From fcbf63e62c627deae76c1b8cb8c0876c536ed811 Mon Sep 17 00:00:00 2001 From: Jari Vetoniemi Date: Mon, 16 Mar 2020 18:49:26 +0900 Subject: Fresh start --- jni/ruby/lib/rubygems/package/tar_reader.rb | 123 ++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100644 jni/ruby/lib/rubygems/package/tar_reader.rb (limited to 'jni/ruby/lib/rubygems/package/tar_reader.rb') diff --git a/jni/ruby/lib/rubygems/package/tar_reader.rb b/jni/ruby/lib/rubygems/package/tar_reader.rb new file mode 100644 index 0000000..e257fdd --- /dev/null +++ b/jni/ruby/lib/rubygems/package/tar_reader.rb @@ -0,0 +1,123 @@ +# -*- coding: utf-8 -*- +#-- +# Copyright (C) 2004 Mauricio Julio Fernández Pradier +# See LICENSE.txt for additional licensing information. +#++ + +## +# TarReader reads tar files and allows iteration over their items + +class Gem::Package::TarReader + + include Enumerable + + ## + # Raised if the tar IO is not seekable + + class UnexpectedEOF < StandardError; end + + ## + # Creates a new TarReader on +io+ and yields it to the block, if given. + + def self.new(io) + reader = super + + return reader unless block_given? + + begin + yield reader + ensure + reader.close + end + + nil + end + + ## + # Creates a new tar file reader on +io+ which needs to respond to #pos, + # #eof?, #read, #getc and #pos= + + def initialize(io) + @io = io + @init_pos = io.pos + end + + ## + # Close the tar file + + def close + end + + ## + # Iterates over files in the tarball yielding each entry + + def each + return enum_for __method__ unless block_given? + + until @io.eof? do + 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 + pending = size - entry.bytes_read + + begin + # avoid reading... + @io.seek pending, IO::SEEK_CUR + pending = 0 + rescue Errno::EINVAL, NameError + while pending > 0 do + bytes_read = @io.read([pending, 4096].min).size + raise UnexpectedEOF if @io.eof? + pending -= bytes_read + 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 + + ## + # Seeks through the tar file until it finds the +entry+ with +name+ and + # yields it. Rewinds the tar file to the beginning when the block + # terminates. + + def seek name # :yields: entry + found = find do |entry| + entry.full_name == name + end + + return unless found + + return yield found + ensure + rewind + end + +end + +require 'rubygems/package/tar_reader/entry' + -- cgit v1.2.3