Update variable length ints to accept negative values

src/main/kotlin/ru/dbotthepony/mc/otm/core/DataStreams.kt

@@ -7,6 +7,7 @@ import java.io.InputStream
 import java.io.OutputStream
 import java.util.*
 import java.util.function.Predicate
+import kotlin.math.absoluteValue
 
 interface IStreamCodec<V> {
 	fun read(stream: DataInputStream): V
@@ -134,59 +135,79 @@ fun OutputStream.writeDouble(value: Double) = writeLong(value.toBits())
 fun InputStream.readDouble() = Double.fromBits(readLong())
 
 fun InputStream.readVarIntLE(): Int {
+	val readFirst = read()
+
+	if (readFirst and 64 == 0) {
+		return if (readFirst and 128 != 0) -(readFirst and 63) else readFirst and 63
+	}
+
 	var result = 0
-	var read = read()
+	var nextBit = readFirst and 64
+	var read = readFirst and 63
 	var i = 0
 
-	while (read and 128 != 0) {
+	while (nextBit != 0) {
-		result = result or ((read and 127) shl i)
+		result = result or (read shl i)
 		read = read()
+		nextBit = read and 128
+		read = read and 127
+
+		if (i == 0)
+			i = 6
+		else
 			i += 7
 	}
 
-	result = result or ((read and 127) shl i)
+	result = result or (read shl i)
-
+	return if (readFirst and 128 != 0) -result else result
-	return result
 }
 
 fun OutputStream.writeVarIntLE(value: Int) {
-	require(value >= 0) { "Negative number provided: $value" }
+	write((if (value < 0) 128 else 0) or (if (value in -63 .. 63) 0 else 64) or (value.absoluteValue and 63))
-	var written = value
+	var written = value.absoluteValue ushr 6
 
-	while (written >= 128) {
+	while (written != 0) {
-		write((written and 127) or 128)
+		write((written and 127) or (if (written >= 128) 128 else 0))
 		written = written ushr 7
 	}
-
-	write(written)
 }
 
 fun InputStream.readVarLongLE(): Long {
+	val readFirst = read()
+
+	if (readFirst and 64 == 0) {
+		return if (readFirst and 128 != 0) -(readFirst and 63).toLong() else (readFirst and 63).toLong()
+	}
+
 	var result = 0L
-	var read = read()
+	var nextBit = readFirst and 64
+	var read = readFirst and 63
 	var i = 0
 
-	while (read and 128 != 0) {
+	while (nextBit != 0) {
-		result = result or ((read and 127) shl i).toLong()
+		result = result or (read shl i).toLong()
 		read = read()
+		nextBit = read and 128
+		read = read and 127
+
+		if (i == 0)
+			i = 6
+		else
 			i += 7
 	}
 
-	result = result or ((read and 127) shl i).toLong()
+	result = result or (read shl i).toLong()
-
+	return if (readFirst and 128 != 0) -result else result
-	return result
 }
 
 fun OutputStream.writeVarLongLE(value: Long) {
-	require(value >= 0L) { "Negative number provided: $value" }
+	write((if (value < 0L) 128 else 0) or (if (value in -63 .. 63) 0 else 64) or (value.absoluteValue and 63).toInt())
-	var written = value
+	var written = value.absoluteValue ushr 6
 
-	while (written >= 128) {
+	while (written != 0L) {
-		write(((written and 127) or 128).toInt())
+		write((written and 127).toInt() or (if (written >= 128) 128 else 0))
 		written = written ushr 7
 	}
-
-	write(written.toInt())
 }
 
 private data class IndexedStreamCodec<T>(

src/main/kotlin/ru/dbotthepony/mc/otm/network/FieldSynchronizer.kt

@@ -101,6 +101,14 @@ class FieldSynchronizer {
 		return Field(value, VarLongValueCodec, getter, setter)
 	}
 
+	fun fixedLong(
+		value: Long = 0L,
+		getter: FieldGetter<Long>? = null,
+		setter: FieldSetter<Long>? = null,
+	): Field<Long> {
+		return Field(value, LongValueCodec, getter, setter)
+	}
+
 	fun float(
 		value: Float = 0f,
 		getter: FieldGetter<Float>? = null,
@@ -133,6 +141,14 @@ class FieldSynchronizer {
 		return Field(value, VarIntValueCodec, getter, setter)
 	}
 
