1 /*
2 **********************************************************************
3 * Copyright (C) 1999-2007, International Business Machines
4 * Corporation and others. All Rights Reserved.
5 **********************************************************************
6 * Date Name Description
7 * 11/17/99 aliu Creation.
8 **********************************************************************
9 */
10
11 #include "unicode/utypes.h"
12
13 #if !UCONFIG_NO_TRANSLITERATION
14
15 #include "unicode/unistr.h"
16 #include "unicode/uniset.h"
17 #include "rbt_set.h"
18 #include "rbt_rule.h"
19 #include "cmemory.h"
20 #include "putilimp.h"
21
22 U_CDECL_BEGIN
_deleteRule(void * rule)23 static void U_CALLCONV _deleteRule(void *rule) {
24 delete (U_NAMESPACE_QUALIFIER TransliterationRule *)rule;
25 }
26 U_CDECL_END
27
28 //----------------------------------------------------------------------
29 // BEGIN Debugging support
30 //----------------------------------------------------------------------
31
32 // #define DEBUG_RBT
33
34 #ifdef DEBUG_RBT
35 #include <stdio.h>
36 #include "charstr.h"
37
38 /**
39 * @param appendTo result is appended to this param.
40 * @param input the string being transliterated
41 * @param pos the index struct
42 */
_formatInput(UnicodeString & appendTo,const UnicodeString & input,const UTransPosition & pos)43 static UnicodeString& _formatInput(UnicodeString &appendTo,
44 const UnicodeString& input,
45 const UTransPosition& pos) {
46 // Output a string of the form aaa{bbb|ccc|ddd}eee, where
47 // the {} indicate the context start and limit, and the ||
48 // indicate the start and limit.
49 if (0 <= pos.contextStart &&
50 pos.contextStart <= pos.start &&
51 pos.start <= pos.limit &&
52 pos.limit <= pos.contextLimit &&
53 pos.contextLimit <= input.length()) {
54
55 UnicodeString a, b, c, d, e;
56 input.extractBetween(0, pos.contextStart, a);
57 input.extractBetween(pos.contextStart, pos.start, b);
58 input.extractBetween(pos.start, pos.limit, c);
59 input.extractBetween(pos.limit, pos.contextLimit, d);
60 input.extractBetween(pos.contextLimit, input.length(), e);
61 appendTo.append(a).append((UChar)123/*{*/).append(b).
62 append((UChar)124/*|*/).append(c).append((UChar)124/*|*/).append(d).
63 append((UChar)125/*}*/).append(e);
64 } else {
65 appendTo.append("INVALID UTransPosition");
66 //appendTo.append((UnicodeString)"INVALID UTransPosition {cs=" +
67 // pos.contextStart + ", s=" + pos.start + ", l=" +
68 // pos.limit + ", cl=" + pos.contextLimit + "} on " +
69 // input);
70 }
71 return appendTo;
72 }
73
74 // Append a hex string to the target
_appendHex(uint32_t number,int32_t digits,UnicodeString & target)75 UnicodeString& _appendHex(uint32_t number,
76 int32_t digits,
77 UnicodeString& target) {
78 static const UChar digitString[] = {
79 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
80 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0
81 };
82 while (digits--) {
83 target += digitString[(number >> (digits*4)) & 0xF];
84 }
85 return target;
86 }
87
88 // Replace nonprintable characters with unicode escapes
_escape(const UnicodeString & source,UnicodeString & target)89 UnicodeString& _escape(const UnicodeString &source,
90 UnicodeString &target) {
91 for (int32_t i = 0; i < source.length(); ) {
92 UChar32 ch = source.char32At(i);
93 i += UTF_CHAR_LENGTH(ch);
94 if (ch < 0x09 || (ch > 0x0A && ch < 0x20)|| ch > 0x7E) {
95 if (ch <= 0xFFFF) {
96 target += "\\u";
97 _appendHex(ch, 4, target);
98 } else {
99 target += "\\U";
100 _appendHex(ch, 8, target);
101 }
102 } else {
103 target += ch;
104 }
105 }
106 return target;
107 }
108
_debugOut(const char * msg,TransliterationRule * rule,const Replaceable & theText,UTransPosition & pos)109 inline void _debugOut(const char* msg, TransliterationRule* rule,
110 const Replaceable& theText, UTransPosition& pos) {
111 UnicodeString buf(msg, "");
112 if (rule) {
113 UnicodeString r;
114 rule->toRule(r, TRUE);
115 buf.append((UChar)32).append(r);
116 }
117 buf.append(UnicodeString(" => ", ""));
118 UnicodeString* text = (UnicodeString*)&theText;
119 _formatInput(buf, *text, pos);
120 UnicodeString esc;
121 _escape(buf, esc);
122 CharString cbuf(esc);
123 printf("%s\n", (const char*) cbuf);
124 }
125
126 #else
127 #define _debugOut(msg, rule, theText, pos)
128 #endif
129
130 //----------------------------------------------------------------------
131 // END Debugging support
132 //----------------------------------------------------------------------
133
134 // Fill the precontext and postcontext with the patterns of the rules
135 // that are masking one another.
