mcs/class/Mono.Posix/Mono.Unix/UnixStream.cs

   1 //
   2 // Mono.Unix/UnixStream.cs
   3 //
   4 // Authors:
   5 //   Jonathan Pryor (jonpryor@vt.edu)
   6 //
   7 // (C) 2004-2006 Jonathan Pryor
   8 // (C) 2007 Novell, Inc.
   9 //
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.IO;
  33 using System.Runtime.InteropServices;
  34 using System.Text;
  35 using Mono.Unix;
  36
  37 namespace Mono.Unix {
  38
  39         public sealed class UnixStream : Stream, IDisposable
  40         {
  41                 public const int InvalidFileDescriptor = -1;
  42                 public const int StandardInputFileDescriptor = 0;
  43                 public const int StandardOutputFileDescriptor = 1;
  44                 public const int StandardErrorFileDescriptor = 2;
  45
  46                 public UnixStream (int fileDescriptor)
  47                         : this (fileDescriptor, true) {}
  48
  49                 public UnixStream (int fileDescriptor, bool ownsHandle)
  50                 {
  51                         if (InvalidFileDescriptor == fileDescriptor)
  52                                 throw new ArgumentException (Locale.GetText ("Invalid file descriptor"), "fileDescriptor");
  53
  54                         this.fileDescriptor = fileDescriptor;
  55                         this.owner = ownsHandle;
  56
  57                         long offset = Native.Syscall.lseek (fileDescriptor, 0, Native.SeekFlags.SEEK_CUR);
  58                         if (offset != -1)
  59                                 canSeek = true;
  60                         long read = Native.Syscall.read (fileDescriptor, IntPtr.Zero, 0);
  61                         if (read != -1)
  62                                 canRead = true;
  63                         long write = Native.Syscall.write (fileDescriptor, IntPtr.Zero, 0);
  64                         if (write != -1)
  65                                 canWrite = true;
  66                 }
  67
  68                 private void AssertNotDisposed ()
  69                 {
  70                         if (fileDescriptor == InvalidFileDescriptor)
  71                                 throw new ObjectDisposedException ("Invalid File Descriptor");
  72                 }
  73
  74                 public int Handle {
  75                         get {return fileDescriptor;}
  76                 }
  77
  78                 public override bool CanRead {
  79                         get {return canRead;}
  80                 }
  81
  82                 public override bool CanSeek {
  83                         get {return canSeek;}
  84                 }
  85
  86                 public override bool CanWrite {
  87                         get {return canWrite;}
  88                 }
  89
  90                 public override long Length {
  91                         get {
  92                                 AssertNotDisposed ();
  93                                 if (!CanSeek)
  94                                         throw new NotSupportedException ("File descriptor doesn't support seeking");
  95                                 RefreshStat ();
  96                                 return stat.st_size;
  97                         }
  98                 }
  99
 100                 public override long Position {
 101                         get {
 102                                 AssertNotDisposed ();
 103                                 if (!CanSeek)
 104                                         throw new NotSupportedException ("The stream does not support seeking");
 105                                 long pos = Native.Syscall.lseek (fileDescriptor, 0, Native.SeekFlags.SEEK_CUR);
 106                                 if (pos == -1)
 107                                         UnixMarshal.ThrowExceptionForLastError ();
 108                                 return (long) pos;
 109                         }
 110                         set {
 111                                 Seek (value, SeekOrigin.Begin);
 112                         }
 113                 }
 114
 115                 [CLSCompliant (false)]
 116                 public Native.FilePermissions Protection {
 117                         get {
 118                                 RefreshStat ();
 119                                 return stat.st_mode;
 120                         }
 121                         set {
 122                                 // we can't change file type with fchmod, so clear out that portion
 123                                 value &= ~Native.FilePermissions.S_IFMT;
 124                                 int r = Native.Syscall.fchmod (fileDescriptor, value);
 125                                 UnixMarshal.ThrowExceptionForLastErrorIf (r);
 126                         }
 127                 }
 128
 129                 public FileTypes FileType {
 130                         get {
 131                                 int type = (int) Protection;
 132                                 return (FileTypes) (type & (int) UnixFileSystemInfo.AllFileTypes);
 133                         }
 134                         // no set as fchmod(2) won't accept changing the file type.
