc.Encode(&e.buf, &e.out);
if _, e.err = e.w.Write(e.out[0:4]); e.err != nil {
return n, e.err;
}
e.nbuf = 0;
}
// Large interior chunks.
for len(p) >= 3 {
nn := len(e.out)/4*3;
if nn > len(p) {
nn = len(p);
}
nn -= nn%3;
if nn > 0 {
e.enc.Encode(p[0:nn], &e.out);
if _, e.err = e.w.Write(e.out[0 : nn/3*4]); e.err != nil {
return n, e.err;
}
}
n += nn;
p = p[nn:len(p)];
}
// 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() os.Error {
// If there's anything left in the buffer, flush it out
if e.err == nil && e.nbuf > 0 {
e.enc.Encode(e.buf[0 : e.nbuf], &e.out);
e.nbuf = 0;
_, e.err = e.w.Write(e.out[0:4]);
}
return e.err;
}
// NewEncoder returns a new base64 stream encoder. Data written to
// the returned writer will be encoded using enc and then written to w.
// Base64 encodings operate in 4-byte blocks; when finished
// writing, the caller must Close the returned encoder to flush any
// partially written blocks.
func NewEncoder(enc *Encoding, w io.Writer) io.WriteCloser {
return &encoder{enc: enc, w: w};
}
// EncodedLen returns the length in bytes of the base64 encoding
// of an input buffer of length n.
func (enc *Encoding) EncodedLen(n int) int {
return (n+2)/3*4;
}
/*
* Decoder
*/
type CorruptInputError int64
func (e CorruptInputError) String() string {
return "illegal base64 data at input byte" + strconv.Itoa64(int64(e));
}
// decode is like Decode but returns an additional 'end' value, which
// indicates if end-of-message padding was encountered and thus any
// additional data is an error. decode also assumes len(src)%4==0,
// since it is meant for internal use.
func (enc *Encoding) decode(src, dst []byte) (n int, end bool, err os.Error) {
for i := 0; i < len(src)/4 && !end; i++ {
// Decode quantum using the base64 alphabet
var dbuf [4]byte;
dlen := 4;
dbufloop:
for j := 0; j < 4; j++ {
in := src[i*4 + j];
if in == '=' && j >= 2 && i == len(src)/4 - 1 {
// We've reached the end and there's
// padding
if src[i*4 + 3] != '=' {
return n, false, CorruptInputError(i*4 + 2);
}
dlen = j;
end = true;
break dbufloop;
}
dbuf[j] = enc.decodeMap[in];
if dbuf[j] == 0xFF {
return n, false, CorruptInputError(i*4 + j);
}
}
// Pack 4x 6-bit source blocks into 3 byte destination
// quantum
switch dlen {
case 4:
dst[i*3 + 2] = dbuf[2]<<6 | dbuf[3];
fallthrough;
case 3:
dst[i*3 + 1] = dbuf[1]<<4 | dbuf[2]>>2;
fallthrough;
case 2:
dst[i*3 + 0] = dbuf[0]<<2 | dbuf[1]>>4;
}
n += dlen-1;
}
return n, end, nil;
}
// Decode decodes src using the encoding enc. It writes at most
// DecodedLen(len(src)) bytes to dst and returns the number of bytes
// written. If src contains invalid base64 data, it will return the
// number of bytes successfully written and CorruptInputError.
func (enc *Encoding) Decode(src, dst []byte) (n int, err os.Error) {
if len(src)%4 != 0 {
return 0, CorruptInputError(len(src)/4*4);
}
n, _, err = enc.decode(src, dst);
return;
}
type decoder struct {
err os.Error;
enc *Encoding;
r io.Reader;
end bool; // saw end of message
buf [1024]byte; // leftover input
nbuf int;
out []byte; // leftover decoded output
outbuf [1024/4*3]byte;
}
func (d *decoder) Read(p []byte) (n int, err os.Error) {
if d.err != nil {
return 0, d.err;
}
// Use leftover decoded output from last read.
if len(d.out) > 0 {
n = bytes.Copy(p, d.out);
d.out = d.out[n:len(d.out)];
return n, nil;
}
// Read a chunk.
nn := len(p)/3*4;
if nn < 4 {
nn = 4;
}
if nn > len(d.buf) {
nn = len(d.buf);
}
nn, d.err = io.ReadAtLeast(d.r, d.buf[d.nbuf : nn], 4 - d.nbuf);
d.nbuf += nn;
if d.nbuf < 4 {
return 0, d.err;
}
// Decode chunk into p, or d.out and then p if p is too small.
nr := d.nbuf / 4 * 4;
nw := d.nbuf / 4 * 3;
if nw > len(p) {
nw, d.end, d.err = d.enc.decode(d.buf[0:nr], &d.outbuf);
d.out = d.outbuf[0:nw];
n = bytes.Copy(p, d.out);
d.out = d.out[n:len(d.out)];
} else {
n, d.end, d.err = d.enc.decode(d.buf[0:nr], p);
}
d.nbuf -= nr;
for i := 0; i < d.nbuf; i++ {
d.buf[i] = d.buf[i+nr];
}
if d.err == nil {
d.err = err;
}
return n, d.err;
}
// NewDecoder constructs a new base64 stream decoder.
func NewDecoder(enc *Encoding, r io.Reader) io.Reader {
return &decoder{enc: enc, r: r};
}
// DecodeLen returns the maximum length in bytes of the decoded data
// corresponding to n bytes of base64-encoded data.
