Add native Fletcher-16.

Aaru6.Checksums/FletcherContext.cs

@@ -32,7 +32,9 @@
 
 // Disabled because the speed is abnormally slow
 
+using System;
 using System.IO;
+using System.Runtime.InteropServices;
 using System.Text;
 using Aaru.CommonTypes.Interfaces;
 using Aaru.Helpers;
@@ -315,20 +317,29 @@ namespace Aaru6.Checksums
     {
         const byte FLETCHER_MODULE = 0xFF;
         const byte NMAX            = 22;
+
+        readonly IntPtr _nativeContext;
         byte            _sum1, _sum2;
+        readonly bool   _useNative;
 
         /// <summary>Initializes the Fletcher-16 sums</summary>
         public Fletcher16Context()
         {
             _sum1 = 0xFF;
             _sum2 = 0xFF;
+
+            if(!Native.IsSupported)
+                return;
+
+            _nativeContext = fletcher16_init();
+            _useNative     = _nativeContext != IntPtr.Zero;
         }
 
         /// <inheritdoc />
         /// <summary>Updates the hash with data.</summary>
         /// <param name="data">Data buffer.</param>
         /// <param name="len">Length of buffer to hash.</param>
-        public void Update(byte[] data, uint len) => Step(ref _sum1, ref _sum2, data, len);
+        public void Update(byte[] data, uint len) => Step(ref _sum1, ref _sum2, data, len, _useNative, _nativeContext);
 
         /// <inheritdoc />
         /// <summary>Updates the hash with data.</summary>
@@ -341,6 +352,12 @@ namespace Aaru6.Checksums
         {
             ushort finalSum = (ushort)((_sum2 << 8) | _sum1);
 
+            if(!_useNative)
+                return BigEndianBitConverter.GetBytes(finalSum);
+
+            fletcher16_final(_nativeContext, ref finalSum);
+            fletcher16_free(_nativeContext);
+
             return BigEndianBitConverter.GetBytes(finalSum);
         }
 
@@ -349,6 +366,13 @@ namespace Aaru6.Checksums
         public string End()
         {
             ushort finalSum = (ushort)((_sum2 << 8) | _sum1);
+
+            if(_useNative)
+            {
+                fletcher16_final(_nativeContext, ref finalSum);
+                fletcher16_free(_nativeContext);
+            }
+
             var fletcherOutput = new StringBuilder();
 
             for(int i = 0; i < BigEndianBitConverter.GetBytes(finalSum).Length; i++)
@@ -357,8 +381,28 @@ namespace Aaru6.Checksums
             return fletcherOutput.ToString();
         }
 
-        static void Step(ref byte previousSum1, ref byte previousSum2, byte[] data, uint len)
+        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
+        static extern IntPtr fletcher16_init();
+
+        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
+        static extern int fletcher16_update(IntPtr ctx, byte[] data, uint len);
+
+        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
+        static extern int fletcher16_final(IntPtr ctx, ref ushort checksum);
+
+        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
+        static extern void fletcher16_free(IntPtr ctx);
+
+        static void Step(ref byte previousSum1, ref byte previousSum2, byte[] data, uint len, bool useNative,
+                         IntPtr nativeContext)
         {
+            if(useNative)
+            {
+                fletcher16_update(nativeContext, data, len);
+
+                return;
+            }
+
             uint sum1 = previousSum1;
             uint sum2 = previousSum2;
             uint n;
@@ -502,6 +546,17 @@ namespace Aaru6.Checksums
         /// <param name="hash">Byte array of the hash value.</param>
         public static string File(string filename, out byte[] hash)
         {
+            bool   useNative     = Native.IsSupported;
+            IntPtr nativeContext = IntPtr.Zero;
+
+            if(useNative)
+            {
+                nativeContext = fletcher16_init();
+
+                if(nativeContext == IntPtr.Zero)
+                    useNative = false;
+            }
+
             var fileStream = new FileStream(filename, FileMode.Open);
 
             byte localSum1 = 0xFF;
@@ -512,13 +567,19 @@ namespace Aaru6.Checksums
 
             while(read > 0)
             {
-                Step(ref localSum1, ref localSum2, buffer, (uint)read);
+                Step(ref localSum1, ref localSum2, buffer, (uint)read, useNative, nativeContext);
 
                 read = fileStream.Read(buffer, 0, 65536);
             }
 
             ushort finalSum = (ushort)((localSum2 << 8) | localSum1);
 
