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      1 /*
      2 ******************************************************************************
      3 *   Copyright (C) 1997-2014, International Business Machines
      4 *   Corporation and others.  All Rights Reserved.
      5 ******************************************************************************
      6 *   file name:  nfrule.cpp
      7 *   encoding:   US-ASCII
      8 *   tab size:   8 (not used)
      9 *   indentation:4
     10 *
     11 * Modification history
     12 * Date        Name      Comments
     13 * 10/11/2001  Doug      Ported from ICU4J
     14 */
     15 
     16 #include "nfrule.h"
     17 
     18 #if U_HAVE_RBNF
     19 
     20 #include "unicode/localpointer.h"
     21 #include "unicode/rbnf.h"
     22 #include "unicode/tblcoll.h"
     23 #include "unicode/coleitr.h"
     24 #include "unicode/uchar.h"
     25 #include "nfrs.h"
     26 #include "nfrlist.h"
     27 #include "nfsubs.h"
     28 #include "patternprops.h"
     29 
     30 U_NAMESPACE_BEGIN
     31 
     32 NFRule::NFRule(const RuleBasedNumberFormat* _rbnf)
     33   : baseValue((int32_t)0)
     34   , radix(0)
     35   , exponent(0)
     36   , ruleText()
     37   , sub1(NULL)
     38   , sub2(NULL)
     39   , formatter(_rbnf)
     40 {
     41 }
     42 
     43 NFRule::~NFRule()
     44 {
     45   delete sub1;
     46   delete sub2;
     47 }
     48 
     49 static const UChar gLeftBracket = 0x005b;
     50 static const UChar gRightBracket = 0x005d;
     51 static const UChar gColon = 0x003a;
     52 static const UChar gZero = 0x0030;
     53 static const UChar gNine = 0x0039;
     54 static const UChar gSpace = 0x0020;
     55 static const UChar gSlash = 0x002f;
     56 static const UChar gGreaterThan = 0x003e;
     57 static const UChar gLessThan = 0x003c;
     58 static const UChar gComma = 0x002c;
     59 static const UChar gDot = 0x002e;
     60 static const UChar gTick = 0x0027;
     61 //static const UChar gMinus = 0x002d;
     62 static const UChar gSemicolon = 0x003b;
     63 
     64 static const UChar gMinusX[] =                  {0x2D, 0x78, 0};    /* "-x" */
     65 static const UChar gXDotX[] =                   {0x78, 0x2E, 0x78, 0}; /* "x.x" */
     66 static const UChar gXDotZero[] =                {0x78, 0x2E, 0x30, 0}; /* "x.0" */
     67 static const UChar gZeroDotX[] =                {0x30, 0x2E, 0x78, 0}; /* "0.x" */
     68 
     69 static const UChar gLessLess[] =                {0x3C, 0x3C, 0};    /* "<<" */
     70 static const UChar gLessPercent[] =             {0x3C, 0x25, 0};    /* "<%" */
     71 static const UChar gLessHash[] =                {0x3C, 0x23, 0};    /* "<#" */
     72 static const UChar gLessZero[] =                {0x3C, 0x30, 0};    /* "<0" */
     73 static const UChar gGreaterGreater[] =          {0x3E, 0x3E, 0};    /* ">>" */
     74 static const UChar gGreaterPercent[] =          {0x3E, 0x25, 0};    /* ">%" */
     75 static const UChar gGreaterHash[] =             {0x3E, 0x23, 0};    /* ">#" */
     76 static const UChar gGreaterZero[] =             {0x3E, 0x30, 0};    /* ">0" */
     77 static const UChar gEqualPercent[] =            {0x3D, 0x25, 0};    /* "=%" */
     78 static const UChar gEqualHash[] =               {0x3D, 0x23, 0};    /* "=#" */
     79 static const UChar gEqualZero[] =               {0x3D, 0x30, 0};    /* "=0" */
     80 static const UChar gGreaterGreaterGreater[] =   {0x3E, 0x3E, 0x3E, 0}; /* ">>>" */
     81 
     82 static const UChar * const tokenStrings[] = {
     83     gLessLess, gLessPercent, gLessHash, gLessZero,
     84     gGreaterGreater, gGreaterPercent,gGreaterHash, gGreaterZero,
     85     gEqualPercent, gEqualHash, gEqualZero, NULL
     86 };
     87 
     88 void
     89 NFRule::makeRules(UnicodeString& description,
     90                   const NFRuleSet *ruleSet,
     91                   const NFRule *predecessor,
     92                   const RuleBasedNumberFormat *rbnf,
     93                   NFRuleList& rules,
     94                   UErrorCode& status)
     95 {
     96     // we know we're making at least one rule, so go ahead and
     97     // new it up and initialize its basevalue and divisor
     98     // (this also strips the rule descriptor, if any, off the
     99     // descripton string)
    100     NFRule* rule1 = new NFRule(rbnf);
    101     /* test for NULL */
    102     if (rule1 == 0) {
    103         status = U_MEMORY_ALLOCATION_ERROR;
    104         return;
    105     }
    106     rule1->parseRuleDescriptor(description, status);
    107 
    108     // check the description to see whether there's text enclosed
    109     // in brackets
    110     int32_t brack1 = description.indexOf(gLeftBracket);
    111     int32_t brack2 = description.indexOf(gRightBracket);
    112 
    113     // if the description doesn't contain a matched pair of brackets,
    114     // or if it's of a type that doesn't recognize bracketed text,
    115     // then leave the description alone, initialize the rule's
    116     // rule text and substitutions, and return that rule
    117     if (brack1 == -1 || brack2 == -1 || brack1 > brack2
    118         || rule1->getType() == kProperFractionRule
    119         || rule1->getType() == kNegativeNumberRule) {
    120         rule1->ruleText = description;
    121         rule1->extractSubstitutions(ruleSet, predecessor, rbnf, status);
    122         rules.add(rule1);
    123     } else {
    124         // if the description does contain a matched pair of brackets,
    125         // then it's really shorthand for two rules (with one exception)
    126         NFRule* rule2 = NULL;
    127         UnicodeString sbuf;
    128 
    129         // we'll actually only split the rule into two rules if its
    130         // base value is an even multiple of its divisor (or it's one
    131         // of the special rules)
    132         if ((rule1->baseValue > 0
    133             && (rule1->baseValue % util64_pow(rule1->radix, rule1->exponent)) == 0)
    134             || rule1->getType() == kImproperFractionRule
    135             || rule1->getType() == kMasterRule) {
    136 
    137             // if it passes that test, new up the second rule.  If the
    138             // rule set both rules will belong to is a fraction rule
    139             // set, they both have the same base value; otherwise,
    140             // increment the original rule's base value ("rule1" actually
    141             // goes SECOND in the rule set's rule list)
    142             rule2 = new NFRule(rbnf);
    143             /* test for NULL */
    144             if (rule2 == 0) {
    145                 status = U_MEMORY_ALLOCATION_ERROR;
    146                 return;
    147             }
    148             if (rule1->baseValue >= 0) {
    149                 rule2->baseValue = rule1->baseValue;
    150                 if (!ruleSet->isFractionRuleSet()) {
    151                     ++rule1->baseValue;
    152                 }
    153             }
    154 
    155             // if the description began with "x.x" and contains bracketed
    156             // text, it describes both the improper fraction rule and
    157             // the proper fraction rule
    158             else if (rule1->getType() == kImproperFractionRule) {
    159                 rule2->setType(kProperFractionRule);
    160             }
    161 
    162             // if the description began with "x.0" and contains bracketed
    163             // text, it describes both the master rule and the
    164             // improper fraction rule
    165             else if (rule1->getType() == kMasterRule) {
    166                 rule2->baseValue = rule1->baseValue;
    167                 rule1->setType(kImproperFractionRule);
    168             }
    169 
    170             // both rules have the same radix and exponent (i.e., the
    171             // same divisor)
    172             rule2->radix = rule1->radix;
    173             rule2->exponent = rule1->exponent;
    174 
    175             // rule2's rule text omits the stuff in brackets: initalize
    176             // its rule text and substitutions accordingly
    177             sbuf.append(description, 0, brack1);
    178             if (brack2 + 1 < description.length()) {
    179                 sbuf.append(description, brack2 + 1, description.length() - brack2 - 1);
    180             }
    181             rule2->ruleText.setTo(sbuf);
    182             rule2->extractSubstitutions(ruleSet, predecessor, rbnf, status);
    183         }
    184 
    185         // rule1's text includes the text in the brackets but omits
    186         // the brackets themselves: initialize _its_ rule text and
    187         // substitutions accordingly
    188         sbuf.setTo(description, 0, brack1);
    189         sbuf.append(description, brack1 + 1, brack2 - brack1 - 1);
    190         if (brack2 + 1 < description.length()) {
    191             sbuf.append(description, brack2 + 1, description.length() - brack2 - 1);
    192         }
    193         rule1->ruleText.setTo(sbuf);
    194         rule1->extractSubstitutions(ruleSet, predecessor, rbnf, status);
    195 
    196         // if we only have one rule, return it; if we have two, return
    197         // a two-element array containing them (notice that rule2 goes
    198         // BEFORE rule1 in the list: in all cases, rule2 OMITS the
    199         // material in the brackets and rule1 INCLUDES the material
    200         // in the brackets)
    201         if (rule2 != NULL) {
    202             rules.add(rule2);
    203         }
    204         rules.add(rule1);
    205     }
    206 }
    207 
    208 /**
    209  * This function parses the rule's rule descriptor (i.e., the base
    210  * value and/or other tokens that precede the rule's rule text
    211  * in the description) and sets the rule's base value, radix, and
    212  * exponent according to the descriptor.  (If the description doesn't
    213  * include a rule descriptor, then this function sets everything to
    214  * default values and the rule set sets the rule's real base value).
