move factory logic to DatabaseFactory so the test project does not ne…

…ed to reference all sys-calls used for reading files

src/libraries/System.Console/src/System.Console.csproj

@@ -163,6 +163,7 @@
     <Compile Include="System\TermInfo.cs" />
     <Compile Include="System\TermInfo.WellKnownStrings.cs" />
     <Compile Include="System\TermInfo.Database.cs" />
+    <Compile Include="System\TermInfo.DatabaseFactory.cs" />
     <Compile Include="System\IO\StdInReader.cs" />
     <Compile Include="System\IO\SyncTextReader.Unix.cs" />
     <Compile Include="$(CoreLibSharedDir)System\IO\PersistedFiles.Unix.cs"

src/libraries/System.Console/src/System/ConsolePal.Unix.cs

@@ -961,7 +961,7 @@ internal sealed class TerminalFormatStrings
         {
             /// <summary>Gets the lazily-initialized terminal information for the terminal.</summary>
             public static TerminalFormatStrings Instance { get { return s_instance.Value; } }
-            private static readonly Lazy<TerminalFormatStrings> s_instance = new Lazy<TerminalFormatStrings>(() => new TerminalFormatStrings(TermInfo.Database.ReadActiveDatabase()));
+            private static readonly Lazy<TerminalFormatStrings> s_instance = new Lazy<TerminalFormatStrings>(() => new TerminalFormatStrings(TermInfo.DatabaseFactory.ReadActiveDatabase()));
 
             /// <summary>The format string to use to change the foreground color.</summary>
             public readonly string? Foreground;

src/libraries/System.Console/src/System/TermInfo.Database.cs

@@ -4,10 +4,7 @@
 using System.Buffers.Binary;
 using System.Collections.Generic;
 using System.Diagnostics;
-using System.Diagnostics.CodeAnalysis;
-using System.IO;
 using System.Text;
-using Microsoft.Win32.SafeHandles;
 
 namespace System;
 
@@ -42,7 +39,7 @@ internal sealed class Database
         /// <summary>Initializes the database instance.</summary>
         /// <param name="term">The name of the terminal.</param>
         /// <param name="data">The data from the terminfo file.</param>
-        private Database(string term, byte[] data)
+        internal Database(string term, byte[] data)
         {
             _term = term;
             _data = data;
@@ -84,120 +81,6 @@ private Database(string term, byte[] data)
         /// <summary>The name of the associated terminfo, if any.</summary>
         public string Term { get { return _term; } }
 
