build: move package sources from src/pkg to src

Preparation was in CL 134570043.
This CL contains only the effect of 'hg mv src/pkg/* src'.
For more about the move, see golang.org/s/go14nopkg.

3 files changed, 796 insertions, 0 deletions

diff --git a/src/encoding/base64/base64.go b/src/encoding/base64/base64.go
new file mode 100644
index 0000000000..ad3abe6623
--- /dev/null
+++ b/src/encoding/base64/base64.go
@@ -0,0 +1,391 @@
+// 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"
+	"strconv"
+	"strings"
+)
+
+/*
+ * 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)
+
+var removeNewlinesMapper = func(r rune) rune {
+	if r == '\r' || r == '\n' {
+		return -1
+	}
+	return r
+}
+
+/*
+ * 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(dst, src []byte) {
+	if len(src) == 0 {
+		return
+	}
+
+	for len(src) > 0 {
+		var b0, b1, b2, b3 byte
+
+		// Unpack 4x 6-bit source blocks into a 4 byte
+		// destination quantum
+		switch len(src) {
+		default:
+			b3 = src[2] & 0x3F
+			b2 = src[2] >> 6
+			fallthrough
+		case 2:
+			b2 |= (src[1] << 2) & 0x3F
+			b1 = src[1] >> 4
+			fallthrough
+		case 1:
+			b1 |= (src[0] << 4) & 0x3F
+			b0 = src[0] >> 2
+		}
+
+		// Encode 6-bit blocks using the base64 alphabet
+		dst[0] = enc.encode[b0]
+		dst[1] = enc.encode[b1]
+		dst[2] = enc.encode[b2]
+		dst[3] = enc.encode[b3]
+
+		// Pad the final quantum
+		if len(src) < 3 {
+			dst[3] = '='
+			if len(src) < 2 {
+				dst[2] = '='
+			}
+			break
+		}
+
+		src = src[3:]
+		dst = dst[4:]
+	}
+}
+
+// EncodeToString returns the base64 encoding of src.
+func (enc *Encoding) EncodeToString(src []byte) string {
+	buf := make([]byte, enc.EncodedLen(len(src)))
+	enc.Encode(buf, src)
+	return string(buf)
+}
+
+type encoder struct {
+	err  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 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:]
+		if e.nbuf < 3 {
+			return
+		}
+		e.enc.Encode(e.out[0:], e.buf[0:])
+		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
+		}
+		e.enc.Encode(e.out[0:], p[0:nn])
+		if _, e.err = e.w.Write(e.out[0 : nn/3*4]); 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 {
+		e.enc.Encode(e.out[0:], e.buf[0:e.nbuf])
+		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) Error() string {
+	return "illegal base64 data at input byte " + strconv.FormatInt(int64(e), 10)
+}
+
+// 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. This method assumes that src has been
+// stripped of all supported whitespace ('\r' and '\n').
+func (enc *Encoding) decode(dst, src []byte) (n int, end bool, err error) {
+	olen := len(src)
+	for len(src) > 0 && !end {
+		// Decode quantum using the base64 alphabet
+		var dbuf [4]byte
+		dlen := 4
+
+		for j := range dbuf {
+			if len(src) == 0 {
+				return n, false, CorruptInputError(olen - len(src) - j)
+			}
+			in := src[0]
+			src = src[1:]
+			if in == '=' {
+				// We've reached the end and there's padding
+				switch j {
+				case 0, 1:
+					// incorrect padding
+					return n, false, CorruptInputError(olen - len(src) - 1)
+				case 2:
+					// "==" is expected, the first "=" is already consumed.
