Check in the pristine copy of ICU 4.6...

icu46/source/i18n/strmatch.cpp

+/*
+**********************************************************************
+*   Copyright (c) 2001-2004, International Business Machines Corporation
+*   and others.  All Rights Reserved.
+**********************************************************************
+*   Date        Name        Description
+*   07/23/01    aliu        Creation.
+**********************************************************************
+*/
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_TRANSLITERATION
+
+#include "strmatch.h"
+#include "rbt_data.h"
+#include "util.h"
+#include "unicode/uniset.h"
+
+U_NAMESPACE_BEGIN
+
+static const UChar EMPTY[] = { 0 }; // empty string: ""
+
+UOBJECT_DEFINE_RTTI_IMPLEMENTATION(StringMatcher)
+
+StringMatcher::StringMatcher(const UnicodeString& theString,
+                             int32_t start,
+                             int32_t limit,
+                             int32_t segmentNum,
+                             const TransliterationRuleData& theData) :
+    data(&theData),
+    segmentNumber(segmentNum),
+    matchStart(-1),
+    matchLimit(-1)
+{
+    theString.extractBetween(start, limit, pattern);
+}
+
+StringMatcher::StringMatcher(const StringMatcher& o) :
+    UnicodeFunctor(o),
+    UnicodeMatcher(o),
+    UnicodeReplacer(o),
+    pattern(o.pattern),
+    data(o.data),
+    segmentNumber(o.segmentNumber),
+    matchStart(o.matchStart),
+    matchLimit(o.matchLimit)
+{
+}
+
+/**
+ * Destructor
+ */
+StringMatcher::~StringMatcher() {
+}
+
+/**
+ * Implement UnicodeFunctor
+ */
+UnicodeFunctor* StringMatcher::clone() const {
+    return new StringMatcher(*this);
+}
+
+/**
+ * UnicodeFunctor API.  Cast 'this' to a UnicodeMatcher* pointer
+ * and return the pointer.
+ */
+UnicodeMatcher* StringMatcher::toMatcher() const {
+    return (UnicodeMatcher*) this;
+}
+
+/**
+ * UnicodeFunctor API.  Cast 'this' to a UnicodeReplacer* pointer
+ * and return the pointer.
+ */
+UnicodeReplacer* StringMatcher::toReplacer() const {
+    return (UnicodeReplacer*) this;
+}
+
+/**
+ * Implement UnicodeMatcher
+ */
+UMatchDegree StringMatcher::matches(const Replaceable& text,
+                                    int32_t& offset,
+                                    int32_t limit,
+                                    UBool incremental) {
+    int32_t i;
+    int32_t cursor = offset;
+    if (limit < cursor) {
+        // Match in the reverse direction
+        for (i=pattern.length()-1; i>=0; --i) {
+            UChar keyChar = pattern.charAt(i);
+            UnicodeMatcher* subm = data->lookupMatcher(keyChar);
+            if (subm == 0) {
+                if (cursor > limit &&
+                    keyChar == text.charAt(cursor)) {
+                    --cursor;
+                } else {
+                    return U_MISMATCH;
+                }
+            } else {
+                UMatchDegree m =
+                    subm->matches(text, cursor, limit, incremental);
+                if (m != U_MATCH) {
+                    return m;
+                }
+            }
+        }
+        // Record the match position, but adjust for a normal
+        // forward start, limit, and only if a prior match does not
+        // exist -- we want the rightmost match.
+        if (matchStart < 0) {
+            matchStart = cursor+1;
+            matchLimit = offset+1;
+        }
+    } else {
+        for (i=0; i<pattern.length(); ++i) {
+            if (incremental && cursor == limit) {
+                // We've reached the context limit without a mismatch and
+                // without completing our match.
+                return U_PARTIAL_MATCH;
+            }
+            UChar keyChar = pattern.charAt(i);
+            UnicodeMatcher* subm = data->lookupMatcher(keyChar);
+            if (subm == 0) {
+                // Don't need the cursor < limit check if
+                // incremental is TRUE (because it's done above); do need
+                // it otherwise.
