1 /*
2 * Copyright 2003-2006 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 /*
27 */
28
29 package sun.nio.cs.ext;
30
31 import java.nio.ByteBuffer;
32 import java.nio.CharBuffer;
33 import java.nio.charset.Charset;
34 import java.nio.charset.CharsetDecoder;
35 import java.nio.charset.CharsetEncoder;
36 import java.nio.charset.CoderResult;
37 import java.nio.charset.CharacterCodingException;
38 import sun.nio.cs.HistoricallyNamedCharset;
39 import sun.nio.cs.US_ASCII;
40
41 public class ISO2022_CN
42 extends Charset
43 implements HistoricallyNamedCharset
44 {
45 private static final byte ISO_ESC = 0x1b;
46 private static final byte ISO_SI = 0x0f;
47 private static final byte ISO_SO = 0x0e;
48 private static final byte ISO_SS2_7 = 0x4e;
49 private static final byte ISO_SS3_7 = 0x4f;
50 private static final byte MSB = (byte)0x80;
51 private static final char REPLACE_CHAR = '\uFFFD';
52
53 private static final byte SODesigGB = 0;
54 private static final byte SODesigCNS = 1;
55
56 public ISO2022_CN() {
57 super("ISO-2022-CN", ExtendedCharsets.aliasesFor("ISO-2022-CN"));
58 }
59
60 public String historicalName() {
61 return "ISO2022CN";
62 }
63
64 public boolean contains(Charset cs) {
65 return ((cs instanceof EUC_CN) // GB2312-80 repertoire
66 || (cs instanceof US_ASCII)
67 || (cs instanceof EUC_TW) // CNS11643 repertoire
68 || (cs instanceof ISO2022_CN));
69 }
70
71 public CharsetDecoder newDecoder() {
72 return new Decoder(this);
73 }
74
75 public CharsetEncoder newEncoder() {
76 throw new UnsupportedOperationException();
77 }
78
79 public boolean canEncode() {
80 return false;
81 }
82
83 static class Decoder extends CharsetDecoder {
84 private boolean shiftOut;
85 private byte currentSODesig;
86
87 private static final Charset gb2312 = new EUC_CN();
88 private static final Charset cns = new EUC_TW();
89 private final EUC_CN.Decoder gb2312Decoder;
90 private final EUC_TW.Decoder cnsDecoder;
91
92 Decoder(Charset cs) {
93 super(cs, 1.0f, 1.0f);
94 shiftOut = false;
95 currentSODesig = SODesigGB;
96 gb2312Decoder = (EUC_CN.Decoder)gb2312.newDecoder();
97 cnsDecoder = (EUC_TW.Decoder)cns.newDecoder();
98 }
99
100 protected void implReset() {
101 shiftOut= false;
102 currentSODesig = SODesigGB;
103 }
104
105 private char cnsDecode(byte byte1, byte byte2, byte SS) {
106 byte1 |= MSB;
107 byte2 |= MSB;
108 int p = 0;
109 if (SS == ISO_SS2_7)
110 p = 1; //plane 2, index -- 1
111 else if (SS == ISO_SS3_7)
112 p = 2; //plane 3, index -- 2
113 else
114 return REPLACE_CHAR; //never happen.
