mcs/class/WindowsBase/ZipSharp/ZipStream.cs

   1 // ZipStream.cs created with MonoDevelop
   2 // User: alan at 15:16 20/10/2008
   3 //
   4 // To change standard headers go to Edit->Preferences->Coding->Standard Headers
   5 //
   6
   7 using System;
   8 using System.IO;
   9 using System.Runtime.InteropServices;
  10
  11 namespace zipsharp
  12 {
  13         class ZipStream : Stream
  14         {
  15                 const int ZLIB_FILEFUNC_SEEK_CUR = 1;
  16                 const int ZLIB_FILEFUNC_SEEK_END = 2;
  17                 const int ZLIB_FILEFUNC_SEEK_SET = 0;
  18
  19                 bool canRead;
  20                 bool canSeek;
  21                 bool canWrite;
  22
  23                 public override bool CanRead {
  24                         get { return canRead; }
  25                 }
  26
  27                 public override bool CanSeek {
  28                         get { return canSeek; }
  29                 }
  30
  31                 public override bool CanWrite {
  32                         get { return canWrite; }
  33                 }
  34
  35                 public override bool CanTimeout {
  36                         get { return false; }
  37                 }
  38
  39                 private Stream DataStream {
  40                         get; set;
  41                 }
  42
  43                 public ZlibFileFuncDef32 IOFunctions32 {
  44                         get; set;
  45                 }
  46
  47                 public ZlibFileFuncDef64 IOFunctions64 {
  48                         get; set;
  49                 }
  50
  51                 public override long Length {
  52                         get { return DataStream.Length; }
  53                 }
  54
  55                 bool OwnsStream {
  56                         get; set;
  57                 }
  58
  59                 public override long Position {
  60                         get { return DataStream.Position; }
  61                         set { DataStream.Position = value; }
  62                 }
  63
  64                 public ZipStream (Stream dataStream, bool ownsStream)
  65                 {
  66                         // FIXME: Not necessarily true
  67                         canRead = true;
  68                         canSeek = true;
  69                         canWrite = true;
  70
  71                         DataStream = dataStream;
  72                         OwnsStream = ownsStream;
  73
  74                         ZlibFileFuncDef32 f32 = new ZlibFileFuncDef32 ();
  75                         f32.opaque = IntPtr.Zero;
  76                         f32.zclose_file = CloseFile_Native;
  77                         f32.zerror_file = TestError_Native;
  78                         f32.zopen_file = OpenFile_Native;
  79                         f32.zread_file = ReadFile_Native32;
  80                         f32.zseek_file = SeekFile_Native32;
  81                         f32.ztell_file = TellFile_Native32;
  82                         f32.zwrite_file = WriteFile_Native32;
  83                         IOFunctions32 = f32;
  84
  85                         ZlibFileFuncDef64 f64 = new ZlibFileFuncDef64 ();
  86                         f64.opaque = IntPtr.Zero;
  87                         f64.zclose_file = CloseFile_Native;
  88                         f64.zerror_file = TestError_Native;
  89                         f64.zopen_file = OpenFile_Native;
  90                         f64.zread_file = ReadFile_Native64;
  91                         f64.zseek_file = SeekFile_Native64;
  92                         f64.ztell_file = TellFile_Native64;
  93                         f64.zwrite_file = WriteFile_Native64;
  94                         IOFunctions64 = f64;
  95                 }
  96
  97                 protected override void Dispose(bool disposing)
  98                 {
  99                         if (!disposing)
 100                                 return;
 101
 102                         DataStream.Flush ();
 103                         if (OwnsStream)
 104                                 DataStream.Dispose ();
 105                 }
 106
 107                 public override void Flush()
 108                 {
 109                         DataStream.Flush ();
 110                 }
 111
 112                 public override int Read(byte[] buffer, int offset, int count)
 113                 {
 114                         return DataStream.Read (buffer, offset, count);
 115                 }
 116
 117                 public override long Seek(long offset, SeekOrigin origin)
 118                 {
 119                         DataStream.Seek (offset, origin);
