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-rw-r--r--trunk/lib/rubygems/package/f_sync_dir.rb24
-rw-r--r--trunk/lib/rubygems/package/tar_header.rb245
-rw-r--r--trunk/lib/rubygems/package/tar_input.rb219
-rw-r--r--trunk/lib/rubygems/package/tar_output.rb143
-rw-r--r--trunk/lib/rubygems/package/tar_reader.rb86
-rw-r--r--trunk/lib/rubygems/package/tar_reader/entry.rb99
-rw-r--r--trunk/lib/rubygems/package/tar_writer.rb180
7 files changed, 996 insertions, 0 deletions
diff --git a/trunk/lib/rubygems/package/f_sync_dir.rb b/trunk/lib/rubygems/package/f_sync_dir.rb
new file mode 100644
index 0000000000..3e2e4a59a8
--- /dev/null
+++ b/trunk/lib/rubygems/package/f_sync_dir.rb
@@ -0,0 +1,24 @@
+#++
+# Copyright (C) 2004 Mauricio Julio Fernández Pradier
+# See LICENSE.txt for additional licensing information.
+#--
+
+require 'rubygems/package'
+
+module Gem::Package::FSyncDir
+
+ private
+
+ ##
+ # make sure this hits the disc
+
+ def fsync_dir(dirname)
+ dir = open dirname, 'r'
+ dir.fsync
+ rescue # ignore IOError if it's an unpatched (old) Ruby
+ ensure
+ dir.close if dir rescue nil
+ end
+
+end
+
diff --git a/trunk/lib/rubygems/package/tar_header.rb b/trunk/lib/rubygems/package/tar_header.rb
new file mode 100644
index 0000000000..c194cc0530
--- /dev/null
+++ b/trunk/lib/rubygems/package/tar_header.rb
@@ -0,0 +1,245 @@
+#++
+# Copyright (C) 2004 Mauricio Julio Fernández Pradier
+# See LICENSE.txt for additional licensing information.
+#--
+
+require 'rubygems/package'
+
+##
+#--
+# struct tarfile_entry_posix {
+# char name[100]; # ASCII + (Z unless filled)
+# char mode[8]; # 0 padded, octal, null
+# char uid[8]; # ditto
+# char gid[8]; # ditto
+# char size[12]; # 0 padded, octal, null
+# char mtime[12]; # 0 padded, octal, null
+# char checksum[8]; # 0 padded, octal, null, space
+# char typeflag[1]; # file: "0" dir: "5"
+# char linkname[100]; # ASCII + (Z unless filled)
+# char magic[6]; # "ustar\0"
+# char version[2]; # "00"
+# char uname[32]; # ASCIIZ
+# char gname[32]; # ASCIIZ
+# char devmajor[8]; # 0 padded, octal, null
+# char devminor[8]; # o padded, octal, null
+# char prefix[155]; # ASCII + (Z unless filled)
+# };
+#++
+
+class Gem::Package::TarHeader
+
+ FIELDS = [
+ :checksum,
+ :devmajor,
+ :devminor,
+ :gid,
+ :gname,
+ :linkname,
+ :magic,
+ :mode,
+ :mtime,
+ :name,
+ :prefix,
+ :size,
+ :typeflag,
+ :uid,
+ :uname,
+ :version,
+ ]
+
+ PACK_FORMAT = 'a100' + # name
+ 'a8' + # mode
+ 'a8' + # uid
+ 'a8' + # gid
+ 'a12' + # size
+ 'a12' + # mtime
+ 'a7a' + # chksum
+ 'a' + # typeflag
+ 'a100' + # linkname
+ 'a6' + # magic
+ 'a2' + # version
+ 'a32' + # uname
+ 'a32' + # gname
+ 'a8' + # devmajor
+ 'a8' + # devminor
+ 'a155' # prefix
+
+ UNPACK_FORMAT = 'A100' + # name
+ 'A8' + # mode
+ 'A8' + # uid
+ 'A8' + # gid
+ 'A12' + # size
+ 'A12' + # mtime
+ 'A8' + # checksum
+ 'A' + # typeflag
+ 'A100' + # linkname
+ 'A6' + # magic
+ 'A2' + # version
+ 'A32' + # uname
+ 'A32' + # gname
+ 'A8' + # devmajor
+ 'A8' + # devminor
+ 'A155' # prefix
+
+ attr_reader(*FIELDS)
+
+ def self.from(stream)
+ header = stream.read 512
+ empty = (header == "\0" * 512)
+
+ fields = header.unpack UNPACK_FORMAT
+
+ name = fields.shift
+ mode = fields.shift.oct
+ uid = fields.shift.oct
+ gid = fields.shift.oct
+ size = fields.shift.oct
+ mtime = fields.shift.oct