+					if len(src) == 0 {
+						// not enough padding
+						return n, false, CorruptInputError(olen)
+					}
+					if src[0] != '=' {
+						// incorrect padding
+						return n, false, CorruptInputError(olen - len(src) - 1)
+					}
+					src = src[1:]
+				}
+				if len(src) > 0 {
+					// trailing garbage
+					err = CorruptInputError(olen - len(src))
+				}
+				dlen, end = j, true
+				break
+			}
+			dbuf[j] = enc.decodeMap[in]
+			if dbuf[j] == 0xFF {
+				return n, false, CorruptInputError(olen - len(src) - 1)
+			}
+		}
+
+		// Pack 4x 6-bit source blocks into 3 byte destination
+		// quantum
+		switch dlen {
+		case 4:
+			dst[2] = dbuf[2]<<6 | dbuf[3]
+			fallthrough
+		case 3:
+			dst[1] = dbuf[1]<<4 | dbuf[2]>>2
+			fallthrough
+		case 2:
+			dst[0] = dbuf[0]<<2 | dbuf[1]>>4
+		}
+		dst = dst[3:]
+		n += dlen - 1
+	}
+
+	return n, end, err
+}
+
+// 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.
+// New line characters (\r and \n) are ignored.
+func (enc *Encoding) Decode(dst, src []byte) (n int, err error) {
+	src = bytes.Map(removeNewlinesMapper, src)
+	n, _, err = enc.decode(dst, src)
+	return
+}
+
+// DecodeString returns the bytes represented by the base64 string s.
+func (enc *Encoding) DecodeString(s string) ([]byte, error) {
+	s = strings.Map(removeNewlinesMapper, s)
+	dbuf := make([]byte, enc.DecodedLen(len(s)))
+	n, _, err := enc.decode(dbuf, []byte(s))
+	return dbuf[:n], err
+}
+
+type decoder struct {
+	err    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 error) {
+	if d.err != nil {
+		return 0, d.err
+	}
+
+	// Use leftover decoded output from last read.
+	if len(d.out) > 0 {
+		n = copy(p, d.out)
+		d.out = d.out[n:]
+		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.err != nil || 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.outbuf[0:], d.buf[0:nr])
+		d.out = d.outbuf[0:nw]
+		n = copy(p, d.out)
+		d.out = d.out[n:]
+	} else {
+		n, d.end, d.err = d.enc.decode(p, d.buf[0:nr])
+	}
+	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
+}
+
+type newlineFilteringReader struct {
+	wrapped io.Reader
+}
+
+func (r *newlineFilteringReader) Read(p []byte) (int, error) {
+	n, err := r.wrapped.Read(p)
+	for n > 0 {
+		offset := 0
+		for i, b := range p[0:n] {
+			if b != '\r' && b != '\n' {
+				if i != offset {
+					p[offset] = b
+				}
+				offset++
+			}
+		}
+		if offset > 0 {
+			return offset, err
+		}
+		// Previous buffer entirely whitespace, read again
+		n, err = r.wrapped.Read(p)
+	}
+	return n, err
+}
+
+// NewDecoder constructs a new base64 stream decoder.
+func NewDecoder(enc *Encoding, r io.Reader) io.Reader {
+	return &decoder{enc: enc, r: &newlineFilteringReader{r}}
+}
+
+// DecodedLen 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 }
diff --git a/src/encoding/base64/base64_test.go b/src/encoding/base64/base64_test.go
new file mode 100644
index 0000000000..7d199bfa08
--- /dev/null
+++ b/src/encoding/base64/base64_test.go
@@ -0,0 +1,360 @@
+// 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"
+	"errors"
+	"io"
+	"io/ioutil"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+)
+
+type testpair struct {
+	decoded, encoded string
+}
+
+var pairs = []testpair{
+	// RFC 3548 examples
+	{"\x14\xfb\x9c\x03\xd9\x7e", "FPucA9l+"},
+	{"\x14\xfb\x9c\x03\xd9", "FPucA9k="},
+	{"\x14\xfb\x9c\x03", "FPucAw=="},
+