    215  * @param description The rule's description
    216  * @return If "description" included a rule descriptor, this is
    217  * "description" with the descriptor and any trailing whitespace
    218  * stripped off.  Otherwise; it's "descriptor" unchangd.
    219  */
    220 void
    221 NFRule::parseRuleDescriptor(UnicodeString& description, UErrorCode& status)
    222 {
    223     // the description consists of a rule descriptor and a rule body,
    224     // separated by a colon.  The rule descriptor is optional.  If
    225     // it's omitted, just set the base value to 0.
    226     int32_t p = description.indexOf(gColon);
    227     if (p == -1) {
    228         setBaseValue((int32_t)0, status);
    229     } else {
    230         // copy the descriptor out into its own string and strip it,
    231         // along with any trailing whitespace, out of the original
    232         // description
    233         UnicodeString descriptor;
    234         descriptor.setTo(description, 0, p);
    235 
    236         ++p;
    237         while (p < description.length() && PatternProps::isWhiteSpace(description.charAt(p))) {
    238             ++p;
    239         }
    240         description.removeBetween(0, p);
    241 
    242         // check first to see if the rule descriptor matches the token
    243         // for one of the special rules.  If it does, set the base
    244         // value to the correct identfier value
    245         if (0 == descriptor.compare(gMinusX, 2)) {
    246             setType(kNegativeNumberRule);
    247         }
    248         else if (0 == descriptor.compare(gXDotX, 3)) {
    249             setType(kImproperFractionRule);
    250         }
    251         else if (0 == descriptor.compare(gZeroDotX, 3)) {
    252             setType(kProperFractionRule);
    253         }
    254         else if (0 == descriptor.compare(gXDotZero, 3)) {
    255             setType(kMasterRule);
    256         }
    257 
    258         // if the rule descriptor begins with a digit, it's a descriptor
    259         // for a normal rule
    260         // since we don't have Long.parseLong, and this isn't much work anyway,
    261         // just build up the value as we encounter the digits.
    262         else if (descriptor.charAt(0) >= gZero && descriptor.charAt(0) <= gNine) {
    263             int64_t val = 0;
    264             p = 0;
    265             UChar c = gSpace;
    266 
    267             // begin parsing the descriptor: copy digits
    268             // into "tempValue", skip periods, commas, and spaces,
    269             // stop on a slash or > sign (or at the end of the string),
    270             // and throw an exception on any other character
    271             int64_t ll_10 = 10;
    272             while (p < descriptor.length()) {
    273                 c = descriptor.charAt(p);
    274                 if (c >= gZero && c <= gNine) {
    275                     val = val * ll_10 + (int32_t)(c - gZero);
    276                 }
    277                 else if (c == gSlash || c == gGreaterThan) {
    278                     break;
    279                 }
    280                 else if (PatternProps::isWhiteSpace(c) || c == gComma || c == gDot) {
    281                 }
    282                 else {
    283                     // throw new IllegalArgumentException("Illegal character in rule descriptor");
    284                     status = U_PARSE_ERROR;
    285                     return;
    286                 }
    287                 ++p;
    288             }
    289 
    290             // we have the base value, so set it
    291             setBaseValue(val, status);
    292 
    293             // if we stopped the previous loop on a slash, we're
    294             // now parsing the rule's radix.  Again, accumulate digits
    295             // in tempValue, skip punctuation, stop on a > mark, and
    296             // throw an exception on anything else
    297             if (c == gSlash) {
    298                 val = 0;
    299                 ++p;
    300                 int64_t ll_10 = 10;
    301                 while (p < descriptor.length()) {
    302                     c = descriptor.charAt(p);
    303                     if (c >= gZero && c <= gNine) {
    304                         val = val * ll_10 + (int32_t)(c - gZero);
    305                     }
    306                     else if (c == gGreaterThan) {
    307                         break;
    308                     }
    309                     else if (PatternProps::isWhiteSpace(c) || c == gComma || c == gDot) {
    310                     }
    311                     else {
    312                         // throw new IllegalArgumentException("Illegal character is rule descriptor");
    313                         status = U_PARSE_ERROR;
    314                         return;
    315                     }
    316                     ++p;
    317                 }
    318 
    319                 // tempValue now contain's the rule's radix.  Set it
    320                 // accordingly, and recalculate the rule's exponent
    321                 radix = (int32_t)val;
    322                 if (radix == 0) {
    323                     // throw new IllegalArgumentException("Rule can't have radix of 0");
    324                     status = U_PARSE_ERROR;
    325                 }
    326 
    327                 exponent = expectedExponent();
    328             }
    329 
    330             // if we stopped the previous loop on a > sign, then continue
    331             // for as long as we still see > signs.  For each one,
    332             // decrement the exponent (unless the exponent is already 0).
    333             // If we see another character before reaching the end of
    334             // the descriptor, that's also a syntax error.
    335             if (c == gGreaterThan) {
    336                 while (p < descriptor.length()) {
    337                     c = descriptor.charAt(p);
    338                     if (c == gGreaterThan && exponent > 0) {
    339                         --exponent;
    340                     } else {
    341                         // throw new IllegalArgumentException("Illegal character in rule descriptor");
    342                         status = U_PARSE_ERROR;
    343                         return;
    344                     }
    345                     ++p;
    346                 }
    347             }
    348         }
    349     }
    350 
    351     // finally, if the rule body begins with an apostrophe, strip it off
    352     // (this is generally used to put whitespace at the beginning of
    353     // a rule's rule text)
    354     if (description.length() > 0 && description.charAt(0) == gTick) {
    355         description.removeBetween(0, 1);
    356     }
    357 
    358     // return the description with all the stuff we've just waded through
    359     // stripped off the front.  It now contains just the rule body.