+ checksum = fields.shift.oct
+ typeflag = fields.shift
+ linkname = fields.shift
+ magic = fields.shift
+ version = fields.shift.oct
+ uname = fields.shift
+ gname = fields.shift
+ devmajor = fields.shift.oct
+ devminor = fields.shift.oct
+ prefix = fields.shift
+
+ new :name => name,
+ :mode => mode,
+ :uid => uid,
+ :gid => gid,
+ :size => size,
+ :mtime => mtime,
+ :checksum => checksum,
+ :typeflag => typeflag,
+ :linkname => linkname,
+ :magic => magic,
+ :version => version,
+ :uname => uname,
+ :gname => gname,
+ :devmajor => devmajor,
+ :devminor => devminor,
+ :prefix => prefix,
+
+ :empty => empty
+
+ # HACK unfactor for Rubinius
+ #new :name => fields.shift,
+ # :mode => fields.shift.oct,
+ # :uid => fields.shift.oct,
+ # :gid => fields.shift.oct,
+ # :size => fields.shift.oct,
+ # :mtime => fields.shift.oct,
+ # :checksum => fields.shift.oct,
+ # :typeflag => fields.shift,
+ # :linkname => fields.shift,
+ # :magic => fields.shift,
+ # :version => fields.shift.oct,
+ # :uname => fields.shift,
+ # :gname => fields.shift,
+ # :devmajor => fields.shift.oct,
+ # :devminor => fields.shift.oct,
+ # :prefix => fields.shift,
+
+ # :empty => empty
+ end
+
+ def initialize(vals)
+ unless vals[:name] && vals[:size] && vals[:prefix] && vals[:mode] then
+ raise ArgumentError, ":name, :size, :prefix and :mode required"
+ end
+
+ vals[:uid] ||= 0
+ vals[:gid] ||= 0
+ vals[:mtime] ||= 0
+ vals[:checksum] ||= ""
+ vals[:typeflag] ||= "0"
+ vals[:magic] ||= "ustar"
+ vals[:version] ||= "00"
+ vals[:uname] ||= "wheel"
+ vals[:gname] ||= "wheel"
+ vals[:devmajor] ||= 0
+ vals[:devminor] ||= 0
+
+ FIELDS.each do |name|
+ instance_variable_set "@#{name}", vals[name]
+ end
+
+ @empty = vals[:empty]
+ end
+
+ def empty?
+ @empty
+ end
+
+ def ==(other)
+ self.class === other and
+ @checksum == other.checksum and
+ @devmajor == other.devmajor and
+ @devminor == other.devminor and
+ @gid == other.gid and
+ @gname == other.gname and
+ @linkname == other.linkname and
+ @magic == other.magic and
+ @mode == other.mode and
+ @mtime == other.mtime and
+ @name == other.name and
+ @prefix == other.prefix and
+ @size == other.size and
+ @typeflag == other.typeflag and
+ @uid == other.uid and
+ @uname == other.uname and
+ @version == other.version
+ end
+
+ def to_s
+ update_checksum
+ header
+ end
+
+ def update_checksum
+ header = header " " * 8
+ @checksum = oct calculate_checksum(header), 6
+ end
+
+ private
+
+ def calculate_checksum(header)
+ header.unpack("C*").inject { |a, b| a + b }
+ end
+
+ def header(checksum = @checksum)
+ header = [
+ name,
+ oct(mode, 7),
+ oct(uid, 7),
+ oct(gid, 7),
+ oct(size, 11),
+ oct(mtime, 11),
+ checksum,
+ " ",
+ typeflag,
+ linkname,
+ magic,
+ oct(version, 2),
+ uname,
+ gname,
+ oct(devmajor, 7),
+ oct(devminor, 7),
+ prefix
+ ]
+
+ header = header.pack PACK_FORMAT
+
+ header << ("\0" * ((512 - header.size) % 512))
+ end
+
+ def oct(num, len)
+ "%0#{len}o" % num
+ end
+
+end
+
diff --git a/trunk/lib/rubygems/package/tar_input.rb b/trunk/lib/rubygems/package/tar_input.rb
new file mode 100644
index 0000000000..2ed3d6b772
--- /dev/null
+++ b/trunk/lib/rubygems/package/tar_input.rb
@@ -0,0 +1,219 @@
+#++
+# Copyright (C) 2004 Mauricio Julio Fernández Pradier
+# See LICENSE.txt for additional licensing information.
