Security-57031.1.35.tar.gz

[apple/security.git] / Security / libsecurity_codesigning / antlr2 / antlr / TokenBuffer.hpp

diff --git a/Security/libsecurity_codesigning/antlr2/antlr/TokenBuffer.hpp b/Security/libsecurity_codesigning/antlr2/antlr/TokenBuffer.hpp
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+#ifndef INC_TokenBuffer_hpp__
+#define INC_TokenBuffer_hpp__
+
+/* ANTLR Translator Generator
+ * Project led by Terence Parr at http://www.jGuru.com
+ * Software rights: http://www.antlr.org/license.html
+ *
+ * $Id: //depot/code/org.antlr/release/antlr-2.7.7/lib/cpp/antlr/TokenBuffer.hpp#2 $
+ */
+
+#include <antlr/config.hpp>
+#include <antlr/TokenStream.hpp>
+#include <antlr/CircularQueue.hpp>
+
+#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
+namespace antlr {
+#endif
+
+/**A Stream of Token objects fed to the parser from a TokenStream that can
+ * be rewound via mark()/rewind() methods.
+ * <p>
+ * A dynamic array is used to buffer up all the input tokens.  Normally,
+ * "k" tokens are stored in the buffer.  More tokens may be stored during
+ * guess mode (testing syntactic predicate), or when LT(i>k) is referenced.
+ * Consumption of tokens is deferred.  In other words, reading the next
+ * token is not done by conume(), but deferred until needed by LA or LT.
+ * <p>
+ *
+ * @todo: see if we can integrate this one with InputBuffer into one template
+ * or so.
+ *
+ * @see antlr.Token
+ * @see antlr.TokenStream
+ * @see antlr.TokenQueue
+ */
+class ANTLR_API TokenBuffer {
+public:
+       /** Create a token buffer */
+       TokenBuffer(TokenStream& input_);
+       virtual ~TokenBuffer();
+
+       /// Reset the input buffer to empty state
+       inline void reset( void )
+       {
+               nMarkers = 0;
+               markerOffset = 0;
+               numToConsume = 0;
+               queue.clear();
+       }
+
+       /** Get a lookahead token value */
+       int LA( unsigned int i );
+
+       /** Get a lookahead token */
+       RefToken LT( unsigned int i );
+
+       /** Return an integer marker that can be used to rewind the buffer to
+        * its current state.
+        */
+       unsigned int mark();
+
+       /**Rewind the token buffer to a marker.
+        * @param mark Marker returned previously from mark()
+        */
+       void rewind(unsigned int mark);
+
+       /** Mark another token for deferred consumption */
+       inline void consume()
+       {
+               numToConsume++;
+       }
+
+       /// Return the number of entries in the TokenBuffer
+       virtual unsigned int entries() const;
+
+private:
+       /** Ensure that the token buffer is sufficiently full */
+       void fill(unsigned int amount);
+       /** Sync up deferred consumption */
+       void syncConsume();
+
+protected:
+       /// Token source
+       TokenStream& input;
+
+       /// Number of active markers
+       unsigned int nMarkers;
+
+       /// Additional offset used when markers are active
+       unsigned int markerOffset;
+
+       /// Number of calls to consume() since last LA() or LT() call
+       unsigned int numToConsume;
+
+       /// Circular queue with Tokens
+       CircularQueue<RefToken> queue;
+
+private:
+       TokenBuffer(const TokenBuffer& other);
+       const TokenBuffer& operator=(const TokenBuffer& other);
+};
+
+/** Sync up deferred consumption */
+inline void TokenBuffer::syncConsume()
+{
+       if (numToConsume > 0)
+       {
+               if (nMarkers > 0)
+                       markerOffset += numToConsume;
+               else
+                       queue.removeItems( numToConsume );
+
+               numToConsume = 0;
+       }
+}
+
+#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
+}
+#endif
+
+#endif //INC_TokenBuffer_hpp__