switch to rolling logfiles (2x 64kb per log type)

Author: Trolldemorted

Signal-Windows.Lib/SignalLogging.cs

@@ -93,23 +93,41 @@ public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Except
         }
     }
 
-    class SignalFileLoggerProvider : ILoggerProvider
+    public class SignalFileLoggerProvider : ILoggerProvider
     {
+        private static string UILog = ApplicationData.Current.LocalCacheFolder.Path + @"\Signal-Windows.ui.log";
         private readonly string Filename;
+        private readonly string OldFilename;
         private readonly string Prefix;
-        private StreamWriter Writer;
-        private object Lock = new object();
+        private const int MaxLogSize = 64 * 1024;
+        private static object Lock = new object();
 
         public SignalFileLoggerProvider(string filename, string prefix)
         {
             Filename = filename;
+            OldFilename = Filename + ".old";
             Prefix = prefix;
-            Open();
         }
 
-        public void Open()
+        public void TruncateLog()
         {
-            Writer = File.CreateText(Filename);
+            try
+            {
+                var length = new FileInfo(Filename).Length;
+                if (length > MaxLogSize)
+                {
+                    if (File.Exists(OldFilename))
+                    {
+                        File.Delete(OldFilename);
+                    }
+                    File.Move(Filename, OldFilename);
+                    File.AppendAllText(Filename, $"{DateTime.UtcNow.ToString("s")} [SignalFileLoggerProvider] truncated log file\n");
+                }
+            }
+            catch (Exception e)
+            {
+                Debug.WriteLine(string.Format("SignalFileLoggerProvider failed to truncate file: {0}", e));
+            }
         }
 
         public void Log(string line)
@@ -118,10 +136,10 @@ public void Log(string line)
             {
                 try
                 {
-                    Writer.WriteLine($"{DateTime.UtcNow.ToString("s")} [{Prefix}] {line}");
-                    Writer.Flush();
+                    TruncateLog();
+                    File.AppendAllText(Filename, $"{DateTime.UtcNow.ToString("s")} [{Prefix}] {line}\n");
                 }
-                catch(Exception e)
+                catch (Exception e)
                 {
                     Debug.WriteLine(string.Format("SignalFileLoggerProvider failed to write: {0}", e));
                 }
@@ -135,10 +153,20 @@ public ILogger CreateLogger(string categoryName)
 
         public void Dispose()
         {
-            lock(Lock)
+        }
+
+        public static void ForceAddUILog(string msg)
+        {
+            lock (Lock)
             {
-                Writer?.Dispose();
-                Writer = null;
+                try
+                {
+                    File.AppendAllText(UILog, msg);
+                }
+                catch (Exception e)
+                {
+                    Debug.WriteLine(string.Format("SignalFileLoggerProvider failed to write: {0}", e));
+                }
             }
         }
     }

Signal-Windows/App.xaml.cs

@@ -33,7 +33,7 @@ namespace Signal_Windows
     sealed partial class App : Application
     {
         private static App Instance;
-        private readonly ILogger Logger = LibsignalLogging.CreateLogger<App>();
+        private static ILogger Logger = LibsignalLogging.CreateLogger<App>();
         public static string URL = "https://textsecure-service.whispersystems.org";
         public static SignalServiceUrl[] ServiceUrls = new SignalServiceUrl[] { new SignalServiceUrl(URL, null) };
         public static StorageFolder LocalCacheFolder = ApplicationData.Current.LocalCacheFolder;
@@ -47,7 +47,7 @@ sealed partial class App : Application
 
         static App()
         {
-            // TODO enforce these have begun before initializing
+            // TODO enforce these have begun before initializing and ensure the logger is working
             Task.Run(() => { SignalDBContext.Migrate(); });
             Task.Run(() => { LibsignalDBContext.Migrate(); });
         }
@@ -57,6 +57,7 @@ static App()
         /// </summary>
         public App()
         {
+            SignalFileLoggerProvider.ForceAddUILog(Utils.GetAppStartMessage());
             Instance = this;
             SignalLogging.SetupLogging(true);
             this.InitializeComponent();

Signal-Windows/Utils.cs

@@ -6,6 +6,7 @@
 using System.Diagnostics;
 using System.Globalization;
 using System.Threading.Tasks;
+using Windows.ApplicationModel;
 using Windows.Foundation;
 using Windows.Foundation.Metadata;
 using Windows.UI;
@@ -263,6 +264,16 @@ public static String BytesToString(long byteCount) //https://stackoverflow.com/a
             return (Math.Sign(byteCount) * num).ToString() + suf[place];
         }
 
+
+        public static string GetAppStartMessage()
+        {
+            var version = Package.Current.Id.Version;
+            return
+                "-------------------------------------------------\n" +
+                String.Format("    Signal-Windows {0}.{1}.{2}.{3} starting\n", version.Major, version.Minor, version.Build, version.Revision) +
+                "-------------------------------------------------\n";
+        }
+
         public static string GetCountryCode(string ISO3166) //https://stackoverflow.com/questions/34837436/uwp-get-country-phone-number-prefix
         {
             var dictionary = new Dictionary<string, string>();