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1
28
29 package com.caucho.es;
30
31 import com.caucho.util.CharBuffer;
32
33 class Printf {
34 private final static int ALT = 0x01;
35 private final static int ZERO_FILL = 0x02;
36 private final static int POS_PLUS = 0x04;
37 private final static int POS_SPACE = 0x08;
38 private final static int LALIGN = 0x10;
39 private final static int BIG = 0x20;
40 private final static int NO_TRAIL_ZERO = 0x40;
41
42 private static char []digits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
43 'a', 'b', 'c', 'd', 'e', 'f'};
44 private static char []bigDigits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
45 'A', 'B', 'C', 'D', 'E', 'F'};
46
47 private Printf()
48 {
49 }
50
51 public static String  sprintf(Call eval, int length)
52 throws Throwable
53 {
54 if (length == 0)
55 return "";
56
57 CharBuffer buf = new CharBuffer();
58
59 printf(buf, eval.getArg(0).toStr(), eval, length);
60
61 return buf.toString();
62 }
63
64 public static CharBuffer printf(CharBuffer result, ESString format,
65 Call eval, int length)
66 throws Throwable
67 {
68 int arg = 1;
69 int len = format.length();
70
71 for (int i = 0; i < len; i++) {
72 int ch;
73 int start = i;
74
75 if ((ch = format.charAt(i)) != '%') {
76 result.append((char) ch);
77 continue;
78 }
79
80 int flags = 0;
81 loop:
82 while (++i < len) {
83 switch ((ch = format.charAt(i))) {
84 case '0': flags |= ZERO_FILL; break;
85 case '+': flags |= POS_PLUS; break;
86 case ' ': flags |= POS_SPACE; break;
87 case '#': flags |= ALT; break;
88 case '-': flags |= LALIGN; break;
89
90 default: break loop;
91 }
92 }
93
94 int width = 0;
95 for (; i < len && (ch = format.charAt(i)) >= '0' && ch <= '9'; i++) {
96 width = 10 * width + ch - '0';
97 }
98
99 if (i >= len) {
100 fixBits(result, format, start, i);
101 break;
102 }
103
104 int prec = 0;
105 if (ch == '.') {
106 while (++i < len && (ch = format.charAt(i)) >= '0' && ch <= '9') {
107 prec = 10 * prec + ch - '0';
108 }
109 } else
110 prec = -1;
111
112 if (i >= len) {
113 fixBits(result, format, start, i);
114 break;
115 }
116
117 switch (ch) {
118 case '%':
119 result.append((char) '%');
120 break;
121
122 case 'd':
123 if (arg >= length)
124 throw new ESException("missing printf argument");
125 formatInteger(result, eval.getArg(arg++).toNum(),
126 width, prec, flags, 10);
127 break;
128
129 case 'o':
130 if (arg >= length)
131 throw new ESException("missing printf argument");
132 formatInteger(result, eval.getArg(arg++).toNum(),
133 width, prec, flags, 8);
134 break;
135
136 case 'X':
137 flags |= BIG;
138 case 'x':
139 if (arg >= length)
140 throw new ESException("missing printf argument");
141 formatInteger(result, eval.getArg(arg++).toNum(),
142 width, prec, flags, 16);
143 break;
144
145 case 'E':
146 case 'G':
147 flags |= BIG;
148 case 'f':
149 case 'e':
150 case 'g':
151 if (arg >= length)
152 throw new ESException("missing printf argument");
153 formatDouble(result, eval.getArg(arg++).toNum(),
154 width, prec, flags, ch);
155 break;
156
157 case 'c':
158 if (arg >= length)
159 throw new ESException("missing printf argument");
160 formatChar(result, (int) eval.getArg(arg++).toNum(), width, flags);
161 break;
162
163 case 's':
164 if (arg >= length)
165 throw new ESException("missing printf argument");
166 formatString(result, eval.getArg(arg++).toStr(),
167 prec, width, flags);
168 break;
169
170 default:
171 fixBits(result, format, start, i + 1);
172 break;
173 }
174 }
175
176 return result;
177 }
178
179 private static void formatDouble(CharBuffer cb, double value,
180 int prec, int flags, int type)
181 {
182 String raw = Double.toString(value);
183 int expt = 0;
184 int i = 0;
185 CharBuffer digits = new CharBuffer();
186 int ch = raw.charAt(i);
187 boolean seenDigit = false;
188
189 for (; i < raw.length(); i++) {
191 if ((ch = raw.charAt(i)) == '.' || ch == 'e' || ch == 'E')
192 break;
193 else if (! seenDigit && ch == '0') {
194 }
195 else {
196 seenDigit = true;
197 digits.append((char) ch);
198 expt++;
199 }
200 }
201
202 if (ch == '.')
