--- /dev/null
+#
+# tempfile - manipulates temporary files
+#
+# $Id: tempfile.rb 19833 2008-10-18 10:32:26Z matz $
+#
+
+require 'delegate'
+require 'tmpdir'
+require 'thread'
+
+# A class for managing temporary files. This library is written to be
+# thread safe.
+class Tempfile < DelegateClass(File)
+ MAX_TRY = 10
+ @@cleanlist = []
+ @@lock = Mutex.new
+
+ # Creates a temporary file of mode 0600 in the temporary directory,
+ # opens it with mode "w+", and returns a Tempfile object which
+ # represents the created temporary file. A Tempfile object can be
+ # treated just like a normal File object.
+ #
+ # The basename parameter is used to determine the name of a
+ # temporary file. If an Array is given, the first element is used
+ # as prefix string and the second as suffix string, respectively.
+ # Otherwise it is treated as prefix string.
+ #
+ # 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)
+ def initialize(basename, *rest)
+ # I wish keyword argument settled soon.
+ if opts = Hash.try_convert(rest[-1])
+ rest.pop
+ end
+ tmpdir = rest[0] || Dir::tmpdir
+ if $SAFE > 0 and tmpdir.tainted?
+ tmpdir = '/tmp'
+ end
+
+ lock = tmpname = nil
+ n = failure = 0
+ @@lock.synchronize {
+ begin
+ begin
+ tmpname = File.join(tmpdir, make_tmpname(basename, n))
+ lock = tmpname + '.lock'
+ n += 1
+ end while @@cleanlist.include?(tmpname) or
+ File.exist?(lock) or File.exist?(tmpname)
+ Dir.mkdir(lock)
+ rescue
+ failure += 1
+ retry if failure < MAX_TRY
+ raise "cannot generate tempfile `%s'" % tmpname
+ end
+ }
+
+ @data = [tmpname]
+ @clean_proc = Tempfile.callback(@data)
+ ObjectSpace.define_finalizer(self, @clean_proc)
+
+ if opts.nil?
+ opts = []
+ else
+ opts = [opts]
+ end
+ @tmpfile = File.open(tmpname, File::RDWR|File::CREAT|File::EXCL, 0600, *opts)
+ @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
+
+ def make_tmpname(basename, n)
+ case basename
+ when Array
+ prefix, suffix = *basename
+ else
+ prefix, suffix = basename, ''
+ end
+
+ t = Time.now.strftime("%Y%m%d")
+ path = "#{prefix}#{t}-#{$$}-#{rand(0x100000000).to_s(36)}-#{n}#{suffix}"
+ end
+ private :make_tmpname
+
+ # Opens or reopens the file with mode "r+".
+ def open
+ @tmpfile.close if @tmpfile
+ @tmpfile = File.open(@tmpname, 'r+')
+ @data[1] = @tmpfile
+ __setobj__(@tmpfile)
+ end
+
+ def _close # :nodoc:
+ @tmpfile.close if @tmpfile
+ @tmpfile = nil
+ @data[1] = nil if @data
+ end
+ protected :_close
+
+ #Closes the file. If the optional flag is true, unlinks the file
+ # after closing.
+ #
+ # If you don't explicitly unlink the temporary file, the removal
+ # will be delayed until the object is finalized.
+ def close(unlink_now=false)
+ if unlink_now
+ close!
+ else
+ _close
+ end
+ end
+
+ # Closes and unlinks the file.
+ def close!
+ _close
+ @clean_proc.call
+ ObjectSpace.undefine_finalizer(self)
+ @data = @tmpname = nil
+ end
+
+ # Unlinks the file. On UNIX-like systems, it is often a good idea
+ # to unlink a temporary file immediately after creating and opening
+ # it, because it leaves other programs zero chance to access the
+ # file.
+ def unlink
+ # keep this order for thread safeness
+ begin
+ File.unlink(@tmpname) if File.exist?(@tmpname)
+ @@cleanlist.delete(@tmpname)
+ @data = @tmpname = nil
+ ObjectSpace.undefine_finalizer(self)
+ rescue Errno::EACCES
+ # may not be able to unlink on Windows; just ignore
+ end
+ end
+ alias delete unlink
+
+ # Returns the full path name of the temporary file.
+ def path
+ @tmpname
+ end
+
+ # Returns the size of the temporary file. As a side effect, the IO
+ # buffer is flushed before determining the size.
+ def size
+ if @tmpfile
+ @tmpfile.flush
+ @tmpfile.stat.size
+ else
+ 0
+ end
+ end
+ alias length size
+
+ class << self
+ def callback(data) # :nodoc:
+ pid = $$
+ Proc.new {
+ 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
+
+ # 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.
+ def open(*args)
+ tempfile = new(*args)
+
+ if block_given?
+ begin
+ yield(tempfile)
+ ensure
+ tempfile.close
+ end
+ else
+ tempfile
+ end
+ end
+ end
+end
+
+if __FILE__ == $0
+# $DEBUG = true
+ f = Tempfile.new("foo")
+ f.print("foo\n")
+ f.close
+ f.open
+ p f.gets # => "foo\n"
+ f.close!
+end
OSDN Git Service
