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Diffstat (limited to 'antlr-3.4/runtime/CSharp2/Sources/Antlr3.Runtime/Antlr.Runtime/ANTLRStringStream.cs')
| -rw-r--r-- | antlr-3.4/runtime/CSharp2/Sources/Antlr3.Runtime/Antlr.Runtime/ANTLRStringStream.cs | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/antlr-3.4/runtime/CSharp2/Sources/Antlr3.Runtime/Antlr.Runtime/ANTLRStringStream.cs b/antlr-3.4/runtime/CSharp2/Sources/Antlr3.Runtime/Antlr.Runtime/ANTLRStringStream.cs new file mode 100644 index 0000000..de12d58 --- /dev/null +++ b/antlr-3.4/runtime/CSharp2/Sources/Antlr3.Runtime/Antlr.Runtime/ANTLRStringStream.cs @@ -0,0 +1,285 @@ +/* + * [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. + */ + +namespace Antlr.Runtime { + using System.Collections.Generic; + using ArgumentException = System.ArgumentException; + using ArgumentOutOfRangeException = System.ArgumentOutOfRangeException; + using ArgumentNullException = System.ArgumentNullException; + + /** <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 ANTLRStringStream : ICharStream { + /** <summary>The data being scanned</summary> */ + 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; + + /** <summary>line number 1..n within the input</summary> */ + int line = 1; + + /** <summary>The index of the character relative to the beginning of the line 0..n-1</summary> */ + int charPositionInLine = 0; + + /** <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; + + /** <summary>Copy data in string to a local char array</summary> */ + public ANTLRStringStream(string input) + : this(input, null) { + } + + public ANTLRStringStream(string input, string sourceName) + : this(input.ToCharArray(), input.Length, sourceName) { + } + + /** <summary>This is the preferred constructor as no data is copied</summary> */ + public ANTLRStringStream(char[] data, int numberOfActualCharsInArray) + : this(data, numberOfActualCharsInArray, null) { + } + + public ANTLRStringStream(char[] data, int numberOfActualCharsInArray, string sourceName) { + if (data == null) + throw new ArgumentNullException("data"); + if (numberOfActualCharsInArray < 0) + throw new ArgumentOutOfRangeException(); + if (numberOfActualCharsInArray > data.Length) + throw new ArgumentException(); + + this.data = data; + this.n = numberOfActualCharsInArray; + this.name = sourceName; + } + + protected ANTLRStringStream() { + this.data = new char[0]; + } + + /** <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 virtual int Index { + get { + return p; + } + } + public virtual int Line { + get { + return line; + } + set { + line = value; + } + } + public virtual int CharPositionInLine { + get { + return charPositionInLine; + } + set { + charPositionInLine = value; + } + } + + /** <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 virtual void Reset() { + p = 0; + line = 1; + charPositionInLine = 0; + markDepth = 0; + } + + public virtual void Consume() { + //System.out.println("prev p="+p+", c="+(char)data[p]); + if (p < n) { + charPositionInLine++; + if (data[p] == '\n') { + /* + System.out.println("newline char found on line: "+line+ + "@ pos="+charPositionInLine); + */ + line++; + charPositionInLine = 0; + } + p++; + //System.out.println("p moves to "+p+" (c='"+(char)data[p]+"')"); + } + } + + public virtual 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 virtual int LT(int i) { + return LA(i); + } + + public virtual int Count { + get { + return n; + } + } + + public virtual 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; + state.line = line; + state.charPositionInLine = charPositionInLine; + lastMarker = markDepth; + return markDepth; + } + + public virtual void Rewind(int m) { + if (m < 0) + throw new ArgumentOutOfRangeException(); + + //if (m > markDepth) + // throw new ArgumentException(); + + CharStreamState state = markers[m]; + // restore stream state + Seek(state.p); + line = state.line; + charPositionInLine = state.charPositionInLine; + Release(m); + } + + public virtual void Rewind() { + Rewind(lastMarker); + } + + public virtual 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 virtual 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 virtual string Substring(int start, int length) { + if (start < 0) + throw new ArgumentOutOfRangeException(); + if (length < 0) + throw new ArgumentOutOfRangeException(); + if (start + length > data.Length) + throw new ArgumentException(); + + if (length == 0) + return string.Empty; + + return new string(data, start, length); + } + + public virtual string SourceName { + get { + return name; + } + } + + public override string ToString() { + return new string(data); + } + } +} |