Fix FBMMessageHeader default and session connection status

3 files changed, 20 insertions, 320 deletions

diff --git a/lib/Net.Messaging.FBM/src/Client/FBMBuffer.cs b/lib/Net.Messaging.FBM/src/Client/FBMBuffer.cs
index 95a5bb8..fac41a6 100644
--- a/lib/Net.Messaging.FBM/src/Client/FBMBuffer.cs
+++ b/lib/Net.Messaging.FBM/src/Client/FBMBuffer.cs
@@ -24,6 +24,9 @@
 
 using System;
 using System.Buffers;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+
 using VNLib.Utils.IO;
 
 namespace VNLib.Net.Messaging.FBM.Client
@@ -31,7 +34,7 @@ namespace VNLib.Net.Messaging.FBM.Client
     /// <summary>
     /// Represents a shared internal character and bianry buffer for
     /// </summary>
-    internal sealed class FBMBuffer : IDisposable
+    internal sealed class FBMBuffer : IFBMHeaderBuffer, IDisposable
     {
         private readonly IMemoryOwner<byte> Handle;
 
@@ -70,16 +73,7 @@ namespace VNLib.Net.Messaging.FBM.Client
             //Return the internal writer
             return _writer;
         }
-
-        /// <summary>
-        /// Gets the buffer manager for managing response headers
-        /// </summary>
-        /// <returns>The <see cref="FBMHeaderBuffer"/> for managing response header buffers</returns>
-        public FBMHeaderBuffer GetResponseHeaderBuffer()
-        {
-            //Get a buffer wrapper around the memory handle
-            return new FBMHeaderBuffer(Handle.Memory);
-        }
+       
 
         public void Dispose()
         {
@@ -100,6 +94,20 @@ namespace VNLib.Net.Messaging.FBM.Client
             Helpers.WriteMessageid(RequestBuffer, messageId);
         }
 
+        ///<inheritdoc/>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        Span<char> IFBMHeaderBuffer.GetSpan(int offset, int count)
+        {
+            //Get the character span
+            Span<char> span = MemoryMarshal.Cast<byte, char>(Handle.Memory.Span);
+            return span.Slice(offset, count);
+        }
+
+        ///<inheritdoc/>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        Span<char> IFBMHeaderBuffer.GetSpan() => MemoryMarshal.Cast<byte, char>(Handle.Memory.Span);
+
+
         private sealed class BinaryRequestAccumulator : IDataAccumulator<byte>
         {
             private readonly int Size;
diff --git a/lib/Net.Messaging.FBM/src/Client/FBMRequest.cs b/lib/Net.Messaging.FBM/src/Client/FBMRequest.cs
index aaf3926..01302a9 100644
--- a/lib/Net.Messaging.FBM/src/Client/FBMRequest.cs
+++ b/lib/Net.Messaging.FBM/src/Client/FBMRequest.cs
@@ -210,12 +210,9 @@ namespace VNLib.Net.Messaging.FBM.Client
                  * The headers are read into a list of key-value pairs and the stream
                  * is positioned to the start of the message body
                  */
-               
-                //Get the response header buffer for parsing
-                FBMHeaderBuffer headerBuf = Buffer.GetResponseHeaderBuffer();
 
                 //Parse message headers
-                HeaderParseError statusFlags = Helpers.ParseHeaders(Response, in headerBuf, ResponseHeaderList, HeaderEncoding);
+                HeaderParseError statusFlags = Helpers.ParseHeaders(Response, Buffer, ResponseHeaderList, HeaderEncoding);
 
