| /* |
| ********************************************************************** |
| * Copyright (C) 1999-2001, International Business Machines |
| * Corporation and others. All Rights Reserved. |
| ********************************************************************** |
| * Date Name Description |
| * 11/17/99 aliu Creation. |
| ********************************************************************** |
| */ |
| |
| #include "unicode/utypes.h" |
| |
| #if !UCONFIG_NO_TRANSLITERATION |
| |
| #include "unicode/rep.h" |
| #include "unicode/unifilt.h" |
| #include "unicode/uniset.h" |
| #include "rbt_rule.h" |
| #include "rbt_data.h" |
| #include "cmemory.h" |
| #include "strmatch.h" |
| #include "strrepl.h" |
| #include "util.h" |
| |
| static const UChar FORWARD_OP[] = {32,62,32,0}; // " > " |
| |
| U_NAMESPACE_BEGIN |
| |
| /** |
| * Construct a new rule with the given input, output text, and other |
| * attributes. A cursor position may be specified for the output text. |
| * @param input input string, including key and optional ante and |
| * post context |
| * @param anteContextPos offset into input to end of ante context, or -1 if |
| * none. Must be <= input.length() if not -1. |
| * @param postContextPos offset into input to start of post context, or -1 |
| * if none. Must be <= input.length() if not -1, and must be >= |
| * anteContextPos. |
| * @param output output string |
| * @param cursorPosition offset into output at which cursor is located, or -1 if |
| * none. If less than zero, then the cursor is placed after the |
| * <code>output</code>; that is, -1 is equivalent to |
| * <code>output.length()</code>. If greater than |
| * <code>output.length()</code> then an exception is thrown. |
| * @param segs array of UnicodeFunctors corresponding to input pattern |
| * segments, or null if there are none. The array itself is adopted, |
| * but the pointers within it are not. |
| * @param segsCount number of elements in segs[] |
| * @param anchorStart TRUE if the the rule is anchored on the left to |
| * the context start |
| * @param anchorEnd TRUE if the rule is anchored on the right to the |
| * context limit |
| */ |
| TransliterationRule::TransliterationRule(const UnicodeString& input, |
| int32_t anteContextPos, int32_t postContextPos, |
| const UnicodeString& outputStr, |
| int32_t cursorPosition, int32_t cursorOffset, |
| UnicodeFunctor** segs, |
| int32_t segsCount, |
| UBool anchorStart, UBool anchorEnd, |
| const TransliterationRuleData* theData, |
| UErrorCode& status) : |
| UMemory(), |
| segments(0), |
| data(theData) { |
| |
| if (U_FAILURE(status)) { |
| return; |
| } |
| // Do range checks only when warranted to save time |
| if (anteContextPos < 0) { |
| anteContextLength = 0; |
| } else { |
| if (anteContextPos > input.length()) { |
| // throw new IllegalArgumentException("Invalid ante context"); |
| status = U_ILLEGAL_ARGUMENT_ERROR; |
| return; |
| } |
| anteContextLength = anteContextPos; |
| } |
| if (postContextPos < 0) { |
| keyLength = input.length() - anteContextLength; |
| } else { |
| if (postContextPos < anteContextLength || |
| postContextPos > input.length()) { |
| // throw new IllegalArgumentException("Invalid post context"); |
| status = U_ILLEGAL_ARGUMENT_ERROR; |
| return; |
| } |
| keyLength = postContextPos - anteContextLength; |
| } |
| if (cursorPosition < 0) { |
| cursorPosition = outputStr.length(); |
| } else if (cursorPosition > outputStr.length()) { |
| // throw new IllegalArgumentException("Invalid cursor position"); |
| status = U_ILLEGAL_ARGUMENT_ERROR; |
| return; |
| } |
| // We don't validate the segments array. The caller must |
| // guarantee that the segments are well-formed (that is, that |
| // all $n references in the output refer to indices of this |