    360     // return description;
    361 }
    362 
    363 /**
    364 * Searches the rule's rule text for the substitution tokens,
    365 * creates the substitutions, and removes the substitution tokens
    366 * from the rule's rule text.
    367 * @param owner The rule set containing this rule
    368 * @param predecessor The rule preseding this one in "owners" rule list
    369 * @param ownersOwner The RuleBasedFormat that owns this rule
    370 */
    371 void
    372 NFRule::extractSubstitutions(const NFRuleSet* ruleSet,
    373                              const NFRule* predecessor,
    374                              const RuleBasedNumberFormat* rbnf,
    375                              UErrorCode& status)
    376 {
    377     if (U_SUCCESS(status)) {
    378         sub1 = extractSubstitution(ruleSet, predecessor, rbnf, status);
    379         sub2 = extractSubstitution(ruleSet, predecessor, rbnf, status);
    380     }
    381 }
    382 
    383 /**
    384 * Searches the rule's rule text for the first substitution token,
    385 * creates a substitution based on it, and removes the token from
    386 * the rule's rule text.
    387 * @param owner The rule set containing this rule
    388 * @param predecessor The rule preceding this one in the rule set's
    389 * rule list
    390 * @param ownersOwner The RuleBasedNumberFormat that owns this rule
    391 * @return The newly-created substitution.  This is never null; if
    392 * the rule text doesn't contain any substitution tokens, this will
    393 * be a NullSubstitution.
    394 */
    395 NFSubstitution *
    396 NFRule::extractSubstitution(const NFRuleSet* ruleSet,
    397                             const NFRule* predecessor,
    398                             const RuleBasedNumberFormat* rbnf,
    399                             UErrorCode& status)
    400 {
    401     NFSubstitution* result = NULL;
    402 
    403     // search the rule's rule text for the first two characters of
    404     // a substitution token
    405     int32_t subStart = indexOfAny(tokenStrings);
    406     int32_t subEnd = subStart;
    407 
    408     // if we didn't find one, create a null substitution positioned
    409     // at the end of the rule text
    410     if (subStart == -1) {
    411         return NFSubstitution::makeSubstitution(ruleText.length(), this, predecessor,
    412             ruleSet, rbnf, UnicodeString(), status);
    413     }
    414 
    415     // special-case the ">>>" token, since searching for the > at the
    416     // end will actually find the > in the middle
    417     if (ruleText.indexOf(gGreaterGreaterGreater, 3, 0) == subStart) {
    418         subEnd = subStart + 2;
    419 
    420         // otherwise the substitution token ends with the same character
    421         // it began with
    422     } else {
    423         UChar c = ruleText.charAt(subStart);
    424         subEnd = ruleText.indexOf(c, subStart + 1);
    425         // special case for '<%foo<<'
    426         if (c == gLessThan && subEnd != -1 && subEnd < ruleText.length() - 1 && ruleText.charAt(subEnd+1) == c) {
    427             // ordinals use "=#,##0==%abbrev=" as their rule.  Notice that the '==' in the middle
    428             // occurs because of the juxtaposition of two different rules.  The check for '<' is a hack
    429             // to get around this.  Having the duplicate at the front would cause problems with
    430             // rules like "<<%" to format, say, percents...
    431             ++subEnd;
    432         }
    433    }
    434 
    435     // if we don't find the end of the token (i.e., if we're on a single,
    436     // unmatched token character), create a null substitution positioned
    437     // at the end of the rule
    438     if (subEnd == -1) {
    439         return NFSubstitution::makeSubstitution(ruleText.length(), this, predecessor,
    440             ruleSet, rbnf, UnicodeString(), status);
    441     }
    442 
    443     // if we get here, we have a real substitution token (or at least
    444     // some text bounded by substitution token characters).  Use
    445     // makeSubstitution() to create the right kind of substitution
    446     UnicodeString subToken;
    447     subToken.setTo(ruleText, subStart, subEnd + 1 - subStart);
    448     result = NFSubstitution::makeSubstitution(subStart, this, predecessor, ruleSet,
    449         rbnf, subToken, status);
    450 
    451     // remove the substitution from the rule text
    452     ruleText.removeBetween(subStart, subEnd+1);
    453 
    454     return result;
    455 }
    456 
    457 /**
    458  * Sets the rule's base value, and causes the radix and exponent
    459  * to be recalculated.  This is used during construction when we
    460  * don't know the rule's base value until after it's been
    461  * constructed.  It should be used at any other time.
    462  * @param The new base value for the rule.
    463  */
    464 void
    465 NFRule::setBaseValue(int64_t newBaseValue, UErrorCode& status)
    466 {
    467     // set the base value
    468     baseValue = newBaseValue;
    469 
    470     // if this isn't a special rule, recalculate the radix and exponent
    471     // (the radix always defaults to 10; if it's supposed to be something
    472     // else, it's cleaned up by the caller and the exponent is
    473     // recalculated again-- the only function that does this is
    474     // NFRule.parseRuleDescriptor() )
    475     if (baseValue >= 1) {
    476         radix = 10;
    477         exponent = expectedExponent();
    478 
    479         // this function gets called on a fully-constructed rule whose
    480         // description didn't specify a base value.  This means it
    481         // has substitutions, and some substitutions hold on to copies
    482         // of the rule's divisor.  Fix their copies of the divisor.
    483         if (sub1 != NULL) {
    484             sub1->setDivisor(radix, exponent, status);
    485         }
    486         if (sub2 != NULL) {
    487             sub2->setDivisor(radix, exponent, status);
    488         }
    489 
    490         // if this is a special rule, its radix and exponent are basically
    491         // ignored.  Set them to "safe" default values
    492     } else {
    493         radix = 10;
    494         exponent = 0;
    495     }
    496 }
    497 
    498 /**
    499 * This calculates the rule's exponent based on its radix and base
    500 * value.  This will be the highest power the radix can be raised to
    501 * and still produce a result less than or equal to the base value.
    502 */
    503 int16_t
    504 NFRule::expectedExponent() const
    505 {
    506     // since the log of 0, or the log base 0 of something, causes an
    507     // error, declare the exponent in these cases to be 0 (we also
    508     // deal with the special-rule identifiers here)
    509     if (radix == 0 || baseValue < 1) {
    510         return 0;
    511     }
    512 
    513     // we get rounding error in some cases-- for example, log 1000 / log 10
    514     // gives us 1.9999999996 instead of 2.  The extra logic here is to take
    515     // that into account
    516     int16_t tempResult = (int16_t)(uprv_log((double)baseValue) / uprv_log((double)radix));
    517     int64_t temp = util64_pow(radix, tempResult + 1);
    518     if (temp <= baseValue) {
    519         tempResult += 1;
    520     }
    521     return tempResult;
    522 }
    523 
    524 /**
    525  * Searches the rule's rule text for any of the specified strings.
    526  * @param strings An array of strings to search the rule's rule
    527  * text for
    528  * @return The index of the first match in the rule's rule text
    529  * (i.e., the first substring in the rule's rule text that matches
    530  * _any_ of the strings in "strings").  If none of the strings in
    531  * "strings" is found in the rule's rule text, returns -1.
    532  */
    533 int32_t
    534 NFRule::indexOfAny(const UChar* const strings[]) const
    535 {
    536     int result = -1;
    537     for (int i = 0; strings[i]; i++) {
    538         int32_t pos = ruleText.indexOf(*strings[i]);
    539         if (pos != -1 && (result == -1 || pos < result)) {
    540             result = pos;
    541         }
    542     }
    543     return result;
    544 }
    545 
    546 //-----------------------------------------------------------------------
    547 // boilerplate
    548 //-----------------------------------------------------------------------
    549 
    550 /**
    551 * Tests two rules for equality.
