186 lines
7.2 KiB
Java
186 lines
7.2 KiB
Java
/*
|
|
* Copyright (c) 2015 Mozilla Foundation
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a
|
|
* copy of this software and associated documentation files (the "Software"),
|
|
* to deal in the Software without restriction, including without limitation
|
|
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
|
|
* and/or sell copies of the Software, and to permit persons to whom the
|
|
* Software is furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
|
|
* DEALINGS IN THE SOFTWARE.
|
|
*/
|
|
|
|
package nu.validator.encoding;
|
|
|
|
import java.nio.ByteBuffer;
|
|
import java.nio.CharBuffer;
|
|
import java.nio.charset.Charset;
|
|
import java.nio.charset.CoderResult;
|
|
|
|
public class Big5Encoder extends Encoder {
|
|
|
|
private char utf16Lead = '\u0000';
|
|
|
|
private byte pendingTrail = 0;
|
|
|
|
protected Big5Encoder(Charset cs) {
|
|
super(cs, 1.5f, 2.0f);
|
|
}
|
|
|
|
@Override protected CoderResult encodeLoop(CharBuffer in, ByteBuffer out) {
|
|
assert !((this.reportMalformed || this.reportUnmappable) && (utf16Lead != '\u0000')):
|
|
"When reporting, this method should never return with utf16Lead set.";
|
|
if (pendingTrail != 0) {
|
|
if (!out.hasRemaining()) {
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
out.put(pendingTrail);
|
|
pendingTrail = 0;
|
|
}
|
|
for (;;) {
|
|
if (!in.hasRemaining()) {
|
|
return CoderResult.UNDERFLOW;
|
|
}
|
|
if (!out.hasRemaining()) {
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
boolean isAstral; // true means Plane 2, false means BMP
|
|
char lowBits; // The low 16 bits of the code point
|
|
char codeUnit = in.get();
|
|
int highBits = (codeUnit & 0xFC00);
|
|
if (highBits == 0xD800) {
|
|
// high surrogate
|
|
if (utf16Lead != '\u0000') {
|
|
// High surrogate follows another high surrogate. The
|
|
// *previous* code unit is in error.
|
|
if (this.reportMalformed) {
|
|
// The caller had better adhere to the API contract.
|
|
// Otherwise, this may throw.
|
|
in.position(in.position() - 2);
|
|
utf16Lead = '\u0000';
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
out.put((byte) '?');
|
|
}
|
|
utf16Lead = codeUnit;
|
|
continue;
|
|
}
|
|
if (highBits == 0xDC00) {
|
|
// low surrogate
|
|
if (utf16Lead == '\u0000') {
|
|
// Got low surrogate without a previous high surrogate
|
|
if (this.reportMalformed) {
|
|
in.position(in.position() - 1);
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
out.put((byte) '?');
|
|
continue;
|
|
}
|
|
int codePoint = (utf16Lead << 10) + codeUnit - 56613888;
|
|
utf16Lead = '\u0000';
|
|
// Plane 2 is the only astral plane that has potentially
|
|
// Big5-encodable characters.
|
|
if ((0xFF0000 & codePoint) != 0x20000) {
|
|
if (this.reportUnmappable) {
|
|
in.position(in.position() - 2);
|
|
return CoderResult.unmappableForLength(2);
|
|
}
|
|
out.put((byte) '?');
|
|
continue;
|
|
}
|
|
isAstral = true;
|
|
lowBits = (char)(codePoint & 0xFFFF);
|
|
} else {
|
|
// not a surrogate
|
|
if (utf16Lead != '\u0000') {
|
|
// Non-surrogate follows a high surrogate. The *previous*
|
|
// code unit is in error.
|
|
utf16Lead = '\u0000';
|
|
if (this.reportMalformed) {
|
|
// The caller had better adhere to the API contract.
|
|
// Otherwise, this may throw.
|
|
in.position(in.position() - 2);
|
|
return CoderResult.malformedForLength(1);
|
|
}
|
|
out.put((byte) '?');
|
|
// Let's unconsume this code unit and reloop in order to
|
|
// re-check if the output buffer still has space.
|
|
in.position(in.position() - 1);
|
|
continue;
|
|
}
|
|
isAstral = false;
|
|
lowBits = codeUnit;
|
|
}
|
|
// isAstral now tells us if we have a Plane 2 or a BMP character.
|
|
// lowBits tells us the low 16 bits.
|
|
// After all the above setup to deal with UTF-16, we are now
|
|
// finally ready to follow the spec.
|
|
if (!isAstral && lowBits <= 0x7F) {
|
|
out.put((byte)lowBits);
|
|
continue;
|
|
}
|
|
int pointer = Big5Data.findPointer(lowBits, isAstral);
|
|
if (pointer == 0) {
|
|
if (this.reportUnmappable) {
|
|
if (isAstral) {
|
|
in.position(in.position() - 2);
|
|
return CoderResult.unmappableForLength(2);
|
|
}
|
|
in.position(in.position() - 1);
|
|
return CoderResult.unmappableForLength(1);
|
|
}
|
|
out.put((byte)'?');
|
|
continue;
|
|
}
|
|
int lead = pointer / 157 + 0x81;
|
|
int trail = pointer % 157;
|
|
if (trail < 0x3F) {
|
|
trail += 0x40;
|
|
} else {
|
|
trail += 0x62;
|
|
}
|
|
out.put((byte)lead);
|
|
if (!out.hasRemaining()) {
|
|
pendingTrail = (byte)trail;
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
out.put((byte)trail);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
@Override protected CoderResult implFlush(ByteBuffer out) {
|
|
if (pendingTrail != 0) {
|
|
if (!out.hasRemaining()) {
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
out.put(pendingTrail);
|
|
pendingTrail = 0;
|
|
}
|
|
if (utf16Lead != '\u0000') {
|
|
assert !this.reportMalformed: "How come utf16Lead got to be non-zero when decodeLoop() returned in the reporting mode?";
|
|
if (!out.hasRemaining()) {
|
|
return CoderResult.OVERFLOW;
|
|
}
|
|
out.put((byte)'?');
|
|
utf16Lead = '\u0000';
|
|
}
|
|
return CoderResult.UNDERFLOW;
|
|
}
|
|
|
|
@Override protected void implReset() {
|
|
utf16Lead = '\u0000';
|
|
pendingTrail = 0;
|
|
}
|
|
}
|