In/outgoing Span<byte> support, linux net45 build

- Closes #587
- Add netfx.props and tweak sbxee-dll csproj to allow building sbe.dll
  for net45 on Linux using dotnet sdk following:
  https://andrewlock.net/building-net-framework-asp-net-core-apps-on-linux-using-mono-and-the-net-cli/
- Remove packages.config files from projects already converted to SDK style project since
  those files serve no purpose other than confusing potential contributors...
- Intoroduce minimal Span<byte> GetBytes/SetBytes implementation for copying
  to/from Span<byte> to sbe.dll itself.
- Change code generation for array types to use Span<byte> internally keeping the
  original functionality intact with no (hopefully!) visible user facing changes except
  for the addtitional Get/Set methods accepting Span<byte> being added to the mix.

Author: Dan Shechter

csharp/netfx.props

@@ -0,0 +1,26 @@
+<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">  
+  <PropertyGroup>
+    <!-- When compiling .NET SDK 2.0 projects targeting .NET 4.x on Mono using 'dotnet build' you -->
+    <!-- have to teach MSBuild where the Mono copy of the reference asssemblies is -->
+    <TargetIsMono Condition="$(TargetFramework.StartsWith('net4')) and '$(OS)' == 'Unix'">true</TargetIsMono>
+
+    <!-- Look in the standard install locations -->
+    <MonoBasePath Condition="'$(MonoBasePath)' == '' AND '$(TargetIsMono)' == 'true' AND EXISTS('/Library/Frameworks/Mono.framework/Versions/Current/lib/mono')">/Library/Frameworks/Mono.framework/Versions/Current/lib/mono</MonoBasePath>
+    <MonoBasePath Condition="'$(MonoBasePath)' == '' AND '$(TargetIsMono)' == 'true' AND EXISTS('/usr/lib/mono')">/usr/lib/mono</MonoBasePath>
+    <MonoBasePath Condition="'$(MonoBasePath)' == '' AND '$(TargetIsMono)' == 'true' AND EXISTS('/usr/local/lib/mono')">/usr/local/lib/mono</MonoBasePath>
+
+    <!-- If we found Mono reference assemblies, then use them -->
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net45'">$(MonoBasePath)/4.5-api</FrameworkPathOverride>
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net451'">$(MonoBasePath)/4.5.1-api</FrameworkPathOverride>
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net452'">$(MonoBasePath)/4.5.2-api</FrameworkPathOverride>
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net46'">$(MonoBasePath)/4.6-api</FrameworkPathOverride>
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net461'">$(MonoBasePath)/4.6.1-api</FrameworkPathOverride>
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net462'">$(MonoBasePath)/4.6.2-api</FrameworkPathOverride>
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net47'">$(MonoBasePath)/4.7-api</FrameworkPathOverride>
+    <FrameworkPathOverride Condition="'$(MonoBasePath)' != '' AND '$(TargetFramework)' == 'net471'">$(MonoBasePath)/4.7.1-api</FrameworkPathOverride>
+    <EnableFrameworkPathOverride Condition="'$(MonoBasePath)' != ''">true</EnableFrameworkPathOverride>
+
+    <!-- Add the Facades directory.  Not sure how else to do this. Necessary at least for .NET 4.5 -->
+    <AssemblySearchPaths Condition="'$(MonoBasePath)' != ''">$(FrameworkPathOverride)/Facades;$(AssemblySearchPaths)</AssemblySearchPaths>
+  </PropertyGroup>
+</Project> 

csharp/sbe-dll/DirectBuffer.cs

@@ -9,7 +9,7 @@ namespace Org.SbeTool.Sbe.Dll
     public sealed unsafe class DirectBuffer : IDisposable
     {
         /// <summary>
-        /// Delegate invoked if buffer size is too small. 
+        /// Delegate invoked if buffer size is too small.
         /// </summary>
         /// <param name="existingBufferSize"></param>
         /// <param name="requestedBufferSize"></param>
@@ -66,7 +66,7 @@ public DirectBuffer(byte* pBuffer, int bufferLength, BufferOverflowDelegate buff
         /// <summary>
         /// Creates a DirectBuffer that can later be wrapped
         /// </summary>
-        public DirectBuffer() 
+        public DirectBuffer()
         {
         }
 
@@ -569,6 +569,22 @@ public void DoublePutLittleEndian(int index, double value)
 
