icuSources/common/patternprops.cpp

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