Add read methods to buffer classes

robotdotnet · Jan 16, 2024 · 8d615e3 · 8d615e3
1 parent bc30e17
commit 8d615e3
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Showing 4 changed files with 80 additions and 22 deletions.
diff --git a/src/wpiutil/Serialization/Protobuf/IProtobuf.cs b/src/wpiutil/Serialization/Protobuf/IProtobuf.cs
@@ -1,4 +1,5 @@
-using Google.Protobuf;
+using System;
+using Google.Protobuf;
 using Google.Protobuf.Reflection;
 
 namespace WPIUtil.Serialization.Protobuf;
@@ -17,4 +18,28 @@ public interface IProtobuf<T, MessageType> : IProtobufBase where MessageType : I
     T Unpack(MessageType msg);
 
     void Pack(MessageType msg, T value);
+
+    void UnpackInto(ref T value, MessageType msg)
+    {
+        throw new NotSupportedException("Object does not support UnpackInto");
+    }
+
+    void ForEachDescriptor(Func<string, bool> exists, Action<string, byte[]> fn)
+    {
+        ForEachDescriptorImpl(Descriptor.File, exists, fn);
+    }
+
+    private static void ForEachDescriptorImpl(FileDescriptor desc, Func<string, bool> exists, Action<string, byte[]> fn)
+    {
+        string name = $"proto:{desc.Name}";
+        if (exists(name))
+        {
+            return;
+        }
+        foreach (var d in desc.Dependencies)
+        {
+            ForEachDescriptorImpl(d, exists, fn);
+        }
+        fn(name, desc.ToProto().ToByteArray());
+    }
 }
diff --git a/src/wpiutil/Serialization/Protobuf/ProtobufBuffer.cs b/src/wpiutil/Serialization/Protobuf/ProtobufBuffer.cs
@@ -3,23 +3,18 @@
 
 namespace WPIUtil.Serialization.Protobuf;
 
-public sealed class ProtobufBuffer<T, MessageType> where MessageType : IMessage
+public struct ProtobufBuffer<T, MessageType> where MessageType : IMessage
                                                    where T : IProtobufSerializable<T, MessageType>
 {
-    private ProtobufBuffer()
+    public ProtobufBuffer()
     {
         Proto = T.Proto;
         m_msg = Proto.CreateMessage();
     }
 
-    public static ProtobufBuffer<T, MessageType> Create()
-    {
-        return new ProtobufBuffer<T, MessageType>();
-    }
-
     public IProtobuf<T, MessageType> Proto { get; }
 
-    public string TypeString => Proto.TypeString;
+    public readonly string TypeString => Proto.TypeString;
 
     public ReadOnlySpan<byte> Write(T value)
     {
@@ -33,12 +28,18 @@ public ReadOnlySpan<byte> Write(T value)
         return m_buf.AsSpan()[..size];
     }
 
-    public T Read(ReadOnlySpan<byte> buffer)
+    public readonly T Read(ReadOnlySpan<byte> buffer)
     {
         m_msg.MergeFrom(buffer);
         return Proto.Unpack(m_msg);
     }
 
+    public readonly void ReadInto(ref T output, ReadOnlySpan<byte> buffer)
+    {
+        m_msg.MergeFrom(buffer);
+        Proto.UnpackInto(ref output, m_msg);
+    }
+
     private readonly MessageType m_msg;
     private byte[] m_buf = new byte[1024];
 }
diff --git a/src/wpiutil/Serialization/Struct/Struct.cs b/src/wpiutil/Serialization/Struct/Struct.cs
@@ -1,4 +1,6 @@
-namespace WPIUtil.Serialization.Struct;
+using System;
+
+namespace WPIUtil.Serialization.Struct;
 
 public interface IStructBase
 {
@@ -17,4 +19,9 @@ public interface IStruct<T> : IStructBase
     T Unpack(ref StructUnpacker buffer);
 
     void Pack(ref StructPacker buffer, T value);
+
+    void UnpackInto(ref T value, ref StructUnpacker buffer)
+    {
+        throw new NotSupportedException("Object does not support UnpackInto");
+    }
 }
diff --git a/src/wpiutil/Serialization/Struct/StructBuffer.cs b/src/wpiutil/Serialization/Struct/StructBuffer.cs
@@ -2,24 +2,21 @@
 
 namespace WPIUtil.Serialization.Struct;
 
-public sealed class StructBuffer<T>
+public struct StructBuffer<T> where T : IStructSerializable<T>
 {
     private readonly int m_structSize;
     private byte[] m_buf;
+    public IStruct<T> Struct { get; }
+
+    public readonly string TypeString => Struct.TypeString;
 
-    private StructBuffer(IStruct<T> value)
+    public StructBuffer()
     {
-        m_structSize = value.Size;
+        Struct = T.Struct;
+        m_structSize = Struct.Size;
         m_buf = new byte[m_structSize];
-        Struct = value;
     }
 
-    public static StructBuffer<T> Create(IStruct<T> value) => new(value);
-
-    public IStruct<T> Struct { get; }
-
-    public string TypeString => Struct.TypeString;
-
     public void Reserve(int nelem)
     {
         if ((nelem * m_structSize) > m_buf.Length)
@@ -28,13 +25,25 @@ public void Reserve(int nelem)
         }
     }
 
-    public ReadOnlySpan<byte> Write(T value)
+    public readonly ReadOnlySpan<byte> Write(T value)
     {
         StructPacker packer = new(m_buf);
         Struct.Pack(ref packer, value);
         return packer.Filled;
     }
 
+    public readonly T Read(ReadOnlySpan<byte> buffer)
+    {
+        StructUnpacker unpacker = new(buffer);
+        return Struct.Unpack(ref unpacker);
+    }
+
+    public readonly void ReadInto(ref T output, ReadOnlySpan<byte> buffer)
+    {
+        StructUnpacker unpacker = new(buffer);
+        Struct.UnpackInto(ref output, ref unpacker);
+    }
+
     public ReadOnlySpan<byte> WriteArray(ReadOnlySpan<T> values)
     {
         if ((values.Length * m_structSize) > m_buf.Length)
@@ -48,4 +57,20 @@ public ReadOnlySpan<byte> WriteArray(ReadOnlySpan<T> values)
         }
         return packer.Filled;
     }
+
+    public readonly T[] ReadArray(ReadOnlySpan<byte> buffer)
+    {
+        if ((buffer.Length % m_structSize) != 0)
+        {
+            throw new Exception("Buffer size not a multiple of struct size");
+        }
+        int nelem = buffer.Length / m_structSize;
+        T[] arr = new T[nelem];
+        StructUnpacker unpacker = new(buffer);
+        for (int i = 0; i < nelem; i++)
+        {
+            arr[i] = Struct.Unpack(ref unpacker);
+        }
+        return arr;
+    }
 }