1 /*
2 * Copyright 2018 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty.channel.unix;
17
18 import io.netty.util.internal.PlatformDependent;
19 import io.netty.util.internal.UnstableApi;
20
21 import java.nio.ByteBuffer;
22 import java.nio.ByteOrder;
23
24 @UnstableApi
25 public final class Buffer {
26
27 private Buffer() { }
28
29 /**
30 * Free the direct {@link ByteBuffer}.
31 */
32 public static void free(ByteBuffer buffer) {
33 PlatformDependent.freeDirectBuffer(buffer);
34 }
35
36 /**
37 * Returns a new {@link ByteBuffer} which has the same {@link ByteOrder} as the native order of the machine.
38 */
39 public static ByteBuffer allocateDirectWithNativeOrder(int capacity) {
40 return ByteBuffer.allocateDirect(capacity).order(
41 PlatformDependent.BIG_ENDIAN_NATIVE_ORDER ? ByteOrder.BIG_ENDIAN : ByteOrder.LITTLE_ENDIAN);
42 }
43
44 /**
45 * Returns the memory address of the given direct {@link ByteBuffer}.
46 */
47 public static long memoryAddress(ByteBuffer buffer) {
48 assert buffer.isDirect();
49 if (PlatformDependent.hasUnsafe()) {
50 return PlatformDependent.directBufferAddress(buffer);
51 }
52 return memoryAddress0(buffer);
53 }
54
55 /**
56 * Returns the size of a pointer.
57 */
58 public static int addressSize() {
59 if (PlatformDependent.hasUnsafe()) {
60 return PlatformDependent.addressSize();
61 }
62 return addressSize0();
63 }
64
65 // If Unsafe can not be used we will need to do JNI calls.
66 private static native int addressSize0();
67 private static native long memoryAddress0(ByteBuffer buffer);
68 }