intl/icu/source/common/ucnvsel.cpp@6474c204b198
intl/icu/source/common/ucnvsel.cpp
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 /*
2 *******************************************************************************
3 *
4 * Copyright (C) 2008-2011, International Business Machines
5 * Corporation, Google and others. All Rights Reserved.
6 *
7 *******************************************************************************
8 */
9 // Author : eldawy@google.com (Mohamed Eldawy)
10 // ucnvsel.cpp
11 //
12 // Purpose: To generate a list of encodings capable of handling
13 // a given Unicode text
14 //
15 // Started 09-April-2008
17 /**
18 * \file
19 *
20 * This is an implementation of an encoding selector.
21 * The goal is, given a unicode string, find the encodings
22 * this string can be mapped to. To make processing faster
23 * a trie is built when you call ucnvsel_open() that
24 * stores all encodings a codepoint can map to
25 */
27 #include "unicode/ucnvsel.h"
29 #if !UCONFIG_NO_CONVERSION
31 #include <string.h>
33 #include "unicode/uchar.h"
34 #include "unicode/uniset.h"
35 #include "unicode/ucnv.h"
36 #include "unicode/ustring.h"
37 #include "unicode/uchriter.h"
38 #include "utrie2.h"
39 #include "propsvec.h"
40 #include "uassert.h"
41 #include "ucmndata.h"
42 #include "uenumimp.h"
43 #include "cmemory.h"
44 #include "cstring.h"
46 U_NAMESPACE_USE
48 struct UConverterSelector {
49 UTrie2 *trie; // 16 bit trie containing offsets into pv
50 uint32_t* pv; // table of bits!
51 int32_t pvCount;
52 char** encodings; // which encodings did user ask to use?
53 int32_t encodingsCount;
54 int32_t encodingStrLength;
55 uint8_t* swapped;
56 UBool ownPv, ownEncodingStrings;
57 };
59 static void generateSelectorData(UConverterSelector* result,
60 UPropsVectors *upvec,
61 const USet* excludedCodePoints,
62 const UConverterUnicodeSet whichSet,
63 UErrorCode* status) {
64 if (U_FAILURE(*status)) {
65 return;
66 }
68 int32_t columns = (result->encodingsCount+31)/32;
70 // set errorValue to all-ones
71 for (int32_t col = 0; col < columns; col++) {
72 upvec_setValue(upvec, UPVEC_ERROR_VALUE_CP, UPVEC_ERROR_VALUE_CP,
73 col, ~0, ~0, status);
74 }
76 for (int32_t i = 0; i < result->encodingsCount; ++i) {
77 uint32_t mask;
78 uint32_t column;
79 int32_t item_count;
80 int32_t j;
81 UConverter* test_converter = ucnv_open(result->encodings[i], status);
82 if (U_FAILURE(*status)) {
83 return;
84 }
85 USet* unicode_point_set;
86 unicode_point_set = uset_open(1, 0); // empty set
88 ucnv_getUnicodeSet(test_converter, unicode_point_set,
89 whichSet, status);
90 if (U_FAILURE(*status)) {
91 ucnv_close(test_converter);
92 return;
93 }
95 column = i / 32;
96 mask = 1 << (i%32);
97 // now iterate over intervals on set i!
