formats.py

   1 import os, sys
   2 from support import pipe_through_command, escape, Tmp
   3 import rox
   4
   5 operations = []
   6 class Operation:
   7         add_extension = 0
   8
   9         def __init__(self, extension):
  10                 operations.append(self)
  11                 self.extension = extension
  12
  13         def can_handle(self, data):
  14                 return isinstance(data, FileData)
  15
  16         def save_to_stream(self, data, stream):
  17                 pipe_through_command(self.command, data.source, stream)
  18
  19 class Compress(Operation):
  20         "Compress a stream into another stream."
  21         add_extension = 1
  22
  23         def __init__(self, extension, command, type):
  24                 Operation.__init__(self, extension)
  25                 self.command = command
  26                 self.type = type
  27
  28         def __str__(self):
  29                 return 'Compress as .%s' % self.extension
  30
  31 class Decompress(Operation):
  32         "Decompress a stream into another stream."
  33         type = 'text/plain'
  34
  35         def __init__(self, extension, command):
  36                 Operation.__init__(self, extension)
  37                 self.command = command
  38
  39         def __str__(self):
  40                 return 'Decompress .%s' % self.extension
  41
  42 class Extract(Operation):
  43         "Extract an archive to a directory."
  44         type = 'inode/directory'
  45
  46         def __init__(self, extension, command):
  47                 "If command has a %s then the source path is inserted, else uses stdin."
  48                 Operation.__init__(self, extension)
  49                 self.command = command
  50
  51         def __str__(self):
  52                 return 'Extract from a .%s' % self.extension
  53
  54         def save_to_stream(self, data, stream):
  55                 raise Exception('This operation creates a directory, so you have '
  56                                 'to drag to a filer window on the local machine')
  57
  58         def save_to_file(self, data, path):
  59                 if os.path.exists(path):
  60                         if not os.path.isdir(path):
  61                                 raise Exception("'%s' already exists and is not a directory!" %
  62                                                 path)
  63                         if not rox.confirm('Directory already exists; extract into it?',
  64                                            g.STOCK_YES):
  65                                 raise Exception('Extraction aborted... try somewhere else')
  66                 if not os.path.exists(path):
  67                         os.mkdir(path)
  68                 os.chdir(path)
  69                 command = self.command
  70                 source = data.source
  71                 if command.find("'%s'") != -1:
  72                         # TODO: Handle path being '-'
  73                         command = command % escape(data.path)
  74                         source = None
  75                 pipe_through_command(command, source, None)
  76
  77 class Archive(Operation):
  78         "Create an archive from a directory."
  79         add_extension = 1
  80
  81         def __init__(self, extension, command, type):
  82                 assert command.find("'%s'") != -1
  83
  84                 Operation.__init__(self, extension)
  85                 self.command = command
  86                 self.type = type
  87
  88         def __str__(self):
  89                 return 'Create .%s archive' % self.extension
  90
  91         def can_handle(self, data):
  92                 return isinstance(data, DirData)
  93
  94         def save_to_stream(self, data, stream):
  95                 os.chdir(os.path.dirname(data.path))
  96                 command = self.command % escape(os.path.basename(data.path))
  97                 pipe_through_command(command, None, stream)
  98
  99 tgz = Extract('tgz',    "gunzip -c - | tar xf -")
 100 tbz = Extract('tar.bz2', "bunzip2 -c - | tar xf -")
 101 jar = Extract('jar',    "unzip -q -")
 102 rar = Extract('rar',    "rar x -")
 103 tar = Extract('tar',    "tar xf -")
 104 rpm = Extract('rpm',    "rpm2cpio - | cpio -id --quiet")
 105 cpio = Extract('cpio',  "cpio -id --quiet")
 106 deb = Extract('deb', "ar x '%s'")
 107 zip = Extract('zip', "unzip -q '%s'")
 108
 109 make_tgz = Archive('tgz', "tar cf - '%s' | gzip", 'application/x-compressed-tar')
 110 Archive('tar.gz',  "tar cf - '%s' | gzip", 'application/x-compressed-tar')
 111 Archive('tar.bz',  "tar cf - '%s' | bzip2", 'application/x-bzip-compressed-tar')
 112 Archive('tar.bz2', "tar cf - '%s' | bzip2", 'application/x-bzip-compressed-tar')
 113 Archive('zip',     "zip -qr - '%s'", 'application/zip'),
 114 Archive('jar',     "zip -qr - '%s'", 'application/x-jar')
 115 Archive('tar',     "tar cf - '%s'", 'application/x-tar')
 116
 117 # Note: these go afterwards so that .tar.gz matches before .gz
 118 make_gz = Compress('gz', "gzip -c -", 'application/x-gzip')
 119 Compress('bz2', "bzip2 -c -", 'application/x-bzip')
 120
 121 gz = Decompress('gz',   "gunzip -c -")
 122 bz2 = Decompress('bz2',  "bunzip2 -ck -")
 123
 124
 125 # Can bzip2 read bzip files?