+	// RFC 4648 examples
+	{"", ""},
+	{"f", "Zg=="},
+	{"fo", "Zm8="},
+	{"foo", "Zm9v"},
+	{"foob", "Zm9vYg=="},
+	{"fooba", "Zm9vYmE="},
+	{"foobar", "Zm9vYmFy"},
+
+	// Wikipedia examples
+	{"sure.", "c3VyZS4="},
+	{"sure", "c3VyZQ=="},
+	{"sur", "c3Vy"},
+	{"su", "c3U="},
+	{"leasure.", "bGVhc3VyZS4="},
+	{"easure.", "ZWFzdXJlLg=="},
+	{"asure.", "YXN1cmUu"},
+	{"sure.", "c3VyZS4="},
+}
+
+var bigtest = testpair{
+	"Twas brillig, and the slithy toves",
+	"VHdhcyBicmlsbGlnLCBhbmQgdGhlIHNsaXRoeSB0b3Zlcw==",
+}
+
+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 TestEncode(t *testing.T) {
+	for _, p := range pairs {
+		got := StdEncoding.EncodeToString([]byte(p.decoded))
+		testEqual(t, "Encode(%q) = %q, want %q", p.decoded, got, p.encoded)
+	}
+}
+
+func TestEncoder(t *testing.T) {
+	for _, p := range pairs {
+		bb := &bytes.Buffer{}
+		encoder := NewEncoder(StdEncoding, bb)
+		encoder.Write([]byte(p.decoded))
+		encoder.Close()
+		testEqual(t, "Encode(%q) = %q, want %q", p.decoded, bb.String(), p.encoded)
+	}
+}
+
+func TestEncoderBuffering(t *testing.T) {
+	input := []byte(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, 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, 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(dbuf, []byte(p.encoded))
+		testEqual(t, "Decode(%q) = error %v, want %v", p.encoded, err, 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)
+
+		dbuf, err = StdEncoding.DecodeString(p.encoded)
+		testEqual(t, "DecodeString(%q) = error %v, want %v", p.encoded, err, error(nil))
+		testEqual(t, "DecodeString(%q) = %q, want %q", string(dbuf), p.decoded)
+	}
+}
+
+func TestDecoder(t *testing.T) {
+	for _, p := range pairs {
+		decoder := NewDecoder(StdEncoding, strings.NewReader(p.encoded))
+		dbuf := make([]byte, StdEncoding.DecodedLen(len(p.encoded)))
+		count, err := decoder.Read(dbuf)
+		if err != nil && err != io.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 != io.EOF {
+			count, err = decoder.Read(dbuf)
+		}
+		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(StdEncoding, 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) {
+	testCases := []struct {
+		input  string
+		offset int // -1 means no corruption.
+	}{
+		{"", -1},
+		{"!!!!", 0},
+		{"====", 0},
+		{"x===", 1},
+		{"=AAA", 0},
+		{"A=AA", 1},
+		{"AA=A", 2},
+		{"AA==A", 4},
+		{"AAA=AAAA", 4},
+		{"AAAAA", 4},
+		{"AAAAAA", 4},
+		{"A=", 1},
+		{"A==", 1},
+		{"AA=", 3},
+		{"AA==", -1},
+		{"AAA=", -1},
+		{"AAAA", -1},
+		{"AAAAAA=", 7},
+		{"YWJjZA=====", 8},
+	}
+	for _, tc := range testCases {
+		dbuf := make([]byte, StdEncoding.DecodedLen(len(tc.input)))
+		_, err := StdEncoding.Decode(dbuf, []byte(tc.input))
+		if tc.offset == -1 {
+			if err != nil {
+				t.Error("Decoder wrongly detected coruption in", tc.input)
+			}
+			continue
+		}
+		switch err := err.(type) {
+		case CorruptInputError:
+			testEqual(t, "Corruption in %q at offset %v, want %v", tc.input, int(err), tc.offset)
+		default:
+			t.Error("Decoder failed to detect corruption in", tc)
+		}
+	}
+}
+
+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 := ioutil.ReadAll(NewDecoder(StdEncoding, encoded))
+	if err != nil {
+		t.Fatalf("ioutil.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 TestNewLineCharacters(t *testing.T) {
+	// Each of these should decode to the string "sure", without errors.
