mcs/class/corlib/System/Environment.cs

   1 //------------------------------------------------------------------------------
   2 //
   3 // System.Environment.cs
   4 //
   5 // Copyright (C) 2001 Moonlight Enterprises, All Rights Reserved
   6 //
   7 // Author:         Jim Richardson, develop@wtfo-guru.com
   8 //                 Dan Lewis (dihlewis@yahoo.co.uk)
   9 // Created:        Saturday, August 11, 2001
  10 //
  11 //------------------------------------------------------------------------------
  12 //
  13 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  14 //
  15 // Permission is hereby granted, free of charge, to any person obtaining
  16 // a copy of this software and associated documentation files (the
  17 // "Software"), to deal in the Software without restriction, including
  18 // without limitation the rights to use, copy, modify, merge, publish,
  19 // distribute, sublicense, and/or sell copies of the Software, and to
  20 // permit persons to whom the Software is furnished to do so, subject to
  21 // the following conditions:
  22 //
  23 // The above copyright notice and this permission notice shall be
  24 // included in all copies or substantial portions of the Software.
  25 //
  26 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  27 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  28 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  29 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  30 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  31 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  32 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  33 //
  34
  35 using System.IO;
  36 using System.Collections;
  37 using System.Runtime.CompilerServices;
  38 using System.Security;
  39 using System.Security.Permissions;
  40 using System.Text;
  41 using System.Runtime.InteropServices;
  42
  43 namespace System {
  44
  45         [ComVisible (true)]
  46         public static class Environment {
  47
  48                 /*
  49                  * This is the version number of the corlib-runtime interface. When
  50                  * making changes to this interface (by changing the layout
  51                  * of classes the runtime knows about, changing icall signature or
  52                  * semantics etc), increment this variable. Also increment the
  53                  * pair of this variable in the runtime in metadata/appdomain.c.
  54                  * Changes which are already detected at runtime, like the addition
  55                  * of icalls, do not require an increment.
  56                  */
  57 #pragma warning disable 169
  58                 private const int mono_corlib_version = 94;
  59 #pragma warning restore 169
  60
  61                 [ComVisible (true)]
  62                 public enum SpecialFolder
  63                 {
  64                         MyDocuments = 0x05,
  65                         Desktop = 0x00,
  66                         MyComputer = 0x11,
  67                         Programs = 0x02,
  68                         Personal = 0x05,
  69                         Favorites = 0x06,
  70                         Startup = 0x07,
  71                         Recent = 0x08,
  72                         SendTo = 0x09,
  73                         StartMenu = 0x0b,
  74                         MyMusic = 0x0d,
  75                         DesktopDirectory = 0x10,
  76                         Templates = 0x15,
  77                         ApplicationData = 0x1a,
  78                         LocalApplicationData = 0x1c,
  79                         InternetCache = 0x20,
  80                         Cookies = 0x21,
  81                         History = 0x22,
  82                         CommonApplicationData   = 0x23,
  83                         System = 0x25,
  84                         ProgramFiles = 0x26,
  85                         MyPictures = 0x27,
  86                         CommonProgramFiles = 0x2b,
  87 #if NET_4_0 || MOONLIGHT
  88                         MyVideos = 0x0e,
  89 #endif
  90 #if NET_4_0
  91                         NetworkShortcuts = 0x13,
  92                         Fonts = 0x14,
  93                         CommonStartMenu = 0x16,
  94                         CommonPrograms = 0x17,
  95                         CommonStartup = 0x18,
  96                         CommonDesktopDirectory = 0x19,
  97                         PrinterShortcuts = 0x1b,
  98                         Windows = 0x24,
  99                         UserProfile = 0x28,
 100                         SystemX86 = 0x29,
 101                         ProgramFilesX86 = 0x2a,
 102                         CommonProgramFilesX86 = 0x2c,
 103                         CommonTemplates = 0x2d,
 104                         CommonDocuments = 0x2e,
 105                         CommonAdminTools = 0x2f,
 106                         AdminTools = 0x30,
 107                         CommonMusic = 0x35,
 108                         CommonPictures = 0x36,
 109                         CommonVideos = 0x37,
 110                         Resources = 0x38,
 111                         LocalizedResources = 0x39,
 112                         CommonOemLinks = 0x3a,
 113                         CDBurning = 0x3b,
 114 #endif
 115                 }
 116
 117 #if NET_4_0
 118                 public
 119 #else
 120                 internal
 121 #endif
 122                 enum SpecialFolderOption {
 123                         None = 0,
 124                         DoNotVerify = 0x4000,
 125                         Create = 0x8000
 126                 }
 127
 128                 /// <summary>
 129                 /// Gets the command line for this process
 130                 /// </summary>
 131                 public static string CommandLine {
 132                         // note: security demand inherited from calling GetCommandLineArgs
 133                         get {
 134                                 StringBuilder sb = new StringBuilder ();
 135                                 foreach (string str in GetCommandLineArgs ()) {
 136                                         bool escape = false;
