/*
* Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.nio.cs;
import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CharsetEncoder;
import java.nio.charset.CoderResult;
/* Legal UTF-8 Byte Sequences
*
* # Code Points Bits Bit/Byte pattern
* 1 7 0xxxxxxx
* U+0000..U+007F 00..7F
*
* 2 11 110xxxxx 10xxxxxx
* U+0080..U+07FF C2..DF 80..BF
*
* 3 16 1110xxxx 10xxxxxx 10xxxxxx
* U+0800..U+0FFF E0 A0..BF 80..BF
* U+1000..U+FFFF E1..EF 80..BF 80..BF
*
* 4 21 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
* U+10000..U+3FFFF F0 90..BF 80..BF 80..BF
* U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF
* U+100000..U10FFFF F4 80..8F 80..BF 80..BF
*
*/
class UTF_8 extends Unicode
{
public UTF_8() {
super("UTF-8", StandardCharsets.aliases_UTF_8);
}
public String historicalName() {
return "UTF8";
}
public CharsetDecoder newDecoder() {
return new Decoder(this);
}
public CharsetEncoder newEncoder() {
return new Encoder(this);
}
static final void updatePositions(Buffer src, int sp,
Buffer dst, int dp) {
src.position(sp - src.arrayOffset());
dst.position(dp - dst.arrayOffset());
}
private static class Decoder extends CharsetDecoder {
private Decoder(Charset cs) {
super(cs, 1.0f, 1.0f);
}
private static boolean isNotContinuation(int b) {
return (b & 0xc0) != 0x80;
}
// [C2..DF] [80..BF]
private static boolean isMalformed2(int b1, int b2) {
return (b1 & 0x1e) == 0x0 || (b2 & 0xc0) != 0x80;
}
// [E0] [A0..BF] [80..BF]
// [E1..EF] [80..BF] [80..BF]
private static boolean isMalformed3(int b1, int b2, int b3) {
return (b1 == (byte)0xe0 && (b2 & 0xe0) == 0x80) ||
(b2 & 0xc0) != 0x80 || (b3 & 0xc0) != 0x80;
}
// [F0] [90..BF] [80..BF] [80..BF]
// [F1..F3] [80..BF] [80..BF] [80..BF]
// [F4] [80..8F] [80..BF] [80..BF]
// only check 80-be range here, the [0xf0,0x80...] and [0xf4,0x90-...]
// will be checked by Surrogate.neededFor(uc)
private static boolean isMalformed4(int b2, int b3, int b4) {
return (b2 & 0xc0) != 0x80 || (b3 & 0xc0) != 0x80 ||
(b4 & 0xc0) != 0x80;
}
private static CoderResult lookupN(ByteBuffer src, int n)
{
for (int i = 1; i < n; i++) {
if (isNotContinuation(src.get()))
return CoderResult.malformedForLength(i);
}
return CoderResult.malformedForLength(n);
}
private static CoderResult malformedN(ByteBuffer src, int nb) {
switch (nb) {
case 1:
int b1 = src.get();
if ((b1 >> 2) == -2) {
// 5 bytes 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
if (src.remaining() < 4)
return CoderResult.UNDERFLOW;
return lookupN(src, 5);
}
if ((b1 >> 1) == -2) {
// 6 bytes 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
if (src.remaining() < 5)
return CoderResult.UNDERFLOW;
return lookupN(src, 6);
}
return CoderResult.malformedForLength(1);
case 2: // always 1
return CoderResult.malformedForLength(1);
case 3:
b1 = src.get();
int b2 = src.get(); // no need to lookup b3
return CoderResult.malformedForLength(
((b1 == (byte)0xe0 && (b2 & 0xe0) == 0x80) ||
isNotContinuation(b2))?1:2);
case 4: // we don't care the speed here
b1 = src.get() & 0xff;
b2 = src.get() & 0xff;
if (b1 > 0xf4 ||
(b1 == 0xf0 && (b2 < 0x90 || b2 > 0xbf)) ||
(b1 == 0xf4 && (b2 & 0xf0) != 0x80) ||
isNotContinuation(b2))
return CoderResult.malformedForLength(1);
if (isNotContinuation(src.get()))
return CoderResult.malformedForLength(2);
return CoderResult.malformedForLength(3);
default:
assert false;
return null;
}
}
private static CoderResult malformed(ByteBuffer src, int sp,
CharBuffer dst, int dp,
int nb)
{
src.position(sp - src.arrayOffset());
CoderResult cr = malformedN(src, nb);
updatePositions(src, sp, dst, dp);
return cr;
}
private static CoderResult malformed(ByteBuffer src,
int mark, int nb)
{
src.position(mark);
CoderResult cr = malformedN(src, nb);
src.position(mark);
return cr;
}
private static CoderResult xflow(Buffer src, int sp, int sl,
Buffer dst, int dp, int nb) {
updatePositions(src, sp, dst, dp);
return (nb == 0 || sl - sp < nb)
?CoderResult.UNDERFLOW:CoderResult.OVERFLOW;
}
private static CoderResult xflow(Buffer src, int mark, int nb) {
CoderResult cr = (nb == 0 || src.remaining() < (nb - 1))
?CoderResult.UNDERFLOW:CoderResult.OVERFLOW;
src.position(mark);
return cr;
}
private CoderResult decodeArrayLoop(ByteBuffer src,
CharBuffer dst)
{
// This method is optimized for ASCII input.
