vbatts/path-packer-c
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

POC

Browse source
This commit is contained in:
James Bowes 2012-07-27 16:41:44 -03:00
parent abfdbebe28
commit 7742eeb024
1 changed files with 27 additions and 23 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

48
thing.rb
View file

@ -18,13 +18,13 @@ class BitWriter
def initialize(stream) def initialize(stream)
@stream = stream @stream = stream
@byte = '\0' @byte = 0x00
@count = 8 @count = 8
end end
def write(char) def write(char)
if char == '1' if char == '1'
@byte[0] | 1 << @count @byte |= 1 << @count
end end
@count -= 1 @count -= 1
if @count == -1 if @count == -1
@ -32,10 +32,16 @@ class BitWriter
end end
end end
def write_bits(string)
string.each_char do |c|
self.write(c)
end
end
def pad() def pad()
@count = 8 @count = 8
@stream.write(@byte) @stream.write(Array(@byte).pack('C'))
@byte = '\0' @byte = 0x00
end end
end end
@ -209,7 +215,7 @@ def ran_char(val)
return val return val
end end
def binary_write(file, parent, strings) def binary_write(file, parent, string_huff, node_huff)
# file.write(parent.path) # file.write(parent.path)
# file.write("\0") # file.write("\0")
#offset to child node indicies #offset to child node indicies
@ -230,15 +236,16 @@ def binary_write(file, parent, strings)
# file.write(child.path) # file.write(child.path)
# file.write("\0") # file.write("\0")
# index of path string # index of path string
file.write(strings[child.path][1]) file.write_bits(string_huff.encode(child.path))
# offset to node # offset to node
# index of node, that is. # index of node, that is.
file.write(child.offset) file.write_bits(node_huff.encode(child))
end end
# reserve null byte for end of node info # reserve null byte for end of node info
file.write("\0") # 3 0s are reserved in our name huffman table to denote end of node
file.write_bits("000")
parent.children.each do |child| parent.children.each do |child|
binary_write(file, child, strings) binary_write(file, child, string_huff, node_huff)
child.children.written = true child.children.written = true
end end
end end
@ -246,11 +253,12 @@ end
def write_strings(file, strings) def write_strings(file, strings)
string_io = StringIO.new() string_io = StringIO.new()
strings.each_key do |string| strings.each_key do |string|
puts "STRING: " + string
string_io.write(string) string_io.write(string)
string_io.write("\0") string_io.write("\0")
end end
zlib = Zlib::Deflate.new(Zlib::BEST_COMPRESSION, 15, Zlib::MAX_MEM_LEVEL) zlib = Zlib::Deflate.new(Zlib::BEST_COMPRESSION, 15, Zlib::MAX_MEM_LEVEL)
file.write zlib.deflate(string_io.to_s, Zlib::FINISH) file.write zlib.deflate(string_io.string, Zlib::FINISH)
end end
def collect_strings(parent) def collect_strings(parent)
@ -262,22 +270,15 @@ def collect_strings(parent)
strings strings
end end
def build_huffman_for_strings(parent, strings) def build_huffman_for_strings(parent)
nodes = parent.flatten.uniq nodes = parent.flatten.uniq
paths = nodes.collect {|node| node.path} paths = nodes.collect {|node| node.path}
table = HuffmanEncoding.new paths table = HuffmanEncoding.new paths
paths.uniq.each do |string|
puts table.encode(string).to_s + " " + string
end end
def build_huffman_for_nodes(parent)
nodes = parent.flatten nodes = parent.flatten
table = HuffmanEncoding.new nodes table = HuffmanEncoding.new nodes
parent.flatten.uniq do |node|
puts table.encode(node).to_s
end
end end
if $0 == __FILE__ if $0 == __FILE__
@ -323,11 +324,14 @@ if $0 == __FILE__
de_dupe_driver(parent) de_dupe_driver(parent)
parent = compress_prefix(parent) parent = compress_prefix(parent)
strings = collect_strings(parent) string_huff = build_huffman_for_strings(parent)
build_huffman(parent, strings) node_huff = build_huffman_for_nodes(parent)
strings = collect_strings(parent)
write_strings(binary, strings) write_strings(binary, strings)
binary_write(binary, parent, strings) bit_file = BitWriter.new binary
binary_write(bit_file, parent, string_huff, node_huff)
bit_file.pad
file.write(parent.to_json) file.write(parent.to_json)
end end