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      1 //  2016 and later: Unicode, Inc. and others.
      2 // License & terms of use: http://www.unicode.org/copyright.html
      3 /*
      4 *******************************************************************************
      5 *   Copyright (C) 2011, International Business Machines
      6 *   Corporation and others.  All Rights Reserved.
      7 *******************************************************************************
      8 *   file name:  patternprops.cpp
      9 *   encoding:   UTF-8
     10 *   tab size:   8 (not used)
     11 *   indentation:4
     12 *
     13 *   created on: 2011mar13
     14 *   created by: Markus W. Scherer
     15 */
     16 
     17 #include "unicode/utypes.h"
     18 #include "patternprops.h"
     19 
     20 U_NAMESPACE_BEGIN
     21 
     22 /*
     23  * One byte per Latin-1 character.
     24  * Bit 0 is set if either Pattern property is true,
     25  * bit 1 if Pattern_Syntax is true,
     26  * bit 2 if Pattern_White_Space is true.
     27  * That is, Pattern_Syntax is encoded as 3 and Pattern_White_Space as 5.
     28  */
     29 static const uint8_t latin1[256]={
     30     // WS: 9..D
     31     0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 5, 5, 5, 5, 0, 0,
     32     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     33     // WS: 20  Syntax: 21..2F
     34     5, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
     35     // Syntax: 3A..40
     36     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 3, 3,
     37     3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     38     // Syntax: 5B..5E
     39     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 0,
     40     // Syntax: 60
     41     3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     42     // Syntax: 7B..7E
     43     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 0,
     44     // WS: 85
     45     0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     46     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     47     // Syntax: A1..A7, A9, AB, AC, AE
     48     0, 3, 3, 3, 3, 3, 3, 3, 0, 3, 0, 3, 3, 0, 3, 0,
     49     // Syntax: B0, B1, B6, BB, BF
     50     3, 3, 0, 0, 0, 0, 3, 0, 0, 0, 0, 3, 0, 0, 0, 3,
     51     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     52     // Syntax: D7
     53     0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0,
     54     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     55     // Syntax: F7
     56     0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0
     57 };
     58 
     59 /*
     60  * One byte per 32 characters from U+2000..U+303F indexing into
     61  * a small table of 32-bit data words.
     62  * The first two data words are all-zeros and all-ones.
     63  */
     64 static const uint8_t index2000[130]={
     65     2, 3, 4, 0, 0, 0, 0, 0,  // 20xx
     66     0, 0, 0, 0, 5, 1, 1, 1,  // 21xx
     67     1, 1, 1, 1, 1, 1, 1, 1,  // 22xx
     68     1, 1, 1, 1, 1, 1, 1, 1,  // 23xx
     69     1, 1, 1, 0, 0, 0, 0, 0,  // 24xx
     70     1, 1, 1, 1, 1, 1, 1, 1,  // 25xx
     71     1, 1, 1, 1, 1, 1, 1, 1,  // 26xx
     72     1, 1, 1, 6, 7, 1, 1, 1,  // 27xx
     73     1, 1, 1, 1, 1, 1, 1, 1,  // 28xx
     74     1, 1, 1, 1, 1, 1, 1, 1,  // 29xx
     75     1, 1, 1, 1, 1, 1, 1, 1,  // 2Axx
     76     1, 1, 1, 1, 1, 1, 1, 1,  // 2Bxx
     77     0, 0, 0, 0, 0, 0, 0, 0,  // 2Cxx
     78     0, 0, 0, 0, 0, 0, 0, 0,  // 2Dxx
     79     1, 1, 1, 1, 0, 0, 0, 0,  // 2Exx
     80     0, 0, 0, 0, 0, 0, 0, 0,  // 2Fxx
     81     8, 9  // 3000..303F
     82 };
     83 
     84 /*
     85  * One 32-bit integer per 32 characters. Ranges of all-false and all-true
     86  * are mapped to the first two values, other ranges map to appropriate bit patterns.
     87  */
     88 static const uint32_t syntax2000[]={
     89     0,
     90     0xffffffff,
     91     0xffff0000,  // 2: 2010..201F
     92     0x7fff00ff,  // 3: 2020..2027, 2030..203E
     93     0x7feffffe,  // 4: 2041..2053, 2055..205E
     94     0xffff0000,  // 5: 2190..219F
     95     0x003fffff,  // 6: 2760..2775
     96     0xfff00000,  // 7: 2794..279F
     97     0xffffff0e,  // 8: 3001..3003, 3008..301F
     98     0x00010001   // 9: 3020, 3030
     99 };
    100 
    101 /*
    102  * Same as syntax2000, but with additional bits set for the
    103  * Pattern_White_Space characters 200E 200F 2028 2029.
