Home | History | Annotate | Download | only in common
      1 /*
      2 *******************************************************************************
      3 *   Copyright (C) 2011-2012, International Business Machines
      4 *   Corporation and others.  All Rights Reserved.
      5 *******************************************************************************
      6 *   file name:  messagepattern.cpp
      7 *   encoding:   US-ASCII
      8 *   tab size:   8 (not used)
      9 *   indentation:4
     10 *
     11 *   created on: 2011mar14
     12 *   created by: Markus W. Scherer
     13 */
     14 
     15 #include "unicode/utypes.h"
     16 
     17 #if !UCONFIG_NO_FORMATTING
     18 
     19 #include "unicode/messagepattern.h"
     20 #include "unicode/unistr.h"
     21 #include "unicode/utf16.h"
     22 #include "cmemory.h"
     23 #include "cstring.h"
     24 #include "messageimpl.h"
     25 #include "patternprops.h"
     26 #include "putilimp.h"
     27 #include "uassert.h"
     28 
     29 U_NAMESPACE_BEGIN
     30 
     31 // Unicode character/code point constants ---------------------------------- ***
     32 
     33 static const UChar u_pound=0x23;
     34 static const UChar u_apos=0x27;
     35 static const UChar u_plus=0x2B;
     36 static const UChar u_comma=0x2C;
     37 static const UChar u_minus=0x2D;
     38 static const UChar u_dot=0x2E;
     39 static const UChar u_colon=0x3A;
     40 static const UChar u_lessThan=0x3C;
     41 static const UChar u_equal=0x3D;
     42 static const UChar u_A=0x41;
     43 static const UChar u_C=0x43;
     44 static const UChar u_D=0x44;
     45 static const UChar u_E=0x45;
     46 static const UChar u_H=0x48;
     47 static const UChar u_I=0x49;
     48 static const UChar u_L=0x4C;
     49 static const UChar u_N=0x4E;
     50 static const UChar u_O=0x4F;
     51 static const UChar u_P=0x50;
     52 static const UChar u_R=0x52;
     53 static const UChar u_S=0x53;
     54 static const UChar u_T=0x54;
     55 static const UChar u_U=0x55;
     56 static const UChar u_Z=0x5A;
     57 static const UChar u_a=0x61;
     58 static const UChar u_c=0x63;
     59 static const UChar u_d=0x64;
     60 static const UChar u_e=0x65;
     61 static const UChar u_f=0x66;
     62 static const UChar u_h=0x68;
     63 static const UChar u_i=0x69;
     64 static const UChar u_l=0x6C;
     65 static const UChar u_n=0x6E;
     66 static const UChar u_o=0x6F;
     67 static const UChar u_p=0x70;
     68 static const UChar u_r=0x72;
     69 static const UChar u_s=0x73;
     70 static const UChar u_t=0x74;
     71 static const UChar u_u=0x75;
     72 static const UChar u_z=0x7A;
     73 static const UChar u_leftCurlyBrace=0x7B;
     74 static const UChar u_pipe=0x7C;
     75 static const UChar u_rightCurlyBrace=0x7D;
     76 static const UChar u_lessOrEqual=0x2264;  // U+2264 is <=
     77 
     78 static const UChar kOffsetColon[]={  // "offset:"
     79     u_o, u_f, u_f, u_s, u_e, u_t, u_colon
     80 };
     81 
     82 static const UChar kOther[]={  // "other"
     83     u_o, u_t, u_h, u_e, u_r
     84 };
     85 
     86 // MessagePatternList ------------------------------------------------------ ***
     87 
     88 template<typename T, int32_t stackCapacity>
     89 class MessagePatternList : public UMemory {
     90 public:
     91     MessagePatternList() {}
     92     void copyFrom(const MessagePatternList<T, stackCapacity> &other,
     93                   int32_t length,
     94                   UErrorCode &errorCode);
     95     UBool ensureCapacityForOneMore(int32_t oldLength, UErrorCode &errorCode);
     96     UBool equals(const MessagePatternList<T, stackCapacity> &other, int32_t length) const {
     97         for(int32_t i=0; i<length; ++i) {
     98             if(a[i]!=other.a[i]) { return FALSE; }
     99         }
    100         return TRUE;
    101     }
    102 
    103     MaybeStackArray<T, stackCapacity> a;
    104 };
    105 
    106 template<typename T, int32_t stackCapacity>
    107 void
    108 MessagePatternList<T, stackCapacity>::copyFrom(
    109         const MessagePatternList<T, stackCapacity> &other,
    110         int32_t length,
    111         UErrorCode &errorCode) {
    112     if(U_SUCCESS(errorCode) && length>0) {
    113         if(length>a.getCapacity() && NULL==a.resize(length)) {
    114             errorCode=U_MEMORY_ALLOCATION_ERROR;
    115             return;
    116         }
    117         uprv_memcpy(a.getAlias(), other.a.getAlias(), length*sizeof(T));
    118     }
    119 }
    120 
    121 template<typename T, int32_t stackCapacity>
    122 UBool
    123 MessagePatternList<T, stackCapacity>::ensureCapacityForOneMore(int32_t oldLength, UErrorCode &errorCode) {
    124     if(U_FAILURE(errorCode)) {
    125         return FALSE;
    126     }
    127     if(a.getCapacity()>oldLength || a.resize(2*oldLength, oldLength)!=NULL) {
    128         return TRUE;
    129     }
    130     errorCode=U_MEMORY_ALLOCATION_ERROR;
    131     return FALSE;
    132 }
    133 
    134 // MessagePatternList specializations -------------------------------------- ***
    135 
    136 class MessagePatternDoubleList : public MessagePatternList<double, 8> {
    137 };
    138 
    139 class MessagePatternPartsList : public MessagePatternList<MessagePattern::Part, 32> {
    140 };
    141 
    142 // MessagePattern constructors etc. ---------------------------------------- ***
    143 
    144 MessagePattern::MessagePattern(UErrorCode &errorCode)
    145         : aposMode(UCONFIG_MSGPAT_DEFAULT_APOSTROPHE_MODE),
    146           partsList(NULL), parts(NULL), partsLength(0),
    147           numericValuesList(NULL), numericValues(NULL), numericValuesLength(0),
    148           hasArgNames(FALSE), hasArgNumbers(FALSE), needsAutoQuoting(FALSE) {
    149     init(errorCode);
    150 }
    151 
    152 MessagePattern::MessagePattern(UMessagePatternApostropheMode mode, UErrorCode &errorCode)
    153         : aposMode(mode),
    154           partsList(NULL), parts(NULL), partsLength(0),
    155           numericValuesList(NULL), numericValues(NULL), numericValuesLength(0),
    156           hasArgNames(FALSE), hasArgNumbers(FALSE), needsAutoQuoting(FALSE) {
    157     init(errorCode);
    158 }
    159 
