| /* |
| * Copyright (c) 2000, 2002, 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle 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 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.nio.ch; // Formerly in sun.misc |
| |
| import java.nio.ByteOrder; |
| import sun.misc.Unsafe; |
| |
| |
| // ## In the fullness of time, this class will be eliminated |
| |
| /** |
| * Proxies for objects that reside in native memory. |
| */ |
| |
| class NativeObject { // package-private |
| |
| protected static final Unsafe unsafe = Unsafe.getUnsafe(); |
| |
| // Native allocation address; |
| // may be smaller than the base address due to page-size rounding |
| // |
| protected long allocationAddress; |
| |
| // Native base address |
| // |
| private final long address; |
| |
| /** |
| * Creates a new native object that is based at the given native address. |
| */ |
| NativeObject(long address) { |
| this.allocationAddress = address; |
| this.address = address; |
| } |
| |
| /** |
| * Creates a new native object allocated at the given native address but |
| * whose base is at the additional offset. |
| */ |
| NativeObject(long address, long offset) { |
| this.allocationAddress = address; |
| this.address = address + offset; |
| } |
| |
| // Invoked only by AllocatedNativeObject |
| // |
| protected NativeObject(int size, boolean pageAligned) { |
| if (!pageAligned) { |
| this.allocationAddress = unsafe.allocateMemory(size); |
| this.address = this.allocationAddress; |
| } else { |
| int ps = pageSize(); |
| long a = unsafe.allocateMemory(size + ps); |
| this.allocationAddress = a; |
| this.address = a + ps - (a & (ps - 1)); |
| } |
| } |
| |
| /** |
| * Returns the native base address of this native object. |
| * |
| * @return The native base address |
| */ |
| long address() { |
| return address; |
| } |
| |
| long allocationAddress() { |
| return allocationAddress; |
| } |
| |
| /** |
| * Creates a new native object starting at the given offset from the base |
| * of this native object. |
| * |
| * @param offset |
| * The offset from the base of this native object that is to be |
| * the base of the new native object |
| * |
| * @return The newly created native object |
| */ |
| NativeObject subObject(int offset) { |
| return new NativeObject(offset + address); |
| } |
| |
| /** |
| * Reads an address from this native object at the given offset and |
| * constructs a native object using that address. |
| * |
| * @param offset |
| * The offset of the address to be read. Note that the size of an |
| * address is implementation-dependent. |
| * |
| * @return The native object created using the address read from the |
| * given offset |
| */ |
| NativeObject getObject(int offset) { |
| long newAddress = 0L; |
| switch (addressSize()) { |
| case 8: |
| newAddress = unsafe.getLong(offset + address); |
| break; |
| case 4: |
| newAddress = unsafe.getInt(offset + address) & 0x00000000FFFFFFFF; |
| break; |
| default: |
| throw new InternalError("Address size not supported"); |
| } |
| |
| return new NativeObject(newAddress); |
| } |
| |
| /** |
| * Writes the base address of the given native object at the given offset |
| * of this native object. |
| * |
| * @param offset |
| * The offset at which the address is to be written. Note that the |
| * size of an address is implementation-dependent. |
| * |
| * @param ob |
| * The native object whose address is to be written |
| */ |
| void putObject(int offset, NativeObject ob) { |
| switch (addressSize()) { |
| case 8: |
| putLong(offset, ob.address); |
| break; |
| case 4: |
| putInt(offset, (int)(ob.address & 0x00000000FFFFFFFF)); |
| break; |
| default: |
| throw new InternalError("Address size not supported"); |
| } |
| } |
| |
| |
| /* -- Value accessors: No range checking! -- */ |
| |
| /** |
| * Reads a byte starting at the given offset from base of this native |
| * object. |
| * |
| * @param offset |
| * The offset at which to read the byte |
| * |
| * @return The byte value read |
| */ |
| final byte getByte(int offset) { |
| return unsafe.getByte(offset + address); |
| } |
| |
| /** |
| * Writes a byte at the specified offset from this native object's |
| * base address. |
| * |
| * @param offset |
| * The offset at which to write the byte |
| * |
| * @param value |
| * The byte value to be written |
| */ |
| final void putByte(int offset, byte value) { |
| unsafe.putByte(offset + address, value); |
| } |
| |
| /** |
| * Reads a short starting at the given offset from base of this native |
| * object. |
| * |
| * @param offset |
| * The offset at which to read the short |
| * |
| * @return The short value read |
| */ |
| final short getShort(int offset) { |
| return unsafe.getShort(offset + address); |
| } |
| |
| /** |