98 item_count = uset_getItemCount(unicode_point_set);
100 for (j = 0; j < item_count; ++j) {
101 UChar32 start_char;
102 UChar32 end_char;
103 UErrorCode smallStatus = U_ZERO_ERROR;
104 uset_getItem(unicode_point_set, j, &start_char, &end_char, NULL, 0,
105 &smallStatus);
106 if (U_FAILURE(smallStatus)) {
107 // this will be reached for the converters that fill the set with
108 // strings. Those should be ignored by our system
109 } else {
110 upvec_setValue(upvec, start_char, end_char, column, ~0, mask,
111 status);
112 }
113 }
114 ucnv_close(test_converter);
115 uset_close(unicode_point_set);
116 if (U_FAILURE(*status)) {
117 return;
118 }
119 }
121 // handle excluded encodings! Simply set their values to all 1's in the upvec
122 if (excludedCodePoints) {
123 int32_t item_count = uset_getItemCount(excludedCodePoints);
124 for (int32_t j = 0; j < item_count; ++j) {
125 UChar32 start_char;
126 UChar32 end_char;
128 uset_getItem(excludedCodePoints, j, &start_char, &end_char, NULL, 0,
129 status);
130 for (int32_t col = 0; col < columns; col++) {
131 upvec_setValue(upvec, start_char, end_char, col, ~0, ~0,
132 status);
133 }
134 }
135 }
137 // alright. Now, let's put things in the same exact form you'd get when you
138 // unserialize things.
139 result->trie = upvec_compactToUTrie2WithRowIndexes(upvec, status);
140 result->pv = upvec_cloneArray(upvec, &result->pvCount, NULL, status);
141 result->pvCount *= columns; // number of uint32_t = rows * columns
142 result->ownPv = TRUE;
143 }
145 /* open a selector. If converterListSize is 0, build for all converters.
146 If excludedCodePoints is NULL, don't exclude any codepoints */
147 U_CAPI UConverterSelector* U_EXPORT2
148 ucnvsel_open(const char* const* converterList, int32_t converterListSize,
149 const USet* excludedCodePoints,
150 const UConverterUnicodeSet whichSet, UErrorCode* status) {
151 // check if already failed
152 if (U_FAILURE(*status)) {
153 return NULL;
154 }
155 // ensure args make sense!
156 if (converterListSize < 0 || (converterList == NULL && converterListSize != 0)) {
157 *status = U_ILLEGAL_ARGUMENT_ERROR;
158 return NULL;
159 }
161 // allocate a new converter
162 LocalUConverterSelectorPointer newSelector(
163 (UConverterSelector*)uprv_malloc(sizeof(UConverterSelector)));
164 if (newSelector.isNull()) {
165 *status = U_MEMORY_ALLOCATION_ERROR;
166 return NULL;
167 }
168 uprv_memset(newSelector.getAlias(), 0, sizeof(UConverterSelector));
170 if (converterListSize == 0) {
171 converterList = NULL;
172 converterListSize = ucnv_countAvailable();
173 }
174 newSelector->encodings =
175 (char**)uprv_malloc(converterListSize * sizeof(char*));
176 if (!newSelector->encodings) {
177 *status = U_MEMORY_ALLOCATION_ERROR;
178 return NULL;
179 }
180 newSelector->encodings[0] = NULL; // now we can call ucnvsel_close()
182 // make a backup copy of the list of converters
183 int32_t totalSize = 0;
184 int32_t i;
185 for (i = 0; i < converterListSize; i++) {
186 totalSize +=
187 (int32_t)uprv_strlen(converterList != NULL ? converterList[i] : ucnv_getAvailableName(i)) + 1;
188 }
189 // 4-align the totalSize to 4-align the size of the serialized form
190 int32_t encodingStrPadding = totalSize & 3;
191 if (encodingStrPadding != 0) {
192 encodingStrPadding = 4 - encodingStrPadding;
193 }
194 newSelector->encodingStrLength = totalSize += encodingStrPadding;
195 char* allStrings = (char*) uprv_malloc(totalSize);
196 if (!allStrings) {
197 *status = U_MEMORY_ALLOCATION_ERROR;
198 return NULL;
199 }
201 for (i = 0; i < converterListSize; i++) {
202 newSelector->encodings[i] = allStrings;
203 uprv_strcpy(newSelector->encodings[i],
