#target #config #platform #path #toml #manifest #cmake #flat-file


Parsing, transformation and validation for feL4 manifests

2 releases

Uses old Rust 2015

0.3.2 Oct 22, 2018
0.3.1 Sep 21, 2018

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Used in 2 crates

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Parsing, transformation and validation for feL4 manifests.

The primary purpose of this library is to parse and validate fel4.toml files, which contain configuration options relevant to building seL4 with the help of the cargo-fel4 tool.

The secondary purpose of this library is to actually assist in applying these configuration values to the CMake based build process of seL4, as encapsulated by the libsel4-sys repository.

Getting Started


fel4-config manages its dependencies through its Cargo.toml file, as usual for Rust projects.


fel4-config should build on the stable or nightly Rust toolchains.

  • Acquire a Rust toolchain

  • Retrieve the repository from git:

    git clone https://github.com/maindotrs/fel4-config.git
    cd fel4-config
  • Build using cargo

    cargo build


fel4-config may be included in your Rust project by adding the following to your Cargo.toml.

  • In your relevant [dependencies] section:

    fel4-config = "0.3"


feL4 manifest files are typically named fel4.toml and live at the root directory of a feL4 project. You typically don't have to manufacture them from scratch, as the cargo-fel4 tool will generate a complete manifest as part of the cargo fel4 new command.

A feL4 manifest consists of a [fel4] header section followed by target-specific tables.

The [fel4] table selects the build-target-and-platform pair that your project will be built for, along with some book-keeping

# The Rust build target triple that your feL4 project has selected
# Currently "x86_64-sel4-fel4", "armv7-sel4-fel4", and "aarch64-sel4-fel4" are the available options
target = "x86_64-sel4-fel4"

# The associated platform for your build target.
# "pc99" is available in combination with the "x86_64-sel4-fel4" target
# "sabre" is available in combination with the "armv7-sel4-fel4" target
# "tx1" is available in combination with the "aarch64-sel4-fel4" target
platform = "pc99"

# The path relative to your project root dir where feL4 output build artifacts will be stored
artifact-path = "artifacts"

# The path relative to your project root where the Rust target JSON specifications are stored
# `cargo fel4 new` will generate these specifications for you by default
target-specs-path = "target_specs"

# For the target triple you have selected, there ought to be a toml table
# and a few nested subtables.

# The top-level target table,
BuildWithCommonSimulationSettings = true
KernelOptimisation = "-O2"
# ... Snip ... many more configuration options are possible

# A subtable with configuration options specific to the selected plaform, [$TARGET.$PLATFORM]
# Even if multiple platforms are defined in the toml for a target, only the options
# from the subtable matching the platform selected in the [fel4] header table's
# "platform" field will be applied to the final configuration.
KernelX86MicroArch = "nehalem"
LibPlatSupportX86ConsoleDevice = "com1"

# [$TARGET.debug], a subtable with options only applied for debug builds
KernelDebugBuild = true
KernelPrinting = true

# [$TARGET.debug], a subtable with options only applied for release builds
KernelDebugBuild = false
KernelPrinting = false

  • There are two key types provided by fel4-config, FullFel4Manifest and Fel4Config. FullFel4Manifest represents the entire contents of a fel4.toml, and can be produced by means of get_full_manifest(::std::path::Path::new("./fel4.toml"))? or parse_full_manifest. These methods conduct parsing and basic validation of the manifest contents.

    Fel4Config represents a coalesced subset of the contents of a manifest, applied for a particular target, platform, and build profile. You can create a Fel4Config from a FullFel4Manifest using resolve_fel4_config.

    let full:FullFel4Manifest = get_full_manifest(manifest_file.path())
        .expect("Should be able to read the fel4.toml file");
    let config:Fel4Config = resolve_fel4_config(full, &BuildProfile::Debug)
        .expect("Should have been able to resolve a config");

    Fel4Config contains a resolved, deduplicated set of configuration properties.

    Current applications include use in libsel4-sys CMake configuration, cargo-fel4 code generation, and so forth.

    See the generated Rust documents for details on individual types and functions.

    cargo doc --open



fel4-config makes use of the integrated test framework in Rust. Test dependencies are managed through Cargo.toml [dev-dependencies]


To confirm that the tests build correctly:

cargo build --tests


Tests are executable in the usual way for Rust projects:

cargo test


Please see the LICENSE file for more details


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