-        /// <summary>Read the database for the current terminal as specified by the "TERM" environment variable.</summary>
-        /// <returns>The database, or null if it could not be found.</returns>
-        internal static Database? ReadActiveDatabase()
-        {
-            string? term = Environment.GetEnvironmentVariable("TERM");
-            return !string.IsNullOrEmpty(term) ? ReadDatabase(term) : null;
-        }
-
-        /// <summary>
-        /// The default locations in which to search for terminfo databases.
-        /// This is the ordering of well-known locations used by ncurses.
-        /// </summary>
-        private static readonly string[] _terminfoLocations = new string[] {
-            "/etc/terminfo",
-            "/lib/terminfo",
-            "/usr/share/terminfo",
-            "/usr/share/misc/terminfo",
-            "/usr/local/share/terminfo"
-        };
-
-        /// <summary>Read the database for the specified terminal.</summary>
-        /// <param name="term">The identifier for the terminal.</param>
-        /// <returns>The database, or null if it could not be found.</returns>
-        private static Database? ReadDatabase(string term)
-        {
-            // This follows the same search order as prescribed by ncurses.
-            Database? db;
-
-            // First try a location specified in the TERMINFO environment variable.
-            string? terminfo = Environment.GetEnvironmentVariable("TERMINFO");
-            if (!string.IsNullOrWhiteSpace(terminfo) && (db = ReadDatabase(term, terminfo)) != null)
-            {
-                return db;
-            }
-
-            // Then try in the user's home directory.
-            string? home = PersistedFiles.GetHomeDirectory();
-            if (!string.IsNullOrWhiteSpace(home) && (db = ReadDatabase(term, home + "/.terminfo")) != null)
-            {
-                return db;
-            }
-
-            // Then try a set of well-known locations.
-            foreach (string terminfoLocation in _terminfoLocations)
-            {
-                if ((db = ReadDatabase(term, terminfoLocation)) != null)
-                {
-                    return db;
-                }
-            }
-
-            // Couldn't find one
-            return null;
-        }
-
-        /// <summary>Attempt to open as readonly the specified file path.</summary>
-        /// <param name="filePath">The path to the file to open.</param>
-        /// <param name="fd">If successful, the opened file descriptor; otherwise, -1.</param>
-        /// <returns>true if the file was successfully opened; otherwise, false.</returns>
-        private static bool TryOpen(string filePath, [NotNullWhen(true)] out SafeFileHandle? fd)
-        {
-            fd = Interop.Sys.Open(filePath, Interop.Sys.OpenFlags.O_RDONLY | Interop.Sys.OpenFlags.O_CLOEXEC, 0);
-            if (fd.IsInvalid)
-            {
-                // Don't throw in this case, as we'll be polling multiple locations looking for the file.
-                fd = null;
-                return false;
-            }
-
-            return true;
-        }
-
-        /// <summary>Read the database for the specified terminal from the specified directory.</summary>
-        /// <param name="term">The identifier for the terminal.</param>
-        /// <param name="directoryPath">The path to the directory containing terminfo database files.</param>
-        /// <returns>The database, or null if it could not be found.</returns>
-        private static Database? ReadDatabase(string? term, string? directoryPath)
-        {
-            if (string.IsNullOrEmpty(term) || string.IsNullOrEmpty(directoryPath))
-            {
-                return null;
-            }
-
-            Span<char> stackBuffer = stackalloc char[256];
-            SafeFileHandle? fd;
-            if (!TryOpen(string.Create(null, stackBuffer, $"{directoryPath}/{term[0]}/{term}"), out fd) &&       // /directory/termFirstLetter/term      (Linux)
-                !TryOpen(string.Create(null, stackBuffer, $"{directoryPath}/{(int)term[0]:X}/{term}"), out fd))  // /directory/termFirstLetterAsHex/term (Mac)
-            {
-                return null;
-            }
-
-            using (fd)
-            {
-                // Read in all of the terminfo data
-                long termInfoLength = Interop.CheckIo(Interop.Sys.LSeek(fd, 0, Interop.Sys.SeekWhence.SEEK_END)); // jump to the end to get the file length
-                Interop.CheckIo(Interop.Sys.LSeek(fd, 0, Interop.Sys.SeekWhence.SEEK_SET)); // reset back to beginning
-                const int MaxTermInfoLength = 4096; // according to the term and tic man pages, 4096 is the terminfo file size max
-                const int HeaderLength = 12;
-                if (termInfoLength <= HeaderLength || termInfoLength > MaxTermInfoLength)
-                {
-                    throw new InvalidOperationException(SR.IO_TermInfoInvalid);
-                }
-
-                byte[] data = new byte[(int)termInfoLength];
-                if (ConsolePal.Read(fd, data) != data.Length)
-                {
-                    throw new InvalidOperationException(SR.IO_TermInfoInvalid);
-                }
-
-                // Create the database from the data
-                return new Database(term, data);
-            }
-        }
-
         /// <summary>The offset into data where the names section begins.</summary>
         private const int NamesOffset = 12; // comes right after the header, which is always 12 bytes
 