203 i++;
204
205 for (; i < raw.length(); i++) {
206 ch = raw.charAt(i);
207
208 if (! seenDigit && ch == '0') {
209 expt--;
210 } else if (ch >= '0' && ch <= '9') {
211 digits.append((char) ch);
212 seenDigit = true;
213 }
214 else {
215 int sign = 1;
216 i++;
217 if ((ch = raw.charAt(i)) == '+') {
218 i++;
219 }
220 else if (ch == '-') {
221 i++;
222 sign = -1;
223 }
224
225 int e = 0;
226 for (; i < raw.length() && (ch = raw.charAt(i)) >= '0' && ch <= '9';
227 i++) {
228 e = 10 * e + ch - '0';
229 }
230
231 expt += sign * e;
232 break;
233 }
234 }
235
236 if (! seenDigit)
237 expt = 1;
238
239 while (digits.length() > 0 && digits.charAt(digits.length() - 1) == '0')
240 digits.setLength(digits.length() - 1);
241
242 if (type == 'f') {
243 if (roundDigits(digits, expt + prec)) {
244 expt++;
245 }
246
247 formatFixed(cb, digits, expt, prec, flags);
248 }
249 else if (type == 'e' || type == 'E') {
250 if (roundDigits(digits, prec + 1))
251 expt++;
252
253 formatExpt(cb, digits, expt, prec, flags);
254 }
255 else {
256 if (roundDigits(digits, prec))
257 expt++;
258
259 if (expt < -3 || expt > prec)
260 formatExpt(cb, digits, expt, prec - 1, flags|NO_TRAIL_ZERO);
261 else
262 formatFixed(cb, digits, expt, prec - expt, flags|NO_TRAIL_ZERO);
263 }
264 }
265
266 private static void formatDouble(CharBuffer cb, double value,
267 int width, int prec, int flags,
268 int type)
269 {
270 if (prec < 0)
271 prec = 6;
272
273 int offset = cb.length();
274
275 if ((flags & ZERO_FILL) != 0 &&
276 (value < 0 || (flags & (POS_PLUS|POS_SPACE)) != 0)) {
277 offset++;
278 width--;
279 }
280
281 if (value < 0) {
282 cb.append((char) '-');
283 value = -value;
284 } else if ((flags & POS_PLUS) != 0) {
285 cb.append((char) '+');
286 } else if ((flags & POS_SPACE) != 0) {
287 cb.append((char) ' ');
288 }
289
290 formatDouble(cb, value, prec, flags, type);
291
292 width -= cb.length() - offset;
293
294 for (int i = 0; i < width; i++) {
295 if ((flags & LALIGN) != 0)
296 cb.append(' ');
297 else
298 cb.insert(offset, (flags & ZERO_FILL) == 0 ? ' ' : '0');
299 }
300 }
301
302 private static boolean roundDigits(CharBuffer digits, int len)
303 {
304 if (len < 0 || digits.length() <= len)
305 return false;
306
307 int value = digits.charAt(len);
308 if (value < '5')
309 return false;
310
311 for (int i = len - 1; i >= 0; i--) {
312 int ch = digits.charAt(i);
313
314 if (ch != '9') {
315 digits.setCharAt(i, (char) (ch + 1));
316 return false;
317 }
318 digits.setCharAt(i, '0');
319 }
320
321 digits.insert(0, '1');
322
323 return true;
324 }
325
326 private static void formatFixed(CharBuffer cb, CharBuffer digits,
327 int expt, int prec, int flags)
328 {
329 int i = 0;
330 int origExpt = expt;
331
332 for (; expt > 0; expt--) {
333 if (i < digits.length())
334 cb.append((char) digits.charAt(i++));
335 else
336 cb.append('0');
337 }
338
339 if (origExpt <= 0) cb.append('0');
341
342 if (prec > 0 || (flags & ALT) != 0)
343 cb.append('.');
344
345 for (; expt < 0 && prec > 0; expt++) {
346 cb.append('0');
347 prec--;
348 }
349
350 for (; prec > 0 && i < digits.length(); i++) {
351 cb.append(digits.charAt(i));
352 prec--;
353 }
354
355 for (; prec > 0 && (flags & (NO_TRAIL_ZERO|ALT)) != NO_TRAIL_ZERO; prec--)
356 cb.append('0');
357 }
358