+#--
+
+require 'rubygems/package'
+
+class Gem::Package::TarInput
+
+ include Gem::Package::FSyncDir
+ include Enumerable
+
+ attr_reader :metadata
+
+ private_class_method :new
+
+ def self.open(io, security_policy = nil, &block)
+ is = new io, security_policy
+
+ yield is
+ ensure
+ is.close if is
+ end
+
+ def initialize(io, security_policy = nil)
+ @io = io
+ @tarreader = Gem::Package::TarReader.new @io
+ has_meta = false
+
+ data_sig, meta_sig, data_dgst, meta_dgst = nil, nil, nil, nil
+ dgst_algo = security_policy ? Gem::Security::OPT[:dgst_algo] : nil
+
+ @tarreader.each do |entry|
+ case entry.full_name
+ when "metadata"
+ @metadata = load_gemspec entry.read
+ has_meta = true
+ when "metadata.gz"
+ begin
+ # if we have a security_policy, then pre-read the metadata file
+ # and calculate it's digest
+ sio = nil
+ if security_policy
+ Gem.ensure_ssl_available
+ sio = StringIO.new(entry.read)
+ meta_dgst = dgst_algo.digest(sio.string)
+ sio.rewind
+ end
+
+ gzis = Zlib::GzipReader.new(sio || entry)
+ # YAML wants an instance of IO
+ @metadata = load_gemspec(gzis)
+ has_meta = true
+ ensure
+ gzis.close unless gzis.nil?
+ end
+ when 'metadata.gz.sig'
+ meta_sig = entry.read
+ when 'data.tar.gz.sig'
+ data_sig = entry.read
+ when 'data.tar.gz'
+ if security_policy
+ Gem.ensure_ssl_available
+ data_dgst = dgst_algo.digest(entry.read)
+ end
+ end
+ end
+
+ if security_policy then
+ Gem.ensure_ssl_available
+
+ # map trust policy from string to actual class (or a serialized YAML
+ # file, if that exists)
+ if String === security_policy then
+ if Gem::Security::Policy.key? security_policy then
+ # load one of the pre-defined security policies
+ security_policy = Gem::Security::Policy[security_policy]
+ elsif File.exist? security_policy then
+ # FIXME: this doesn't work yet
+ security_policy = YAML.load File.read(security_policy)
+ else
+ raise Gem::Exception, "Unknown trust policy '#{security_policy}'"
+ end
+ end
+
+ if data_sig && data_dgst && meta_sig && meta_dgst then
+ # the user has a trust policy, and we have a signed gem
+ # file, so use the trust policy to verify the gem signature
+
+ begin
+ security_policy.verify_gem(data_sig, data_dgst, @metadata.cert_chain)
+ rescue Exception => e
+ raise "Couldn't verify data signature: #{e}"
+ end
+
+ begin
+ security_policy.verify_gem(meta_sig, meta_dgst, @metadata.cert_chain)
+ rescue Exception => e
+ raise "Couldn't verify metadata signature: #{e}"
+ end
+ elsif security_policy.only_signed
+ raise Gem::Exception, "Unsigned gem"
+ else
+ # FIXME: should display warning here (trust policy, but
+ # either unsigned or badly signed gem file)
+ end
+ end
+
+ @tarreader.rewind
+ @fileops = Gem::FileOperations.new
+
+ raise Gem::Package::FormatError, "No metadata found!" unless has_meta
+ end
+
+ def close
+ @io.close
+ @tarreader.close
+ end
+
+ def each(&block)
+ @tarreader.each do |entry|
+ next unless entry.full_name == "data.tar.gz"
+ is = zipped_stream entry
+
+ begin
+ Gem::Package::TarReader.new is do |inner|
+ inner.each(&block)
+ end
+ ensure
+ is.close if is
+ end
+ end
+
+ @tarreader.rewind
+ end
+
+ def extract_entry(destdir, entry, expected_md5sum = nil)
+ if entry.directory? then
+ dest = File.join(destdir, entry.full_name)
+
+ if File.dir? dest then
+ @fileops.chmod entry.header.mode, dest, :verbose=>false
+ else
+ @fileops.mkdir_p dest, :mode => entry.header.mode, :verbose => false
+ end
+
+ fsync_dir dest
+ fsync_dir File.join(dest, "..")
