Util/Logger.cs

   1 //
   2 // Logger.cs
   3 //
   4 // Copyright (C) 2004 Novell, Inc.
   5 //
   6
   7 //
   8 // Permission is hereby granted, free of charge, to any person obtaining a copy
   9 // of this software and associated documentation files (the "Software"), to deal
  10 // in the Software without restriction, including without limitation the rights
  11 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12 // copies of the Software, and to permit persons to whom the Software is
  13 // furnished to do so, subject to the following conditions:
  14 //
  15 // The above copyright notice and this permission notice shall be included in all
  16 // copies or substantial portions of the Software.
  17 //
  18 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24 // SOFTWARE.
  25 //
  26
  27 using System;
  28 using System.Collections;
  29 using System.Text;
  30 using System.IO;
  31 using System.Diagnostics;
  32
  33 namespace Beagle.Util {
  34
  35         public enum LogLevel {
  36                 None,
  37                 Fatal,
  38                 Error,
  39                 Warn,
  40                 Info,
  41                 Debug
  42         }
  43
  44         public class Logger {
  45
  46                 private static Hashtable loggers = new Hashtable ();
  47                 private static TextWriter defaultWriter = null;
  48                 private static bool defaultEcho = true; //false;
  49                 private static string defaultLogName = null;
  50
  51                 // FIXME: The defaultLevel should be something higher
  52                 // than just LogLevel.Debug in the future. Users bitch
  53                 // about disk space.
  54                 private static LogLevel defaultLevel = LogLevel.Debug; //LogLevel.Info
  55
  56                 public static Logger Log {
  57                         get {
  58                                 return Get ("other");
  59                         }
  60                 }
  61
  62                 public static Logger Get (string logName)
  63                 {
  64                         if (loggers.ContainsKey (logName)) {
  65                                 return (Logger)loggers[logName];
  66                         } else {
  67                                 Logger log = new Logger (logName);
  68                                 log.Level = defaultLevel;
  69                                 log.Writer = defaultWriter;
  70                                 log.Echo = defaultEcho;
  71                                 loggers[logName] = log;
  72                                 return log;
  73                         }
  74                 }
  75
  76                 public static LogLevel DefaultLevel {
  77                         get { return defaultLevel; }
  78                         set { defaultLevel = value; }
  79                 }
  80
  81
  82                 public static TextWriter DefaultWriter {
  83                         get { return defaultWriter; }
  84                         set { defaultWriter = value; }
  85                 }
  86
  87                 public static bool DefaultEcho {
  88                         get { return defaultEcho; }
  89                         set { defaultEcho = value; }
  90                 }
  91
  92                 private static object write_lock = new object ();
  93
  94                 private bool levelSet = false;
  95                 private LogLevel level;
  96                 private TextWriter writer = null;
  97                 private bool echo = false;
  98
  99                 private Logger (string name) {
 100                 }
 101
 102                 public LogLevel Level {
 103                         get { lock (this) { return (levelSet) ? level : DefaultLevel; } }
 104                         set { lock (this) { level = value; levelSet = true; } }
 105                 }
 106
 107                 public TextWriter Writer {
 108                         get { return writer; }
 109                         set { writer = value; }
 110                 }
 111
 112                 public bool Echo {
 113                         get { return echo; }
 114                         set { echo = value; }
 115                 }
 116
 117                 // Multiple logs can be merge-sorted via "sort -m log1 log2 ..."
 118                 private string GetStamp ()
 119                 {
 120                         StringBuilder builder = new StringBuilder ();
 121                         builder.AppendFormat ("{0:yy-MM-dd HH.mm.ss.ff} ", DateTime.Now);
 122                         builder.AppendFormat ("{0:00000} ", Process.GetCurrentProcess().Id);
 123                         if (defaultLogName != null) {
 124                                 builder.AppendFormat (defaultLogName);
 125                                 builder.Append (' ');
 126                         }
 127                         return builder.ToString ();
 128                 }
 129
 130                 private void WriteLine (string level, string message) {
 131                         if (Writer != null) {
 132                                 lock (write_lock) {
 133                                         Writer.WriteLine ("{0}{1}: {2}", GetStamp (), level, message);
 134                                         Writer.Flush ();
 135                                 }
 136                         }
 137                         if (Echo)
 138                                 System.Console.WriteLine ("{0}: {1}", level, message);
 139                 }
 140
 141                 public void Debug (string message, params object [] args)
 142                 {
 143                         if (IsDebugEnabled) {
 144                                 WriteLine ("DEBUG", String.Format (message, args));
 145                         }
 146                 }
 147
 148                 public void Debug (Exception e)
 149                 {
 150                         Debug ("{0}", e);
 151                 }
 152
 153                 public void Info (string message, params object [] args)
 154                 {
 155                         if (IsInfoEnabled) {
 156                                 WriteLine ("INFO", String.Format (message, args));
 157                         }
 158                 }
 159
 160                 public void Info (Exception e)
 161                 {
 162                         Info ("{0}", e);
 163                 }
 164
 165                 public void Warn (string message, params object [] args)
 166                 {
 167                         if (IsWarnEnabled) {
 168                                 WriteLine ("WARN", String.Format (message, args));
 169                         }
 170                 }
 171
 172                 public void Warn (Exception e)
 173                 {
 174                         Warn ("{0}", e);
 175                 }
 176
 177                 public void Error (string message, params object [] args)
 178                 {
 179                         if (IsErrorEnabled) {
 180                                 WriteLine ("ERROR", String.Format (message, args));
 181                         }