                 //return response structure
                 return new(Response, statusFlags, ResponseHeaderList, OnResponseDisposed);
diff --git a/lib/Net.Messaging.FBM/src/Client/Helpers.cs b/lib/Net.Messaging.FBM/src/Client/Helpers.cs
deleted file mode 100644
index 0b9e7bd..0000000
--- a/lib/Net.Messaging.FBM/src/Client/Helpers.cs
+++ /dev/null
@@ -1,305 +0,0 @@
-/*
-* Copyright (c) 2022 Vaughn Nugent
-* 
-* Library: VNLib
-* Package: VNLib.Net.Messaging.FBM
-* File: Helpers.cs 
-*
-* Helpers.cs is part of VNLib.Net.Messaging.FBM which is part of the larger 
-* VNLib collection of libraries and utilities.
-*
-* VNLib.Net.Messaging.FBM is free software: you can redistribute it and/or modify 
-* it under the terms of the GNU Affero General Public License as 
-* published by the Free Software Foundation, either version 3 of the
-* License, or (at your option) any later version.
-*
-* VNLib.Net.Messaging.FBM is distributed in the hope that it will be useful,
-* but WITHOUT ANY WARRANTY; without even the implied warranty of
-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-* GNU Affero General Public License for more details.
-*
-* You should have received a copy of the GNU Affero General Public License
-* along with this program.  If not, see https://www.gnu.org/licenses/.
-*/
-
-using System;
-using System.IO;
-using System.Text;
-using System.Buffers.Binary;
-using System.Collections.Generic;
-using System.Security.Cryptography;
-using System.Runtime.CompilerServices;
-
-using VNLib.Utils;
-using VNLib.Utils.IO;
-using VNLib.Utils.Memory;
-using VNLib.Utils.Extensions;
-
-namespace VNLib.Net.Messaging.FBM
-{
-    /// <summary>
-    /// Contains FBM library helper methods
-    /// </summary>
-    public static class Helpers
-    {
-        /// <summary>
-        /// The message-id of a connection control frame / out of band message
-        /// </summary>
-        public const int CONTROL_FRAME_MID = -500;
-
-        /// <summary>
-        /// Gets the default header character encoding instance
-        /// </summary>
-        public static Encoding DefaultEncoding { get; } = Encoding.UTF8;
-        
-        /// <summary>
-        /// The FBM protocol header line termination symbols
-        /// </summary>
-        public static ReadOnlyMemory<byte> Termination { get; } = new byte[] { 0xFF, 0xF1 };
-
-        /// <summary>
-        /// Parses the header line for a message-id
-        /// </summary>
-        /// <param name="line">A sequence of bytes that make up a header line</param>
-        /// <returns>The message-id if parsed, -1 if message-id is not valid</returns>
-        public static int GetMessageId(ReadOnlySpan<byte> line)
-        {
-            //Make sure the message line is large enough to contain a message-id
-            if (line.Length < 1 + sizeof(int))
-            {
-                return -1;
-            }
-            
-            //The first byte should be the header id
-            HeaderCommand headerId = (HeaderCommand)line[0];
-            
-            //Make sure the headerid is set
-            if (headerId != HeaderCommand.MessageId)
-            {
-                return -2;
-            }
-            
-            //Get the messageid after the header byte
-            ReadOnlySpan<byte> messageIdSegment = line.Slice(1, sizeof(int));
-            
-            //get the messageid from the messageid segment
-            return BinaryPrimitives.ReadInt32BigEndian(messageIdSegment);
-        }
-
-        /// <summary>
-        /// Appends the message id header to the accumulator 
-        /// </summary>
-        /// <param name="accumulator">The accumulatore to write the message id to</param>
-        /// <param name="messageid">The message id to write to the accumulator</param>
-        public static void WriteMessageid(IDataAccumulator<byte> accumulator, int messageid)
-        {
-            //Alloc buffer for message id + the message id header
-            Span<byte> buffer = stackalloc byte[sizeof(int) + 1];
-
-            //Set 1st byte as message id
-            buffer[0] = (byte)HeaderCommand.MessageId;
-
-            //Write the message id as a big-endian message
-            BinaryPrimitives.WriteInt32BigEndian(buffer[1..], messageid);
-            
-            //Write the header and message id + the trailing termination
-            accumulator.Append(buffer);
-
-            WriteTermination(accumulator);
-        }
-       
-
-        /// <summary>
-        /// Alloctes a random integer to use as a message id
-        /// </summary>
-        public static int RandomMessageId => RandomNumberGenerator.GetInt32(1, int.MaxValue);
-
-        /// <summary>
-        /// Gets the remaining data after the current position of the stream.
-        /// </summary>
-        /// <param name="response">The stream to segment</param>
-        /// <returns>The remaining data segment</returns>
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static ReadOnlySpan<byte> GetRemainingData(VnMemoryStream response)
-        {
-            return response.AsSpan()[(int)response.Position..];
-        }
-
-        /// <summary>
-        /// Reads the next available line from the response message
-        /// </summary>
-        /// <param name="response"></param>
-        /// <returns>The read line</returns>
-        public static ReadOnlySpan<byte> ReadLine(VnMemoryStream response)
-        {
-            //Get the span from the current stream position to end of the stream
-            ReadOnlySpan<byte> line = GetRemainingData(response);
-            //Search for next line termination
-            int index = line.IndexOf(Termination.Span);
-            if (index == -1)
-            {
-                return ReadOnlySpan<byte>.Empty;
-            }
-            //Update stream position to end of termination
-            response.Seek(index + Termination.Length, SeekOrigin.Current);
-            //slice up line and exclude the termination
-            return line[..index];
-        }
-
-        /// <summary>
-        /// Parses headers from the request stream, stores headers from the buffer into the 
-        /// header collection
-        /// </summary>
-        /// <param name="vms">The FBM packet buffer</param>
-        /// <param name="buffer">The header character buffer to write headers to</param>
