1 /*
2 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.nio.cs;
27
28 import java.nio.ByteBuffer;
29 import java.nio.CharBuffer;
30 import java.nio.charset.Charset;
31 import java.nio.charset.CharsetDecoder;
32 import java.nio.charset.CharsetEncoder;
33 import java.nio.charset.CoderResult;
34
35 public class US_ASCII
36 extends Charset
37 implements HistoricallyNamedCharset
38 {
39 public static final US_ASCII INSTANCE = new US_ASCII();
40
41 public US_ASCII() {
42 super("US-ASCII", StandardCharsets.aliases_US_ASCII());
43 }
44
45 public String historicalName() {
46 return "ASCII";
47 }
48
49 public boolean contains(Charset cs) {
50 return (cs instanceof US_ASCII);
51 }
52
53 public CharsetDecoder newDecoder() {
54 return new Decoder(this);
55 }
56
57 public CharsetEncoder newEncoder() {
58 return new Encoder(this);
59 }
60
61 private static class Decoder extends CharsetDecoder {
62
63 private Decoder(Charset cs) {
64 super(cs, 1.0f, 1.0f);
65 }
66
67 private CoderResult decodeArrayLoop(ByteBuffer src,
68 CharBuffer dst)
69 {
70 byte[] sa = src.array();
71 int sp = src.arrayOffset() + src.position();
72 int sl = src.arrayOffset() + src.limit();
73 assert (sp <= sl);
74 sp = (sp <= sl ? sp : sl);
75 char[] da = dst.array();
76 int dp = dst.arrayOffset() + dst.position();
77 int dl = dst.arrayOffset() + dst.limit();
78 assert (dp <= dl);
79 dp = (dp <= dl ? dp : dl);
80
81 try {
82
83 if((dl-dp) >= (sl-sp)) {
84
85 int n = decodeASCII(sa, sp, sl-sp, da, dp);
86 sp = sp + n;
87 dp = dp + n;
88 if (sp<sl)
89 return CoderResult.malformedForLength(1);
90 return CoderResult.UNDERFLOW;
91 }
92 else {
93 int n = decodeASCII(sa, sp, dl-dp, da, dp);
94 sp = sp + n;
95 dp = dp + n;
96 if (dp<dl)
97 return CoderResult.malformedForLength(1);
98 return CoderResult.OVERFLOW;
99 }
100 } finally {
101 src.position(sp - src.arrayOffset());
102 dst.position(dp - dst.arrayOffset());
103 }
104 }
105
106 private CoderResult decodeBufferLoop(ByteBuffer src,
107 CharBuffer dst)
108 {
109 int mark = src.position();
110 try {
111 while (src.hasRemaining()) {
112 byte b = src.get();
113 if (b >= 0) {
114 if (!dst.hasRemaining())
115 return CoderResult.OVERFLOW;
116 dst.put((char)b);
117 mark++;
118 continue;
119 }
120 return CoderResult.malformedForLength(1);
121 }
122 return CoderResult.UNDERFLOW;
123 } finally {
124 src.position(mark);
125 }
126 }
127
128 protected CoderResult decodeLoop(ByteBuffer src,
129 CharBuffer dst)
130 {
131 if (src.hasArray() && dst.hasArray())
132 return decodeArrayLoop(src, dst);
133 else
134 return decodeBufferLoop(src, dst);
135 }
136
137 public final int decodeASCII(byte[] src, int sp, int len, char[] dst, int dp) {
138 int n = 0;
139 while (n < len)
140 {
141 byte b = src[sp++];
142
143 if (b >= 0){
144
145 dst[dp++] = (char)b;
146 n++;
147 continue;
148 }
149 break;
150
151 }
152
153 return n;
154 }
155 }
156
157 private static class Encoder extends CharsetEncoder {
158
159 private Encoder(Charset cs) {
160 super(cs, 1.0f, 1.0f);
161 }
162
163 public boolean canEncode(char c) {
164 return c < 0x80;
165 }
166
167 public boolean isLegalReplacement(byte[] repl) {
168 return (repl.length == 1 && repl[0] >= 0) ||
169 super.isLegalReplacement(repl);
170 }
171
172 private final Surrogate.Parser sgp = new Surrogate.Parser();
173 private CoderResult encodeArrayLoop(CharBuffer src,
174 ByteBuffer dst)
175 {
176 char[] sa = src.array();
177 int sp = src.arrayOffset() + src.position();
178 int sl = src.arrayOffset() + src.limit();
179 assert (sp <= sl);
180 sp = (sp <= sl ? sp : sl);
181 byte[] da = dst.array();
182 int dp = dst.arrayOffset() + dst.position();
183 int dl = dst.arrayOffset() + dst.limit();
184 assert (dp <= dl);
185 dp = (dp <= dl ? dp : dl);
186
187 try {
188 if((dl-dp) >= (sl-sp)) {
189
190 int n = encodeASCII(sa,sp,sl-sp,da,dp);
191 sp = sp+n;
192 dp = dp+n;
193
194 if (sp<sl)
195 {
196 char c = sa[sp];
197 if (sgp.parse(c, sa, sp, sl) < 0) {
198 return sgp.error();
199 }
200 else return sgp.unmappableResult();
201 }
202
203 return CoderResult.UNDERFLOW;
204 }
205 else {
206 int n = encodeASCII(sa,sp,dl-dp,da,dp);
207 sp = sp+n;
208 dp = dp+n;
209 if (dp<dl)
210 {
211 char c = sa[sp];
212 if (sgp.parse(c, sa, sp, sl) < 0) {
213 return sgp.error();
214 }
215 else return sgp.unmappableResult();
216 }
217 return CoderResult.OVERFLOW;
218 }
219 } finally {
220 src.position(sp - src.arrayOffset());
221 dst.position(dp - dst.arrayOffset());
222 }
223 }
224
225 private CoderResult encodeBufferLoop(CharBuffer src,
226 ByteBuffer dst)
227 {
228 int mark = src.position();
229 try {
230 while (src.hasRemaining()) {
231 char c = src.get();
232 if (c < 0x80) {
233 if (!dst.hasRemaining())
234 return CoderResult.OVERFLOW;
235 dst.put((byte)c);
236 mark++;
237 continue;
238 }
239 if (sgp.parse(c, src) < 0)
240 return sgp.error();
241 return sgp.unmappableResult();
242 }
243 return CoderResult.UNDERFLOW;
244 } finally {
245 src.position(mark);
246 }
247 }
248
249 protected CoderResult encodeLoop(CharBuffer src,
250 ByteBuffer dst)
251 {
252 if (src.hasArray() && dst.hasArray())
253 return encodeArrayLoop(src, dst);
254 else
255 return encodeBufferLoop(src, dst);
256 }
257
258 public final int encodeASCII(char[] src, int sp, int len, byte[] dst, int dp) {
259 int n = 0;
260 while (n < len) {
261 char c = src[sp++];
262 if (c < 0x80) {
263 dst[dp++] = (byte)c;
264 n++;
265 continue;
266 }
267 break;
268 }
269 return n;
270 }
271 }
272 }