A checkbox that could not say STARTTLS, and three actions with no button

External accounts. The "Use SSL/TLS" checkbox on an external POP3 download
account was a boolean over a four-valued setting, and the mapping was lossy in
both directions: InterfaceFetchAccount::get_UseSSL is ConnectionSecurity ==
CSSSL, and put_UseSSL writes CSSSL or CSNone. So an account already set to
STARTTLS read back as unticked, and saving that dialog rewrote it to implicit
TLS. Implicit TLS on port 110 does not connect, which made STARTTLS effectively
unreachable from the GUI for exactly the providers that require it.

The server has supported all four values on this path throughout:
POP3ClientConnection sends CAPA, issues STLS, and on "STARTTLS required"
abandons the download with a log line when the far end does not advertise it.
The field is now that choice, worded with the port each option implies, because
changing the security without changing the port is the commonest way an
external account is configured and then never downloads anything.

While doing it, combo columns in every collection editor stopped rendering
their raw enum number. A grid cell reading "1" beside a dialog reading
"SSL/TLS" is not a cosmetic problem: it is the difference between a list of
accounts you can scan for the unencrypted row and one you cannot.

Database tuning. NumberOfConnections, ConnectionAttempts and
ConnectionAttemptsDelay live in [Database] and had no editor anywhere. The rest
of that section decides whether the server starts at all and stays with the
setup wizard; these three decide how it behaves once connected, and a server
that cannot reach its database for the first half-minute after a reboot had no
way to lengthen the window without hand-editing. The pool size card reads the
configured database type and says outright, before you change it, that the
built-in database forces the value to 1 whatever is set - which is what
IniFileSettings.cpp does and what no GUI has ever admitted.

That needed a section-aware INI row. IniFeatureStore writes [Settings] only, so
a [Database] key edited through the existing row type would have been written
into [Settings], where the server never looks - saved, correct on reload, and
inert. ReadFrom/WriteTo exist to make that mistake impossible to make quietly.

Three actions that existed over COM and nowhere else. MessageIndexing.Index()
and .Clear() are now buttons on Performance > Indexing, and
Utilities.PerformMaintenance(eUpdateIMAPFolderUID) is a button on the IMAP tab.

The indexing buttons say what they actually do rather than what they look like
they do. MessageIndexer::IndexNow() does not index - it sets an event that a
worker thread waits on - and that worker is only started when indexing is
enabled. So "Index now" with indexing switched off would signal a thread that
is not running and report success having done nothing; it now checks first and
says so. And the counts it reports are labelled as the state before the pass,
because they are: the pass has not happened when the button returns. Reporting
them as "now" would have looked exactly like a stuck indexer.

The folder-UID repair is worth having a button because of what it repairs:
Maintenance::RecalculateFolderUID_ raises each IMAP folder's UID counter to the
highest UID the folder actually holds. A counter that has fallen behind hands
the same UID out twice, and a client that caches by UID then shows one message
in place of another. It never lowers a counter, so it cannot cause the fault it
fixes - and the card says so, because an administrator will not run a repair
they cannot reason about.

Control Panel: 533 passed, 0 failed. Server unchanged.

Author: chrisholloway5

hmailserver/source/Tools/ControlPanel/Services/IniFeatureStore.cs

@@ -110,14 +110,37 @@ public void Write(string key, string value)
 
       public void WriteBool(string key, bool value) => Write(key, value ? "1" : "0");
 
+      /// <summary>
+      /// Reads a value from a named section rather than from [Settings].
+      ///
+      /// Most of hMailServer.INI is [Settings], which is why this class defaults to
+      /// it - but not all of it, and a page that edits [Database] or [Directories]
+      /// through Read() above would write keys of the right name into a section the
+      /// server never looks at. That is the worst shape of bug this project has:
+      /// the value appears saved, reads back correctly on the next visit, and does
+      /// nothing.
+      /// </summary>
+      public string ReadFrom(string section, string key, string defaultValue = "")
+      {
+         if (!IsAvailable)
+            return defaultValue;
+         var buffer = new StringBuilder(2048);
+         GetPrivateProfileString(section, key, defaultValue, buffer, buffer.Capacity, IniPath);
+         return buffer.ToString();
+      }
+
+      /// <summary>Writes a value to a named section. See <see cref="ReadFrom"/>.</summary>
+      public void WriteTo(string section, string key, string value)
+      {
+         if (!IsAvailable)
+            throw new InvalidOperationException("hMailServer.INI was not found on this machine.");
+         WritePrivateProfileString(section, key, value, IniPath);
+      }
+
       /// <summary>Reads the configured log folder from the [Directories] section.</summary>
       public string GetLogFolder()
       {
-         if (!IsAvailable)
-            return null;
-         var buffer = new StringBuilder(1024);
-         GetPrivateProfileString("Directories", "LogFolder", "", buffer, buffer.Capacity, IniPath);
-         string folder = buffer.ToString();
+         string folder = ReadFrom("Directories", "LogFolder", "");
          return string.IsNullOrWhiteSpace(folder) ? null : folder;
       }
    }