    160 MessagePattern::MessagePattern(const UnicodeString &pattern, UParseError *parseError, UErrorCode &errorCode)
    161         : aposMode(UCONFIG_MSGPAT_DEFAULT_APOSTROPHE_MODE),
    162           partsList(NULL), parts(NULL), partsLength(0),
    163           numericValuesList(NULL), numericValues(NULL), numericValuesLength(0),
    164           hasArgNames(FALSE), hasArgNumbers(FALSE), needsAutoQuoting(FALSE) {
    165     if(init(errorCode)) {
    166         parse(pattern, parseError, errorCode);
    167     }
    168 }
    169 
    170 UBool
    171 MessagePattern::init(UErrorCode &errorCode) {
    172     if(U_FAILURE(errorCode)) {
    173         return FALSE;
    174     }
    175     partsList=new MessagePatternPartsList();
    176     if(partsList==NULL) {
    177         errorCode=U_MEMORY_ALLOCATION_ERROR;
    178         return FALSE;
    179     }
    180     parts=partsList->a.getAlias();
    181     return TRUE;
    182 }
    183 
    184 MessagePattern::MessagePattern(const MessagePattern &other)
    185         : UObject(other), aposMode(other.aposMode), msg(other.msg),
    186           partsList(NULL), parts(NULL), partsLength(0),
    187           numericValuesList(NULL), numericValues(NULL), numericValuesLength(0),
    188           hasArgNames(other.hasArgNames), hasArgNumbers(other.hasArgNumbers),
    189           needsAutoQuoting(other.needsAutoQuoting) {
    190     UErrorCode errorCode=U_ZERO_ERROR;
    191     if(!copyStorage(other, errorCode)) {
    192         clear();
    193     }
    194 }
    195 
    196 MessagePattern &
    197 MessagePattern::operator=(const MessagePattern &other) {
    198     if(this==&other) {
    199         return *this;
    200     }
    201     aposMode=other.aposMode;
    202     msg=other.msg;
    203     hasArgNames=other.hasArgNames;
    204     hasArgNumbers=other.hasArgNumbers;
    205     needsAutoQuoting=other.needsAutoQuoting;
    206     UErrorCode errorCode=U_ZERO_ERROR;
    207     if(!copyStorage(other, errorCode)) {
    208         clear();
    209     }
    210     return *this;
    211 }
    212 
    213 UBool
    214 MessagePattern::copyStorage(const MessagePattern &other, UErrorCode &errorCode) {
    215     if(U_FAILURE(errorCode)) {
    216         return FALSE;
    217     }
    218     parts=NULL;
    219     partsLength=0;
    220     numericValues=NULL;
    221     numericValuesLength=0;
    222     if(partsList==NULL) {
    223         partsList=new MessagePatternPartsList();
    224         if(partsList==NULL) {
    225             errorCode=U_MEMORY_ALLOCATION_ERROR;
    226             return FALSE;
    227         }
    228         parts=partsList->a.getAlias();
    229     }
    230     if(other.partsLength>0) {
    231         partsList->copyFrom(*other.partsList, other.partsLength, errorCode);
    232         if(U_FAILURE(errorCode)) {
    233             return FALSE;
    234         }
    235         parts=partsList->a.getAlias();
    236         partsLength=other.partsLength;
    237     }
    238     if(other.numericValuesLength>0) {
    239         if(numericValuesList==NULL) {
    240             numericValuesList=new MessagePatternDoubleList();
    241             if(numericValuesList==NULL) {
    242                 errorCode=U_MEMORY_ALLOCATION_ERROR;
    243                 return FALSE;
    244             }
    245             numericValues=numericValuesList->a.getAlias();
    246         }
    247         numericValuesList->copyFrom(
    248             *other.numericValuesList, other.numericValuesLength, errorCode);
    249         if(U_FAILURE(errorCode)) {
    250             return FALSE;
    251         }
    252         numericValues=numericValuesList->a.getAlias();
    253         numericValuesLength=other.numericValuesLength;
    254     }
    255     return TRUE;
    256 }
    257 
    258 MessagePattern::~MessagePattern() {
    259     delete partsList;
    260     delete numericValuesList;
    261 }
    262 
    263 // MessagePattern API ------------------------------------------------------ ***
    264 
    265 MessagePattern &
    266 MessagePattern::parse(const UnicodeString &pattern, UParseError *parseError, UErrorCode &errorCode) {
    267     preParse(pattern, parseError, errorCode);
    268     parseMessage(0, 0, 0, UMSGPAT_ARG_TYPE_NONE, parseError, errorCode);
    269     postParse();
    270     return *this;
    271 }
    272 
    273 MessagePattern &
    274 MessagePattern::parseChoiceStyle(const UnicodeString &pattern,
    275                                  UParseError *parseError, UErrorCode &errorCode) {
    276     preParse(pattern, parseError, errorCode);
    277     parseChoiceStyle(0, 0, parseError, errorCode);
    278     postParse();
    279     return *this;
    280 }
    281 
    282 MessagePattern &
    283 MessagePattern::parsePluralStyle(const UnicodeString &pattern,
    284                                  UParseError *parseError, UErrorCode &errorCode) {
    285     preParse(pattern, parseError, errorCode);
    286     parsePluralOrSelectStyle(UMSGPAT_ARG_TYPE_PLURAL, 0, 0, parseError, errorCode);
    287     postParse();
    288     return *this;
    289 }
    290 
    291 MessagePattern &
    292 MessagePattern::parseSelectStyle(const UnicodeString &pattern,
    293                                  UParseError *parseError, UErrorCode &errorCode) {
    294     preParse(pattern, parseError, errorCode);
    295     parsePluralOrSelectStyle(UMSGPAT_ARG_TYPE_SELECT, 0, 0, parseError, errorCode);
    296     postParse();
    297     return *this;
    298 }
    299 
    300 void
    301 MessagePattern::clear() {
    302     // Mostly the same as preParse().
    303     msg.remove();
    304     hasArgNames=hasArgNumbers=FALSE;
    305     needsAutoQuoting=FALSE;
    306     partsLength=0;
    307     numericValuesLength=0;
    308 }
    309 
    310 UBool
    311 MessagePattern::operator==(const MessagePattern &other) const {
    312     if(this==&other) {
    313         return TRUE;
    314     }
    315     return
    316         aposMode==other.aposMode &&
    317         msg==other.msg &&
    318         // parts.equals(o.parts)
    319         partsLength==other.partsLength &&
    320         (partsLength==0 || partsList->equals(*other.partsList, partsLength));
    321     // No need to compare numericValues if msg and parts are the same.