+	fun fixedInt(
+		value: Int = 0,
+		getter: FieldGetter<Int>? = null,
+		setter: FieldSetter<Int>? = null,
+	): Field<Int> {
+		return Field(value, IntValueCodec, getter, setter)
+	}
+
 	fun fraction(
 		value: ImpreciseFraction = ImpreciseFraction.ZERO,
 		getter: FieldGetter<ImpreciseFraction>? = null,

src/test/kotlin/ru/dbotthepony/mc/otm/tests/FriendlyStreams.kt

@@ -7,8 +7,10 @@ import org.junit.jupiter.api.DisplayName
 import org.junit.jupiter.api.Test
 import ru.dbotthepony.mc.otm.core.readInt
 import ru.dbotthepony.mc.otm.core.readVarIntLE
+import ru.dbotthepony.mc.otm.core.readVarLongLE
 import ru.dbotthepony.mc.otm.core.writeInt
 import ru.dbotthepony.mc.otm.core.writeVarIntLE
+import ru.dbotthepony.mc.otm.core.writeVarLongLE
 
 object FriendlyStreams {
 	@Test
@@ -32,22 +34,88 @@ object FriendlyStreams {
 		output.writeVarIntLE(10023)
 		output.writeVarIntLE(100000)
 
+		output.writeVarIntLE(-0)
+		output.writeVarIntLE(-1)
+		output.writeVarIntLE(-4)
+		output.writeVarIntLE(-15)
+		output.writeVarIntLE(-16)
+		output.writeVarIntLE(-127)
+		output.writeVarIntLE(-128)
+		output.writeVarIntLE(-129)
+		output.writeVarIntLE(-10023)
+		output.writeVarIntLE(-100000)
+
+		output.writeVarLongLE(0)
+		output.writeVarLongLE(1)
+		output.writeVarLongLE(4)
+		output.writeVarLongLE(15)
+		output.writeVarLongLE(16)
+		output.writeVarLongLE(127)
+		output.writeVarLongLE(128)
+		output.writeVarLongLE(129)
+		output.writeVarLongLE(10023)
+		output.writeVarLongLE(100000)
+
+		output.writeVarLongLE(-0)
+		output.writeVarLongLE(-1)
+		output.writeVarLongLE(-4)
+		output.writeVarLongLE(-15)
+		output.writeVarLongLE(-16)
+		output.writeVarLongLE(-127)
+		output.writeVarLongLE(-128)
+		output.writeVarLongLE(-129)
+		output.writeVarLongLE(-10023)
+		output.writeVarLongLE(-100000)
+
 		val input = FastByteArrayInputStream(output.array, 0, output.length)
 
-		assertEquals(input.readInt(), 4)
+		assertEquals(4, input.readInt())
-		assertEquals(input.readInt(), 16)
+		assertEquals(16, input.readInt())
-		assertEquals(input.readInt(), -1)
+		assertEquals(-1, input.readInt())
-		assertEquals(input.readInt(), 1000000)
+		assertEquals(1000000, input.readInt())
 
-		assertEquals(input.readVarIntLE(), 0)
+		assertEquals(0, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 1)
+		assertEquals(1, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 4)
+		assertEquals(4, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 15)
+		assertEquals(15, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 16)
+		assertEquals(16, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 127)
+		assertEquals(127, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 128)
+		assertEquals(128, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 129)
+		assertEquals(129, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 10023)
+		assertEquals(10023, input.readVarIntLE())
-		assertEquals(input.readVarIntLE(), 100000)
+		assertEquals(100000, input.readVarIntLE())
+
+		assertEquals(-0, input.readVarIntLE())
+		assertEquals(-1, input.readVarIntLE())
+		assertEquals(-4, input.readVarIntLE())
+		assertEquals(-15, input.readVarIntLE())
+		assertEquals(-16, input.readVarIntLE())
+		assertEquals(-127, input.readVarIntLE())
+		assertEquals(-128, input.readVarIntLE())
+		assertEquals(-129, input.readVarIntLE())
+		assertEquals(-10023, input.readVarIntLE())
+		assertEquals(-100000, input.readVarIntLE())
+
+		assertEquals(0, input.readVarLongLE())
+		assertEquals(1, input.readVarLongLE())
+		assertEquals(4, input.readVarLongLE())
+		assertEquals(15, input.readVarLongLE())
+		assertEquals(16, input.readVarLongLE())
+		assertEquals(127, input.readVarLongLE())
+		assertEquals(128, input.readVarLongLE())
+		assertEquals(129, input.readVarLongLE())
+		assertEquals(10023, input.readVarLongLE())
+		assertEquals(100000, input.readVarLongLE())
+
+		assertEquals(-0, input.readVarLongLE())
+		assertEquals(-1, input.readVarLongLE())
+		assertEquals(-4, input.readVarLongLE())
+		assertEquals(-15, input.readVarLongLE())
+		assertEquals(-16, input.readVarLongLE())
+		assertEquals(-127, input.readVarLongLE())
+		assertEquals(-128, input.readVarLongLE())
+		assertEquals(-129, input.readVarLongLE())
+		assertEquals(-10023, input.readVarLongLE())
+		assertEquals(-100000, input.readVarLongLE())
 	}
 }