func (enc *Encoding) DecodedLen(n int) int {
return n/4*3;
}
src/pkg/base64/base64_test.go deleted 100644 → 0
View file @ 35ace1d1
// 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 base64
import (
"bytes";
"io";
"os";
"reflect";
"strings";
"testing";
)
type testpair struct {
decoded, encoded string;
}
var pairs = []testpair{
// RFC 3548 examples
testpair{"\x14\xfb\x9c\x03\xd9\x7e", "FPucA9l+"},
testpair{"\x14\xfb\x9c\x03\xd9", "FPucA9k="},
testpair{"\x14\xfb\x9c\x03", "FPucAw=="},
// RFC 4648 examples
testpair{"", ""},
testpair{"f", "Zg=="},
testpair{"fo", "Zm8="},
testpair{"foo", "Zm9v"},
testpair{"foob", "Zm9vYg=="},
testpair{"fooba", "Zm9vYmE="},
testpair{"foobar", "Zm9vYmFy"},
// Wikipedia examples
testpair{"sure.", "c3VyZS4="},
testpair{"sure", "c3VyZQ=="},
testpair{"sur", "c3Vy"},
testpair{"su", "c3U="},
testpair{"leasure.", "bGVhc3VyZS4="},
testpair{"easure.", "ZWFzdXJlLg=="},
testpair{"asure.", "YXN1cmUu"},
testpair{"sure.", "c3VyZS4="},
}
var bigtest = testpair{
"Twas brillig, and the slithy toves",
"VHdhcyBicmlsbGlnLCBhbmQgdGhlIHNsaXRoeSB0b3Zlcw==",
}
func testEqual(t *testing.T, msg string, args ...) bool {
v := reflect.NewValue(args).(*reflect.StructValue);
v1 := v.Field(v.NumField() - 2);
v2 := v.Field(v.NumField() - 1);
if v1.Interface() != v2.Interface() {
t.Errorf(msg, args);
return false;
}
return true;
}
func TestEncode(t *testing.T) {
for _, p := range pairs {
buf := make([]byte, StdEncoding.EncodedLen(len(p.decoded)));
StdEncoding.Encode(strings.Bytes(p.decoded), buf);
testEqual(t, "Encode(%q) = %q, want %q", p.decoded, string(buf), p.encoded);
}
}
func TestEncoder(t *testing.T) {
for _, p := range pairs {
bb := &bytes.Buffer{};
encoder := NewEncoder(StdEncoding, bb);
encoder.Write(strings.Bytes(p.decoded));
encoder.Close();
testEqual(t, "Encode(%q) = %q, want %q", p.decoded, bb.String(), p.encoded);
}
}
func TestEncoderBuffering(t *testing.T) {
input := strings.Bytes(bigtest.decoded);
for bs := 1; bs <= 12; bs++ {
bb := &bytes.Buffer{};
encoder := NewEncoder(StdEncoding, 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, os.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, os.Error(nil));
testEqual(t, "Encoding/%d of %q = %q, want %q", bs, bigtest.decoded, bb.String(), bigtest.encoded);
}
}
func TestDecode(t *testing.T) {
for _, p := range pairs {
dbuf := make([]byte, StdEncoding.DecodedLen(len(p.encoded)));
count, end, err := StdEncoding.decode(strings.Bytes(p.encoded), dbuf);
testEqual(t, "Decode(%q) = error %v, want %v", p.encoded, err, os.Error(nil));
testEqual(t, "Decode(%q) = length %v, want %v", p.encoded, count, len(p.decoded));
if len(p.encoded) > 0 {
testEqual(t, "Decode(%q) = end %v, want %v", p.encoded, end, (p.encoded[len(p.encoded)-1] == '='));
}
testEqual(t, "Decode(%q) = %q, want %q", p.encoded, string(dbuf[0:count]), p.decoded);
}
}
func TestDecoder(t *testing.T) {
for _, p := range pairs {
decoder := NewDecoder(StdEncoding, bytes.NewBufferString(p.encoded));
dbuf := make([]byte, StdEncoding.DecodedLen(len(p.encoded)));
count, err := decoder.Read(dbuf);
if err != nil && err != os.EOF {
t.Fatal("Read failed", err);
}
testEqual(t, "Read from %q = length %v, want %v", p.encoded, count, len(p.decoded));
testEqual(t, "Decoding of %q = %q, want %q", p.encoded, string(dbuf[0:count]), p.decoded);
if err != os.EOF {
count, err = decoder.Read(dbuf);
}
testEqual(t, "Read from %q = %v, want %v", p.encoded, err, os.EOF);
}
}
func TestDecoderBuffering(t *testing.T) {
for bs := 1; bs <= 12; bs++ {
decoder := NewDecoder(StdEncoding, bytes.NewBufferString(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, os.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{
corrupt{"!!!!", 0},
corrupt{"x===", 1},
corrupt{"AA=A", 2},
corrupt{"AAA=AAAA", 3},
corrupt{"AAAAA", 4},
corrupt{"AAAAAA", 4},
};
for _, e := range examples {
dbuf := make([]byte, StdEncoding.DecodedLen(len(e.e)));
_, err := StdEncoding.Decode(strings.Bytes(e.e), dbuf);
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(StdEncoding, 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 := io.ReadAll(NewDecoder(StdEncoding, 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);
}
}
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment