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 LogLevel defaultLevel = LogLevel.Debug; //LogLevel.Info;
  48                 private static TextWriter defaultWriter = null;
  49                 private static bool defaultEcho = true; //false;
  50                 private static string defaultLogName = null;
  51
  52                 public static Logger Log {
  53                         get {
  54                                 return Get ("other");
  55                         }
  56                 }
  57
  58                 public static Logger Get (string logName)
  59                 {
  60                         if (loggers.ContainsKey (logName)) {
  61                                 return (Logger)loggers[logName];
  62                         } else {
  63                                 Logger log = new Logger (logName);
  64                                 log.Level = defaultLevel;
  65                                 log.Writer = defaultWriter;
  66                                 log.Echo = defaultEcho;
  67                                 loggers[logName] = log;
  68                                 return log;
  69                         }
  70                 }
  71
  72                 public static LogLevel DefaultLevel {
  73                         get { return defaultLevel; }
  74                         set { defaultLevel = value; }
  75                 }
  76
  77
  78                 public static TextWriter DefaultWriter {
  79                         get { return defaultWriter; }
  80                         set { defaultWriter = value; }
  81                 }
  82
  83                 public static bool DefaultEcho {
  84                         get { return defaultEcho; }
  85                         set { defaultEcho = value; }
  86                 }
  87
  88                 private static object write_lock = new object ();
  89
  90                 private bool levelSet = false;
  91                 private LogLevel level;
  92                 private TextWriter writer = null;
  93                 private bool echo = false;
  94
  95                 private Logger (string name) {
  96                 }
  97
  98                 public LogLevel Level {
  99                         get { lock (this) { return (levelSet) ? level : DefaultLevel; } }
 100                         set { lock (this) { level = value; levelSet = true; } }
 101                 }
 102
 103                 public TextWriter Writer {
 104                         get { return writer; }
 105                         set { writer = value; }
 106                 }
 107
 108                 public bool Echo {
 109                         get { return echo; }
 110                         set { echo = value; }
 111                 }
 112
 113                 // Multiple logs can be merge-sorted via "sort -m log1 log2 ..."
 114                 private string GetStamp ()
 115                 {
 116                         StringBuilder builder = new StringBuilder ();
 117                         builder.AppendFormat ("{0:yy-MM-dd HH.mm.ss.ff} ", DateTime.Now);
 118                         builder.AppendFormat ("{0:00000} ", Process.GetCurrentProcess().Id);
 119                         if (defaultLogName != null) {
 120                                 builder.AppendFormat (defaultLogName);
 121                                 builder.Append (' ');
 122                         }
 123                         return builder.ToString ();
 124                 }
 125
 126                 private void WriteLine (string level, string message) {
 127                         if (Writer != null) {
 128                                 lock (write_lock) {
 129                                         Writer.WriteLine ("{0}{1}: {2}", GetStamp (), level, message);
 130                                         Writer.Flush ();
 131                                 }
 132                         }
 133                         if (Echo)
 134                                 System.Console.WriteLine ("{0}: {1}", level, message);
 135                 }
 136
 137                 public void Debug (string message, params object [] args)
 138                 {
 139                         if (IsDebugEnabled) {
 140                                 WriteLine ("DEBUG", String.Format (message, args));
 141                         }
 142                 }
 143
 144                 public void Debug (Exception e)
 145                 {
 146                         Debug ("{0}", e);
 147                 }
 148
 149                 public void Info (string message, params object [] args)
 150                 {
 151                         if (IsInfoEnabled) {
 152                                 WriteLine ("INFO", String.Format (message, args));
 153                         }
 154                 }
 155
 156                 public void Info (Exception e)
 157                 {
 158                         Info ("{0}", e);
 159                 }
 160
 161                 public void Warn (string message, params object [] args)
 162                 {
 163                         if (IsWarnEnabled) {
 164                                 WriteLine ("WARN", String.Format (message, args));
 165                         }
 166                 }
 167
 168                 public void Warn (Exception e)
 169                 {
 170                         Warn ("{0}", e);
 171                 }
 172
 173                 public void Error (string message, params object [] args)
 174                 {
 175                         if (IsErrorEnabled) {
 176                                 WriteLine ("ERROR", String.Format (message, args));
 177                         }
 178                 }
 179
 180                 public void Error (Exception e)
 181                 {
 182                         Error ("{0}", e);
 183                 }
 184
 185                 public void Fatal (string message, params object [] args)
 186                 {
 187                         if (IsFatalEnabled) {
 188                                 WriteLine ("FATAL", String.Format (message, args));
 189                         }
 190                 }
 191
 192                 public void Fatal (Exception e)
 193                 {
 194                         Fatal ("{0}", e);
 195                 }
 196
 197                 public bool IsDebugEnabled { get { return level >= LogLevel.Debug; } }