| // array, and that no array elements are null). |
| this->segments = segs; |
| this->segmentsCount = segsCount; |
| |
| pattern = input; |
| flags = 0; |
| if (anchorStart) { |
| flags |= ANCHOR_START; |
| } |
| if (anchorEnd) { |
| flags |= ANCHOR_END; |
| } |
| |
| anteContext = NULL; |
| if (anteContextLength > 0) { |
| anteContext = new StringMatcher(pattern, 0, anteContextLength, |
| FALSE, *data); |
| /* test for NULL */ |
| if (anteContext == 0) { |
| status = U_MEMORY_ALLOCATION_ERROR; |
| return; |
| } |
| } |
| |
| key = NULL; |
| if (keyLength > 0) { |
| key = new StringMatcher(pattern, anteContextLength, anteContextLength + keyLength, |
| FALSE, *data); |
| /* test for NULL */ |
| if (key == 0) { |
| status = U_MEMORY_ALLOCATION_ERROR; |
| return; |
| } |
| } |
| |
| int32_t postContextLength = pattern.length() - keyLength - anteContextLength; |
| postContext = NULL; |
| if (postContextLength > 0) { |
| postContext = new StringMatcher(pattern, anteContextLength + keyLength, pattern.length(), |
| FALSE, *data); |
| /* test for NULL */ |
| if (postContext == 0) { |
| status = U_MEMORY_ALLOCATION_ERROR; |
| return; |
| } |
| } |
| |
| this->output = new StringReplacer(outputStr, cursorPosition + cursorOffset, data); |
| /* test for NULL */ |
| if (this->output == 0) { |
| status = U_MEMORY_ALLOCATION_ERROR; |
| return; |
| } |
| } |
| |
| /** |
| * Copy constructor. |
| */ |
| TransliterationRule::TransliterationRule(TransliterationRule& other) : |
| UMemory(other), |
| anteContext(NULL), |
| key(NULL), |
| postContext(NULL), |
| pattern(other.pattern), |
| anteContextLength(other.anteContextLength), |
| keyLength(other.keyLength), |
| flags(other.flags), |
| data(other.data) { |
| |
| segments = NULL; |
| segmentsCount = 0; |
| if (other.segmentsCount > 0) { |
| segments = (UnicodeFunctor **)uprv_malloc(other.segmentsCount * sizeof(UnicodeFunctor *)); |
| uprv_memcpy(segments, other.segments, other.segmentsCount*sizeof(segments[0])); |
| } |
| |
| if (other.anteContext != NULL) { |
| anteContext = (StringMatcher*) other.anteContext->clone(); |
| } |
| if (other.key != NULL) { |
| key = (StringMatcher*) other.key->clone(); |
| } |
| if (other.postContext != NULL) { |
| postContext = (StringMatcher*) other.postContext->clone(); |
| } |
| output = other.output->clone(); |
| } |
| |
| TransliterationRule::~TransliterationRule() { |
| uprv_free(segments); |
| delete anteContext; |
| delete key; |
| delete postContext; |
| delete output; |
| } |
| |
| /** |
| * Return the preceding context length. This method is needed to |
| * support the <code>Transliterator</code> method |
| * <code>getMaximumContextLength()</code>. Internally, this is |
| * implemented as the anteContextLength, optionally plus one if |
| * there is a start anchor. The one character anchor gap is |
| * needed to make repeated incremental transliteration with |
| * anchors work. |
| */ |
| int32_t TransliterationRule::getContextLength(void) const { |
| return anteContextLength + ((flags & ANCHOR_START) ? 1 : 0); |
| } |
| |
| /** |
| * Internal method. Returns 8-bit index value for this rule. |
| * This is the low byte of the first character of the key, |
| * unless the first character of the key is a set. If it's a |
| * set, or otherwise can match multiple keys, the index value is -1. |
| */ |
| int16_t TransliterationRule::getIndexValue() const { |
| if (anteContextLength == pattern.length()) { |
| // A pattern with just ante context {such as foo)>bar} can |
| // match any key. |
| return -1; |
| } |
| UChar32 c = pattern.char32At(anteContextLength); |
| return (int16_t)(data->lookupMatcher(c) == NULL ? (c & 0xFF) : -1); |
| } |
| |
| /** |