| * Writes a short at the specified offset from this native object's |
| * base address. |
| * |
| * @param offset |
| * The offset at which to write the short |
| * |
| * @param value |
| * The short value to be written |
| */ |
| final void putShort(int offset, short value) { |
| unsafe.putShort(offset + address, value); |
| } |
| |
| /** |
| * Reads a char starting at the given offset from base of this native |
| * object. |
| * |
| * @param offset |
| * The offset at which to read the char |
| * |
| * @return The char value read |
| */ |
| final char getChar(int offset) { |
| return unsafe.getChar(offset + address); |
| } |
| |
| /** |
| * Writes a char at the specified offset from this native object's |
| * base address. |
| * |
| * @param offset |
| * The offset at which to write the char |
| * |
| * @param value |
| * The char value to be written |
| */ |
| final void putChar(int offset, char value) { |
| unsafe.putChar(offset + address, value); |
| } |
| |
| /** |
| * Reads an int starting at the given offset from base of this native |
| * object. |
| * |
| * @param offset |
| * The offset at which to read the int |
| * |
| * @return The int value read |
| */ |
| final int getInt(int offset) { |
| return unsafe.getInt(offset + address); |
| } |
| |
| /** |
| * Writes an int at the specified offset from this native object's |
| * base address. |
| * |
| * @param offset |
| * The offset at which to write the int |
| * |
| * @param value |
| * The int value to be written |
| */ |
| final void putInt(int offset, int value) { |
| unsafe.putInt(offset + address, value); |
| } |
| |
| /** |
| * Reads a long starting at the given offset from base of this native |
| * object. |
| * |
| * @param offset |
| * The offset at which to read the long |
| * |
| * @return The long value read |
| */ |
| final long getLong(int offset) { |
| return unsafe.getLong(offset + address); |
| } |
| |
| /** |
| * Writes a long at the specified offset from this native object's |
| * base address. |
| * |
| * @param offset |
| * The offset at which to write the long |
| * |
| * @param value |
| * The long value to be written |
| */ |
| final void putLong(int offset, long value) { |
| unsafe.putLong(offset + address, value); |
| } |
| |
| /** |
| * Reads a float starting at the given offset from base of this native |
| * object. |
| * |
| * @param offset |
| * The offset at which to read the float |
| * |
| * @return The float value read |
| */ |
| final float getFloat(int offset) { |
| return unsafe.getFloat(offset + address); |
| } |
| |
| /** |
| * Writes a float at the specified offset from this native object's |
| * base address. |
| * |
| * @param offset |
| * The offset at which to write the float |
| * |
| * @param value |
| * The float value to be written |
| */ |
| final void putFloat(int offset, float value) { |
| unsafe.putFloat(offset + address, value); |
| } |
| |
| /** |
| * Reads a double starting at the given offset from base of this native |
| * object. |
| * |
| * @param offset |
| * The offset at which to read the double |
| * |
| * @return The double value read |
| */ |
| final double getDouble(int offset) { |
| return unsafe.getDouble(offset + address); |
| } |
| |
| /** |
| * Writes a double at the specified offset from this native object's |
| * base address. |
| * |
| * @param offset |
| * The offset at which to write the double |
| * |
| * @param value |
| * The double value to be written |
| */ |
| final void putDouble(int offset, double value) { |
| unsafe.putDouble(offset + address, value); |
| } |
| |
| /** |
| * Returns the native architecture's address size in bytes. |
| * |
| * @return The address size of the native architecture |
| */ |
| static int addressSize() { |
| return unsafe.addressSize(); |
| } |
| |
| // Cache for byte order |
| private static ByteOrder byteOrder = null; |
| |
| /** |
| * Returns the byte order of the underlying hardware. |
| * |
| * @return An instance of {@link java.nio.ByteOrder} |
| */ |
| static ByteOrder byteOrder() { |
| if (byteOrder != null) |
| return byteOrder; |
| long a = unsafe.allocateMemory(8); |
| try { |
| unsafe.putLong(a, 0x0102030405060708L); |
| byte b = unsafe.getByte(a); |
| switch (b) { |
| case 0x01: byteOrder = ByteOrder.BIG_ENDIAN; break; |
| case 0x08: byteOrder = ByteOrder.LITTLE_ENDIAN; break; |
| default: |
| assert false; |
| } |
| } finally { |
| unsafe.freeMemory(a); |
| } |
| return byteOrder; |
| } |
| |
| // Cache for page size |
| private static int pageSize = -1; |
| |
| /** |
| * Returns the page size of the underlying hardware. |
| * |
| * @return The page size, in bytes |
| */ |
| static int pageSize() { |
| if (pageSize == -1) |
| pageSize = unsafe.pageSize(); |
| return pageSize; |
| } |
| |
| } |