    322 }
    323 
    324 int32_t
    325 MessagePattern::hashCode() const {
    326     int32_t hash=(aposMode*37+msg.hashCode())*37+partsLength;
    327     for(int32_t i=0; i<partsLength; ++i) {
    328         hash=hash*37+parts[i].hashCode();
    329     }
    330     return hash;
    331 }
    332 
    333 int32_t
    334 MessagePattern::validateArgumentName(const UnicodeString &name) {
    335     if(!PatternProps::isIdentifier(name.getBuffer(), name.length())) {
    336         return UMSGPAT_ARG_NAME_NOT_VALID;
    337     }
    338     return parseArgNumber(name, 0, name.length());
    339 }
    340 
    341 UnicodeString
    342 MessagePattern::autoQuoteApostropheDeep() const {
    343     if(!needsAutoQuoting) {
    344         return msg;
    345     }
    346     UnicodeString modified(msg);
    347     // Iterate backward so that the insertion indexes do not change.
    348     int32_t count=countParts();
    349     for(int32_t i=count; i>0;) {
    350         const Part &part=getPart(--i);
    351         if(part.getType()==UMSGPAT_PART_TYPE_INSERT_CHAR) {
    352            modified.insert(part.index, (UChar)part.value);
    353         }
    354     }
    355     return modified;
    356 }
    357 
    358 double
    359 MessagePattern::getNumericValue(const Part &part) const {
    360     UMessagePatternPartType type=part.type;
    361     if(type==UMSGPAT_PART_TYPE_ARG_INT) {
    362         return part.value;
    363     } else if(type==UMSGPAT_PART_TYPE_ARG_DOUBLE) {
    364         return numericValues[part.value];
    365     } else {
    366         return UMSGPAT_NO_NUMERIC_VALUE;
    367     }
    368 }
    369 
    370 /**
    371   * Returns the "offset:" value of a PluralFormat argument, or 0 if none is specified.
    372   * @param pluralStart the index of the first PluralFormat argument style part. (0..countParts()-1)
    373   * @return the "offset:" value.
    374   * @draft ICU 4.8
    375   */
    376 double
    377 MessagePattern::getPluralOffset(int32_t pluralStart) const {
    378     const Part &part=getPart(pluralStart);
    379     if(Part::hasNumericValue(part.type)) {
    380         return getNumericValue(part);
    381     } else {
    382         return 0;
    383     }
    384 }
    385 
    386 // MessagePattern::Part ---------------------------------------------------- ***
    387 
    388 UBool
    389 MessagePattern::Part::operator==(const Part &other) const {
    390     if(this==&other) {
    391         return TRUE;
    392     }
    393     return
    394         type==other.type &&
    395         index==other.index &&
    396         length==other.length &&
    397         value==other.value &&
    398         limitPartIndex==other.limitPartIndex;
    399 }
    400 
    401 // MessagePattern parser --------------------------------------------------- ***
    402 
    403 void
    404 MessagePattern::preParse(const UnicodeString &pattern, UParseError *parseError, UErrorCode &errorCode) {
    405     if(U_FAILURE(errorCode)) {
    406         return;
    407     }
    408     if(parseError!=NULL) {
    409         parseError->line=0;
    410         parseError->offset=0;
    411         parseError->preContext[0]=0;
    412         parseError->postContext[0]=0;
    413     }
    414     msg=pattern;
    415     hasArgNames=hasArgNumbers=FALSE;
    416     needsAutoQuoting=FALSE;
    417     partsLength=0;
    418     numericValuesLength=0;
    419 }
    420 
    421 void
    422 MessagePattern::postParse() {
    423     if(partsList!=NULL) {
    424         parts=partsList->a.getAlias();
    425     }
    426     if(numericValuesList!=NULL) {
    427         numericValues=numericValuesList->a.getAlias();
    428     }
    429 }
    430 
    431 int32_t
    432 MessagePattern::parseMessage(int32_t index, int32_t msgStartLength,
    433                              int32_t nestingLevel, UMessagePatternArgType parentType,
    434                              UParseError *parseError, UErrorCode &errorCode) {
    435     if(U_FAILURE(errorCode)) {
    436         return 0;
    437     }
    438     if(nestingLevel>Part::MAX_VALUE) {
    439         errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    440         return 0;
    441     }
    442     int32_t msgStart=partsLength;
    443     addPart(UMSGPAT_PART_TYPE_MSG_START, index, msgStartLength, nestingLevel, errorCode);
    444     index+=msgStartLength;
    445     for(;;) {  // while(index<msg.length()) with U_FAILURE(errorCode) check
    446         if(U_FAILURE(errorCode)) {
    447             return 0;
    448         }
    449         if(index>=msg.length()) {
    450             break;
    451         }
    452         UChar c=msg.charAt(index++);
    453         if(c==u_apos) {
    454             if(index==msg.length()) {
    455                 // The apostrophe is the last character in the pattern.
    456                 // Add a Part for auto-quoting.
    457                 addPart(UMSGPAT_PART_TYPE_INSERT_CHAR, index, 0,
    458                         u_apos, errorCode);  // value=char to be inserted
    459                 needsAutoQuoting=TRUE;
    460             } else {
    461                 c=msg.charAt(index);
    462                 if(c==u_apos) {
    463                     // double apostrophe, skip the second one
    464                     addPart(UMSGPAT_PART_TYPE_SKIP_SYNTAX, index++, 1, 0, errorCode);
    465                 } else if(
    466                     aposMode==UMSGPAT_APOS_DOUBLE_REQUIRED ||
    467                     c==u_leftCurlyBrace || c==u_rightCurlyBrace ||
    468                     (parentType==UMSGPAT_ARG_TYPE_CHOICE && c==u_pipe) ||
    469                     (UMSGPAT_ARG_TYPE_HAS_PLURAL_STYLE(parentType) && c==u_pound)
    470                 ) {
    471                     // skip the quote-starting apostrophe
    472                     addPart(UMSGPAT_PART_TYPE_SKIP_SYNTAX, index-1, 1, 0, errorCode);
    473                     // find the end of the quoted literal text
    474                     for(;;) {
    475                         index=msg.indexOf(u_apos, index+1);
    476                         if(index>=0) {
    477                             if(/*(index+1)<msg.length() &&*/ msg.charAt(index+1)==u_apos) {
    478                                 // double apostrophe inside quoted literal text
    479                                 // still encodes a single apostrophe, skip the second one
    480                                 addPart(UMSGPAT_PART_TYPE_SKIP_SYNTAX, ++index, 1, 0, errorCode);
    481                             } else {
    482                                 // skip the quote-ending apostrophe
    483                                 addPart(UMSGPAT_PART_TYPE_SKIP_SYNTAX, index++, 1, 0, errorCode);
    484                                 break;
    485                             }
    486                         } else {
    487                             // The quoted text reaches to the end of the of the message.
    488                             index=msg.length();
    489                             // Add a Part for auto-quoting.
