| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.internal.util; |
| |
| import static com.android.internal.util.BitUtils.bytesToBEInt; |
| import static com.android.internal.util.BitUtils.bytesToLEInt; |
| import static com.android.internal.util.BitUtils.getUint16; |
| import static com.android.internal.util.BitUtils.getUint32; |
| import static com.android.internal.util.BitUtils.getUint8; |
| import static com.android.internal.util.BitUtils.packBits; |
| import static com.android.internal.util.BitUtils.uint16; |
| import static com.android.internal.util.BitUtils.uint32; |
| import static com.android.internal.util.BitUtils.uint8; |
| import static com.android.internal.util.BitUtils.unpackBits; |
| |
| import static org.junit.Assert.assertEquals; |
| import static org.junit.Assert.assertTrue; |
| |
| import androidx.test.filters.SmallTest; |
| import androidx.test.runner.AndroidJUnit4; |
| |
| import org.junit.Test; |
| import org.junit.runner.RunWith; |
| |
| import java.nio.ByteBuffer; |
| import java.util.Arrays; |
| import java.util.Random; |
| |
| @SmallTest |
| @RunWith(AndroidJUnit4.class) |
| public class BitUtilsTest { |
| |
| @Test |
| public void testUnsignedByteWideningConversions() { |
| byte b0 = 0; |
| byte b1 = 1; |
| byte bm1 = -1; |
| assertEquals(0, uint8(b0)); |
| assertEquals(1, uint8(b1)); |
| assertEquals(127, uint8(Byte.MAX_VALUE)); |
| assertEquals(128, uint8(Byte.MIN_VALUE)); |
| assertEquals(255, uint8(bm1)); |
| assertEquals(255, uint8((byte)255)); |
| } |
| |
| @Test |
| public void testUnsignedShortWideningConversions() { |
| short s0 = 0; |
| short s1 = 1; |
| short sm1 = -1; |
| assertEquals(0, uint16(s0)); |
| assertEquals(1, uint16(s1)); |
| assertEquals(32767, uint16(Short.MAX_VALUE)); |
| assertEquals(32768, uint16(Short.MIN_VALUE)); |
| assertEquals(65535, uint16(sm1)); |
| assertEquals(65535, uint16((short)65535)); |
| } |
| |
| @Test |
| public void testUnsignedShortComposition() { |
| byte b0 = 0; |
| byte b1 = 1; |
| byte b2 = 2; |
| byte b10 = 10; |
| byte b16 = 16; |
| byte b128 = -128; |
| byte b224 = -32; |
| byte b255 = -1; |
| assertEquals(0x0000, uint16(b0, b0)); |
| assertEquals(0xffff, uint16(b255, b255)); |
| assertEquals(0x0a01, uint16(b10, b1)); |
| assertEquals(0x8002, uint16(b128, b2)); |
| assertEquals(0x01ff, uint16(b1, b255)); |
| assertEquals(0x80ff, uint16(b128, b255)); |
| assertEquals(0xe010, uint16(b224, b16)); |
| } |
| |
| @Test |
| public void testUnsignedIntWideningConversions() { |
| assertEquals(0, uint32(0)); |
| assertEquals(1, uint32(1)); |
| assertEquals(2147483647L, uint32(Integer.MAX_VALUE)); |
| assertEquals(2147483648L, uint32(Integer.MIN_VALUE)); |
| assertEquals(4294967295L, uint32(-1)); |
| assertEquals(4294967295L, uint32((int)4294967295L)); |
| } |
| |
| @Test |
| public void testBytesToInt() { |
| assertEquals(0x00000000, bytesToBEInt(bytes(0, 0, 0, 0))); |
| assertEquals(0xffffffff, bytesToBEInt(bytes(255, 255, 255, 255))); |
| assertEquals(0x0a000001, bytesToBEInt(bytes(10, 0, 0, 1))); |
| assertEquals(0x0a000002, bytesToBEInt(bytes(10, 0, 0, 2))); |
| assertEquals(0x0a001fff, bytesToBEInt(bytes(10, 0, 31, 255))); |
| assertEquals(0xe0000001, bytesToBEInt(bytes(224, 0, 0, 1))); |
| |
| assertEquals(0x00000000, bytesToLEInt(bytes(0, 0, 0, 0))); |
| assertEquals(0x01020304, bytesToLEInt(bytes(4, 3, 2, 1))); |
| assertEquals(0xffff0000, bytesToLEInt(bytes(0, 0, 255, 255))); |
| } |
| |
| @Test |
| public void testUnsignedGetters() { |
| ByteBuffer b = ByteBuffer.allocate(4); |
| b.putInt(0xffff); |
| |
| assertEquals(0x0, getUint8(b, 0)); |
| assertEquals(0x0, getUint8(b, 1)); |
| assertEquals(0xff, getUint8(b, 2)); |
| assertEquals(0xff, getUint8(b, 3)); |
| |
| assertEquals(0x0, getUint16(b, 0)); |
| assertEquals(0xffff, getUint16(b, 2)); |
| |
| b.rewind(); |
| b.putInt(0xffffffff); |
| assertEquals(0xffffffffL, getUint32(b, 0)); |
| } |
| |
| @Test |
| public void testBitsPacking() { |
| BitPackingTestCase[] testCases = { |
| new BitPackingTestCase(0, ints()), |
| new BitPackingTestCase(1, ints(0)), |
| new BitPackingTestCase(2, ints(1)), |
| new BitPackingTestCase(3, ints(0, 1)), |
| new BitPackingTestCase(4, ints(2)), |
| new BitPackingTestCase(6, ints(1, 2)), |
| new BitPackingTestCase(9, ints(0, 3)), |
| new BitPackingTestCase(~Long.MAX_VALUE, ints(63)), |
| new BitPackingTestCase(~Long.MAX_VALUE + 1, ints(0, 63)), |
| new BitPackingTestCase(~Long.MAX_VALUE + 2, ints(1, 63)), |
| }; |
| for (BitPackingTestCase tc : testCases) { |
| int[] got = unpackBits(tc.packedBits); |
| assertTrue( |
| "unpackBits(" |
| + tc.packedBits |
| + "): expected " |
| + Arrays.toString(tc.bits) |
| + " but got " |
| + Arrays.toString(got), |
| Arrays.equals(tc.bits, got)); |
| } |
| for (BitPackingTestCase tc : testCases) { |
| long got = packBits(tc.bits); |
| assertEquals( |
| "packBits(" |
| + Arrays.toString(tc.bits) |
| + "): expected " |
| + tc.packedBits |
| + " but got " |
| + got, |
| tc.packedBits, |
| got); |
| } |
| |
| long[] moreTestCases = { |
| 0, 1, -1, 23895, -908235, Long.MAX_VALUE, Long.MIN_VALUE, new Random().nextLong(), |
| }; |
| for (long l : moreTestCases) { |
| assertEquals(l, packBits(unpackBits(l))); |
| } |
| } |
| |
| static byte[] bytes(int b1, int b2, int b3, int b4) { |
| return new byte[] {b(b1), b(b2), b(b3), b(b4)}; |
| } |
| |
| static byte b(int i) { |
| return (byte) i; |
| } |
| |
| static int[] ints(int... array) { |
| return array; |
| } |
| |
| static class BitPackingTestCase { |
| final int[] bits; |
| final long packedBits; |
| |
| BitPackingTestCase(long packedBits, int[] bits) { |
| this.bits = bits; |
| this.packedBits = packedBits; |
| } |
| } |
| } |