1// © 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3/*
4 **********************************************************************
5 * Copyright (C) 1999-2011, International Business Machines
6 * Corporation and others. All Rights Reserved.
7 **********************************************************************
8 * Date Name Description
9 * 11/17/99 aliu Creation.
10 **********************************************************************
11 */
12
13#include "unicode/utypes.h"
14
15#if !UCONFIG_NO_TRANSLITERATION
16
17#include "unicode/unistr.h"
18#include "unicode/uniset.h"
19#include "unicode/utf16.h"
20#include "rbt_set.h"
21#include "rbt_rule.h"
22#include "cmemory.h"
23#include "putilimp.h"
24
25U_CDECL_BEGIN
26static void U_CALLCONV _deleteRule(void *rule) {
27 delete (icu::TransliterationRule *)rule;
28}
29U_CDECL_END
30
31//----------------------------------------------------------------------
32// BEGIN Debugging support
33//----------------------------------------------------------------------
34
35// #define DEBUG_RBT
36
37#ifdef DEBUG_RBT
38#include <stdio.h>
39#include "charstr.h"
40
41/**
42 * @param appendTo result is appended to this param.
43 * @param input the string being transliterated
44 * @param pos the index struct
45 */
46static UnicodeString& _formatInput(UnicodeString &appendTo,
47 const UnicodeString& input,
48 const UTransPosition& pos) {
49 // Output a string of the form aaa{bbb|ccc|ddd}eee, where
50 // the {} indicate the context start and limit, and the ||
51 // indicate the start and limit.
52 if (0 <= pos.contextStart &&
53 pos.contextStart <= pos.start &&
54 pos.start <= pos.limit &&
55 pos.limit <= pos.contextLimit &&
56 pos.contextLimit <= input.length()) {
57
58 UnicodeString a, b, c, d, e;
59 input.extractBetween(0, pos.contextStart, a);
60 input.extractBetween(pos.contextStart, pos.start, b);
61 input.extractBetween(pos.start, pos.limit, c);
62 input.extractBetween(pos.limit, pos.contextLimit, d);
63 input.extractBetween(pos.contextLimit, input.length(), e);
64 appendTo.append(a).append((UChar)123/*{*/).append(b).
65 append((UChar)124/*|*/).append(c).append((UChar)124/*|*/).append(d).
66 append((UChar)125/*}*/).append(e);
67 } else {
68 appendTo.append("INVALID UTransPosition");
69 //appendTo.append((UnicodeString)"INVALID UTransPosition {cs=" +
70 // pos.contextStart + ", s=" + pos.start + ", l=" +
71 // pos.limit + ", cl=" + pos.contextLimit + "} on " +
72 // input);
73 }
74 return appendTo;
75}
76
77// Append a hex string to the target
78UnicodeString& _appendHex(uint32_t number,
79 int32_t digits,
80 UnicodeString& target) {
81 static const UChar digitString[] = {
82 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
83 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0
84 };
85 while (digits--) {
86 target += digitString[(number >> (digits*4)) & 0xF];
87 }
88 return target;
89}
90
91// Replace nonprintable characters with unicode escapes
92UnicodeString& _escape(const UnicodeString &source,
93 UnicodeString &target) {
94 for (int32_t i = 0; i < source.length(); ) {
95 UChar32 ch = source.char32At(i);
96 i += U16_LENGTH(ch);
97 if (ch < 0x09 || (ch > 0x0A && ch < 0x20)|| ch > 0x7E) {
98 if (ch <= 0xFFFF) {
99 target += "\\u";
100 _appendHex(ch, 4, target);
101 } else {
102 target += "\\U";
103 _appendHex(ch, 8, target);
104 }
105 } else {
106 target += ch;
107 }
108 }
109 return target;
110}
111
112inline void _debugOut(const char* msg, TransliterationRule* rule,
113 const Replaceable& theText, UTransPosition& pos) {
114 UnicodeString buf(msg, "");
115 if (rule) {
116 UnicodeString r;
117 rule->toRule(r, TRUE);
118 buf.append((UChar)32).append(r);
119 }
120 buf.append(UnicodeString(" => ", ""));
121 UnicodeString* text = (UnicodeString*)&theText;
122 _formatInput(buf, *text, pos);
123 UnicodeString esc;
124 _escape(buf, esc);
125 CharString cbuf(esc);
126 printf("%s\n", (const char*) cbuf);
127}
128
129#else
130#define _debugOut(msg, rule, theText, pos)
131#endif
132
133//----------------------------------------------------------------------
134// END Debugging support
135//----------------------------------------------------------------------
136
137// Fill the precontext and postcontext with the patterns of the rules
138// that are masking one another.