204 converterList != NULL ? converterList[i] : ucnv_getAvailableName(i));
205 allStrings += uprv_strlen(newSelector->encodings[i]) + 1;
206 }
207 while (encodingStrPadding > 0) {
208 *allStrings++ = 0;
209 --encodingStrPadding;
210 }
212 newSelector->ownEncodingStrings = TRUE;
213 newSelector->encodingsCount = converterListSize;
214 UPropsVectors *upvec = upvec_open((converterListSize+31)/32, status);
215 generateSelectorData(newSelector.getAlias(), upvec, excludedCodePoints, whichSet, status);
216 upvec_close(upvec);
218 if (U_FAILURE(*status)) {
219 return NULL;
220 }
222 return newSelector.orphan();
223 }
225 /* close opened selector */
226 U_CAPI void U_EXPORT2
227 ucnvsel_close(UConverterSelector *sel) {
228 if (!sel) {
229 return;
230 }
231 if (sel->ownEncodingStrings) {
232 uprv_free(sel->encodings[0]);
233 }
234 uprv_free(sel->encodings);
235 if (sel->ownPv) {
236 uprv_free(sel->pv);
237 }
238 utrie2_close(sel->trie);
239 uprv_free(sel->swapped);
240 uprv_free(sel);
241 }
243 static const UDataInfo dataInfo = {
244 sizeof(UDataInfo),
245 0,
247 U_IS_BIG_ENDIAN,
248 U_CHARSET_FAMILY,
249 U_SIZEOF_UCHAR,
250 0,
252 { 0x43, 0x53, 0x65, 0x6c }, /* dataFormat="CSel" */
253 { 1, 0, 0, 0 }, /* formatVersion */
254 { 0, 0, 0, 0 } /* dataVersion */
255 };
257 enum {
258 UCNVSEL_INDEX_TRIE_SIZE, // trie size in bytes
259 UCNVSEL_INDEX_PV_COUNT, // number of uint32_t in the bit vectors
260 UCNVSEL_INDEX_NAMES_COUNT, // number of encoding names
261 UCNVSEL_INDEX_NAMES_LENGTH, // number of encoding name bytes including padding
262 UCNVSEL_INDEX_SIZE = 15, // bytes following the DataHeader
263 UCNVSEL_INDEX_COUNT = 16
264 };
266 /*
267 * Serialized form of a UConverterSelector, formatVersion 1:
268 *
269 * The serialized form begins with a standard ICU DataHeader with a UDataInfo
270 * as the template above.
271 * This is followed by:
272 * int32_t indexes[UCNVSEL_INDEX_COUNT]; // see index entry constants above
273 * serialized UTrie2; // indexes[UCNVSEL_INDEX_TRIE_SIZE] bytes
274 * uint32_t pv[indexes[UCNVSEL_INDEX_PV_COUNT]]; // bit vectors
275 * char* encodingNames[indexes[UCNVSEL_INDEX_NAMES_LENGTH]]; // NUL-terminated strings + padding
276 */
278 /* serialize a selector */
279 U_CAPI int32_t U_EXPORT2
280 ucnvsel_serialize(const UConverterSelector* sel,
281 void* buffer, int32_t bufferCapacity, UErrorCode* status) {
282 // check if already failed
283 if (U_FAILURE(*status)) {
284 return 0;
285 }
286 // ensure args make sense!
287 uint8_t *p = (uint8_t *)buffer;
288 if (bufferCapacity < 0 ||
289 (bufferCapacity > 0 && (p == NULL || (U_POINTER_MASK_LSB(p, 3) != 0)))
290 ) {
291 *status = U_ILLEGAL_ARGUMENT_ERROR;
292 return 0;
293 }
294 // add up the size of the serialized form
295 int32_t serializedTrieSize = utrie2_serialize(sel->trie, NULL, 0, status);
296 if (*status != U_BUFFER_OVERFLOW_ERROR && U_FAILURE(*status)) {
297 return 0;
298 }
299 *status = U_ZERO_ERROR;
301 DataHeader header;
302 uprv_memset(&header, 0, sizeof(header));
303 header.dataHeader.headerSize = (uint16_t)((sizeof(header) + 15) & ~15);
304 header.dataHeader.magic1 = 0xda;
305 header.dataHeader.magic2 = 0x27;
306 uprv_memcpy(&header.info, &dataInfo, sizeof(dataInfo));
308 int32_t indexes[UCNVSEL_INDEX_COUNT] = {
309 serializedTrieSize,
310 sel->pvCount,
311 sel->encodingsCount,
312 sel->encodingStrLength
313 };
315 int32_t totalSize =
316 header.dataHeader.headerSize +
317 (int32_t)sizeof(indexes) +
318 serializedTrieSize +
319 sel->pvCount * 4 +
320 sel->encodingStrLength;
321 indexes[UCNVSEL_INDEX_SIZE] = totalSize - header.dataHeader.headerSize;
322 if (totalSize > bufferCapacity) {
323 *status = U_BUFFER_OVERFLOW_ERROR;
324 return totalSize;
325 }
326 // ok, save!