 137                                         string quote = "";
 138                                         string s = str;
 139                                         for (int i = 0; i < s.Length; i++) {
 140                                                 if (quote.Length == 0 && Char.IsWhiteSpace (s [i])) {
 141                                                         quote = "\"";
 142                                                 } else if (s [i] == '"') {
 143                                                         escape = true;
 144                                                 }
 145                                         }
 146                                         if (escape && quote.Length != 0) {
 147                                                 s = s.Replace ("\"", "\\\"");
 148                                         }
 149                                         sb.AppendFormat ("{0}{1}{0} ", quote, s);
 150                                 }
 151                                 if (sb.Length > 0)
 152                                         sb.Length--;
 153                                 return sb.ToString ();
 154                         }
 155                 }
 156
 157                 /// <summary>
 158                 /// Gets or sets the current directory. Actually this is supposed to get
 159                 /// and/or set the process start directory acording to the documentation
 160                 /// but actually test revealed at beta2 it is just Getting/Setting the CurrentDirectory
 161                 /// </summary>
 162                 public static string CurrentDirectory
 163                 {
 164                         get {
 165                                 return Directory.GetCurrentDirectory ();
 166                         }
 167                         set {
 168                                 Directory.SetCurrentDirectory (value);
 169                         }
 170                 }
 171
 172                 /// <summary>
 173                 /// Gets or sets the exit code of this process
 174                 /// </summary>
 175                 public extern static int ExitCode
 176                 {
 177                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 178                         get;
 179                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 180                         set;
 181                 }
 182
 183                 static public extern bool HasShutdownStarted
 184                 {
 185                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 186                         get;
 187                 }
 188
 189
 190                 /// <summary>
 191                 /// Gets the name of the local computer
 192                 /// </summary>
 193                 public extern static string MachineName {
 194                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 195                         [EnvironmentPermission (SecurityAction.Demand, Read="COMPUTERNAME")]
 196                         [SecurityPermission (SecurityAction.Demand, UnmanagedCode=true)]
 197                         get;
 198                 }
 199
 200                 /// <summary>
 201                 /// Gets the standard new line value
 202                 /// </summary>
 203                 public extern static string NewLine {
 204                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 205                         get;
 206                 }
 207
 208                 //
 209                 // Support methods and fields for OSVersion property
 210                 //
 211                 static OperatingSystem os;
 212
 213                 static extern PlatformID Platform {
 214                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 215                         get;
 216                 }
 217
 218                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 219                 internal static extern string GetOSVersionString ();
 220
 221                 /// <summary>
 222                 /// Gets the current OS version information
 223                 /// </summary>
 224                 public static OperatingSystem OSVersion {
 225                         get {
 226                                 if (os == null) {
 227                                         Version v = Version.CreateFromString (GetOSVersionString ());
 228                                         PlatformID p = Platform;
 229                                         if (p == PlatformID.MacOSX)
 230                                                 p = PlatformID.Unix;
 231                                         os = new OperatingSystem (p, v);
 232                                 }
 233                                 return os;
 234                         }
 235                 }
 236
 237                 /// <summary>
 238                 /// Get StackTrace
 239                 /// </summary>
 240                 public static string StackTrace {
 241                         [EnvironmentPermission (SecurityAction.Demand, Unrestricted=true)]
 242                         get {
 243                                 System.Diagnostics.StackTrace trace = new System.Diagnostics.StackTrace (0, true);
 244                                 return trace.ToString ();
 245                         }
 246                 }
 247 #if !NET_2_1
 248                 /// <summary>
 249                 /// Get a fully qualified path to the system directory
 250                 /// </summary>
 251                 public static string SystemDirectory {
 252                         get {
 253                                 return GetFolderPath (SpecialFolder.System);
 254                         }
 255                 }
 256 #endif
 257                 /// <summary>
 258                 /// Get the number of milliseconds that have elapsed since the system was booted
 259                 /// </summary>
 260                 public extern static int TickCount {
 261                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 262                         get;