hmailserver/source/Tools/ControlPanel/Services/SettingsSearchIndex.g.cs

@@ -201,6 +201,8 @@ public static partial class SettingsSearchIndex
          new SettingEntry("Account cache TTL (seconds)", "Cache.AccountCacheTTL", "performance"),
          new SettingEntry("Alias cache max size (KB, resets at service restart)", "Cache.AliasCacheMaxSizeKb", "performance"),
          new SettingEntry("Alias cache TTL (seconds)", "Cache.AliasCacheTTL", "performance"),
+         new SettingEntry("Attempts to reach the database at start-up", "ConnectionAttempts", "performance"),
+         new SettingEntry("Connections in the pool", "NumberOfConnections", "performance"),
          new SettingEntry("Distribution-list cache max size (KB, resets at service restart)", "Cache.DistributionListCacheMaxSizeKb", "performance"),
          new SettingEntry("Distribution-list cache TTL (seconds)", "Cache.DistributionListCacheTTL", "performance"),
          new SettingEntry("Domain cache max size (KB, resets at service restart)", "Cache.DomainCacheMaxSizeKb", "performance"),
@@ -213,6 +215,7 @@ public static partial class SettingsSearchIndex
          new SettingEntry("Max parallel external POP3 fetch threads (restart required)", "MaxNumberOfExternalFetchThreads", "performance"),
          new SettingEntry("Messages per full-index pass", "IndexerFullLimit", "performance"),
          new SettingEntry("Messages per quick-index pass", "IndexerQuickLimit", "performance"),
+         new SettingEntry("Seconds between those attempts", "ConnectionAttemptsDelay", "performance"),
          new SettingEntry("TCP/IP threads", "TCPIPThreads", "performance"),
          new SettingEntry("Worker thread priority (stored, but the server does not use it)", "WorkerThreadPriority", "performance"),
          new SettingEntry("ACL (shared folder permissions)", "IMAPACLEnabled", "protocols"),

hmailserver/source/Tools/ControlPanel/Views/CollectionEditorView.cs

@@ -183,7 +183,16 @@ private void Build()
             var col = new DataGridTextColumn
             {
                Header = f.Label,
-               Binding = new System.Windows.Data.Binding($"Values[{prop}]") { Converter = CellConverter.Instance },
+               // A Combo column stores the enum's number, and a grid cell reading
+               // "1" where the dialog above it reads "SSL/TLS" is not a display
+               // detail - it is the difference between a list an administrator can
+               // scan for the unencrypted row and one they cannot.
+               Binding = new System.Windows.Data.Binding($"Values[{prop}]")
+               {
+                  Converter = f.Kind == FieldKind.Combo && f.Options != null
+                     ? new CellConverter(f.Options)
+                     : CellConverter.Instance
+               },
                Width = double.IsNaN(f.GridWidth)
                   ? new DataGridLength(1, DataGridLengthUnitType.Star)
                   : new DataGridLength(f.GridWidth)
@@ -383,8 +392,48 @@ internal static string FormatCell(object v)
 
       private sealed class CellConverter : System.Windows.Data.IValueConverter
       {
+         /// <summary>Option labels for a Combo column, or null for every other kind.</summary>
+         private readonly (int Value, string Label)[] options_;
+
+         private CellConverter()
+         {
+         }
+
+         public CellConverter((int Value, string Label)[] options) => options_ = options;
+
          public static readonly CellConverter Instance = new();
-         public object Convert(object value, Type t, object p, CultureInfo c) => FormatCell(value);
+
+         public object Convert(object value, Type t, object p, CultureInfo c)
+         {
+            if (options_ != null && value != null)
+            {
+               // A value with no matching option falls through to the number
+               // rather than being shown as blank or as the first option: an
+               // enum the GUI does not know about is a real thing to notice,
+               // and blanking it would hide it.
+               try
+               {
+                  int number = System.Convert.ToInt32(value, CultureInfo.InvariantCulture);
+                  foreach ((int Value, string Label) option in options_)
+                  {
+                     if (option.Value == number)
+                        return option.Label;
+                  }
+               }
+               catch (FormatException)
+               {
+               }
+               catch (InvalidCastException)
+               {
+               }
+               catch (OverflowException)
+               {
+               }
+            }
+
+            return FormatCell(value);
+         }
+
          public object ConvertBack(object value, Type t, object p, CultureInfo c) => value;
       }
    }