+
+ return
+ end
+
+ # it's a file
+ md5 = Digest::MD5.new if expected_md5sum
+ destdir = File.join destdir, File.dirname(entry.full_name)
+ @fileops.mkdir_p destdir, :mode => 0755, :verbose => false
+ destfile = File.join destdir, File.basename(entry.full_name)
+ @fileops.chmod 0600, destfile, :verbose => false rescue nil # Errno::ENOENT
+
+ open destfile, "wb", entry.header.mode do |os|
+ loop do
+ data = entry.read 4096
+ break unless data
+ # HACK shouldn't we check the MD5 before writing to disk?
+ md5 << data if expected_md5sum
+ os.write(data)
+ end
+
+ os.fsync
+ end
+
+ @fileops.chmod entry.header.mode, destfile, :verbose => false
+ fsync_dir File.dirname(destfile)
+ fsync_dir File.join(File.dirname(destfile), "..")
+
+ if expected_md5sum && expected_md5sum != md5.hexdigest then
+ raise Gem::Package::BadCheckSum
+ end
+ end
+
+ # Attempt to YAML-load a gemspec from the given _io_ parameter. Return
+ # nil if it fails.
+ def load_gemspec(io)
+ Gem::Specification.from_yaml io
+ rescue Gem::Exception
+ nil
+ end
+
+ ##
+ # Return an IO stream for the zipped entry.
+ #
+ # NOTE: Originally this method used two approaches, Return a GZipReader
+ # directly, or read the GZipReader into a string and return a StringIO on
+ # the string. The string IO approach was used for versions of ZLib before
+ # 1.2.1 to avoid buffer errors on windows machines. Then we found that
+ # errors happened with 1.2.1 as well, so we changed the condition. Then
+ # we discovered errors occurred with versions as late as 1.2.3. At this
+ # point (after some benchmarking to show we weren't seriously crippling
+ # the unpacking speed) we threw our hands in the air and declared that
+ # this method would use the String IO approach on all platforms at all
+ # times. And that's the way it is.
+
+ def zipped_stream(entry)
+ if defined? Rubinius then
+ zis = Zlib::GzipReader.new entry
+ dis = zis.read
+ is = StringIO.new(dis)
+ else
+ # This is Jamis Buck's Zlib workaround for some unknown issue
+ entry.read(10) # skip the gzip header
+ zis = Zlib::Inflate.new(-Zlib::MAX_WBITS)
+ is = StringIO.new(zis.inflate(entry.read))
+ end
+ ensure
+ zis.finish if zis
+ end
+
+end
+
diff --git a/trunk/lib/rubygems/package/tar_output.rb b/trunk/lib/rubygems/package/tar_output.rb
new file mode 100644
index 0000000000..b22f7dd86b
--- /dev/null
+++ b/trunk/lib/rubygems/package/tar_output.rb
@@ -0,0 +1,143 @@
+#++
+# Copyright (C) 2004 Mauricio Julio Fernández Pradier
+# See LICENSE.txt for additional licensing information.
+#--
+
+require 'rubygems/package'
+
+##
+# TarOutput is a wrapper to TarWriter that builds gem-format tar file.