139static void maskingError(const icu::TransliterationRule& rule1,
140 const icu::TransliterationRule& rule2,
141 UParseError& parseError) {
142 icu::UnicodeString r;
143 int32_t len;
144
145 parseError.line = parseError.offset = -1;
146
147 // for pre-context
148 rule1.toRule(r, FALSE);
149 len = uprv_min(r.length(), U_PARSE_CONTEXT_LEN-1);
150 r.extract(0, len, parseError.preContext);
151 parseError.preContext[len] = 0;
152
153 //for post-context
154 r.truncate(0);
155 rule2.toRule(r, FALSE);
156 len = uprv_min(r.length(), U_PARSE_CONTEXT_LEN-1);
157 r.extract(0, len, parseError.postContext);
158 parseError.postContext[len] = 0;
159}
160
161U_NAMESPACE_BEGIN
162
163/**
164 * Construct a new empty rule set.
165 */
166TransliterationRuleSet::TransliterationRuleSet(UErrorCode& status) : UMemory() {
167 ruleVector = new UVector(&_deleteRule, NULL, status);
168 if (U_FAILURE(status)) {
169 return;
170 }
171 if (ruleVector == NULL) {
172 status = U_MEMORY_ALLOCATION_ERROR;
173 }
174 rules = NULL;
175 maxContextLength = 0;
176}
177
178/**
179 * Copy constructor.
180 */
181TransliterationRuleSet::TransliterationRuleSet(const TransliterationRuleSet& other) :
182 UMemory(other),
183 ruleVector(0),
184 rules(0),
185 maxContextLength(other.maxContextLength) {
186
187 int32_t i, len;
188 uprv_memcpy(index, other.index, sizeof(index));
189 UErrorCode status = U_ZERO_ERROR;
190 ruleVector = new UVector(&_deleteRule, NULL, status);
191 if (other.ruleVector != 0 && ruleVector != 0 && U_SUCCESS(status)) {
192 len = other.ruleVector->size();
193 for (i=0; i<len && U_SUCCESS(status); ++i) {
194 TransliterationRule *tempTranslitRule = new TransliterationRule(*(TransliterationRule*)other.ruleVector->elementAt(i));
195 // Null pointer test
196 if (tempTranslitRule == NULL) {
197 status = U_MEMORY_ALLOCATION_ERROR;
198 break;
199 }
200 ruleVector->addElement(tempTranslitRule, status);
201 if (U_FAILURE(status)) {
202 break;
203 }
204 }
205 }
206 if (other.rules != 0 && U_SUCCESS(status)) {
207 UParseError p;
208 freeze(p, status);
209 }
210}
211
212/**
213 * Destructor.
214 */
215TransliterationRuleSet::~TransliterationRuleSet() {
216 delete ruleVector; // This deletes the contained rules
217 uprv_free(rules);
218}
219
220void TransliterationRuleSet::setData(const TransliterationRuleData* d) {
221 /**
222 * We assume that the ruleset has already been frozen.
223 */
224 int32_t len = index[256]; // see freeze()
225 for (int32_t i=0; i<len; ++i) {
226 rules[i]->setData(d);
227 }
228}
229
230/**
231 * Return the maximum context length.
232 * @return the length of the longest preceding context.
233 */
234int32_t TransliterationRuleSet::getMaximumContextLength(void) const {
235 return maxContextLength;
236}
237
238/**
239 * Add a rule to this set. Rules are added in order, and order is
240 * significant. The last call to this method must be followed by
241 * a call to <code>freeze()</code> before the rule set is used.
242 *
243 * <p>If freeze() has already been called, calling addRule()
244 * unfreezes the rules, and freeze() must be called again.