 120                         return DataStream.Position;
 121                 }
 122
 123                 public override void SetLength(long value)
 124                 {
 125                         DataStream.SetLength (value);
 126                 }
 127
 128                 public override void Write(byte[] buffer, int offset, int count)
 129                 {
 130                         DataStream.Write (buffer, offset, count);
 131                         Flush ();
 132                 }
 133
 134                 int CloseFile_Native (IntPtr opaque, IntPtr stream)
 135                 {
 136                         Close ();
 137                         return 0;
 138                 }
 139
 140                 IntPtr OpenFile_Native (IntPtr opaque, string filename, int mode)
 141                 {
 142                         // always success. The stream is opened in managed code
 143                         return new IntPtr (1);
 144                 }
 145
 146                 unsafe uint ReadFile_Native32 (IntPtr opaque, IntPtr stream, IntPtr buffer, uint size)
 147                 {
 148                         return (uint) ReadFile_Native64 (opaque, stream, buffer, size);
 149                 }
 150
 151                 unsafe ulong ReadFile_Native64 (IntPtr opaque, IntPtr stream, IntPtr buffer, ulong size)
 152                 {
 153                         int count = (int) size;
 154                         byte[] b = new byte[count];
 155                         int read;
 156
 157                         try {
 158                                 read = Math.Max (0, Read (b, 0, count));
 159                                 byte* ptrBuffer = (byte*) buffer.ToPointer ();
 160                                 for (int i = 0; i < count && i < read; i ++)
 161                                         ptrBuffer[i] = b[i];
 162                         } catch {
 163                                 read = -1;
 164                         }
 165
 166                         return (ulong) read;
 167                 }
 168
 169                 int SeekFile_Native32 (IntPtr opaque, IntPtr stream, uint offset, int origin)
 170                 {
 171                         return (int) SeekFile_Native64 (opaque, stream, offset, origin);
 172                 }
 173
 174                 long SeekFile_Native64 (IntPtr opaque, IntPtr stream, ulong offset, int origin)
 175                 {
 176                         SeekOrigin seek;
 177                         if (origin == ZipStream.ZLIB_FILEFUNC_SEEK_CUR)
 178                                 seek = SeekOrigin.Current;
 179                         else if (origin == ZLIB_FILEFUNC_SEEK_END)
 180                                 seek = SeekOrigin.End;
 181                         else if (origin == ZLIB_FILEFUNC_SEEK_SET)
 182                                 seek = SeekOrigin.Begin;
 183                         else
 184                                 return -1;
 185
 186                         Seek ((long) offset, seek);
 187
 188                         return 0;
 189                 }
 190
 191                 int TellFile_Native32 (IntPtr opaque, IntPtr stream)
 192                 {
 193                         return (int) TellFile_Native64 (opaque, stream);
 194                 }
 195
 196                 long TellFile_Native64 (IntPtr opaque, IntPtr stream)
 197                 {
 198                         return Position;
 199                 }
 200
 201                 int TestError_Native (IntPtr opaque, IntPtr stream)
 202                 {
 203                         // No errors here.
 204                         return 0;
 205                 }
 206
 207                 unsafe uint WriteFile_Native32 (IntPtr opaque, IntPtr stream, IntPtr buffer, /* ulong */ uint size)
 208                 {
 209                         return (uint) WriteFile_Native64 (opaque, stream, buffer, size);
 210                 }
 211
 212                 unsafe ulong WriteFile_Native64 (IntPtr opaque, IntPtr stream, IntPtr buffer, /* ulong */ ulong size)
 213                 {
 214                         int count = (int) size;
 215                         byte[] b = new byte[count];
 216
 217                         byte* ptrBuffer = (byte*) buffer.ToPointer ();
 218                         for (int i = 0; i < count; i ++)
 219                                 b[i] = ptrBuffer[i];
 220
 221                         try {
 222                                 Write (b, 0, count);
 223                         } catch {
 224
 225                         }
 226
 227                         return (ulong) count;
 228                 }
 229         }
 230 }