maskingError(const U_NAMESPACE_QUALIFIER TransliterationRule & rule1,const U_NAMESPACE_QUALIFIER TransliterationRule & rule2,UParseError & parseError)136 static void maskingError(const U_NAMESPACE_QUALIFIER TransliterationRule& rule1,
137 const U_NAMESPACE_QUALIFIER TransliterationRule& rule2,
138 UParseError& parseError) {
139 U_NAMESPACE_QUALIFIER UnicodeString r;
140 int32_t len;
141
142 parseError.line = parseError.offset = -1;
143
144 // for pre-context
145 rule1.toRule(r, FALSE);
146 len = uprv_min(r.length(), U_PARSE_CONTEXT_LEN-1);
147 r.extract(0, len, parseError.preContext);
148 parseError.preContext[len] = 0;
149
150 //for post-context
151 r.truncate(0);
152 rule2.toRule(r, FALSE);
153 len = uprv_min(r.length(), U_PARSE_CONTEXT_LEN-1);
154 r.extract(0, len, parseError.postContext);
155 parseError.postContext[len] = 0;
156 }
157
158 U_NAMESPACE_BEGIN
159
160 /**
161 * Construct a new empty rule set.
162 */
TransliterationRuleSet(UErrorCode & status)163 TransliterationRuleSet::TransliterationRuleSet(UErrorCode& status) : UMemory() {
164 ruleVector = new UVector(&_deleteRule, NULL, status);
165 rules = NULL;
166 maxContextLength = 0;
167 if (ruleVector == NULL) {
168 status = U_MEMORY_ALLOCATION_ERROR;
169 }
170 }
171
172 /**
173 * Copy constructor.
174 */
TransliterationRuleSet(const TransliterationRuleSet & other)175 TransliterationRuleSet::TransliterationRuleSet(const TransliterationRuleSet& other) :
176 UMemory(other),
177 ruleVector(0),
178 rules(0),
179 maxContextLength(other.maxContextLength) {
180
181 int32_t i, len;
182 uprv_memcpy(index, other.index, sizeof(index));
183 UErrorCode status = U_ZERO_ERROR;
184 ruleVector = new UVector(&_deleteRule, NULL, status);
185 if (other.ruleVector != 0 && ruleVector != 0 && U_SUCCESS(status)) {
186 len = other.ruleVector->size();
187 for (i=0; i<len && U_SUCCESS(status); ++i) {
188 ruleVector->addElement(new TransliterationRule(
189 *(TransliterationRule*)other.ruleVector->elementAt(i)), status);
190 }
191 }
192 if (other.rules != 0) {
193 UParseError p;
194 freeze(p, status);
195 }
196 }
197
198 /**
199 * Destructor.
200 */
~TransliterationRuleSet()201 TransliterationRuleSet::~TransliterationRuleSet() {
202 delete ruleVector; // This deletes the contained rules
203 uprv_free(rules);
204 }
205
setData(const TransliterationRuleData * d)206 void TransliterationRuleSet::setData(const TransliterationRuleData* d) {
207 /**
208 * We assume that the ruleset has already been frozen.
209 */
210 int32_t len = index[256]; // see freeze()
211 for (int32_t i=0; i<len; ++i) {
212 rules[i]->setData(d);
213 }
214 }
215
216 /**
217 * Return the maximum context length.
218 * @return the length of the longest preceding context.
219 */
getMaximumContextLength(void) const220 int32_t TransliterationRuleSet::getMaximumContextLength(void) const {
221 return maxContextLength;
222 }
223
224 /**
225 * Add a rule to this set. Rules are added in order, and order is
226 * significant. The last call to this method must be followed by
227 * a call to <code>freeze()</code> before the rule set is used.