 263                 }
 264
 265                 /// <summary>
 266                 /// Get UserDomainName
 267                 /// </summary>
 268                 public static string UserDomainName {
 269                         // FIXME: this variable doesn't exist (at least not on WinXP) - reported to MS as FDBK20562
 270                         [EnvironmentPermission (SecurityAction.Demand, Read="USERDOMAINNAME")]
 271                         get {
 272                                 return MachineName;
 273                         }
 274                 }
 275
 276                 /// <summary>
 277                 /// Gets a flag indicating whether the process is in interactive mode
 278                 /// </summary>
 279                 [MonoTODO ("Currently always returns false, regardless of interactive state")]
 280                 public static bool UserInteractive {
 281                         get {
 282                                 return false;
 283                         }
 284                 }
 285
 286                 /// <summary>
 287                 /// Get the user name of current process is running under
 288                 /// </summary>
 289                 public extern static string UserName {
 290                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 291                         [EnvironmentPermission (SecurityAction.Demand, Read="USERNAME;USER")]
 292                         get;
 293                 }
 294
 295                 /// <summary>
 296                 /// Get the version of the common language runtime
 297                 /// </summary>
 298                 public static Version Version {
 299                         get {
 300                                 return new Version (Consts.FxFileVersion);
 301                         }
 302                 }
 303
 304                 /// <summary>
 305                 /// Get the amount of physical memory mapped to process
 306                 /// </summary>
 307                 [MonoTODO ("Currently always returns zero")]
 308                 public static long WorkingSet {
 309                         [EnvironmentPermission (SecurityAction.Demand, Unrestricted=true)]
 310                         get { return 0; }
 311                 }
 312
 313                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 314                 [SecurityPermission (SecurityAction.Demand, UnmanagedCode=true)]
 315                 public extern static void Exit (int exitCode);
 316
 317                 /// <summary>
 318                 /// Substitute environment variables in the argument "name"
 319                 /// </summary>
 320                 public static string ExpandEnvironmentVariables (string name)
 321                 {
 322                         if (name == null)
 323                                 throw new ArgumentNullException ("name");
 324
 325                         int off1 = name.IndexOf ('%');
 326                         if (off1 == -1)
 327                                 return name;
 328
 329                         int len = name.Length;
 330                         int off2 = 0;
 331                         if (off1 == len - 1 || (off2 = name.IndexOf ('%', off1 + 1)) == -1)
 332                                 return name;
 333
 334                         StringBuilder result = new StringBuilder ();
 335                         result.Append (name, 0, off1);
 336                         Hashtable tbl = null;
 337                         do {
 338                                 string var = name.Substring (off1 + 1, off2 - off1 - 1);
 339                                 string value = GetEnvironmentVariable (var);
 340                                 if (value == null && Environment.IsRunningOnWindows) {
 341                                         // On windows, env. vars. are case insensitive
 342                                         if (tbl == null)
 343                                                 tbl = GetEnvironmentVariablesNoCase ();
 344
 345                                         value = tbl [var] as string;
 346                                 }
 347
 348                                 // If value not found, add %FOO to stream,
 349                                 //  and use the closing % for the next iteration.
 350                                 // If value found, expand it in place of %FOO%
 351                                 if (value == null) {
 352                                         result.Append ('%');
 353                                         result.Append (var);
 354                                         off2--;
 355                                 } else {
 356                                         result.Append (value);
 357                                 }
 358                                 int oldOff2 = off2;
 359                                 off1 = name.IndexOf ('%', off2 + 1);
 360                                 // If no % found for off1, don't look for one for off2
 361                                 off2 = (off1 == -1 || off2 > len-1)? -1 :name.IndexOf ('%', off1 + 1);
 362                                 // textLen is the length of text between the closing % of current iteration
 363                                 //  and the starting % of the next iteration if any. This text is added to output
 364                                 int textLen;
 365                                 // If no new % found, use all the remaining text
 366                                 if (off1 == -1 || off2 == -1)
 367                                         textLen = len - oldOff2 - 1;
 368                                 // If value found in current iteration, use text after current closing % and next %
 369                                 else if(value != null)
 370                                         textLen = off1 - oldOff2 - 1;
 371                                 // If value not found in current iteration, but a % was found for next iteration,
 372                                 //  use text from current closing % to the next %.
