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authorMichele Calgaro <michele.calgaro@yahoo.it>2020-12-17 20:50:19 +0900
committerMichele Calgaro <michele.calgaro@yahoo.it>2020-12-17 23:50:37 +0900
commit3e3d9eda9d1dd8c67c1c27c6a9bdc68bdecfcc30 (patch)
tree6af0b8ba2786060423ba143e894bf9529d351f8d /lib/antlr/antlr/InputBuffer.h
parentf08b30edb9f422128083050320681b6bacd06d1d (diff)
downloadtdevelop-3e3d9eda9d1dd8c67c1c27c6a9bdc68bdecfcc30.tar.gz
tdevelop-3e3d9eda9d1dd8c67c1c27c6a9bdc68bdecfcc30.zip
Renaming of files in preparation for code style tools.
Signed-off-by: Michele Calgaro <michele.calgaro@yahoo.it>
Diffstat (limited to 'lib/antlr/antlr/InputBuffer.h')
-rw-r--r--lib/antlr/antlr/InputBuffer.h146
1 files changed, 146 insertions, 0 deletions
diff --git a/lib/antlr/antlr/InputBuffer.h b/lib/antlr/antlr/InputBuffer.h
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+#ifndef INC_InputBuffer_h__
+#define INC_InputBuffer_h__
+
+/* ANTLR Translator Generator
+ * Project led by Terence Parr at http://www.jGuru.com
+ * Software rights: http://www.antlr.org/license.html
+ *
+ * $Id$
+ */
+
+#include <antlr/config.h>
+#include <antlr/CircularQueue.h>
+#include <string>
+
+#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
+namespace antlr {
+#endif
+
+/** A Stream of characters fed to the lexer from a InputStream that can
+ * be rewound via mark()/rewind() methods.
+ * <p>
+ * A dynamic array is used to buffer up all the input characters. Normally,
+ * "k" characters are stored in the buffer. More characters may be stored during
+ * guess mode (testing syntactic predicate), or when LT(i>k) is referenced.
+ * Consumption of characters is deferred. In other words, reading the next
+ * character is not done by conume(), but deferred until needed by LA or LT.
+ * <p>
+ *
+ * @see antlr.CharQueue
+ */
+class ANTLR_API InputBuffer {
+public:
+ /** Create a character buffer */
+ InputBuffer()
+ : nMarkers(0)
+ , markerOffset(0)
+ , numToConsume(0)
+ {
+ }
+
+ virtual ~InputBuffer()
+ {
+ }
+
+ /// Reset the input buffer to empty state
+ virtual inline void reset( void )
+ {
+ nMarkers = 0;
+ markerOffset = 0;
+ numToConsume = 0;
+ queue.clear();
+ }
+
+ /** This method updates the state of the input buffer so that
+ * the text matched since the most recent mark() is no longer
+ * held by the buffer. So, you either do a mark/rewind for
+ * failed predicate or mark/commit to keep on parsing without
+ * rewinding the input.
+ */
+ inline void commit( void )
+ {
+ nMarkers--;
+ }
+
+ /** Mark another character for deferred consumption */
+ virtual inline void consume()
+ {
+ numToConsume++;
+ }
+
+ /** Ensure that the character buffer is sufficiently full */
+ virtual void fill(unsigned int amount);
+
+ /** Override this in subclasses to get the next character */
+ virtual int getChar()=0;
+
+ /** Get a lookahead character */
+ virtual inline int LA(unsigned int i)
+ {
+ fill(i);
+ return queue.elementAt(markerOffset + i - 1);
+ }
+
+ /** Return an integer marker that can be used to rewind the buffer to
+ * its current state.
+ */
+ virtual unsigned int mark();
+ /// Are there any marks active in the InputBuffer
+ virtual inline bool isMarked() const
+ {
+ return (nMarkers != 0);
+ }
+ /** Rewind the character buffer to a marker.
+ * @param mark Marker returned previously from mark()
+ */
+ virtual void rewind(unsigned int mark);
+
+ /** Get the number of non-consumed characters
+ */
+ virtual unsigned int entries() const;
+
+ ANTLR_USE_NAMESPACE(std)string getLAChars() const;
+
+ ANTLR_USE_NAMESPACE(std)string getMarkedChars() const;
+
+protected:
+ // char source
+ // leave to subclasses
+
+ // Number of active markers
+ unsigned int nMarkers; // = 0;
+
+ // Additional offset used when markers are active
+ unsigned int markerOffset; // = 0;
+
+ // Number of calls to consume() since last LA() or LT() call
+ unsigned int numToConsume; // = 0;
+
+ // Circular queue
+ CircularQueue<int> queue;
+
+ /** Sync up deferred consumption */
+ void syncConsume();
+
+private:
+ InputBuffer(const InputBuffer& other);
+ InputBuffer& operator=(const InputBuffer& other);
+};
+
+/** Sync up deferred consumption */
+inline void InputBuffer::syncConsume() {
+ if (numToConsume > 0)
+ {
+ if (nMarkers > 0)
+ markerOffset += numToConsume;
+ else
+ queue.removeItems( numToConsume );
+ numToConsume = 0;
+ }
+}
+
+#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
+}
+#endif
+
+#endif //INC_InputBuffer_h__