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35 
36 #ifndef HLSLTOKENSTREAM_H_
37 #define HLSLTOKENSTREAM_H_
38 
39 #include "hlslScanContext.h"
40 
41 namespace glslang {
42 
43     class HlslTokenStream {
44     public:
HlslTokenStream(HlslScanContext & scanner)45         explicit HlslTokenStream(HlslScanContext& scanner)
46             : scanner(scanner), preTokenStackSize(0), tokenBufferPos(0) { }
~HlslTokenStream()47         virtual ~HlslTokenStream() { }
48 
49     public:
50         void advanceToken();
51         void recedeToken();
52         bool acceptTokenClass(EHlslTokenClass);
53         EHlslTokenClass peek() const;
54         bool peekTokenClass(EHlslTokenClass) const;
mapSemantic(const char * upperCase)55         glslang::TBuiltInVariable mapSemantic(const char* upperCase) { return scanner.mapSemantic(upperCase); }
56 
57         void pushTokenStream(const TVector<HlslToken>* tokens);
58         void popTokenStream();
59 
60     protected:
61         HlslToken token;                  // the token we are currently looking at, but have not yet accepted
62 
63     private:
64         HlslTokenStream();
65         HlslTokenStream& operator=(const HlslTokenStream&);
66 
67         HlslScanContext& scanner;         // lexical scanner, to get next token from source file
68         TVector<const TVector<HlslToken>*> tokenStreamStack; // for getting the next token from an existing vector of tokens
69         TVector<int> tokenPosition;
70         TVector<HlslToken> currentTokenStack;
71 
72         // This is the number of tokens we can recedeToken() over.
73         static const int tokenBufferSize = 2;
74 
75         // Previously scanned tokens, returned for future advances,
76         // so logically in front of the token stream.
77         // Is logically a stack; needs last in last out semantics.
78         // Currently implemented as a stack of size 2.
79         HlslToken preTokenStack[tokenBufferSize];
80         int preTokenStackSize;
81         void pushPreToken(const HlslToken&);
82         HlslToken popPreToken();
83 
84         // Previously scanned tokens, not yet returned for future advances,
85         // but available for that.
86         // Is logically a fifo for normal advances, and a stack for recession.
87         // Currently implemented with an intrinsic size of 2.
88         HlslToken tokenBuffer[tokenBufferSize];
89         int tokenBufferPos;
90         void pushTokenBuffer(const HlslToken&);
91         HlslToken popTokenBuffer();
92     };
93 
94 } // end namespace glslang
95 
96 #endif // HLSLTOKENSTREAM_H_
97