         #endregion
 
+        /// <summary>
+        /// Creates a <see cref="Span{T}" /> on top of the underlying buffer
+        /// </summary>
+        /// <param name="index">index  in the underlying buffer to start from.</param>
+        /// <param name="length">length of the supplied buffer to use.</param>
+        /// <returns>The new <see cref="Span{T}" /> wrapping the requested memory</returns>
+        public Span<T> AsSpan<T>(int index, int length) => new Span<T>(_pBuffer + index, length);
+
+        /// <summary>
+        /// Creates a <see cref="ReadOnlySpan{T}" /> on top of the underlying buffer
+        /// </summary>
+        /// <param name="index">index  in the underlying buffer to start from.</param>
+        /// <param name="length">length of the supplied buffer to use.</param>
+        /// <returns>The new <see cref="ReadOnlySpan{T}" /> wrapping the requested memory</returns>
+        public ReadOnlySpan<T> AsReadOnlySpan<T>(int index, int length) => new ReadOnlySpan<T>(_pBuffer + index, length);
+
         /// <summary>
         /// Copies a range of bytes from the underlying into a supplied byte array.
         /// </summary>
@@ -585,6 +601,20 @@ public int GetBytes(int index, byte[] destination, int offsetDestination, int le
             return count;
         }
 
+        /// <summary>
+        /// Copies a range of bytes from the underlying into a supplied <see cref="Span{T}" />.
+        /// </summary>
+        /// <param name="index">index  in the underlying buffer to start from.</param>
+        /// <param name="destination"><see cref="Span{T}" /> into which the bytes will be copied.</param>
+        /// <returns>count of bytes copied.</returns>
+        public int GetBytes(int index, Span<byte> destination)
+        {
+            int count = Math.Min(destination.Length, _capacity - index);
+            AsReadOnlySpan<byte>(index, count).CopyTo(destination);
+
+            return count;
+        }
+
         /// <summary>
         /// Writes a byte array into the underlying buffer.
         /// </summary>
@@ -601,6 +631,20 @@ public int SetBytes(int index, byte[] src, int offset, int length)
             return count;
         }
 
+        /// <summary>
+        /// Writes a <see cref="Span{T}" /> into the underlying buffer.
+        /// </summary>
+        /// <param name="index">index  in the underlying buffer to start from.</param>
+        /// <param name="src">source <see cref="Span{T}" /> to be copied to the underlying buffer.</param>
+        /// <returns>count of bytes copied.</returns>
+        public int SetBytes(int index, ReadOnlySpan<byte> src)
+        {
+            int count = Math.Min(src.Length, _capacity - index);
+            src.CopyTo(AsSpan<byte>(index, count));
+
+            return count;
+        }
+
         /// <summary>
         /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
         /// </summary>
@@ -638,4 +682,4 @@ private void FreeGCHandle()
             }
         }
     }
-}
+}

csharp/sbe-dll/packages.config

@@ -1,4 +1,5 @@
 <Project Sdk="Microsoft.NET.Sdk">
+  <Import Project="..\netfx.props" />
 
   <PropertyGroup>
     <TargetFrameworks>net45;netstandard2.0</TargetFrameworks>
@@ -10,11 +11,19 @@
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|net45|AnyCPU'">
-    <DocumentationFile>bin\Release\net45\SBE.xml</DocumentationFile>
+    <DocumentationFile>bin\release\net45\SBE.xml</DocumentationFile>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(TargetFramework)|$(Platform)'=='Release|netstandard2.0|AnyCPU'">
-    <DocumentationFile>bin\Release\netstandard2.0\SBE.xml</DocumentationFile>
+    <DocumentationFile>bin\release\netstandard2.0\SBE.xml</DocumentationFile>
   </PropertyGroup>
+ 
+  <ItemGroup Condition=" '$(TargetFramework)' == 'net45' ">
+    <Reference Include="System.Runtime" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="System.Memory" Version="4.5.1" />
+  </ItemGroup>
 