115 char[] ret = cnsDecoder.toUnicode(byte1 & 0xff,
116 byte2 & 0xff,
117 p);
118 if (ret == null || ret.length == 2)
119 return REPLACE_CHAR;
120 return ret[0];
121 }
122
123 private char SODecode(byte byte1, byte byte2, byte SOD) {
124 byte1 |= MSB;
125 byte2 |= MSB;
126 if (SOD == SODesigGB) {
127 return gb2312Decoder.decodeDouble(byte1 & 0xff,
128 byte2 & 0xff);
129 } else { // SOD == SODesigCNS
130 char[] ret = cnsDecoder.toUnicode(byte1 & 0xff,
131 byte2 & 0xff,
132 0);
133 if (ret == null)
134 return REPLACE_CHAR;
135 return ret[0];
136 }
137 }
138
139 private CoderResult decodeBufferLoop(ByteBuffer src,
140 CharBuffer dst)
141 {
142 int mark = src.position();
143 byte b1 = 0, b2 = 0, b3 = 0, b4 = 0;
144 int inputSize = 0;
145 char c = REPLACE_CHAR;
146 try {
147 while (src.hasRemaining()) {
148 b1 = src.get();
149 inputSize = 1;
150
151 while (b1 == ISO_ESC ||
152 b1 == ISO_SO ||
153 b1 == ISO_SI) {
154 if (b1 == ISO_ESC) { // ESC
155 currentSODesig = SODesigGB;
156
157 if (src.remaining() < 1)
158 return CoderResult.UNDERFLOW;
159
160 b2 = src.get();
161 inputSize++;
162
163 if ((b2 & (byte)0x80) != 0)
164 return CoderResult.malformedForLength(inputSize);
165
166 if (b2 == (byte)0x24) {
167 if (src.remaining() < 1)
168 return CoderResult.UNDERFLOW;
169
170 b3 = src.get();
171 inputSize++;
172
173 if ((b3 & (byte)0x80) != 0)
174 return CoderResult.malformedForLength(inputSize);
175 if (b3 == 'A'){ // "$A"
176 currentSODesig = SODesigGB;
177 } else if (b3 == ')') {
178 if (src.remaining() < 1)
179 return CoderResult.UNDERFLOW;
180 b4 = src.get();
181 inputSize++;
182 if (b4 == 'A'){ // "$)A"
183 currentSODesig = SODesigGB;
184 } else if (b4 == 'G'){ // "$)G"
185 currentSODesig = SODesigCNS;
186 } else {
187 return CoderResult.malformedForLength(inputSize);
188 }
189 } else if (b3 == '*') {
190 if (src.remaining() < 1)
191 return CoderResult.UNDERFLOW;
192 b4 = src.get();
193 inputSize++;
194 if (b4 != 'H') { // "$*H"
195 //SS2Desig -> CNS-P1
196 return CoderResult.malformedForLength(inputSize);
197 }
198 } else if (b3 == '+') {
199 if (src.remaining() < 1)
200 return CoderResult.UNDERFLOW;
201 b4 = src.get();
202 inputSize++;
203 if (b4 != 'I'){ // "$+I"
204 //SS3Desig -> CNS-P2.
205 return CoderResult.malformedForLength(inputSize);
206 }
207 } else {
208 return CoderResult.malformedForLength(inputSize);
209 }
210 } else if (b2 == ISO_SS2_7 || b2 == ISO_SS3_7) {
211 if (src.remaining() < 2)
212 return CoderResult.UNDERFLOW;
213 b3 = src.get();
214 b4 = src.get();
215 inputSize += 2;
216 if (dst.remaining() < 1)
217 return CoderResult.OVERFLOW;
218 //SS2->CNS-P2, SS3->CNS-P3
219 c = cnsDecode(b3, b4, b2);
220 if (c == REPLACE_CHAR)
221 return CoderResult.unmappableForLength(inputSize);
222 dst.put(c);
223 } else {
224 return CoderResult.malformedForLength(inputSize);
225 }
226 } else if (b1 == ISO_SO) {
227 shiftOut = true;
228 } else if (b1 == ISO_SI) { // shift back in
229 shiftOut = false;
230 }
231 mark += inputSize;
232 if (src.remaining() < 1)
233 return CoderResult.UNDERFLOW;
234 b1 = src.get();
235 inputSize = 1;
236 }
237
238 if (dst.remaining() < 1)
239 return CoderResult.OVERFLOW;
240
241 if (!shiftOut) {
242 dst.put((char)(b1 & 0xff)); //clear the upper byte
243 mark += inputSize;
244 } else {
245 if (src.remaining() < 1)
246 return CoderResult.UNDERFLOW;
247 b2 = src.get();
248 inputSize++;
249 c = SODecode(b1, b2, currentSODesig);
250 if (c == REPLACE_CHAR)
251 return CoderResult.unmappableForLength(inputSize);
252 dst.put(c);
253 mark += inputSize;
254 }
255 }
256 return CoderResult.UNDERFLOW;
257 } finally {
258 src.position(mark);
259 }
260 }
261
262 private CoderResult decodeArrayLoop(ByteBuffer src,
263 CharBuffer dst)
264 {
265 int inputSize = 0;
266 byte b1 = 0, b2 = 0, b3 = 0, b4 = 0;
267 char c = REPLACE_CHAR;
268
269 byte[] sa = src.array();
270 int sp = src.arrayOffset() + src.position();
271 int sl = src.arrayOffset() + src.limit();
272 assert (sp <= sl);
273 sp = (sp <= sl ? sp : sl);
274
275 char[] da = dst.array();
276 int dp = dst.arrayOffset() + dst.position();
277 int dl = dst.arrayOffset() + dst.limit();
278 assert (dp <= dl);
279 dp = (dp <= dl ? dp : dl);
280
281 try {
282 while (sp < sl) {
283 b1 = sa[sp];
284 inputSize = 1;
285
286 while (b1 == ISO_ESC || b1 == ISO_SO || b1 == ISO_SI) {
287 if (b1 == ISO_ESC) { // ESC
288 currentSODesig = SODesigGB;
289
290 if (sp + 2 > sl)
291 return CoderResult.UNDERFLOW;
292
293 b2 = sa[sp + 1];
294 inputSize++;
295
296 if ((b2 & (byte)0x80) != 0)
297 return CoderResult.malformedForLength(inputSize);
298 if (b2 == (byte)0x24) {
299 if (sp + 3 > sl)
300 return CoderResult.UNDERFLOW;
301
302 b3 = sa[sp + 2];
303 inputSize++;
304
305 if ((b3 & (byte)0x80) != 0)
306 return CoderResult.malformedForLength(inputSize);
307 if (b3 == 'A'){ // "$A"
308 /* <ESC>$A is not a legal designator sequence for
309 ISO2022_CN, it is listed as an escape sequence
310 for GB2312 in ISO2022-JP-2. Keep it here just for
311 the sake of "compatibility".