-        /// <param name="headers">The collection to store headers in</param>
-        /// <param name="encoding">The encoding type used to deocde header values</param>
-        /// <returns>The results of the parse operation</returns>
-        internal static HeaderParseError ParseHeaders(VnMemoryStream vms, in FBMHeaderBuffer buffer, ICollection<FBMMessageHeader> headers, Encoding encoding)
-        {
-            HeaderParseError status = HeaderParseError.None;
-            
-            //Get a sliding window writer over the enitre buffer
-            ForwardOnlyWriter<char> writer = new(buffer.GetSpan());
-
-            //Accumulate headers
-            while (true)
-            {
-                //Read the next line from the current stream
-                ReadOnlySpan<byte> line = ReadLine(vms);
-
-                if (line.IsEmpty)
-                {
-                    //Done reading headers
-                    break;
-                }
-
-                //Read the header command from the next line
-                HeaderCommand cmd = GetHeaderCommand(line);
-
-                //Write the next header value from the line to the remaining space in the buffer
-                ERRNO charsRead = GetHeaderValue(line, writer.Remaining, encoding);
-
-                if (charsRead < 0)
-                {
-                    //Out of buffer space
-                    status |= HeaderParseError.HeaderOutOfMem;
-                    break;
-                }
-                else if (!charsRead)
-                {
-                    //Invalid header
-                    status |= HeaderParseError.InvalidHeaderRead;
-                }
-                else
-                {
-                    //Use the writer to capture the offset, and the character size
-                    FBMMessageHeader header = new(buffer, cmd, writer.Written, (int)charsRead);
-
-                    //Store header as a read-only sequence
-                    headers.Add(header);
-
-                    //Advance the writer
-                    writer.Advance(charsRead);
-                }
-            }
-            return status;
-        }
-
-        /// <summary>
-        /// Gets a <see cref="HeaderCommand"/> enum from the first byte of the message
-        /// </summary>
-        /// <param name="line"></param>
-        /// <returns>The <see cref="HeaderCommand"/> enum value from hte first byte of the message</returns>
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static HeaderCommand GetHeaderCommand(ReadOnlySpan<byte> line)
-        {
-            return (HeaderCommand)line[0];
-        }
-
-        /// <summary>
-        /// Gets the value of the header following the colon bytes in the specifed
-        /// data message data line
-        /// </summary>
-        /// <param name="line">The message header line to get the value of</param>
-        /// <param name="output">The output character buffer to write characters to</param>
-        /// <param name="encoding">The encoding to decode the specified data with</param>
-        /// <returns>The number of characters encoded or -1 if the output buffer is too small</returns>
-        public static ERRNO GetHeaderValue(ReadOnlySpan<byte> line, Span<char> output, Encoding encoding)
-        {
-            //Get the data following the header byte
-            ReadOnlySpan<byte> value = line[1..];
-            //Calculate the character account
-            int charCount = encoding.GetCharCount(value);
-            //Determine if the output buffer is large enough
-            if (charCount > output.Length)
-            {
-                return -1;
-            }
-            //Decode the characters and return the char count
-            _ = encoding.GetChars(value, output);
-            return charCount;
-        }
-      
-
-        /// <summary>
-        /// Ends the header section of the request and appends the message body to 
-        /// the end of the request
-        /// </summary>
-        /// <param name="buffer"></param>
-        /// <param name="body">The message body to send with request</param>
-        /// <exception cref="OutOfMemoryException"></exception>
-        public static void WriteBody(IDataAccumulator<byte> buffer, ReadOnlySpan<byte> body)
-        {
-            //start with termination
-            WriteTermination(buffer);
-            //Write the body
-            buffer.Append(body);
-        }
-
-
-        /// <summary>
-        /// Rounds the requested byte size up to the 1kb 
-        /// number of bytes
-        /// </summary>
-        /// <param name="byteSize">The number of bytes to get the rounded 1kb size of</param>
-        /// <returns>The number of bytes equivalent to the requested byte size rounded to the next 1kb size</returns>
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static nint ToNearestKb(nint byteSize)
-        {
-            //Get page count by dividing count by number of pages
-            nint kbs = (nint)Math.Ceiling(byteSize / (double)1024);
-
-            //Multiply back to page sizes
-            return kbs * 1024;
-        }
-
-
-        /// <summary>
-        /// Writes a line termination to the message buffer
-        /// </summary>
-        /// <param name="buffer"></param>
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static void WriteTermination(IDataAccumulator<byte> buffer) => buffer.Append(Termination.Span);
-
-        /// <summary>
-        /// Appends an arbitrary header to the current request buffer
-        /// </summary>
-        /// <param name="buffer"></param>
-        /// <param name="header">The <see cref="HeaderCommand"/> of the header</param>
-        /// <param name="value">The value of the header</param>
-        /// <param name="encoding">Encoding to use when writing character message</param>
-        /// <exception cref="ArgumentException"></exception>
-        public static void WriteHeader(IDataAccumulator<byte> buffer, byte header, ReadOnlySpan<char> value, Encoding encoding)
-        {
-            //Write header command enum value
-            buffer.Append(header);
-            //Convert the characters to binary and write to the buffer
-            int written = encoding.GetBytes(value, buffer.Remaining);
-            //Advance the buffer
-            buffer.Advance(written);
-            //Write termination (0)
-            WriteTermination(buffer);
-        }
-    }
-}