 126
 127 aliases = {
 128         'tar.gz': 'tgz',
 129         'tar.bz': 'tar.bz2',
 130         'bz': 'bz2'
 131 }
 132
 133 known_extensions = {}
 134 for x in operations:
 135         try:
 136                 known_extensions[x.extension] = None
 137         except AttributeError:
 138                 pass
 139
 140 class FileData:
 141         "A file on the local filesystem."
 142         def __init__(self, path):
 143                 self.path = path
 144
 145                 if path == '-':
 146                         source = sys.stdin
 147                 else:
 148                         try:
 149                                 source = file(path)
 150                         except:
 151                                 rox.report_exception()
 152                                 sys.exit(1)
 153
 154                 self.path = path
 155                 start = source.read(300)
 156                 try:
 157                         source.seek(0)
 158                         self.source = source
 159                 except:
 160                         # Input is not a regular, local, seekable file, so copy it
 161                         # to a local temp file.
 162                         import shutil
 163                         tmp = Tmp()
 164                         tmp.write(start)
 165                         tmp.flush()
 166                         shutil.copyfileobj(source, tmp)
 167                         self.source = tmp
 168                         self.source.seek(0)
 169                 self.default = self.guess_format(start)
 170
 171                 if path == '-':
 172                         name = 'Data'
 173                 else:
 174                         name = path
 175                         for ext in known_extensions:
 176                                 if path.endswith('.' + ext):
 177                                         new = path[:-len(ext)-1]
 178                                         if len(new) < len(name):
 179                                                 name = new
 180                 if self.default.add_extension:
 181                         name += '.' + self.default.extension
 182                 self.default_name = name
 183
 184         def guess_format(self, data):
 185                 "Return a good default Operation, judging by the first 300 bytes or so."
 186                 l = len(data)
 187                 def string(offset, match):
 188                         return data[offset:offset + len(match)] == match
 189                 def short(offset, match):
 190                         if l > offset + 1:
 191                                 a = data[offset]
 192                                 b = data[offset + 1]
 193                                 return ((a == match & 0xff) and (b == (match >> 8))) or \
 194                                         (b == match & 0xff) and (a == (match >> 8))
 195                         return 0
 196
 197                 # Archives
 198                 if string(257, 'ustar\0') or string(257, 'ustar\040\040\0'):
 199                         return tar
 200                 if short(0, 070707) or short(0, 0143561) or string(0, '070707') or \
 201                    string(0, '070701') or string(0, '070702'):
 202                         return cpio
 203                 if string(0, '!<arch>') or string(0, '\\<ar>') or string(0, '<ar>'):
 204                         if string(7, '\ndebian'):
 205                                 return deb
 206                 if string(0, 'Rar!'): return rar
 207                 if string(0, 'PK\003\004'): return zip
 208
 209                 # Compressed streams
 210                 if string(0, '\037\213'):
 211                         if self.path.endswith('.tar.gz') or self.path.endswith('.tgz'):
 212                                 return tgz
 213                         return gz
 214                 if string(0, 'BZh') or string(0, 'BZ'):
 215                         if self.path.endswith('.tar.bz') or self.path.endswith('.tar.bz2') or \
 216                            self.path.endswith('.tbz') or self.path.endswith('.tbz2'):
 217                                 return tbz
 218                         return bz2
 219
 220                 return make_gz
 221
 222 class DirData:
 223         def __init__(self, path):
 224                 self.path = path
 225                 self.default = make_tgz
 226                 self.default_name = path + '.' + self.default.extension