    490                             addPart(UMSGPAT_PART_TYPE_INSERT_CHAR, index, 0,
    491                                     u_apos, errorCode);  // value=char to be inserted
    492                             needsAutoQuoting=TRUE;
    493                             break;
    494                         }
    495                     }
    496                 } else {
    497                     // Interpret the apostrophe as literal text.
    498                     // Add a Part for auto-quoting.
    499                     addPart(UMSGPAT_PART_TYPE_INSERT_CHAR, index, 0,
    500                             u_apos, errorCode);  // value=char to be inserted
    501                     needsAutoQuoting=TRUE;
    502                 }
    503             }
    504         } else if(UMSGPAT_ARG_TYPE_HAS_PLURAL_STYLE(parentType) && c==u_pound) {
    505             // The unquoted # in a plural message fragment will be replaced
    506             // with the (number-offset).
    507             addPart(UMSGPAT_PART_TYPE_REPLACE_NUMBER, index-1, 1, 0, errorCode);
    508         } else if(c==u_leftCurlyBrace) {
    509             index=parseArg(index-1, 1, nestingLevel, parseError, errorCode);
    510         } else if((nestingLevel>0 && c==u_rightCurlyBrace) ||
    511                   (parentType==UMSGPAT_ARG_TYPE_CHOICE && c==u_pipe)) {
    512             // Finish the message before the terminator.
    513             // In a choice style, report the "}" substring only for the following ARG_LIMIT,
    514             // not for this MSG_LIMIT.
    515             int32_t limitLength=(parentType==UMSGPAT_ARG_TYPE_CHOICE && c==u_rightCurlyBrace) ? 0 : 1;
    516             addLimitPart(msgStart, UMSGPAT_PART_TYPE_MSG_LIMIT, index-1, limitLength,
    517                          nestingLevel, errorCode);
    518             if(parentType==UMSGPAT_ARG_TYPE_CHOICE) {
    519                 // Let the choice style parser see the '}' or '|'.
    520                 return index-1;
    521             } else {
    522                 // continue parsing after the '}'
    523                 return index;
    524             }
    525         }  // else: c is part of literal text
    526     }
    527     if(nestingLevel>0 && !inTopLevelChoiceMessage(nestingLevel, parentType)) {
    528         setParseError(parseError, 0);  // Unmatched '{' braces in message.
    529         errorCode=U_UNMATCHED_BRACES;
    530         return 0;
    531     }
    532     addLimitPart(msgStart, UMSGPAT_PART_TYPE_MSG_LIMIT, index, 0, nestingLevel, errorCode);
    533     return index;
    534 }
    535 
    536 int32_t
    537 MessagePattern::parseArg(int32_t index, int32_t argStartLength, int32_t nestingLevel,
    538                          UParseError *parseError, UErrorCode &errorCode) {
    539     int32_t argStart=partsLength;
    540     UMessagePatternArgType argType=UMSGPAT_ARG_TYPE_NONE;
    541     addPart(UMSGPAT_PART_TYPE_ARG_START, index, argStartLength, argType, errorCode);
    542     if(U_FAILURE(errorCode)) {
    543         return 0;
    544     }
    545     int32_t nameIndex=index=skipWhiteSpace(index+argStartLength);
    546     if(index==msg.length()) {
    547         setParseError(parseError, 0);  // Unmatched '{' braces in message.
    548         errorCode=U_UNMATCHED_BRACES;
    549         return 0;
    550     }
    551     // parse argument name or number
    552     index=skipIdentifier(index);
    553     int32_t number=parseArgNumber(nameIndex, index);
    554     if(number>=0) {
    555         int32_t length=index-nameIndex;
    556         if(length>Part::MAX_LENGTH || number>Part::MAX_VALUE) {
    557             setParseError(parseError, nameIndex);  // Argument number too large.
    558             errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    559             return 0;
    560         }
    561         hasArgNumbers=TRUE;
    562         addPart(UMSGPAT_PART_TYPE_ARG_NUMBER, nameIndex, length, number, errorCode);
    563     } else if(number==UMSGPAT_ARG_NAME_NOT_NUMBER) {
    564         int32_t length=index-nameIndex;
    565         if(length>Part::MAX_LENGTH) {
    566             setParseError(parseError, nameIndex);  // Argument name too long.
    567             errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    568             return 0;
    569         }
    570         hasArgNames=TRUE;
    571         addPart(UMSGPAT_PART_TYPE_ARG_NAME, nameIndex, length, 0, errorCode);
    572     } else {  // number<-1 (ARG_NAME_NOT_VALID)
    573         setParseError(parseError, nameIndex);  // Bad argument syntax.
    574         errorCode=U_PATTERN_SYNTAX_ERROR;
    575         return 0;
    576     }
    577     index=skipWhiteSpace(index);
    578     if(index==msg.length()) {
    579         setParseError(parseError, 0);  // Unmatched '{' braces in message.
    580         errorCode=U_UNMATCHED_BRACES;
    581         return 0;
    582     }
    583     UChar c=msg.charAt(index);
    584     if(c==u_rightCurlyBrace) {
    585         // all done
    586     } else if(c!=u_comma) {
    587         setParseError(parseError, nameIndex);  // Bad argument syntax.
    588         errorCode=U_PATTERN_SYNTAX_ERROR;
    589         return 0;
    590     } else /* ',' */ {
    591         // parse argument type: case-sensitive a-zA-Z
    592         int32_t typeIndex=index=skipWhiteSpace(index+1);
    593         while(index<msg.length() && isArgTypeChar(msg.charAt(index))) {
    594             ++index;
    595         }
    596         int32_t length=index-typeIndex;
    597         index=skipWhiteSpace(index);
    598         if(index==msg.length()) {
    599             setParseError(parseError, 0);  // Unmatched '{' braces in message.
    600             errorCode=U_UNMATCHED_BRACES;
    601             return 0;
    602         }
    603         if(length==0 || ((c=msg.charAt(index))!=u_comma && c!=u_rightCurlyBrace)) {
    604             setParseError(parseError, nameIndex);  // Bad argument syntax.
    605             errorCode=U_PATTERN_SYNTAX_ERROR;
    606             return 0;
    607         }
    608         if(length>Part::MAX_LENGTH) {
    609             setParseError(parseError, nameIndex);  // Argument type name too long.
