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/* ANTLRTokenBuffer.h |
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* |
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* SOFTWARE RIGHTS |
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* |
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* We reserve no LEGAL rights to the Purdue Compiler Construction Tool |
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* Set (PCCTS) -- PCCTS is in the public domain. An individual or |
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* company may do whatever they wish with source code distributed with |
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* PCCTS or the code generated by PCCTS, including the incorporation of |
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* PCCTS, or its output, into commerical software. |
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* |
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* We encourage users to develop software with PCCTS. However, we do ask |
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* that credit is given to us for developing PCCTS. By "credit", |
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* we mean that if you incorporate our source code into one of your |
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* programs (commercial product, research project, or otherwise) that you |
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* acknowledge this fact somewhere in the documentation, research report, |
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* etc... If you like PCCTS and have developed a nice tool with the |
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* output, please mention that you developed it using PCCTS. In |
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* addition, we ask that this header remain intact in our source code. |
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* As long as these guidelines are kept, we expect to continue enhancing |
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* this system and expect to make other tools available as they are |
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* completed. |
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* |
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* ANTLR 1.33 |
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* Terence Parr |
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* Parr Research Corporation |
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* with Purdue University and AHPCRC, University of Minnesota |
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* 1989-2000 |
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*/ |
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|
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#ifndef ATOKENBUFFER_H_GATE |
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#define ATOKENBUFFER_H_GATE |
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|
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#include "pcctscfg.h" |
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|
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#include "pccts_stdlib.h" |
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|
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PCCTS_NAMESPACE_STD |
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|
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#include ATOKEN_H |
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#include ATOKENSTREAM_H |
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|
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/* |
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* The parser is "attached" to an ANTLRTokenBuffer via interface |
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* functions: getToken() and bufferedToken(). The object that actually |
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* consumes characters and constructs tokens is connected to the |
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* ANTLRTokenBuffer via interface function ANTLRTokenStream::getToken(); |
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* where ANTLRTokenStream is really just a behavior (class with no data). |
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* C++ does not have this abstraction and hence we simply have come up |
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* with a fancy name for "void *". See the note in ANTLRTokenStream.h on |
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* the "behavior" of ANTLRTokenStream. |
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*/ |
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|
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class ANTLRParser; // MR1 |
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|
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class DllExportPCCTS ANTLRTokenBuffer { |
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protected: |
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ANTLRTokenStream *input; // where do I get tokens |
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int buffer_size; |
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int chunk_size; |
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int num_markers; |
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int k; // Need at least this many tokens in buffer |
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_ANTLRTokenPtr *buffer; // buffer used for arbitrary lookahead |
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_ANTLRTokenPtr *tp; // pts into buffer; current token ptr |
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_ANTLRTokenPtr *last; // pts to last valid token in buffer |
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_ANTLRTokenPtr *next; // place to put token from getANTLRToken() |
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_ANTLRTokenPtr *end_of_buffer; |
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/* when you try to write a token past this and there are no markers |
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set, then move k-1 tokens back to the beginning of the buffer. |
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We want to stay away from the end of the buffer because we have |
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to extend it if a marker is set and we reach the end (we cannot |
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move tokens to the beginning of the buffer in this case). |
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*/ |
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_ANTLRTokenPtr *threshold; |
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unsigned char _deleteTokens; |
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|
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// This function is filled in by the subclass; it initiates fetch of input |
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virtual _ANTLRTokenPtr getANTLRToken() { return input->getToken(); } |
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void makeRoom(); |
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void extendBuffer(); |
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|
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public: |
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ANTLRTokenBuffer(ANTLRTokenStream *in, int k=1, int chksz=50); |
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virtual ~ANTLRTokenBuffer(); |
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virtual _ANTLRTokenPtr getToken(); |
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virtual void rewind(int pos); |
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virtual int mark(); |
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virtual _ANTLRTokenPtr bufferedToken(int i); |
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|
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void noGarbageCollectTokens() { _deleteTokens=0; } |
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void garbageCollectTokens() { _deleteTokens=1; } |
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|
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virtual int bufferSize() { return buffer_size; } |
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virtual int minTokens() { return k; } |
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virtual void setMinTokens(int k_new) { k = k_new; } |
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|
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virtual void panic(const char *msg); /* MR20 const */ |
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|
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virtual int printMessage(FILE* pFile, const char* pFormat, ...); // MR23 |
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|
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protected: // MR1 |
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ANTLRParser *parser; // MR1 |
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public: // MR1 |
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ANTLRParser *setParser(ANTLRParser *p); // MR1 |
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ANTLRParser *getParser(); // MR1 |
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ANTLRTokenStream *getLexer() const { // MR12 |
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return input;} // MR12 |
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}; |
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|
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#endif |