+            if(useNative)
+            {
+                fletcher16_final(nativeContext, ref finalSum);
+                fletcher16_free(nativeContext);
+            }
+
             hash = BigEndianBitConverter.GetBytes(finalSum);
 
             var fletcherOutput = new StringBuilder();
@@ -537,13 +598,30 @@ namespace Aaru6.Checksums
         /// <param name="hash">Byte array of the hash value.</param>
         public static string Data(byte[] data, uint len, out byte[] hash)
         {
+            bool   useNative     = Native.IsSupported;
+            IntPtr nativeContext = IntPtr.Zero;
+
+            if(useNative)
+            {
+                nativeContext = fletcher16_init();
+
+                if(nativeContext == IntPtr.Zero)
+                    useNative = false;
+            }
+
             byte localSum1 = 0xFF;
             byte localSum2 = 0xFF;
 
-            Step(ref localSum1, ref localSum2, data, len);
+            Step(ref localSum1, ref localSum2, data, len, useNative, nativeContext);
 
             ushort finalSum = (ushort)((localSum2 << 8) | localSum1);
 
+            if(useNative)
+            {
+                fletcher16_final(nativeContext, ref finalSum);
+                fletcher16_free(nativeContext);
+            }
+
             hash = BigEndianBitConverter.GetBytes(finalSum);
 
             var adlerOutput = new StringBuilder();

AaruBenchmark/Checksums/Aaru.cs

@@ -148,12 +148,12 @@ namespace AaruBenchmark.Checksums
             IChecksum ctx = new CRC16CCITTContext();
             ctx.Update(data);
             byte[] result = ctx.Final();
-            /*
+
             if(result?.Length != _expectedRandomCrc16Ccitt.Length)
                 throw new Exception("Invalid hash length");
 
             if(result.Where((t, i) => t != _expectedRandomCrc16Ccitt[i]).Any())
-                            throw new Exception("Invalid hash value");*/
+                throw new Exception("Invalid hash value");
         }
 
         public static void Crc16()

AaruBenchmark/Checksums/Aaru6.cs

@@ -77,6 +77,8 @@ namespace AaruBenchmark.Checksums
 
         public static void Fletcher16()
         {
+            Native.ForceManaged = true;
+
             byte[] data = new byte[1048576];
 
             var fs = new FileStream(Path.Combine(Program.Folder, "random"), FileMode.Open, FileAccess.Read);

AaruBenchmark/Checksums/AaruNative.cs

@@ -76,18 +76,6 @@ namespace AaruBenchmark.Checksums
             0xb5, 0xf2, 0x8c, 0xbb, 0x4a, 0xa5, 0x1b, 0x40, 0x7c, 0xb6
         };
 
-        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
-        static extern IntPtr fletcher16_init();
-
-        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
-        static extern int fletcher16_update(IntPtr ctx, byte[] data, uint len);
-
-        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
-        static extern int fletcher16_final(IntPtr ctx, ref ushort crc);
-
-        [DllImport("libAaru.Checksums.Native", SetLastError = true)]
-        static extern void fletcher16_free(IntPtr ctx);
-
         [DllImport("libAaru.Checksums.Native", SetLastError = true)]
         static extern IntPtr fletcher32_init();
 
@@ -114,38 +102,23 @@ namespace AaruBenchmark.Checksums
 
         public static void Fletcher16()
         {
+            Native.ForceManaged = false;
+
             byte[] data = new byte[1048576];
-            ushort fletcher16 = 0;
-            byte[] hash;
 
             var fs = new FileStream(Path.Combine(Program.Folder, "random"), FileMode.Open, FileAccess.Read);
 
             fs.Read(data, 0, 1048576);
             fs.Close();
             fs.Dispose();
+            IChecksum ctx = new Fletcher16Context();
+            ctx.Update(data);
+            byte[] result = ctx.Final();
 
-            IntPtr ctx = fletcher16_init();
+            if(result?.Length != _expectedRandomFletcher16.Length)
+                throw new Exception("Invalid hash length");
 
-            if(ctx == IntPtr.Zero)
+            if(result.Where((t, i) => t != _expectedRandomFletcher16[i]).Any())
-                throw new Exception("Could not initialize digest");
-
-            int ret = fletcher16_update(ctx, data, (uint)data.Length);
-
-            if(ret != 0)
-                throw new Exception("Could not digest block");
-
-            ret = fletcher16_final(ctx, ref fletcher16);
-
-            if(ret != 0)
-                throw new Exception("Could not finalize hash");
-
-            fletcher16_free(ctx);
-
-            fletcher16 = (ushort)((fletcher16 << 8) | (fletcher16 >> 8));
-
-            hash = BitConverter.GetBytes(fletcher16);
-
-            if(hash.Where((t, i) => t != _expectedRandomFletcher16[i]).Any())
                 throw new Exception("Invalid hash value");
         }