Class: BugFix::Tempfile

Inherits:
File
  • Object
show all
Defined in:
lib/zip/tempfile_bugfixed.rb

Overview

A class for managing temporary files. This library is written to be thread safe.

Constant Summary collapse

MAX_TRY =
10
@@cleanlist =
[]

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(basename, tmpdir = Dir::tmpdir) ⇒ Tempfile

Creates a temporary file of mode 0600 in the temporary directory whose name is basename.pid.n and opens with mode “w+”. A Tempfile object works just like a File object.

If tmpdir is omitted, the temporary directory is determined by Dir::tmpdir provided by ‘tmpdir.rb’. When $SAFE > 0 and the given tmpdir is tainted, it uses /tmp. (Note that ENV values are tainted by default)



26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
# File 'lib/zip/tempfile_bugfixed.rb', line 26

def initialize(basename, tmpdir=Dir::tmpdir)
  if $SAFE > 0 and tmpdir.tainted?
    tmpdir = '/tmp'
  end

  lock = nil
  n = failure = 0

  begin
    Thread.critical = true

    begin
      tmpname = sprintf('%s/%s%d.%d', tmpdir, basename, $$, n)
      lock = tmpname + '.lock'
      n += 1
    end while @@cleanlist.include?(tmpname) ||
    ::File.exist?(lock) || ::File.exist?(tmpname)

    Dir.mkdir(lock)
  rescue
    failure += 1
    retry if failure < MAX_TRY
    raise "cannot generate tempfile `%s'" % tmpname
  ensure
    Thread.critical = false
  end

  @data = [tmpname]
  @clean_proc = Tempfile.callback(@data)
  ObjectSpace.define_finalizer(self, @clean_proc)

  @tmpfile = ::File.open(tmpname, ::File::RDWR|::File::CREAT|::File::EXCL, 0600)
  @tmpname = tmpname
  @@cleanlist << @tmpname
  @data[1] = @tmpfile
  @data[2] = @@cleanlist

  super(@tmpfile)

  # Now we have all the File/IO methods defined, you must not
  # carelessly put bare puts(), etc. after this.

  Dir.rmdir(lock)
end

Class Method Details

.callback(data) ⇒ Object

:nodoc:



144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
# File 'lib/zip/tempfile_bugfixed.rb', line 144

def callback(data)	# :nodoc:
  pid = $$
  lambda{
    if pid == $$ 
      path, tmpfile, cleanlist = *data

      print "removing ", path, "..." if $DEBUG

      tmpfile.close if tmpfile

      # keep this order for thread safeness
      ::File.unlink(path) if ::File.exist?(path)
      cleanlist.delete(path) if cleanlist

      print "done\n" if $DEBUG
    end
  }
end

.open(*args) ⇒ Object

If no block is given, this is a synonym for new().

If a block is given, it will be passed tempfile as an argument, and the tempfile will automatically be closed when the block terminates. In this case, open() returns nil.



168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
# File 'lib/zip/tempfile_bugfixed.rb', line 168

def open(*args)
  tempfile = new(*args)

  if block_given?
    begin
      yield(tempfile)
    ensure
      tempfile.close
    end

    nil
  else
    tempfile
  end
end

Instance Method Details

#__setobj__(obj) ⇒ Object



117
118
119
# File 'lib/zip/tempfile_bugfixed.rb', line 117

def __setobj__(obj)
  @_dc_obj = obj
end

#close(unlink_now = false) ⇒ Object

Closes the file. If the optional flag is true, unlinks the file after closing.

If you don’t explicitly unlink the temporary file, the removal will be delayed until the object is finalized.



90
91
92
93
94
95
96
# File 'lib/zip/tempfile_bugfixed.rb', line 90

def close(unlink_now=false)
  if unlink_now
    close!
  else
    _close
  end
end

#close!Object

Closes and unlinks the file.



99
100
101
102
103
# File 'lib/zip/tempfile_bugfixed.rb', line 99

def close!
  _close
  @clean_proc.call
  ObjectSpace.undefine_finalizer(self)
end

#openObject

Opens or reopens the file with mode “r+”.



72
73
74
75
76
77
# File 'lib/zip/tempfile_bugfixed.rb', line 72

def open
  @tmpfile.close if @tmpfile
  @tmpfile = ::File.open(@tmpname, 'r+')
  @data[1] = @tmpfile
  __setobj__(@tmpfile)
end

#pathObject

Returns the full path name of the temporary file.



127
128
129
# File 'lib/zip/tempfile_bugfixed.rb', line 127

def path
  @tmpname
end

#sizeObject Also known as: length

Returns the size of the temporary file. As a side effect, the IO buffer is flushed before determining the size.



133
134
135
136
137
138
139
140
# File 'lib/zip/tempfile_bugfixed.rb', line 133

def size
  if @tmpfile
    @tmpfile.flush
    @tmpfile.stat.size
  else
    0
  end
end

Unlinks the file. On UNIX-like systems, it is often a good idea to unlink a temporary file immediately after creating and opening it, because it leaves other programs zero chance to access the file.



109
110
111
112
113
# File 'lib/zip/tempfile_bugfixed.rb', line 109

def unlink
  # keep this order for thread safeness
  ::File.unlink(@tmpname) if ::File.exist?(@tmpname)
  @@cleanlist.delete(@tmpname) if @@cleanlist
end