327 int32_t length = header.dataHeader.headerSize;
328 uprv_memcpy(p, &header, sizeof(header));
329 uprv_memset(p + sizeof(header), 0, length - sizeof(header));
330 p += length;
332 length = (int32_t)sizeof(indexes);
333 uprv_memcpy(p, indexes, length);
334 p += length;
336 utrie2_serialize(sel->trie, p, serializedTrieSize, status);
337 p += serializedTrieSize;
339 length = sel->pvCount * 4;
340 uprv_memcpy(p, sel->pv, length);
341 p += length;
343 uprv_memcpy(p, sel->encodings[0], sel->encodingStrLength);
344 p += sel->encodingStrLength;
346 return totalSize;
347 }
349 /**
350 * swap a selector into the desired Endianness and Asciiness of
351 * the system. Just as FYI, selectors are always saved in the format
352 * of the system that created them. They are only converted if used
353 * on another system. In other words, selectors created on different
354 * system can be different even if the params are identical (endianness
355 * and Asciiness differences only)
356 *
357 * @param ds pointer to data swapper containing swapping info
358 * @param inData pointer to incoming data
359 * @param length length of inData in bytes
360 * @param outData pointer to output data. Capacity should
361 * be at least equal to capacity of inData
362 * @param status an in/out ICU UErrorCode
363 * @return 0 on failure, number of bytes swapped on success
364 * number of bytes swapped can be smaller than length
365 */
366 static int32_t
367 ucnvsel_swap(const UDataSwapper *ds,
368 const void *inData, int32_t length,
369 void *outData, UErrorCode *status) {
370 /* udata_swapDataHeader checks the arguments */
371 int32_t headerSize = udata_swapDataHeader(ds, inData, length, outData, status);
372 if(U_FAILURE(*status)) {
373 return 0;
374 }
376 /* check data format and format version */
377 const UDataInfo *pInfo = (const UDataInfo *)((const char *)inData + 4);
378 if(!(
379 pInfo->dataFormat[0] == 0x43 && /* dataFormat="CSel" */
380 pInfo->dataFormat[1] == 0x53 &&
381 pInfo->dataFormat[2] == 0x65 &&
382 pInfo->dataFormat[3] == 0x6c
383 )) {
384 udata_printError(ds, "ucnvsel_swap(): data format %02x.%02x.%02x.%02x is not recognized as UConverterSelector data\n",
385 pInfo->dataFormat[0], pInfo->dataFormat[1],
386 pInfo->dataFormat[2], pInfo->dataFormat[3]);
387 *status = U_INVALID_FORMAT_ERROR;
388 return 0;
389 }
390 if(pInfo->formatVersion[0] != 1) {
391 udata_printError(ds, "ucnvsel_swap(): format version %02x is not supported\n",
392 pInfo->formatVersion[0]);
393 *status = U_UNSUPPORTED_ERROR;
394 return 0;
395 }
397 if(length >= 0) {
398 length -= headerSize;
399 if(length < 16*4) {
400 udata_printError(ds, "ucnvsel_swap(): too few bytes (%d after header) for UConverterSelector data\n",
401 length);
402 *status = U_INDEX_OUTOFBOUNDS_ERROR;
403 return 0;
404 }
405 }
407 const uint8_t *inBytes = (const uint8_t *)inData + headerSize;
408 uint8_t *outBytes = (uint8_t *)outData + headerSize;