 373                                 else
 374                                         textLen = off1 - oldOff2;
 375                                 if(off1 >= oldOff2 || off1 == -1)
 376                                         result.Append (name, oldOff2+1, textLen);
 377                         } while (off2 > -1 && off2 < len);
 378
 379                         return result.ToString ();
 380
 381                 }
 382
 383                 /// <summary>
 384                 /// Return an array of the command line arguments of the current process
 385                 /// </summary>
 386                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 387                 [EnvironmentPermissionAttribute (SecurityAction.Demand, Read = "PATH")]
 388                 public extern static string[] GetCommandLineArgs ();
 389
 390                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 391                 internal extern static string internalGetEnvironmentVariable (string variable);
 392
 393                 /// <summary>
 394                 /// Return a string containing the value of the environment
 395                 /// variable identifed by parameter "variable"
 396                 /// </summary>
 397                 public static string GetEnvironmentVariable (string variable)
 398                 {
 399 #if !NET_2_1
 400                         if (SecurityManager.SecurityEnabled) {
 401                                 new EnvironmentPermission (EnvironmentPermissionAccess.Read, variable).Demand ();
 402                         }
 403 #endif
 404                         return internalGetEnvironmentVariable (variable);
 405                 }
 406
 407                 static Hashtable GetEnvironmentVariablesNoCase ()
 408                 {
 409                         Hashtable vars = new Hashtable (CaseInsensitiveHashCodeProvider.Default,
 410                                                         CaseInsensitiveComparer.Default);
 411
 412                         foreach (string name in GetEnvironmentVariableNames ()) {
 413                                 vars [name] = internalGetEnvironmentVariable (name);
 414                         }
 415
 416                         return vars;
 417                 }
 418
 419                 /// <summary>
 420                 /// Return a set of all environment variables and their values
 421                 /// </summary>
 422 #if !NET_2_1
 423                 public static IDictionary GetEnvironmentVariables ()
 424                 {
 425                         StringBuilder sb = null;
 426                         if (SecurityManager.SecurityEnabled) {
 427                                 // we must have access to each variable to get the lot
 428                                 sb = new StringBuilder ();
 429                                 // but (performance-wise) we do not want a stack-walk
 430                                 // for each of them so we concatenate them
 431                         }
 432
 433                         Hashtable vars = new Hashtable ();
 434                         foreach (string name in GetEnvironmentVariableNames ()) {
 435                                 vars [name] = internalGetEnvironmentVariable (name);
 436                                 if (sb != null) {
 437                                         sb.Append (name);
 438                                         sb.Append (";");
 439                                 }
 440                         }
 441
 442                         if (sb != null) {
 443                                 new EnvironmentPermission (EnvironmentPermissionAccess.Read, sb.ToString ()).Demand ();
 444                         }
 445                         return vars;
 446                 }
 447 #else
 448                 [EnvironmentPermission (SecurityAction.Demand, Unrestricted=true)]
 449                 public static IDictionary GetEnvironmentVariables ()
 450                 {
 451                         Hashtable vars = new Hashtable ();
 452                         foreach (string name in GetEnvironmentVariableNames ()) {
 453                                 vars [name] = internalGetEnvironmentVariable (name);
 454                         }
 455                         return vars;
 456                 }
 457 #endif
 458
 459                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 460                 private extern static string GetWindowsFolderPath (int folder);
 461
 462                 /// <summary>
 463                 /// Returns the fully qualified path of the
 464                 /// folder specified by the "folder" parameter
 465                 /// </summary>
 466                 public static string GetFolderPath (SpecialFolder folder)
 467                 {
 468                         return GetFolderPath (folder, SpecialFolderOption.None);
 469                 }
 470 #if NET_4_0
 471                 public
 472 #endif
 473                 static string GetFolderPath(SpecialFolder folder, SpecialFolderOption option)
 474                 {