 198                 public bool IsInfoEnabled { get { return level >= LogLevel.Info; } }
 199                 public bool IsWarnEnabled { get { return level >= LogLevel.Warn; } }
 200                 public bool IsErrorEnabled { get { return level >= LogLevel.Error;} }
 201                 public bool IsFatalEnabled { get { return level >= LogLevel.Fatal; } }
 202
 203                 ////////////////////////////////////////////////////////////////////////////////
 204
 205                 static private void PruneOldLogs (string path, string instance)
 206                 {
 207                         DateTime magic_date = DateTime.Now.AddDays (-7);
 208                         DirectoryInfo dir = new DirectoryInfo (path);
 209
 210                         foreach (FileInfo file in dir.GetFiles ()) {
 211                                 if (file.Name.StartsWith ("current") || (! file.Name.EndsWith (instance)))
 212                                         continue;
 213
 214                                 int last_dash = file.Name.LastIndexOf ("-");
 215                                 if (last_dash == -1)
 216                                         continue; // skip strange-looking files
 217
 218                                 string date = file.Name.Substring (0, last_dash);
 219
 220                                 try {
 221                                         DateTime log_date;
 222                                         log_date = DateTime.ParseExact (date, "yyyy-MM-dd-HH-mm-ss", null);
 223                                         if (log_date < magic_date)
 224                                                 file.Delete ();
 225                                 } catch (Exception e) { }
 226                         }
 227                 }
 228
 229                 static public void LogToFile (string path, string name, bool foreground_mode)
 230                 {
 231                         defaultLogName = name;
 232                         if (defaultLogName.Length > 6)
 233                                 defaultLogName = defaultLogName.Substring (0, 6);
 234                         else
 235                                 defaultLogName = defaultLogName.PadRight (6);
 236
 237                         string timestamped_name = String.Format ("{0:yyyy-MM-dd-HH-mm-ss}-{1}", DateTime.Now, name);
 238                         string log_path = Path.Combine (path, timestamped_name);
 239                         string log_link = Path.Combine (path, "current-" + name);
 240
 241                         // Delete old and obsolete log files
 242                         PruneOldLogs (path, name);
 243
 244                         // Open the log file and set it as the default
 245                         // destination for log messages.
 246                         // Also redirect stdout and stderr to the same file.
 247                         FileStream log_stream = new FileStream (log_path,
 248                                                                 FileMode.Append,
 249                                                                 FileAccess.Write,
 250                                                                 FileShare.Write);
 251                         TextWriter log_writer = new StreamWriter (log_stream);
 252
 253                         File.Delete (log_link);
 254                         Mono.Posix.Syscall.symlink (log_path, log_link);
 255
 256                         Logger.DefaultWriter = log_writer;
 257                         Logger.DefaultEcho = foreground_mode;
 258
 259                         if (! foreground_mode) {
 260
 261                                 // Redirect stdout and stderr to the logfile
 262                                 Console.SetOut (Logger.DefaultWriter);
 263                                 Console.SetError (Logger.DefaultWriter);
 264
 265                                 // Redirect stdin to /dev/null
 266                                 FileStream dev_null_stream = new FileStream ("/dev/null",
 267                                                                              FileMode.Open,
 268                                                                              FileAccess.Read,
 269                                                                              FileShare.ReadWrite);
 270                                 TextReader dev_null_reader = new StreamReader (dev_null_stream);
 271                                 Console.SetIn (dev_null_reader);
 272                         }
 273                 }
 274
 275                 ////////////////////////////////////////////////////////////////////////////////
 276
 277                 static Logger ()
 278                 {
 279                         // Parse the contents of the BEAGLE_DEBUG environment variable
 280                         // and adjust the default log levels accordingly.
 281                         string debug = System.Environment.GetEnvironmentVariable ("BEAGLE_DEBUG");
 282                         if (debug != null) {
 283                                 string[] debugArgs = debug.Split (',');
 284                                 foreach (string arg in debugArgs) {
 285                                         if (arg.Trim () == "all") {
 286                                                 Logger.DefaultLevel = LogLevel.Debug;
 287                                         }
 288                                 }
 289
 290                                 foreach (string arg_raw in debugArgs) {
 291                                         string arg = arg_raw.Trim ();
 292
 293                                         if (arg.Length == 0 || arg == "all")
 294                                                 continue;
 295
 296                                         if (arg[0] == '-') {
 297                                                 string name = arg.Substring (1);
 298                                                 Logger log = Logger.Get (name);
 299                                                 log.Level = LogLevel.Info;
 300                                         } else {
 301                                                 Logger log = Logger.Get (arg);
 302                                                 log.Level = LogLevel.Debug;
 303                                         }
 304                                 }
 305                         }
 306                 }
 307         }
 308 }
 309