first commit

.formatter.exs

@@ -0,0 +1,4 @@
+# Used by "mix format"
+[
+  inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"]
+]

.gitignore

@@ -0,0 +1,27 @@
+# The directory Mix will write compiled artifacts to.
+/_build/
+
+# If you run "mix test --cover", coverage assets end up here.
+/cover/
+
+# The directory Mix downloads your dependencies sources to.
+/deps/
+
+# Where third-party dependencies like ExDoc output generated docs.
+/doc/
+
+# Ignore .fetch files in case you like to edit your project deps locally.
+/.fetch
+
+# If the VM crashes, it generates a dump, let's ignore it too.
+erl_crash.dump
+
+# Also ignore archive artifacts (built via "mix archive.build").
+*.ez
+
+# Ignore package tarball (built via "mix hex.build").
+dotzip-*.tar
+
+
+# Temporary files for e.g. tests
+/tmp

README.md

@@ -0,0 +1,19 @@
+# Dotzip
+
+## Installation
+
+If [available in Hex](https://hex.pm/docs/publish), the package can be installed
+by adding `dotzip` to your list of dependencies in `mix.exs`:
+
+```elixir
+def deps do
+  [
+    {:dotzip, "~> 0.1.0"}
+  ]
+end
+```
+
+Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
+and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
+be found at [https://hexdocs.pm/dotzip](https://hexdocs.pm/dotzip).
+

