using System; using System.Collections.Generic; using System.IO; using System.Text; using UnityEngine; namespace Mirror { /// Helper class that weaver populates with all reader types. // Note that c# creates a different static variable for each type // -> Weaver.ReaderWriterProcessor.InitializeReaderAndWriters() populates it public static class Reader { public static Func read; } /// Network Reader for most simple types like floats, ints, buffers, structs, etc. Use NetworkReaderPool.GetReader() to avoid allocations. // Note: This class is intended to be extremely pedantic, // and throw exceptions whenever stuff is going slightly wrong. // The exceptions will be handled in NetworkServer/NetworkClient. public class NetworkReader { // internal buffer // byte[] pointer would work, but we use ArraySegment to also support // the ArraySegment constructor ArraySegment buffer; /// Next position to read from the buffer // 'int' is the best type for .Position. 'short' is too small if we send >32kb which would result in negative .Position // -> converting long to int is fine until 2GB of data (MAX_INT), so we don't have to worry about overflows here public int Position; /// Total number of bytes to read from buffer public int Length => buffer.Count; /// Remaining bytes that can be read, for convenience. public int Remaining => Length - Position; public NetworkReader(byte[] bytes) { buffer = new ArraySegment(bytes); } public NetworkReader(ArraySegment segment) { buffer = segment; } // sometimes it's useful to point a reader on another buffer instead of // allocating a new reader (e.g. NetworkReaderPool) public void SetBuffer(byte[] bytes) { buffer = new ArraySegment(bytes); Position = 0; } public void SetBuffer(ArraySegment segment) { buffer = segment; Position = 0; } public byte ReadByte() { if (Position + 1 > buffer.Count) { throw new EndOfStreamException("ReadByte out of range:" + ToString()); } return buffer.Array[buffer.Offset + Position++]; } /// Read 'count' bytes into the bytes array // TODO why does this also return bytes[]??? public byte[] ReadBytes(byte[] bytes, int count) { // check if passed byte array is big enough if (count > bytes.Length) { throw new EndOfStreamException("ReadBytes can't read " + count + " + bytes because the passed byte[] only has length " + bytes.Length); } ArraySegment data = ReadBytesSegment(count); Array.Copy(data.Array, data.Offset, bytes, 0, count); return bytes; } /// Read 'count' bytes allocation-free as ArraySegment that points to the internal array. public ArraySegment ReadBytesSegment(int count) { // check if within buffer limits if (Position + count > buffer.Count) { throw new EndOfStreamException("ReadBytesSegment can't read " + count + " bytes because it would read past the end of the stream. " + ToString()); } // return the segment ArraySegment result = new ArraySegment(buffer.Array, buffer.Offset + Position, count); Position += count; return result; } public override string ToString() { return $"NetworkReader pos={Position} len={Length} buffer={BitConverter.ToString(buffer.Array, buffer.Offset, buffer.Count)}"; } /// Reads any data type that mirror supports. Uses weaver populated Reader(T).read public T Read() { Func readerDelegate = Reader.read; if (readerDelegate == null) { Debug.LogError($"No reader found for {typeof(T)}. Use a type supported by Mirror or define a custom reader"); return default; } return readerDelegate(this); } } // Mirror's Weaver automatically detects all NetworkReader function types, // but they do all need to be extensions. public static class NetworkReaderExtensions { // cache encoding instead of creating it each time // 1000 readers before: 1MB GC, 30ms // 1000 readers after: 0.8MB GC, 18ms static readonly UTF8Encoding encoding = new UTF8Encoding(false, true); public static byte ReadByte(this NetworkReader reader) => reader.ReadByte(); public static sbyte ReadSByte(this NetworkReader reader) => (sbyte)reader.ReadByte(); public static char ReadChar(this NetworkReader reader) => (char)reader.ReadUShort(); // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadBool instead.")] public static bool ReadBoolean(this NetworkReader reader) => reader.ReadBool(); public static bool ReadBool(this NetworkReader reader) => reader.ReadByte() != 0; // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadShort instead.")] public static short ReadInt16(this NetworkReader reader) => reader.ReadShort(); public static short ReadShort(this NetworkReader reader) => (short)reader.ReadUShort(); // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadUShort instead.")] public static ushort ReadUInt16(this NetworkReader reader) => reader.ReadUShort(); public static ushort ReadUShort(this NetworkReader reader) { ushort value = 