    552 * @param that The rule to compare this one against
    553 * @return True is the two rules are functionally equivalent
    554 */
    555 UBool
    556 NFRule::operator==(const NFRule& rhs) const
    557 {
    558     return baseValue == rhs.baseValue
    559         && radix == rhs.radix
    560         && exponent == rhs.exponent
    561         && ruleText == rhs.ruleText
    562         && *sub1 == *rhs.sub1
    563         && *sub2 == *rhs.sub2;
    564 }
    565 
    566 /**
    567 * Returns a textual representation of the rule.  This won't
    568 * necessarily be the same as the description that this rule
    569 * was created with, but it will produce the same result.
    570 * @return A textual description of the rule
    571 */
    572 static void util_append64(UnicodeString& result, int64_t n)
    573 {
    574     UChar buffer[256];
    575     int32_t len = util64_tou(n, buffer, sizeof(buffer));
    576     UnicodeString temp(buffer, len);
    577     result.append(temp);
    578 }
    579 
    580 void
    581 NFRule::_appendRuleText(UnicodeString& result) const
    582 {
    583     switch (getType()) {
    584     case kNegativeNumberRule: result.append(gMinusX, 2); break;
    585     case kImproperFractionRule: result.append(gXDotX, 3); break;
    586     case kProperFractionRule: result.append(gZeroDotX, 3); break;
    587     case kMasterRule: result.append(gXDotZero, 3); break;
    588     default:
    589         // for a normal rule, write out its base value, and if the radix is
    590         // something other than 10, write out the radix (with the preceding
    591         // slash, of course).  Then calculate the expected exponent and if
    592         // if isn't the same as the actual exponent, write an appropriate
    593         // number of > signs.  Finally, terminate the whole thing with
    594         // a colon.
    595         util_append64(result, baseValue);
    596         if (radix != 10) {
    597             result.append(gSlash);
    598             util_append64(result, radix);
    599         }
    600         int numCarets = expectedExponent() - exponent;
    601         for (int i = 0; i < numCarets; i++) {
    602             result.append(gGreaterThan);
    603         }
    604         break;
    605     }
    606     result.append(gColon);
    607     result.append(gSpace);
    608 
    609     // if the rule text begins with a space, write an apostrophe
    610     // (whitespace after the rule descriptor is ignored; the
    611     // apostrophe is used to make the whitespace significant)
    612     if (ruleText.charAt(0) == gSpace && sub1->getPos() != 0) {
    613         result.append(gTick);
    614     }
    615 
    616     // now, write the rule's rule text, inserting appropriate
    617     // substitution tokens in the appropriate places
    618     UnicodeString ruleTextCopy;
    619     ruleTextCopy.setTo(ruleText);
    620 
    621     UnicodeString temp;
    622     sub2->toString(temp);
    623     ruleTextCopy.insert(sub2->getPos(), temp);
    624     sub1->toString(temp);
    625     ruleTextCopy.insert(sub1->getPos(), temp);
    626 
    627     result.append(ruleTextCopy);
    628 
    629     // and finally, top the whole thing off with a semicolon and
    630     // return the result
    631     result.append(gSemicolon);
    632 }
    633 
    634 //-----------------------------------------------------------------------
    635 // formatting
    636 //-----------------------------------------------------------------------
    637 
    638 /**
    639 * Formats the number, and inserts the resulting text into
    640 * toInsertInto.
    641 * @param number The number being formatted
    642 * @param toInsertInto The string where the resultant text should
    643 * be inserted
    644 * @param pos The position in toInsertInto where the resultant text
    645 * should be inserted
    646 */
    647 void
    648 NFRule::doFormat(int64_t number, UnicodeString& toInsertInto, int32_t pos) const
    649 {
    650     // first, insert the rule's rule text into toInsertInto at the
    651     // specified position, then insert the results of the substitutions
    652     // into the right places in toInsertInto (notice we do the
    653     // substitutions in reverse order so that the offsets don't get
    654     // messed up)
    655     toInsertInto.insert(pos, ruleText);
    656     sub2->doSubstitution(number, toInsertInto, pos);
    657     sub1->doSubstitution(number, toInsertInto, pos);
    658 }
    659 
    660 /**
    661 * Formats the number, and inserts the resulting text into
    662 * toInsertInto.
    663 * @param number The number being formatted
    664 * @param toInsertInto The string where the resultant text should
    665 * be inserted
    666 * @param pos The position in toInsertInto where the resultant text
    667 * should be inserted
    668 */
    669 void
    670 NFRule::doFormat(double number, UnicodeString& toInsertInto, int32_t pos) const
    671 {
    672     // first, insert the rule's rule text into toInsertInto at the
    673     // specified position, then insert the results of the substitutions
    674     // into the right places in toInsertInto
    675     // [again, we have two copies of this routine that do the same thing
    676     // so that we don't sacrifice precision in a long by casting it
    677     // to a double]
    678     toInsertInto.insert(pos, ruleText);
    679     sub2->doSubstitution(number, toInsertInto, pos);
    680     sub1->doSubstitution(number, toInsertInto, pos);
    681 }
    682 
    683 /**
    684 * Used by the owning rule set to determine whether to invoke the
    685 * rollback rule (i.e., whether this rule or the one that precedes
    686 * it in the rule set's list should be used to format the number)
    687 * @param The number being formatted
    688 * @return True if the rule set should use the rule that precedes
    689 * this one in its list; false if it should use this rule
    690 */
    691 UBool
    692 NFRule::shouldRollBack(double number) const
    693 {
    694     // we roll back if the rule contains a modulus substitution,
    695     // the number being formatted is an even multiple of the rule's
    696     // divisor, and the rule's base value is NOT an even multiple
    697     // of its divisor
    698     // In other words, if the original description had
    699     //    100: << hundred[ >>];
    700     // that expands into
    701     //    100: << hundred;
    702     //    101: << hundred >>;
    703     // internally.  But when we're formatting 200, if we use the rule
    704     // at 101, which would normally apply, we get "two hundred zero".
    705     // To prevent this, we roll back and use the rule at 100 instead.
    706     // This is the logic that makes this happen: the rule at 101 has
    707     // a modulus substitution, its base value isn't an even multiple
    708     // of 100, and the value we're trying to format _is_ an even
    709     // multiple of 100.  This is called the "rollback rule."
    710     if ((sub1->isModulusSubstitution()) || (sub2->isModulusSubstitution())) {
    711         int64_t re = util64_pow(radix, exponent);
    712         return uprv_fmod(number, (double)re) == 0 && (baseValue % re) != 0;
    713     }
    714     return FALSE;
    715 }
    716 
    717 //-----------------------------------------------------------------------
    718 // parsing
    719 //-----------------------------------------------------------------------
    720 
    721 /**
    722 * Attempts to parse the string with this rule.
    723 * @param text The string being parsed
    724 * @param parsePosition On entry, the value is ignored and assumed to
    725 * be 0. On exit, this has been updated with the position of the first
    726 * character not consumed by matching the text against this rule
    727 * (if this rule doesn't match the text at all, the parse position
    728 * if left unchanged (presumably at 0) and the function returns
    729 * new Long(0)).
    730 * @param isFractionRule True if this rule is contained within a
    731 * fraction rule set.  This is only used if the rule has no
    732 * substitutions.
    733 * @return If this rule matched the text, this is the rule's base value
    734 * combined appropriately with the results of parsing the substitutions.
    735 * If nothing matched, this is new Long(0) and the parse position is
    736 * left unchanged.  The result will be an instance of Long if the
    737 * result is an integer and Double otherwise.  The result is never null.
