fixed bug with matching commands accross segments

Author: cosullivan

Examples/SampleApp/Examples/SessionTracingExample.cs

@@ -30,7 +30,7 @@ public static void Run()
 
             var serverTask = server.StartAsync(_cancellationTokenSource.Token);
 
-            SampleMailClient.Send();
+            SampleMailClient.Send(recipients: 1);
 
             serverTask.WaitWithoutException();
         }
@@ -62,7 +62,7 @@ private static void OnResponseException(object sender, SmtpResponseExceptionEven
             if (e.Exception.Properties.ContainsKey("SmtpSession:Buffer"))
             {
                 var buffer = e.Exception.Properties["SmtpSession:Buffer"] as byte[];
-                Console.WriteLine("Unknown Line: {0}", Encoding.UTF8.GetString(buffer));
+                Console.WriteLine("Unrecognized Command: {0}", Encoding.UTF8.GetString(buffer));
             }
         }
 

Examples/SampleApp/Program.cs

@@ -33,6 +33,8 @@ static void Main(string[] args)
 
             //var files = Directory.GetFiles(@"C:\Temp\enron_mail_20150507.tar", "*.*", SearchOption.AllDirectories).ToList();
             //Console.WriteLine(files.OrderByDescending(file => new FileInfo(file).Length).First());
+
+            //new TokenReaderTests().CanCompareAcrossMultipleSegments();
         }
 
         static bool IgnoreCertificateValidationFailureForTestingOnly(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)

Examples/SampleApp/SampleMailClient.cs

@@ -14,13 +14,19 @@ public static void Send(
             string password = null,
             MimeEntity body = null,
             int count = 1,
+            int recipients = 1,
             bool useSsl = false,
             int port = 9025)
         {
             var message = new MimeMessage();
 
             message.From.Add(MailboxAddress.Parse(from ?? "[email protected]"));
-            message.To.Add(MailboxAddress.Parse(to ?? "[email protected]"));
+            
+            for (var i = 0; i < recipients; i++)
+            {
+                message.To.Add(MailboxAddress.Parse(to ?? $"to_{i}@sample.com"));
+            }
+
             message.Subject = subject ?? "Hello";
             message.Body = body ?? new TextPart("plain")
             {

Src/SmtpServer.Tests/SmtpParserTests.cs

@@ -7,7 +7,6 @@
 using SmtpServer.Protocol;
 using SmtpServer.Text;
 using Xunit;
-using static System.Net.Mime.MediaTypeNames;
 
 namespace SmtpServer.Tests
 {

Src/SmtpServer.Tests/TokenReaderTests.cs

@@ -1,4 +1,5 @@
-using System.Text;
+using System;
+using System.Text;
 using SmtpServer.IO;
 using SmtpServer.Text;
 using Xunit;
@@ -19,6 +20,39 @@ static TokenReader CreateReader(params string[] values)
             return new TokenReader(segments.Build());
         }
 
+        [Fact]
+        public void CanCompareAcrossMultipleSegments()
+        {
+            // arrange
+            var reader = CreateReader("A", "BCD", "EF");
+
+            Span<char> match = stackalloc char[6];
+            match[0] = 'A';
+            match[1] = 'B';
+            match[2] = 'C';
+            match[3] = 'D';
+            match[4] = 'E';
+            match[5] = 'F';
+
+            // assert
+            Assert.True(reader.TryMake(TryMakeText, out var text));
+            Assert.False(text.IsSingleSegment);
+
+            // assert
+            Assert.True(text.CaseInsensitiveStringEquals(ref match));
+
+            static bool TryMakeText(ref TokenReader reader)
+            {
+                if (reader.Peek().Kind == TokenKind.Text)
+                {
+                    reader.Skip(TokenKind.Text);
+                    return true;
+                }
+
+                return false;
+            }
+        }
+
         [Fact]
         public void CanTokenizeWord()
         {

Src/SmtpServer/IO/BuffersExtension.cs

@@ -137,7 +137,7 @@ internal static bool CaseInsensitiveStringEquals(this ReadOnlySequence<byte> buf
             {
                 var span = buffer.First.Span;
 
-                return CaseInsensitiveStringEquals(ref span, ref text, 0);
+                return text.Length == span.Length && CaseInsensitiveStringEquals(ref span, ref text, 0);
             }
 
             var i = 0;
@@ -155,16 +155,11 @@ internal static bool CaseInsensitiveStringEquals(this ReadOnlySequence<byte> buf
                 i += span.Length;
             }
 
-            return i > 0;
+            return i == text.Length;
         }
 
         static bool CaseInsensitiveStringEquals(ref ReadOnlySpan<byte> span, ref Span<char> text, int offset)
         {
-            if (text.Length - offset != span.Length)
-            {
-                return false;
-            }
-
             for (var i = 0; i < span.Length; i++)
             {
                 var ch = (char)span[i];

Src/SmtpServer/Protocol/SmtpParser.cs

@@ -283,7 +283,7 @@ public bool TryMakeRcpt(ref TokenReader reader, out SmtpCommand command, out Smt
             {
                 return false;
             }
-            
+
             reader.Skip(TokenKind.Space);
 
             if (TryMakeToLiteral(ref reader) == false)