0; value |= reader.ReadByte(); value |= (ushort)(reader.ReadByte() << 8); return value; } // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadInt instead.")] public static int ReadInt32(this NetworkReader reader) => reader.ReadInt(); public static int ReadInt(this NetworkReader reader) => (int)reader.ReadUInt(); // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadUInt instead.")] public static uint ReadUInt32(this NetworkReader reader) => reader.ReadUInt(); public static uint ReadUInt(this NetworkReader reader) { uint value = 0; value |= reader.ReadByte(); value |= (uint)(reader.ReadByte() << 8); value |= (uint)(reader.ReadByte() << 16); value |= (uint)(reader.ReadByte() << 24); return value; } // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadLong instead.")] public static long ReadInt64(this NetworkReader reader) => reader.ReadLong(); public static long ReadLong(this NetworkReader reader) => (long)reader.ReadULong(); // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadULong instead.")] public static ulong ReadUInt64(this NetworkReader reader) => reader.ReadULong(); public static ulong ReadULong(this NetworkReader reader) { ulong value = 0; value |= reader.ReadByte(); value |= ((ulong)reader.ReadByte()) << 8; value |= ((ulong)reader.ReadByte()) << 16; value |= ((ulong)reader.ReadByte()) << 24; value |= ((ulong)reader.ReadByte()) << 32; value |= ((ulong)reader.ReadByte()) << 40; value |= ((ulong)reader.ReadByte()) << 48; value |= ((ulong)reader.ReadByte()) << 56; return value; } // Deprecated 2021-05-18 [Obsolete("We've cleaned up the API. Use ReadFloat instead.")] public static float ReadSingle(this NetworkReader reader) => reader.ReadFloat(); public static float ReadFloat(this NetworkReader reader) { UIntFloat converter = new UIntFloat(); converter.intValue = reader.ReadUInt(); return converter.floatValue; } public static double ReadDouble(this NetworkReader reader) { UIntDouble converter = new UIntDouble(); converter.longValue = reader.ReadULong(); return converter.doubleValue; } public static decimal ReadDecimal(this NetworkReader reader) { UIntDecimal converter = new UIntDecimal(); converter.longValue1 = reader.ReadULong(); converter.longValue2 = reader.ReadULong(); return converter.decimalValue; } /// if an invalid utf8 string is sent public static string ReadString(this NetworkReader reader) { // read number of bytes ushort size = reader.ReadUShort(); // null support, see NetworkWriter if (size == 0) return null; int realSize = size - 1; // make sure it's within limits to avoid allocation attacks etc. if (realSize >= NetworkWriter.MaxStringLength) { throw new EndOfStreamException("ReadString too long: " + realSize + ". Limit is: " + NetworkWriter.MaxStringLength); } ArraySegment data = reader.ReadBytesSegment(realSize); // convert directly from buffer to string via encoding return encoding.GetString(data.Array, data.Offset, data.Count); } /// if count is invalid public static byte[] ReadBytesAndSize(this NetworkReader reader) { // count = 0 means the array was null // otherwise count -1 is the length of the array uint count = reader.ReadUInt(); // Use checked() to force it to throw OverflowException if data is invalid return count == 0 ? null : reader.ReadBytes(checked((int)(count - 1u))); } /// if count is invalid public static ArraySegment ReadBytesAndSizeSegment(this NetworkReader reader) { // count = 0 means the array was null // otherwise count - 1 is the length of the array uint count = reader.ReadUInt(); // Use checked() to force it to throw OverflowException if data is invalid return count == 0 ? default : reader.ReadBytesSegment(checked((int)(count - 1u))); } public static Vector2 ReadVector2(this NetworkReader reader) => new Vector2(reader.ReadFloat(), reader.ReadFloat()); public static Vector3 ReadVector3(this NetworkReader reader) => new Vector3(reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat()); // TODO add nullable support to weaver instead public static Vector3? ReadVector3Nullable(this NetworkReader reader) => reader.ReadBool() ? ReadVector3(reader) : default; public static Vector4 ReadVector4(this NetworkReader reader) => new Vector4(reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat()); public static Vector2Int ReadVector2Int(this NetworkReader reader) => new Vector2Int(reader.ReadInt(), reader.ReadInt()); public static Vector3Int ReadVector3Int(this NetworkReader reader) => new Vector3Int(reader.ReadInt(), reader.ReadInt(), reader.ReadInt()); public static Color ReadColor(this NetworkReader reader) => new Color(reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat()); public static Color32 ReadColor32(this NetworkReader reader) => new Color32(reader.ReadByte(), reader.ReadByte(), reader.ReadByte(), reader.ReadByte()); public