    738 */
    739 #ifdef RBNF_DEBUG
    740 #include <stdio.h>
    741 
    742 static void dumpUS(FILE* f, const UnicodeString& us) {
    743   int len = us.length();
    744   char* buf = (char *)uprv_malloc((len+1)*sizeof(char)); //new char[len+1];
    745   if (buf != NULL) {
    746 	  us.extract(0, len, buf);
    747 	  buf[len] = 0;
    748 	  fprintf(f, "%s", buf);
    749 	  uprv_free(buf); //delete[] buf;
    750   }
    751 }
    752 #endif
    753 
    754 UBool
    755 NFRule::doParse(const UnicodeString& text,
    756                 ParsePosition& parsePosition,
    757                 UBool isFractionRule,
    758                 double upperBound,
    759                 Formattable& resVal) const
    760 {
    761     // internally we operate on a copy of the string being parsed
    762     // (because we're going to change it) and use our own ParsePosition
    763     ParsePosition pp;
    764     UnicodeString workText(text);
    765 
    766     // check to see whether the text before the first substitution
    767     // matches the text at the beginning of the string being
    768     // parsed.  If it does, strip that off the front of workText;
    769     // otherwise, dump out with a mismatch
    770     UnicodeString prefix;
    771     prefix.setTo(ruleText, 0, sub1->getPos());
    772 
    773 #ifdef RBNF_DEBUG
    774     fprintf(stderr, "doParse %x ", this);
    775     {
    776         UnicodeString rt;
    777         _appendRuleText(rt);
    778         dumpUS(stderr, rt);
    779     }
    780 
    781     fprintf(stderr, " text: '", this);
    782     dumpUS(stderr, text);
    783     fprintf(stderr, "' prefix: '");
    784     dumpUS(stderr, prefix);
    785 #endif
    786     stripPrefix(workText, prefix, pp);
    787     int32_t prefixLength = text.length() - workText.length();
    788 
    789 #ifdef RBNF_DEBUG
    790     fprintf(stderr, "' pl: %d ppi: %d s1p: %d\n", prefixLength, pp.getIndex(), sub1->getPos());
    791 #endif
    792 
    793     if (pp.getIndex() == 0 && sub1->getPos() != 0) {
    794         // commented out because ParsePosition doesn't have error index in 1.1.x
    795         // restored for ICU4C port
    796         parsePosition.setErrorIndex(pp.getErrorIndex());
    797         resVal.setLong(0);
    798         return TRUE;
    799     }
    800 
    801     // this is the fun part.  The basic guts of the rule-matching
    802     // logic is matchToDelimiter(), which is called twice.  The first
    803     // time it searches the input string for the rule text BETWEEN
    804     // the substitutions and tries to match the intervening text
    805     // in the input string with the first substitution.  If that
    806     // succeeds, it then calls it again, this time to look for the
    807     // rule text after the second substitution and to match the
    808     // intervening input text against the second substitution.
    809     //
    810     // For example, say we have a rule that looks like this:
    811     //    first << middle >> last;
    812     // and input text that looks like this:
    813     //    first one middle two last
    814     // First we use stripPrefix() to match "first " in both places and
    815     // strip it off the front, leaving
    816     //    one middle two last
    817     // Then we use matchToDelimiter() to match " middle " and try to
    818     // match "one" against a substitution.  If it's successful, we now
    819     // have
    820     //    two last
    821     // We use matchToDelimiter() a second time to match " last" and
    822     // try to match "two" against a substitution.  If "two" matches
    823     // the substitution, we have a successful parse.
    824     //
    825     // Since it's possible in many cases to find multiple instances
    826     // of each of these pieces of rule text in the input string,
    827     // we need to try all the possible combinations of these
    828     // locations.  This prevents us from prematurely declaring a mismatch,
    829     // and makes sure we match as much input text as we can.
    830     int highWaterMark = 0;
    831     double result = 0;
    832     int start = 0;
    833     double tempBaseValue = (double)(baseValue <= 0 ? 0 : baseValue);
    834 
    835     UnicodeString temp;
    836     do {
    837         // our partial parse result starts out as this rule's base
    838         // value.  If it finds a successful match, matchToDelimiter()
    839         // will compose this in some way with what it gets back from
    840         // the substitution, giving us a new partial parse result
    841         pp.setIndex(0);
    842 
    843         temp.setTo(ruleText, sub1->getPos(), sub2->getPos() - sub1->getPos());
    844         double partialResult = matchToDelimiter(workText, start, tempBaseValue,
    845             temp, pp, sub1,
    846             upperBound);
    847 
    848         // if we got a successful match (or were trying to match a
    849         // null substitution), pp is now pointing at the first unmatched
    850         // character.  Take note of that, and try matchToDelimiter()
    851         // on the input text again
    852         if (pp.getIndex() != 0 || sub1->isNullSubstitution()) {
    853             start = pp.getIndex();
    854 
    855             UnicodeString workText2;
    856             workText2.setTo(workText, pp.getIndex(), workText.length() - pp.getIndex());
    857             ParsePosition pp2;
    858 
    859             // the second matchToDelimiter() will compose our previous
    860             // partial result with whatever it gets back from its
    861             // substitution if there's a successful match, giving us
    862             // a real result
    863             temp.setTo(ruleText, sub2->getPos(), ruleText.length() - sub2->getPos());
    864             partialResult = matchToDelimiter(workText2, 0, partialResult,
    865                 temp, pp2, sub2,
    866                 upperBound);
    867 
    868             // if we got a successful match on this second
    869             // matchToDelimiter() call, update the high-water mark
    870             // and result (if necessary)
    871             if (pp2.getIndex() != 0 || sub2->isNullSubstitution()) {
    872                 if (prefixLength + pp.getIndex() + pp2.getIndex() > highWaterMark) {
    873                     highWaterMark = prefixLength + pp.getIndex() + pp2.getIndex();
    874                     result = partialResult;
    875                 }
    876             }
    877             // commented out because ParsePosition doesn't have error index in 1.1.x
    878             // restored for ICU4C port
    879             else {
    880                 int32_t temp = pp2.getErrorIndex() + sub1->getPos() + pp.getIndex();
    881                 if (temp> parsePosition.getErrorIndex()) {
    882                     parsePosition.setErrorIndex(temp);
    883                 }
    884             }
    885         }
    886         // commented out because ParsePosition doesn't have error index in 1.1.x
    887         // restored for ICU4C port
    888         else {
    889             int32_t temp = sub1->getPos() + pp.getErrorIndex();
    890             if (temp > parsePosition.getErrorIndex()) {
    891                 parsePosition.setErrorIndex(temp);
    892             }
    893         }
    894         // keep trying to match things until the outer matchToDelimiter()
    895         // call fails to make a match (each time, it picks up where it
    896         // left off the previous time)
    897     } while (sub1->getPos() != sub2->getPos()
    898         && pp.getIndex() > 0
    899         && pp.getIndex() < workText.length()
    900         && pp.getIndex() != start);
    901 
    902     // update the caller's ParsePosition with our high-water mark
    903     // (i.e., it now points at the first character this function
    904     // didn't match-- the ParsePosition is therefore unchanged if
    905     // we didn't match anything)
    906     parsePosition.setIndex(highWaterMark);
    907     // commented out because ParsePosition doesn't have error index in 1.1.x
    908     // restored for ICU4C port
    909     if (highWaterMark > 0) {
    910         parsePosition.setErrorIndex(0);
    911     }
    912 
    913     // this is a hack for one unusual condition: Normally, whether this
    914     // rule belong to a fraction rule set or not is handled by its
    915     // substitutions.  But if that rule HAS NO substitutions, then
    916     // we have to account for it here.  By definition, if the matching
    917     // rule in a fraction rule set has no substitutions, its numerator
    918     // is 1, and so the result is the reciprocal of its base value.