359 private static void formatExpt(CharBuffer cb, CharBuffer digits,
360 int expt, int prec, int flags)
361 {
362 if (digits.length() == 0)
363 cb.append('0');
364 else
365 cb.append((char) digits.charAt(0));
366
367 if (prec > 0 || (flags & ALT) != 0)
368 cb.append('.');
369
370 for (int i = 1; i < digits.length(); i++) {
371 if (prec > 0)
372 cb.append((char) digits.charAt(i));
373 prec--;
374 }
375
376 for (; prec > 0 && (flags & (NO_TRAIL_ZERO|ALT)) != NO_TRAIL_ZERO; prec--)
377 cb.append('0');
378
379 if ((flags & BIG) != 0)
380 cb.append('E');
381 else
382 cb.append('e');
383
384 formatInteger(cb, expt - 1, 0, 2, POS_PLUS, 10);
385 }
386
387 private static void formatInteger(CharBuffer cb, double dvalue,
388 int width, int prec, int flags, int radix)
389 {
390 boolean isBig = (flags & BIG) != 0;
391 int begin = cb.length();
392
393 long value;
394 if (dvalue > 0)
395 value = (long) (dvalue + 0.5);
396 else
397 value = (long) (dvalue - 0.5);
398
399 if (value < 0 && radix == 10) {
400 cb.append((char) '-');
401 value = -value;
402 } else if (value >= 0 && radix == 10 && (flags & POS_PLUS) != 0)
403 cb.append((char) '+');
404 else if (value >= 0 && radix == 10 && (flags & POS_SPACE) != 0)
405 cb.append((char) ' ');
406 else if (value < 0)
407 value &= 0xffffffffL;
408 else if (radix == 8 && (flags & ALT) != 0 && value != 0)
409 cb.append('0');
410 else if (radix == 16 && (flags & ALT) != 0)
411 cb.append((flags & BIG) == 0 ? "0x" : "0X");
412
413 if ((flags & ZERO_FILL) != 0) {
414 width -= cb.length() - begin;
415 begin = cb.length();
416 }
417
418 int offset = cb.length();
419 int len = 0;
420 while (value != 0) {
421 len++;
422 cb.insert(offset, (isBig ? bigDigits : digits)[(int) (value % radix)]);
423 value /= radix;
424 }
425
426 for (int i = 0; i < prec - len; i++)
427 cb.insert(offset, '0');
428 if (len == 0 && prec == 0)
429 cb.insert(offset, '0');
430
431 width -= cb.length() - begin;
432 for (; width > 0; width--) {
433 if ((flags & LALIGN) != 0)
434 cb.append(' ');
435 else if ((flags & ZERO_FILL) != 0 && prec < 0)
436 cb.insert(begin, '0');
437 else
438 cb.insert(begin, ' ');
439 }
440
441 if (cb.length() == begin)
442 cb.append('0');
443 }
444
445 private static void formatChar(CharBuffer cb, int ch, int width, int flags)
446 {
447 int offset = cb.length();
448
449 cb.append((char) ch);
450
451 if ((flags & LALIGN) == 0) {
452 for (int i = 0; i < width - 1; i++)
453 cb.insert(offset, (char) ' ');
454 } else {
455 for (int i = 0; i < width - 1; i++)
456 cb.append((char) ' ');
457 }
458 }
459
460 private static void formatString(CharBuffer cb, ESString string,
461 int prec, int width, int flags)
462 {
463 int offset = cb.length();
464
465 if (prec < 0)
466 prec = Integer.MAX_VALUE;
467
468 for (int i = 0; i < string.length() && i < prec; i++) {
469 width--;
470 cb.append(string.charAt(i));
471 }
472
473 if ((flags & LALIGN) == 0) {
474 for (int i = 0; i < width; i++)
475 cb.insert(offset, (char) ' ');
476 } else {
477 for (int i = 0; i < width; i++)
478 cb.append((char) ' ');
479 }
480 }
481
482 private static void fixBits(CharBuffer cb, ESString format, int s, int i)
483 {
484 for (; s < i; s++)
485 cb.append((char) format.charAt(s));
486 }
487 }
488 |
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