228 *
229 * <p>If freeze() has already been called, calling addRule()
230 * unfreezes the rules, and freeze() must be called again.
231 *
232 * @param adoptedRule the rule to add
233 */
addRule(TransliterationRule * adoptedRule,UErrorCode & status)234 void TransliterationRuleSet::addRule(TransliterationRule* adoptedRule,
235 UErrorCode& status) {
236 if (U_FAILURE(status)) {
237 delete adoptedRule;
238 return;
239 }
240 ruleVector->addElement(adoptedRule, status);
241
242 int32_t len;
243 if ((len = adoptedRule->getContextLength()) > maxContextLength) {
244 maxContextLength = len;
245 }
246
247 uprv_free(rules);
248 rules = 0;
249 }
250
251 /**
252 * Check this for masked rules and index it to optimize performance.
253 * The sequence of operations is: (1) add rules to a set using
254 * <code>addRule()</code>; (2) freeze the set using
255 * <code>freeze()</code>; (3) use the rule set. If
256 * <code>addRule()</code> is called after calling this method, it
257 * invalidates this object, and this method must be called again.
258 * That is, <code>freeze()</code> may be called multiple times,
259 * although for optimal performance it shouldn't be.
260 */
freeze(UParseError & parseError,UErrorCode & status)261 void TransliterationRuleSet::freeze(UParseError& parseError,UErrorCode& status) {
262 /* Construct the rule array and index table. We reorder the
263 * rules by sorting them into 256 bins. Each bin contains all
264 * rules matching the index value for that bin. A rule
265 * matches an index value if string whose first key character
266 * has a low byte equal to the index value can match the rule.
267 *
268 * Each bin contains zero or more rules, in the same order
269 * they were found originally. However, the total rules in
270 * the bins may exceed the number in the original vector,
271 * since rules that have a variable as their first key
272 * character will generally fall into more than one bin.
273 *
274 * That is, each bin contains all rules that either have that
275 * first index value as their first key character, or have
276 * a set containing the index value as their first character.
277 */
278 int32_t n = ruleVector->size();
279 int32_t j;
280 int16_t x;
281 UVector v(2*n, status); // heuristic; adjust as needed
282
283 if (U_FAILURE(status)) {
284 return;
285 }
286
287 /* Precompute the index values. This saves a LOT of time.
288 * Be careful not to call malloc(0).
289 */
290 int16_t* indexValue = (int16_t*) uprv_malloc( sizeof(int16_t) * (n > 0 ? n : 1) );
291 /* test for NULL */
292 if (indexValue == 0) {
293 status = U_MEMORY_ALLOCATION_ERROR;
294 return;
295 }
296 for (j=0; j<n; ++j) {
297 TransliterationRule* r = (TransliterationRule*) ruleVector->elementAt(j);
298 indexValue[j] = r->getIndexValue();
299 }
300 for (x=0; x<256; ++x) {
301 index[x] = v.size();
302 for (j=0; j<n; ++j) {
303 if (indexValue[j] >= 0) {
304 if (indexValue[j] == x) {
305 v.addElement(ruleVector->elementAt(j), status);
306 }
307 } else {
308 // If the indexValue is < 0, then the first key character is
309 // a set, and we must use the more time-consuming
310 // matchesIndexValue check. In practice this happens
311 // rarely, so we seldom tread this code path.
312 TransliterationRule* r = (TransliterationRule*) ruleVector->elementAt(j);
313 if (r->matchesIndexValue((uint8_t)x)) {
314 v.addElement(r, status);
315 }
316 }
317 }
318 }
319 uprv_free(indexValue);
320 index[256] = v.size();
321
322 /* Freeze things into an array.
323 */
324 uprv_free(rules); // Contains alias pointers
325
326 /* You can't do malloc(0)! */
327 if (v.size() == 0) {
328 rules = NULL;
329 return;
330 }
331 rules = (TransliterationRule **)uprv_malloc(v.size() * sizeof(TransliterationRule *));
332 /* test for NULL */
333 if (rules == 0) {
334 status = U_MEMORY_ALLOCATION_ERROR;
335 return;
336 }
337 for (j=0; j<v.size(); ++j) {
338 rules[j] = (TransliterationRule*) v.elementAt(j);
339 }
340
341 // TODO Add error reporting that indicates the rules that
342 // are being masked.