 475                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
 476
 477                         string dir = null;
 478
 479                         if (Environment.IsRunningOnWindows)
 480                                 dir = GetWindowsFolderPath ((int) folder);
 481                         else
 482                                 dir = UnixGetFolderPath (folder, option);
 483
 484 #if !NET_2_1
 485                         if ((dir != null) && (dir.Length > 0) && SecurityManager.SecurityEnabled) {
 486                                 new FileIOPermission (FileIOPermissionAccess.PathDiscovery, dir).Demand ();
 487                         }
 488 #endif
 489                         return dir;
 490                 }
 491
 492                 private static string ReadXdgUserDir (string config_dir, string home_dir, string key, string fallback)
 493                 {
 494                         string env_path = internalGetEnvironmentVariable (key);
 495                         if (env_path != null && env_path != String.Empty) {
 496                                 return env_path;
 497                         }
 498
 499                         string user_dirs_path = Path.Combine (config_dir, "user-dirs.dirs");
 500
 501                         if (!File.Exists (user_dirs_path)) {
 502                                 return Path.Combine (home_dir, fallback);
 503                         }
 504
 505                         try {
 506                                 using(StreamReader reader = new StreamReader (user_dirs_path)) {
 507                                         string line;
 508                                         while ((line = reader.ReadLine ()) != null) {
 509                                                 line = line.Trim ();
 510                                                 int delim_index = line.IndexOf ('=');
 511                                                 if(delim_index > 8 && line.Substring (0, delim_index) == key) {
 512                                                         string path = line.Substring (delim_index + 1).Trim ('"');
 513                                                         bool relative = false;
 514
 515                                                         if (path.StartsWith ("$HOME/")) {
 516                                                                 relative = true;
 517                                                                 path = path.Substring (6);
 518                                                         } else if (!path.StartsWith ("/")) {
 519                                                                 relative = true;
 520                                                         }
 521
 522                                                         return relative ? Path.Combine (home_dir, path) : path;
 523                                                 }
 524                                         }
 525                                 }
 526                         } catch (FileNotFoundException) {
 527                         }
 528
 529                         return Path.Combine (home_dir, fallback);
 530                 }
 531
 532
 533                 // the security runtime (and maybe other parts of corlib) needs the
 534                 // information to initialize themselves before permissions can be checked
 535                 internal static string UnixGetFolderPath (SpecialFolder folder, SpecialFolderOption option)
 536                 {
 537                         string home = internalGetHome ();
 538
 539                         // http://freedesktop.org/Standards/basedir-spec/basedir-spec-0.6.html
 540
 541                         // note: skip security check for environment variables
 542                         string data = internalGetEnvironmentVariable ("XDG_DATA_HOME");
 543                         if ((data == null) || (data == String.Empty)) {
 544                                 data = Path.Combine (home, ".local");
 545                                 data = Path.Combine (data, "share");
 546                         }
 547
 548                         // note: skip security check for environment variables
 549                         string config = internalGetEnvironmentVariable ("XDG_CONFIG_HOME");
 550                         if ((config == null) || (config == String.Empty)) {
 551                                 config = Path.Combine (home, ".config");
 552                         }
 553
 554                         switch (folder) {
 555                         // MyComputer is a virtual directory
 556                         case SpecialFolder.MyComputer:
 557                                 return String.Empty;
 558
 559                         // personal == ~
 560                         case SpecialFolder.Personal:
 561 #if MONOTOUCH
 562                                 return Path.Combine (home, "Documents");
 563 #else
 564                                 return home;
 565 #endif
 566                         // use FDO's CONFIG_HOME. This data will be synced across a network like the windows counterpart.