 </Project>

csharp/sbe-dll/sbe-dll.csproj

@@ -358,16 +358,21 @@ private CharSequence generateVarData(final List<Token> tokens, final String inde
                     sizeOfLengthField));
 
                 sb.append(String.format("\n" +
-                    indent + "public int Get%1$s(byte[] dst, int dstOffset, int length)\n" +
+                    indent + "public int Get%1$s(byte[] dst, int dstOffset, int length) =>\n" +
+                    indent + INDENT + "Get%1$s(new Span<byte>(dst, dstOffset, length));\n",
+                    propertyName));
+
+                sb.append(String.format("\n" +
+                    indent + "public int Get%1$s(Span<byte> dst)\n" +
                     indent + "{\n" +
                     "%2$s" +
                     indent + INDENT + "const int sizeOfLengthField = %3$d;\n" +
                     indent + INDENT + "int limit = _parentMessage.Limit;\n" +
                     indent + INDENT + "_buffer.CheckLimit(limit + sizeOfLengthField);\n" +
                     indent + INDENT + "int dataLength = (int)_buffer.%4$sGet%5$s(limit);\n" +
-                    indent + INDENT + "int bytesCopied = Math.Min(length, dataLength);\n" +
+                    indent + INDENT + "int bytesCopied = Math.Min(dst.Length, dataLength);\n" +
                     indent + INDENT + "_parentMessage.Limit = limit + sizeOfLengthField + dataLength;\n" +
-                    indent + INDENT + "_buffer.GetBytes(limit + sizeOfLengthField, dst, dstOffset, bytesCopied);\n\n" +
+                    indent + INDENT + "_buffer.GetBytes(limit + sizeOfLengthField, dst.Slice(0, bytesCopied));\n\n" +
                     indent + INDENT + "return bytesCopied;\n" +
                     indent + "}\n",
                     propertyName,
@@ -377,14 +382,19 @@ private CharSequence generateVarData(final List<Token> tokens, final String inde
                     byteOrderStr));
 
                 sb.append(String.format("\n" +
-                    indent + "public int Set%1$s(byte[] src, int srcOffset, int length)\n" +
+                    indent + "public int Set%1$s(byte[] src, int srcOffset, int length) =>\n" +
+                    indent + INDENT + "Set%1$s(new ReadOnlySpan<byte>(src, srcOffset, length));\n",
+                    propertyName));
+
+                sb.append(String.format("\n" +
+                    indent + "public int Set%1$s(ReadOnlySpan<byte> src)\n" +
                     indent + "{\n" +
                     indent + INDENT + "const int sizeOfLengthField = %2$d;\n" +
                     indent + INDENT + "int limit = _parentMessage.Limit;\n" +
-                    indent + INDENT + "_parentMessage.Limit = limit + sizeOfLengthField + length;\n" +
-                    indent + INDENT + "_buffer.%3$sPut%5$s(limit, (%4$s)length);\n" +
-                    indent + INDENT + "_buffer.SetBytes(limit + sizeOfLengthField, src, srcOffset, length);\n\n" +
-                    indent + INDENT + "return length;\n" +
+                    indent + INDENT + "_parentMessage.Limit = limit + sizeOfLengthField + src.Length;\n" +
+                    indent + INDENT + "_buffer.%3$sPut%5$s(limit, (%4$s)src.Length);\n" +
+                    indent + INDENT + "_buffer.SetBytes(limit + sizeOfLengthField, src);\n\n" +
+                    indent + INDENT + "return src.Length;\n" +
                     indent + "}\n",
                     propertyName,
                     sizeOfLengthField,
@@ -756,44 +766,30 @@ private CharSequence generateArrayProperty(
 
         sb.append(String.format("\n" +
             indent + "public const int %sLength = %d;\n",
-            propName,
-            fieldLength));
+            propName, fieldLength));
 
         sb.append(String.format("\n" +
             indent + "public %1$s Get%2$s(int index)\n" +
             indent + "{\n" +
-            indent + INDENT + "if (index < 0 || index >= %3$d)\n" +
-            indent + INDENT + "{\n" +
+            indent + INDENT + "if (index < 0 || index >= %3$d) {\n" +
             indent + INDENT + INDENT + "throw new IndexOutOfRangeException(\"index out of range: index=\" + index);\n" +
             indent + INDENT + "}\n\n" +
             "%4$s" +
             indent + INDENT + "return _buffer.%5$sGet%8$s(_offset + %6$d + (index * %7$d));\n" +
             indent + "}\n",
-            typeName,
-            propName,
-            fieldLength,
+            typeName, propName, fieldLength,
             generateFieldNotPresentCondition(token.version(), token.encoding(), indent),
-            typePrefix,
-            offset,
-            typeSize,
-            byteOrderStr));
+            typePrefix, offset, typeSize, byteOrderStr));
 
