/*
* Copyright (c) 2000, 2005, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
package sun.jvm.hotspot.code;
import sun.jvm.hotspot.debugger.*;
public class CompressedReadStream extends CompressedStream {
/** Equivalent to CompressedReadStream(buffer, 0) */
public CompressedReadStream(Address buffer) {
this(buffer, 0);
}
public CompressedReadStream(Address buffer, int position) {
super(buffer, position);
}
public boolean readBoolean() {
return (read() != 0);
}
public byte readByte() {
return (byte) read();
}
public char readChar() {
return (char) readInt();
}
public short readShort() {
return (short) readSignedInt();
}
public int readSignedInt() {
return decodeSign(readInt());
}
public int readInt() {
int b0 = read();
if (b0 < L) {
return b0;
} else {
return readIntMb(b0);
}
}
public float readFloat() {
return Float.intBitsToFloat(reverseInt(readInt()));
}
public double readDouble() {
int rh = readInt();
int rl = readInt();
int h = reverseInt(rh);
int l = reverseInt(rl);
return Double.longBitsToDouble((h << 32) | ((long)l & 0x00000000FFFFFFFFL));
}
public long readLong() {
long low = readSignedInt() & 0x00000000FFFFFFFFL;
long high = readSignedInt();
return (high << 32) | low;
}
//--------------------------------------------------------------------------------
// Internals only below this point
//
// This encoding, called UNSIGNED5, is taken from J2SE Pack200.
// It assumes that most values have lots of leading zeroes.
// Very small values, in the range [0..191], code in one byte.
// Any 32-bit value (including negatives) can be coded, in
// up to five bytes. The grammar is:
// low_byte = [0..191]
// high_byte = [192..255]
// any_byte = low_byte | high_byte
// coding = low_byte
// | high_byte low_byte
// | high_byte high_byte low_byte
// | high_byte high_byte high_byte low_byte
// | high_byte high_byte high_byte high_byte any_byte
// Each high_byte contributes six bits of payload.
// The encoding is one-to-one (except for integer overflow)
// and easy to parse and unparse.
private int readIntMb(int b0) {
int pos = position - 1;
int sum = b0;
// must collect more bytes: b[1]...b[4]
int lg_H_i = lg_H;
for (int i = 0; ;) {
int b_i = read(pos + (++i));
sum += b_i << lg_H_i; // sum += b[i]*(64**i)
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