lib/dotzip.ex

@@ -0,0 +1,227 @@
+defmodule Dotzip do
+  
+  @moduledoc """
+  Elixir Implementation of ZIP File Format. https://pkware.cachefly.net/webdocs/APPNOTE/APPNOTE-6.3.3.TXT
+  """
+
+  def decode(file) do
+    {:ok, local, rest} = Dotzip.LocalFileHeader.decode(file)
+    {:ok, central, r} = Dotzip.CentralDirectoryHeader.decode(rest)
+    {:ok, e, rr} = Dotzip.EndCentralDirectory.decode(r)
+    {local, central, e, rr}
+  end
+  
+end
+
+defmodule Dotzip.LocalFileHeader do
+  
+  defp signature(<< 0x50, 0x4b, 0x03, 0x04, rest::bitstring >>) do
+    {:ok, %{}, rest}
+  end
+
+  defp version({:ok, data, << version::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :version, version), rest}
+  end
+
+  defp purpose_flag({:ok, data, << purpose_flag::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :purpose_flag, purpose_flag), rest}
+  end
+
+  defp compression_method({:ok, data, << compression_method::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :compression_method, compression_method), rest}
+  end
+
+  defp last_modification_time({:ok, data, << last_modification::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :last_modification_time, last_modification), rest}
+  end
+
+  defp last_modification_date({:ok, data, << last_modification_date::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :last_modification_date, last_modification_date), rest}
+  end
+
+  defp crc32({:ok, data, << crc32::binary-size(4), rest::bitstring >>}) do
+   {:ok, Map.put(data, :crc32, crc32), rest} 
+  end
+
+  defp compressed_size({:ok, data, << compressed_size::little-size(32), rest::bitstring >>}) do
+    {:ok, Map.put(data, :compressed_size, compressed_size), rest}
+  end
+
+  defp uncompressed_size({:ok, data, << uncompressed_size::little-size(32), rest::bitstring >>}) do
+    {:ok, Map.put(data, :uncompressed_size, uncompressed_size), rest}
+  end
+
+  defp file_name_length({:ok, data, << file_name_length::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :file_name_length, file_name_length), rest }
+  end
+
+  defp extra_field_length({:ok, data, << extra_field_length::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :extra_field_length, extra_field_length), rest}
+  end
+
+  defp file_name({:ok, data, rest}) do
+    %{ :file_name_length => file_name_length } = data
+    <<file_name::binary-size(file_name_length), r::bitstring>> = rest
+    {:ok, Map.put(data, :file_name, file_name), r}
+  end
+
+  defp extra_field({:ok, data, rest}) do
+    %{ :extra_field_length => extra_field_length } = data
+    <<extra_field::binary-size(extra_field_length), r::bitstring>> = rest
+    {:ok, Map.put(data, :extra_field, extra_field), r}
+  end
+
+  defp content({:ok, data, rest}) do
+    %{ :compressed_size => compressed_size } = data
+    <<content::binary-size(compressed_size), r::bitstring>> = rest
+    {:ok, Map.put(data, :content, content), r}
+  end
+  
+  def decode(file) do
+    {:ok, local_file_header, rest} = signature(file)
+    |> version()
+    |> purpose_flag()
+    |> compression_method()
+    |> last_modification_time()
+    |> last_modification_date()
+    |> crc32()
+    |> compressed_size()
+    |> uncompressed_size()
+    |> file_name_length()
+    |> extra_field_length()
+    |> file_name()
+    |> extra_field()
+    |> content()
+    end
+  
+end
+
+defmodule Dotzip.CentralDirectoryHeader do
+
+  defp signature(<< 0x50, 0x4b, 0x01, 0x02, rest::bitstring >>) do
+    {:ok, %{}, rest}
+  end
+
+  defp version_made({:ok, data, << version::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :version_made, version), rest}
+  end
+
+  defp version_needed({:ok, data, << version::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :version_needed, version), rest}
+  end
+  
+  defp purpose_flag({:ok, data, << purpose_flag::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :purpose_flag, purpose_flag), rest}
+  end
+
+  defp compression_method({:ok, data, << compression_method::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :compression_method, compression_method), rest}
+  end
+
+  defp last_modification_time({:ok, data, << last_modification::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :last_modification_time, last_modification), rest}
+  end
+
+  defp last_modification_date({:ok, data, << last_modification_date::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :last_modification_date, last_modification_date), rest}
+  end
+
+  defp crc32({:ok, data, << crc32::binary-size(4), rest::bitstring >>}) do
+   {:ok, Map.put(data, :crc32, crc32), rest} 
+  end
+
+  defp compressed_size({:ok, data, << compressed_size::little-size(32), rest::bitstring >>}) do
+    {:ok, Map.put(data, :compressed_size, compressed_size), rest}
+  end
+
+  defp uncompressed_size({:ok, data, << uncompressed_size::little-size(32), rest::bitstring >>}) do
+    {:ok, Map.put(data, :uncompressed_size, uncompressed_size), rest}
+  end
+
+  defp file_name_length({:ok, data, << file_name_length::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :file_name_length, file_name_length), rest }
+  end
+
+  defp extra_field_length({:ok, data, << extra_field_length::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :extra_field_length, extra_field_length), rest}
+  end
+
+  defp file_comment_length({:ok, data, << file_comment_length::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :file_comment_length, file_comment_length), rest}
+  end
+
+  defp disk_number_start({:ok, data, << disk_number_start::little-size(16), rest::bitstring >>}) do
+    {:ok, Map.put(data, :disk_number_start, disk_number_start), rest}
+  end
+
+  defp internal_file_attributes({:ok, data, << internal_file_attributes::binary-size(2), rest::bitstring >>}) do
+    {:ok, Map.put(data, :internal_file_attributes, internal_file_attributes), rest}
+  end
+
+  defp external_file_attributes({:ok, data, << external_file_attributes::binary-size(4), rest::bitstring >>}) do
+    {:ok, Map.put(data, :external_file_attributes, external_file_attributes), rest}
+  end
+
+  defp relative_offset({:ok, data, << relative_offset::little-size(32), rest::bitstring >>}) do
+    {:ok, Map.put(data, :relative_offset, relative_offset), rest}
+  end
+
+  defp file_name({:ok, data, rest}) do
+    %{ :file_name_length => file_name_length } = data
+    <<file_name::binary-size(file_name_length), r::bitstring>> = rest
+    {:ok, Map.put(data, :file_name, file_name), r}
+  end
+
+  defp extra_field({:ok, data, rest}) do
+    %{ :extra_field_length => extra_field_length } = data
+    <<extra_field::binary-size(extra_field_length), r::bitstring>> = rest
+    {:ok, Map.put(data, :extra_field, extra_field), r}
+  end
+
+  defp file_comment({:ok, data, rest}) do
+    %{ :file_comment_length => file_comment_length } = data
+    <<file_comment::binary-size(file_comment_length), r::bitstring>> = rest
+    {:ok, Map.put(data, :file_comment, file_comment), r}
+  end
+  
+  def decode(file) do
+    {:ok, central_directory_header, rest} = signature(file)
+    |> version_made()
+    |> version_needed()
+    |> purpose_flag()
+    |> compression_method()
+    |> last_modification_time()
+    |> last_modification_date()
+    |> crc32()
+    |> compressed_size()
+    |> uncompressed_size()
+    |> file_name_length()
+    |> extra_field_length()
+    |> file_comment_length()
+    |> disk_number_start()
+    |> internal_file_attributes()
+    |> external_file_attributes()
+    |> relative_offset()
+    |> file_name()
+    |> extra_field()
+    |> file_comment()
+  end
+  
+end
+
+defmodule Dotzip.EndCentralDirectory do
+  
+  defp signature(<< 0x50, 0x4b, 0x05, 0x06, rest::bitstring >>) do
+    {:ok, %{}, rest}
+  end
+
+  defp number_disk({:ok, data, << number_disk::little-size(32), rest::bitstring >>}) do
+    {:ok, Map.put(data, :number_disk, number_disk), rest}
+  end
+
+  def decode(file) do
+    {:ok, end_central_directory, rest} = signature(file)
+    |> number_disk()
+  end
+  
+end

mix.exs

@@ -0,0 +1,28 @@
+defmodule Dotzip.MixProject do
+  use Mix.Project
+
+  def project do
+    [
+      app: :dotzip,
+      version: "0.1.0",
+      elixir: "~> 1.11",
+      start_permanent: Mix.env() == :prod,
+      deps: deps()
+    ]
+  end
+
+  # Run "mix help compile.app" to learn about applications.
+  def application do
+    [
+      extra_applications: [:logger]
+    ]
+  end
+
+  # Run "mix help deps" to learn about dependencies.
+  defp deps do
+    [
+      # {:dep_from_hexpm, "~> 0.3.0"},
+      # {:dep_from_git, git: "https://github.com/elixir-lang/my_dep.git", tag: "0.1.0"}
+    ]
+  end
+end

test/dotzip_test.exs

@@ -0,0 +1,8 @@
+defmodule DotzipTest do
+  use ExUnit.Case
+  doctest Dotzip
+
+  test "local file header" do
+    assert :world == :world
+  end
+end

test/test_helper.exs

@@ -0,0 +1 @@
+ExUnit.start()