 567                         case SpecialFolder.ApplicationData:
 568 #if MONOTOUCH
 569                         {
 570                                 string dir = Path.Combine (Path.Combine (home, "Documents"), ".config");
 571                                 if (option == SpecialFolderOption.Create){
 572                                         if (!Directory.Exists (dir))
 573                                                 Directory.CreateDirectory (dir);
 574                                 }
 575                                 return dir;
 576                         }
 577 #else
 578                                 return config;
 579 #endif
 580                         //use FDO's DATA_HOME. This is *NOT* synced
 581                         case SpecialFolder.LocalApplicationData:
 582 #if MONOTOUCH
 583                         {
 584                                 string dir = Path.Combine (home, "Documents");
 585                                 if (!Directory.Exists (dir))
 586                                         Directory.CreateDirectory (dir);
 587
 588                                 return dir;
 589                         }
 590 #else
 591                                 return data;
 592 #endif
 593
 594                         case SpecialFolder.Desktop:
 595                         case SpecialFolder.DesktopDirectory:
 596                                 return ReadXdgUserDir (config, home, "XDG_DESKTOP_DIR", "Desktop");
 597
 598                         case SpecialFolder.MyMusic:
 599                                 if (Platform == PlatformID.MacOSX)
 600                                         return Path.Combine (home, "Music");
 601                                 else
 602                                         return ReadXdgUserDir (config, home, "XDG_MUSIC_DIR", "Music");
 603
 604                         case SpecialFolder.MyPictures:
 605                                 if (Platform == PlatformID.MacOSX)
 606                                         return Path.Combine (home, "Pictures");
 607                                 else
 608                                         return ReadXdgUserDir (config, home, "XDG_PICTURES_DIR", "Pictures");
 609
 610                         case SpecialFolder.Templates:
 611                                 return ReadXdgUserDir (config, home, "XDG_TEMPLATES_DIR", "Templates");
 612 #if NET_4_0 || MOONLIGHT
 613                         case SpecialFolder.MyVideos:
 614                                 return ReadXdgUserDir (config, home, "XDG_VIDEOS_DIR", "Videos");
 615 #endif
 616 #if NET_4_0
 617                         case SpecialFolder.CommonTemplates:
 618                                 return "/usr/share/templates";
 619                         case SpecialFolder.Fonts:
 620                                 if (Platform == PlatformID.MacOSX)
 621                                         return Path.Combine (home, "Library", "Fonts");
 622
 623                                 return Path.Combine (home, ".fonts");
 624 #endif
 625                         // these simply dont exist on Linux
 626                         // The spec says if a folder doesnt exist, we
 627                         // should return ""
 628                         case SpecialFolder.Favorites:
 629                                 if (Platform == PlatformID.MacOSX)
 630                                         return Path.Combine (home, "Library", "Favorites");
 631                                 else
 632                                         return String.Empty;
 633
 634                         case SpecialFolder.ProgramFiles:
 635                                 if (Platform == PlatformID.MacOSX)
 636                                         return "/Applications";
 637                                 else
 638                                         return String.Empty;
 639
 640                         case SpecialFolder.InternetCache:
 641                                 if (Platform == PlatformID.MacOSX)
 642                                         return Path.Combine (home, "Library", "Caches");
 643                                 else
 644                                         return String.Empty;
 645
 646                         case SpecialFolder.Programs:
 647                         case SpecialFolder.SendTo:
 648                         case SpecialFolder.StartMenu:
 649                         case SpecialFolder.Startup:
 650                         case SpecialFolder.Cookies:
 651                         case SpecialFolder.History:
 652                         case SpecialFolder.Recent:
 653                         case SpecialFolder.CommonProgramFiles:
 654                         case SpecialFolder.System:
 655 #if NET_4_0
 656                         case SpecialFolder.NetworkShortcuts:
 657                         case SpecialFolder.CommonStartMenu:
 658                         case SpecialFolder.CommonPrograms:
 659                         case SpecialFolder.CommonStartup:
 660                         case SpecialFolder.CommonDesktopDirectory:
 661                         case SpecialFolder.PrinterShortcuts:
 662                         case SpecialFolder.Windows:
 663                         case SpecialFolder.UserProfile:
 664                         case SpecialFolder.SystemX86:
 665                         case SpecialFolder.ProgramFilesX86:
 666                         case SpecialFolder.CommonProgramFilesX86:
 667                         case SpecialFolder.CommonDocuments:
 668                         case SpecialFolder.CommonAdminTools:
 669                         case SpecialFolder.AdminTools:
 670                         case SpecialFolder.CommonMusic:
 671                         case SpecialFolder.CommonPictures:
 672                         case SpecialFolder.CommonVideos:
 673                         case SpecialFolder.Resources:
 674                         case SpecialFolder.LocalizedResources:
 675                         case SpecialFolder.CommonOemLinks:
 676                         case SpecialFolder.CDBurning:
 677 #endif
 678                                 return String.Empty;