    919     if (isFractionRule &&
    920         highWaterMark > 0 &&
    921         sub1->isNullSubstitution()) {
    922         result = 1 / result;
    923     }
    924 
    925     resVal.setDouble(result);
    926     return TRUE; // ??? do we need to worry if it is a long or a double?
    927 }
    928 
    929 /**
    930 * This function is used by parse() to match the text being parsed
    931 * against a possible prefix string.  This function
    932 * matches characters from the beginning of the string being parsed
    933 * to characters from the prospective prefix.  If they match, pp is
    934 * updated to the first character not matched, and the result is
    935 * the unparsed part of the string.  If they don't match, the whole
    936 * string is returned, and pp is left unchanged.
    937 * @param text The string being parsed
    938 * @param prefix The text to match against
    939 * @param pp On entry, ignored and assumed to be 0.  On exit, points
    940 * to the first unmatched character (assuming the whole prefix matched),
    941 * or is unchanged (if the whole prefix didn't match).
    942 * @return If things match, this is the unparsed part of "text";
    943 * if they didn't match, this is "text".
    944 */
    945 void
    946 NFRule::stripPrefix(UnicodeString& text, const UnicodeString& prefix, ParsePosition& pp) const
    947 {
    948     // if the prefix text is empty, dump out without doing anything
    949     if (prefix.length() != 0) {
    950     	UErrorCode status = U_ZERO_ERROR;
    951         // use prefixLength() to match the beginning of
    952         // "text" against "prefix".  This function returns the
    953         // number of characters from "text" that matched (or 0 if
    954         // we didn't match the whole prefix)
    955         int32_t pfl = prefixLength(text, prefix, status);
    956         if (U_FAILURE(status)) { // Memory allocation error.
    957         	return;
    958         }
    959         if (pfl != 0) {
    960             // if we got a successful match, update the parse position
    961             // and strip the prefix off of "text"
    962             pp.setIndex(pp.getIndex() + pfl);
    963             text.remove(0, pfl);
    964         }
    965     }
    966 }
    967 
    968 /**
    969 * Used by parse() to match a substitution and any following text.
    970 * "text" is searched for instances of "delimiter".  For each instance
    971 * of delimiter, the intervening text is tested to see whether it
    972 * matches the substitution.  The longest match wins.
    973 * @param text The string being parsed
    974 * @param startPos The position in "text" where we should start looking
    975 * for "delimiter".
    976 * @param baseValue A partial parse result (often the rule's base value),
    977 * which is combined with the result from matching the substitution
    978 * @param delimiter The string to search "text" for.
    979 * @param pp Ignored and presumed to be 0 on entry.  If there's a match,
    980 * on exit this will point to the first unmatched character.
    981 * @param sub If we find "delimiter" in "text", this substitution is used
    982 * to match the text between the beginning of the string and the
    983 * position of "delimiter."  (If "delimiter" is the empty string, then
    984 * this function just matches against this substitution and updates
    985 * everything accordingly.)
    986 * @param upperBound When matching the substitution, it will only
    987 * consider rules with base values lower than this value.
    988 * @return If there's a match, this is the result of composing
    989 * baseValue with the result of matching the substitution.  Otherwise,
    990 * this is new Long(0).  It's never null.  If the result is an integer,
    991 * this will be an instance of Long; otherwise, it's an instance of
    992 * Double.
    993 *
    994 * !!! note {dlf} in point of fact, in the java code the caller always converts
    995 * the result to a double, so we might as well return one.
    996 */
    997 double
    998 NFRule::matchToDelimiter(const UnicodeString& text,
    999                          int32_t startPos,
   1000                          double _baseValue,
   1001                          const UnicodeString& delimiter,
   1002                          ParsePosition& pp,
   1003                          const NFSubstitution* sub,
   1004                          double upperBound) const
   1005 {
   1006 	UErrorCode status = U_ZERO_ERROR;
   1007     // if "delimiter" contains real (i.e., non-ignorable) text, search
   1008     // it for "delimiter" beginning at "start".  If that succeeds, then
   1009     // use "sub"'s doParse() method to match the text before the
   1010     // instance of "delimiter" we just found.
   1011     if (!allIgnorable(delimiter, status)) {
   1012     	if (U_FAILURE(status)) { //Memory allocation error.
   1013     		return 0;
   1014     	}
   1015         ParsePosition tempPP;
   1016         Formattable result;
   1017 
   1018         // use findText() to search for "delimiter".  It returns a two-
   1019         // element array: element 0 is the position of the match, and
   1020         // element 1 is the number of characters that matched
   1021         // "delimiter".
   1022         int32_t dLen;
   1023         int32_t dPos = findText(text, delimiter, startPos, &dLen);
   1024 
   1025         // if findText() succeeded, isolate the text preceding the
   1026         // match, and use "sub" to match that text
   1027         while (dPos >= 0) {
   1028             UnicodeString subText;
   1029             subText.setTo(text, 0, dPos);
   1030             if (subText.length() > 0) {
   1031                 UBool success = sub->doParse(subText, tempPP, _baseValue, upperBound,
   1032 #if UCONFIG_NO_COLLATION
   1033                     FALSE,
   1034 #else
   1035                     formatter->isLenient(),
   1036 #endif
   1037                     result);
   1038 
   1039                 // if the substitution could match all the text up to
   1040                 // where we found "delimiter", then this function has
   1041                 // a successful match.  Bump the caller's parse position
   1042                 // to point to the first character after the text
   1043                 // that matches "delimiter", and return the result
   1044                 // we got from parsing the substitution.
   1045                 if (success && tempPP.getIndex() == dPos) {
   1046                     pp.setIndex(dPos + dLen);
   1047                     return result.getDouble();
   1048                 }
   1049                 // commented out because ParsePosition doesn't have error index in 1.1.x
   1050                 // restored for ICU4C port
   1051                 else {
   1052                     if (tempPP.getErrorIndex() > 0) {
   1053                         pp.setErrorIndex(tempPP.getErrorIndex());
   1054                     } else {
   1055                         pp.setErrorIndex(tempPP.getIndex());
   1056                     }
   1057                 }
   1058             }
   1059 
   1060             // if we didn't match the substitution, search for another
   1061             // copy of "delimiter" in "text" and repeat the loop if
   1062             // we find it
   1063             tempPP.setIndex(0);
   1064             dPos = findText(text, delimiter, dPos + dLen, &dLen);
   1065         }
   1066         // if we make it here, this was an unsuccessful match, and we
   1067         // leave pp unchanged and return 0
   1068         pp.setIndex(0);
   1069         return 0;
   1070 
   1071         // if "delimiter" is empty, or consists only of ignorable characters
   1072         // (i.e., is semantically empty), thwe we obviously can't search
   1073         // for "delimiter".  Instead, just use "sub" to parse as much of
   1074         // "text" as possible.
   1075     } else {
   1076         ParsePosition tempPP;
   1077         Formattable result;
   1078 
   1079         // try to match the whole string against the substitution
   1080         UBool success = sub->doParse(text, tempPP, _baseValue, upperBound,
   1081 #if UCONFIG_NO_COLLATION
   1082             FALSE,
   1083 #else
   1084             formatter->isLenient(),
   1085 #endif
   1086             result);
   1087         if (success && (tempPP.getIndex() != 0 || sub->isNullSubstitution())) {
   1088             // if there's a successful match (or it's a null
   1089             // substitution), update pp to point to the first
   1090             // character we didn't match, and pass the result from
   1091             // sub.doParse() on through to the caller
   1092             pp.setIndex(tempPP.getIndex());
   1093             return result.getDouble();
   1094         }
   1095         // commented out because ParsePosition doesn't have error index in 1.1.x
   1096         // restored for ICU4C port
   1097         else {
   1098             pp.setErrorIndex(tempPP.getErrorIndex());
   1099         }
   1100 
   1101         // and if we get to here, then nothing matched, so we return
   1102         // 0 and leave pp alone
   1103         return 0;
   1104     }
   1105 }
   1106 
   1107 /**
   1108 * Used by stripPrefix() to match characters.  If lenient parse mode
   1109 * is off, this just calls startsWith().  If lenient parse mode is on,
   1110 * this function uses CollationElementIterators to match characters in
   1111 * the strings (only primary-order differences are significant in
   1112 * determining whether there's a match).