    610             errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    611             return 0;
    612         }
    613         argType=UMSGPAT_ARG_TYPE_SIMPLE;
    614         if(length==6) {
    615             // case-insensitive comparisons for complex-type names
    616             if(isChoice(typeIndex)) {
    617                 argType=UMSGPAT_ARG_TYPE_CHOICE;
    618             } else if(isPlural(typeIndex)) {
    619                 argType=UMSGPAT_ARG_TYPE_PLURAL;
    620             } else if(isSelect(typeIndex)) {
    621                 argType=UMSGPAT_ARG_TYPE_SELECT;
    622             }
    623         } else if(length==13) {
    624             if(isSelect(typeIndex) && isOrdinal(typeIndex+6)) {
    625                 argType=UMSGPAT_ARG_TYPE_SELECTORDINAL;
    626             }
    627         }
    628         // change the ARG_START type from NONE to argType
    629         partsList->a[argStart].value=(int16_t)argType;
    630         if(argType==UMSGPAT_ARG_TYPE_SIMPLE) {
    631             addPart(UMSGPAT_PART_TYPE_ARG_TYPE, typeIndex, length, 0, errorCode);
    632         }
    633         // look for an argument style (pattern)
    634         if(c==u_rightCurlyBrace) {
    635             if(argType!=UMSGPAT_ARG_TYPE_SIMPLE) {
    636                 setParseError(parseError, nameIndex);  // No style field for complex argument.
    637                 errorCode=U_PATTERN_SYNTAX_ERROR;
    638                 return 0;
    639             }
    640         } else /* ',' */ {
    641             ++index;
    642             if(argType==UMSGPAT_ARG_TYPE_SIMPLE) {
    643                 index=parseSimpleStyle(index, parseError, errorCode);
    644             } else if(argType==UMSGPAT_ARG_TYPE_CHOICE) {
    645                 index=parseChoiceStyle(index, nestingLevel, parseError, errorCode);
    646             } else {
    647                 index=parsePluralOrSelectStyle(argType, index, nestingLevel, parseError, errorCode);
    648             }
    649         }
    650     }
    651     // Argument parsing stopped on the '}'.
    652     addLimitPart(argStart, UMSGPAT_PART_TYPE_ARG_LIMIT, index, 1, argType, errorCode);
    653     return index+1;
    654 }
    655 
    656 int32_t
    657 MessagePattern::parseSimpleStyle(int32_t index, UParseError *parseError, UErrorCode &errorCode) {
    658     if(U_FAILURE(errorCode)) {
    659         return 0;
    660     }
    661     int32_t start=index;
    662     int32_t nestedBraces=0;
    663     while(index<msg.length()) {
    664         UChar c=msg.charAt(index++);
    665         if(c==u_apos) {
    666             // Treat apostrophe as quoting but include it in the style part.
    667             // Find the end of the quoted literal text.
    668             index=msg.indexOf(u_apos, index);
    669             if(index<0) {
    670                 // Quoted literal argument style text reaches to the end of the message.
    671                 setParseError(parseError, start);
    672                 errorCode=U_PATTERN_SYNTAX_ERROR;
    673                 return 0;
    674             }
    675             // skip the quote-ending apostrophe
    676             ++index;
    677         } else if(c==u_leftCurlyBrace) {
    678             ++nestedBraces;
    679         } else if(c==u_rightCurlyBrace) {
    680             if(nestedBraces>0) {
    681                 --nestedBraces;
    682             } else {
    683                 int32_t length=--index-start;
    684                 if(length>Part::MAX_LENGTH) {
    685                     setParseError(parseError, start);  // Argument style text too long.
    686                     errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    687                     return 0;
    688                 }
    689                 addPart(UMSGPAT_PART_TYPE_ARG_STYLE, start, length, 0, errorCode);
    690                 return index;
    691             }
    692         }  // c is part of literal text
    693     }
    694     setParseError(parseError, 0);  // Unmatched '{' braces in message.
    695     errorCode=U_UNMATCHED_BRACES;
    696     return 0;
    697 }
    698 
    699 int32_t
    700 MessagePattern::parseChoiceStyle(int32_t index, int32_t nestingLevel,
    701                                  UParseError *parseError, UErrorCode &errorCode) {
    702     if(U_FAILURE(errorCode)) {
    703         return 0;
    704     }
    705     int32_t start=index;
    706     index=skipWhiteSpace(index);
    707     if(index==msg.length() || msg.charAt(index)==u_rightCurlyBrace) {
    708         setParseError(parseError, 0);  // Missing choice argument pattern.
    709         errorCode=U_PATTERN_SYNTAX_ERROR;
    710         return 0;
    711     }
    712     for(;;) {
    713         // The choice argument style contains |-separated (number, separator, message) triples.
    714         // Parse the number.
    715         int32_t numberIndex=index;
    716         index=skipDouble(index);
    717         int32_t length=index-numberIndex;
    718         if(length==0) {
    719             setParseError(parseError, start);  // Bad choice pattern syntax.
    720             errorCode=U_PATTERN_SYNTAX_ERROR;
    721             return 0;
    722         }
    723         if(length>Part::MAX_LENGTH) {
    724             setParseError(parseError, numberIndex);  // Choice number too long.
    725             errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    726             return 0;
    727         }
    728         parseDouble(numberIndex, index, TRUE, parseError, errorCode);  // adds ARG_INT or ARG_DOUBLE
    729         if(U_FAILURE(errorCode)) {
    730             return 0;
    731         }
    732         // Parse the separator.
    733         index=skipWhiteSpace(index);
    734         if(index==msg.length()) {
    735             setParseError(parseError, start);  // Bad choice pattern syntax.
    736             errorCode=U_PATTERN_SYNTAX_ERROR;
    737             return 0;
    738         }
    739         UChar c=msg.charAt(index);
    740         if(!(c==u_pound || c==u_lessThan || c==u_lessOrEqual)) {  // U+2264 is <=
    741             setParseError(parseError, start);  // Expected choice separator (#<\u2264) instead of c.
    742             errorCode=U_PATTERN_SYNTAX_ERROR;
    743             return 0;
    744         }
    745         addPart(UMSGPAT_PART_TYPE_ARG_SELECTOR, index, 1, 0, errorCode);
    746         // Parse the message fragment.
    747         index=parseMessage(++index, 0, nestingLevel+1, UMSGPAT_ARG_TYPE_CHOICE, parseError, errorCode);
    748         if(U_FAILURE(errorCode)) {
    749             return 0;
    750         }
    751         // parseMessage(..., CHOICE) returns the index of the terminator, or msg.length().
    752         if(index==msg.length()) {
    753             return index;
    754         }
    755         if(msg.charAt(index)==u_rightCurlyBrace) {
    756             if(!inMessageFormatPattern(nestingLevel)) {
    757                 setParseError(parseError, start);  // Bad choice pattern syntax.
    758                 errorCode=U_PATTERN_SYNTAX_ERROR;
    759                 return 0;
    760             }
    761             return index;
    762         }  // else the terminator is '|'
    763         index=skipWhiteSpace(index+1);
    764     }
    765 }
    766 
    767 int32_t
    768 MessagePattern::parsePluralOrSelectStyle(UMessagePatternArgType argType,
    769                                          int32_t index, int32_t nestingLevel,
    770                                          UParseError *parseError, UErrorCode &errorCode) {
    771     if(U_FAILURE(errorCode)) {
    772         return 0;
    773     }
    774     int32_t start=index;
    775     UBool isEmpty=TRUE;
    776     UBool hasOther=FALSE;
    777     for(;;) {
    778         // First, collect the selector looking for a small set of terminators.
