Nucleide

A crate to manipulate custom sections of a WebAssembly module to view/edit application metadata.

Specification

Nucleide specifies WASM metadata that is read by the Nucleic Desktop Environment. It includes the WebAssembly 2.0 and the Daku 1.0.0-beta.0 specifications.

Daku programs are a WebAssembly module that must have the daku custom section, are compressed with ZStd, and should use the .daku file extension; thus the Nucleide specification, as an extension of Daku, shall follow.

App data that can be displayed by a software manager, and where it comes from:

• Non-Localized App Name: name section => Module Name Subsection
• Programming Language: producers section => Language Field
• Processed With: producers section => Processed-By Field
• Generated With: producers section => SDK Field
• Required Permissions: daku section => Portals Header
• Localized App Names: daku section => Translations Subsection
• App Description: daku section => Description Translations Subsection
• App Icon Themes: daku section => App Icon Themes Subsection
• App Screenshots: daku section => Description Assets Subsection
• Searchable Tags: daku section => Tags Subsection
• Categories: daku section => Categories Subsection
• Organization: daku section => Organization Name Subsection

Types

Nucleide custom sections reuse WebAssembly types:

Byte

Simply an 8-bit integer.

Integer

A Unsigned LEB128 variable-length encoded litte-endian integer, with a maximum value of 2³²-1 (can be anywhere from 1-5 bytes).

Vector[T]

A sequence of the following:

• size: Integer
• data: [T; size]

Name

Containing valid UTF-8 (no null termination); wrapper around:

• Vector[Byte]

NameMap

A Vector, with each element containing a sequence of the following:

• index: Integer - Must be sorted in sequence
• name: Name

IndirectNameMap

A Vector, with each element containing a sequence of the following:

• index: Integer - Must be sorted in sequence
• name_map: NameMap

Custom Sections

Name (name)

From the wasm spec, debug info. It is expected that apps are built with this module generated for easier debugging, but stripped away and put into a separate .name file for distribution.

• subsection: u8: Each subsection is optional, and must be placed in this order:
  • 0 => Module Name
  • 1 => Function Names
  • 2 => Local Names
  • 3 => Ext: Label Names
  • 4 => Ext: Type Names
  • 5 => Ext: Table Names
  • 6 => Ext: Memory Names
  • 7 => Ext: Global Names
  • 8 => Ext: Element Names
  • 9 => Ext: Data Names
• size: u32: Number of bytes

0 => Module Name

• name: Name: Name of the app

1 => Function Names

• name_map: NameMap: Names of each function

2 => Local Names

• indirect_name_map: IndirectNameMap: Names of each variable in each function

3 => Ext: Label Names

• indirect_name_map: IndirectNameMap: Names of each label in each function

4 => Ext: Type Names

• name_map: NameMap: Names of each type

5 => Ext: Table Names

• name_map: NameMap: Names of each table

6 => Ext: Memory Names

• name_map: NameMap: Names of each memory

7 => Ext: Global Names

• name_map: NameMap: Names of each global

8 => Ext: Element Names

• name_map: NameMap: Names of each element

9 => Ext: Data Names

• name_map: NameMap: Names of each data

Producers (producers)

From WebAssembly's tool conventions, information on how the .daku WebAssembly file was generated.

A Vector, with each element containing a sequence of the following:

• name: Name - One of:
  • "language"
  • "processed-by"
  • "sdk"
• tool_version_pairs: Vector<(String, String)>

Daku (daku)

• portals: Vector<Integer>: List of Portal IDs

Following the Daku portals list, is the nucleide extension:

• subsection: u8: Each subsection is optional, and must be placed in this order:
  • 0 => Reserved for potential breaking 2.0 version of Daku
  • 1 => App Name Translations
  • 2 => App Description Translations
  • 3 => App Icon Themes
  • 4 => App Description Assets
  • 5 => Searchable Tags
  • 6 => Searchable Categories
  • 7 => Organization Name
• size: u32: Number of bytes

1 => App Name Translations

• localized_names: NameMap

Integer representation of a 4-letter (2-letter lowercase language, 2-letter uppercase region) locale ASCII description:

• locale: b"enUS"

  locale[0] | locale[1] << 7 | locale[2] << 14 | locale[3] << 21
  

2 => App Description Translations

• localized_mdfiles: NameMap: Markdown file for each description

Integer representation of a 4-letter (2-letter lowercase language, 2-letter uppercase region) locale ASCII description:

• locale: b"enUS"

  locale[0] | locale[1] << 7 | locale[2] << 14 | locale[3] << 21
  

3 => App Icon Themes

A Vector, with each element containing a sequence of the following:

• name: Name: Theme name, "default" or "reduced"; reduced theme should be binary (on/off) RGBA. default is full 0-255 range for each.
• data: Vector<u8>: Concatenated list of QOI (future: or RVG) files. Best resolution out of the files will be chosen. None can have the same resolution.

4 => App Description Assets

A Vector, with each element containing a sequence of the following:

• locale: Integer: Set to 0 for non-localized assets.
• path: Name: Markdown path
• data: Vector<u8>: QOI (future: or RVG) file.

5 => Searchable Tags

A Vector (limit 8), with each element containing:

• tag: Name: Name of the tag (all lowercase ASCII english words separated by spaces; no - or _, other punctuation)

6 => Searchable Categories

A Vector (limit 2), with each element containing:

• tag: Byte: App Category, one of:
  • 0 => Media - Applications for playing / recording / editing audio, video, drawing, photos, fonts, 3D-modeling
  • 1 => Office - Applications for viewing / editing / translating documents and spreadsheets
  • 2 => System - Applications for inspecting the operating system, tweaking, installing, and virtualization
  • 3 => Coding - Applications for software development, math, related tools
  • 4 => Internet - Applications for browsing the web, peer-to-peer file sharing, email, social media, etc.
  • 5 => Gaming - Applications for playing video games
  • 6 => Science - Applications for simulations, electrical/mechanical engineering, A/I for inspecting data, robots
  • 7 => Education - Applications for education, learning
  • 8 => Life - Applications to-do lists, calendar, wellbeing, fitness, directions, mapping, weather, smart home, etc.
  • 9 => Finance - Applications for coupons, buying/selling, trading, currency

7 => Organization Name

• organization: Name: Name of organization that developed the software