 679                         // This is where data common to all users goes
 680                         case SpecialFolder.CommonApplicationData:
 681                                 return "/usr/share";
 682                         default:
 683                                 throw new ArgumentException ("Invalid SpecialFolder");
 684                         }
 685                 }
 686
 687
 688                 [EnvironmentPermission (SecurityAction.Demand, Unrestricted=true)]
 689                 public static string[] GetLogicalDrives ()
 690                 {
 691                         return GetLogicalDrivesInternal ();
 692                 }
 693
 694 #if !NET_2_1
 695                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 696                 private static extern void internalBroadcastSettingChange ();
 697
 698                 public static string GetEnvironmentVariable (string variable, EnvironmentVariableTarget target)
 699                 {
 700                         switch (target) {
 701                         case EnvironmentVariableTarget.Process:
 702                                 return GetEnvironmentVariable (variable);
 703                         case EnvironmentVariableTarget.Machine:
 704                                 new EnvironmentPermission (PermissionState.Unrestricted).Demand ();
 705                                 if (!IsRunningOnWindows)
 706                                         return null;
 707                                 using (Microsoft.Win32.RegistryKey env = Microsoft.Win32.Registry.LocalMachine.OpenSubKey (@"SYSTEM\CurrentControlSet\Control\Session Manager\Environment")) {
 708                                         object regvalue = env.GetValue (variable);
 709                                         return (regvalue == null) ? null : regvalue.ToString ();
 710                                 }
 711                         case EnvironmentVariableTarget.User:
 712                                 new EnvironmentPermission (PermissionState.Unrestricted).Demand ();
 713                                 if (!IsRunningOnWindows)
 714                                         return null;
 715                                 using (Microsoft.Win32.RegistryKey env = Microsoft.Win32.Registry.CurrentUser.OpenSubKey ("Environment", false)) {
 716                                         object regvalue = env.GetValue (variable);
 717                                         return (regvalue == null) ? null : regvalue.ToString ();
 718                                 }
 719                         default:
 720                                 throw new ArgumentException ("target");
 721                         }
 722                 }
 723
 724                 public static IDictionary GetEnvironmentVariables (EnvironmentVariableTarget target)
 725                 {
 726                         IDictionary variables = (IDictionary)new Hashtable ();
 727                         switch (target) {
 728                         case EnvironmentVariableTarget.Process:
 729                                 variables = GetEnvironmentVariables ();
 730                                 break;
 731                         case EnvironmentVariableTarget.Machine:
 732                                 new EnvironmentPermission (PermissionState.Unrestricted).Demand ();
 733                                 if (IsRunningOnWindows) {
 734                                         using (Microsoft.Win32.RegistryKey env = Microsoft.Win32.Registry.LocalMachine.OpenSubKey (@"SYSTEM\CurrentControlSet\Control\Session Manager\Environment")) {
 735                                                 string[] value_names = env.GetValueNames ();
 736                                                 foreach (string value_name in value_names)
 737                                                         variables.Add (value_name, env.GetValue (value_name));
 738                                         }
 739                                 }
 740                                 break;
 741                         case EnvironmentVariableTarget.User:
 742                                 new EnvironmentPermission (PermissionState.Unrestricted).Demand ();
 743                                 if (IsRunningOnWindows) {
 744                                         using (Microsoft.Win32.RegistryKey env = Microsoft.Win32.Registry.CurrentUser.OpenSubKey ("Environment")) {
 745                                                 string[] value_names = env.GetValueNames ();
 746                                                 foreach (string value_name in value_names)
 747                                                         variables.Add (value_name, env.GetValue (value_name));
 748                                         }
 749                                 }
 750                                 break;
 751                         default:
 752                                 throw new ArgumentException ("target");
 753                         }
 754                         return variables;
 755                 }
 756
 757                 [EnvironmentPermission (SecurityAction.Demand, Unrestricted=true)]
 758                 public static void SetEnvironmentVariable (string variable, string value)
 759                 {
 760                         SetEnvironmentVariable (variable, value, EnvironmentVariableTarget.Process);
 761                 }
 762
 763                 [EnvironmentPermission (SecurityAction.Demand, Unrestricted = true)]
 764                 public static void SetEnvironmentVariable (string variable, string value, EnvironmentVariableTarget target)
 765                 {
 766                         if (variable == null)
 767                                 throw new ArgumentNullException ("variable");
 768                         if (variable == String.Empty)
 769                                 throw new ArgumentException ("String cannot be of zero length.", "variable");
 770                         if (variable.IndexOf ('=') != -1)
 771                                 throw new ArgumentException ("Environment variable name cannot contain an equal character.", "variable");
 772                         if (variable[0] == '\0')
