hlslTokenStream.h

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#ifndef HLSLTOKENSTREAM_H_
#define HLSLTOKENSTREAM_H_

#include "hlslScanContext.h"

namespace glslang {

 class HlslTokenStream {
 public:
 explicit HlslTokenStream(HlslScanContext& scanner)
 : scanner(scanner), preTokenStackSize(0), tokenBufferPos(0) { }
 virtual ~HlslTokenStream() { }

 public:
 void advanceToken();
 void recedeToken();
 bool acceptTokenClass(EHlslTokenClass);
 EHlslTokenClass peek() const;
 bool peekTokenClass(EHlslTokenClass) const;
 glslang::TBuiltInVariable mapSemantic(const char* upperCase) { return scanner.mapSemantic(upperCase); }

 void pushTokenStream(const TVector<HlslToken>* tokens);
 void popTokenStream();

 protected:
 HlslToken token; // the token we are currently looking at, but have not yet accepted

 private:
 HlslTokenStream();
 HlslTokenStream& operator=(const HlslTokenStream&);

 HlslScanContext& scanner; // lexical scanner, to get next token from source file
 TVector<const TVector<HlslToken>*> tokenStreamStack; // for getting the next token from an existing vector of tokens
 TVector<int> tokenPosition;
 TVector<HlslToken> currentTokenStack;

 // This is the number of tokens we can recedeToken() over.
 static const int tokenBufferSize = 2;

 // Previously scanned tokens, returned for future advances,
 // so logically in front of the token stream.
 // Is logically a stack; needs last in last out semantics.
 // Currently implemented as a stack of size 2.
 HlslToken preTokenStack[tokenBufferSize];
 int preTokenStackSize;
 void pushPreToken(const HlslToken&);
 HlslToken popPreToken();

 // Previously scanned tokens, not yet returned for future advances,
 // but available for that.
 // Is logically a fifo for normal advances, and a stack for recession.
 // Currently implemented with an intrinsic size of 2.
 HlslToken tokenBuffer[tokenBufferSize];
 int tokenBufferPos;
 void pushTokenBuffer(const HlslToken&);
 HlslToken popTokenBuffer();
 };

} // end namespace glslang

#endif // HLSLTOKENSTREAM_H_