fix: Chinese encoding error with gb2312.

LLama.Examples/Assets/chat-with-kunkun-chinese.txt

@@ -0,0 +1,8 @@
+ָ�������һ������û��ĶԻ��������������һ���ڸ����涼ӵ�зḻ�������������dz����ڻش��û�������Ͱ����û���
+
+������������
+��������ã���ʲô���ܰ��������
+�Ñ����й����׶����������У�
+�������й����׶��DZ����С�
+�Ñ�����������˭��
+������

LLama.Examples/Examples/ChatChineseGB2312.cs

@@ -0,0 +1,69 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using LLama.Common;
+
+namespace LLama.Examples.Examples
+{
+    public class ChatChineseGB2312
+    {
+        private static string ConvertFromEncodingToAnother(string input, Encoding original, Encoding target)
+        {
+            byte[] bytes = original.GetBytes(input);
+            var convertedBytes = Encoding.Convert(original, target, bytes);
+            return target.GetString(convertedBytes);
+        }
+
+        public static async Task Run()
+        {
+            Encoding.RegisterProvider(CodePagesEncodingProvider.Instance); // Register gb2312 encoding
+            Console.Write("Please input your model path: ");
+            var modelPath = Console.ReadLine();
+            var prompt = File.ReadAllText("Assets/chat-with-kunkun-chinese.txt", encoding: Encoding.GetEncoding("gb2312")).Trim();
+            prompt = ConvertFromEncodingToAnother(prompt, Encoding.GetEncoding("gb2312"), Encoding.UTF8);
+
+            var parameters = new ModelParams(modelPath)
+            {
+                ContextSize = 1024,
+                Seed = 1337,
+                GpuLayerCount = 20,
+                Encoding = Encoding.UTF8
+            };
+            using var model = LLamaWeights.LoadFromFile(parameters);
+            using var context = model.CreateContext(parameters);
+            var executor = new InteractiveExecutor(context);
+
+            var session = new ChatSession(executor).WithHistoryTransform(new LLamaTransforms.DefaultHistoryTransform("用户"));
+
+            Console.ForegroundColor = ConsoleColor.Yellow;
+            Console.WriteLine("This example shows how to use Chinese with gb2312 encoding, which is common in windows. It's recommended" +
+                " to use https://huggingface.co/hfl/chinese-alpaca-2-7b-gguf/blob/main/ggml-model-q5_0.gguf, which has been verified by LLamaSharp developers.");
+            Console.ForegroundColor = ConsoleColor.White;
+
+            // show the prompt
+            Console.Write(prompt);
+            while (true)
+            {
+                await foreach (var text in session.ChatAsync(prompt, new InferenceParams()
+                {
+                    Temperature = 0.3f,
+                    TopK = 5,
+                    TopP = 0.85f,
+                    AntiPrompts = new List<string> { "用户：" },
+                    MaxTokens = 2048,
+                    RepeatPenalty = 1.05f
+                }))
+                {
+                    //Console.Write(text);
+                    Console.Write(ConvertFromEncodingToAnother(text, Encoding.UTF8, Encoding.GetEncoding("gb2312")));
+                }
+
+                Console.ForegroundColor = ConsoleColor.Green;
+                prompt = Console.ReadLine();
+                Console.ForegroundColor = ConsoleColor.White;
+            }
+        }
+    }
+}

LLama.Examples/Examples/Runner.cs

@@ -23,6 +23,7 @@ public class Runner
         { "Coding Assistant.", CodingAssistant.Run },
         { "Batch Decoding.", BatchedDecoding.Run },
         { "SK Kernel Memory.", KernelMemory.Run },
+        { "Chinese gb2312 chat", ChatChineseGB2312.Run }, 
         { "Exit", async () => Environment.Exit(0) }
     };
 

LLama.Examples/LLama.Examples.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <Import Project="..\LLama\LLamaSharp.Runtime.targets" />
   <PropertyGroup>
     <OutputType>Exe</OutputType>
@@ -68,6 +68,9 @@
     <None Update="Assets\sample-SK-Readme.pdf">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
+    <None Update="Assets\chat-with-kunkun-chinese.txt">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
   </ItemGroup>
 
 </Project>

LLama/Native/NativeApi.cs

@@ -9,6 +9,17 @@ namespace LLama.Native
 {
     using llama_token = Int32;
 
+    public enum LLamaTokenType
+    {
+        LLAMA_TOKEN_TYPE_UNDEFINED = 0,
+        LLAMA_TOKEN_TYPE_NORMAL = 1,
+        LLAMA_TOKEN_TYPE_UNKNOWN = 2,
+        LLAMA_TOKEN_TYPE_CONTROL = 3,
+        LLAMA_TOKEN_TYPE_USER_DEFINED = 4,
+        LLAMA_TOKEN_TYPE_UNUSED = 5,
+        LLAMA_TOKEN_TYPE_BYTE = 6,
+    }
+
     /// <summary>
     /// Callback from llama.cpp with log messages
     /// </summary>
@@ -243,6 +254,9 @@ public static int llama_tokenize(SafeLLamaContextHandle ctx, string text, Encodi
             }
         }
 
+        [DllImport(libraryName, CallingConvention = CallingConvention.Cdecl)]
+        public static extern LLamaTokenType llama_token_get_type(SafeLlamaModelHandle model, llama_token token);
+
         /// <summary>
         /// Get the size of the context window for the model for this context
         /// </summary>