hmailserver/source/Tools/ControlPanel/Views/CollectionSpecs.cs

@@ -16,6 +16,22 @@ public static class CollectionSpecs
       private static dynamic AntiSpam => ServerSession.Current.Application.Settings.AntiSpam;
       private static dynamic Settings => ServerSession.Current.Application.Settings;
 
+      /// <summary>
+      /// hMailServer's eConnectionSecurity, in the order the enum declares it, and
+      /// worded the same way the SSL/TLS and Delivery pages word it so the same
+      /// choice does not read as two different things in two places. The wording
+      /// carries the port each one implies, because choosing the security without
+      /// changing the port is the single commonest way an external account is
+      /// configured and then never downloads anything.
+      /// </summary>
+      private static readonly (int Value, string Label)[] ConnectionSecurityOptions =
+      {
+         (0, "None - no encryption (port 110)"),
+         (1, "SSL/TLS - encrypted from the first byte (port 995)"),
+         (2, "STARTTLS, optional - upgrade if offered, continue in the clear if not (port 110)"),
+         (3, "STARTTLS, required - refuse to download unless the upgrade succeeds (port 110)")
+      };
+
       public static CollectionEditorView SurblServers() => new(new CollectionSpec
       {
          Title = "SURBL servers",
@@ -167,7 +183,8 @@ private static dynamic OpenAccount(string domainName, string address)
       public static CollectionEditorView FetchAccounts(string domainName, string address) => new(new CollectionSpec
       {
          Title = "External accounts",
-         Subtitle = "POP3 mailboxes hMailServer downloads mail from on behalf of this account.",
+         Subtitle = "POP3 mailboxes hMailServer downloads mail from on behalf of this account. "
+                    + "Connection security and port go together: SSL/TLS on 995, STARTTLS on 110.",
          ItemNoun = "external account",
          GetCollection = () =>
          {
@@ -186,7 +203,28 @@ private static dynamic OpenAccount(string domainName, string address)
             new FieldSpec { Prop = "Password", Label = "Password", Kind = FieldKind.Password, ShowInGrid = false, Default = "" },
             new FieldSpec { Prop = "MinutesBetweenFetch", Label = "Minutes between downloads", Kind = FieldKind.Number, ShowInGrid = false, Default = 15 },
             new FieldSpec { Prop = "DaysToKeepMessages", Label = "Days to keep on server (0 = delete after download)", Kind = FieldKind.Number, ShowInGrid = false, Default = 0 },
-            new FieldSpec { Prop = "UseSSL", Label = "Use SSL/TLS", Kind = FieldKind.Bool, ShowInGrid = false, Default = false },
+            // Was a "Use SSL/TLS" checkbox, which could not express STARTTLS at
+            // all. The COM property behind that checkbox is UseSSL, and its
+            // getter is ConnectionSecurity == CSSSL while its setter writes
+            // CSSSL or CSNone - so an account already set to STARTTLS read back
+            // as unticked, and ticking anything on that dialog rewrote it to
+            // implicit TLS on the next save. Implicit TLS on port 110 does not
+            // connect, which made STARTTLS effectively unreachable from the GUI
+            // for the very providers that require it.
+            //
+            // The server has supported all four values on the fetch path
+            // throughout: POP3ClientConnection sends CAPA, issues STLS, and on
+            // CSSTARTTLSRequired abandons the download with a log line when the
+            // far end does not advertise STLS.
+            new FieldSpec
+            {
+               Prop = "ConnectionSecurity",
+               Label = "Connection security",
+               Kind = FieldKind.Combo,
+               Options = ConnectionSecurityOptions,
+               GridWidth = 150,
+               Default = 0
+            },
             new FieldSpec { Prop = "UseAntiSpam", Label = "Run anti-spam on downloaded mail", Kind = FieldKind.Bool, ShowInGrid = false, Default = true },
             new FieldSpec { Prop = "UseAntiVirus", Label = "Run anti-virus on downloaded mail", Kind = FieldKind.Bool, ShowInGrid = false, Default = true }
          }