--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/debugger/InputLexer.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,212 @@
+/*
+ * Copyright 2000-2001 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+package sun.jvm.hotspot.debugger;
+
+import java.io.*;
+
+/** InputLexer is the lexer through which the current set of debuggers
+    see the debug server. It provides the ability to read all of the
+    types the debuggers are interested in. All read operations are
+    blocking. */
+
+public class InputLexer {
+  public InputLexer(BufferedInputStream in) throws IOException {
+    this.in = in;
+    pushedBack = false;
+  }
+
+  public void close() throws IOException {
+    in.close();
+  }
+
+  /** Parses a boolean (really either a 0 or 1 integer in US-ASCII
+      encoding) on the input stream */
+  public boolean parseBoolean() throws IOException {
+    int val = parseInt();
+    return (val != 0);
+  }
+
+  /** Parses an int in US-ASCII encoding on the input stream */
+  public int parseInt() throws IOException {
+    long l = parseLong();
+    long mask = 0xFFFFFFFF00000000L;
+    if ((l & mask) != 0) {
+      throw new IOException("Overflow error reading int from debug server (read " + l + ")");
+    }
+    return (int) l;
+  }
+
+  /** Parses a long in US-ASCII encoding on the input stream */
+  public long parseLong() throws IOException {
+    skipWhitespace();
+    byte b = readByte();
+    if (!Character.isDigit((char) b)) {
+      error();
+    }
+    long l = 0;
+    while (Character.isDigit((char) b)) {
+      l *= 10;
+      l += (b - '0');
+      b = readByte();
+    }
+    pushBack(b);
+    return l;
+  }
+
+  /** Parses an address in the form 0x12345678 in US-ASCII encoding on
+      the input stream */
+  public long parseAddress() throws IOException {
+    skipWhitespace();
+    byte b;
+    if ((b = readByte()) != '0') {
+      error();
+    }
+    b = readByte();
+    if (b != 'x') {
+      error();
+    }
+    long val = 0;
+    while (isHexDigit((char) (b = readByte()))) {
+      val *= 16;
+      val += Character.digit((char) b, 16);
+    }
+    pushBack(b);
+    return val;
+  }
+
+  public void skipByte() throws IOException {
+    readByte();
+  }
+
+  /** Reads binary data; one byte */
+  public byte readByte() throws IOException {
+    if (pushedBack) {
+      pushedBack = false;
+      return backBuf;
+    }
+    return readByteInternal();
+  }
+
+  /** Reads a block of binary data in BLOCKING fashion */
+  public void readBytes(byte[] buf, int off, int len) throws IOException {
+    int startIdx = off;
+    int numRead = 0;
+    if (pushedBack) {
+      buf[startIdx] = backBuf;
+      pushedBack = false;
+      ++startIdx;
+      ++numRead;
+    }
+    while (numRead < len) {
+      numRead += in.read(buf, startIdx + numRead, len - numRead);
+    }
+    //    if (numRead != len) {
+    //      throw new IOException("Only read " + numRead + " out of " +
+    //                            len + " bytes requested");
+    //    }
+  }
+
+  /** Reads binary data; one 16-bit character in big-endian format */
+  public char readChar() throws IOException {
+    int hi = ((int) readByte()) & 0xFF;
+    int lo = ((int) readByte()) & 0xFF;
+    return (char) ((hi << 8) | lo);
+  }
+
+  /** Reads binary data; one 32-bit unsigned int in big-endian format.
+      Returned as a long. */
+  public long readUnsignedInt() throws IOException {
+    long b1 = ((long) readByte()) & 0xFF;
+    long b2 = ((long) readByte()) & 0xFF;
+    long b3 = ((long) readByte()) & 0xFF;
+    long b4 = ((long) readByte()) & 0xFF;
+
+    return ((b1 << 24) | (b2 << 16) | (b3 << 8) | b4);
+  }
+
+  /** Reads binary data; a US-ASCII string of the specified length */
+  public String readByteString(int len) throws IOException {
+    byte[] b = new byte[len];
+    for (int i = 0; i < len; i++) {
+      b[i] = readByte();
+    }
+    try {
+      return new String(b, "US-ASCII");
+    }
+    catch (UnsupportedEncodingException e) {
+      throw new IOException(e.toString());
+    }
+  }
+
+  /** Reads binary data; a Unicode string of the specified length */
+  public String readCharString(int len) throws IOException {
+    char[] c = new char[len];
+    for (int i = 0; i < len; i++) {
+      c[i] = readChar();
+    }
+    return new String(c);
+  }
+
+  //----------------------------------------------------------------------
+  // Internals only below this point
+  //
+
+  private void skipWhitespace() throws IOException {
+    byte b;
+    while (Character.isWhitespace((char) (b = readByte()))) {
+    }
+    pushBack(b);
+  }
+
+  private boolean isHexDigit(char c) {
+    return (('0' <= c && c <= '9') ||
+            ('a' <= c && c <= 'f') ||
+            ('A' <= c && c <= 'F'));
+  }
+
+  private void pushBack(byte b) {
+    if (pushedBack) {
+      throw new InternalError("Only one character pushback supported");
+    }
+    backBuf = b;
+    pushedBack = true;
+  }
+
+  private byte readByteInternal() throws IOException {
+    int i = in.read();
+    if (i == -1) {
+      throw new IOException("End-of-file reached while reading from server");
+    }
+    return (byte) i;
+  }
+
+  private void error() throws IOException {
+    throw new IOException("Error parsing output of debug server");
+  }
+
+  private BufferedInputStream in;
+  private boolean pushedBack;
+  private byte backBuf;
+}