/*
* Copyright 2003-2004 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. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* 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.awt;
import java.awt.Color;
import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;
/**
* Per-screen XSETTINGS.
*/
public class XSettings {
/**
*/
private long serial = -1;
/**
* Update these settings with <code>data</code> obtained from
* XSETTINGS manager.
*
* @param data settings data obtained from
* <code>_XSETTINGS_SETTINGS</code> window property of the
* settings manager.
* @return a <code>Map</code> of changed settings.
*/
public Map update(byte[] data) {
return (new Update(data)).update();
}
/**
* TBS ...
*/
class Update {
/* byte order mark */
private static final int LITTLE_ENDIAN = 0;
private static final int BIG_ENDIAN = 1;
/* setting type */
private static final int TYPE_INTEGER = 0;
private static final int TYPE_STRING = 1;
private static final int TYPE_COLOR = 2;
private byte[] data;
private int dlen;
private int idx;
private boolean isLittle;
private long serial = -1;
private int nsettings = 0;
private boolean isValid;
private HashMap updatedSettings;
/**
* Construct an Update object for the data read from
* <code>_XSETTINGS_SETTINGS</code> property of the XSETTINGS
* selection owner.
*
* @param data <code>_XSETTINGS_SETTINGS</code> contents.
*/
Update(byte[] data) {
this.data = data;
dlen = data.length;
if (dlen < 12) {
// XXX: debug trace?
return;
}
// first byte gives endianness of the data
// next 3 bytes are unused (pad to 32 bit)
idx = 0;
isLittle = (getCARD8() == LITTLE_ENDIAN);
idx = 4;
serial = getCARD32();
// N_SETTINGS is actually CARD32 (i.e. unsigned), but
// since java doesn't have an unsigned int type, and
// N_SETTINGS cannot realistically exceed 2^31 (so we
// gonna use int anyway), just read it as INT32.
idx = 8;
nsettings = getINT32();
updatedSettings = new HashMap();
isValid = true;
}
private void needBytes(int n)
throws IndexOutOfBoundsException
{
if (idx + n <= dlen) {
return;
}
throw new IndexOutOfBoundsException("at " + idx
+ " need " + n
+ " length " + dlen);
}
private int getCARD8()
throws IndexOutOfBoundsException
{
needBytes(1);
int val = data[idx] & 0xff;
++idx;
return val;
}
private int getCARD16()
throws IndexOutOfBoundsException
{
needBytes(2);
int val;
if (isLittle) {
val = ((data[idx + 0] & 0xff) )
| ((data[idx + 1] & 0xff) << 8);
} else {
val = ((data[idx + 0] & 0xff) << 8)
| ((data[idx + 1] & 0xff) );
}
idx += 2;
return val;
}
private int getINT32()
throws IndexOutOfBoundsException
{
needBytes(4);
int val;
if (isLittle) {
val = ((data[idx + 0] & 0xff) )
| ((data[idx + 1] & 0xff) << 8)
| ((data[idx + 2] & 0xff) << 16)
| ((data[idx + 3] & 0xff) << 24);
} else {
val = ((data[idx + 0] & 0xff) << 24)
| ((data[idx + 1] & 0xff) << 16)
| ((data[idx + 2] & 0xff) << 8)
| ((data[idx + 3] & 0xff) << 0);
}
idx += 4;
return val;
}
private long getCARD32()
throws IndexOutOfBoundsException
{
return getINT32() & 0x00000000ffffffffL;
}
private String getString(int len)
throws IndexOutOfBoundsException
{
needBytes(len);
String str = null;
try {
str = new String(data, idx, len, "UTF-8");
} catch (UnsupportedEncodingException e) {
// XXX: cannot happen, "UTF-8" is always supported
}
idx = (idx + len + 3) & ~0x3;
return str;
}
/**
* Update settings.
*/
public Map update() {
if (!isValid) {
return null;
}
synchronized (XSettings.this) {
long currentSerial = XSettings.this.serial;
if (this.serial <= currentSerial) {
return null;
}
for (int i = 0; i < nsettings && idx < dlen; ++i) {
updateOne(currentSerial);
}
XSettings.this.serial = this.serial;
}
return updatedSettings;
}
/**
* Parses a particular x setting.
*
* @exception IndexOutOfBoundsException if there isn't enough
* data for a setting.
*/
private void updateOne(long currentSerial)
throws IndexOutOfBoundsException,
IllegalArgumentException
{
int type = getCARD8();
++idx; // pad to next CARD16
// save position of the property name, skip to serial
int nameLen = getCARD16();
int nameIdx = idx;
// check if we should bother
idx = (idx + nameLen + 3) & ~0x3; // pad to 32 bit
long lastChanged = getCARD32();
// Avoid constructing garbage for properties that has not
// changed, skip the data for this property.
if (lastChanged <= currentSerial) { // skip
if (type == TYPE_INTEGER) {
idx += 4;
} else if (type == TYPE_STRING) {
int len = getINT32();
idx = (idx + len + 3) & ~0x3;
} else if (type == TYPE_COLOR) {
idx += 8; // 4 CARD16
} else {
throw new IllegalArgumentException("Unknown type: "
+ type);
}
return;
}
idx = nameIdx;
String name = getString(nameLen);
idx += 4; // skip serial, parsed above
Object value = null;
if (type == TYPE_INTEGER) {
value = Integer.valueOf(getINT32());
}
else if (type == TYPE_STRING) {
value = getString(getINT32());
}
else if (type == TYPE_COLOR) {
int r = getCARD16();
int g = getCARD16();
int b = getCARD16();
int a = getCARD16();
value = new Color(r / 65535.0f,
g / 65535.0f,
b / 65535.0f,
a / 65535.0f);
}
else {
throw new IllegalArgumentException("Unknown type: " + type);
}
if (name == null) {
// dtrace???
return;
}
updatedSettings.put(name, value);
}
} // class XSettings.Update
}
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