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