+#
+# Gem-format tar files contain the following files:
+# [data.tar.gz] A gzipped tar file containing the files that compose the gem
+# which will be extracted into the gem/ dir on installation.
+# [metadata.gz] A YAML format Gem::Specification.
+# [data.tar.gz.sig] A signature for the gem's data.tar.gz.
+# [metadata.gz.sig] A signature for the gem's metadata.gz.
+#
+# See TarOutput::open for usage details.
+
+class Gem::Package::TarOutput
+
+ ##
+ # Creates a new TarOutput which will yield a TarWriter object for the
+ # data.tar.gz portion of a gem-format tar file.
+ #
+ # See #initialize for details on +io+ and +signer+.
+ #
+ # See #add_gem_contents for details on adding metadata to the tar file.
+
+ def self.open(io, signer = nil, &block) # :yield: data_tar_writer
+ tar_outputter = new io, signer
+ tar_outputter.add_gem_contents(&block)
+ tar_outputter.add_metadata
+ tar_outputter.add_signatures
+
+ ensure
+ tar_outputter.close
+ end
+
+ ##
+ # Creates a new TarOutput that will write a gem-format tar file to +io+. If
+ # +signer+ is given, the data.tar.gz and metadata.gz will be signed and
+ # the signatures will be added to the tar file.
+
+ def initialize(io, signer)
+ @io = io
+ @signer = signer
+
+ @tar_writer = Gem::Package::TarWriter.new @io
+
+ @metadata = nil
+
+ @data_signature = nil
+ @meta_signature = nil
+ end
+
+ ##
+ # Yields a TarWriter for the data.tar.gz inside a gem-format tar file.
+ # The yielded TarWriter has been extended with a #metadata= method for
+ # attaching a YAML format Gem::Specification which will be written by
+ # add_metadata.
+
+ def add_gem_contents
+ @tar_writer.add_file "data.tar.gz", 0644 do |inner|
+ sio = @signer ? StringIO.new : nil
+ Zlib::GzipWriter.wrap(sio || inner) do |os|
+
+ Gem::Package::TarWriter.new os do |data_tar_writer|
+ def data_tar_writer.metadata() @metadata end
+ def data_tar_writer.metadata=(metadata) @metadata = metadata end
+
+ yield data_tar_writer
+
+ @metadata = data_tar_writer.metadata
+ end
+ end
+
+ # if we have a signing key, then sign the data
+ # digest and return the signature
+ if @signer then
+ digest = Gem::Security::OPT[:dgst_algo].digest sio.string
+ @data_signature = @signer.sign digest
+ inner.write sio.string
+ end
+ end
+
+ self
+ end
+
+ ##
+ # Adds metadata.gz to the gem-format tar file which was saved from a
+ # previous #add_gem_contents call.
+
+ def add_metadata
+ return if @metadata.nil?
+
+ @tar_writer.add_file "metadata.gz", 0644 do |io|
+ begin
+ sio = @signer ? StringIO.new : nil
+ gzos = Zlib::GzipWriter.new(sio || io)
+ gzos.write @metadata
+ ensure
+ gzos.flush
+ gzos.finish
+
+ # if we have a signing key, then sign the metadata digest and return
+ # the signature
+ if @signer then
+ digest = Gem::Security::OPT[:dgst_algo].digest sio.string
+ @meta_signature = @signer.sign digest
+ io.write sio.string
+ end
+ end
+ end
+ end
+
+ ##
+ # Adds data.tar.gz.sig and metadata.gz.sig to the gem-format tar files if
+ # a Gem::Security::Signer was sent to initialize.
+
+ def add_signatures
+ if @data_signature then
+ @tar_writer.add_file 'data.tar.gz.sig', 0644 do |io|
+ io.write @data_signature
+ end
+ end
+
+ if @meta_signature then
+ @tar_writer.add_file 'metadata.gz.sig', 0644 do |io|
+ io.write @meta_signature
+ end
+ end
+ end
+
+ ##
+ # Closes the TarOutput.
