Check in the pristine copy of ICU 4.6...

icu46/source/i18n/rbt_set.cpp

+/*
+ **********************************************************************
+ *   Copyright (C) 1999-2008, 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/unistr.h"
+#include "unicode/uniset.h"
+#include "rbt_set.h"
+#include "rbt_rule.h"
+#include "cmemory.h"
+#include "putilimp.h"
+
+U_CDECL_BEGIN
+static void U_CALLCONV _deleteRule(void *rule) {
+    delete (U_NAMESPACE_QUALIFIER TransliterationRule *)rule;
+}
+U_CDECL_END
+
+//----------------------------------------------------------------------
+// BEGIN Debugging support
+//----------------------------------------------------------------------
+
+// #define DEBUG_RBT
+
+#ifdef DEBUG_RBT
+#include <stdio.h>
+#include "charstr.h"
+
+/**
+ * @param appendTo result is appended to this param.
+ * @param input the string being transliterated
+ * @param pos the index struct
+ */
+static UnicodeString& _formatInput(UnicodeString &appendTo,
+                                   const UnicodeString& input,
+                                   const UTransPosition& pos) {
+    // Output a string of the form aaa{bbb|ccc|ddd}eee, where
+    // the {} indicate the context start and limit, and the ||
+    // indicate the start and limit.
+    if (0 <= pos.contextStart &&
+        pos.contextStart <= pos.start &&
+        pos.start <= pos.limit &&
+        pos.limit <= pos.contextLimit &&
+        pos.contextLimit <= input.length()) {
+
+        UnicodeString a, b, c, d, e;
+        input.extractBetween(0, pos.contextStart, a);
+        input.extractBetween(pos.contextStart, pos.start, b);
+        input.extractBetween(pos.start, pos.limit, c);
+        input.extractBetween(pos.limit, pos.contextLimit, d);
+        input.extractBetween(pos.contextLimit, input.length(), e);
+        appendTo.append(a).append((UChar)123/*{*/).append(b).
+            append((UChar)124/*|*/).append(c).append((UChar)124/*|*/).append(d).
+            append((UChar)125/*}*/).append(e);
+    } else {
+        appendTo.append("INVALID UTransPosition");
+        //appendTo.append((UnicodeString)"INVALID UTransPosition {cs=" +
+        //                pos.contextStart + ", s=" + pos.start + ", l=" +
+        //                pos.limit + ", cl=" + pos.contextLimit + "} on " +
+        //                input);
+    }
+    return appendTo;
+}
+
+// Append a hex string to the target
+UnicodeString& _appendHex(uint32_t number,
+                          int32_t digits,
+                          UnicodeString& target) {
+    static const UChar digitString[] = {
+        0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
+        0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0
+    };
+    while (digits--) {
+        target += digitString[(number >> (digits*4)) & 0xF];
+    }
+    return target;
+}
+
+// Replace nonprintable characters with unicode escapes
+UnicodeString& _escape(const UnicodeString &source,
+                       UnicodeString &target) {
+    for (int32_t i = 0; i < source.length(); ) {
+        UChar32 ch = source.char32At(i);
+        i += UTF_CHAR_LENGTH(ch);
+        if (ch < 0x09 || (ch > 0x0A && ch < 0x20)|| ch > 0x7E) {
+            if (ch <= 0xFFFF) {
+                target += "\\u";
+                _appendHex(ch, 4, target);
+            } else {
+                target += "\\U";
+                _appendHex(ch, 8, target);
+            }
+        } else {
+            target += ch;
+        }
+    }
+    return target;
+}
+
+inline void _debugOut(const char* msg, TransliterationRule* rule,
+                      const Replaceable& theText, UTransPosition& pos) {
+    UnicodeString buf(msg, "");
+    if (rule) {
+        UnicodeString r;
+        rule->toRule(r, TRUE);
+        buf.append((UChar)32).append(r);
+    }
+    buf.append(UnicodeString(" => ", ""));
+    UnicodeString* text = (UnicodeString*)&theText;
+    _formatInput(buf, *text, pos);
+    UnicodeString esc;
+    _escape(buf, esc);
+    CharString cbuf(esc);
+    printf("%s\n", (const char*) cbuf);
+}
+
+#else
+#define _debugOut(msg, rule, theText, pos)
+#endif
+
+//----------------------------------------------------------------------
+// END Debugging support
+//----------------------------------------------------------------------
+
+// Fill the precontext and postcontext with the patterns of the rules
+// that are masking one another.