245 *
246 * @param adoptedRule the rule to add
247 */
248void TransliterationRuleSet::addRule(TransliterationRule* adoptedRule,
249 UErrorCode& status) {
250 if (U_FAILURE(status)) {
251 delete adoptedRule;
252 return;
253 }
254 ruleVector->addElement(adoptedRule, status);
255
256 int32_t len;
257 if ((len = adoptedRule->getContextLength()) > maxContextLength) {
258 maxContextLength = len;
259 }
260
261 uprv_free(rules);
262 rules = 0;
263}
264
265/**
266 * Check this for masked rules and index it to optimize performance.
267 * The sequence of operations is: (1) add rules to a set using
268 * <code>addRule()</code>; (2) freeze the set using
269 * <code>freeze()</code>; (3) use the rule set. If
270 * <code>addRule()</code> is called after calling this method, it
271 * invalidates this object, and this method must be called again.
272 * That is, <code>freeze()</code> may be called multiple times,
273 * although for optimal performance it shouldn't be.
274 */
275void TransliterationRuleSet::freeze(UParseError& parseError,UErrorCode& status) {
276 /* Construct the rule array and index table. We reorder the
277 * rules by sorting them into 256 bins. Each bin contains all
278 * rules matching the index value for that bin. A rule
279 * matches an index value if string whose first key character
280 * has a low byte equal to the index value can match the rule.
281 *
282 * Each bin contains zero or more rules, in the same order
283 * they were found originally. However, the total rules in
284 * the bins may exceed the number in the original vector,
285 * since rules that have a variable as their first key
286 * character will generally fall into more than one bin.
287 *
288 * That is, each bin contains all rules that either have that
289 * first index value as their first key character, or have
290 * a set containing the index value as their first character.
291 */
292 int32_t n = ruleVector->size();
293 int32_t j;
294 int16_t x;
295 UVector v(2*n, status); // heuristic; adjust as needed
296
297 if (U_FAILURE(status)) {
298 return;
299 }
300
301 /* Precompute the index values. This saves a LOT of time.
302 * Be careful not to call malloc(0).
303 */
304 int16_t* indexValue = (int16_t*) uprv_malloc( sizeof(int16_t) * (n > 0 ? n : 1) );
305 /* test for NULL */
306 if (indexValue == 0) {
307 status = U_MEMORY_ALLOCATION_ERROR;
308 return;
309 }
310 for (j=0; j<n; ++j) {
311 TransliterationRule* r = (TransliterationRule*) ruleVector->elementAt(j);
312 indexValue[j] = r->getIndexValue();
313 }
314 for (x=0; x<256; ++x) {
315 index[x] = v.size();
316 for (j=0; j<n; ++j) {
317 if (indexValue[j] >= 0) {
318 if (indexValue[j] == x) {
319 v.addElement(ruleVector->elementAt(j), status);
320 }
321 } else {
322 // If the indexValue is < 0, then the first key character is
323 // a set, and we must use the more time-consuming
324 // matchesIndexValue check. In practice this happens
325 // rarely, so we seldom tread this code path.
326 TransliterationRule* r = (TransliterationRule*) ruleVector->elementAt(j);
327 if (r->matchesIndexValue((uint8_t)x)) {
328 v.addElement(r, status);
329 }
330 }
331 }
332 }
333 uprv_free(indexValue);
334 index[256] = v.size();
335
336 /* Freeze things into an array.
337 */
338 uprv_free(rules); // Contains alias pointers
339
340 /* You can't do malloc(0)! */
341 if (v.size() == 0) {
342 rules = NULL;
343 return;
344 }
345 rules = (TransliterationRule **)uprv_malloc(v.size() * sizeof(TransliterationRule *));
346 /* test for NULL */
347 if (rules == 0) {
348 status = U_MEMORY_ALLOCATION_ERROR;
349 return;
350 }
351 for (j=0; j<v.size(); ++j) {
352 rules[j] = (TransliterationRule*) v.elementAt(j);
353 }
354
355 // TODO Add error reporting that indicates the rules that
356 // are being masked.
