src/stc/scintilla/src/StyleContext.h

   1 // Scintilla source code edit control
   2 /** @file StyleContext.cxx
   3  ** Lexer infrastructure.
   4  **/
   5 // Copyright 1998-2004 by Neil Hodgson <neilh@scintilla.org>
   6 // This file is in the public domain.
   7
   8 #ifdef SCI_NAMESPACE
   9 namespace Scintilla {
  10 #endif
  11
  12 // All languages handled so far can treat all characters >= 0x80 as one class
  13 // which just continues the current token or starts an identifier if in default.
  14 // DBCS treated specially as the second character can be < 0x80 and hence
  15 // syntactically significant. UTF-8 avoids this as all trail bytes are >= 0x80
  16 class StyleContext {
  17         Accessor &styler;
  18         unsigned int endPos;
  19         StyleContext& operator=(const StyleContext&) {
  20                 return *this;
  21         }
  22         void GetNextChar(unsigned int pos) {
  23                 chNext = static_cast<unsigned char>(styler.SafeGetCharAt(pos+1));
  24                 if (styler.IsLeadByte(static_cast<char>(chNext))) {
  25                         chNext = chNext << 8;
  26                         chNext |= static_cast<unsigned char>(styler.SafeGetCharAt(pos+2));
  27                 }
  28                 // End of line?
  29                 // Trigger on CR only (Mac style) or either on LF from CR+LF (Dos/Win)
  30                 // or on LF alone (Unix). Avoid triggering two times on Dos/Win.
  31                 atLineEnd = (ch == '\r' && chNext != '\n') ||
  32                                         (ch == '\n') ||
  33                                         (currentPos >= endPos);
  34         }
  35
  36 public:
  37         unsigned int currentPos;
  38         bool atLineStart;
  39         bool atLineEnd;
  40         int state;
  41         int chPrev;
  42         int ch;
  43         int chNext;
  44
  45         StyleContext(unsigned int startPos, unsigned int length,
  46                         int initStyle, Accessor &styler_, char chMask=31) :
  47                 styler(styler_),
  48                 endPos(startPos + length),
  49                 currentPos(startPos),
  50                 atLineStart(true),
  51                 atLineEnd(false),
  52                 state(initStyle & chMask), // Mask off all bits which aren't in the chMask.
  53                 chPrev(0),
  54                 ch(0),
  55                 chNext(0) {
  56                 styler.StartAt(startPos, chMask);
  57                 styler.StartSegment(startPos);
  58                 unsigned int pos = currentPos;
  59                 ch = static_cast<unsigned char>(styler.SafeGetCharAt(pos));
  60                 if (styler.IsLeadByte(static_cast<char>(ch))) {
  61                         pos++;
  62                         ch = ch << 8;
  63                         ch |= static_cast<unsigned char>(styler.SafeGetCharAt(pos));
  64                 }
  65                 GetNextChar(pos);
  66         }
  67         void Complete() {
  68                 styler.ColourTo(currentPos - 1, state);
  69         }
  70         bool More() {
  71                 return currentPos < endPos;
  72         }
  73         void Forward() {
  74                 if (currentPos < endPos) {
  75                         atLineStart = atLineEnd;
  76                         chPrev = ch;
  77                         currentPos++;
  78                         if (ch >= 0x100)
  79                                 currentPos++;
  80                         ch = chNext;
  81                         GetNextChar(currentPos + ((ch >= 0x100) ? 1 : 0));
  82                 } else {
  83                         atLineStart = false;
  84                         chPrev = ' ';
  85                         ch = ' ';
  86                         chNext = ' ';
  87                         atLineEnd = true;
  88                 }
  89         }
  90         void Forward(int nb) {
  91                 for (int i = 0; i < nb; i++) {
  92                         Forward();
  93                 }
  94         }
  95         void ChangeState(int state_) {
  96                 state = state_;
  97         }
  98         void SetState(int state_) {
  99                 styler.ColourTo(currentPos - 1, state);
 100                 state = state_;
 101         }
 102         void ForwardSetState(int state_) {
 103                 Forward();
 104                 styler.ColourTo(currentPos - 1, state);
 105                 state = state_;
 106         }
 107         int LengthCurrent() {
 108                 return currentPos - styler.GetStartSegment();
 109         }
 110         int GetRelative(int n) {
 111                 return static_cast<unsigned char>(styler.SafeGetCharAt(currentPos+n));
 112         }
 113         bool Match(char ch0) {
 114                 return ch == static_cast<unsigned char>(ch0);
 115         }
 116         bool Match(char ch0, char ch1) {
 117                 return (ch == static_cast<unsigned char>(ch0)) && (chNext == static_cast<unsigned char>(ch1));
 118         }
 119         bool Match(const char *s) {
 120                 if (ch != static_cast<unsigned char>(*s))
 121                         return false;
 122                 s++;
 123                 if (!*s)
 124                         return true;
 125                 if (chNext != static_cast<unsigned char>(*s))
 126                         return false;
 127                 s++;
 128                 for (int n=2; *s; n++) {
 129                         if (*s != styler.SafeGetCharAt(currentPos+n))
 130                                 return false;
 131                         s++;
 132                 }
 133                 return true;
 134         }
 135         bool MatchIgnoreCase(const char *s) {
 136                 if (tolower(ch) != static_cast<unsigned char>(*s))
 137                         return false;
 138                 s++;
 139                 if (tolower(chNext) != static_cast<unsigned char>(*s))
 140                         return false;
 141                 s++;
 142                 for (int n=2; *s; n++) {
 143                         if (static_cast<unsigned char>(*s) !=
 144                                 tolower(static_cast<unsigned char>(styler.SafeGetCharAt(currentPos+n))))
 145                                 return false;
 146                         s++;
 147                 }
 148                 return true;
 149         }
 150         // Non-inline
 151         void GetCurrent(char *s, unsigned int len);
 152         void GetCurrentLowered(char *s, unsigned int len);
 153 };
 154
 155 #ifdef SCI_NAMESPACE
 156 }
 157 #endif
 158
 159 inline bool IsASpace(unsigned int ch) {
 160     return (ch == ' ') || ((ch >= 0x09) && (ch <= 0x0d));
 161 }
 162
 163 inline bool IsASpaceOrTab(unsigned int ch) {
 164         return (ch == ' ') || (ch == '\t');
 165 }
 166
 167 inline bool IsADigit(unsigned int ch) {
 168         return (ch >= '0') && (ch <= '9');
 169 }
 170
 171 inline bool IsADigit(unsigned int ch, unsigned int base) {
 172         if (base <= 10) {
 173                 return (ch >= '0') && (ch < '0' + base);
 174         } else {
 175                 return ((ch >= '0') && (ch <= '9')) ||
 176                        ((ch >= 'A') && (ch < 'A' + base - 10)) ||
 177                        ((ch >= 'a') && (ch < 'a' + base - 10));
 178         }
 179 }