    779         // It would be a little faster to consider the syntax of each possible
    780         // token right here, but that makes the code too complicated.
    781         index=skipWhiteSpace(index);
    782         UBool eos=index==msg.length();
    783         if(eos || msg.charAt(index)==u_rightCurlyBrace) {
    784             if(eos==inMessageFormatPattern(nestingLevel)) {
    785                 setParseError(parseError, start);  // Bad plural/select pattern syntax.
    786                 errorCode=U_PATTERN_SYNTAX_ERROR;
    787                 return 0;
    788             }
    789             if(!hasOther) {
    790                 setParseError(parseError, 0);  // Missing 'other' keyword in plural/select pattern.
    791                 errorCode=U_DEFAULT_KEYWORD_MISSING;
    792                 return 0;
    793             }
    794             return index;
    795         }
    796         int32_t selectorIndex=index;
    797         if(UMSGPAT_ARG_TYPE_HAS_PLURAL_STYLE(argType) && msg.charAt(selectorIndex)==u_equal) {
    798             // explicit-value plural selector: =double
    799             index=skipDouble(index+1);
    800             int32_t length=index-selectorIndex;
    801             if(length==1) {
    802                 setParseError(parseError, start);  // Bad plural/select pattern syntax.
    803                 errorCode=U_PATTERN_SYNTAX_ERROR;
    804                 return 0;
    805             }
    806             if(length>Part::MAX_LENGTH) {
    807                 setParseError(parseError, selectorIndex);  // Argument selector too long.
    808                 errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    809                 return 0;
    810             }
    811             addPart(UMSGPAT_PART_TYPE_ARG_SELECTOR, selectorIndex, length, 0, errorCode);
    812             parseDouble(selectorIndex+1, index, FALSE,
    813                         parseError, errorCode);  // adds ARG_INT or ARG_DOUBLE
    814         } else {
    815             index=skipIdentifier(index);
    816             int32_t length=index-selectorIndex;
    817             if(length==0) {
    818                 setParseError(parseError, start);  // Bad plural/select pattern syntax.
    819                 errorCode=U_PATTERN_SYNTAX_ERROR;
    820                 return 0;
    821             }
    822             // Note: The ':' in "offset:" is just beyond the skipIdentifier() range.
    823             if( UMSGPAT_ARG_TYPE_HAS_PLURAL_STYLE(argType) && length==6 && index<msg.length() &&
    824                 0==msg.compare(selectorIndex, 7, kOffsetColon, 0, 7)
    825             ) {
    826                 // plural offset, not a selector
    827                 if(!isEmpty) {
    828                     // Plural argument 'offset:' (if present) must precede key-message pairs.
    829                     setParseError(parseError, start);
    830                     errorCode=U_PATTERN_SYNTAX_ERROR;
    831                     return 0;
    832                 }
    833                 // allow whitespace between offset: and its value
    834                 int32_t valueIndex=skipWhiteSpace(index+1);  // The ':' is at index.
    835                 index=skipDouble(valueIndex);
    836                 if(index==valueIndex) {
    837                     setParseError(parseError, start);  // Missing value for plural 'offset:'.
    838                     errorCode=U_PATTERN_SYNTAX_ERROR;
    839                     return 0;
    840                 }
    841                 if((index-valueIndex)>Part::MAX_LENGTH) {
    842                     setParseError(parseError, valueIndex);  // Plural offset value too long.
    843                     errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    844                     return 0;
    845                 }
    846                 parseDouble(valueIndex, index, FALSE,
    847                             parseError, errorCode);  // adds ARG_INT or ARG_DOUBLE
    848                 if(U_FAILURE(errorCode)) {
    849                     return 0;
    850                 }
    851                 isEmpty=FALSE;
    852                 continue;  // no message fragment after the offset
    853             } else {
    854                 // normal selector word
    855                 if(length>Part::MAX_LENGTH) {
    856                     setParseError(parseError, selectorIndex);  // Argument selector too long.
    857                     errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
    858                     return 0;
    859                 }
    860                 addPart(UMSGPAT_PART_TYPE_ARG_SELECTOR, selectorIndex, length, 0, errorCode);
    861                 if(0==msg.compare(selectorIndex, length, kOther, 0, 5)) {
    862                     hasOther=TRUE;
    863                 }
    864             }
    865         }
    866         if(U_FAILURE(errorCode)) {
    867             return 0;
    868         }
    869 
    870         // parse the message fragment following the selector
    871         index=skipWhiteSpace(index);
    872         if(index==msg.length() || msg.charAt(index)!=u_leftCurlyBrace) {
    873             setParseError(parseError, selectorIndex);  // No message fragment after plural/select selector.
    874             errorCode=U_PATTERN_SYNTAX_ERROR;
    875             return 0;
    876         }
    877         index=parseMessage(index, 1, nestingLevel+1, argType, parseError, errorCode);
    878         if(U_FAILURE(errorCode)) {
    879             return 0;
    880         }
    881         isEmpty=FALSE;
    882     }
    883 }
    884 
    885 int32_t
    886 MessagePattern::parseArgNumber(const UnicodeString &s, int32_t start, int32_t limit) {
    887     // If the identifier contains only ASCII digits, then it is an argument _number_
    888     // and must not have leading zeros (except "0" itself).
    889     // Otherwise it is an argument _name_.
    890     if(start>=limit) {
    891         return UMSGPAT_ARG_NAME_NOT_VALID;
    892     }
    893     int32_t number;
    894     // Defer numeric errors until we know there are only digits.
    895     UBool badNumber;
    896     UChar c=s.charAt(start++);
    897     if(c==0x30) {
    898         if(start==limit) {
    899             return 0;
    900         } else {
    901             number=0;
    902             badNumber=TRUE;  // leading zero
    903         }
    904     } else if(0x31<=c && c<=0x39) {
    905         number=c-0x30;
    906         badNumber=FALSE;
    907     } else {
    908         return UMSGPAT_ARG_NAME_NOT_NUMBER;
    909     }
    910     while(start<limit) {
    911         c=s.charAt(start++);
    912         if(0x30<=c && c<=0x39) {
    913             if(number>=INT32_MAX/10) {
    914                 badNumber=TRUE;  // overflow
    915             }
    916             number=number*10+(c-0x30);
    917         } else {
    918             return UMSGPAT_ARG_NAME_NOT_NUMBER;
    919         }
    920     }
    921     // There are only ASCII digits.