357 //UnicodeString errors;
358
359 /* Check for masking. This is MUCH faster than our old check,
360 * which was each rule against each following rule, since we
361 * only have to check for masking within each bin now. It's
362 * 256*O(n2^2) instead of O(n1^2), where n1 is the total rule
363 * count, and n2 is the per-bin rule count. But n2<<n1, so
364 * it's a big win.
365 */
366 for (x=0; x<256; ++x) {
367 for (j=index[x]; j<index[x+1]-1; ++j) {
368 TransliterationRule* r1 = rules[j];
369 for (int32_t k=j+1; k<index[x+1]; ++k) {
370 TransliterationRule* r2 = rules[k];
371 if (r1->masks(*r2)) {
372//| if (errors == null) {
373//| errors = new StringBuffer();
374//| } else {
375//| errors.append("\n");
376//| }
377//| errors.append("Rule " + r1 + " masks " + r2);
378 status = U_RULE_MASK_ERROR;
379 maskingError(*r1, *r2, parseError);
380 return;
381 }
382 }
383 }
384 }
385
386 //if (errors != null) {
387 // throw new IllegalArgumentException(errors.toString());
388 //}
389}
390
391/**
392 * Transliterate the given text with the given UTransPosition
393 * indices. Return TRUE if the transliteration should continue
394 * or FALSE if it should halt (because of a U_PARTIAL_MATCH match).
395 * Note that FALSE is only ever returned if isIncremental is TRUE.
396 * @param text the text to be transliterated
397 * @param pos the position indices, which will be updated
398 * @param incremental if TRUE, assume new text may be inserted
399 * at index.limit, and return FALSE if thre is a partial match.
400 * @return TRUE unless a U_PARTIAL_MATCH has been obtained,
401 * indicating that transliteration should stop until more text
402 * arrives.
403 */
404UBool TransliterationRuleSet::transliterate(Replaceable& text,
405 UTransPosition& pos,
406 UBool incremental) {
407 int16_t indexByte = (int16_t) (text.char32At(pos.start) & 0xFF);
408 for (int32_t i=index[indexByte]; i<index[indexByte+1]; ++i) {
409 UMatchDegree m = rules[i]->matchAndReplace(text, pos, incremental);
410 switch (m) {
411 case U_MATCH:
412 _debugOut("match", rules[i], text, pos);
413 return TRUE;
414 case U_PARTIAL_MATCH:
415 _debugOut("partial match", rules[i], text, pos);
416 return FALSE;
417 default: /* Ram: added default to make GCC happy */
418 break;
419 }
420 }
421 // No match or partial match from any rule
422 pos.start += U16_LENGTH(text.char32At(pos.start));
423 _debugOut("no match", NULL, text, pos);
424 return TRUE;
425}
426
427/**
428 * Create rule strings that represents this rule set.
429 */
430UnicodeString& TransliterationRuleSet::toRules(UnicodeString& ruleSource,
431 UBool escapeUnprintable) const {
432 int32_t i;
433 int32_t count = ruleVector->size();
434 ruleSource.truncate(0);
435 for (i=0; i<count; ++i) {
436 if (i != 0) {
437 ruleSource.append((UChar) 0x000A /*\n*/);
438 }
439 TransliterationRule *r =
440 (TransliterationRule*) ruleVector->elementAt(i);
441 r->toRule(ruleSource, escapeUnprintable);
442 }
443 return ruleSource;
444}
445
446/**
447 * Return the set of all characters that may be modified
448 * (getTarget=false) or emitted (getTarget=true) by this set.
449 */
450UnicodeSet& TransliterationRuleSet::getSourceTargetSet(UnicodeSet& result,
451 UBool getTarget) const
452{
453 result.clear();
454 int32_t count = ruleVector->size();
455 for (int32_t i=0; i<count; ++i) {
456 TransliterationRule* r =
457 (TransliterationRule*) ruleVector->elementAt(i);
458 if (getTarget) {
459 r->addTargetSetTo(result);
460 } else {
461 r->addSourceSetTo(result);
462 }
463 }
464 return result;
465}
466
467U_NAMESPACE_END
468
469#endif /* #if !UCONFIG_NO_TRANSLITERATION */
470