| * Internal method. Returns true if this rule matches the given |
| * index value. The index value is an 8-bit integer, 0..255, |
| * representing the low byte of the first character of the key. |
| * It matches this rule if it matches the first character of the |
| * key, or if the first character of the key is a set, and the set |
| * contains any character with a low byte equal to the index |
| * value. If the rule contains only ante context, as in foo)>bar, |
| * then it will match any key. |
| */ |
| UBool TransliterationRule::matchesIndexValue(uint8_t v) const { |
| // Delegate to the key, or if there is none, to the postContext. |
| // If there is neither then we match any key; return true. |
| UnicodeMatcher *m = (key != NULL) ? key : postContext; |
| return (m != NULL) ? m->matchesIndexValue(v) : TRUE; |
| } |
| |
| /** |
| * Return true if this rule masks another rule. If r1 masks r2 then |
| * r1 matches any input string that r2 matches. If r1 masks r2 and r2 masks |
| * r1 then r1 == r2. Examples: "a>x" masks "ab>y". "a>x" masks "a[b]>y". |
| * "[c]a>x" masks "[dc]a>y". |
| */ |
| UBool TransliterationRule::masks(const TransliterationRule& r2) const { |
| /* Rule r1 masks rule r2 if the string formed of the |
| * antecontext, key, and postcontext overlaps in the following |
| * way: |
| * |
| * r1: aakkkpppp |
| * r2: aaakkkkkpppp |
| * ^ |
| * |
| * The strings must be aligned at the first character of the |
| * key. The length of r1 to the left of the alignment point |
| * must be <= the length of r2 to the left; ditto for the |
| * right. The characters of r1 must equal (or be a superset |
| * of) the corresponding characters of r2. The superset |
| * operation should be performed to check for UnicodeSet |
| * masking. |
| * |
| * Anchors: Two patterns that differ only in anchors only |
| * mask one another if they are exactly equal, and r2 has |
| * all the anchors r1 has (optionally, plus some). Here Y |
| * means the row masks the column, N means it doesn't. |
| * |
| * ab ^ab ab$ ^ab$ |
| * ab Y Y Y Y |
| * ^ab N Y N Y |
| * ab$ N N Y Y |
| * ^ab$ N N N Y |
| * |
| * Post context: {a}b masks ab, but not vice versa, since {a}b |
| * matches everything ab matches, and {a}b matches {|a|}b but ab |
| * does not. Pre context is different (a{b} does not align with |
| * ab). |
| */ |
| |
| /* LIMITATION of the current mask algorithm: Some rule |
| * maskings are currently not detected. For example, |
| * "{Lu}]a>x" masks "A]a>y". This can be added later. TODO |
| */ |
| |
| int32_t len = pattern.length(); |
| int32_t left = anteContextLength; |
| int32_t left2 = r2.anteContextLength; |
| int32_t right = len - left; |
| int32_t right2 = r2.pattern.length() - left2; |
| |
| // TODO Clean this up -- some logic might be combinable with the |
| // next statement. |
| |
| // Test for anchor masking |
| if (left == left2 && right == right2 && |
| keyLength <= r2.keyLength && |
| 0 == r2.pattern.compare(0, len, pattern)) { |
| // The following boolean logic implements the table above |
| return (flags == r2.flags) || |
| (!(flags & ANCHOR_START) && !(flags & ANCHOR_END)) || |
| ((r2.flags & ANCHOR_START) && (r2.flags & ANCHOR_END)); |
| } |
| |
| return left <= left2 && |
| (right < right2 || |
| (right == right2 && keyLength <= r2.keyLength)) && |
| 0 == r2.pattern.compare(left2 - left, len, pattern); |
| } |
| |
| static inline int32_t posBefore(const Replaceable& str, int32_t pos) { |
| return (pos > 0) ? |
| pos - UTF_CHAR_LENGTH(str.char32At(pos-1)) : |
| pos - 1; |
| } |
| |
| static inline int32_t posAfter(const Replaceable& str, int32_t pos) { |
| return (pos >= 0 && pos < str.length()) ? |
| pos + UTF_CHAR_LENGTH(str.char32At(pos)) : |
| pos + 1; |
| } |
| |
| /** |