   1113 * @param str The string being tested
   1114 * @param prefix The text we're hoping to see at the beginning
   1115 * of "str"
   1116 * @return If "prefix" is found at the beginning of "str", this
   1117 * is the number of characters in "str" that were matched (this
   1118 * isn't necessarily the same as the length of "prefix" when matching
   1119 * text with a collator).  If there's no match, this is 0.
   1120 */
   1121 int32_t
   1122 NFRule::prefixLength(const UnicodeString& str, const UnicodeString& prefix, UErrorCode& status) const
   1123 {
   1124     // if we're looking for an empty prefix, it obviously matches
   1125     // zero characters.  Just go ahead and return 0.
   1126     if (prefix.length() == 0) {
   1127         return 0;
   1128     }
   1129 
   1130 #if !UCONFIG_NO_COLLATION
   1131     // go through all this grief if we're in lenient-parse mode
   1132     if (formatter->isLenient()) {
   1133         // get the formatter's collator and use it to create two
   1134         // collation element iterators, one over the target string
   1135         // and another over the prefix (right now, we'll throw an
   1136         // exception if the collator we get back from the formatter
   1137         // isn't a RuleBasedCollator, because RuleBasedCollator defines
   1138         // the CollationElementIterator protocol.  Hopefully, this
   1139         // will change someday.)
   1140         const RuleBasedCollator* collator = formatter->getCollator();
   1141         if (collator == NULL) {
   1142             status = U_MEMORY_ALLOCATION_ERROR;
   1143             return 0;
   1144         }
   1145         LocalPointer<CollationElementIterator> strIter(collator->createCollationElementIterator(str));
   1146         LocalPointer<CollationElementIterator> prefixIter(collator->createCollationElementIterator(prefix));
   1147         // Check for memory allocation error.
   1148         if (strIter.isNull() || prefixIter.isNull()) {
   1149             status = U_MEMORY_ALLOCATION_ERROR;
   1150             return 0;
   1151         }
   1152 
   1153         UErrorCode err = U_ZERO_ERROR;
   1154 
   1155         // The original code was problematic.  Consider this match:
   1156         // prefix = "fifty-"
   1157         // string = " fifty-7"
   1158         // The intent is to match string up to the '7', by matching 'fifty-' at position 1
   1159         // in the string.  Unfortunately, we were getting a match, and then computing where
   1160         // the match terminated by rematching the string.  The rematch code was using as an
   1161         // initial guess the substring of string between 0 and prefix.length.  Because of
   1162         // the leading space and trailing hyphen (both ignorable) this was succeeding, leaving
   1163         // the position before the hyphen in the string.  Recursing down, we then parsed the
   1164         // remaining string '-7' as numeric.  The resulting number turned out as 43 (50 - 7).
   1165         // This was not pretty, especially since the string "fifty-7" parsed just fine.
   1166         //
   1167         // We have newer APIs now, so we can use calls on the iterator to determine what we
   1168         // matched up to.  If we terminate because we hit the last element in the string,
   1169         // our match terminates at this length.  If we terminate because we hit the last element
   1170         // in the target, our match terminates at one before the element iterator position.
   1171 
   1172         // match collation elements between the strings
   1173         int32_t oStr = strIter->next(err);
   1174         int32_t oPrefix = prefixIter->next(err);
   1175 
   1176         while (oPrefix != CollationElementIterator::NULLORDER) {
   1177             // skip over ignorable characters in the target string
   1178             while (CollationElementIterator::primaryOrder(oStr) == 0
   1179                 && oStr != CollationElementIterator::NULLORDER) {
   1180                 oStr = strIter->next(err);
   1181             }
   1182 
   1183             // skip over ignorable characters in the prefix
   1184             while (CollationElementIterator::primaryOrder(oPrefix) == 0
   1185                 && oPrefix != CollationElementIterator::NULLORDER) {
   1186                 oPrefix = prefixIter->next(err);
   1187             }
   1188 
   1189             // dlf: move this above following test, if we consume the
   1190             // entire target, aren't we ok even if the source was also
   1191             // entirely consumed?
   1192 
   1193             // if skipping over ignorables brought to the end of
   1194             // the prefix, we DID match: drop out of the loop
   1195             if (oPrefix == CollationElementIterator::NULLORDER) {
   1196                 break;
   1197             }
   1198 
   1199             // if skipping over ignorables brought us to the end
   1200             // of the target string, we didn't match and return 0
   1201             if (oStr == CollationElementIterator::NULLORDER) {
   1202                 return 0;
   1203             }
   1204 
   1205             // match collation elements from the two strings
   1206             // (considering only primary differences).  If we
   1207             // get a mismatch, dump out and return 0
   1208             if (CollationElementIterator::primaryOrder(oStr)
   1209                 != CollationElementIterator::primaryOrder(oPrefix)) {
   1210                 return 0;
   1211 
   1212                 // otherwise, advance to the next character in each string
   1213                 // and loop (we drop out of the loop when we exhaust
   1214                 // collation elements in the prefix)
   1215             } else {
   1216                 oStr = strIter->next(err);
   1217                 oPrefix = prefixIter->next(err);
   1218             }
   1219         }
   1220 
   1221         int32_t result = strIter->getOffset();
   1222         if (oStr != CollationElementIterator::NULLORDER) {
   1223             --result; // back over character that we don't want to consume;
   1224         }
   1225 
   1226 #ifdef RBNF_DEBUG
   1227         fprintf(stderr, "prefix length: %d\n", result);
   1228 #endif
   1229         return result;
   1230 #if 0
   1231         //----------------------------------------------------------------
   1232         // JDK 1.2-specific API call
   1233         // return strIter.getOffset();
   1234         //----------------------------------------------------------------
   1235         // JDK 1.1 HACK (take out for 1.2-specific code)
   1236 
   1237         // if we make it to here, we have a successful match.  Now we
   1238         // have to find out HOW MANY characters from the target string
   1239         // matched the prefix (there isn't necessarily a one-to-one
   1240         // mapping between collation elements and characters).
   1241         // In JDK 1.2, there's a simple getOffset() call we can use.
   1242         // In JDK 1.1, on the other hand, we have to go through some
   1243         // ugly contortions.  First, use the collator to compare the
   1244         // same number of characters from the prefix and target string.
   1245         // If they're equal, we're done.
   1246         collator->setStrength(Collator::PRIMARY);
   1247         if (str.length() >= prefix.length()) {
   1248             UnicodeString temp;
   1249             temp.setTo(str, 0, prefix.length());
   1250             if (collator->equals(temp, prefix)) {
   1251 #ifdef RBNF_DEBUG
   1252                 fprintf(stderr, "returning: %d\n", prefix.length());
   1253 #endif
   1254                 return prefix.length();
   1255             }
   1256         }
   1257 
   1258         // if they're not equal, then we have to compare successively
   1259         // larger and larger substrings of the target string until we
   1260         // get to one that matches the prefix.  At that point, we know
   1261         // how many characters matched the prefix, and we can return.
   1262         int32_t p = 1;
   1263         while (p <= str.length()) {
   1264             UnicodeString temp;
   1265             temp.setTo(str, 0, p);
   1266             if (collator->equals(temp, prefix)) {
   1267                 return p;
   1268             } else {
   1269                 ++p;
   1270             }
   1271         }
   1272 
   1273         // SHOULD NEVER GET HERE!!!