410 /* read the indexes */
411 const int32_t *inIndexes = (const int32_t *)inBytes;
412 int32_t indexes[16];
413 int32_t i;
414 for(i = 0; i < 16; ++i) {
415 indexes[i] = udata_readInt32(ds, inIndexes[i]);
416 }
418 /* get the total length of the data */
419 int32_t size = indexes[UCNVSEL_INDEX_SIZE];
420 if(length >= 0) {
421 if(length < size) {
422 udata_printError(ds, "ucnvsel_swap(): too few bytes (%d after header) for all of UConverterSelector data\n",
423 length);
424 *status = U_INDEX_OUTOFBOUNDS_ERROR;
425 return 0;
426 }
428 /* copy the data for inaccessible bytes */
429 if(inBytes != outBytes) {
430 uprv_memcpy(outBytes, inBytes, size);
431 }
433 int32_t offset = 0, count;
435 /* swap the int32_t indexes[] */
436 count = UCNVSEL_INDEX_COUNT*4;
437 ds->swapArray32(ds, inBytes, count, outBytes, status);
438 offset += count;
440 /* swap the UTrie2 */
441 count = indexes[UCNVSEL_INDEX_TRIE_SIZE];
442 utrie2_swap(ds, inBytes + offset, count, outBytes + offset, status);
443 offset += count;
445 /* swap the uint32_t pv[] */
446 count = indexes[UCNVSEL_INDEX_PV_COUNT]*4;
447 ds->swapArray32(ds, inBytes + offset, count, outBytes + offset, status);
448 offset += count;
450 /* swap the encoding names */
451 count = indexes[UCNVSEL_INDEX_NAMES_LENGTH];
452 ds->swapInvChars(ds, inBytes + offset, count, outBytes + offset, status);
453 offset += count;
455 U_ASSERT(offset == size);
456 }
458 return headerSize + size;
459 }
461 /* unserialize a selector */
462 U_CAPI UConverterSelector* U_EXPORT2
463 ucnvsel_openFromSerialized(const void* buffer, int32_t length, UErrorCode* status) {
464 // check if already failed
465 if (U_FAILURE(*status)) {
466 return NULL;
467 }
468 // ensure args make sense!
469 const uint8_t *p = (const uint8_t *)buffer;
470 if (length <= 0 ||
471 (length > 0 && (p == NULL || (U_POINTER_MASK_LSB(p, 3) != 0)))
472 ) {
473 *status = U_ILLEGAL_ARGUMENT_ERROR;
474 return NULL;
475 }
476 // header
477 if (length < 32) {
478 // not even enough space for a minimal header
479 *status = U_INDEX_OUTOFBOUNDS_ERROR;
480 return NULL;
481 }
482 const DataHeader *pHeader = (const DataHeader *)p;
483 if (!(
484 pHeader->dataHeader.magic1==0xda &&
485 pHeader->dataHeader.magic2==0x27 &&
486 pHeader->info.dataFormat[0] == 0x43 &&
487 pHeader->info.dataFormat[1] == 0x53 &&
488 pHeader->info.dataFormat[2] == 0x65 &&
489 pHeader->info.dataFormat[3] == 0x6c
490 )) {
491 /* header not valid or dataFormat not recognized */
492 *status = U_INVALID_FORMAT_ERROR;
493 return NULL;
494 }
495 if (pHeader->info.formatVersion[0] != 1) {
496 *status = U_UNSUPPORTED_ERROR;
497 return NULL;
498 }
499 uint8_t* swapped = NULL;
500 if (pHeader->info.isBigEndian != U_IS_BIG_ENDIAN ||
501 pHeader->info.charsetFamily != U_CHARSET_FAMILY
502 ) {
503 // swap the data
504 UDataSwapper *ds =
505 udata_openSwapperForInputData(p, length, U_IS_BIG_ENDIAN, U_CHARSET_FAMILY, status);