+static void maskingError(const U_NAMESPACE_QUALIFIER TransliterationRule& rule1,
+                         const U_NAMESPACE_QUALIFIER TransliterationRule& rule2,
+                         UParseError& parseError) {
+    U_NAMESPACE_QUALIFIER UnicodeString r;
+    int32_t len;
+
+    parseError.line = parseError.offset = -1;
+    
+    // for pre-context
+    rule1.toRule(r, FALSE);
+    len = uprv_min(r.length(), U_PARSE_CONTEXT_LEN-1);
+    r.extract(0, len, parseError.preContext);
+    parseError.preContext[len] = 0;   
+    
+    //for post-context
+    r.truncate(0);
+    rule2.toRule(r, FALSE);
+    len = uprv_min(r.length(), U_PARSE_CONTEXT_LEN-1);
+    r.extract(0, len, parseError.postContext);
+    parseError.postContext[len] = 0;   
+}
+
+U_NAMESPACE_BEGIN
+
+/**
+ * Construct a new empty rule set.
+ */
+TransliterationRuleSet::TransliterationRuleSet(UErrorCode& status) : UMemory() {
+    ruleVector = new UVector(&_deleteRule, NULL, status);
+    if (U_FAILURE(status)) {
+        return;
+    }
+    if (ruleVector == NULL) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+    }
+    rules = NULL;
+    maxContextLength = 0;
+}
+
+/**
+ * Copy constructor.
+ */
+TransliterationRuleSet::TransliterationRuleSet(const TransliterationRuleSet& other) :
+    UMemory(other),
+    ruleVector(0),
+    rules(0),
+    maxContextLength(other.maxContextLength) {
+
+    int32_t i, len;
+    uprv_memcpy(index, other.index, sizeof(index));
+    UErrorCode status = U_ZERO_ERROR;
+    ruleVector = new UVector(&_deleteRule, NULL, status);
+    if (other.ruleVector != 0 && ruleVector != 0 && U_SUCCESS(status)) {
+        len = other.ruleVector->size();
+        for (i=0; i<len && U_SUCCESS(status); ++i) {
+            TransliterationRule *tempTranslitRule = new TransliterationRule(*(TransliterationRule*)other.ruleVector->elementAt(i));
+            // Null pointer test
+            if (tempTranslitRule == NULL) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                break;
+            }
+            ruleVector->addElement(tempTranslitRule, status);
+            if (U_FAILURE(status)) {
+                break;
+            }
+        }
+    }
+    if (other.rules != 0 && U_SUCCESS(status)) {
+        UParseError p;
+        freeze(p, status);
+    }
+}
+
+/**
+ * Destructor.
+ */
+TransliterationRuleSet::~TransliterationRuleSet() {
+    delete ruleVector; // This deletes the contained rules
+    uprv_free(rules);
+}
+
+void TransliterationRuleSet::setData(const TransliterationRuleData* d) {
+    /**
+     * We assume that the ruleset has already been frozen.
+     */
+    int32_t len = index[256]; // see freeze()
+    for (int32_t i=0; i<len; ++i) {
+        rules[i]->setData(d);
+    }
+}
+
+/**
+ * Return the maximum context length.
+ * @return the length of the longest preceding context.
+ */
+int32_t TransliterationRuleSet::getMaximumContextLength(void) const {
+    return maxContextLength;
+}
+
+/**
+ * Add a rule to this set.  Rules are added in order, and order is
+ * significant.  The last call to this method must be followed by
+ * a call to <code>freeze()</code> before the rule set is used.
+ *
+ * <p>If freeze() has already been called, calling addRule()
+ * unfreezes the rules, and freeze() must be called again.