343 //UnicodeString errors;
344
345 /* Check for masking. This is MUCH faster than our old check,
346 * which was each rule against each following rule, since we
347 * only have to check for masking within each bin now. It's
348 * 256*O(n2^2) instead of O(n1^2), where n1 is the total rule
349 * count, and n2 is the per-bin rule count. But n2<<n1, so
350 * it's a big win.
351 */
352 for (x=0; x<256; ++x) {
353 for (j=index[x]; j<index[x+1]-1; ++j) {
354 TransliterationRule* r1 = rules[j];
355 for (int32_t k=j+1; k<index[x+1]; ++k) {
356 TransliterationRule* r2 = rules[k];
357 if (r1->masks(*r2)) {
358 //| if (errors == null) {
359 //| errors = new StringBuffer();
360 //| } else {
361 //| errors.append("\n");
362 //| }
363 //| errors.append("Rule " + r1 + " masks " + r2);
364 status = U_RULE_MASK_ERROR;
365 maskingError(*r1, *r2, parseError);
366 return;
367 }
368 }
369 }
370 }
371
372 //if (errors != null) {
373 // throw new IllegalArgumentException(errors.toString());
374 //}
375 }
376
377 /**
378 * Transliterate the given text with the given UTransPosition
379 * indices. Return TRUE if the transliteration should continue
380 * or FALSE if it should halt (because of a U_PARTIAL_MATCH match).
381 * Note that FALSE is only ever returned if isIncremental is TRUE.
382 * @param text the text to be transliterated
383 * @param pos the position indices, which will be updated
384 * @param incremental if TRUE, assume new text may be inserted
385 * at index.limit, and return FALSE if thre is a partial match.
386 * @return TRUE unless a U_PARTIAL_MATCH has been obtained,
387 * indicating that transliteration should stop until more text
388 * arrives.
389 */
transliterate(Replaceable & text,UTransPosition & pos,UBool incremental)390 UBool TransliterationRuleSet::transliterate(Replaceable& text,
391 UTransPosition& pos,
392 UBool incremental) {
393 int16_t indexByte = (int16_t) (text.char32At(pos.start) & 0xFF);
394 for (int32_t i=index[indexByte]; i<index[indexByte+1]; ++i) {
395 UMatchDegree m = rules[i]->matchAndReplace(text, pos, incremental);
396 switch (m) {
397 case U_MATCH:
398 _debugOut("match", rules[i], text, pos);
399 return TRUE;
400 case U_PARTIAL_MATCH:
401 _debugOut("partial match", rules[i], text, pos);
402 return FALSE;
403 default: /* Ram: added default to make GCC happy */
404 break;
405 }
406 }
407 // No match or partial match from any rule
408 pos.start += UTF_CHAR_LENGTH(text.char32At(pos.start));
409 _debugOut("no match", NULL, text, pos);
410 return TRUE;
411 }
412
413 /**
414 * Create rule strings that represents this rule set.
415 */
toRules(UnicodeString & ruleSource,UBool escapeUnprintable) const416 UnicodeString& TransliterationRuleSet::toRules(UnicodeString& ruleSource,
417 UBool escapeUnprintable) const {
418 int32_t i;
419 int32_t count = ruleVector->size();
420 ruleSource.truncate(0);
421 for (i=0; i<count; ++i) {
422 if (i != 0) {
423 ruleSource.append((UChar) 0x000A /*\n*/);
424 }
425 TransliterationRule *r =
426 (TransliterationRule*) ruleVector->elementAt(i);
427 r->toRule(ruleSource, escapeUnprintable);
428 }
429 return ruleSource;
430 }
431
432 /**
433 * Return the set of all characters that may be modified
434 * (getTarget=false) or emitted (getTarget=true) by this set.
435 */
getSourceTargetSet(UnicodeSet & result,UBool getTarget) const436 UnicodeSet& TransliterationRuleSet::getSourceTargetSet(UnicodeSet& result,
437 UBool getTarget) const
438 {
439 result.clear();
440 int32_t count = ruleVector->size();
441 for (int32_t i=0; i<count; ++i) {
442 TransliterationRule* r =
443 (TransliterationRule*) ruleVector->elementAt(i);
444 if (getTarget) {
445 r->addTargetSetTo(result);
446 } else {
447 r->addSourceSetTo(result);
448 }
449 }
450 return result;
451 }
452
453 U_NAMESPACE_END
454
455 #endif /* #if !UCONFIG_NO_TRANSLITERATION */
456