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Diffstat (limited to 'runtime/CSharp3/Sources/Antlr3.Runtime.Test/SlimParsing/SlimStringStream.cs')
| -rw-r--r-- | runtime/CSharp3/Sources/Antlr3.Runtime.Test/SlimParsing/SlimStringStream.cs | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/runtime/CSharp3/Sources/Antlr3.Runtime.Test/SlimParsing/SlimStringStream.cs b/runtime/CSharp3/Sources/Antlr3.Runtime.Test/SlimParsing/SlimStringStream.cs new file mode 100644 index 0000000..b2c5d54 --- /dev/null +++ b/runtime/CSharp3/Sources/Antlr3.Runtime.Test/SlimParsing/SlimStringStream.cs @@ -0,0 +1,334 @@ +/* + * [The "BSD licence"] + * Copyright (c) 2005-2008 Terence Parr + * All rights reserved. + * + * Conversion to C#: + * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +// #define TRACK_POSITION + +namespace Antlr.Runtime +{ + using System.Collections.Generic; + + /** <summary> + * A pretty quick CharStream that pulls all data from an array + * directly. Every method call counts in the lexer. Java's + * strings aren't very good so I'm avoiding. + * </summary> + */ + [System.Serializable] + public class SlimStringStream : ICharStream + { + /** <summary>The data being scanned</summary> */ + protected string data; + //protected char[] data; + + /** <summary>How many characters are actually in the buffer</summary> */ + protected int n; + + /** <summary>0..n-1 index into string of next char</summary> */ + protected int p = 0; + +#if TRACK_POSITION + /** <summary>line number 1..n within the input</summary> */ + protected int line = 1; + + /** <summary>The index of the character relative to the beginning of the line 0..n-1</summary> */ + protected int charPositionInLine = 0; +#endif + + /** <summary>tracks how deep mark() calls are nested</summary> */ + protected int markDepth = 0; + + /** <summary> + * A list of CharStreamState objects that tracks the stream state + * values line, charPositionInLine, and p that can change as you + * move through the input stream. Indexed from 1..markDepth. + * A null is kept @ index 0. Create upon first call to mark(). + * </summary> + */ + protected IList<CharStreamState> markers; + + /** <summary>Track the last mark() call result value for use in rewind().</summary> */ + protected int lastMarker; + + /** <summary>What is name or source of this char stream?</summary> */ + public string name; + + public SlimStringStream() + { + } + + /** <summary>Copy data in string to a local char array</summary> */ + public SlimStringStream( string input ) + : this( input, null ) + { + } + + public SlimStringStream( string input, string sourceName ) + : this( input.ToCharArray(), input.Length, sourceName ) + { + } + + /** <summary>This is the preferred constructor as no data is copied</summary> */ + public SlimStringStream( char[] data, int numberOfActualCharsInArray ) + : this( data, numberOfActualCharsInArray, null ) + { + } + + public SlimStringStream( char[] data, int numberOfActualCharsInArray, string sourceName ) + : this() + { + //this.data = data; + this.data = new string( data ); + this.n = numberOfActualCharsInArray; + this.name = sourceName; + } + + /** <summary> + * Return the current input symbol index 0..n where n indicates the + * last symbol has been read. The index is the index of char to + * be returned from LA(1). + * </summary> + */ + public int Index + { + get + { + return p; + } + } +#if TRACK_POSITION + public int Line + { + get + { + return line; + } + set + { + line = value; + } + } + public int CharPositionInLine + { + get + { + return charPositionInLine; + } + set + { + charPositionInLine = value; + } + } +#else + public int Line + { + get + { + return -1; + } + set + { + } + } + public int CharPositionInLine + { + get + { + return -1; + } + set + { + } + } +#endif + + /** <summary> + * Reset the stream so that it's in the same state it was + * when the object was created *except* the data array is not + * touched. + * </summary> + */ + public void Reset() + { + p = 0; +#if TRACK_POSITION + line = 1; + charPositionInLine = 0; +#endif + markDepth = 0; + } + + public void Consume() + { + //System.out.println("prev p="+p+", c="+(char)data[p]); + if ( p < n ) + { +#if TRACK_POSITION + charPositionInLine++; + if ( data[p] == '\n' ) + { + /* + System.out.println("newline char found on line: "+line+ + "@ pos="+charPositionInLine); + */ + line++; + charPositionInLine = 0; + } +#endif + p++; + //System.out.println("p moves to "+p+" (c='"+(char)data[p]+"')"); + } + } + + public int LA( int i ) + { + if ( i == 0 ) + { + return 0; // undefined + } + if ( i < 0 ) + { + i++; // e.g., translate LA(-1) to use offset i=0; then data[p+0-1] + if ( ( p + i - 1 ) < 0 ) + { + return CharStreamConstants.EndOfFile; // invalid; no char before first char + } + } + + if ( ( p + i - 1 ) >= n ) + { + //System.out.println("char LA("+i+")=EOF; p="+p); + return CharStreamConstants.EndOfFile; + } + //System.out.println("char LA("+i+")="+(char)data[p+i-1]+"; p="+p); + //System.out.println("LA("+i+"); p="+p+" n="+n+" data.length="+data.length); + return data[p + i - 1]; + } + + public int LT( int i ) + { + return LA( i ); + } + + public int Count + { + get + { + return n; + } + } + + public int Mark() + { + if ( markers == null ) + { + markers = new List<CharStreamState>(); + markers.Add( null ); // depth 0 means no backtracking, leave blank + } + markDepth++; + CharStreamState state = null; + if ( markDepth >= markers.Count ) + { + state = new CharStreamState(); + markers.Add( state ); + } + else + { + state = markers[markDepth]; + } + state.p = p; +#if TRACK_POSITION + state.line = line; + state.charPositionInLine = charPositionInLine; +#endif + lastMarker = markDepth; + return markDepth; + } + + public void Rewind( int m ) + { + CharStreamState state = markers[m]; + // restore stream state + Seek( state.p ); +#if TRACK_POSITION + line = state.line; + charPositionInLine = state.charPositionInLine; +#endif + Release( m ); + } + + public void Rewind() + { + Rewind( lastMarker ); + } + + public void Release( int marker ) + { + // unwind any other markers made after m and release m + markDepth = marker; + // release this marker + markDepth--; + } + + /** <summary> + * consume() ahead until p==index; can't just set p=index as we must + * update line and charPositionInLine. + * </summary> + */ + public void Seek( int index ) + { + if ( index <= p ) + { + p = index; // just jump; don't update stream state (line, ...) + return; + } + // seek forward, consume until p hits index + while ( p < index ) + { + Consume(); + } + } + + public string Substring( int start, int length ) + { + return data.Substring( start, length ); + //return new string( data, start, stop - start + 1 ); + } + + public string SourceName + { + get + { + return name; + } + } + } +} |