tools/tf/FileType.cs

   1 //
   2 // filetype.cs
   3 //
   4 // Authors:
   5 //      Joel Reed (joelwreed@gmail.com)
   6 //
   7
   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 Mono.Unix;
  33
  34 class FileTypeDatabase
  35 {
  36         [DllImport("magic")]
  37         private extern static IntPtr magic_open(int flags);
  38
  39         [DllImport("magic")]
  40         private extern static void magic_close(IntPtr magic_cookie);
  41
  42         [DllImport("magic")]
  43         private extern static IntPtr magic_file(IntPtr magic_cookie, string filename);
  44
  45         [DllImport("magic")]
  46         private extern static int magic_load(IntPtr magic_cookie, IntPtr x);
  47
  48         private static IntPtr _magic = IntPtr.Zero;
  49
  50         static FileTypeDatabase()
  51         {
  52                 _magic = magic_open(0);
  53                 if (_magic == IntPtr.Zero)
  54                         {
  55                                 Console.WriteLine("Warning: failed to open libmagic database");
  56                                 return;
  57                         }
  58
  59                 magic_load(_magic, IntPtr.Zero);
  60         }
  61
  62         ~FileTypeDatabase()
  63         {
  64                 if (_magic != IntPtr.Zero)
  65                         magic_close(_magic);
  66         }
  67
  68         public static bool ShouldBeExecutable(string filename)
  69         {
  70                 if (_magic == IntPtr.Zero) return false;
  71                 string desc = Marshal.PtrToStringAuto(magic_file(_magic, filename));
  72                 if (String.IsNullOrEmpty(desc))
  73                         {
  74                                 Console.WriteLine("Error querying file type for " + filename);
  75                                 return false;
  76                         }
  77
  78                 return desc.Contains("executable");
  79         }
  80
  81         public static void MakeExecutable(string filename)
  82         {
  83                 Mono.Unix.Native.Stat stat;
  84                 if (0 == Mono.Unix.Native.Syscall.stat(filename, out stat))
  85                         {
  86                                 Mono.Unix.Native.FilePermissions fp = stat.st_mode | Mono.Unix.Native.FilePermissions.S_IXUSR;
  87                                 Mono.Unix.Native.Syscall.chmod(filename, fp);
  88                         }
  89         }
  90 }
  91