icuSources/common/patternprops.cpp

   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