| * Attempt a match and replacement at the given position. Return |
| * the degree of match between this rule and the given text. The |
| * degree of match may be mismatch, a partial match, or a full |
| * match. A mismatch means at least one character of the text |
| * does not match the context or key. A partial match means some |
| * context and key characters match, but the text is not long |
| * enough to match all of them. A full match means all context |
| * and key characters match. |
| * |
| * If a full match is obtained, perform a replacement, update pos, |
| * and return U_MATCH. Otherwise both text and pos are unchanged. |
| * |
| * @param text the text |
| * @param pos the position indices |
| * @param incremental if TRUE, test for partial matches that may |
| * be completed by additional text inserted at pos.limit. |
| * @return one of <code>U_MISMATCH</code>, |
| * <code>U_PARTIAL_MATCH</code>, or <code>U_MATCH</code>. If |
| * incremental is FALSE then U_PARTIAL_MATCH will not be returned. |
| */ |
| UMatchDegree TransliterationRule::matchAndReplace(Replaceable& text, |
| UTransPosition& pos, |
| UBool incremental) const { |
| // Matching and replacing are done in one method because the |
| // replacement operation needs information obtained during the |
| // match. Another way to do this is to have the match method |
| // create a match result struct with relevant offsets, and to pass |
| // this into the replace method. |
| |
| // ============================ MATCH =========================== |
| |
| // Reset segment match data |
| if (segments != NULL) { |
| for (int32_t i=0; i<segmentsCount; ++i) { |
| ((StringMatcher*) segments[i])->resetMatch(); |
| } |
| } |
| |
| // int32_t lenDelta, keyLimit; |
| int32_t keyLimit; |
| |
| // ------------------------ Ante Context ------------------------ |
| |
| // A mismatch in the ante context, or with the start anchor, |
| // is an outright U_MISMATCH regardless of whether we are |
| // incremental or not. |
| int32_t oText; // offset into 'text' |
| // int32_t newStart = 0; |
| int32_t minOText; |
| |
| // Note (1): We process text in 16-bit code units, rather than |
| // 32-bit code points. This works because stand-ins are |
| // always in the BMP and because we are doing a literal match |
| // operation, which can be done 16-bits at a time. |
| |
| int32_t anteLimit = posBefore(text, pos.contextStart); |
| |
| UMatchDegree match; |
| |
| // Start reverse match at char before pos.start |
| oText = posBefore(text, pos.start); |
| |
| if (anteContext != NULL) { |
| match = anteContext->matches(text, oText, anteLimit, FALSE); |
| if (match != U_MATCH) { |
| return U_MISMATCH; |
| } |
| } |
| |
| minOText = posAfter(text, oText); |
| |
| // ------------------------ Start Anchor ------------------------ |
| |
| if (((flags & ANCHOR_START) != 0) && oText != anteLimit) { |
| return U_MISMATCH; |
| } |
| |
| // -------------------- Key and Post Context -------------------- |
| |
| oText = pos.start; |
| |
| if (key != NULL) { |
| match = key->matches(text, oText, pos.limit, incremental); |
| if (match != U_MATCH) { |
| return match; |
| } |
| } |
| |
| keyLimit = oText; |
| |
| if (postContext != NULL) { |
| if (incremental && keyLimit == pos.limit) { |
| // The key matches just before pos.limit, and there is |
| // a postContext. Since we are in incremental mode, |
| // we must assume more characters may be inserted at |
| // pos.limit -- this is a partial match. |
| return U_PARTIAL_MATCH; |
| } |
| |
| match = postContext->matches(text, oText, pos.contextLimit, incremental); |
| if (match != U_MATCH) { |
| return match; |
| } |
| } |
| |
| // ------------------------- Stop Anchor ------------------------ |
| |
| if (((flags & ANCHOR_END)) != 0) { |