   1274         return 0;
   1275         //----------------------------------------------------------------
   1276 #endif
   1277 
   1278         // If lenient parsing is turned off, forget all that crap above.
   1279         // Just use String.startsWith() and be done with it.
   1280   } else
   1281 #endif
   1282   {
   1283       if (str.startsWith(prefix)) {
   1284           return prefix.length();
   1285       } else {
   1286           return 0;
   1287       }
   1288   }
   1289 }
   1290 
   1291 /**
   1292 * Searches a string for another string.  If lenient parsing is off,
   1293 * this just calls indexOf().  If lenient parsing is on, this function
   1294 * uses CollationElementIterator to match characters, and only
   1295 * primary-order differences are significant in determining whether
   1296 * there's a match.
   1297 * @param str The string to search
   1298 * @param key The string to search "str" for
   1299 * @param startingAt The index into "str" where the search is to
   1300 * begin
   1301 * @return A two-element array of ints.  Element 0 is the position
   1302 * of the match, or -1 if there was no match.  Element 1 is the
   1303 * number of characters in "str" that matched (which isn't necessarily
   1304 * the same as the length of "key")
   1305 */
   1306 int32_t
   1307 NFRule::findText(const UnicodeString& str,
   1308                  const UnicodeString& key,
   1309                  int32_t startingAt,
   1310                  int32_t* length) const
   1311 {
   1312 #if !UCONFIG_NO_COLLATION
   1313     // if lenient parsing is turned off, this is easy: just call
   1314     // String.indexOf() and we're done
   1315     if (!formatter->isLenient()) {
   1316         *length = key.length();
   1317         return str.indexOf(key, startingAt);
   1318 
   1319         // but if lenient parsing is turned ON, we've got some work
   1320         // ahead of us
   1321     } else
   1322 #endif
   1323     {
   1324         //----------------------------------------------------------------
   1325         // JDK 1.1 HACK (take out of 1.2-specific code)
   1326 
   1327         // in JDK 1.2, CollationElementIterator provides us with an
   1328         // API to map between character offsets and collation elements
   1329         // and we can do this by marching through the string comparing
   1330         // collation elements.  We can't do that in JDK 1.1.  Insted,
   1331         // we have to go through this horrible slow mess:
   1332         int32_t p = startingAt;
   1333         int32_t keyLen = 0;
   1334 
   1335         // basically just isolate smaller and smaller substrings of
   1336         // the target string (each running to the end of the string,
   1337         // and with the first one running from startingAt to the end)
   1338         // and then use prefixLength() to see if the search key is at
   1339         // the beginning of each substring.  This is excruciatingly
   1340         // slow, but it will locate the key and tell use how long the
   1341         // matching text was.
   1342         UnicodeString temp;
   1343         UErrorCode status = U_ZERO_ERROR;
   1344         while (p < str.length() && keyLen == 0) {
   1345             temp.setTo(str, p, str.length() - p);
   1346             keyLen = prefixLength(temp, key, status);
   1347             if (U_FAILURE(status)) {
   1348             	break;
   1349             }
   1350             if (keyLen != 0) {
   1351                 *length = keyLen;
   1352                 return p;
   1353             }
   1354             ++p;
   1355         }
   1356         // if we make it to here, we didn't find it.  Return -1 for the
   1357         // location.  The length should be ignored, but set it to 0,
   1358         // which should be "safe"
   1359         *length = 0;
   1360         return -1;
   1361 
   1362         //----------------------------------------------------------------
   1363         // JDK 1.2 version of this routine
   1364         //RuleBasedCollator collator = (RuleBasedCollator)formatter.getCollator();
   1365         //
   1366         //CollationElementIterator strIter = collator.getCollationElementIterator(str);
   1367         //CollationElementIterator keyIter = collator.getCollationElementIterator(key);
   1368         //
   1369         //int keyStart = -1;
   1370         //
   1371         //str.setOffset(startingAt);
   1372         //
   1373         //int oStr = strIter.next();
   1374         //int oKey = keyIter.next();
   1375         //while (oKey != CollationElementIterator.NULLORDER) {
   1376         //    while (oStr != CollationElementIterator.NULLORDER &&
   1377         //                CollationElementIterator.primaryOrder(oStr) == 0)
   1378         //        oStr = strIter.next();
   1379         //
   1380         //    while (oKey != CollationElementIterator.NULLORDER &&
   1381         //                CollationElementIterator.primaryOrder(oKey) == 0)
   1382         //        oKey = keyIter.next();
   1383         //
   1384         //    if (oStr == CollationElementIterator.NULLORDER) {
   1385         //        return new int[] { -1, 0 };
   1386         //    }
   1387         //
   1388         //    if (oKey == CollationElementIterator.NULLORDER) {
   1389         //        break;
   1390         //    }
   1391         //
   1392         //    if (CollationElementIterator.primaryOrder(oStr) ==
   1393         //            CollationElementIterator.primaryOrder(oKey)) {
   1394         //        keyStart = strIter.getOffset();
   1395         //        oStr = strIter.next();
   1396         //        oKey = keyIter.next();
   1397         //    } else {
   1398         //        if (keyStart != -1) {
   1399         //            keyStart = -1;
   1400         //            keyIter.reset();
   1401         //        } else {
   1402         //            oStr = strIter.next();
   1403         //        }
   1404         //    }
   1405         //}
   1406         //
   1407         //if (oKey == CollationElementIterator.NULLORDER) {
   1408         //    return new int[] { keyStart, strIter.getOffset() - keyStart };
   1409         //} else {
   1410         //    return new int[] { -1, 0 };
   1411         //}
   1412     }
   1413 }
   1414 
   1415 /**
   1416 * Checks to see whether a string consists entirely of ignorable
   1417 * characters.
   1418 * @param str The string to test.
   1419 * @return true if the string is empty of consists entirely of
   1420 * characters that the number formatter's collator says are
   1421 * ignorable at the primary-order level.  false otherwise.
   1422 */
   1423 UBool
   1424 NFRule::allIgnorable(const UnicodeString& str, UErrorCode& status) const
   1425 {
   1426     // if the string is empty, we can just return true
   1427     if (str.length() == 0) {
   1428         return TRUE;
   1429     }
   1430 
   1431 #if !UCONFIG_NO_COLLATION
   1432     // if lenient parsing is turned on, walk through the string with
   1433     // a collation element iterator and make sure each collation
   1434     // element is 0 (ignorable) at the primary level
   1435     if (formatter->isLenient()) {
   1436         const RuleBasedCollator* collator = formatter->getCollator();
   1437         if (collator == NULL) {
   1438             status = U_MEMORY_ALLOCATION_ERROR;
   1439             return FALSE;
   1440         }
   1441         LocalPointer<CollationElementIterator> iter(collator->createCollationElementIterator(str));
   1442 
   1443         // Memory allocation error check.
   1444         if (iter.isNull()) {
   1445             status = U_MEMORY_ALLOCATION_ERROR;
   1446             return FALSE;
   1447         }
   1448 
   1449         UErrorCode err = U_ZERO_ERROR;
   1450         int32_t o = iter->next(err);
   1451         while (o != CollationElementIterator::NULLORDER
   1452             && CollationElementIterator::primaryOrder(o) == 0) {
   1453             o = iter->next(err);
   1454         }
   1455 
   1456         return o == CollationElementIterator::NULLORDER;
   1457     }
   1458 #endif
   1459 
   1460     // if lenient parsing is turned off, there is no such thing as
   1461     // an ignorable character: return true only if the string is empty
   1462     return FALSE;
   1463 }
   1464 
   1465 U_NAMESPACE_END
   1466 
   1467 /* U_HAVE_RBNF */
   1468 #endif
   1469