312 */
313 currentSODesig = SODesigGB;
314 } else if (b3 == ')') {
315 if (sp + 4 > sl)
316 return CoderResult.UNDERFLOW;
317 b4 = sa[sp + 3];
318 inputSize++;
319
320 if (b4 == 'A'){ // "$)A"
321 currentSODesig = SODesigGB;
322 } else if (b4 == 'G'){ // "$)G"
323 currentSODesig = SODesigCNS;
324 } else {
325 return CoderResult.malformedForLength(inputSize);
326 }
327 } else if (b3 == '*') {
328 if (sp + 4 > sl)
329 return CoderResult.UNDERFLOW;
330 b4 = sa[sp + 3];
331 inputSize++;
332 if (b4 != 'H'){ // "$*H"
333 return CoderResult.malformedForLength(inputSize);
334 }
335 } else if (b3 == '+') {
336 if (sp + 4 > sl)
337 return CoderResult.UNDERFLOW;
338 b4 = sa[sp + 3];
339 inputSize++;
340 if (b4 != 'I'){ // "$+I"
341 return CoderResult.malformedForLength(inputSize);
342 }
343 } else {
344 return CoderResult.malformedForLength(inputSize);
345 }
346 } else if (b2 == ISO_SS2_7 || b2 == ISO_SS3_7) {
347 if (sp + 4 > sl) {
348 return CoderResult.UNDERFLOW;
349 }
350 b3 = sa[sp + 2];
351 b4 = sa[sp + 3];
352 if (dl - dp < 1) {
353 return CoderResult.OVERFLOW;
354 }
355 inputSize += 2;
356 c = cnsDecode(b3, b4, b2);
357 if (c == REPLACE_CHAR)
358 return CoderResult.unmappableForLength(inputSize);
359 da[dp++] = c;
360 } else {
361 return CoderResult.malformedForLength(inputSize);
362 }
363 } else if (b1 == ISO_SO) {
364 shiftOut = true;
365 } else if (b1 == ISO_SI) { // shift back in
366 shiftOut = false;
367 }
368 sp += inputSize;
369 if (sp + 1 > sl)
370 return CoderResult.UNDERFLOW;
371 b1 = sa[sp];
372 inputSize = 1;
373 }
374
375 if (dl - dp < 1) {
376 return CoderResult.OVERFLOW;
377 }
378
379 if (!shiftOut) {
380 da[dp++] = (char)(b1 & 0xff); //clear the upper byte
381 } else {
382 if (sp + 2 > sl)
383 return CoderResult.UNDERFLOW;
384 b2 = sa[sp + 1];
385 inputSize++;
386 c = SODecode(b1, b2, currentSODesig);
387 if (c == REPLACE_CHAR)
388 return CoderResult.unmappableForLength(inputSize);
389 da[dp++] = c;
390 }
391 sp += inputSize;
392 }
393 return CoderResult.UNDERFLOW;
394 } finally {
395 src.position(sp - src.arrayOffset());
396 dst.position(dp - dst.arrayOffset());
397 }
398 }
399
400 protected CoderResult decodeLoop(ByteBuffer src,
401 CharBuffer dst)
402 {
403 if (src.hasArray() && dst.hasArray())
404 return decodeArrayLoop(src, dst);
405 else
406 return decodeBufferLoop(src, dst);
407 }
408 }
409 }