 182                 }
 183
 184                 public void Error (Exception e)
 185                 {
 186                         Error ("{0}", e);
 187                 }
 188
 189                 public void Fatal (string message, params object [] args)
 190                 {
 191                         if (IsFatalEnabled) {
 192                                 WriteLine ("FATAL", String.Format (message, args));
 193                         }
 194                 }
 195
 196                 public void Fatal (Exception e)
 197                 {
 198                         Fatal ("{0}", e);
 199                 }
 200
 201                 public bool IsDebugEnabled { get { return level >= LogLevel.Debug; } }
 202                 public bool IsInfoEnabled { get { return level >= LogLevel.Info; } }
 203                 public bool IsWarnEnabled { get { return level >= LogLevel.Warn; } }
 204                 public bool IsErrorEnabled { get { return level >= LogLevel.Error;} }
 205                 public bool IsFatalEnabled { get { return level >= LogLevel.Fatal; } }
 206
 207                 ////////////////////////////////////////////////////////////////////////////////
 208
 209                 static private void PruneOldLogs (string path, string instance)
 210                 {
 211                         DateTime magic_date = DateTime.Now.AddDays (-7);
 212                         DirectoryInfo dir = new DirectoryInfo (path);
 213
 214                         foreach (FileInfo file in dir.GetFiles ()) {
 215                                 if (file.Name.StartsWith ("current") || (! file.Name.EndsWith (instance)))
 216                                         continue;
 217
 218                                 int last_dash = file.Name.LastIndexOf ("-");
 219                                 if (last_dash == -1)
 220                                         continue; // skip strange-looking files
 221
 222                                 string date = file.Name.Substring (0, last_dash);
 223
 224                                 try {
 225                                         DateTime log_date;
 226                                         log_date = DateTime.ParseExact (date, "yyyy-MM-dd-HH-mm-ss", null);
 227                                         if (log_date < magic_date)
 228                                                 file.Delete ();
 229                                 } catch (Exception e) { }
 230                         }
 231                 }
 232
 233                 static public void LogToFile (string path, string name, bool foreground_mode)
 234                 {
 235                         defaultLogName = name;
 236                         if (defaultLogName.Length > 6)
 237                                 defaultLogName = defaultLogName.Substring (0, 6);
 238                         else
 239                                 defaultLogName = defaultLogName.PadRight (6);
 240
 241                         string timestamped_name = String.Format ("{0:yyyy-MM-dd-HH-mm-ss}-{1}", DateTime.Now, name);
 242                         string log_path = Path.Combine (path, timestamped_name);
 243                         string log_link = Path.Combine (path, "current-" + name);
 244
 245                         // Delete old and obsolete log files
 246                         PruneOldLogs (path, name);
 247
 248                         // Open the log file and set it as the default
 249                         // destination for log messages.
 250                         // Also redirect stdout and stderr to the same file.
 251                         FileStream log_stream = new FileStream (log_path,
 252                                                                 FileMode.Append,
 253                                                                 FileAccess.Write,
 254                                                                 FileShare.Write);
 255                         TextWriter log_writer = new StreamWriter (log_stream);
 256
 257                         File.Delete (log_link);
 258                         Mono.Posix.Syscall.symlink (log_path, log_link);
 259
 260                         Logger.DefaultWriter = log_writer;
 261                         Logger.DefaultEcho = foreground_mode;
 262
 263                         if (! foreground_mode) {
 264
 265                                 // Redirect stdout and stderr to the logfile
 266                                 Console.SetOut (Logger.DefaultWriter);
 267                                 Console.SetError (Logger.DefaultWriter);
 268
 269                                 // Redirect stdin to /dev/null
 270                                 FileStream dev_null_stream = new FileStream ("/dev/null",
 271                                                                              FileMode.Open,
 272                                                                              FileAccess.Read,
 273                                                                              FileShare.ReadWrite);
 274                                 TextReader dev_null_reader = new StreamReader (dev_null_stream);
 275                                 Console.SetIn (dev_null_reader);
 276                         }
 277                 }
 278
 279                 ////////////////////////////////////////////////////////////////////////////////
 280
 281                 static Logger ()
 282                 {
 283                         // Parse the contents of the BEAGLE_DEBUG environment variable
 284                         // and adjust the default log levels accordingly.
 285                         string debug = System.Environment.GetEnvironmentVariable ("BEAGLE_DEBUG");
 286                         if (debug != null) {
 287                                 string[] debugArgs = debug.Split (',');
 288                                 foreach (string arg in debugArgs) {
 289                                         if (arg.Trim () == "all") {
 290                                                 Logger.DefaultLevel = LogLevel.Debug;
 291                                         }
 292                                 }
 293
 294                                 foreach (string arg_raw in debugArgs) {
 295                                         string arg = arg_raw.Trim ();
 296
 297                                         if (arg.Length == 0 || arg == "all")
 298                                                 continue;
 299
 300                                         if (arg[0] == '-') {
 301                                                 string name = arg.Substring (1);
 302                                                 Logger log = Logger.Get (name);
 303                                                 log.Level = LogLevel.Info;
 304                                         } else {
 305                                                 Logger log = Logger.Get (arg);
 306                                                 log.Level = LogLevel.Debug;
 307                                         }
 308                                 }
 309                         }
 310                 }
 311         }
 312 }
 313