src/stc/scintilla/src/StyleContext.h

   1 // Scintilla source code edit control
   2 /** @file StyleContext.cxx
   3  ** Lexer infrastructure.
   4  **/
   5 // Copyright 1998-2001 by Neil Hodgson <neilh@scintilla.org>
   6 // This file is in the public domain.
   7
   8 // All languages handled so far can treat all characters >= 0x80 as one class
   9 // which just continues the current token or starts an identifier if in default.
  10 // DBCS treated specially as the second character can be < 0x80 and hence
  11 // syntactically significant. UTF-8 avoids this as all trail bytes are >= 0x80
  12 class StyleContext {
  13         Accessor &styler;
  14         int endPos;
  15         StyleContext& operator=(const StyleContext&) {
  16                 return *this;
  17         }
  18 public:
  19         int currentPos;
  20         bool atLineStart;
  21         bool atLineEnd;
  22         int state;
  23         int chPrev;
  24         int ch;
  25         int chNext;
  26
  27         StyleContext(unsigned int startPos, int length,
  28                         int initStyle, Accessor &styler_, char chMask=31) :
  29                 styler(styler_),
  30                 endPos(startPos + length),
  31                 currentPos(startPos),
  32                 atLineStart(true),
  33                 atLineEnd(false),
  34                 state(initStyle),
  35                 chPrev(0),
  36                 ch(0),
  37                 chNext(0) {
  38                 styler.StartAt(startPos, chMask);
  39                 styler.StartSegment(startPos);
  40                 int pos = currentPos;
  41                 ch = static_cast<unsigned char>(styler.SafeGetCharAt(pos));
  42                 if (styler.IsLeadByte(static_cast<char>(ch))) {
  43                         pos++;
  44                         ch = ch << 8;
  45                         ch |= static_cast<unsigned char>(styler.SafeGetCharAt(pos));
  46                 }
  47                 chNext = static_cast<unsigned char>(styler.SafeGetCharAt(pos+1));
  48                 if (styler.IsLeadByte(static_cast<char>(chNext))) {
  49                         chNext = chNext << 8;
  50                         chNext |= static_cast<unsigned char>(styler.SafeGetCharAt(pos+2));
  51                 }
  52                 atLineEnd = (ch == '\r' && chNext != '\n') || (ch == '\n') || (currentPos >= endPos);
  53         }
  54         void Complete() {
  55                 styler.ColourTo(currentPos - 1, state);
  56         }
  57         bool More() {
  58                 return currentPos < endPos;
  59         }
  60         void Forward() {
  61                 if (currentPos < endPos) {
  62                         atLineStart = atLineEnd;
  63                         // A lot of this is repeated from the constructor - TODO: merge code
  64                         chPrev = ch;
  65                         currentPos++;
  66                         if (ch >= 0x100)
  67                                 currentPos++;
  68                         ch = chNext;
  69                         chNext = static_cast<unsigned char>(styler.SafeGetCharAt(currentPos+1));
  70                         if (styler.IsLeadByte(static_cast<char>(chNext))) {
  71                                 chNext = chNext << 8;
  72                                 chNext |= static_cast<unsigned char>(styler.SafeGetCharAt(currentPos + 2));
  73                         }
  74                         // Trigger on CR only (Mac style) or either on LF from CR+LF (Dos/Win) or on LF alone (Unix)
  75                         // Avoid triggering two times on Dos/Win
  76                         // End of line
  77                         atLineEnd = (ch == '\r' && chNext != '\n') || (ch == '\n') || (currentPos >= endPos);
  78                 } else {
  79                         atLineStart = false;
  80                         chPrev = ' ';
  81                         ch = ' ';
  82                         chNext = ' ';
  83                         atLineEnd = true;
  84                 }
  85         }
  86         void ChangeState(int state_) {
  87                 state = state_;
  88         }
  89         void SetState(int state_) {
  90                 styler.ColourTo(currentPos - 1, state);
  91                 state = state_;
  92         }
  93         void ForwardSetState(int state_) {
  94                 Forward();
  95                 styler.ColourTo(currentPos - 1, state);
  96                 state = state_;
  97         }
  98         int LengthCurrent() {
  99                 return currentPos - styler.GetStartSegment();
 100         }
 101         int GetRelative(int n) {
 102                 return styler.SafeGetCharAt(currentPos+n);
 103         }
 104         bool Match(char ch0) {
 105                 return ch == ch0;
 106         }
 107         bool Match(char ch0, char ch1) {
 108                 return (ch == ch0) && (chNext == ch1);
 109         }
 110         bool Match(const char *s) {
 111                 if (ch != *s)
 112                         return false;
 113                 s++;
 114                 if (chNext != *s)
 115                         return false;
 116                 s++;
 117                 for (int n=2; *s; n++) {
 118                         if (*s != styler.SafeGetCharAt(currentPos+n))
 119                                 return false;
 120                         s++;
 121                 }
 122                 return true;
 123         }
 124         bool MatchIgnoreCase(const char *s) {
 125                 if (tolower(ch) != *s)
 126                         return false;
 127                 s++;
 128                 if (tolower(chNext) != *s)
 129                         return false;
 130                 s++;
 131                 for (int n=2; *s; n++) {
 132                         if (*s != tolower((styler.SafeGetCharAt(currentPos+n))))
 133                                 return false;
 134                         s++;
 135                 }
 136                 return true;
 137         }
 138         // Non-inline
 139         void GetCurrent(char *s, int len);
 140         void GetCurrentLowered(char *s, int len);
 141 };
 142
 143 inline bool IsASpace(unsigned int ch) {
 144     return (ch == ' ') || ((ch >= 0x09) && (ch <= 0x0d));
 145 }
 146
 147 inline bool IsASpaceOrTab(unsigned int ch) {
 148         return (ch == ' ') || (ch == '\t');
 149 }
 150
 151 inline bool IsADigit(unsigned int ch) {
 152         return (ch >= '0') && (ch <= '9');
 153 }