 773                                 throw new ArgumentException ("The first char in the string is the null character.", "variable");
 774
 775                         switch (target) {
 776                         case EnvironmentVariableTarget.Process:
 777                                 InternalSetEnvironmentVariable (variable, value);
 778                                 break;
 779                         case EnvironmentVariableTarget.Machine:
 780                                 if (!IsRunningOnWindows)
 781                                         return;
 782                                 using (Microsoft.Win32.RegistryKey env = Microsoft.Win32.Registry.LocalMachine.OpenSubKey (@"SYSTEM\CurrentControlSet\Control\Session Manager\Environment", true)) {
 783                                         if (String.IsNullOrEmpty (value))
 784                                                 env.DeleteValue (variable, false);
 785                                         else
 786                                                 env.SetValue (variable, value);
 787                                         internalBroadcastSettingChange ();
 788                                 }
 789                                 break;
 790                         case EnvironmentVariableTarget.User:
 791                                 if (!IsRunningOnWindows)
 792                                         return;
 793                                 using (Microsoft.Win32.RegistryKey env = Microsoft.Win32.Registry.CurrentUser.OpenSubKey ("Environment", true)) {
 794                                         if (String.IsNullOrEmpty (value))
 795                                                 env.DeleteValue (variable, false);
 796                                         else
 797                                                 env.SetValue (variable, value);
 798                                         internalBroadcastSettingChange ();
 799                                 }
 800                                 break;
 801                         default:
 802                                 throw new ArgumentException ("target");
 803                         }
 804                 }
 805
 806                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 807                 internal static extern void InternalSetEnvironmentVariable (string variable, string value);
 808 #endif
 809                 [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode=true)]
 810                 public static void FailFast (string message)
 811                 {
 812                         throw new NotImplementedException ();
 813                 }
 814
 815 #if NET_4_0 || MOONLIGHT
 816                 [SecurityCritical]
 817                 public static void FailFast (string message, Exception exception)
 818                 {
 819                         throw new NotImplementedException ();
 820                 }
 821 #endif
 822
 823 #if NET_4_0
 824                 public static bool Is64BitOperatingSystem {
 825                         get { return IntPtr.Size == 8; } // FIXME: is this good enough?
 826                 }
 827
 828                 public static bool Is64BitProcess {
 829                         get { return Is64BitOperatingSystem; }
 830                 }
 831
 832                 public static int SystemPageSize {
 833                         get { return GetPageSize (); }
 834                 }
 835 #endif
 836
 837                 public static extern int ProcessorCount {
 838                         [EnvironmentPermission (SecurityAction.Demand, Read="NUMBER_OF_PROCESSORS")]
 839                         [MethodImplAttribute (MethodImplOptions.InternalCall)]
 840                         get;
 841                 }
 842
 843                 // private methods
 844
 845                 internal static bool IsRunningOnWindows {
 846                         get { return ((int) Platform < 4); }
 847                 }
 848 #if !NET_2_1
 849                 //
 850                 // Used by gacutil.exe
 851                 //
 852 #pragma warning disable 169
 853                 private static string GacPath {
 854                         get {
 855                                 if (Environment.IsRunningOnWindows) {
 856                                         /* On windows, we don't know the path where mscorlib.dll will be installed */
 857                                         string corlibDir = new DirectoryInfo (Path.GetDirectoryName (typeof (int).Assembly.Location)).Parent.Parent.FullName;
 858                                         return Path.Combine (Path.Combine (corlibDir, "mono"), "gac");
 859                                 }
 860
 861                                 return Path.Combine (Path.Combine (internalGetGacPath (), "mono"), "gac");
 862                         }
 863                 }
 864 #pragma warning restore 169
 865                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 866                 internal extern static string internalGetGacPath ();
 867 #endif
 868                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 869                 private extern static string [] GetLogicalDrivesInternal ();
 870
 871                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 872                 private extern static string [] GetEnvironmentVariableNames ();
 873
 874                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 875                 internal extern static string GetMachineConfigPath ();
 876
 877                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 878                 internal extern static string internalGetHome ();
 879
 880                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 881                 internal extern static int GetPageSize ();
 882
 883                 static internal bool IsUnix {
 884                         get {
 885                                 int platform = (int) Environment.Platform;
 886
 887                                 return (platform == 4 || platform == 128 || platform == 6);
 888                         }
 889                 }
 890         }
 891 }
 892