static Quaternion ReadQuaternion(this NetworkReader reader) => new Quaternion(reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat()); // TODO add nullable support to weaver instead public static Quaternion? ReadQuaternionNullable(this NetworkReader reader) => reader.ReadBool() ? ReadQuaternion(reader) : default; public static Rect ReadRect(this NetworkReader reader) => new Rect(reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat(), reader.ReadFloat()); public static Plane ReadPlane(this NetworkReader reader) => new Plane(reader.ReadVector3(), reader.ReadFloat()); public static Ray ReadRay(this NetworkReader reader) => new Ray(reader.ReadVector3(), reader.ReadVector3()); public static Matrix4x4 ReadMatrix4x4(this NetworkReader reader) { return new Matrix4x4 { m00 = reader.ReadFloat(), m01 = reader.ReadFloat(), m02 = reader.ReadFloat(), m03 = reader.ReadFloat(), m10 = reader.ReadFloat(), m11 = reader.ReadFloat(), m12 = reader.ReadFloat(), m13 = reader.ReadFloat(), m20 = reader.ReadFloat(), m21 = reader.ReadFloat(), m22 = reader.ReadFloat(), m23 = reader.ReadFloat(), m30 = reader.ReadFloat(), m31 = reader.ReadFloat(), m32 = reader.ReadFloat(), m33 = reader.ReadFloat() }; } public static byte[] ReadBytes(this NetworkReader reader, int count) { byte[] bytes = new byte[count]; reader.ReadBytes(bytes, count); return bytes; } public static Guid ReadGuid(this NetworkReader reader) => new Guid(reader.ReadBytes(16)); public static Transform ReadTransform(this NetworkReader reader) { // Don't use null propagation here as it could lead to MissingReferenceException NetworkIdentity networkIdentity = reader.ReadNetworkIdentity(); return networkIdentity != null ? networkIdentity.transform : null; } public static GameObject ReadGameObject(this NetworkReader reader) { // Don't use null propagation here as it could lead to MissingReferenceException NetworkIdentity networkIdentity = reader.ReadNetworkIdentity(); return networkIdentity != null ? networkIdentity.gameObject : null; } public static NetworkIdentity ReadNetworkIdentity(this NetworkReader reader) { uint netId = reader.ReadUInt(); if (netId == 0) return null; if (NetworkIdentity.spawned.TryGetValue(netId, out NetworkIdentity identity)) { return identity; } // a netId not being in spawned is common. // for example, "[SyncVar] NetworkIdentity target" netId would not // be known on client if the monster walks out of proximity for a // moment. no need to log any error or warning here. return null; } public static NetworkBehaviour ReadNetworkBehaviour(this NetworkReader reader) { uint netId = reader.ReadUInt(); if (netId == 0) return null; // if netId is not 0, then index is also sent to read before returning byte componentIndex = reader.ReadByte(); if (NetworkIdentity.spawned.TryGetValue(netId, out NetworkIdentity identity)) { return identity.NetworkBehaviours[componentIndex]; } // a netId not being in spawned is common. // for example, "[SyncVar] NetworkBehaviour target" netId would not // be known on client if the monster walks out of proximity for a // moment. no need to log any error or warning here. return null; } public static T ReadNetworkBehaviour(this NetworkReader reader) where T : NetworkBehaviour { return reader.ReadNetworkBehaviour() as T; } public static NetworkBehaviour.NetworkBehaviourSyncVar ReadNetworkBehaviourSyncVar(this NetworkReader reader) { uint netId = reader.ReadUInt(); byte componentIndex = default; // if netId is not 0, then index is also sent to read before returning if (netId != 0) { componentIndex = reader.ReadByte(); } return new NetworkBehaviour.NetworkBehaviourSyncVar(netId, componentIndex); } public static List ReadList(this NetworkReader reader) { int length = reader.ReadInt(); if (length < 0) return null; List result = new List(length); for (int i = 0; i < length; i++) { result.Add(reader.Read()); } return result; } public static T[] ReadArray(this NetworkReader reader) { int length = reader.ReadInt(); // we write -1 for null if (length < 0) return null; // todo throw an exception for other negative values (we never write them, likely to be attacker) // this assumes that a reader for T reads at least 1 bytes // we can't know the exact size of T because it could have a user created reader // NOTE: don't add to length as it could overflow if value is int.max if (length > reader.Length - reader.Position) { throw new EndOfStreamException($"Received array that is too large: {length}"); } T[] result = new T[length]; for (int i = 0; i < length; i++) { result[i] = reader.Read(); } return result; } public static Uri ReadUri(this NetworkReader reader) { string uriString = reader.ReadString(); return (string.IsNullOrEmpty(uriString) ? null : new Uri(uriString)); } } }