 135                 }
 136
 137                 public FileAccessPermissions FileAccessPermissions {
 138                         get {
 139                                 int perms = (int) Protection;
 140                                 return (FileAccessPermissions) (perms & (int) FileAccessPermissions.AllPermissions);
 141                         }
 142                         set {
 143                                 int perms = (int) Protection;
 144                                 perms &= (int) ~FileAccessPermissions.AllPermissions;
 145                                 perms |= (int) value;
 146                                 Protection = (Native.FilePermissions) perms;
 147                         }
 148                 }
 149
 150                 public FileSpecialAttributes FileSpecialAttributes {
 151                         get {
 152                                 int attrs = (int) Protection;
 153                                 return (FileSpecialAttributes) (attrs & (int) UnixFileSystemInfo.AllSpecialAttributes);
 154                         }
 155                         set {
 156                                 int perms = (int) Protection;
 157                                 perms &= (int) ~UnixFileSystemInfo.AllSpecialAttributes;
 158                                 perms |= (int) value;
 159                                 Protection = (Native.FilePermissions) perms;
 160                         }
 161                 }
 162
 163                 public UnixUserInfo OwnerUser {
 164                         get {RefreshStat (); return new UnixUserInfo (stat.st_uid);}
 165                 }
 166
 167                 public long OwnerUserId {
 168                         get {RefreshStat (); return stat.st_uid;}
 169                 }
 170
 171                 public UnixGroupInfo OwnerGroup {
 172                         get {RefreshStat (); return new UnixGroupInfo (stat.st_gid);}
 173                 }
 174
 175                 public long OwnerGroupId {
 176                         get {RefreshStat (); return stat.st_gid;}
 177                 }
 178
 179                 private void RefreshStat ()
 180                 {
 181                         AssertNotDisposed ();
 182                         int r = Native.Syscall.fstat (fileDescriptor, out stat);
 183                         UnixMarshal.ThrowExceptionForLastErrorIf (r);
 184                 }
 185
 186                 public void AdviseFileAccessPattern (FileAccessPattern pattern, long offset, long len)
 187                 {
 188                         FileHandleOperations.AdviseFileAccessPattern (fileDescriptor, pattern, offset, len);
 189                 }
 190
 191                 public void AdviseFileAccessPattern (FileAccessPattern pattern)
 192                 {
 193                         AdviseFileAccessPattern (pattern, 0, 0);
 194                 }
 195
 196                 public override void Flush ()
 197                 {
 198                 }
 199
 200                 public override unsafe int Read ([In, Out] byte[] buffer, int offset, int count)
 201                 {
 202                         AssertNotDisposed ();
 203                         AssertValidBuffer (buffer, offset, count);
 204                         if (!CanRead)
 205                                 throw new NotSupportedException ("Stream does not support reading");
 206
 207                         if (buffer.Length == 0)
 208                                 return 0;
 209
 210                         long r = 0;
 211                         fixed (byte* buf = &buffer[offset]) {
 212                                 do {
 213                                         r = Native.Syscall.read (fileDescriptor, buf, (ulong) count);
 214                                 } while (UnixMarshal.ShouldRetrySyscall ((int) r));
 215                         }
 216                         if (r == -1)
 217                                 UnixMarshal.ThrowExceptionForLastError ();
 218                         return (int) r;
 219                 }
 220
 221                 private void AssertValidBuffer (byte[] buffer, int offset, int count)
 222                 {
 223                         if (buffer == null)
 224                                 throw new ArgumentNullException ("buffer");
 225                         if (offset < 0)
 226                                 throw new ArgumentOutOfRangeException ("offset", "< 0");
 227                         if (count < 0)
 228                                 throw new ArgumentOutOfRangeException ("count", "< 0");
 229                         if (offset > buffer.Length)
 230                                 throw new ArgumentException ("destination offset is beyond array size");
 231                         if (offset > (buffer.Length - count))
 232                                 throw new ArgumentException ("would overrun buffer");