506 int32_t totalSize = ucnvsel_swap(ds, p, -1, NULL, status);
507 if (U_FAILURE(*status)) {
508 udata_closeSwapper(ds);
509 return NULL;
510 }
511 if (length < totalSize) {
512 udata_closeSwapper(ds);
513 *status = U_INDEX_OUTOFBOUNDS_ERROR;
514 return NULL;
515 }
516 swapped = (uint8_t*)uprv_malloc(totalSize);
517 if (swapped == NULL) {
518 udata_closeSwapper(ds);
519 *status = U_MEMORY_ALLOCATION_ERROR;
520 return NULL;
521 }
522 ucnvsel_swap(ds, p, length, swapped, status);
523 udata_closeSwapper(ds);
524 if (U_FAILURE(*status)) {
525 uprv_free(swapped);
526 return NULL;
527 }
528 p = swapped;
529 pHeader = (const DataHeader *)p;
530 }
531 if (length < (pHeader->dataHeader.headerSize + 16 * 4)) {
532 // not even enough space for the header and the indexes
533 uprv_free(swapped);
534 *status = U_INDEX_OUTOFBOUNDS_ERROR;
535 return NULL;
536 }
537 p += pHeader->dataHeader.headerSize;
538 length -= pHeader->dataHeader.headerSize;
539 // indexes
540 const int32_t *indexes = (const int32_t *)p;
541 if (length < indexes[UCNVSEL_INDEX_SIZE]) {
542 uprv_free(swapped);
543 *status = U_INDEX_OUTOFBOUNDS_ERROR;
544 return NULL;
545 }
546 p += UCNVSEL_INDEX_COUNT * 4;
547 // create and populate the selector object
548 UConverterSelector* sel = (UConverterSelector*)uprv_malloc(sizeof(UConverterSelector));
549 char **encodings =
550 (char **)uprv_malloc(
551 indexes[UCNVSEL_INDEX_NAMES_COUNT] * sizeof(char *));
552 if (sel == NULL || encodings == NULL) {
553 uprv_free(swapped);
554 uprv_free(sel);
555 uprv_free(encodings);
556 *status = U_MEMORY_ALLOCATION_ERROR;
557 return NULL;
558 }
559 uprv_memset(sel, 0, sizeof(UConverterSelector));
560 sel->pvCount = indexes[UCNVSEL_INDEX_PV_COUNT];
561 sel->encodings = encodings;
562 sel->encodingsCount = indexes[UCNVSEL_INDEX_NAMES_COUNT];
563 sel->encodingStrLength = indexes[UCNVSEL_INDEX_NAMES_LENGTH];
564 sel->swapped = swapped;
565 // trie
566 sel->trie = utrie2_openFromSerialized(UTRIE2_16_VALUE_BITS,
567 p, indexes[UCNVSEL_INDEX_TRIE_SIZE], NULL,
568 status);
569 p += indexes[UCNVSEL_INDEX_TRIE_SIZE];
570 if (U_FAILURE(*status)) {
571 ucnvsel_close(sel);
572 return NULL;
573 }
574 // bit vectors
575 sel->pv = (uint32_t *)p;
576 p += sel->pvCount * 4;
577 // encoding names
578 char* s = (char*)p;
579 for (int32_t i = 0; i < sel->encodingsCount; ++i) {
580 sel->encodings[i] = s;
581 s += uprv_strlen(s) + 1;
582 }
583 p += sel->encodingStrLength;
585 return sel;
586 }
588 // a bunch of functions for the enumeration thingie! Nothing fancy here. Just
589 // iterate over the selected encodings
590 struct Enumerator {
591 int16_t* index;
592 int16_t length;
593 int16_t cur;
594 const UConverterSelector* sel;
595 };
597 U_CDECL_BEGIN
599 static void U_CALLCONV
600 ucnvsel_close_selector_iterator(UEnumeration *enumerator) {
601 uprv_free(((Enumerator*)(enumerator->context))->index);
602 uprv_free(enumerator->context);
603 uprv_free(enumerator);
604 }
607 static int32_t U_CALLCONV