    922     if(badNumber) {
    923         return UMSGPAT_ARG_NAME_NOT_VALID;
    924     } else {
    925         return number;
    926     }
    927 }
    928 
    929 void
    930 MessagePattern::parseDouble(int32_t start, int32_t limit, UBool allowInfinity,
    931                             UParseError *parseError, UErrorCode &errorCode) {
    932     if(U_FAILURE(errorCode)) {
    933         return;
    934     }
    935     U_ASSERT(start<limit);
    936     // fake loop for easy exit and single throw statement
    937     for(;;) { /*loop doesn't iterate*/
    938         // fast path for small integers and infinity
    939         int32_t value=0;
    940         int32_t isNegative=0;  // not boolean so that we can easily add it to value
    941         int32_t index=start;
    942         UChar c=msg.charAt(index++);
    943         if(c==u_minus) {
    944             isNegative=1;
    945             if(index==limit) {
    946                 break;  // no number
    947             }
    948             c=msg.charAt(index++);
    949         } else if(c==u_plus) {
    950             if(index==limit) {
    951                 break;  // no number
    952             }
    953             c=msg.charAt(index++);
    954         }
    955         if(c==0x221e) {  // infinity
    956             if(allowInfinity && index==limit) {
    957                 double infinity=uprv_getInfinity();
    958                 addArgDoublePart(
    959                     isNegative!=0 ? -infinity : infinity,
    960                     start, limit-start, errorCode);
    961                 return;
    962             } else {
    963                 break;
    964             }
    965         }
    966         // try to parse the number as a small integer but fall back to a double
    967         while('0'<=c && c<='9') {
    968             value=value*10+(c-'0');
    969             if(value>(Part::MAX_VALUE+isNegative)) {
    970                 break;  // not a small-enough integer
    971             }
    972             if(index==limit) {
    973                 addPart(UMSGPAT_PART_TYPE_ARG_INT, start, limit-start,
    974                         isNegative!=0 ? -value : value, errorCode);
    975                 return;
    976             }
    977             c=msg.charAt(index++);
    978         }
    979         // Let Double.parseDouble() throw a NumberFormatException.
    980         char numberChars[128];
    981         int32_t capacity=(int32_t)sizeof(numberChars);
    982         int32_t length=limit-start;
    983         if(length>=capacity) {
    984             break;  // number too long
    985         }
    986         msg.extract(start, length, numberChars, capacity, US_INV);
    987         if((int32_t)uprv_strlen(numberChars)<length) {
    988             break;  // contains non-invariant character that was turned into NUL
    989         }
    990         char *end;
    991         double numericValue=uprv_strtod(numberChars, &end);
    992         if(end!=(numberChars+length)) {
    993             break;  // parsing error
    994         }
    995         addArgDoublePart(numericValue, start, length, errorCode);
    996         return;
    997     }
    998     setParseError(parseError, start /*, limit*/);  // Bad syntax for numeric value.
    999     errorCode=U_PATTERN_SYNTAX_ERROR;
   1000     return;
   1001 }
   1002 
   1003 int32_t
   1004 MessagePattern::skipWhiteSpace(int32_t index) {
   1005     const UChar *s=msg.getBuffer();
   1006     int32_t msgLength=msg.length();
   1007     const UChar *t=PatternProps::skipWhiteSpace(s+index, msgLength-index);
   1008     return (int32_t)(t-s);
   1009 }
   1010 
   1011 int32_t
   1012 MessagePattern::skipIdentifier(int32_t index) {
   1013     const UChar *s=msg.getBuffer();
   1014     int32_t msgLength=msg.length();
   1015     const UChar *t=PatternProps::skipIdentifier(s+index, msgLength-index);
   1016     return (int32_t)(t-s);
   1017 }
   1018 
   1019 int32_t
   1020 MessagePattern::skipDouble(int32_t index) {
   1021     int32_t msgLength=msg.length();
   1022     while(index<msgLength) {
   1023         UChar c=msg.charAt(index);
   1024         // U+221E: Allow the infinity symbol, for ChoiceFormat patterns.
   1025         if((c<0x30 && c!=u_plus && c!=u_minus && c!=u_dot) || (c>0x39 && c!=u_e && c!=u_E && c!=0x221e)) {
   1026             break;
   1027         }
   1028         ++index;
   1029     }
   1030     return index;
   1031 }
   1032 
   1033 UBool
   1034 MessagePattern::isArgTypeChar(UChar32 c) {
   1035     return (u_a<=c && c<=u_z) || (u_A<=c && c<=u_Z);
   1036 }
   1037 
   1038 UBool
   1039 MessagePattern::isChoice(int32_t index) {
   1040     UChar c;
   1041     return
   1042         ((c=msg.charAt(index++))==u_c || c==u_C) &&
   1043         ((c=msg.charAt(index++))==u_h || c==u_H) &&
   1044         ((c=msg.charAt(index++))==u_o || c==u_O) &&
   1045         ((c=msg.charAt(index++))==u_i || c==u_I) &&
   1046         ((c=msg.charAt(index++))==u_c || c==u_C) &&
   1047         ((c=msg.charAt(index))==u_e || c==u_E);
   1048 }
   1049 
   1050 UBool
   1051 MessagePattern::isPlural(int32_t index) {
   1052     UChar c;
   1053     return
   1054         ((c=msg.charAt(index++))==u_p || c==u_P) &&
   1055         ((c=msg.charAt(index++))==u_l || c==u_L) &&
   1056         ((c=msg.charAt(index++))==u_u || c==u_U) &&
   1057         ((c=msg.charAt(index++))==u_r || c==u_R) &&
   1058         ((c=msg.charAt(index++))==u_a || c==u_A) &&
   1059         ((c=msg.charAt(index))==u_l || c==u_L);
   1060 }
   1061 
   1062 UBool
   1063 MessagePattern::isSelect(int32_t index) {
   1064     UChar c;
   1065     return
   1066         ((c=msg.charAt(index++))==u_s || c==u_S) &&
   1067         ((c=msg.charAt(index++))==u_e || c==u_E) &&
   1068         ((c=msg.charAt(index++))==u_l || c==u_L) &&
   1069         ((c=msg.charAt(index++))==u_e || c==u_E) &&
   1070         ((c=msg.charAt(index++))==u_c || c==u_C) &&
   1071         ((c=msg.charAt(index))==u_t || c==u_T);
   1072 }
   1073 
   1074 UBool
   1075 MessagePattern::isOrdinal(int32_t index) {
   1076     UChar c;
   1077     return
   1078         ((c=msg.charAt(index++))==u_o || c==u_O) &&
   1079         ((c=msg.charAt(index++))==u_r || c==u_R) &&
   1080         ((c=msg.charAt(index++))==u_d || c==u_D) &&
   1081         ((c=msg.charAt(index++))==u_i || c==u_I) &&
