get rid of old SVN structure

encode/y_enc.rb

@@ -0,0 +1,151 @@
+require 'zlib'
+
+# yEnc
+#
+# This gem allows you to decode and encode files using the yenc standard.
+
+class YEnc
+
+  attr_reader :filepath, :outputpath, :filename, :filesize, :line
+
+  def initialize filepath, outputpath
+    @filepath = filepath
+    @outputpath = outputpath
+  end
+
+  def crc32
+    @crc32.upcase.strip
+  end
+
+  # Encode file into a yenc text file
+  def encode_to_file outputfilename
+    outputfile = File.new(@outputpath + outputfilename, "w")
+    outputfile.puts "=ybegin size=#{File.size?(@filepath)} line=128 name=#{File.basename @filepath}\n"
+    special = { 0 => nil, 10 => nil, 13 => nil, 61 => nil }
+    File.open(@filepath,'rb') do |f|
+      until f.eof?
+        #Read in 128 bytes at a time
+        buffer = f.read(128)
+        buffer.each_byte do |byte|
+          char_to_write = (byte + 42) % 256
+          if special.has_key?(char_to_write)
+            outputfile.putc '='
+            char_to_write = (char_to_write + 64) % 256
+          end
+          outputfile.putc char_to_write
+        end
+        outputfile.puts "\n"
+      end
+    end
+    outputfile.puts "=yend size=312860 crc32=#{file_crc32(@filepath).upcase}\n"
+    outputfile.close
+  end
+
+  # method only encodes given file and returns yenc encoded string; nothing more, nothing less
+  # Author: Tadeus Dobrovolskij
+  def encode
+    sio = StringIO.new("","w:ASCII-8BIT")
+    special = { 0 => nil, 10 => nil, 13 => nil, 61 => nil }
+    File.open(@filepath,'rb') do |b|
+      until b.eof?
+        buffer = b.read(128)
+        buffer.each_byte do |byte|
+          char_to_write = (byte + 42) % 256
+          if special.has_key?(char_to_write)
+            sio.putc '='
+            char_to_write = (char_to_write + 64) % 256
+          end
+          sio.putc char_to_write
+        end
+        sio.puts "\n"
+      end
+    end
+    result = sio.string
+    sio.close
+    return result
+  end
+
+  def decode
+    if is_yenc?
+            #Continue decoding
+      begin_read = false
+
+      File.open(@filepath, 'r').each_line do |line|
+
+        if begin_read
+          if line.start_with?("=yend")
+            breakdown_endline line
+            begin_read=false
+            break #stop looking through the file we are done
+          end
+          #end of reading lines
+
+          #puts "LINE COUNT: #{line.length}"
+          #Decode and write to binary file
+          esc = false
+          line.each_byte do |c|
+            next if c == 13 or c == 10
+
+            if c == 61 and not esc #escape character hit goto the next one
+              esc = true
+              next
+            else
+              if esc
+                esc = false
+                c = c - 64
+              end
+
+              if c.between?(0,41)
+                decoded = c + 214
+              else
+                decoded = c - 42
+              end
+            end
+            @new_file.putc decoded
+          end
+
+        else
+          if line.start_with?("=ybegin") #This is the begin size
+            breakdown_header line
+            begin_read = true
+            next
+          end
+        end
+      end
+    else
+      false
+    end
+    @new_file.close
+  end
+
+  #Does this pass the crc32 check
+  def pass_crc32?
+    crc32 = file_crc32 @outputpath + @filename
+    crc32.eql?(@crc32.downcase.strip)
+  end
+
+  # Get the CRC32 for a file
+  def file_crc32 filepath
+    f = nil
+    File.open( filepath, "rb") { |h| f = h.read }
+    Zlib.crc32(f,0).to_s(16)
+  end
+
+  private
+
+  def is_yenc?
+    File.read(@filepath).include?("=ybegin")
+  end
+
+  def breakdown_endline line
+    @crc32 = line[/crc32=(.*)/,1] if @crc32.nil?
+  end
+
+  def breakdown_header line
+    @filename=line[/name=(.*)/,1] if @filename.nil?
+    @filesize =line[/size=([^\s]+)/,1] if @filesize.nil?
+    @line=line[/line=([^\s]+)/,1] if @line.nil?
+    @new_file = File.new(@outputpath + @filename, "wb")
+  end
+
+end