 233                 }
 234
 235                 public unsafe int ReadAtOffset ([In, Out] byte[] buffer,
 236                         int offset, int count, long fileOffset)
 237                 {
 238                         AssertNotDisposed ();
 239                         AssertValidBuffer (buffer, offset, count);
 240                         if (!CanRead)
 241                                 throw new NotSupportedException ("Stream does not support reading");
 242
 243                         if (buffer.Length == 0)
 244                                 return 0;
 245
 246                         long r = 0;
 247                         fixed (byte* buf = &buffer[offset]) {
 248                                 do {
 249                                         r = Native.Syscall.pread (fileDescriptor, buf, (ulong) count, fileOffset);
 250                                 } while (UnixMarshal.ShouldRetrySyscall ((int) r));
 251                         }
 252                         if (r == -1)
 253                                 UnixMarshal.ThrowExceptionForLastError ();
 254                         return (int) r;
 255                 }
 256
 257                 public override long Seek (long offset, SeekOrigin origin)
 258                 {
 259                         AssertNotDisposed ();
 260                         if (!CanSeek)
 261                                 throw new NotSupportedException ("The File Descriptor does not support seeking");
 262                         if (offset > int.MaxValue)
 263                                 throw new ArgumentOutOfRangeException ("offset", "too large");
 264
 265                         Native.SeekFlags sf = Native.SeekFlags.SEEK_CUR;
 266                         switch (origin) {
 267                                 case SeekOrigin.Begin:   sf = Native.SeekFlags.SEEK_SET; break;
 268                                 case SeekOrigin.Current: sf = Native.SeekFlags.SEEK_CUR; break;
 269                                 case SeekOrigin.End:     sf = Native.SeekFlags.SEEK_END; break;
 270                         }
 271
 272                         long pos = Native.Syscall.lseek (fileDescriptor, offset, sf);
 273                         if (pos == -1)
 274                                 UnixMarshal.ThrowExceptionForLastError ();
 275                         return (long) pos;
 276                 }
 277
 278                 public override void SetLength (long value)
 279                 {
 280                         AssertNotDisposed ();
 281                         if (value < 0)
 282                                 throw new ArgumentOutOfRangeException ("value", "< 0");
 283                         if (!CanSeek && !CanWrite)
 284                                 throw new NotSupportedException ("You can't truncating the current file descriptor");
 285
 286                         int r;
 287                         do {
 288                                 r = Native.Syscall.ftruncate (fileDescriptor, value);
 289                         } while (UnixMarshal.ShouldRetrySyscall (r));
 290                         UnixMarshal.ThrowExceptionForLastErrorIf (r);
 291                 }
 292
 293                 public override unsafe void Write (byte[] buffer, int offset, int count)
 294                 {
 295                         AssertNotDisposed ();
 296                         AssertValidBuffer (buffer, offset, count);
 297                         if (!CanWrite)
 298                                 throw new NotSupportedException ("File Descriptor does not support writing");
 299
 300                         if (buffer.Length == 0)
 301                                 return;
 302
 303                         long r = 0;
 304                         fixed (byte* buf = &buffer[offset]) {
 305                                 do {
 306                                         r = Native.Syscall.write (fileDescriptor, buf, (ulong) count);
 307                                 } while (UnixMarshal.ShouldRetrySyscall ((int) r));
 308                         }
 309                         if (r == -1)
 310                                 UnixMarshal.ThrowExceptionForLastError ();
 311                 }
 312
 313                 public unsafe void WriteAtOffset (byte[] buffer,
 314                         int offset, int count, long fileOffset)
 315                 {
 316                         AssertNotDisposed ();
 317                         AssertValidBuffer (buffer, offset, count);
 318                         if (!CanWrite)
 319                                 throw new NotSupportedException ("File Descriptor does not support writing");
 320
 321                         if (buffer.Length == 0)
 322                                 return;
 323
 324                         long r = 0;
 325                         fixed (byte* buf = &buffer[offset]) {
