swfasm

A textual representation of SWF files, with a compiler that turns it into SWF files.

swfasm test.swfasm         # writes test.swf
swfasm test.swfasm -o out.swf

The command line tool is in the swfasm-cli crate (in cli/), and the compiler is in the swfasm library crate.

cargo install swfasm-cli

Format

Sources use the .swfasm extension and are written in RON, with the implicit_some extension enabled (optional values don't need Some(...)). See examples/ and src/source.rs for everything that is supported.

Tags

Tags are named after SWF tags, see Tag in src/source.rs for the ones that are supported. In addition, there are special tags that give control over the raw encoding:

• Raw(code: 26, data: InlineBytes("01 02 ff")) emits a tag with an arbitrary code and a body given as data. Set force_long: true to use the long (6 byte) header form even for a short body.

AVM1 actions

DoAction(InlineBytes("96 02 00 05 01 26")) takes AVM1 bytecode as data.

Data

Tags that hold data, like Raw, DoAction and DefineBinaryData, take it either inline or from a file:

DefineBinaryData(id: 1, data: InlineBytes("de ad be ef")),
DefineBinaryData(id: 2, data: File("data.bin")),

Inline bytes are written as a hex string with optional whitespace ("01 02 ff"), or a list of hex strings, which are concatenated. The list form allows commenting individual parts:

Raw(code: 1, data: InlineBytes([
    "0a 00", // frame count
    "ff ff", // flags
])),

Paths of files are relative to the directory of the .swfasm file.

Data can also be compiled from ActionScript:

// AVM1 bytecode, compiled by Rascal from ActionScript 2.
DoAction(Rascal(r#"trace("hello");"#)),
// An ABC file, compiled by asc from ActionScript 3. It runs Java, which has to
// be installed.
DoAbc(Asc(file: "Main.as", scripts: ["pkg/Other.as"])),

See examples/rascal.swfasm and examples/asc.swfasm for their options. They are behind the rascal and asc features of the library, enabled by default. asc and the playerglobal that scripts are compiled against are given to the compiler, the asc-vendored feature includes copies of them (see vendor/asc), which the command line tool uses unless --asc-jar or --playerglobal is given.

TODO

• Symbolic character IDs (e.g. @name) instead of numbers.
• Remaining tags (a lot of them).
• Loading other data from files (e.g. images and sounds).
• Better error messages.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.