    104  */
    105 static const uint32_t syntaxOrWhiteSpace2000[]={
    106     0,
    107     0xffffffff,
    108     0xffffc000,  // 2: 200E..201F
    109     0x7fff03ff,  // 3: 2020..2029, 2030..203E
    110     0x7feffffe,  // 4: 2041..2053, 2055..205E
    111     0xffff0000,  // 5: 2190..219F
    112     0x003fffff,  // 6: 2760..2775
    113     0xfff00000,  // 7: 2794..279F
    114     0xffffff0e,  // 8: 3001..3003, 3008..301F
    115     0x00010001   // 9: 3020, 3030
    116 };
    117 
    118 UBool
    119 PatternProps::isSyntax(UChar32 c) {
    120     if(c<0) {
    121         return FALSE;
    122     } else if(c<=0xff) {
    123         return (UBool)(latin1[c]>>1)&1;
    124     } else if(c<0x2010) {
    125         return FALSE;
    126     } else if(c<=0x3030) {
    127         uint32_t bits=syntax2000[index2000[(c-0x2000)>>5]];
    128         return (UBool)((bits>>(c&0x1f))&1);
    129     } else if(0xfd3e<=c && c<=0xfe46) {
    130         return c<=0xfd3f || 0xfe45<=c;
    131     } else {
    132         return FALSE;
    133     }
    134 }
    135 
    136 UBool
    137 PatternProps::isSyntaxOrWhiteSpace(UChar32 c) {
    138     if(c<0) {
    139         return FALSE;
    140     } else if(c<=0xff) {
    141         return (UBool)(latin1[c]&1);
    142     } else if(c<0x200e) {
    143         return FALSE;
    144     } else if(c<=0x3030) {
    145         uint32_t bits=syntaxOrWhiteSpace2000[index2000[(c-0x2000)>>5]];
    146         return (UBool)((bits>>(c&0x1f))&1);
    147     } else if(0xfd3e<=c && c<=0xfe46) {
    148         return c<=0xfd3f || 0xfe45<=c;
    149     } else {
    150         return FALSE;
    151     }
    152 }
    153 
    154 UBool
    155 PatternProps::isWhiteSpace(UChar32 c) {
    156     if(c<0) {
    157         return FALSE;
    158     } else if(c<=0xff) {
    159         return (UBool)(latin1[c]>>2)&1;
    160     } else if(0x200e<=c && c<=0x2029) {
    161         return c<=0x200f || 0x2028<=c;
    162     } else {
    163         return FALSE;
    164     }
    165 }
    166 
    167 const UChar *
    168 PatternProps::skipWhiteSpace(const UChar *s, int32_t length) {
    169     while(length>0 && isWhiteSpace(*s)) {
    170         ++s;
    171         --length;
    172     }
    173     return s;
    174 }
    175 
    176 const UChar *
    177 PatternProps::trimWhiteSpace(const UChar *s, int32_t &length) {
    178     if(length<=0 || (!isWhiteSpace(s[0]) && !isWhiteSpace(s[length-1]))) {
    179         return s;
    180     }
    181     int32_t start=0;
    182     int32_t limit=length;
    183     while(start<limit && isWhiteSpace(s[start])) {
    184         ++start;
    185     }
    186     if(start<limit) {
    187         // There is non-white space at start; we will not move limit below that,
    188         // so we need not test start<limit in the loop.
    189         while(isWhiteSpace(s[limit-1])) {
    190             --limit;
    191         }
    192     }
    193     length=limit-start;
    194     return s+start;
    195 }
    196 
    197 UBool
    198 PatternProps::isIdentifier(const UChar *s, int32_t length) {
    199     if(length<=0) {
    200         return FALSE;
    201     }
    202     const UChar *limit=s+length;
    203     do {
    204         if(isSyntaxOrWhiteSpace(*s++)) {
    205             return FALSE;
    206         }
    207     } while(s<limit);
    208     return TRUE;
    209 }
    210 
    211 const UChar *
    212 PatternProps::skipIdentifier(const UChar *s, int32_t length) {
    213     while(length>0 && !isSyntaxOrWhiteSpace(*s)) {
    214         ++s;
    215         --length;
    216     }
    217     return s;
    218 }
    219 
    220 U_NAMESPACE_END
    221