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1 package org.python.parser;
2
3
8
9 public final class ReaderCharStream implements CharStream
10 {
11 public static final boolean staticFlag = false;
12 int bufsize;
13 int available;
14 int tokenBegin;
15 public int bufpos = -1;
16 private int bufline[];
17 private int bufcolumn[];
18
19 private int column = 0;
20 private int line = 1;
21
22 private boolean prevCharIsCR = false;
23 private boolean prevCharIsLF = false;
24
25 private java.io.Reader  inputStream;
26
27 private char[] buffer;
28 private int maxNextCharInd = 0;
29 private int inBuf = 0;
30
31 private final void ExpandBuff(boolean wrapAround)
32 {
33 char[] newbuffer = new char[bufsize + 2048];
34 int newbufline[] = new int[bufsize + 2048];
35 int newbufcolumn[] = new int[bufsize + 2048];
36
37 try
38 {
39 if (wrapAround)
40 {
41 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
42 System.arraycopy(buffer, 0, newbuffer,
43 bufsize - tokenBegin, bufpos);
44 buffer = newbuffer;
45
46 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
47 System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos);
48 bufline = newbufline;
49
50 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
51 System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos);
52 bufcolumn = newbufcolumn;
53
54 maxNextCharInd = (bufpos += (bufsize - tokenBegin));
55 }
56 else
57 {
58 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
59 buffer = newbuffer;
60
61 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
62 bufline = newbufline;
63
64 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
65 bufcolumn = newbufcolumn;
66
67 maxNextCharInd = (bufpos -= tokenBegin);
68 }
69 }
70 catch (Throwable t)
71 {
72 throw new Error (t.getMessage());
73 }
74
75
76 bufsize += 2048;
77 available = bufsize;
78 tokenBegin = 0;
79 }
80
81 private final void FillBuff() throws java.io.IOException
82 {
83 if (maxNextCharInd == available)
84 {
85 if (available == bufsize)
86 {
87 if (tokenBegin > 2048)
88 {
89 bufpos = maxNextCharInd = 0;
90 available = tokenBegin;
91 }
92 else if (tokenBegin < 0)
93 bufpos = maxNextCharInd = 0;
94 else
95 ExpandBuff(false);
96 }
97 else if (available > tokenBegin)
98 available = bufsize;
99 else if ((tokenBegin - available) < 2048)
100 ExpandBuff(true);
101 else
102 available = tokenBegin;
103 }
104
105 int i;
106 try {
107 if ((i = inputStream.read(buffer, maxNextCharInd,
108 available - maxNextCharInd)) == -1)
109 {
110 inputStream.close();
111 throw new java.io.IOException ();
112 }
113 else
114 maxNextCharInd += i;
115 return;
116 }
117 catch(java.io.IOException e) {
118 --bufpos;
119 backup(0);
120 if (tokenBegin == -1)
121 tokenBegin = bufpos;
122 throw e;
123 }
124 }
125
126 public final char BeginToken() throws java.io.IOException
127 {
128 tokenBegin = -1;
129 char c = readChar();
130 tokenBegin = bufpos;
131
132 return c;
133 }
134
135 private final void UpdateLineColumn(char c)
136 {
137 column++;
138
139 if (prevCharIsLF)
140 {
141 prevCharIsLF = false;
142 line += (column = 1);
143 }
144 else if (prevCharIsCR)
145 {
146 prevCharIsCR = false;
147 if (c == '\n')
148 {
149 prevCharIsLF = true;
150 }
151 else
152 line += (column = 1);
153 }
154
155 switch (c)
156 {
157 case '\r' :
158 prevCharIsCR = true;
159 break;
160 case '\n' :
161 prevCharIsLF = true;
162 break;
163 case '\t' :
164 column--;
165 column += (8 - (column & 07));
166 break;
167 default :
168 break;
169 }
170
171 bufline[bufpos] = line;
172 bufcolumn[bufpos] = column;
173 }
174
175 public final char readChar() throws java.io.IOException
176 {
177 if (inBuf > 0)
178 {
179 --inBuf;
180 return buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos];
181 }
182
183 if (++bufpos >= maxNextCharInd)
184 FillBuff();
185
186 char c = buffer[bufpos];
187
188 UpdateLineColumn(c);
189 return (c);
190 }
191
192
196
197 public final int getColumn() {
198 return bufcolumn[bufpos];
199 }
200
201
205
206 public final int getLine() {
207 return bufline[bufpos];
208 }
209
210 public final int getEndColumn() {
211 return bufcolumn[bufpos];
212 }
213
214 public final int getEndLine() {
215 return bufline[bufpos];
216 }
217
218 public final int getBeginColumn() {
219 return bufcolumn[tokenBegin];
220 }
221
222 public final int getBeginLine() {
223 return bufline[tokenBegin];
224 }
225
226 public final void backup(int amount) {
227
228 inBuf += amount;
229 if ((bufpos -= amount) < 0)
230 bufpos += bufsize;
231 }
232
233 public ReaderCharStream(java.io.Reader dstream)
234 {
235 inputStream = dstream;
236 line = 1;
237 column = 0;
238
239 available = bufsize = 4096;
240 buffer = new char[bufsize];
241 bufline = new int[bufsize];
242 bufcolumn = new int[bufsize];
243 }
244
245 public final String GetImage()
246 {
247 if (bufpos >= tokenBegin)
248 return new String (buffer, tokenBegin, bufpos - tokenBegin + 1);
249 else
250 return new String (buffer, tokenBegin, bufsize - tokenBegin) +
251 new String (buffer, 0, bufpos + 1);
252 }
253
254 public final char[] GetSuffix(int len)
255 {
256 char[] ret = new char[len];
257
258 if ((bufpos + 1) >= len)
259 System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
260 else
261 {
262 System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
263 len - bufpos - 1);
264 System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
265 }
266
267 return ret;
268 }
269
270 public void Done()
271 {
272 buffer = null;
273 bufline = null;
274 bufcolumn = null;
275 }
276
277
280 public void adjustBeginLineColumn(int newLine, int newCol)
281 {
282 int start = tokenBegin;
283 int len;
284
285 if (bufpos >= tokenBegin)
286 {
287 len = bufpos - tokenBegin + inBuf + 1;
288 }
289 else
290 {
291 len = bufsize - tokenBegin + bufpos + 1 + inBuf;
292 }
293
294 int i = 0, j = 0, k = 0;
295 int nextColDiff = 0, columnDiff = 0;
296
297 while (i < len &&
298 bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
299 {
300 bufline[j] = newLine;
301 nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
302 bufcolumn[j] = newCol + columnDiff;
303 columnDiff = nextColDiff;
304 i++;
305 }
306
307 if (i < len)
308 {
309 bufline[j] = newLine++;
310 bufcolumn[j] = newCol + columnDiff;
311
312 while (i++ < len)
313 {
314 if (bufline[j = start % bufsize] != bufline[++start % bufsize])
315 bufline[j] = newLine++;
316 else
317 bufline[j] = newLine;
318 }
319 }
320
321 line = bufline[j];
322 column = bufcolumn[j];
323 }
324
325 }
326 |
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