+	const expected = "sure"
+	examples := []string{
+		"c3VyZQ==",
+		"c3VyZQ==\r",
+		"c3VyZQ==\n",
+		"c3VyZQ==\r\n",
+		"c3VyZ\r\nQ==",
+		"c3V\ryZ\nQ==",
+		"c3V\nyZ\rQ==",
+		"c3VyZ\nQ==",
+		"c3VyZQ\n==",
+		"c3VyZQ=\n=",
+		"c3VyZQ=\r\n\r\n=",
+	}
+	for _, e := range examples {
+		buf, err := StdEncoding.DecodeString(e)
+		if err != nil {
+			t.Errorf("Decode(%q) failed: %v", e, err)
+			continue
+		}
+		if s := string(buf); s != expected {
+			t.Errorf("Decode(%q) = %q, want %q", e, s, expected)
+		}
+	}
+}
+
+type nextRead struct {
+	n   int   // bytes to return
+	err error // error to return
+}
+
+// faultInjectReader returns data from source, rate-limited
+// and with the errors as written to nextc.
+type faultInjectReader struct {
+	source string
+	nextc  <-chan nextRead
+}
+
+func (r *faultInjectReader) Read(p []byte) (int, error) {
+	nr := <-r.nextc
+	if len(p) > nr.n {
+		p = p[:nr.n]
+	}
+	n := copy(p, r.source)
+	r.source = r.source[n:]
+	return n, nr.err
+}
+
+// tests that we don't ignore errors from our underlying reader
+func TestDecoderIssue3577(t *testing.T) {
+	next := make(chan nextRead, 10)
+	wantErr := errors.New("my error")
+	next <- nextRead{5, nil}
+	next <- nextRead{10, wantErr}
+	next <- nextRead{0, wantErr}
+	d := NewDecoder(StdEncoding, &faultInjectReader{
+		source: "VHdhcyBicmlsbGlnLCBhbmQgdGhlIHNsaXRoeSB0b3Zlcw==", // twas brillig...
+		nextc:  next,
+	})
+	errc := make(chan error)
+	go func() {
+		_, err := ioutil.ReadAll(d)
+		errc <- err
+	}()
+	select {
+	case err := <-errc:
+		if err != wantErr {
+			t.Errorf("got error %v; want %v", err, wantErr)
+		}
+	case <-time.After(5 * time.Second):
+		t.Errorf("timeout; Decoder blocked without returning an error")
+	}
+}
+
+func TestDecoderIssue4779(t *testing.T) {
+	encoded := `CP/EAT8AAAEF
+AQEBAQEBAAAAAAAAAAMAAQIEBQYHCAkKCwEAAQUBAQEBAQEAAAAAAAAAAQACAwQFBgcICQoLEAAB
+BAEDAgQCBQcGCAUDDDMBAAIRAwQhEjEFQVFhEyJxgTIGFJGhsUIjJBVSwWIzNHKC0UMHJZJT8OHx
+Y3M1FqKygyZEk1RkRcKjdDYX0lXiZfKzhMPTdePzRieUpIW0lcTU5PSltcXV5fVWZnaGlqa2xtbm
+9jdHV2d3h5ent8fX5/cRAAICAQIEBAMEBQYHBwYFNQEAAhEDITESBEFRYXEiEwUygZEUobFCI8FS
+0fAzJGLhcoKSQ1MVY3M08SUGFqKygwcmNcLSRJNUoxdkRVU2dGXi8rOEw9N14/NGlKSFtJXE1OT0
+pbXF1eX1VmZ2hpamtsbW5vYnN0dXZ3eHl6e3x//aAAwDAQACEQMRAD8A9VSSSSUpJJJJSkkkJ+Tj
+1kiy1jCJJDnAcCTykpKkuQ6p/jN6FgmxlNduXawwAzaGH+V6jn/R/wCt71zdn+N/qL3kVYFNYB4N
+ji6PDVjWpKp9TSXnvTf8bFNjg3qOEa2n6VlLpj/rT/pf567DpX1i6L1hs9Py67X8mqdtg/rUWbbf
++gkp0kkkklKSSSSUpJJJJT//0PVUkkklKVLq3WMDpGI7KzrNjADtYNXvI/Mqr/Pd/q9W3vaxjnvM
+NaCXE9gNSvGPrf8AWS3qmba5jjsJhoB0DAf0NDf6sevf+/lf8Hj0JJATfWT6/dV6oXU1uOLQeKKn
+EQP+Hubtfe/+R7Mf/g7f5xcocp++Z11JMCJPgFBxOg7/AOuqDx8I/ikpkXkmSdU8mJIJA/O8EMAy