608 ucnvsel_count_encodings(UEnumeration *enumerator, UErrorCode *status) {
609 // check if already failed
610 if (U_FAILURE(*status)) {
611 return 0;
612 }
613 return ((Enumerator*)(enumerator->context))->length;
614 }
617 static const char* U_CALLCONV ucnvsel_next_encoding(UEnumeration* enumerator,
618 int32_t* resultLength,
619 UErrorCode* status) {
620 // check if already failed
621 if (U_FAILURE(*status)) {
622 return NULL;
623 }
625 int16_t cur = ((Enumerator*)(enumerator->context))->cur;
626 const UConverterSelector* sel;
627 const char* result;
628 if (cur >= ((Enumerator*)(enumerator->context))->length) {
629 return NULL;
630 }
631 sel = ((Enumerator*)(enumerator->context))->sel;
632 result = sel->encodings[((Enumerator*)(enumerator->context))->index[cur] ];
633 ((Enumerator*)(enumerator->context))->cur++;
634 if (resultLength) {
635 *resultLength = (int32_t)uprv_strlen(result);
636 }
637 return result;
638 }
640 static void U_CALLCONV ucnvsel_reset_iterator(UEnumeration* enumerator,
641 UErrorCode* status) {
642 // check if already failed
643 if (U_FAILURE(*status)) {
644 return ;
645 }
646 ((Enumerator*)(enumerator->context))->cur = 0;
647 }
649 U_CDECL_END
652 static const UEnumeration defaultEncodings = {
653 NULL,
654 NULL,
655 ucnvsel_close_selector_iterator,
656 ucnvsel_count_encodings,
657 uenum_unextDefault,
658 ucnvsel_next_encoding,
659 ucnvsel_reset_iterator
660 };
663 // internal fn to intersect two sets of masks
664 // returns whether the mask has reduced to all zeros
665 static UBool intersectMasks(uint32_t* dest, const uint32_t* source1, int32_t len) {
666 int32_t i;
667 uint32_t oredDest = 0;
668 for (i = 0 ; i < len ; ++i) {
669 oredDest |= (dest[i] &= source1[i]);
670 }
671 return oredDest == 0;
672 }
674 // internal fn to count how many 1's are there in a mask
675 // algorithm taken from http://graphics.stanford.edu/~seander/bithacks.html
676 static int16_t countOnes(uint32_t* mask, int32_t len) {
677 int32_t i, totalOnes = 0;
678 for (i = 0 ; i < len ; ++i) {
679 uint32_t ent = mask[i];
680 for (; ent; totalOnes++)
681 {
682 ent &= ent - 1; // clear the least significant bit set
683 }
684 }
685 return totalOnes;
686 }
689 /* internal function! */
690 static UEnumeration *selectForMask(const UConverterSelector* sel,
691 uint32_t *mask, UErrorCode *status) {
692 // this is the context we will use. Store a table of indices to which
693 // encodings are legit.
694 struct Enumerator* result = (Enumerator*)uprv_malloc(sizeof(Enumerator));
695 if (result == NULL) {
696 uprv_free(mask);
697 *status = U_MEMORY_ALLOCATION_ERROR;
698 return NULL;
699 }
700 result->index = NULL; // this will be allocated later!
701 result->length = result->cur = 0;
702 result->sel = sel;
704 UEnumeration *en = (UEnumeration *)uprv_malloc(sizeof(UEnumeration));
705 if (en == NULL) {
706 // TODO(markus): Combine Enumerator and UEnumeration into one struct.
