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                         command = command % escape(source.name)
  73                         source = None
  74                 try:
  75                         pipe_through_command(command, source, None)
  76                 finally:
  77                         try:
  78                                 os.rmdir(path)  # Will only succeed if it's empty
  79                         except:
  80                                 pass
  81                 # If we created only a single subdirectory, move it up.
  82                 dirs = os.listdir(path)
  83                 if len(dirs) != 1:
  84                         return
  85                 dir = dirs[0]
  86                 unneeded_path = os.path.join(path, dir)
  87                 if not os.path.isdir(unneeded_path):
  88                         return
  89                 import random
  90                 tmp_path = os.path.join(path, 'tmp-' + `random.randint(0, 100000)`)
  91                 os.rename(unneeded_path, tmp_path)
  92                 for file in os.listdir(tmp_path):
  93                         os.rename(os.path.join(tmp_path, file), os.path.join(path, file))
  94                 os.rmdir(tmp_path)
  95
  96 class Archive(Operation):
  97         "Create an archive from a directory."
  98         add_extension = 1
  99
 100         def __init__(self, extension, command, type):
 101                 assert command.find("'%s'") != -1
 102
 103                 Operation.__init__(self, extension)
 104                 self.command = command
 105                 self.type = type
 106
 107         def __str__(self):
 108                 return 'Create .%s archive' % self.extension
 109
 110         def can_handle(self, data):
 111                 return isinstance(data, DirData)
 112
 113         def save_to_stream(self, data, stream):
 114                 os.chdir(os.path.dirname(data.path))
 115                 command = self.command % escape(os.path.basename(data.path))
 116                 pipe_through_command(command, None, stream)
 117
 118 tgz = Extract('tgz',    "gunzip -c - | tar xf -")
 119 tbz = Extract('tar.bz2', "bunzip2 -c - | tar xf -")
 120 jar = Extract('jar',    "unzip -q -")
 121 rar = Extract('rar',    "rar x -")
 122 tar = Extract('tar',    "tar xf -")
 123 rpm = Extract('rpm',    "rpm2cpio - | cpio -id --quiet")
 124 cpio = Extract('cpio',  "cpio -id --quiet")
 125 deb = Extract('deb', "ar x '%s'")
 126 zip = Extract('zip', "unzip -q '%s'")
 127
 128 make_tgz = Archive('tgz', "tar cf - '%s' | gzip", 'application/x-compressed-tar')
 129 Archive('tar.gz',  "tar cf - '%s' | gzip", 'application/x-compressed-tar')
 130 Archive('tar.bz',  "tar cf - '%s' | bzip2", 'application/x-bzip-compressed-tar')
 131 Archive('tar.bz2', "tar cf - '%s' | bzip2", 'application/x-bzip-compressed-tar')
 132 Archive('zip',     "zip -qr - '%s'", 'application/zip'),
 133 Archive('jar',     "zip -qr - '%s'", 'application/x-jar')
 134 Archive('tar',     "tar cf - '%s'", 'application/x-tar')
 135
 136 # Note: these go afterwards so that .tar.gz matches before .gz
 137 make_gz = Compress('gz', "gzip -c -", 'application/x-gzip')
 138 Compress('bz2', "bzip2 -c -", 'application/x-bzip')
 139
 140 gz = Decompress('gz',   "gunzip -c -")
 141 bz2 = Decompress('bz2',  "bunzip2 -ck -")
 142
 143
 144 # Can bzip2 read bzip files?
 145
 146 aliases = {
 147         'tar.gz': 'tgz',
 148         'tar.bz': 'tar.bz2',
 149         'bz': 'bz2'
 150 }
 151
 152 known_extensions = {}
 153 for x in operations:
 154         try:
 155                 known_extensions[x.extension] = None
 156         except AttributeError:
 157                 pass
 158
 159 class FileData:
 160         "A file on the local filesystem."
 161         def __init__(self, path):
 162                 self.path = path
 163
 164                 if path == '-':
 165                         source = sys.stdin
 166                 else:
 167                         try:
 168                                 source = file(path)
 169                         except:
 170                                 rox.report_exception()
 171                                 sys.exit(1)
 172
 173                 self.path = path
 174                 start = source.read(300)
 175                 try:
 176                         source.seek(0)
 177                         self.source = source
 178                 except:
 179                         # Input is not a regular, local, seekable file, so copy it
 180                         # to a local temp file.
 181                         import shutil
 182                         tmp = Tmp()
 183                         tmp.write(start)
 184                         tmp.flush()
 185                         shutil.copyfileobj(source, tmp)
 186                         self.source = tmp
 187                         self.source.seek(0)
 188                 self.default = self.guess_format(start)
 189
 190                 if path == '-':
 191                         name = 'Data'
 192                 else:
 193                         name = path
 194                         for ext in known_extensions:
 195                                 if path.endswith('.' + ext):
 196                                         new = path[:-len(ext)-1]
 197                                         if len(new) < len(name):
 198                                                 name = new
 199                 if self.default.add_extension:
 200                         name += '.' + self.default.extension
 201                 self.default_name = name
 202
 203         def guess_format(self, data):
 204                 "Return a good default Operation, judging by the first 300 bytes or so."
 205                 l = len(data)
 206                 def string(offset, match):
 207                         return data[offset:offset + len(match)] == match
 208                 def short(offset, match):
 209                         if l > offset + 1:
 210                                 a = data[offset]
 211                                 b = data[offset + 1]
 212                                 return ((a == match & 0xff) and (b == (match >> 8))) or \
 213                                         (b == match & 0xff) and (a == (match >> 8))
 214                         return 0
 215
 216                 # Archives
 217                 if string(257, 'ustar\0') or string(257, 'ustar\040\040\0'):
 218                         return tar
 219                 if short(0, 070707) or short(0, 0143561) or string(0, '070707') or \
 220                    string(0, '070701') or string(0, '070702'):
 221                         return cpio
 222                 if string(0, '!<arch>') or string(0, '\\<ar>') or string(0, '<ar>'):
 223                         if string(7, '\ndebian'):
 224                                 return deb
 225                 if string(0, 'Rar!'): return rar
 226                 if string(0, 'PK\003\004'): return zip
 227
 228                 # Compressed streams
 229                 if string(0, '\037\213'):
 230                         if self.path.endswith('.tar.gz') or self.path.endswith('.tgz'):
 231                                 return tgz
 232                         return gz
 233                 if string(0, 'BZh') or string(0, 'BZ'):
 234                         if self.path.endswith('.tar.bz') or self.path.endswith('.tar.bz2') or \
 235                            self.path.endswith('.tbz') or self.path.endswith('.tbz2'):
 236                                 return tbz
 237                         return bz2
 238
 239                 return make_gz
 240
 241 class DirData:
 242         def __init__(self, path):
 243                 self.path = path
 244                 self.default = make_tgz
 245                 self.default_name = path + '.' + self.default.extension