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Fixed BinaryStruct bit shifting issue

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This commit is contained in:
Ziver Koc 2016-05-12 23:00:28 +02:00
parent 3f21caa35b
commit 28d1f04246
3 changed files with 80 additions and 5 deletions
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2
src/zutil/ByteUtil.java
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@ -137,7 +137,7 @@ public class ByteUtil {
*/
public static byte[] shiftLeft(byte[] data, int shiftBy) {
if(0 > shiftBy || shiftBy > 8)
throw new IllegalArgumentException("Invalid shiftBy argument, allowed values: 0-8");
throw new IllegalArgumentException("Invalid shiftBy("+shiftBy+") argument, allowed values: 0-8");
if (shiftBy == 0)
return data;

8
src/zutil/parser/binary/BinaryStructInputStream.java
View file

@ -78,8 +78,7 @@ public class BinaryStructInputStream {
else {
byte[] valueData = new byte[(int) Math.ceil(field.getBitLength(struct) / 8.0)];
int fieldReadLength = 0; // How much we have read so far
int shiftBy = (dataBitIndex+1 + field.getBitLength(struct)) % 8;
int shiftBy = shiftBy(dataBitIndex, field.getBitLength(struct));
// Parse value
for (int valueDataIndex=valueData.length-1; valueDataIndex >= 0 ; --valueDataIndex) {
@ -102,5 +101,8 @@ public class BinaryStructInputStream {
return totalReadLength;
}
protected static int shiftBy(int bitIndex, int bitLength){
int shiftBy = (8 - ((7-bitIndex) + bitLength) % 8) % 8;
return shiftBy;
}
}

75
test/zutil/parser/binary/BinaryStructInputStreamTest.java
View file

@ -111,7 +111,6 @@ public class BinaryStructInputStreamTest {
struct.assertObj();
}
// TODO: add full non lined length support
@Test
public void nonLinedLength2(){
BinaryTestStruct struct = new BinaryTestStruct() {
@ -130,6 +129,33 @@ public class BinaryStructInputStreamTest {
struct.assertObj();
}
@Test
public void mixedType(){
BinaryTestStruct struct = new BinaryTestStruct() {
@BinaryField(index=1, length=4)
public int i1;
@BinaryField(index=2, length=1)
public boolean b2;
@BinaryField(index=3, length=1)
public boolean b3;
@BinaryField(index=4, length=1)
public boolean b4;
@BinaryField(index=5, length=1)
public boolean b5;
public void assertObj(){
assertEquals("i1", 6, i1);
assertEquals("b2", true, b2);
assertEquals("b3", true, b3);
assertEquals("b4", false, b4);
assertEquals("b5", true, b5);
}
};
BinaryStructInputStream.read(struct, new byte[]{0b0110_1101});
struct.assertObj();
}
@Test
public void customBinaryField(){
@ -175,4 +201,51 @@ public class BinaryStructInputStreamTest {
BinaryStructInputStream.read(struct, data);
struct.assertObj();
}
@Test
public void shiftBy(){
assertEquals(0, BinaryStructInputStream.shiftBy(0, 1));
assertEquals(1, BinaryStructInputStream.shiftBy(1, 1));
assertEquals(3, BinaryStructInputStream.shiftBy(3, 1));
assertEquals(4, BinaryStructInputStream.shiftBy(4, 1));
assertEquals(5, BinaryStructInputStream.shiftBy(5, 1));
assertEquals(6, BinaryStructInputStream.shiftBy(6, 1));
assertEquals(7, BinaryStructInputStream.shiftBy(7, 1));
assertEquals(0, BinaryStructInputStream.shiftBy(1, 2));
assertEquals(2, BinaryStructInputStream.shiftBy(3, 2));
assertEquals(6, BinaryStructInputStream.shiftBy(7, 2));
assertEquals(0, BinaryStructInputStream.shiftBy(7, 8));
assertEquals(2, BinaryStructInputStream.shiftBy(7, 6));
assertEquals(3, BinaryStructInputStream.shiftBy(7, 5));
assertEquals(6, BinaryStructInputStream.shiftBy(7, 2));
// Cross 1 byte border
assertEquals(7, BinaryStructInputStream.shiftBy(0, 2));
assertEquals(6, BinaryStructInputStream.shiftBy(1, 4));
assertEquals(4, BinaryStructInputStream.shiftBy(3, 8));
assertEquals(0, BinaryStructInputStream.shiftBy(3, 12));
assertEquals(0, BinaryStructInputStream.shiftBy(7, 16));
// Cross 2 byte borders
assertEquals(0, BinaryStructInputStream.shiftBy(7, 32));
assertEquals(7, BinaryStructInputStream.shiftBy(7, 33));
assertEquals(6, BinaryStructInputStream.shiftBy(7, 34));
assertEquals(5, BinaryStructInputStream.shiftBy(7, 35));
assertEquals(4, BinaryStructInputStream.shiftBy(7, 36));
assertEquals(3, BinaryStructInputStream.shiftBy(7, 37));
assertEquals(2, BinaryStructInputStream.shiftBy(7, 38));
assertEquals(1, BinaryStructInputStream.shiftBy(7, 39));
assertEquals(0, BinaryStructInputStream.shiftBy(7, 40));
assertEquals(7, BinaryStructInputStream.shiftBy(7, 41));
assertEquals(6, BinaryStructInputStream.shiftBy(6, 41));
assertEquals(5, BinaryStructInputStream.shiftBy(5, 41));
assertEquals(4, BinaryStructInputStream.shiftBy(4, 41));
assertEquals(3, BinaryStructInputStream.shiftBy(3, 41));
assertEquals(2, BinaryStructInputStream.shiftBy(2, 41));
assertEquals(1, BinaryStructInputStream.shiftBy(1, 41));
assertEquals(0, BinaryStructInputStream.shiftBy(7, 64));
}
}