src/stc/scintilla/include/Accessor.h

   1 // SciTE - Scintilla based Text Editor
   2 // Accessor.h - rapid easy access to contents of a Scintilla
   3 // Copyright 1998-2000 by Neil Hodgson <neilh@scintilla.org>
   4 // The License.txt file describes the conditions under which this software may be distributed.
   5
   6 enum { wsSpace = 1, wsTab = 2, wsSpaceTab = 4, wsInconsistent=8};
   7
   8 class Accessor {
   9 protected:
  10         // bufferSize is a trade off between time taken to copy the characters and SendMessage overhead
  11         // slopSize positions the buffer before the desired position in case there is some backtracking
  12         enum {bufferSize=4000, slopSize=bufferSize/8};
  13         char buf[bufferSize+1];
  14         WindowID id;
  15         PropSet &props;
  16         int startPos;
  17         int endPos;
  18         int lenDoc;
  19         int offset;     // Optional but including an offset makes GCC generate better code
  20         int codePage;
  21         bool InternalIsLeadByte(char ch);
  22         void Fill(int position);
  23 public:
  24         Accessor(WindowID id_, PropSet &props_, int offset_=0) :
  25                         id(id_), props(props_), startPos(0x7FFFFFFF), endPos(0),
  26                         lenDoc(-1), offset(offset_), codePage(0) {
  27         }
  28         void SetCodePage(int codePage_) { codePage = codePage_; }
  29         char operator[](int position) {
  30                 position += offset;
  31                 if (position < startPos || position >= endPos) {
  32                         Fill(position);
  33                 }
  34                 return buf[position - startPos];
  35         }
  36         char SafeGetCharAt(int position, char chDefault=' ') {
  37                 // Safe version of operator[], returning a defined value for invalid position
  38                 position += offset;
  39                 if (position < startPos || position >= endPos) {
  40                         Fill(position);
  41                         if (position < startPos || position >= endPos) {
  42                                 // Position is outside range of document
  43                                 return chDefault;
  44                         }
  45                 }
  46                 return buf[position - startPos];
  47         }
  48         bool IsLeadByte(char ch) {
  49                 return codePage && InternalIsLeadByte(ch);
  50         }
  51         char StyleAt(int position);
  52         int GetLine(int position);
  53         int LineStart(int line);
  54         int LevelAt(int line);
  55         int Length();
  56         void Flush() {
  57                 startPos = 0x7FFFFFFF;
  58                 lenDoc = -1;
  59         }
  60         int GetLineState(int line);
  61         int SetLineState(int line, int state);
  62         PropSet &GetPropSet() { return props; }
  63 };
  64
  65 class StylingContext;
  66
  67 typedef bool (*PFNIsCommentLeader)(StylingContext &styler, int pos, int len);
  68
  69 class StylingContext : public Accessor {
  70         char styleBuf[bufferSize];
  71         int validLen;
  72         char chFlags;
  73         char chWhile;
  74         unsigned int startSeg;
  75 public:
  76         StylingContext(WindowID id_, PropSet &props_, int offset_=0) :
  77                 Accessor(id_,props_,offset_), validLen(0), chFlags(0) {}
  78         void StartAt(unsigned int start, char chMask=31);
  79         void SetFlags(char chFlags_, char chWhile_) {chFlags = chFlags_; chWhile = chWhile_; };
  80         unsigned int GetStartSegment() { return startSeg; }
  81         void StartSegment(unsigned int pos);
  82         void ColourTo(unsigned int pos, int chAttr);
  83         int GetLine(int position);
  84         void SetLevel(int line, int level);
  85         void Flush();
  86         int IndentAmount(int line, int *flags, PFNIsCommentLeader pfnIsCommentLeader = 0);
  87 };
  88