+j+mSARB/17pKVXYWHXjsj7yIex0PadzXMO1zT5KHoNA3HT8ietoGhgjsfA+CSnvvqh/jJtqsrwOv
+2b6NGNzXfTYexzJ+nU7/ALkf4P8Awv6P9KvTQQ4AgyDqCF85Pho3CTB7eHwXoH+LT65uZbX9X+o2
+bqbPb06551Y4
+`
+	encodedShort := strings.Replace(encoded, "\n", "", -1)
+
+	dec := NewDecoder(StdEncoding, strings.NewReader(encoded))
+	res1, err := ioutil.ReadAll(dec)
+	if err != nil {
+		t.Errorf("ReadAll failed: %v", err)
+	}
+
+	dec = NewDecoder(StdEncoding, strings.NewReader(encodedShort))
+	var res2 []byte
+	res2, err = ioutil.ReadAll(dec)
+	if err != nil {
+		t.Errorf("ReadAll failed: %v", err)
+	}
+
+	if !bytes.Equal(res1, res2) {
+		t.Error("Decoded results not equal")
+	}
+}
+
+func TestDecoderIssue7733(t *testing.T) {
+	s, err := StdEncoding.DecodeString("YWJjZA=====")
+	want := CorruptInputError(8)
+	if !reflect.DeepEqual(want, err) {
+		t.Errorf("Error = %v; want CorruptInputError(8)", err)
+	}
+	if string(s) != "abcd" {
+		t.Errorf("DecodeString = %q; want abcd", s)
+	}
+}
+
+func BenchmarkEncodeToString(b *testing.B) {
+	data := make([]byte, 8192)
+	b.SetBytes(int64(len(data)))
+	for i := 0; i < b.N; i++ {
+		StdEncoding.EncodeToString(data)
+	}
+}
+
+func BenchmarkDecodeString(b *testing.B) {
+	data := StdEncoding.EncodeToString(make([]byte, 8192))
+	b.SetBytes(int64(len(data)))
+	for i := 0; i < b.N; i++ {
+		StdEncoding.DecodeString(data)
+	}
+}
diff --git a/src/encoding/base64/example_test.go b/src/encoding/base64/example_test.go
new file mode 100644
index 0000000000..d18b856a0f
--- /dev/null
+++ b/src/encoding/base64/example_test.go
@@ -0,0 +1,45 @@
+// Copyright 2012 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.
+
+// Keep in sync with ../base32/example_test.go.
+
+package base64_test
+
+import (
+	"encoding/base64"
+	"fmt"
+	"os"
+)
+
+func ExampleEncoding_EncodeToString() {
+	data := []byte("any + old & data")
+	str := base64.StdEncoding.EncodeToString(data)
+	fmt.Println(str)
+	// Output:
+	// YW55ICsgb2xkICYgZGF0YQ==
+}
+
+func ExampleEncoding_DecodeString() {
+	str := "c29tZSBkYXRhIHdpdGggACBhbmQg77u/"
+	data, err := base64.StdEncoding.DecodeString(str)
+	if err != nil {
+		fmt.Println("error:", err)
+		return
+	}
+	fmt.Printf("%q\n", data)
+	// Output:
+	// "some data with \x00 and \ufeff"
+}
+
+func ExampleNewEncoder() {
+	input := []byte("foo\x00bar")
+	encoder := base64.NewEncoder(base64.StdEncoding, os.Stdout)
+	encoder.Write(input)
+	// Must close the encoder when finished to flush any partial blocks.
+	// If you comment out the following line, the last partial block "r"
+	// won't be encoded.
+	encoder.Close()
+	// Output:
+	// Zm9vAGJhcg==
+}