Removing unsafe code for netcoreapp targets.

Author: Stefán J. Sigurðarson

projects/RabbitMQ.Client/client/impl/WireFormatting.cs

@@ -168,6 +168,10 @@ public static int ReadShortstr(ReadOnlySpan<byte> span, out string value)
             // equals span.Length >= byteCount + 1
             if (span.Length > byteCount)
             {
+#if NETCOREAPP
+                value = Encoding.UTF8.GetString(span.Slice(1, byteCount));
+                return 1 + byteCount;
+#else
                 unsafe
                 {
                     fixed (byte* bytes = &MemoryMarshal.GetReference(span.Slice(1)))
@@ -176,6 +180,7 @@ public static int ReadShortstr(ReadOnlySpan<byte> span, out string value)
                         return 1 + byteCount;
                     }
                 }
+#endif
             }
 
             throw new ArgumentOutOfRangeException("span", $"Span has not enough space ({span.Length} instead of {byteCount + 1})");
@@ -725,6 +730,18 @@ public static int WriteShortstr(Span<byte> span, string val)
                 maxLength = byte.MaxValue;
             }
 
+#if NETCOREAPP
+            try
+            {
+                int bytesWritten = Encoding.UTF8.GetBytes(val, span.Slice(1));
+                span[0] = (byte)bytesWritten;
+                return bytesWritten + 1;
+            }
+            catch (ArgumentException e)
+            {
+                throw new ArgumentOutOfRangeException($"Value exceeds the maximum allowed length of {maxLength} bytes.", e);
+            }
+#else
             unsafe
             {
                 fixed (char* chars = val)
@@ -742,6 +759,7 @@ public static int WriteShortstr(Span<byte> span, string val)
                     }
                 }
             }
+#endif
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -753,6 +771,11 @@ public static int WriteLongstr(Span<byte> span, string val)
                 return 4;
             }
 
+#if NETCOREAPP
+            int bytesWritten = Encoding.UTF8.GetBytes(val, span.Slice(4));
+            NetworkOrderSerializer.WriteUInt32(span, (uint)bytesWritten);
+            return bytesWritten + 4;
+#else
             unsafe
             {
                 fixed (char* chars = val)
@@ -763,6 +786,7 @@ public static int WriteLongstr(Span<byte> span, string val)
                     return bytesWritten + 4;
                 }
             }
+#endif
         }
 
         public static int WriteTable(Span<byte> span, IDictionary val)