byte[] sa = src.array();
int sp = src.arrayOffset() + src.position();
int sl = src.arrayOffset() + src.limit();
char[] da = dst.array();
int dp = dst.arrayOffset() + dst.position();
int dl = dst.arrayOffset() + dst.limit();
int dlASCII = dp + Math.min(sl - sp, dl - dp);
// ASCII only loop
while (dp < dlASCII && sa[sp] >= 0)
da[dp++] = (char)sa[sp++];
while (sp < sl) {
int b1 = sa[sp];
if (b1 >= 0) {
// 1 byte, 7 bits: 0xxxxxxx
if (dp >= dl)
return xflow(src, sp, sl, dst, dp, 1);
da[dp++] = (char)b1;
sp++;
} else if ((b1 >> 5) == -2) {
// 2 bytes, 11 bits: 110xxxxx 10xxxxxx
if (sl - sp < 2 || dp >= dl)
return xflow(src, sp, sl, dst, dp, 2);
int b2 = sa[sp + 1];
if (isMalformed2(b1, b2))
return malformed(src, sp, dst, dp, 2);
da[dp++] = (char) (((b1 << 6) ^ b2) ^ 0x0f80);
sp += 2;
} else if ((b1 >> 4) == -2) {
// 3 bytes, 16 bits: 1110xxxx 10xxxxxx 10xxxxxx
if (sl - sp < 3 || dp >= dl)
return xflow(src, sp, sl, dst, dp, 3);
int b2 = sa[sp + 1];
int b3 = sa[sp + 2];
if (isMalformed3(b1, b2, b3))
return malformed(src, sp, dst, dp, 3);
da[dp++] = (char) (((b1 << 12) ^ (b2 << 6) ^ b3) ^ 0x1f80);
sp += 3;
} else if ((b1 >> 3) == -2) {
// 4 bytes, 21 bits: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
if (sl - sp < 4 || dl - dp < 2)
return xflow(src, sp, sl, dst, dp, 4);
int b2 = sa[sp + 1];
int b3 = sa[sp + 2];
int b4 = sa[sp + 3];
int uc = ((b1 & 0x07) << 18) |
((b2 & 0x3f) << 12) |
((b3 & 0x3f) << 06) |
(b4 & 0x3f);
if (isMalformed4(b2, b3, b4) ||
!Surrogate.neededFor(uc)) {
return malformed(src, sp, dst, dp, 4);
}
da[dp++] = Surrogate.high(uc);
da[dp++] = Surrogate.low(uc);
sp += 4;
} else
return malformed(src, sp, dst, dp, 1);
}
return xflow(src, sp, sl, dst, dp, 0);
}
private CoderResult decodeBufferLoop(ByteBuffer src,
CharBuffer dst)
{
int mark = src.position();
int limit = src.limit();
while (mark < limit) {
int b1 = src.get();
if (b1 >= 0) {
// 1 byte, 7 bits: 0xxxxxxx
if (dst.remaining() < 1)
return xflow(src, mark, 1); //overflow
dst.put((char)b1);
mark++;
} else if ((b1 >> 5) == -2) {
// 2 bytes, 11 bits: 110xxxxx 10xxxxxx
if (limit - mark < 2|| dst.remaining() < 1)
return xflow(src, mark, 2);
int b2 = src.get();
if (isMalformed2(b1, b2))
return malformed(src, mark, 2);
dst.put((char) (((b1 << 6) ^ b2) ^ 0x0f80));
mark += 2;
} else if ((b1 >> 4) == -2) {
// 3 bytes, 16 bits: 1110xxxx 10xxxxxx 10xxxxxx
if (limit - mark < 3 || dst.remaining() < 1)
return xflow(src, mark, 3);
int b2 = src.get();
int b3 = src.get();
if (isMalformed3(b1, b2, b3))
return malformed(src, mark, 3);
dst.put((char) (((b1 << 12) ^ (b2 << 6) ^ b3) ^ 0x1f80));
mark += 3;
} else if ((b1 >> 3) == -2) {
// 4 bytes, 21 bits: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
if (limit - mark < 4 || dst.remaining() < 2)
return xflow(src, mark, 4);
int b2 = src.get();
int b3 = src.get();
int b4 = src.get();
int uc = ((b1 & 0x07) << 18) |
((b2 & 0x3f) << 12) |
((b3 & 0x3f) << 06) |
(b4 & 0x3f);
if (isMalformed4(b2, b3, b4) ||
!Surrogate.neededFor(uc)) { // shortest form check
return malformed(src, mark, 4);
}
dst.put(Surrogate.high(uc));
dst.put(Surrogate.low(uc));
mark += 4;
} else {
return malformed(src, mark, 1);
}
}
return xflow(src, mark, 0);
}
protected CoderResult decodeLoop(ByteBuffer src,
CharBuffer dst)
{
if (src.hasArray() && dst.hasArray())
return decodeArrayLoop(src, dst);
else
return decodeBufferLoop(src, dst);
}
}