   1082         ((c=msg.charAt(index++))==u_n || c==u_N) &&
   1083         ((c=msg.charAt(index++))==u_a || c==u_A) &&
   1084         ((c=msg.charAt(index))==u_l || c==u_L);
   1085 }
   1086 
   1087 UBool
   1088 MessagePattern::inMessageFormatPattern(int32_t nestingLevel) {
   1089     return nestingLevel>0 || partsList->a[0].type==UMSGPAT_PART_TYPE_MSG_START;
   1090 }
   1091 
   1092 UBool
   1093 MessagePattern::inTopLevelChoiceMessage(int32_t nestingLevel, UMessagePatternArgType parentType) {
   1094     return
   1095         nestingLevel==1 &&
   1096         parentType==UMSGPAT_ARG_TYPE_CHOICE &&
   1097         partsList->a[0].type!=UMSGPAT_PART_TYPE_MSG_START;
   1098 }
   1099 
   1100 void
   1101 MessagePattern::addPart(UMessagePatternPartType type, int32_t index, int32_t length,
   1102                         int32_t value, UErrorCode &errorCode) {
   1103     if(partsList->ensureCapacityForOneMore(partsLength, errorCode)) {
   1104         Part &part=partsList->a[partsLength++];
   1105         part.type=type;
   1106         part.index=index;
   1107         part.length=(uint16_t)length;
   1108         part.value=(int16_t)value;
   1109         part.limitPartIndex=0;
   1110     }
   1111 }
   1112 
   1113 void
   1114 MessagePattern::addLimitPart(int32_t start,
   1115                              UMessagePatternPartType type, int32_t index, int32_t length,
   1116                              int32_t value, UErrorCode &errorCode) {
   1117     partsList->a[start].limitPartIndex=partsLength;
   1118     addPart(type, index, length, value, errorCode);
   1119 }
   1120 
   1121 void
   1122 MessagePattern::addArgDoublePart(double numericValue, int32_t start, int32_t length,
   1123                                  UErrorCode &errorCode) {
   1124     if(U_FAILURE(errorCode)) {
   1125         return;
   1126     }
   1127     int32_t numericIndex=numericValuesLength;
   1128     if(numericValuesList==NULL) {
   1129         numericValuesList=new MessagePatternDoubleList();
   1130         if(numericValuesList==NULL) {
   1131             errorCode=U_MEMORY_ALLOCATION_ERROR;
   1132             return;
   1133         }
   1134     } else if(!numericValuesList->ensureCapacityForOneMore(numericValuesLength, errorCode)) {
   1135         return;
   1136     } else {
   1137         if(numericIndex>Part::MAX_VALUE) {
   1138             errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
   1139             return;
   1140         }
   1141     }
   1142     numericValuesList->a[numericValuesLength++]=numericValue;
   1143     addPart(UMSGPAT_PART_TYPE_ARG_DOUBLE, start, length, numericIndex, errorCode);
   1144 }
   1145 
   1146 void
   1147 MessagePattern::setParseError(UParseError *parseError, int32_t index) {
   1148     if(parseError==NULL) {
   1149         return;
   1150     }
   1151     parseError->offset=index;
   1152 
   1153     // Set preContext to some of msg before index.
   1154     // Avoid splitting a surrogate pair.
   1155     int32_t length=index;
   1156     if(length>=U_PARSE_CONTEXT_LEN) {
   1157         length=U_PARSE_CONTEXT_LEN-1;
   1158         if(length>0 && U16_IS_TRAIL(msg[index-length])) {
   1159             --length;
   1160         }
   1161     }
   1162     msg.extract(index-length, length, parseError->preContext);
   1163     parseError->preContext[length]=0;
   1164 
   1165     // Set postContext to some of msg starting at index.
   1166     length=msg.length()-index;
   1167     if(length>=U_PARSE_CONTEXT_LEN) {
   1168         length=U_PARSE_CONTEXT_LEN-1;
   1169         if(length>0 && U16_IS_LEAD(msg[index+length-1])) {
   1170             --length;
   1171         }
   1172     }
   1173     msg.extract(index, length, parseError->postContext);
   1174     parseError->postContext[length]=0;
   1175 }
   1176 
   1177 // MessageImpl ------------------------------------------------------------- ***
   1178 
   1179 void
   1180 MessageImpl::appendReducedApostrophes(const UnicodeString &s, int32_t start, int32_t limit,
   1181                                       UnicodeString &sb) {
   1182     int32_t doubleApos=-1;
   1183     for(;;) {
   1184         int32_t i=s.indexOf(u_apos, start);
   1185         if(i<0 || i>=limit) {
   1186             sb.append(s, start, limit-start);
   1187             break;
   1188         }
   1189         if(i==doubleApos) {
   1190             // Double apostrophe at start-1 and start==i, append one.
   1191             sb.append(u_apos);
   1192             ++start;
   1193             doubleApos=-1;
   1194         } else {
   1195             // Append text between apostrophes and skip this one.
   1196             sb.append(s, start, i-start);
   1197             doubleApos=start=i+1;
   1198         }
   1199     }
   1200 }
   1201 
   1202 // Ported from second half of ICU4J SelectFormat.format(String).
   1203 UnicodeString &
   1204 MessageImpl::appendSubMessageWithoutSkipSyntax(const MessagePattern &msgPattern,
   1205                                                int32_t msgStart,
   1206                                                UnicodeString &result) {
   1207     const UnicodeString &msgString=msgPattern.getPatternString();
   1208     int32_t prevIndex=msgPattern.getPart(msgStart).getLimit();
   1209     for(int32_t i=msgStart;;) {
   1210         const MessagePattern::Part &part=msgPattern.getPart(++i);
   1211         UMessagePatternPartType type=part.getType();
   1212         int32_t index=part.getIndex();
   1213         if(type==UMSGPAT_PART_TYPE_MSG_LIMIT) {
   1214             return result.append(msgString, prevIndex, index-prevIndex);
   1215         } else if(type==UMSGPAT_PART_TYPE_SKIP_SYNTAX) {
   1216             result.append(msgString, prevIndex, index-prevIndex);
   1217             prevIndex=part.getLimit();
   1218         } else if(type==UMSGPAT_PART_TYPE_ARG_START) {
   1219             result.append(msgString, prevIndex, index-prevIndex);
   1220             prevIndex=index;
   1221             i=msgPattern.getLimitPartIndex(i);
   1222             index=msgPattern.getPart(i).getLimit();
   1223             appendReducedApostrophes(msgString, prevIndex, index, result);
   1224             prevIndex=index;
   1225         }
   1226     }
   1227 }
   1228 
   1229 U_NAMESPACE_END
   1230 
   1231 #endif  // !UCONFIG_NO_FORMATTING
   1232