hlsl/hlslScanContext.h

//
// Copyright (C) 2016 Google, Inc.
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//
// This holds context specific to the HLSL scanner, which
// sits between the preprocessor scanner and HLSL parser.
//

#ifndef HLSLSCANCONTEXT_H_
#define HLSLSCANCONTEXT_H_

#include "../glslang/MachineIndependent/ParseHelper.h"
#include "hlslTokens.h"

namespace glslang {

class TPpContext;
class TPpToken;


//
// Everything needed to fully describe a token.
//
struct HlslToken {
    HlslToken() : string(nullptr) { loc.init(); }
    TSourceLoc loc;                // location of token in the source
    EHlslTokenClass tokenClass;    // what kind of token it is
    union {                        // what data the token holds
        glslang::TString *string;  // for identifiers
        int i;                     // for literals
        unsigned int u;
        bool b;
        double d;
    };
};

//
// The state of scanning and translating raw tokens to slightly richer
// semantics, like knowing if an identifier is an existing symbol, or
// user-defined type.
//
class HlslScanContext {
public:
    HlslScanContext(TParseContextBase& parseContext, TPpContext& ppContext)
        : parseContext(parseContext), ppContext(ppContext) { }
    virtual ~HlslScanContext() { }

    static void fillInKeywordMap();
    static void deleteKeywordMap();

    void tokenize(HlslToken&);
    glslang::TBuiltInVariable mapSemantic(const char*);

protected:
    HlslScanContext(HlslScanContext&);
    HlslScanContext& operator=(HlslScanContext&);

    EHlslTokenClass tokenizeClass(HlslToken&);
    EHlslTokenClass tokenizeIdentifier();
    EHlslTokenClass identifierOrType();
    EHlslTokenClass reservedWord();
    EHlslTokenClass identifierOrReserved(bool reserved);
    EHlslTokenClass nonreservedKeyword(int version);

    TParseContextBase& parseContext;
    TPpContext& ppContext;
    TSourceLoc loc;
    TPpToken* ppToken;
    HlslToken* parserToken;

    const char* tokenText;
    EHlslTokenClass keyword;
};

} // end namespace glslang

#endif // HLSLSCANCONTEXT_H_