+
+ def close
+ @tar_writer.close
+ end
+
+end
+
diff --git a/trunk/lib/rubygems/package/tar_reader.rb b/trunk/lib/rubygems/package/tar_reader.rb
new file mode 100644
index 0000000000..8359399207
--- /dev/null
+++ b/trunk/lib/rubygems/package/tar_reader.rb
@@ -0,0 +1,86 @@
+#++
+# Copyright (C) 2004 Mauricio Julio Fernández Pradier
+# See LICENSE.txt for additional licensing information.
+#--
+
+require 'rubygems/package'
+
+class Gem::Package::TarReader
+
+ include Gem::Package
+
+ class UnexpectedEOF < StandardError; end
+
+ def self.new(io)
+ reader = super
+
+ return reader unless block_given?
+
+ begin
+ yield reader
+ ensure
+ reader.close
+ end
+
+ nil
+ end
+
+ def initialize(io)
+ @io = io
+ @init_pos = io.pos
+ end
+
+ def close
+ end
+
+ def each
+ loop do
+ return if @io.eof?
+
+ header = Gem::Package::TarHeader.from @io
+ return if header.empty?
+
+ entry = Gem::Package::TarReader::Entry.new header, @io
+ size = entry.header.size
+
+ yield entry
+
+ skip = (512 - (size % 512)) % 512
+
+ if @io.respond_to? :seek then
+ # avoid reading...
+ @io.seek(size - entry.bytes_read, IO::SEEK_CUR)
+ else
+ pending = size - entry.bytes_read
+
+ while pending > 0 do
+ bread = @io.read([pending, 4096].min).size
+ raise UnexpectedEOF if @io.eof?
+ pending -= bread
+ end
+ end
+
+ @io.read skip # discard trailing zeros
+
+ # make sure nobody can use #read, #getc or #rewind anymore
+ entry.close
+ end
+ end
+
+ alias each_entry each
+
+ ##
+ # NOTE: Do not call #rewind during #each
+
+ def rewind
+ if @init_pos == 0 then
+ raise Gem::Package::NonSeekableIO unless @io.respond_to? :rewind
+ @io.rewind
+ else
+ raise Gem::Package::NonSeekableIO unless @io.respond_to? :pos=
+ @io.pos = @init_pos
+ end
+ end
+
+end
+
diff --git a/trunk/lib/rubygems/package/tar_reader/entry.rb b/trunk/lib/rubygems/package/tar_reader/entry.rb
new file mode 100644
index 0000000000..dcc66153d8
--- /dev/null
+++ b/trunk/lib/rubygems/package/tar_reader/entry.rb
@@ -0,0 +1,99 @@
+#++
+# Copyright (C) 2004 Mauricio Julio Fernández Pradier
+# See LICENSE.txt for additional licensing information.
+#--
+
+require 'rubygems/package'
+
+class Gem::Package::TarReader::Entry
+
+ attr_reader :header
+
+ def initialize(header, io)
+ @closed = false
+ @header = header
+ @io = io
+ @orig_pos = @io.pos
+ @read = 0
+ end
+
+ def check_closed # :nodoc:
+ raise IOError, "closed #{self.class}" if closed?
+ end
+
+ def bytes_read
+ @read
+ end
+
+ def close
+ @closed = true
+ end
+
+ def closed?
+ @closed
+ end
+
+ def eof?
+ check_closed
+
+ @read >= @header.size
+ end
+
+ def full_name
+ if @header.prefix != "" then
+ File.join @header.prefix, @header.name
+ else
+ @header.name
+ end
+ end
+
+ def getc
+ check_closed
+
+ return nil if @read >= @header.size
+
+ ret = @io.getc
+ @read += 1 if ret
+
+ ret
+ end
+
+ def directory?
+ @header.typeflag == "5"
+ end
+
+ def file?
+ @header.typeflag == "0"
+ end
+
+ def pos
+ check_closed
+
+ bytes_read
+ end
+
+ def read(len = nil)
+ check_closed
+
+ return nil if @read >= @header.size
+
+ len ||= @header.size - @read
+ max_read = [len, @header.size - @read].min
+
+ ret = @io.read max_read
+ @read += ret.size
+
+ ret
+ end
+
+ def rewind
+ check_closed
+
+ raise Gem::Package::NonSeekableIO unless @io.respond_to? :pos=
+
+ @io.pos = @orig_pos
+ @read = 0
+ end
+
+end
+
diff --git a/trunk/lib/rubygems/package/tar_writer.rb b/trunk/lib/rubygems/package/tar_writer.rb
new file mode 100644
index 0000000000..6e11440e22
--- /dev/null
+++ b/trunk/lib/rubygems/package/tar_writer.rb
@@ -0,0 +1,180 @@
+#++
+# Copyright (C) 2004 Mauricio Julio Fernández Pradier
+# See LICENSE.txt for additional licensing information.
