#ccc #cc-camp2019 #cc-camp19 #card10 #l0dable

nightly no-std card10-alloc

Dynamic memory allocation for card10 l0dables

2 releases

0.1.1 Sep 8, 2019
0.1.0 Sep 3, 2019

#201 in Memory management

MIT/Apache

9MB
190K SLoC

C 163K SLoC // 0.2% comments SWIG 9K SLoC // 0.2% comments Shell 7.5K SLoC // 0.2% comments Visual Studio Project 5K SLoC GNU Style Assembly 2K SLoC // 0.2% comments Assembly 771 SLoC // 0.1% comments Arduino C++ 765 SLoC // 0.4% comments Automake 761 SLoC // 0.1% comments Python 169 SLoC // 0.4% comments Rust 160 SLoC // 0.0% comments Visual Studio Solution 139 SLoC Perl 96 SLoC // 0.2% comments INI 51 SLoC GDB Script 41 SLoC

Rust support for the card10 CCCamp19 badge

Prepare your card10

Jailbreaking is no longer necessary!

Starting with firmware v1.9, running ELF binaries requires a /card10.cfg with the following content:

execute_elf=true

Prebuilt binaries

By courtesy of this Gitlab's CI system, and NixOS, we build .elf files for you drop into the apps/ directory of your card10 badge.

For each commit in this repository, we also build complete firmware images with the required configuration and our example binaries.

https://git.card10.badge.events.ccc.de/astro/rust-card10/-/jobs

Prerequisites

You need rust nightly and a working setup to compile the card10 firmware including the matching libc.

  1. For instructions how to setup rust please see https://rustup.rs.

    Please ensure that you installed the latest rust nightly toolchain and add the thumbv7em-none-eabi target.

    rustup toolchain install nightly
    rustup update
    rustup target add thumbv7em-none-eabi --toolchain nightly
    
  2. For instructions how to setup the card10 firmware check the dependency chapter in https://firmware.card10.badge.events.ccc.de/how-to-build.html.

  3. Additionally you may need the packages for the llvm and libc i386 dev headers.

  4. Clone this repository with --recursive to get the submodules, otherwise update them afterwards:

    git submodule update --init --recursive
    

Build and run Rust loadables

Setup

If you want to come up with your own rust based loadable crate a few preparations are required:

  • Setup the new crate repository.

  • Add card10-l0dable = "^0.1" as a dependency to your new crate.

  • Change the configuration of the default cargo release profile inside your Cargo.toml file:

    [profile.release]
    opt-level = "s"
    panic = "abort"
    
  • Create (or update) the thumbv7em-none-eabi target configuration at $PROJECT/.cargo/config with the following rustflags:

    [target.thumbv7em-none-eabi]
    rustflags = [
      "-C", "linker=arm-none-eabi-gcc",
      "-C", "link-args=-Tl0dable.ld -n -pie -fPIC",
      "-C", "relocation-model=pic",
    ]
    
    [build]
    target = "thumbv7em-none-eabi"
    
  • Ensure that your crate is marked as a non_std project and make card10-l0dable aware of your custom main function. This should require the following update to your main.rs file.

    #![no_std]
    #![no_main]
    
    use card10_l0dable::main;
    
    main!(main);
    fn main() {}
    

Compilation

To compile the project use the nightly toolchain and define the proper target.

cargo +nightly build --release --target thumbv7em-none-eabi

Transfer to card10

Then copy the resulting executable from the target directory target/thumbv7em-none-eabi/release/example into the apps directory of your badge.

Attention: Its necessary to rename the executable to add the elf extension (e.g example must be renamed as example.elf).

Crates

Crate Documentation Description
card10-sys docs.rs Unsafe C bindings for l0dables
card10-alloc docs.rs alloc::* support for l0dables
card10-l0dable docs.rs High-level crate for building l0dables
example l0dable example
rkanoid Arkanoid clone
draw-image Example of drawing a static image to the display

Misc

How to update the firmware bindings

  1. Update the card10-sys/firmware submodule to the latest firmware state.

  2. Rebuild the firmware as described above.

  3. Run the following script from the project root directory

    python card10-sys/firmware/epicardium/api/genapi.py -H card10-sys/firmware/epicardium/epicardium.h -c card10-sys/vendor/client.c -s card10-sys/vendor/server.c
    
  4. Rebuild your app :)

Dependencies