private static class Encoder extends CharsetEncoder {
private Encoder(Charset cs) {
super(cs, 1.1f, 4.0f);
}
public boolean canEncode(char c) {
return !Surrogate.is(c);
}
public boolean isLegalReplacement(byte[] repl) {
return ((repl.length == 1 && repl[0] >= 0) ||
super.isLegalReplacement(repl));
}
private static CoderResult overflow(CharBuffer src, int sp,
ByteBuffer dst, int dp) {
updatePositions(src, sp, dst, dp);
return CoderResult.OVERFLOW;
}
private static CoderResult overflow(CharBuffer src, int mark) {
src.position(mark);
return CoderResult.OVERFLOW;
}
private Surrogate.Parser sgp;
private CoderResult encodeArrayLoop(CharBuffer src,
ByteBuffer dst)
{
char[] sa = src.array();
int sp = src.arrayOffset() + src.position();
int sl = src.arrayOffset() + src.limit();
byte[] da = dst.array();
int dp = dst.arrayOffset() + dst.position();
int dl = dst.arrayOffset() + dst.limit();
int dlASCII = dp + Math.min(sl - sp, dl - dp);
//ASCII only loop
while (dp < dlASCII && sa[sp] < '\u0080')
da[dp++] = (byte) sa[sp++];
while (sp < sl) {
int c = sa[sp];
if (c < 0x80) {
// Have at most seven bits
if (dp >= dl)
return overflow(src, sp, dst, dp);
da[dp++] = (byte)c;
} else if (c < 0x800) {
// 2 bytes, 11 bits
if (dl - dp < 2)
return overflow(src, sp, dst, dp);
da[dp++] = (byte)(0xc0 | ((c >> 06)));
da[dp++] = (byte)(0x80 | (c & 0x3f));
} else if (Surrogate.is(c)) {
// Have a surrogate pair
if (sgp == null)
sgp = new Surrogate.Parser();
int uc = sgp.parse((char)c, sa, sp, sl);
if (uc < 0) {
updatePositions(src, sp, dst, dp);
return sgp.error();
}
if (dl - dp < 4)
return overflow(src, sp, dst, dp);
da[dp++] = (byte)(0xf0 | ((uc >> 18)));
da[dp++] = (byte)(0x80 | ((uc >> 12) & 0x3f));
da[dp++] = (byte)(0x80 | ((uc >> 06) & 0x3f));
da[dp++] = (byte)(0x80 | (uc & 0x3f));
sp++; // 2 chars
} else {
// 3 bytes, 16 bits
if (dl - dp < 3)
return overflow(src, sp, dst, dp);
da[dp++] = (byte)(0xe0 | ((c >> 12)));
da[dp++] = (byte)(0x80 | ((c >> 06) & 0x3f));
da[dp++] = (byte)(0x80 | (c & 0x3f));
}
sp++;
}
updatePositions(src, sp, dst, dp);
return CoderResult.UNDERFLOW;
}
private CoderResult encodeBufferLoop(CharBuffer src,
ByteBuffer dst)
{
int mark = src.position();
while (src.hasRemaining()) {
int c = src.get();
if (c < 0x80) {
// Have at most seven bits
if (!dst.hasRemaining())
return overflow(src, mark);
dst.put((byte)c);
} else if (c < 0x800) {
// 2 bytes, 11 bits
if (dst.remaining() < 2)
return overflow(src, mark);
dst.put((byte)(0xc0 | ((c >> 06))));
dst.put((byte)(0x80 | (c & 0x3f)));
} else if (Surrogate.is(c)) {
// Have a surrogate pair
if (sgp == null)
sgp = new Surrogate.Parser();
int uc = sgp.parse((char)c, src);
if (uc < 0) {
src.position(mark);
return sgp.error();
}
if (dst.remaining() < 4)
return overflow(src, mark);
dst.put((byte)(0xf0 | ((uc >> 18))));
dst.put((byte)(0x80 | ((uc >> 12) & 0x3f)));
dst.put((byte)(0x80 | ((uc >> 06) & 0x3f)));
dst.put((byte)(0x80 | (uc & 0x3f)));
mark++; //2 chars
} else {
// 3 bytes, 16 bits
if (dst.remaining() < 3)
return overflow(src, mark);
dst.put((byte)(0xe0 | ((c >> 12))));
dst.put((byte)(0x80 | ((c >> 06) & 0x3f)));
dst.put((byte)(0x80 | (c & 0x3f)));
}
mark++;
}
src.position(mark);
return CoderResult.UNDERFLOW;
}
protected final CoderResult encodeLoop(CharBuffer src,
ByteBuffer dst)
{
if (src.hasArray() && dst.hasArray())
return encodeArrayLoop(src, dst);
else
return encodeBufferLoop(src, dst);
}
}
}