| if (oText != pos.contextLimit) { |
| return U_MISMATCH; |
| } |
| if (incremental) { |
| return U_PARTIAL_MATCH; |
| } |
| } |
| |
| // =========================== REPLACE ========================== |
| |
| // We have a full match. The key is between pos.start and |
| // keyLimit. |
| |
| int32_t newStart; |
| int32_t newLength = output->toReplacer()->replace(text, pos.start, keyLimit, newStart); |
| int32_t lenDelta = newLength - (keyLimit - pos.start); |
| |
| oText += lenDelta; |
| pos.limit += lenDelta; |
| pos.contextLimit += lenDelta; |
| // Restrict new value of start to [minOText, min(oText, pos.limit)]. |
| pos.start = uprv_max(minOText, uprv_min(uprv_min(oText, pos.limit), newStart)); |
| return U_MATCH; |
| } |
| |
| /** |
| * Create a source string that represents this rule. Append it to the |
| * given string. |
| */ |
| UnicodeString& TransliterationRule::toRule(UnicodeString& rule, |
| UBool escapeUnprintable) const { |
| |
| // Accumulate special characters (and non-specials following them) |
| // into quoteBuf. Append quoteBuf, within single quotes, when |
| // a non-quoted element must be inserted. |
| UnicodeString str, quoteBuf; |
| |
| // Do not emit the braces '{' '}' around the pattern if there |
| // is neither anteContext nor postContext. |
| UBool emitBraces = |
| (anteContext != NULL) || (postContext != NULL); |
| |
| // Emit start anchor |
| if ((flags & ANCHOR_START) != 0) { |
| rule.append((UChar)94/*^*/); |
| } |
| |
| // Emit the input pattern |
| ICU_Utility::appendToRule(rule, anteContext, escapeUnprintable, quoteBuf); |
| |
| if (emitBraces) { |
| ICU_Utility::appendToRule(rule, (UChar) 0x007B /*{*/, TRUE, escapeUnprintable, quoteBuf); |
| } |
| |
| ICU_Utility::appendToRule(rule, key, escapeUnprintable, quoteBuf); |
| |
| if (emitBraces) { |
| ICU_Utility::appendToRule(rule, (UChar) 0x007D /*}*/, TRUE, escapeUnprintable, quoteBuf); |
| } |
| |
| ICU_Utility::appendToRule(rule, postContext, escapeUnprintable, quoteBuf); |
| |
| // Emit end anchor |
| if ((flags & ANCHOR_END) != 0) { |
| rule.append((UChar)36/*$*/); |
| } |
| |
| ICU_Utility::appendToRule(rule, FORWARD_OP, TRUE, escapeUnprintable, quoteBuf); |
| |
| // Emit the output pattern |
| |
| ICU_Utility::appendToRule(rule, output->toReplacer()->toReplacerPattern(str, escapeUnprintable), |
| TRUE, escapeUnprintable, quoteBuf); |
| |
| ICU_Utility::appendToRule(rule, (UChar) 0x003B /*;*/, TRUE, escapeUnprintable, quoteBuf); |
| |
| return rule; |
| } |
| |
| void TransliterationRule::setData(const TransliterationRuleData* d) { |
| data = d; |
| if (anteContext != NULL) anteContext->setData(d); |
| if (postContext != NULL) postContext->setData(d); |
| if (key != NULL) key->setData(d); |
| // assert(output != NULL); |
| output->setData(d); |
| // Don't have to do segments since they are in the context or key |
| } |
| |
| /** |
| * Union the set of all characters that may be modified by this rule |
| * into the given set. |
| */ |
| void TransliterationRule::addSourceSetTo(UnicodeSet& toUnionTo) const { |
| int32_t limit = anteContextLength + keyLength; |
| for (int32_t i=anteContextLength; i<limit; ) { |
| UChar32 ch = pattern.char32At(i); |
| i += UTF_CHAR_LENGTH(ch); |
| const UnicodeMatcher* matcher = data->lookupMatcher(ch); |
| if (matcher == NULL) { |
| toUnionTo.add(ch); |
| } else { |
| matcher->addMatchSetTo(toUnionTo); |
| } |
| } |
| } |
| |
| /** |
| * Union the set of all characters that may be emitted by this rule |
| * into the given set. |
| */ |
| void TransliterationRule::addTargetSetTo(UnicodeSet& toUnionTo) const { |
| output->toReplacer()->addReplacementSetTo(toUnionTo); |
| } |
| |
| U_NAMESPACE_END |
| |
| #endif /* #if !UCONFIG_NO_TRANSLITERATION */ |
| |
| //eof |
