class FastLib
The FastLib
class implements the meat of the FASTLIB archive format
Constants
- FLAG_COMPRESS
- FLAG_ENCRYPT
- VERSION
Public Class Methods
Expose the cache to callers
# File lib/fastlib.rb, line 273 def self.cache @@cache end
This method provides a way to create a FASTLIB archive programatically, the key arguments are the name of the destination archive, the base directory that should be excluded from the archived path, and finally the list of specific files and directories to include in the archive.
# File lib/fastlib.rb, line 182 def self.create(lib, flags, bdir, *dirs) head = "" data = "" hidx = 0 didx = 0 bdir = bdir.gsub(/\/$/, '') brex = /^#{Regexp.escape(bdir)}\// if flags.kind_of?(::String) if flags =~ /^0x/ flags = flags.to_i(16) else flags = flags.to_i end end @@cache[lib] = { :fastlib_flags => flags } dirs.each do |dir| ::Find.find(dir).each do |path| next if not ::File.file?(path) name = fastlib_filter_encode( lib, path.sub( brex, "" ) ) buff = "" ::File.open(path, "rb") do |fd| buff = fastlib_filter_encode(lib, fd.read(fd.stat.size)) end head << [ name.length, didx, buff.length, ::File.stat(path).mtime.utc.to_i ].pack("NNNN") head << name hidx = hidx + 16 + name.length data << buff didx = didx + buff.length end end head << [0,0,0].pack("NNN") ::File.open(lib, "wb") do |fd| fd.write("FAST") fd.write( [ head.length, flags ].pack("NN") ) fd.write( head ) fd.write( data ) end end
# File lib/fastlib.rb, line 266 def self.decrypt_00000000(data) encrypt_00000000(data) end
# File lib/fastlib.rb, line 258 def self.decrypt_12345600(data) encrypt_00000000(data) end
# File lib/fastlib.rb, line 262 def self.encrypt_00000000(data) data.unpack("C*").map{ |c| c ^ 0x90 }.pack("C*") end
This is a stub crypto handler that performs a basic XOR operation against a fixed one byte key. The two usable IDs are 12345600 and 00000000
# File lib/fastlib.rb, line 254 def self.encrypt_12345600(data) encrypt_00000000(data) end
This method provides compression and encryption capabilities for the fastlib archive format.
# File lib/fastlib.rb, line 119 def self.fastlib_filter_decode(lib, buff) if (@@cache[lib][:fastlib_flags] & FLAG_ENCRYPT) != 0 @@cache[lib][:fastlib_decrypt] ||= ::Proc.new do |data| stub = "decrypt_%.8x" % ( @@cache[lib][:fastlib_flags] & 0xfffffff0 ) FastLib.send(stub, data) end buff = @@cache[lib][:fastlib_decrypt].call( buff ) end if (@@cache[lib][:fastlib_flags] & FLAG_COMPRESS) != 0 if not @@has_zlib raise ::RuntimeError, "zlib is required to open this archive" end z = Zlib::Inflate.new buff = z.inflate(buff) buff << z.finish z.close end buff end
This method provides compression and encryption capabilities for the fastlib archive format.
# File lib/fastlib.rb, line 149 def self.fastlib_filter_encode(lib, buff) if (@@cache[lib][:fastlib_flags] & FLAG_COMPRESS) != 0 if not @@has_zlib raise ::RuntimeError, "zlib is required to open this archive" end z = Zlib::Deflate.new buff = z.deflate(buff) buff << z.finish z.close end if (@@cache[lib][:fastlib_flags] & FLAG_ENCRYPT) != 0 @@cache[lib][:fastlib_encrypt] ||= ::Proc.new do |data| stub = "encrypt_%.8x" % ( @@cache[lib][:fastlib_flags] & 0xfffffff0 ) FastLib.send(stub, data) end buff = @@cache[lib][:fastlib_encrypt].call( buff ) end buff end
This method provides a way to list the contents of an archive file, returning the names only in sorted order.
# File lib/fastlib.rb, line 236 def self.list(lib) load_cache(lib) ( @@cache[lib] || {} ).keys.map{|x| x.to_s }.sort.select{ |x| @@cache[lib][x] } end
This method loads content from a specific archive file by name. If the noprocess argument is set to true, the contents will not be expanded to include workarounds for things such as __FILE__. This is useful when loading raw binary data where these strings may occur
# File lib/fastlib.rb, line 62 def self.load(lib, name, noprocess=false) data = "" load_cache(lib) return if not ( @@cache[lib] and @@cache[lib][name] ) ::File.open(lib, "rb") do |fd| fd.seek( @@cache[lib][:fastlib_header][0] + @@cache[lib][:fastlib_header][1] + @@cache[lib][name][0] ) data = fastlib_filter_decode( lib, fd.read(@@cache[lib][name][1] )) end # Return the contents in raw or processed form noprocess ? data : post_process(lib, name, data) end
This method caches the file list and offsets within the archive
# File lib/fastlib.rb, line 85 def self.load_cache(lib) return if @@cache[lib] @@cache[lib] = {} return if not ::File.exists?(lib) ::File.open(lib, 'rb') do |fd| dict = {} head = fd.read(4) return if head != "FAST" hlen = fd.read(4).unpack("N")[0] flag = fd.read(4).unpack("N")[0] @@cache[lib][:fastlib_header] = [12, hlen, fd.stat.mtime.utc.to_i ] @@cache[lib][:fastlib_flags] = flag nlen, doff, dlen, tims = fd.read(16).unpack("N*") while nlen > 0 name = fastlib_filter_decode( lib, fd.read(nlen) ) dict[name] = [doff, dlen, tims] nlen, doff, dlen, tims = fd.read(16).unpack("N*") end @@cache[lib].merge!(dict) end end
This method is expands __FILE__ sequences and other inline dynamic constants to map to the correct location.
# File lib/fastlib.rb, line 245 def self.post_process(lib, name, data) data.gsub('__FILE__', "'#{ ::File.expand_path(::File.join(::File.dirname(lib), name)) }'") end
This method returns the version of the fastlib library
# File lib/fastlib.rb, line 52 def self.version VERSION end