 326                                 do {
 327                                         r = Native.Syscall.pwrite (fileDescriptor, buf, (ulong) count, fileOffset);
 328                                 } while (UnixMarshal.ShouldRetrySyscall ((int) r));
 329                         }
 330                         if (r == -1)
 331                                 UnixMarshal.ThrowExceptionForLastError ();
 332                 }
 333
 334                 public void SendTo (UnixStream output)
 335                 {
 336                         SendTo (output, (ulong) output.Length);
 337                 }
 338
 339                 [CLSCompliant (false)]
 340                 public void SendTo (UnixStream output, ulong count)
 341                 {
 342                         SendTo (output.Handle, count);
 343                 }
 344
 345                 [CLSCompliant (false)]
 346                 public void SendTo (int out_fd, ulong count)
 347                 {
 348                         if (!CanWrite)
 349                                 throw new NotSupportedException ("Unable to write to the current file descriptor");
 350                         long offset = Position;
 351                         long r = Native.Syscall.sendfile (out_fd, fileDescriptor, ref offset, count);
 352                         if (r == -1)
 353                                 UnixMarshal.ThrowExceptionForLastError ();
 354                 }
 355
 356                 public void SetOwner (long user, long group)
 357                 {
 358                         AssertNotDisposed ();
 359
 360                         int r = Native.Syscall.fchown (fileDescriptor,
 361                                         Convert.ToUInt32 (user), Convert.ToUInt32 (group));
 362                         UnixMarshal.ThrowExceptionForLastErrorIf (r);
 363                 }
 364
 365                 public void SetOwner (string user, string group)
 366                 {
 367                         AssertNotDisposed ();
 368
 369                         long uid = new UnixUserInfo (user).UserId;
 370                         long gid = new UnixGroupInfo (group).GroupId;
 371                         SetOwner (uid, gid);
 372                 }
 373
 374                 public void SetOwner (string user)
 375                 {
 376                         AssertNotDisposed ();
 377
 378                         Native.Passwd pw = Native.Syscall.getpwnam (user);
 379                         if (pw == null)
 380                                 throw new ArgumentException (Locale.GetText ("invalid username"), "user");
 381                         long uid = pw.pw_uid;
 382                         long gid = pw.pw_gid;
 383                         SetOwner (uid, gid);
 384                 }
 385
 386                 [CLSCompliant (false)]
 387                 public long GetConfigurationValue (Native.PathconfName name)
 388                 {
 389                         AssertNotDisposed ();
 390                         long r = Native.Syscall.fpathconf (fileDescriptor, name);
 391                         if (r == -1 && Native.Syscall.GetLastError() != (Native.Errno) 0)
 392                                 UnixMarshal.ThrowExceptionForLastError ();
 393                         return r;
 394                 }
 395
 396                 ~UnixStream ()
 397                 {
 398                         Close ();
 399                 }
 400
 401                 public override void Close ()
 402                 {
 403                         if (fileDescriptor == InvalidFileDescriptor)
 404                                 return;
 405
 406                         Flush ();
 407
 408                         if (!owner)
 409                                 return;
 410
 411                         int r;
 412                         do {
 413                                 r = Native.Syscall.close (fileDescriptor);
 414                         } while (UnixMarshal.ShouldRetrySyscall (r));
 415                         UnixMarshal.ThrowExceptionForLastErrorIf (r);
 416                         fileDescriptor = InvalidFileDescriptor;
 417                         GC.SuppressFinalize (this);
 418                 }
 419
 420                 void IDisposable.Dispose ()
 421                 {
 422                         AssertNotDisposed ();
 423                         if (owner) {
 424                                 Close ();
 425                         }
 426                         GC.SuppressFinalize (this);
 427                 }
 428
 429                 private bool canSeek = false;
 430                 private bool canRead = false;
 431                 private bool canWrite = false;
 432                 private bool owner = true;
 433                 private int fileDescriptor = InvalidFileDescriptor;
 434                 private Native.Stat stat;
 435         }
 436 }
 437
 438 // vim: noexpandtab