707 uprv_free(mask);
708 uprv_free(result);
709 *status = U_MEMORY_ALLOCATION_ERROR;
710 return NULL;
711 }
712 memcpy(en, &defaultEncodings, sizeof(UEnumeration));
713 en->context = result;
715 int32_t columns = (sel->encodingsCount+31)/32;
716 int16_t numOnes = countOnes(mask, columns);
717 // now, we know the exact space we need for index
718 if (numOnes > 0) {
719 result->index = (int16_t*) uprv_malloc(numOnes * sizeof(int16_t));
721 int32_t i, j;
722 int16_t k = 0;
723 for (j = 0 ; j < columns; j++) {
724 uint32_t v = mask[j];
725 for (i = 0 ; i < 32 && k < sel->encodingsCount; i++, k++) {
726 if ((v & 1) != 0) {
727 result->index[result->length++] = k;
728 }
729 v >>= 1;
730 }
731 }
732 } //otherwise, index will remain NULL (and will never be touched by
733 //the enumerator code anyway)
734 uprv_free(mask);
735 return en;
736 }
738 /* check a string against the selector - UTF16 version */
739 U_CAPI UEnumeration * U_EXPORT2
740 ucnvsel_selectForString(const UConverterSelector* sel,
741 const UChar *s, int32_t length, UErrorCode *status) {
742 // check if already failed
743 if (U_FAILURE(*status)) {
744 return NULL;
745 }
746 // ensure args make sense!
747 if (sel == NULL || (s == NULL && length != 0)) {
748 *status = U_ILLEGAL_ARGUMENT_ERROR;
749 return NULL;
750 }
752 int32_t columns = (sel->encodingsCount+31)/32;
753 uint32_t* mask = (uint32_t*) uprv_malloc(columns * 4);
754 if (mask == NULL) {
755 *status = U_MEMORY_ALLOCATION_ERROR;
756 return NULL;
757 }
758 uprv_memset(mask, ~0, columns *4);
760 if(s!=NULL) {
761 const UChar *limit;
762 if (length >= 0) {
763 limit = s + length;
764 } else {
765 limit = NULL;
766 }
768 while (limit == NULL ? *s != 0 : s != limit) {
769 UChar32 c;
770 uint16_t pvIndex;
771 UTRIE2_U16_NEXT16(sel->trie, s, limit, c, pvIndex);
772 if (intersectMasks(mask, sel->pv+pvIndex, columns)) {
773 break;
774 }
775 }
776 }
777 return selectForMask(sel, mask, status);
778 }
780 /* check a string against the selector - UTF8 version */
781 U_CAPI UEnumeration * U_EXPORT2
782 ucnvsel_selectForUTF8(const UConverterSelector* sel,
783 const char *s, int32_t length, UErrorCode *status) {
784 // check if already failed
785 if (U_FAILURE(*status)) {
786 return NULL;
787 }
788 // ensure args make sense!
789 if (sel == NULL || (s == NULL && length != 0)) {
790 *status = U_ILLEGAL_ARGUMENT_ERROR;
791 return NULL;
792 }
794 int32_t columns = (sel->encodingsCount+31)/32;
795 uint32_t* mask = (uint32_t*) uprv_malloc(columns * 4);
796 if (mask == NULL) {
797 *status = U_MEMORY_ALLOCATION_ERROR;
798 return NULL;
799 }
800 uprv_memset(mask, ~0, columns *4);
802 if (length < 0) {
803 length = (int32_t)uprv_strlen(s);
804 }
806 if(s!=NULL) {
807 const char *limit = s + length;
809 while (s != limit) {
810 uint16_t pvIndex;
811 UTRIE2_U8_NEXT16(sel->trie, s, limit, pvIndex);
812 if (intersectMasks(mask, sel->pv+pvIndex, columns)) {
813 break;
814 }
815 }
816 }
817 return selectForMask(sel, mask, status);
818 }
820 #endif // !UCONFIG_NO_CONVERSION