src/libraries/System.Console/src/System/TermInfo.DatabaseFactory.cs

@@ -0,0 +1,128 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Diagnostics.CodeAnalysis;
+using System.IO;
+using Microsoft.Win32.SafeHandles;
+
+namespace System;
+
+internal static partial class TermInfo
+{
+    internal sealed class DatabaseFactory
+    {
+        /// <summary>
+        /// The default locations in which to search for terminfo databases.
+        /// This is the ordering of well-known locations used by ncurses.
+        /// </summary>
+        private static readonly string[] _terminfoLocations = new string[] {
+            "/etc/terminfo",
+            "/lib/terminfo",
+            "/usr/share/terminfo",
+            "/usr/share/misc/terminfo",
+            "/usr/local/share/terminfo"
+        };
+
+        /// <summary>Read the database for the current terminal as specified by the "TERM" environment variable.</summary>
+        /// <returns>The database, or null if it could not be found.</returns>
+        internal static Database? ReadActiveDatabase()
+        {
+            string? term = Environment.GetEnvironmentVariable("TERM");
+            return !string.IsNullOrEmpty(term) ? ReadDatabase(term) : null;
+        }
+
+        /// <summary>Read the database for the specified terminal.</summary>
+        /// <param name="term">The identifier for the terminal.</param>
+        /// <returns>The database, or null if it could not be found.</returns>
+        private static Database? ReadDatabase(string term)
+        {
+            // This follows the same search order as prescribed by ncurses.
+            Database? db;
+
+            // First try a location specified in the TERMINFO environment variable.
+            string? terminfo = Environment.GetEnvironmentVariable("TERMINFO");
+            if (!string.IsNullOrWhiteSpace(terminfo) && (db = ReadDatabase(term, terminfo)) != null)
+            {
+                return db;
+            }
+
+            // Then try in the user's home directory.
+            string? home = PersistedFiles.GetHomeDirectory();
+            if (!string.IsNullOrWhiteSpace(home) && (db = ReadDatabase(term, home + "/.terminfo")) != null)
+            {
+                return db;
+            }
+
+            // Then try a set of well-known locations.
+            foreach (string terminfoLocation in _terminfoLocations)
+            {
+                if ((db = ReadDatabase(term, terminfoLocation)) != null)
+                {
+                    return db;
+                }
+            }
+
+            // Couldn't find one
+            return null;
+        }
+
+        /// <summary>Attempt to open as readonly the specified file path.</summary>
+        /// <param name="filePath">The path to the file to open.</param>
+        /// <param name="fd">If successful, the opened file descriptor; otherwise, -1.</param>
+        /// <returns>true if the file was successfully opened; otherwise, false.</returns>
+        private static bool TryOpen(string filePath, [NotNullWhen(true)] out SafeFileHandle? fd)
+        {
+            fd = Interop.Sys.Open(filePath, Interop.Sys.OpenFlags.O_RDONLY | Interop.Sys.OpenFlags.O_CLOEXEC, 0);
+            if (fd.IsInvalid)
+            {
+                // Don't throw in this case, as we'll be polling multiple locations looking for the file.
+                fd = null;
+                return false;
+            }
+
+            return true;
+        }
+
+        /// <summary>Read the database for the specified terminal from the specified directory.</summary>
+        /// <param name="term">The identifier for the terminal.</param>
+        /// <param name="directoryPath">The path to the directory containing terminfo database files.</param>
+        /// <returns>The database, or null if it could not be found.</returns>
+        private static Database? ReadDatabase(string? term, string? directoryPath)
+        {
+            if (string.IsNullOrEmpty(term) || string.IsNullOrEmpty(directoryPath))
+            {
+                return null;
+            }
+
+            Span<char> stackBuffer = stackalloc char[256];
+            SafeFileHandle? fd;
+            if (!TryOpen(string.Create(null, stackBuffer, $"{directoryPath}/{term[0]}/{term}"), out fd) &&       // /directory/termFirstLetter/term      (Linux)
+                !TryOpen(string.Create(null, stackBuffer, $"{directoryPath}/{(int)term[0]:X}/{term}"), out fd))  // /directory/termFirstLetterAsHex/term (Mac)
+            {
+                return null;
+            }
+
+            using (fd)
+            {
+                // Read in all of the terminfo data
+                long termInfoLength = Interop.CheckIo(Interop.Sys.LSeek(fd, 0, Interop.Sys.SeekWhence.SEEK_END)); // jump to the end to get the file length
+                Interop.CheckIo(Interop.Sys.LSeek(fd, 0, Interop.Sys.SeekWhence.SEEK_SET)); // reset back to beginning
+                const int MaxTermInfoLength = 4096; // according to the term and tic man pages, 4096 is the terminfo file size max
+                const int HeaderLength = 12;
+                if (termInfoLength <= HeaderLength || termInfoLength > MaxTermInfoLength)
+                {
+                    throw new InvalidOperationException(SR.IO_TermInfoInvalid);
+                }
+
+                byte[] data = new byte[(int)termInfoLength];
+                if (ConsolePal.Read(fd, data) != data.Length)
+                {
+                    throw new InvalidOperationException(SR.IO_TermInfoInvalid);
+                }
+
+                // Create the database from the data
+                return new Database(term, data);
+            }
+        }
+    }
+}