+#--
+
+require 'rubygems/package'
+
+class Gem::Package::TarWriter
+
+ class FileOverflow < StandardError; end
+
+ class BoundedStream
+
+ attr_reader :limit, :written
+
+ def initialize(io, limit)
+ @io = io
+ @limit = limit
+ @written = 0
+ end
+
+ def write(data)
+ if data.size + @written > @limit
+ raise FileOverflow, "You tried to feed more data than fits in the file."
+ end
+ @io.write data
+ @written += data.size
+ data.size
+ end
+
+ end
+
+ class RestrictedStream
+
+ def initialize(io)
+ @io = io
+ end
+
+ def write(data)
+ @io.write data
+ end
+
+ end
+
+ def self.new(io)
+ writer = super
+
+ return writer unless block_given?
+
+ begin
+ yield writer
+ ensure
+ writer.close
+ end
+
+ nil
+ end
+
+ def initialize(io)
+ @io = io
+ @closed = false
+ end
+
+ def add_file(name, mode)
+ check_closed
+
+ raise Gem::Package::NonSeekableIO unless @io.respond_to? :pos=
+
+ name, prefix = split_name name
+
+ init_pos = @io.pos
+ @io.write "\0" * 512 # placeholder for the header
+
+ yield RestrictedStream.new(@io) if block_given?
+
+ size = @io.pos - init_pos - 512
+
+ remainder = (512 - (size % 512)) % 512
+ @io.write "\0" * remainder
+
+ final_pos = @io.pos
+ @io.pos = init_pos
+
+ header = Gem::Package::TarHeader.new :name => name, :mode => mode,
+ :size => size, :prefix => prefix
+
+ @io.write header
+ @io.pos = final_pos
+
+ self
+ end
+
+ def add_file_simple(name, mode, size)
+ check_closed
+
+ name, prefix = split_name name
+
+ header = Gem::Package::TarHeader.new(:name => name, :mode => mode,
+ :size => size, :prefix => prefix).to_s
+
+ @io.write header
+ os = BoundedStream.new @io, size
+
+ yield os if block_given?
+
+ min_padding = size - os.written
+ @io.write("\0" * min_padding)
+
+ remainder = (512 - (size % 512)) % 512
+ @io.write("\0" * remainder)
+
+ self
+ end
+
+ def check_closed
+ raise IOError, "closed #{self.class}" if closed?
+ end
+
+ def close
+ check_closed
+
+ @io.write "\0" * 1024
+ flush
+
+ @closed = true
+ end
+
+ def closed?
+ @closed
+ end
+
+ def flush
+ check_closed
+
+ @io.flush if @io.respond_to? :flush
+ end
+
+ def mkdir(name, mode)
+ check_closed
+
+ name, prefix = split_name(name)
+
+ header = Gem::Package::TarHeader.new :name => name, :mode => mode,
+ :typeflag => "5", :size => 0,
+ :prefix => prefix
+
+ @io.write header
+
+ self
+ end
+
+ def split_name(name) # :nodoc:
+ raise Gem::Package::TooLongFileName if name.size > 256
+
+ if name.size <= 100 then
+ prefix = ""
+ else
+ parts = name.split(/\//)
+ newname = parts.pop
+ nxt = ""
+
+ loop do
+ nxt = parts.pop
+ break if newname.size + 1 + nxt.size > 100
+ newname = nxt + "/" + newname
+ end
+
+ prefix = (parts + [nxt]).join "/"
+ name = newname
+
+ if name.size > 100 or prefix.size > 155 then
+ raise Gem::Package::TooLongFileName
+ end
+ end
+
+ return name, prefix
+ end
+
+end
+