+                if (cursor < limit &&
+                    keyChar == text.charAt(cursor)) {
+                    ++cursor;
+                } else {
+                    return U_MISMATCH;
+                }
+            } else {
+                UMatchDegree m =
+                    subm->matches(text, cursor, limit, incremental);
+                if (m != U_MATCH) {
+                    return m;
+                }
+            }
+        }
+        // Record the match position
+        matchStart = offset;
+        matchLimit = cursor;
+    }
+
+    offset = cursor;
+    return U_MATCH;
+}
+
+/**
+ * Implement UnicodeMatcher
+ */
+UnicodeString& StringMatcher::toPattern(UnicodeString& result,
+                                        UBool escapeUnprintable) const
+{
+    result.truncate(0);
+    UnicodeString str, quoteBuf;
+    if (segmentNumber > 0) {
+        result.append((UChar)40); /*(*/
+    }
+    for (int32_t i=0; i<pattern.length(); ++i) {
+        UChar keyChar = pattern.charAt(i);
+        const UnicodeMatcher* m = data->lookupMatcher(keyChar);
+        if (m == 0) {
+            ICU_Utility::appendToRule(result, keyChar, FALSE, escapeUnprintable, quoteBuf);
+        } else {
+            ICU_Utility::appendToRule(result, m->toPattern(str, escapeUnprintable),
+                         TRUE, escapeUnprintable, quoteBuf);
+        }
+    }
+    if (segmentNumber > 0) {
+        result.append((UChar)41); /*)*/
+    }
+    // Flush quoteBuf out to result
+    ICU_Utility::appendToRule(result, -1,
+                              TRUE, escapeUnprintable, quoteBuf);
+    return result;
+}
+
+/**
+ * Implement UnicodeMatcher
+ */
+UBool StringMatcher::matchesIndexValue(uint8_t v) const {
+    if (pattern.length() == 0) {
+        return TRUE;
+    }
+    UChar32 c = pattern.char32At(0);
+    const UnicodeMatcher *m = data->lookupMatcher(c);
+    return (m == 0) ? ((c & 0xFF) == v) : m->matchesIndexValue(v);
+}
+
+/**
+ * Implement UnicodeMatcher
+ */
+void StringMatcher::addMatchSetTo(UnicodeSet& toUnionTo) const {
+    UChar32 ch;
+    for (int32_t i=0; i<pattern.length(); i+=UTF_CHAR_LENGTH(ch)) {
+        ch = pattern.char32At(i);
+        const UnicodeMatcher* matcher = data->lookupMatcher(ch);
+        if (matcher == NULL) {
+            toUnionTo.add(ch);
+        } else {
+            matcher->addMatchSetTo(toUnionTo);
+        }
+    }
+}
+
+/**
+ * UnicodeReplacer API
+ */
+int32_t StringMatcher::replace(Replaceable& text,
+                               int32_t start,
+                               int32_t limit,
+                               int32_t& /*cursor*/) {
+    
+    int32_t outLen = 0;
+    
+    // Copy segment with out-of-band data
+    int32_t dest = limit;
+    // If there was no match, that means that a quantifier
+    // matched zero-length.  E.g., x (a)* y matched "xy".
+    if (matchStart >= 0) {
+        if (matchStart != matchLimit) {
+            text.copy(matchStart, matchLimit, dest);
+            outLen = matchLimit - matchStart;
+        }
+    }
+    
+    text.handleReplaceBetween(start, limit, EMPTY); // delete original text
+    
+    return outLen;
+}
+
+/**
+ * UnicodeReplacer API
+ */
+UnicodeString& StringMatcher::toReplacerPattern(UnicodeString& rule,
+                                                UBool /*escapeUnprintable*/) const {
+    // assert(segmentNumber > 0);
+    rule.truncate(0);
+    rule.append((UChar)0x0024 /*$*/);
+    ICU_Utility::appendNumber(rule, segmentNumber, 10, 1);
+    return rule;
+}
+
+/**
+ * Remove any match info.  This must be called before performing a
+ * set of matches with this segment.
+ */
+ void StringMatcher::resetMatch() {
+    matchStart = matchLimit = -1;
+}
+
+/**
+ * Union the set of all characters that may output by this object
+ * into the given set.
+ * @param toUnionTo the set into which to union the output characters
+ */
+void StringMatcher::addReplacementSetTo(UnicodeSet& /*toUnionTo*/) const {
+    // The output of this replacer varies; it is the source text between
+    // matchStart and matchLimit.  Since this varies depending on the
+    // input text, we can't compute it here.  We can either do nothing
+    // or we can add ALL characters to the set.  It's probably more useful
+    // to do nothing.
+}
+
+/**
+ * Implement UnicodeFunctor
+ */
+void StringMatcher::setData(const TransliterationRuleData* d) {
+    data = d;
+    int32_t i = 0;
+    while (i<pattern.length()) {
+        UChar32 c = pattern.char32At(i);
+        UnicodeFunctor* f = data->lookup(c);
+        if (f != NULL) {
+            f->setData(data);
+        }
+        i += UTF_CHAR_LENGTH(c);
+    }    
+}
+
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_TRANSLITERATION */
+
+//eof