         sb.append(String.format("\n" +
             indent + "public void Set%1$s(int index, %2$s value)\n" +
             indent + "{\n" +
-            indent + INDENT + "if (index < 0 || index >= %3$d)\n" +
-            indent + INDENT + "{\n" +
+            indent + INDENT + "if (index < 0 || index >= %3$d) {\n" +
             indent + INDENT + INDENT + "throw new IndexOutOfRangeException(\"index out of range: index=\" + index);\n" +
             indent + INDENT + "}\n\n" +
             indent + INDENT + "_buffer.%4$sPut%7$s(_offset + %5$d + (index * %6$d), value);\n" +
             indent + "}\n",
-            propName,
-            typeName,
-            fieldLength,
-            typePrefix,
-            offset,
-            typeSize,
-            byteOrderStr));
+            propName, typeName, fieldLength, typePrefix, offset, typeSize, byteOrderStr));
 
         if (token.encoding().primitiveType() == PrimitiveType.CHAR)
         {
@@ -803,39 +799,43 @@ private CharSequence generateArrayProperty(
                 indent + "public int Get%1$s(byte[] dst, int dstOffset)\n" +
                 indent + "{\n" +
                 indent + INDENT + "const int length = %2$d;\n" +
-                indent + INDENT + "if (dstOffset < 0 || dstOffset > (dst.Length - length))\n" +
-                indent + INDENT + "{\n" +
-                indent + INDENT + INDENT + "throw new IndexOutOfRangeException(" +
-                "\"dstOffset out of range for copy: offset=\" + dstOffset);\n" +
+                "%3$s" +
+                indent + INDENT + "return Get%1$s(new Span<byte>(dst, dstOffset, length));\n" +
+                indent + "}\n",
+                propName, fieldLength, generateArrayFieldNotPresentCondition(token.version(), indent), offset));
+
+            sb.append(String.format("\n" +
+                indent + "public int Get%1$s(Span<byte> dst)\n" +
+                indent + "{\n" +
+                indent + INDENT + "const int length = %2$d;\n" +
+                indent + INDENT + "if (dst.Length < length) {\n" +
+                indent + INDENT + INDENT +
+                "throw new ArgumentOutOfRangeException($\"dst.Length={dst.Length} is too large.\");\n" +
                 indent + INDENT + "}\n\n" +
                 "%3$s" +
-                indent + INDENT + "_buffer.GetBytes(_offset + %4$d, dst, dstOffset, length);\n" +
+                indent + INDENT + "_buffer.GetBytes(_offset + %4$d, dst);\n" +
                 indent + INDENT + "return length;\n" +
                 indent + "}\n",
-                propName,
-                fieldLength,
-                generateArrayFieldNotPresentCondition(token.version(), indent),
-                offset));
+                propName, fieldLength, generateArrayFieldNotPresentCondition(token.version(), indent), offset));
 
             sb.append(String.format("\n" +
                 indent + "public void Set%1$s(byte[] src, int srcOffset)\n" +
                 indent + "{\n" +
+                indent + INDENT + "Set%1$s(new ReadOnlySpan<byte>(src, srcOffset, src.Length - srcOffset));\n" +
+                indent + "}\n",
+                propName, fieldLength, offset));
+
+            sb.append(String.format("\n" +
+                indent + "public void Set%1$s(ReadOnlySpan<byte> src)\n" +
+                indent + "{\n" +
                 indent + INDENT + "const int length = %2$d;\n" +
-                indent + INDENT + "if (srcOffset < 0 || srcOffset > src.Length)\n" +
-                indent + INDENT + "{\n" +
-                indent + INDENT + INDENT +
-                "throw new IndexOutOfRangeException(\"srcOffset out of range for copy: offset=\" + srcOffset);\n" +
-                indent + INDENT + "}\n\n" +
-                indent + INDENT + "if (src.Length > length)\n" +
-                indent + INDENT + "{\n" +
+                indent + INDENT + "if (src.Length > length) {\n" +
                 indent + INDENT + INDENT +
                 "throw new ArgumentOutOfRangeException($\"src.Length={src.Length} is too large.\");\n" +
                 indent + INDENT + "}\n\n" +
-                indent + INDENT + "_buffer.SetBytes(_offset + %3$d, src, srcOffset, src.Length - srcOffset);\n" +
+                indent + INDENT + "_buffer.SetBytes(_offset + %3$d, src);\n" +
                 indent + "}\n",
-                propName,
-                fieldLength,
-                offset));
+                propName, fieldLength, offset));
         }
 
         return sb;