+ *
+ * @param adoptedRule the rule to add
+ */
+void TransliterationRuleSet::addRule(TransliterationRule* adoptedRule,
+                                     UErrorCode& status) {
+    if (U_FAILURE(status)) {
+        delete adoptedRule;
+        return;
+    }
+    ruleVector->addElement(adoptedRule, status);
+
+    int32_t len;
+    if ((len = adoptedRule->getContextLength()) > maxContextLength) {
+        maxContextLength = len;
+    }
+
+    uprv_free(rules);
+    rules = 0;
+}
+
+/**
+ * Check this for masked rules and index it to optimize performance.
+ * The sequence of operations is: (1) add rules to a set using
+ * <code>addRule()</code>; (2) freeze the set using
+ * <code>freeze()</code>; (3) use the rule set.  If
+ * <code>addRule()</code> is called after calling this method, it
+ * invalidates this object, and this method must be called again.
+ * That is, <code>freeze()</code> may be called multiple times,
+ * although for optimal performance it shouldn't be.
+ */
+void TransliterationRuleSet::freeze(UParseError& parseError,UErrorCode& status) {
+    /* Construct the rule array and index table.  We reorder the
+     * rules by sorting them into 256 bins.  Each bin contains all
+     * rules matching the index value for that bin.  A rule
+     * matches an index value if string whose first key character
+     * has a low byte equal to the index value can match the rule.
+     *
+     * Each bin contains zero or more rules, in the same order
+     * they were found originally.  However, the total rules in
+     * the bins may exceed the number in the original vector,
+     * since rules that have a variable as their first key
+     * character will generally fall into more than one bin.
+     *
+     * That is, each bin contains all rules that either have that
+     * first index value as their first key character, or have
+     * a set containing the index value as their first character.
+     */
+    int32_t n = ruleVector->size();
+    int32_t j;
+    int16_t x;
+    UVector v(2*n, status); // heuristic; adjust as needed
+
+    if (U_FAILURE(status)) {
+        return;
+    }
+
+    /* Precompute the index values.  This saves a LOT of time.
+     * Be careful not to call malloc(0).
+     */
+    int16_t* indexValue = (int16_t*) uprv_malloc( sizeof(int16_t) * (n > 0 ? n : 1) );
+    /* test for NULL */
+    if (indexValue == 0) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+        return;
+    }
+    for (j=0; j<n; ++j) {
+        TransliterationRule* r = (TransliterationRule*) ruleVector->elementAt(j);
+        indexValue[j] = r->getIndexValue();
+    }
+    for (x=0; x<256; ++x) {
+        index[x] = v.size();
+        for (j=0; j<n; ++j) {
+            if (indexValue[j] >= 0) {
+                if (indexValue[j] == x) {
+                    v.addElement(ruleVector->elementAt(j), status);
+                }
+            } else {
+                // If the indexValue is < 0, then the first key character is
+                // a set, and we must use the more time-consuming
+                // matchesIndexValue check.  In practice this happens
+                // rarely, so we seldom tread this code path.
+                TransliterationRule* r = (TransliterationRule*) ruleVector->elementAt(j);
+                if (r->matchesIndexValue((uint8_t)x)) {
+                    v.addElement(r, status);
+                }
+            }
+        }
+    }
+    uprv_free(indexValue);
+    index[256] = v.size();
+
+    /* Freeze things into an array.
+     */
+    uprv_free(rules); // Contains alias pointers
+
+    /* You can't do malloc(0)! */
+    if (v.size() == 0) {
+        rules = NULL;
+        return;
+    }
+    rules = (TransliterationRule **)uprv_malloc(v.size() * sizeof(TransliterationRule *));
+    /* test for NULL */
+    if (rules == 0) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+        return;
+    }
+    for (j=0; j<v.size(); ++j) {
+        rules[j] = (TransliterationRule*) v.elementAt(j);
+    }
+
+    // TODO Add error reporting that indicates the rules that
+    //      are being masked.
+    //UnicodeString errors;
+
+    /* Check for masking.  This is MUCH faster than our old check,
+     * which was each rule against each following rule, since we
+     * only have to check for masking within each bin now.  It's
+     * 256*O(n2^2) instead of O(n1^2), where n1 is the total rule
+     * count, and n2 is the per-bin rule count.  But n2<<n1, so
+     * it's a big win.
+     */
+    for (x=0; x<256; ++x) {
+        for (j=index[x]; j<index[x+1]-1; ++j) {
+            TransliterationRule* r1 = rules[j];
+            for (int32_t k=j+1; k<index[x+1]; ++k) {
+                TransliterationRule* r2 = rules[k];
+                if (r1->masks(*r2)) {
+//|                 if (errors == null) {
+//|                     errors = new StringBuffer();
+//|                 } else {
+//|                     errors.append("\n");
+//|                 }
+//|                 errors.append("Rule " + r1 + " masks " + r2);
+                    status = U_RULE_MASK_ERROR;
+                    maskingError(*r1, *r2, parseError);
+                    return;
+                }
+            }
+        }
+    }
+
+    //if (errors != null) {
+    //    throw new IllegalArgumentException(errors.toString());
+    //}
+}
+
+/**
+ * Transliterate the given text with the given UTransPosition
+ * indices.  Return TRUE if the transliteration should continue
+ * or FALSE if it should halt (because of a U_PARTIAL_MATCH match).
+ * Note that FALSE is only ever returned if isIncremental is TRUE.
+ * @param text the text to be transliterated
+ * @param pos the position indices, which will be updated
+ * @param incremental if TRUE, assume new text may be inserted
+ * at index.limit, and return FALSE if thre is a partial match.
+ * @return TRUE unless a U_PARTIAL_MATCH has been obtained,
+ * indicating that transliteration should stop until more text
+ * arrives.
+ */
+UBool TransliterationRuleSet::transliterate(Replaceable& text,
+                                            UTransPosition& pos,
+                                            UBool incremental) {
+    int16_t indexByte = (int16_t) (text.char32At(pos.start) & 0xFF);
+    for (int32_t i=index[indexByte]; i<index[indexByte+1]; ++i) {
+        UMatchDegree m = rules[i]->matchAndReplace(text, pos, incremental);
+        switch (m) {
+        case U_MATCH:
+            _debugOut("match", rules[i], text, pos);
+            return TRUE;
+        case U_PARTIAL_MATCH:
+            _debugOut("partial match", rules[i], text, pos);
+            return FALSE;
+        default: /* Ram: added default to make GCC happy */
+            break;
+        }
+    }
+    // No match or partial match from any rule
+    pos.start += UTF_CHAR_LENGTH(text.char32At(pos.start));
+    _debugOut("no match", NULL, text, pos);
+    return TRUE;
+}
+
+/**
+ * Create rule strings that represents this rule set.
+ */
+UnicodeString& TransliterationRuleSet::toRules(UnicodeString& ruleSource,
+                                               UBool escapeUnprintable) const {
+    int32_t i;
+    int32_t count = ruleVector->size();
+    ruleSource.truncate(0);
+    for (i=0; i<count; ++i) {
+        if (i != 0) {
+            ruleSource.append((UChar) 0x000A /*\n*/);
+        }
+        TransliterationRule *r =
+            (TransliterationRule*) ruleVector->elementAt(i);
+        r->toRule(ruleSource, escapeUnprintable);
+    }
+    return ruleSource;
+}
+
+/**
+ * Return the set of all characters that may be modified
+ * (getTarget=false) or emitted (getTarget=true) by this set.
+ */
+UnicodeSet& TransliterationRuleSet::getSourceTargetSet(UnicodeSet& result,
+                               UBool getTarget) const
+{
+    result.clear();
+    int32_t count = ruleVector->size();
+    for (int32_t i=0; i<count; ++i) {
+        TransliterationRule* r =
+            (TransliterationRule*) ruleVector->elementAt(i);
+        if (getTarget) {
+            r->addTargetSetTo(result);
+        } else {
+            r->addSourceSetTo(result);
+        }
+    }
+    return result;
+}
+
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_TRANSLITERATION */